Adding upstream version 6.1.0.upstream/6.1.0upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

31 files changed, 11765 insertions, 0 deletions

diff --git a/lib/Makefile b/lib/Makefile
new file mode 100644
index 0000000..ddedd37
--- /dev/null
+++ b/lib/Makefile
@@ -0,0 +1,32 @@
+# SPDX-License-Identifier: GPL-2.0
+include ../config.mk
+
+CFLAGS += -fPIC
+
+UTILOBJ = utils.o utils_math.o rt_names.o ll_map.o ll_types.o ll_proto.o ll_addr.o \
+	inet_proto.o namespace.o json_writer.o json_print.o json_print_math.o \
+	names.o color.o bpf_legacy.o bpf_glue.o exec.o fs.o cg_map.o ppp_proto.o
+
+ifeq ($(HAVE_ELF),y)
+ifeq ($(HAVE_LIBBPF),y)
+UTILOBJ += bpf_libbpf.o
+endif
+endif
+
+NLOBJ=libgenl.o libnetlink.o
+ifeq ($(HAVE_MNL),y)
+NLOBJ += mnl_utils.o
+endif
+
+all: libnetlink.a libutil.a
+
+libnetlink.a: $(NLOBJ)
+	$(QUIET_AR)$(AR) rcs $@ $^
+
+libutil.a: $(UTILOBJ) $(ADDLIB)
+	$(QUIET_AR)$(AR) rcs $@ $^
+
+install:
+
+clean:
+	rm -f $(NLOBJ) $(UTILOBJ) $(ADDLIB) libnetlink.a libutil.a
diff --git a/lib/ax25_ntop.c b/lib/ax25_ntop.c
new file mode 100644
index 0000000..3a72a43
--- /dev/null
+++ b/lib/ax25_ntop.c
@@ -0,0 +1,82 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+
+#include <errno.h>
+#include <sys/socket.h>
+#include <linux/ax25.h>
+
+#include "utils.h"
+
+const char *ax25_ntop1(const ax25_address *src, char *dst, socklen_t size);
+
+/*
+ * AX.25 addresses are based on Amateur radio callsigns followed by an SSID
+ * like XXXXXX-SS where the callsign consists of up to 6 ASCII characters
+ * which are either letters or digits and the SSID is a decimal number in the
+ * range 0..15.
+ * Amateur radio callsigns are assigned by a country's relevant authorities
+ * and are 3..6 characters though a few countries have assigned callsigns
+ * longer than that.  AX.25 is not able to handle such longer callsigns.
+ * There are further restrictions on the format of valid callsigns by
+ * applicable national and international law.  Linux doesn't need to care and
+ * will happily accept anything that consists of 6 ASCII characters in the
+ * range of A-Z and 0-9 for a callsign such as the default AX.25 MAC address
+ * LINUX-1 and the default broadcast address QST-0.
+ * The SSID is just a number and not encoded in ASCII digits.
+ *
+ * Being based on HDLC AX.25 encodes addresses by shifting them one bit left
+ * thus zeroing bit 0, the HDLC extension bit for all but the last bit of
+ * a packet's address field but for our purposes here we're not considering
+ * the HDLC extension bit that is it will always be zero.
+ *
+ * Linux' internal representation of AX.25 addresses in Linux is very similar
+ * to this on the on-air or on-the-wire format.  The callsign is padded to
+ * 6 octets by adding spaces, followed by the SSID octet then all 7 octets
+ * are left-shifted by one bit.
+ *
+ * For example, for the address "LINUX-1" the callsign is LINUX and SSID is 1
+ * the internal format is 98:92:9c:aa:b0:40:02.
+ */
+
+const char *ax25_ntop1(const ax25_address *src, char *dst, socklen_t size)
+{
+	char c, *s;
+	int n;
+
+	for (n = 0, s = dst; n < 6; n++) {
+		c = (src->ax25_call[n] >> 1) & 0x7f;
+		if (c != ' ')
+			*s++ = c;
+	}
+
+	*s++ = '-';
+
+	n = ((src->ax25_call[6] >> 1) & 0x0f);
+	if (n > 9) {
+		*s++ = '1';
+		n -= 10;
+	}
+
+	*s++ = n + '0';
+	*s++ = '\0';
+
+	if (*dst == '\0' || *dst == '-') {
+		dst[0] = '*';
+		dst[1] = '\0';
+	}
+
+	return dst;
+}
+
+const char *ax25_ntop(int af, const void *addr, char *buf, socklen_t buflen)
+{
+	switch (af) {
+	case AF_AX25:
+		errno = 0;
+		return ax25_ntop1((ax25_address *)addr, buf, buflen);
+
+	default:
+		errno = EAFNOSUPPORT;
+	}
+
+	return NULL;
+}
diff --git a/lib/bpf_glue.c b/lib/bpf_glue.c
new file mode 100644
index 0000000..88a2475
--- /dev/null
+++ b/lib/bpf_glue.c
@@ -0,0 +1,91 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * bpf_glue.c:	BPF code to call both legacy and libbpf code
+ * Authors:	Hangbin Liu <haliu@redhat.com>
+ *
+ */
+#include <sys/syscall.h>
+#include <limits.h>
+#include <unistd.h>
+#include <errno.h>
+
+#include "bpf_util.h"
+#ifdef HAVE_LIBBPF
+#include <bpf/bpf.h>
+#endif
+
+int bpf(int cmd, union bpf_attr *attr, unsigned int size)
+{
+#ifdef __NR_bpf
+	return syscall(__NR_bpf, cmd, attr, size);
+#else
+	fprintf(stderr, "No bpf syscall, kernel headers too old?\n");
+	errno = ENOSYS;
+	return -1;
+#endif
+}
+
+int bpf_program_attach(int prog_fd, int target_fd, enum bpf_attach_type type)
+{
+#ifdef HAVE_LIBBPF
+	return bpf_prog_attach(prog_fd, target_fd, type, 0);
+#else
+	return bpf_prog_attach_fd(prog_fd, target_fd, type);
+#endif
+}
+
+#ifdef HAVE_LIBBPF
+static const char *_libbpf_compile_version = LIBBPF_VERSION;
+static char _libbpf_version[10] = {};
+
+const char *get_libbpf_version(void)
+{
+	/* Start by copying compile-time version into buffer so we have a
+	 * fallback value in case we are dynamically linked, or can't find a
+	 * version in /proc/self/maps below.
+	 */
+	strncpy(_libbpf_version, _libbpf_compile_version,
+		sizeof(_libbpf_version)-1);
+#ifdef LIBBPF_DYNAMIC
+	char buf[PATH_MAX], *s;
+	bool found = false;
+	FILE *fp;
+
+	/* When dynamically linking against libbpf, we can't be sure that the
+	 * version we discovered at compile time is actually the one we are
+	 * using at runtime. This can lead to hard-to-debug errors, so we try to
+	 * discover the correct version at runtime.
+	 *
+	 * The simple solution to this would be if libbpf itself exported a
+	 * version in its API. But since it doesn't, we work around this by
+	 * parsing the mappings of the binary at runtime, looking for the full
+	 * filename of libbpf.so and using that.
+	 */
+	fp = fopen("/proc/self/maps", "r");
+	if (fp == NULL)
+		goto out;
+
+	while (fgets(buf, sizeof(buf), fp) != NULL) {
+		if ((s = strstr(buf, "libbpf.so.")) != NULL) {
+			strncpy(_libbpf_version, s+10, sizeof(_libbpf_version)-1);
+			strtok(_libbpf_version, "\n");
+			found = true;
+			break;
+		}
+	}
+
+	fclose(fp);
+out:
+	if (!found)
+		fprintf(stderr, "Couldn't find runtime libbpf version - falling back to compile-time value!\n");
+#endif /* LIBBPF_DYNAMIC */
+
+	_libbpf_version[sizeof(_libbpf_version)-1] = '\0';
+	return _libbpf_version;
+}
+#else
+const char *get_libbpf_version(void)
+{
+	return NULL;
+}
+#endif /* HAVE_LIBBPF */
diff --git a/lib/bpf_legacy.c b/lib/bpf_legacy.c
new file mode 100644
index 0000000..4fabdcc
--- /dev/null
+++ b/lib/bpf_legacy.c
@@ -0,0 +1,3360 @@
+/*
+ * bpf.c	BPF common code
+ *
+ *		This program is free software; you can distribute it and/or
+ *		modify it under the terms of the GNU General Public License
+ *		as published by the Free Software Foundation; either version
+ *		2 of the License, or (at your option) any later version.
+ *
+ * Authors:	Daniel Borkmann <daniel@iogearbox.net>
+ *		Jiri Pirko <jiri@resnulli.us>
+ *		Alexei Starovoitov <ast@kernel.org>
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <stdarg.h>
+#include <limits.h>
+#include <assert.h>
+
+#ifdef HAVE_ELF
+#include <libelf.h>
+#include <gelf.h>
+#endif
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/un.h>
+#include <sys/vfs.h>
+#include <sys/mount.h>
+#include <sys/sendfile.h>
+#include <sys/resource.h>
+
+#include <arpa/inet.h>
+
+#include "utils.h"
+#include "json_print.h"
+
+#include "bpf_util.h"
+#include "bpf_elf.h"
+#include "bpf_scm.h"
+
+struct bpf_prog_meta {
+	const char *type;
+	const char *subdir;
+	const char *section;
+	bool may_uds_export;
+};
+
+static const enum bpf_prog_type __bpf_types[] = {
+	BPF_PROG_TYPE_SCHED_CLS,
+	BPF_PROG_TYPE_SCHED_ACT,
+	BPF_PROG_TYPE_XDP,
+	BPF_PROG_TYPE_LWT_IN,
+	BPF_PROG_TYPE_LWT_OUT,
+	BPF_PROG_TYPE_LWT_XMIT,
+};
+
+static const struct bpf_prog_meta __bpf_prog_meta[] = {
+	[BPF_PROG_TYPE_SCHED_CLS] = {
+		.type		= "cls",
+		.subdir		= "tc",
+		.section	= ELF_SECTION_CLASSIFIER,
+		.may_uds_export	= true,
+	},
+	[BPF_PROG_TYPE_SCHED_ACT] = {
+		.type		= "act",
+		.subdir		= "tc",
+		.section	= ELF_SECTION_ACTION,
+		.may_uds_export	= true,
+	},
+	[BPF_PROG_TYPE_XDP] = {
+		.type		= "xdp",
+		.subdir		= "xdp",
+		.section	= ELF_SECTION_PROG,
+	},
+	[BPF_PROG_TYPE_LWT_IN] = {
+		.type		= "lwt_in",
+		.subdir		= "ip",
+		.section	= ELF_SECTION_PROG,
+	},
+	[BPF_PROG_TYPE_LWT_OUT] = {
+		.type		= "lwt_out",
+		.subdir		= "ip",
+		.section	= ELF_SECTION_PROG,
+	},
+	[BPF_PROG_TYPE_LWT_XMIT] = {
+		.type		= "lwt_xmit",
+		.subdir		= "ip",
+		.section	= ELF_SECTION_PROG,
+	},
+	[BPF_PROG_TYPE_LWT_SEG6LOCAL] = {
+		.type		= "lwt_seg6local",
+		.subdir		= "ip",
+		.section	= ELF_SECTION_PROG,
+	},
+};
+
+static const char *bpf_prog_to_subdir(enum bpf_prog_type type)
+{
+	assert(type < ARRAY_SIZE(__bpf_prog_meta) &&
+	       __bpf_prog_meta[type].subdir);
+	return __bpf_prog_meta[type].subdir;
+}
+
+const char *bpf_prog_to_default_section(enum bpf_prog_type type)
+{
+	assert(type < ARRAY_SIZE(__bpf_prog_meta) &&
+	       __bpf_prog_meta[type].section);
+	return __bpf_prog_meta[type].section;
+}
+
+#ifdef HAVE_ELF
+static int bpf_obj_open(const char *path, enum bpf_prog_type type,
+			const char *sec, __u32 ifindex, bool verbose);
+#else
+static int bpf_obj_open(const char *path, enum bpf_prog_type type,
+			const char *sec, __u32 ifindex, bool verbose)
+{
+	fprintf(stderr, "No ELF library support compiled in.\n");
+	errno = ENOSYS;
+	return -1;
+}
+#endif
+
+static inline __u64 bpf_ptr_to_u64(const void *ptr)
+{
+	return (__u64)(unsigned long)ptr;
+}
+
+static int bpf_map_update(int fd, const void *key, const void *value,
+			  uint64_t flags)
+{
+	union bpf_attr attr = {};
+
+	attr.map_fd = fd;
+	attr.key = bpf_ptr_to_u64(key);
+	attr.value = bpf_ptr_to_u64(value);
+	attr.flags = flags;
+
+	return bpf(BPF_MAP_UPDATE_ELEM, &attr, sizeof(attr));
+}
+
+static int bpf_prog_fd_by_id(uint32_t id)
+{
+	union bpf_attr attr = {};
+
+	attr.prog_id = id;
+
+	return bpf(BPF_PROG_GET_FD_BY_ID, &attr, sizeof(attr));
+}
+
+static int bpf_prog_info_by_fd(int fd, struct bpf_prog_info *info,
+			       uint32_t *info_len)
+{
+	union bpf_attr attr = {};
+	int ret;
+
+	attr.info.bpf_fd = fd;
+	attr.info.info = bpf_ptr_to_u64(info);
+	attr.info.info_len = *info_len;
+
+	*info_len = 0;
+	ret = bpf(BPF_OBJ_GET_INFO_BY_FD, &attr, sizeof(attr));
+	if (!ret)
+		*info_len = attr.info.info_len;
+
+	return ret;
+}
+
+int bpf_dump_prog_info(FILE *f, uint32_t id)
+{
+	struct bpf_prog_info info = {};
+	uint32_t len = sizeof(info);
+	int fd, ret, dump_ok = 0;
+	SPRINT_BUF(tmp);
+
+	open_json_object("prog");
+	print_uint(PRINT_ANY, "id", "id %u ", id);
+
+	fd = bpf_prog_fd_by_id(id);
+	if (fd < 0)
+		goto out;
+
+	ret = bpf_prog_info_by_fd(fd, &info, &len);
+	if (!ret && len) {
+		int jited = !!info.jited_prog_len;
+
+		print_string(PRINT_ANY, "name", "name %s ", info.name);
+		print_string(PRINT_ANY, "tag", "tag %s ",
+			     hexstring_n2a(info.tag, sizeof(info.tag),
+					   tmp, sizeof(tmp)));
+		print_uint(PRINT_JSON, "jited", NULL, jited);
+		if (jited && !is_json_context())
+			fprintf(f, "jited ");
+
+		if (show_details) {
+			if (info.load_time) {
+				/* ns since boottime */
+				print_lluint(PRINT_ANY, "load_time",
+					     "load_time %llu ", info.load_time);
+
+				print_luint(PRINT_ANY, "created_by_uid",
+					    "created_by_uid %lu ",
+					    info.created_by_uid);
+			}
+
+			if (info.btf_id)
+				print_luint(PRINT_ANY, "btf_id", "btf_id %lu ",
+					    info.btf_id);
+		}
+
+		dump_ok = 1;
+	}
+
+	close(fd);
+out:
+	close_json_object();
+	return dump_ok;
+}
+
+static int bpf_parse_string(char *arg, bool from_file, __u16 *bpf_len,
+			    char **bpf_string, bool *need_release,
+			    const char separator)
+{
+	char sp;
+
+	if (from_file) {
+		size_t tmp_len, op_len = sizeof("65535 255 255 4294967295,");
+		char *tmp_string, *pos, c_prev = ' ';
+		FILE *fp;
+		int c;
+
+		tmp_len = sizeof("4096,") + BPF_MAXINSNS * op_len;
+		tmp_string = pos = calloc(1, tmp_len);
+		if (tmp_string == NULL)
+			return -ENOMEM;
+
+		fp = fopen(arg, "r");
+		if (fp == NULL) {
+			perror("Cannot fopen");
+			free(tmp_string);
+			return -ENOENT;
+		}
+
+		while ((c = fgetc(fp)) != EOF) {
+			switch (c) {
+			case '\n':
+				if (c_prev != ',')
+					*(pos++) = ',';
+				c_prev = ',';
+				break;
+			case ' ':
+			case '\t':
+				if (c_prev != ' ')
+					*(pos++) = c;
+				c_prev = ' ';
+				break;
+			default:
+				*(pos++) = c;
+				c_prev = c;
+			}
+			if (pos - tmp_string == tmp_len)
+				break;
+		}
+
+		if (!feof(fp)) {
+			free(tmp_string);
+			fclose(fp);
+			return -E2BIG;
+		}
+
+		fclose(fp);
+		*pos = 0;
+
+		*need_release = true;
+		*bpf_string = tmp_string;
+	} else {
+		*need_release = false;
+		*bpf_string = arg;
+	}
+
+	if (sscanf(*bpf_string, "%hu%c", bpf_len, &sp) != 2 ||
+	    sp != separator) {
+		if (*need_release)
+			free(*bpf_string);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int bpf_ops_parse(int argc, char **argv, struct sock_filter *bpf_ops,
+			 bool from_file)
+{
+	char *bpf_string, *token, separator = ',';
+	int ret = 0, i = 0;
+	bool need_release;
+	__u16 bpf_len = 0;
+
+	if (argc < 1)
+		return -EINVAL;
+	if (bpf_parse_string(argv[0], from_file, &bpf_len, &bpf_string,
+			     &need_release, separator))
+		return -EINVAL;
+	if (bpf_len == 0 || bpf_len > BPF_MAXINSNS) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	token = bpf_string;
+	while ((token = strchr(token, separator)) && (++token)[0]) {
+		if (i >= bpf_len) {
+			fprintf(stderr, "Real program length exceeds encoded length parameter!\n");
+			ret = -EINVAL;
+			goto out;
+		}
+
+		if (sscanf(token, "%hu %hhu %hhu %u,",
+			   &bpf_ops[i].code, &bpf_ops[i].jt,
+			   &bpf_ops[i].jf, &bpf_ops[i].k) != 4) {
+			fprintf(stderr, "Error at instruction %d!\n", i);
+			ret = -EINVAL;
+			goto out;
+		}
+
+		i++;
+	}
+
+	if (i != bpf_len) {
+		fprintf(stderr, "Parsed program length is less than encoded length parameter!\n");
+		ret = -EINVAL;
+		goto out;
+	}
+	ret = bpf_len;
+out:
+	if (need_release)
+		free(bpf_string);
+
+	return ret;
+}
+
+void bpf_print_ops(struct rtattr *bpf_ops, __u16 len)
+{
+	struct sock_filter *ops = RTA_DATA(bpf_ops);
+	int i;
+
+	if (len == 0)
+		return;
+
+	open_json_object("bytecode");
+	print_uint(PRINT_ANY, "length", "bytecode \'%u,", len);
+	open_json_array(PRINT_JSON, "insns");
+
+	for (i = 0; i < len; i++) {
+		open_json_object(NULL);
+		print_hu(PRINT_ANY, "code", "%hu ", ops[i].code);
+		print_hhu(PRINT_ANY, "jt", "%hhu ", ops[i].jt);
+		print_hhu(PRINT_ANY, "jf", "%hhu ", ops[i].jf);
+		if (i == len - 1)
+			print_uint(PRINT_ANY, "k", "%u\'", ops[i].k);
+		else
+			print_uint(PRINT_ANY, "k", "%u,", ops[i].k);
+		close_json_object();
+	}
+
+	close_json_array(PRINT_JSON, NULL);
+	close_json_object();
+}
+
+static void bpf_map_pin_report(const struct bpf_elf_map *pin,
+			       const struct bpf_elf_map *obj)
+{
+	fprintf(stderr, "Map specification differs from pinned file!\n");
+
+	if (obj->type != pin->type)
+		fprintf(stderr, " - Type:         %u (obj) != %u (pin)\n",
+			obj->type, pin->type);
+	if (obj->size_key != pin->size_key)
+		fprintf(stderr, " - Size key:     %u (obj) != %u (pin)\n",
+			obj->size_key, pin->size_key);
+	if (obj->size_value != pin->size_value)
+		fprintf(stderr, " - Size value:   %u (obj) != %u (pin)\n",
+			obj->size_value, pin->size_value);
+	if (obj->max_elem != pin->max_elem)
+		fprintf(stderr, " - Max elems:    %u (obj) != %u (pin)\n",
+			obj->max_elem, pin->max_elem);
+	if (obj->flags != pin->flags)
+		fprintf(stderr, " - Flags:        %#x (obj) != %#x (pin)\n",
+			obj->flags, pin->flags);
+
+	fprintf(stderr, "\n");
+}
+
+struct bpf_prog_data {
+	unsigned int type;
+	unsigned int jited;
+};
+
+struct bpf_map_ext {
+	struct bpf_prog_data owner;
+	unsigned int btf_id_key;
+	unsigned int btf_id_val;
+};
+
+static int bpf_derive_elf_map_from_fdinfo(int fd, struct bpf_elf_map *map,
+					  struct bpf_map_ext *ext)
+{
+	unsigned int val, owner_type = 0, owner_jited = 0;
+	char file[PATH_MAX], buff[4096];
+	FILE *fp;
+
+	snprintf(file, sizeof(file), "/proc/%d/fdinfo/%d", getpid(), fd);
+	memset(map, 0, sizeof(*map));
+
+	fp = fopen(file, "r");
+	if (!fp) {
+		fprintf(stderr, "No procfs support?!\n");
+		return -EIO;
+	}
+
+	while (fgets(buff, sizeof(buff), fp)) {
+		if (sscanf(buff, "map_type:\t%u", &val) == 1)
+			map->type = val;
+		else if (sscanf(buff, "key_size:\t%u", &val) == 1)
+			map->size_key = val;
+		else if (sscanf(buff, "value_size:\t%u", &val) == 1)
+			map->size_value = val;
+		else if (sscanf(buff, "max_entries:\t%u", &val) == 1)
+			map->max_elem = val;
+		else if (sscanf(buff, "map_flags:\t%i", &val) == 1)
+			map->flags = val;
+		else if (sscanf(buff, "owner_prog_type:\t%i", &val) == 1)
+			owner_type = val;
+		else if (sscanf(buff, "owner_jited:\t%i", &val) == 1)
+			owner_jited = val;
+	}
+
+	fclose(fp);
+	if (ext) {
+		memset(ext, 0, sizeof(*ext));
+		ext->owner.type  = owner_type;
+		ext->owner.jited = owner_jited;
+	}
+
+	return 0;
+}
+
+static int bpf_map_selfcheck_pinned(int fd, const struct bpf_elf_map *map,
+				    struct bpf_map_ext *ext, int length,
+				    enum bpf_prog_type type)
+{
+	struct bpf_elf_map tmp, zero = {};
+	int ret;
+
+	ret = bpf_derive_elf_map_from_fdinfo(fd, &tmp, ext);
+	if (ret < 0)
+		return ret;
+
+	/* The decision to reject this is on kernel side eventually, but
+	 * at least give the user a chance to know what's wrong.
+	 */
+	if (ext->owner.type && ext->owner.type != type)
+		fprintf(stderr, "Program array map owner types differ: %u (obj) != %u (pin)\n",
+			type, ext->owner.type);
+
+	if (!memcmp(&tmp, map, length)) {
+		return 0;
+	} else {
+		/* If kernel doesn't have eBPF-related fdinfo, we cannot do much,
+		 * so just accept it. We know we do have an eBPF fd and in this
+		 * case, everything is 0. It is guaranteed that no such map exists
+		 * since map type of 0 is unloadable BPF_MAP_TYPE_UNSPEC.
+		 */
+		if (!memcmp(&tmp, &zero, length))
+			return 0;
+
+		bpf_map_pin_report(&tmp, map);
+		return -EINVAL;
+	}
+}
+
+static int bpf_mnt_fs(const char *target)
+{
+	bool bind_done = false;
+
+	while (mount("", target, "none", MS_PRIVATE | MS_REC, NULL)) {
+		if (errno != EINVAL || bind_done) {
+			fprintf(stderr, "mount --make-private %s failed: %s\n",
+				target,	strerror(errno));
+			return -1;
+		}
+
+		if (mount(target, target, "none", MS_BIND, NULL)) {
+			fprintf(stderr, "mount --bind %s %s failed: %s\n",
+				target,	target, strerror(errno));
+			return -1;
+		}
+
+		bind_done = true;
+	}
+
+	if (mount("bpf", target, "bpf", 0, "mode=0700")) {
+		fprintf(stderr, "mount -t bpf bpf %s failed: %s\n",
+			target,	strerror(errno));
+		return -1;
+	}
+
+	return 0;
+}
+
+static int bpf_mnt_check_target(const char *target)
+{
+	int ret;
+
+	ret = mkdir(target, S_IRWXU);
+	if (ret) {
+		if (errno == EEXIST)
+			return 0;
+		fprintf(stderr, "mkdir %s failed: %s\n", target,
+			strerror(errno));
+	}
+
+	return ret;
+}
+
+static int bpf_valid_mntpt(const char *mnt, unsigned long magic)
+{
+	struct statfs st_fs;
+
+	if (statfs(mnt, &st_fs) < 0)
+		return -ENOENT;
+	if ((unsigned long)st_fs.f_type != magic)
+		return -ENOENT;
+
+	return 0;
+}
+
+static const char *bpf_find_mntpt_single(unsigned long magic, char *mnt,
+					 int len, const char *mntpt)
+{
+	int ret;
+
+	ret = bpf_valid_mntpt(mntpt, magic);
+	if (!ret) {
+		strlcpy(mnt, mntpt, len);
+		return mnt;
+	}
+
+	return NULL;
+}
+
+static const char *bpf_find_mntpt(const char *fstype, unsigned long magic,
+				  char *mnt, int len,
+				  const char * const *known_mnts)
+{
+	const char * const *ptr;
+	char type[100];
+	FILE *fp;
+
+	if (known_mnts) {
+		ptr = known_mnts;
+		while (*ptr) {
+			if (bpf_find_mntpt_single(magic, mnt, len, *ptr))
+				return mnt;
+			ptr++;
+		}
+	}
+
+	if (len != PATH_MAX)
+		return NULL;
+
+	fp = fopen("/proc/mounts", "r");
+	if (fp == NULL)
+		return NULL;
+
+	while (fscanf(fp, "%*s %" textify(PATH_MAX) "s %99s %*s %*d %*d\n",
+		      mnt, type) == 2) {
+		if (strcmp(type, fstype) == 0)
+			break;
+	}
+
+	fclose(fp);
+	if (strcmp(type, fstype) != 0)
+		return NULL;
+
+	return mnt;
+}
+
+int bpf_trace_pipe(void)
+{
+	char tracefs_mnt[PATH_MAX] = TRACE_DIR_MNT;
+	static const char * const tracefs_known_mnts[] = {
+		TRACE_DIR_MNT,
+		"/sys/kernel/debug/tracing",
+		"/tracing",
+		"/trace",
+		0,
+	};
+	int fd_in, fd_out = STDERR_FILENO;
+	char tpipe[PATH_MAX];
+	const char *mnt;
+
+	mnt = bpf_find_mntpt("tracefs", TRACEFS_MAGIC, tracefs_mnt,
+			     sizeof(tracefs_mnt), tracefs_known_mnts);
+	if (!mnt) {
+		fprintf(stderr, "tracefs not mounted?\n");
+		return -1;
+	}
+
+	snprintf(tpipe, sizeof(tpipe), "%s/trace_pipe", mnt);
+
+	fd_in = open(tpipe, O_RDONLY);
+	if (fd_in < 0)
+		return -1;
+
+	fprintf(stderr, "Running! Hang up with ^C!\n\n");
+	while (1) {
+		static char buff[4096];
+		ssize_t ret;
+
+		ret = read(fd_in, buff, sizeof(buff));
+		if (ret > 0 && write(fd_out, buff, ret) == ret)
+			continue;
+		break;
+	}
+
+	close(fd_in);
+	return -1;
+}
+
+static int bpf_gen_global(const char *bpf_sub_dir)
+{
+	char bpf_glo_dir[PATH_MAX];
+	int ret;
+
+	snprintf(bpf_glo_dir, sizeof(bpf_glo_dir), "%s/%s/",
+		 bpf_sub_dir, BPF_DIR_GLOBALS);
+
+	ret = mkdir(bpf_glo_dir, S_IRWXU);
+	if (ret && errno != EEXIST) {
+		fprintf(stderr, "mkdir %s failed: %s\n", bpf_glo_dir,
+			strerror(errno));
+		return ret;
+	}
+
+	return 0;
+}
+
+static int bpf_gen_master(const char *base, const char *name)
+{
+	char bpf_sub_dir[PATH_MAX + NAME_MAX + 1];
+	int ret;
+
+	snprintf(bpf_sub_dir, sizeof(bpf_sub_dir), "%s%s/", base, name);
+
+	ret = mkdir(bpf_sub_dir, S_IRWXU);
+	if (ret && errno != EEXIST) {
+		fprintf(stderr, "mkdir %s failed: %s\n", bpf_sub_dir,
+			strerror(errno));
+		return ret;
+	}
+
+	return bpf_gen_global(bpf_sub_dir);
+}
+
+static int bpf_slave_via_bind_mnt(const char *full_name,
+				  const char *full_link)
+{
+	int ret;
+
+	ret = mkdir(full_name, S_IRWXU);
+	if (ret) {
+		assert(errno != EEXIST);
+		fprintf(stderr, "mkdir %s failed: %s\n", full_name,
+			strerror(errno));
+		return ret;
+	}
+
+	ret = mount(full_link, full_name, "none", MS_BIND, NULL);
+	if (ret) {
+		rmdir(full_name);
+		fprintf(stderr, "mount --bind %s %s failed: %s\n",
+			full_link, full_name, strerror(errno));
+	}
+
+	return ret;
+}
+
+static int bpf_gen_slave(const char *base, const char *name,
+			 const char *link)
+{
+	char bpf_lnk_dir[PATH_MAX + NAME_MAX + 1];
+	char bpf_sub_dir[PATH_MAX + NAME_MAX];
+	struct stat sb = {};
+	int ret;
+
+	snprintf(bpf_lnk_dir, sizeof(bpf_lnk_dir), "%s%s/", base, link);
+	snprintf(bpf_sub_dir, sizeof(bpf_sub_dir), "%s%s",  base, name);
+
+	ret = symlink(bpf_lnk_dir, bpf_sub_dir);
+	if (ret) {
+		if (errno != EEXIST) {
+			if (errno != EPERM) {
+				fprintf(stderr, "symlink %s failed: %s\n",
+					bpf_sub_dir, strerror(errno));
+				return ret;
+			}
+
+			return bpf_slave_via_bind_mnt(bpf_sub_dir,
+						      bpf_lnk_dir);
+		}
+
+		ret = lstat(bpf_sub_dir, &sb);
+		if (ret) {
+			fprintf(stderr, "lstat %s failed: %s\n",
+				bpf_sub_dir, strerror(errno));
+			return ret;
+		}
+
+		if ((sb.st_mode & S_IFMT) != S_IFLNK)
+			return bpf_gen_global(bpf_sub_dir);
+	}
+
+	return 0;
+}
+
+static int bpf_gen_hierarchy(const char *base)
+{
+	int ret, i;
+
+	ret = bpf_gen_master(base, bpf_prog_to_subdir(__bpf_types[0]));
+	for (i = 1; i < ARRAY_SIZE(__bpf_types) && !ret; i++)
+		ret = bpf_gen_slave(base,
+				    bpf_prog_to_subdir(__bpf_types[i]),
+				    bpf_prog_to_subdir(__bpf_types[0]));
+	return ret;
+}
+
+static const char *bpf_get_work_dir(enum bpf_prog_type type)
+{
+	static char bpf_tmp[PATH_MAX] = BPF_DIR_MNT;
+	static char bpf_wrk_dir[PATH_MAX];
+	static const char *mnt;
+	static bool bpf_mnt_cached;
+	const char *mnt_env = getenv(BPF_ENV_MNT);
+	static const char * const bpf_known_mnts[] = {
+		BPF_DIR_MNT,
+		"/bpf",
+		0,
+	};
+	int ret;
+
+	if (bpf_mnt_cached) {
+		const char *out = mnt;
+
+		if (out && type) {
+			snprintf(bpf_tmp, sizeof(bpf_tmp), "%s%s/",
+				 out, bpf_prog_to_subdir(type));
+			out = bpf_tmp;
+		}
+		return out;
+	}
+
+	if (mnt_env)
+		mnt = bpf_find_mntpt_single(BPF_FS_MAGIC, bpf_tmp,
+					    sizeof(bpf_tmp), mnt_env);
+	else
+		mnt = bpf_find_mntpt("bpf", BPF_FS_MAGIC, bpf_tmp,
+				     sizeof(bpf_tmp), bpf_known_mnts);
+	if (!mnt) {
+		mnt = mnt_env ? : BPF_DIR_MNT;
+		ret = bpf_mnt_check_target(mnt);
+		if (!ret)
+			ret = bpf_mnt_fs(mnt);
+		if (ret) {
+			mnt = NULL;
+			goto out;
+		}
+	}
+
+	ret = snprintf(bpf_wrk_dir, sizeof(bpf_wrk_dir), "%s/", mnt);
+	if (ret < 0 || ret >= sizeof(bpf_wrk_dir)) {
+		mnt = NULL;
+		goto out;
+	}
+
+	ret = bpf_gen_hierarchy(bpf_wrk_dir);
+	if (ret) {
+		mnt = NULL;
+		goto out;
+	}
+
+	mnt = bpf_wrk_dir;
+out:
+	bpf_mnt_cached = true;
+	return mnt;
+}
+
+static int bpf_obj_get(const char *pathname, enum bpf_prog_type type)
+{
+	union bpf_attr attr = {};
+	char tmp[PATH_MAX];
+
+	if (strlen(pathname) > 2 && pathname[0] == 'm' &&
+	    pathname[1] == ':' && bpf_get_work_dir(type)) {
+		snprintf(tmp, sizeof(tmp), "%s/%s",
+			 bpf_get_work_dir(type), pathname + 2);
+		pathname = tmp;
+	}
+
+	attr.pathname = bpf_ptr_to_u64(pathname);
+
+	return bpf(BPF_OBJ_GET, &attr, sizeof(attr));
+}
+
+static int bpf_obj_pinned(const char *pathname, enum bpf_prog_type type)
+{
+	int prog_fd = bpf_obj_get(pathname, type);
+
+	if (prog_fd < 0)
+		fprintf(stderr, "Couldn\'t retrieve pinned program \'%s\': %s\n",
+			pathname, strerror(errno));
+	return prog_fd;
+}
+
+static int bpf_do_parse(struct bpf_cfg_in *cfg, const bool *opt_tbl)
+{
+	const char *file, *section, *uds_name, *prog_name;
+	bool verbose = false;
+	int i, ret, argc;
+	char **argv;
+
+	argv = cfg->argv;
+	argc = cfg->argc;
+
+	if (opt_tbl[CBPF_BYTECODE] &&
+	    (matches(*argv, "bytecode") == 0 ||
+	     strcmp(*argv, "bc") == 0)) {
+		cfg->mode = CBPF_BYTECODE;
+	} else if (opt_tbl[CBPF_FILE] &&
+		   (matches(*argv, "bytecode-file") == 0 ||
+		    strcmp(*argv, "bcf") == 0)) {
+		cfg->mode = CBPF_FILE;
+	} else if (opt_tbl[EBPF_OBJECT] &&
+		   (matches(*argv, "object-file") == 0 ||
+		    strcmp(*argv, "obj") == 0)) {
+		cfg->mode = EBPF_OBJECT;
+	} else if (opt_tbl[EBPF_PINNED] &&
+		   (matches(*argv, "object-pinned") == 0 ||
+		    matches(*argv, "pinned") == 0 ||
+		    matches(*argv, "fd") == 0)) {
+		cfg->mode = EBPF_PINNED;
+	} else {
+		fprintf(stderr, "What mode is \"%s\"?\n", *argv);
+		return -1;
+	}
+
+	NEXT_ARG();
+	file = section = uds_name = prog_name = NULL;
+	if (cfg->mode == EBPF_OBJECT || cfg->mode == EBPF_PINNED) {
+		file = *argv;
+		NEXT_ARG_FWD();
+
+		if (cfg->type == BPF_PROG_TYPE_UNSPEC) {
+			if (argc > 0 && matches(*argv, "type") == 0) {
+				NEXT_ARG();
+				for (i = 0; i < ARRAY_SIZE(__bpf_prog_meta);
+				     i++) {
+					if (!__bpf_prog_meta[i].type)
+						continue;
+					if (!matches(*argv,
+						     __bpf_prog_meta[i].type)) {
+						cfg->type = i;
+						break;
+					}
+				}
+
+				if (cfg->type == BPF_PROG_TYPE_UNSPEC) {
+					fprintf(stderr, "What type is \"%s\"?\n",
+						*argv);
+					return -1;
+				}
+				NEXT_ARG_FWD();
+			} else {
+				cfg->type = BPF_PROG_TYPE_SCHED_CLS;
+			}
+		}
+
+		section = bpf_prog_to_default_section(cfg->type);
+		if (argc > 0 && matches(*argv, "section") == 0) {
+			NEXT_ARG();
+			section = *argv;
+			NEXT_ARG_FWD();
+		}
+
+		if (argc > 0 && strcmp(*argv, "program") == 0) {
+			NEXT_ARG();
+			prog_name = *argv;
+			NEXT_ARG_FWD();
+		}
+
+		if (__bpf_prog_meta[cfg->type].may_uds_export) {
+			uds_name = getenv(BPF_ENV_UDS);
+			if (argc > 0 && !uds_name &&
+			    matches(*argv, "export") == 0) {
+				NEXT_ARG();
+				uds_name = *argv;
+				NEXT_ARG_FWD();
+			}
+		}
+
+		if (argc > 0 && matches(*argv, "verbose") == 0) {
+			verbose = true;
+			NEXT_ARG_FWD();
+		}
+
+		PREV_ARG();
+	}
+
+	if (cfg->mode == CBPF_BYTECODE || cfg->mode == CBPF_FILE) {
+		ret = bpf_ops_parse(argc, argv, cfg->opcodes,
+				    cfg->mode == CBPF_FILE);
+		cfg->n_opcodes = ret;
+	} else if (cfg->mode == EBPF_OBJECT) {
+		ret = 0; /* program will be loaded by load stage */
+	} else if (cfg->mode == EBPF_PINNED) {
+		ret = bpf_obj_pinned(file, cfg->type);
+		cfg->prog_fd = ret;
+	} else {
+		return -1;
+	}
+
+	cfg->object  = file;
+	cfg->section = section;
+	cfg->uds     = uds_name;
+	cfg->argc    = argc;
+	cfg->argv    = argv;
+	cfg->verbose = verbose;
+	cfg->prog_name = prog_name;
+
+	return ret;
+}
+
+static int bpf_do_load(struct bpf_cfg_in *cfg)
+{
+	if (cfg->mode == EBPF_OBJECT) {
+#ifdef HAVE_LIBBPF
+		return iproute2_load_libbpf(cfg);
+#endif
+		cfg->prog_fd = bpf_obj_open(cfg->object, cfg->type,
+					    cfg->section, cfg->ifindex,
+					    cfg->verbose);
+		return cfg->prog_fd;
+	}
+	return 0;
+}
+
+int bpf_load_common(struct bpf_cfg_in *cfg, const struct bpf_cfg_ops *ops,
+		    void *nl)
+{
+	char annotation[256];
+	int ret;
+
+	ret = bpf_do_load(cfg);
+	if (ret < 0)
+		return ret;
+
+	if (cfg->mode == CBPF_BYTECODE || cfg->mode == CBPF_FILE)
+		ops->cbpf_cb(nl, cfg->opcodes, cfg->n_opcodes);
+	if (cfg->mode == EBPF_OBJECT || cfg->mode == EBPF_PINNED) {
+		snprintf(annotation, sizeof(annotation), "%s:[%s]",
+			 basename(cfg->object), cfg->mode == EBPF_PINNED ?
+			 "*fsobj" : cfg->section);
+		ops->ebpf_cb(nl, cfg->prog_fd, annotation);
+	}
+
+	return 0;
+}
+
+int bpf_parse_common(struct bpf_cfg_in *cfg, const struct bpf_cfg_ops *ops)
+{
+	bool opt_tbl[BPF_MODE_MAX] = {};
+
+	if (ops->cbpf_cb) {
+		opt_tbl[CBPF_BYTECODE] = true;
+		opt_tbl[CBPF_FILE]     = true;
+	}
+
+	if (ops->ebpf_cb) {
+		opt_tbl[EBPF_OBJECT]   = true;
+		opt_tbl[EBPF_PINNED]   = true;
+	}
+
+	return bpf_do_parse(cfg, opt_tbl);
+}
+
+int bpf_parse_and_load_common(struct bpf_cfg_in *cfg,
+			      const struct bpf_cfg_ops *ops, void *nl)
+{
+	int ret;
+
+	ret = bpf_parse_common(cfg, ops);
+	if (ret < 0)
+		return ret;
+
+	return bpf_load_common(cfg, ops, nl);
+}
+
+int bpf_graft_map(const char *map_path, uint32_t *key, int argc, char **argv)
+{
+	const bool opt_tbl[BPF_MODE_MAX] = {
+		[EBPF_OBJECT]	= true,
+		[EBPF_PINNED]	= true,
+	};
+	const struct bpf_elf_map test = {
+		.type		= BPF_MAP_TYPE_PROG_ARRAY,
+		.size_key	= sizeof(int),
+		.size_value	= sizeof(int),
+	};
+	struct bpf_cfg_in cfg = {
+		.type		= BPF_PROG_TYPE_UNSPEC,
+		.argc		= argc,
+		.argv		= argv,
+	};
+	struct bpf_map_ext ext = {};
+	int ret, prog_fd, map_fd;
+	uint32_t map_key;
+
+	ret = bpf_do_parse(&cfg, opt_tbl);
+	if (ret < 0)
+		return ret;
+
+	ret = bpf_do_load(&cfg);
+	if (ret < 0)
+		return ret;
+
+	prog_fd = cfg.prog_fd;
+
+	if (key) {
+		map_key = *key;
+	} else {
+		ret = sscanf(cfg.section, "%*i/%i", &map_key);
+		if (ret != 1) {
+			fprintf(stderr, "Couldn\'t infer map key from section name! Please provide \'key\' argument!\n");
+			ret = -EINVAL;
+			goto out_prog;
+		}
+	}
+
+	map_fd = bpf_obj_get(map_path, cfg.type);
+	if (map_fd < 0) {
+		fprintf(stderr, "Couldn\'t retrieve pinned map \'%s\': %s\n",
+			map_path, strerror(errno));
+		ret = map_fd;
+		goto out_prog;
+	}
+
+	ret = bpf_map_selfcheck_pinned(map_fd, &test, &ext,
+				       offsetof(struct bpf_elf_map, max_elem),
+				       cfg.type);
+	if (ret < 0) {
+		fprintf(stderr, "Map \'%s\' self-check failed!\n", map_path);
+		goto out_map;
+	}
+
+	ret = bpf_map_update(map_fd, &map_key, &prog_fd, BPF_ANY);
+	if (ret < 0)
+		fprintf(stderr, "Map update failed: %s\n", strerror(errno));
+out_map:
+	close(map_fd);
+out_prog:
+	close(prog_fd);
+	return ret;
+}
+
+int bpf_prog_attach_fd(int prog_fd, int target_fd, enum bpf_attach_type type)
+{
+	union bpf_attr attr = {};
+
+	attr.target_fd = target_fd;
+	attr.attach_bpf_fd = prog_fd;
+	attr.attach_type = type;
+
+	return bpf(BPF_PROG_ATTACH, &attr, sizeof(attr));
+}
+
+int bpf_prog_detach_fd(int target_fd, enum bpf_attach_type type)
+{
+	union bpf_attr attr = {};
+
+	attr.target_fd = target_fd;
+	attr.attach_type = type;
+
+	return bpf(BPF_PROG_DETACH, &attr, sizeof(attr));
+}
+
+int bpf_prog_load_dev(enum bpf_prog_type type, const struct bpf_insn *insns,
+		      size_t size_insns, const char *license, __u32 ifindex,
+		      char *log, size_t size_log)
+{
+	union bpf_attr attr = {};
+
+	attr.prog_type = type;
+	attr.insns = bpf_ptr_to_u64(insns);
+	attr.insn_cnt = size_insns / sizeof(struct bpf_insn);
+	attr.license = bpf_ptr_to_u64(license);
+	attr.prog_ifindex = ifindex;
+
+	if (size_log > 0) {
+		attr.log_buf = bpf_ptr_to_u64(log);
+		attr.log_size = size_log;
+		attr.log_level = 1;
+	}
+
+	return bpf(BPF_PROG_LOAD, &attr, sizeof(attr));
+}
+
+int bpf_program_load(enum bpf_prog_type type, const struct bpf_insn *insns,
+		     size_t size_insns, const char *license, char *log,
+		     size_t size_log)
+{
+	return bpf_prog_load_dev(type, insns, size_insns, license, 0, log, size_log);
+}
+
+#ifdef HAVE_ELF
+struct bpf_elf_prog {
+	enum bpf_prog_type	type;
+	struct bpf_insn		*insns;
+	unsigned int		insns_num;
+	size_t			size;
+	const char		*license;
+};
+
+struct bpf_hash_entry {
+	unsigned int		pinning;
+	const char		*subpath;
+	struct bpf_hash_entry	*next;
+};
+
+struct bpf_config {
+	unsigned int		jit_enabled;
+};
+
+struct bpf_btf {
+	const struct btf_header	*hdr;
+	const void		*raw;
+	const char		*strings;
+	const struct btf_type	**types;
+	int			types_num;
+};
+
+struct bpf_elf_ctx {
+	struct bpf_config	cfg;
+	Elf			*elf_fd;
+	GElf_Ehdr		elf_hdr;
+	Elf_Data		*sym_tab;
+	Elf_Data		*str_tab;
+	Elf_Data		*btf_data;
+	char			obj_uid[64];
+	int			obj_fd;
+	int			btf_fd;
+	int			map_fds[ELF_MAX_MAPS];
+	struct bpf_elf_map	maps[ELF_MAX_MAPS];
+	struct bpf_map_ext	maps_ext[ELF_MAX_MAPS];
+	struct bpf_elf_prog	prog_text;
+	struct bpf_btf		btf;
+	int			sym_num;
+	int			map_num;
+	int			map_len;
+	bool			*sec_done;
+	int			sec_maps;
+	int			sec_text;
+	int			sec_btf;
+	char			license[ELF_MAX_LICENSE_LEN];
+	enum bpf_prog_type	type;
+	__u32			ifindex;
+	bool			verbose;
+	bool			noafalg;
+	struct bpf_elf_st	stat;
+	struct bpf_hash_entry	*ht[256];
+	char			*log;
+	size_t			log_size;
+};
+
+struct bpf_elf_sec_data {
+	GElf_Shdr		sec_hdr;
+	Elf_Data		*sec_data;
+	const char		*sec_name;
+};
+
+struct bpf_map_data {
+	int			*fds;
+	const char		*obj;
+	struct bpf_elf_st	*st;
+	struct bpf_elf_map	*ent;
+};
+
+static bool bpf_log_has_data(struct bpf_elf_ctx *ctx)
+{
+	return ctx->log && ctx->log[0];
+}
+
+static __check_format_string(2, 3) void
+bpf_dump_error(struct bpf_elf_ctx *ctx, const char *format, ...)
+{
+	va_list vl;
+
+	va_start(vl, format);
+	vfprintf(stderr, format, vl);
+	va_end(vl);
+
+	if (bpf_log_has_data(ctx)) {
+		if (ctx->verbose) {
+			fprintf(stderr, "%s\n", ctx->log);
+		} else {
+			unsigned int off = 0, len = strlen(ctx->log);
+
+			if (len > BPF_MAX_LOG) {
+				off = len - BPF_MAX_LOG;
+				fprintf(stderr, "Skipped %u bytes, use \'verb\' option for the full verbose log.\n[...]\n",
+					off);
+			}
+			fprintf(stderr, "%s\n", ctx->log + off);
+		}
+
+		memset(ctx->log, 0, ctx->log_size);
+	}
+}
+
+static int bpf_log_realloc(struct bpf_elf_ctx *ctx)
+{
+	const size_t log_max = UINT_MAX >> 8;
+	size_t log_size = ctx->log_size;
+	char *ptr;
+
+	if (!ctx->log) {
+		log_size = 65536;
+	} else if (log_size < log_max) {
+		log_size <<= 1;
+		if (log_size > log_max)
+			log_size = log_max;
+	} else {
+		return -EINVAL;
+	}
+
+	ptr = realloc(ctx->log, log_size);
+	if (!ptr)
+		return -ENOMEM;
+
+	ptr[0] = 0;
+	ctx->log = ptr;
+	ctx->log_size = log_size;
+
+	return 0;
+}
+
+static int bpf_map_create(enum bpf_map_type type, uint32_t size_key,
+			  uint32_t size_value, uint32_t max_elem,
+			  uint32_t flags, int inner_fd, int btf_fd,
+			  uint32_t ifindex, uint32_t btf_id_key,
+			  uint32_t btf_id_val)
+{
+	union bpf_attr attr = {};
+
+	attr.map_type = type;
+	attr.key_size = size_key;
+	attr.value_size = inner_fd ? sizeof(int) : size_value;
+	attr.max_entries = max_elem;
+	attr.map_flags = flags;
+	attr.inner_map_fd = inner_fd;
+	attr.map_ifindex = ifindex;
+	attr.btf_fd = btf_fd;
+	attr.btf_key_type_id = btf_id_key;
+	attr.btf_value_type_id = btf_id_val;
+
+	return bpf(BPF_MAP_CREATE, &attr, sizeof(attr));
+}
+
+static int bpf_btf_load(void *btf, size_t size_btf,
+			char *log, size_t size_log)
+{
+	union bpf_attr attr = {};
+
+	attr.btf = bpf_ptr_to_u64(btf);
+	attr.btf_size = size_btf;
+
+	if (size_log > 0) {
+		attr.btf_log_buf = bpf_ptr_to_u64(log);
+		attr.btf_log_size = size_log;
+		attr.btf_log_level = 1;
+	}
+
+	return bpf(BPF_BTF_LOAD, &attr, sizeof(attr));
+}
+
+static int bpf_obj_pin(int fd, const char *pathname)
+{
+	union bpf_attr attr = {};
+
+	attr.pathname = bpf_ptr_to_u64(pathname);
+	attr.bpf_fd = fd;
+
+	return bpf(BPF_OBJ_PIN, &attr, sizeof(attr));
+}
+
+static int bpf_obj_hash(const char *object, uint8_t *out, size_t len)
+{
+	struct sockaddr_alg alg = {
+		.salg_family	= AF_ALG,
+		.salg_type	= "hash",
+		.salg_name	= "sha1",
+	};
+	int ret, cfd, ofd, ffd;
+	struct stat stbuff;
+	ssize_t size;
+
+	if (!object || len != 20)
+		return -EINVAL;
+
+	cfd = socket(AF_ALG, SOCK_SEQPACKET, 0);
+	if (cfd < 0)
+		return cfd;
+
+	ret = bind(cfd, (struct sockaddr *)&alg, sizeof(alg));
+	if (ret < 0)
+		goto out_cfd;
+
+	ofd = accept(cfd, NULL, 0);
+	if (ofd < 0) {
+		ret = ofd;
+		goto out_cfd;
+	}
+
+	ffd = open(object, O_RDONLY);
+	if (ffd < 0) {
+		fprintf(stderr, "Error opening object %s: %s\n",
+			object, strerror(errno));
+		ret = ffd;
+		goto out_ofd;
+	}
+
+	ret = fstat(ffd, &stbuff);
+	if (ret < 0) {
+		fprintf(stderr, "Error doing fstat: %s\n",
+			strerror(errno));
+		goto out_ffd;
+	}
+
+	size = sendfile(ofd, ffd, NULL, stbuff.st_size);
+	if (size != stbuff.st_size) {
+		fprintf(stderr, "Error from sendfile (%zd vs %zu bytes): %s\n",
+			size, stbuff.st_size, strerror(errno));
+		ret = -1;
+		goto out_ffd;
+	}
+
+	size = read(ofd, out, len);
+	if (size != len) {
+		fprintf(stderr, "Error from read (%zd vs %zu bytes): %s\n",
+			size, len, strerror(errno));
+		ret = -1;
+	} else {
+		ret = 0;
+	}
+out_ffd:
+	close(ffd);
+out_ofd:
+	close(ofd);
+out_cfd:
+	close(cfd);
+	return ret;
+}
+
+static void bpf_init_env(void)
+{
+	struct rlimit limit = {
+		.rlim_cur = RLIM_INFINITY,
+		.rlim_max = RLIM_INFINITY,
+	};
+
+	/* Don't bother in case we fail! */
+	setrlimit(RLIMIT_MEMLOCK, &limit);
+
+	if (!bpf_get_work_dir(BPF_PROG_TYPE_UNSPEC))
+		fprintf(stderr, "Continuing without mounted eBPF fs. Too old kernel?\n");
+}
+
+static const char *bpf_custom_pinning(const struct bpf_elf_ctx *ctx,
+				      uint32_t pinning)
+{
+	struct bpf_hash_entry *entry;
+
+	entry = ctx->ht[pinning & (ARRAY_SIZE(ctx->ht) - 1)];
+	while (entry && entry->pinning != pinning)
+		entry = entry->next;
+
+	return entry ? entry->subpath : NULL;
+}
+
+static bool bpf_no_pinning(const struct bpf_elf_ctx *ctx,
+			   uint32_t pinning)
+{
+	switch (pinning) {
+	case PIN_OBJECT_NS:
+	case PIN_GLOBAL_NS:
+		return false;
+	case PIN_NONE:
+		return true;
+	default:
+		return !bpf_custom_pinning(ctx, pinning);
+	}
+}
+
+static void bpf_make_pathname(char *pathname, size_t len, const char *name,
+			      const struct bpf_elf_ctx *ctx, uint32_t pinning)
+{
+	switch (pinning) {
+	case PIN_OBJECT_NS:
+		snprintf(pathname, len, "%s/%s/%s",
+			 bpf_get_work_dir(ctx->type),
+			 ctx->obj_uid, name);
+		break;
+	case PIN_GLOBAL_NS:
+		snprintf(pathname, len, "%s/%s/%s",
+			 bpf_get_work_dir(ctx->type),
+			 BPF_DIR_GLOBALS, name);
+		break;
+	default:
+		snprintf(pathname, len, "%s/../%s/%s",
+			 bpf_get_work_dir(ctx->type),
+			 bpf_custom_pinning(ctx, pinning), name);
+		break;
+	}
+}
+
+static int bpf_probe_pinned(const char *name, const struct bpf_elf_ctx *ctx,
+			    uint32_t pinning)
+{
+	char pathname[PATH_MAX];
+
+	if (bpf_no_pinning(ctx, pinning) || !bpf_get_work_dir(ctx->type))
+		return 0;
+
+	bpf_make_pathname(pathname, sizeof(pathname), name, ctx, pinning);
+	return bpf_obj_get(pathname, ctx->type);
+}
+
+static int bpf_make_obj_path(const struct bpf_elf_ctx *ctx)
+{
+	char tmp[PATH_MAX];
+	int ret;
+
+	snprintf(tmp, sizeof(tmp), "%s/%s", bpf_get_work_dir(ctx->type),
+		 ctx->obj_uid);
+
+	ret = mkdir(tmp, S_IRWXU);
+	if (ret && errno != EEXIST) {
+		fprintf(stderr, "mkdir %s failed: %s\n", tmp, strerror(errno));
+		return ret;
+	}
+
+	return 0;
+}
+
+static int bpf_make_custom_path(const struct bpf_elf_ctx *ctx,
+				const char *todo)
+{
+	char tmp[PATH_MAX], rem[PATH_MAX], *sub;
+	int ret;
+
+	snprintf(tmp, sizeof(tmp), "%s/../", bpf_get_work_dir(ctx->type));
+	snprintf(rem, sizeof(rem), "%s/", todo);
+	sub = strtok(rem, "/");
+
+	while (sub) {
+		if (strlen(tmp) + strlen(sub) + 2 > PATH_MAX)
+			return -EINVAL;
+
+		strcat(tmp, sub);
+		strcat(tmp, "/");
+
+		ret = mkdir(tmp, S_IRWXU);
+		if (ret && errno != EEXIST) {
+			fprintf(stderr, "mkdir %s failed: %s\n", tmp,
+				strerror(errno));
+			return ret;
+		}
+
+		sub = strtok(NULL, "/");
+	}
+
+	return 0;
+}
+
+static int bpf_place_pinned(int fd, const char *name,
+			    const struct bpf_elf_ctx *ctx, uint32_t pinning)
+{
+	char pathname[PATH_MAX];
+	const char *tmp;
+	int ret = 0;
+
+	if (bpf_no_pinning(ctx, pinning) || !bpf_get_work_dir(ctx->type))
+		return 0;
+
+	if (pinning == PIN_OBJECT_NS)
+		ret = bpf_make_obj_path(ctx);
+	else if ((tmp = bpf_custom_pinning(ctx, pinning)))
+		ret = bpf_make_custom_path(ctx, tmp);
+	if (ret < 0)
+		return ret;
+
+	bpf_make_pathname(pathname, sizeof(pathname), name, ctx, pinning);
+	return bpf_obj_pin(fd, pathname);
+}
+
+static void bpf_prog_report(int fd, const char *section,
+			    const struct bpf_elf_prog *prog,
+			    struct bpf_elf_ctx *ctx)
+{
+	unsigned int insns = prog->size / sizeof(struct bpf_insn);
+
+	fprintf(stderr, "\nProg section \'%s\' %s%s (%d)!\n", section,
+		fd < 0 ? "rejected: " : "loaded",
+		fd < 0 ? strerror(errno) : "",
+		fd < 0 ? errno : fd);
+
+	fprintf(stderr, " - Type:         %u\n", prog->type);
+	fprintf(stderr, " - Instructions: %u (%u over limit)\n",
+		insns, insns > BPF_MAXINSNS ? insns - BPF_MAXINSNS : 0);
+	fprintf(stderr, " - License:      %s\n\n", prog->license);
+
+	bpf_dump_error(ctx, "Verifier analysis:\n\n");
+}
+
+static int bpf_prog_attach(const char *section,
+			   const struct bpf_elf_prog *prog,
+			   struct bpf_elf_ctx *ctx)
+{
+	int tries = 0, fd;
+retry:
+	errno = 0;
+	fd = bpf_prog_load_dev(prog->type, prog->insns, prog->size,
+			       prog->license, ctx->ifindex,
+			       ctx->log, ctx->log_size);
+	if (fd < 0 || ctx->verbose) {
+		/* The verifier log is pretty chatty, sometimes so chatty
+		 * on larger programs, that we could fail to dump everything
+		 * into our buffer. Still, try to give a debuggable error
+		 * log for the user, so enlarge it and re-fail.
+		 */
+		if (fd < 0 && errno == ENOSPC) {
+			if (tries++ < 10 && !bpf_log_realloc(ctx))
+				goto retry;
+
+			fprintf(stderr, "Log buffer too small to dump verifier log %zu bytes (%d tries)!\n",
+				ctx->log_size, tries);
+			return fd;
+		}
+
+		bpf_prog_report(fd, section, prog, ctx);
+	}
+
+	return fd;
+}
+
+static void bpf_map_report(int fd, const char *name,
+			   const struct bpf_elf_map *map,
+			   struct bpf_elf_ctx *ctx, int inner_fd)
+{
+	fprintf(stderr, "Map object \'%s\' %s%s (%d)!\n", name,
+		fd < 0 ? "rejected: " : "loaded",
+		fd < 0 ? strerror(errno) : "",
+		fd < 0 ? errno : fd);
+
+	fprintf(stderr, " - Type:         %u\n", map->type);
+	fprintf(stderr, " - Identifier:   %u\n", map->id);
+	fprintf(stderr, " - Pinning:      %u\n", map->pinning);
+	fprintf(stderr, " - Size key:     %u\n", map->size_key);
+	fprintf(stderr, " - Size value:   %u\n",
+		inner_fd ? (int)sizeof(int) : map->size_value);
+	fprintf(stderr, " - Max elems:    %u\n", map->max_elem);
+	fprintf(stderr, " - Flags:        %#x\n\n", map->flags);
+}
+
+static int bpf_find_map_id(const struct bpf_elf_ctx *ctx, uint32_t id)
+{
+	int i;
+
+	for (i = 0; i < ctx->map_num; i++) {
+		if (ctx->maps[i].id != id)
+			continue;
+		if (ctx->map_fds[i] < 0)
+			return -EINVAL;
+
+		return ctx->map_fds[i];
+	}
+
+	return -ENOENT;
+}
+
+static void bpf_report_map_in_map(int outer_fd, uint32_t idx)
+{
+	struct bpf_elf_map outer_map;
+	int ret;
+
+	fprintf(stderr, "Cannot insert map into map! ");
+
+	ret = bpf_derive_elf_map_from_fdinfo(outer_fd, &outer_map, NULL);
+	if (!ret) {
+		if (idx >= outer_map.max_elem &&
+		    outer_map.type == BPF_MAP_TYPE_ARRAY_OF_MAPS) {
+			fprintf(stderr, "Outer map has %u elements, index %u is invalid!\n",
+				outer_map.max_elem, idx);
+			return;
+		}
+	}
+
+	fprintf(stderr, "Different map specs used for outer and inner map?\n");
+}
+
+static bool bpf_is_map_in_map_type(const struct bpf_elf_map *map)
+{
+	return map->type == BPF_MAP_TYPE_ARRAY_OF_MAPS ||
+	       map->type == BPF_MAP_TYPE_HASH_OF_MAPS;
+}
+
+static bool bpf_map_offload_neutral(enum bpf_map_type type)
+{
+	return type == BPF_MAP_TYPE_PERF_EVENT_ARRAY;
+}
+
+static int bpf_map_attach(const char *name, struct bpf_elf_ctx *ctx,
+			  const struct bpf_elf_map *map, struct bpf_map_ext *ext,
+			  int *have_map_in_map)
+{
+	int fd, ifindex, ret, map_inner_fd = 0;
+	bool retried = false;
+
+probe:
+	fd = bpf_probe_pinned(name, ctx, map->pinning);
+	if (fd > 0) {
+		ret = bpf_map_selfcheck_pinned(fd, map, ext,
+					       offsetof(struct bpf_elf_map,
+							id), ctx->type);
+		if (ret < 0) {
+			close(fd);
+			fprintf(stderr, "Map \'%s\' self-check failed!\n",
+				name);
+			return ret;
+		}
+		if (ctx->verbose)
+			fprintf(stderr, "Map \'%s\' loaded as pinned!\n",
+				name);
+		return fd;
+	}
+
+	if (have_map_in_map && bpf_is_map_in_map_type(map)) {
+		(*have_map_in_map)++;
+		if (map->inner_id)
+			return 0;
+		fprintf(stderr, "Map \'%s\' cannot be created since no inner map ID defined!\n",
+			name);
+		return -EINVAL;
+	}
+
+	if (!have_map_in_map && bpf_is_map_in_map_type(map)) {
+		map_inner_fd = bpf_find_map_id(ctx, map->inner_id);
+		if (map_inner_fd < 0) {
+			fprintf(stderr, "Map \'%s\' cannot be loaded. Inner map with ID %u not found!\n",
+				name, map->inner_id);
+			return -EINVAL;
+		}
+	}
+
+	ifindex = bpf_map_offload_neutral(map->type) ? 0 : ctx->ifindex;
+	errno = 0;
+	fd = bpf_map_create(map->type, map->size_key, map->size_value,
+			    map->max_elem, map->flags, map_inner_fd, ctx->btf_fd,
+			    ifindex, ext->btf_id_key, ext->btf_id_val);
+
+	if (fd < 0 || ctx->verbose) {
+		bpf_map_report(fd, name, map, ctx, map_inner_fd);
+		if (fd < 0)
+			return fd;
+	}
+
+	ret = bpf_place_pinned(fd, name, ctx, map->pinning);
+	if (ret < 0) {
+		close(fd);
+		if (!retried && errno == EEXIST) {
+			retried = true;
+			goto probe;
+		}
+		fprintf(stderr, "Could not pin %s map: %s\n", name,
+			strerror(errno));
+		return ret;
+	}
+
+	return fd;
+}
+
+static const char *bpf_str_tab_name(const struct bpf_elf_ctx *ctx,
+				    const GElf_Sym *sym)
+{
+	return ctx->str_tab->d_buf + sym->st_name;
+}
+
+static int bpf_btf_find(struct bpf_elf_ctx *ctx, const char *name)
+{
+	const struct btf_type *type;
+	const char *res;
+	int id;
+
+	for (id = 1; id < ctx->btf.types_num; id++) {
+		type = ctx->btf.types[id];
+		if (type->name_off >= ctx->btf.hdr->str_len)
+			continue;
+		res = &ctx->btf.strings[type->name_off];
+		if (!strcmp(res, name))
+			return id;
+	}
+
+	return -ENOENT;
+}
+
+static int bpf_btf_find_kv(struct bpf_elf_ctx *ctx, const struct bpf_elf_map *map,
+			   const char *name, uint32_t *id_key, uint32_t *id_val)
+{
+	const struct btf_member *key, *val;
+	const struct btf_type *type;
+	char btf_name[512];
+	const char *res;
+	int id;
+
+	snprintf(btf_name, sizeof(btf_name), "____btf_map_%s", name);
+	id = bpf_btf_find(ctx, btf_name);
+	if (id < 0)
+		return id;
+
+	type = ctx->btf.types[id];
+	if (BTF_INFO_KIND(type->info) != BTF_KIND_STRUCT)
+		return -EINVAL;
+	if (BTF_INFO_VLEN(type->info) != 2)
+		return -EINVAL;
+
+	key = ((void *) type) + sizeof(*type);
+	val = key + 1;
+	if (!key->type || key->type >= ctx->btf.types_num ||
+	    !val->type || val->type >= ctx->btf.types_num)
+		return -EINVAL;
+
+	if (key->name_off >= ctx->btf.hdr->str_len ||
+	    val->name_off >= ctx->btf.hdr->str_len)
+		return -EINVAL;
+
+	res = &ctx->btf.strings[key->name_off];
+	if (strcmp(res, "key"))
+		return -EINVAL;
+
+	res = &ctx->btf.strings[val->name_off];
+	if (strcmp(res, "value"))
+		return -EINVAL;
+
+	*id_key = key->type;
+	*id_val = val->type;
+	return 0;
+}
+
+static void bpf_btf_annotate(struct bpf_elf_ctx *ctx, int which, const char *name)
+{
+	uint32_t id_key = 0, id_val = 0;
+
+	if (!bpf_btf_find_kv(ctx, &ctx->maps[which], name, &id_key, &id_val)) {
+		ctx->maps_ext[which].btf_id_key = id_key;
+		ctx->maps_ext[which].btf_id_val = id_val;
+	}
+}
+
+static const char *bpf_map_fetch_name(struct bpf_elf_ctx *ctx, int which)
+{
+	const char *name;
+	GElf_Sym sym;
+	int i;
+
+	for (i = 0; i < ctx->sym_num; i++) {
+		int type;
+
+		if (gelf_getsym(ctx->sym_tab, i, &sym) != &sym)
+			continue;
+
+		type = GELF_ST_TYPE(sym.st_info);
+		if (GELF_ST_BIND(sym.st_info) != STB_GLOBAL ||
+		    (type != STT_NOTYPE && type != STT_OBJECT) ||
+		    sym.st_shndx != ctx->sec_maps ||
+		    sym.st_value / ctx->map_len != which)
+			continue;
+
+		name = bpf_str_tab_name(ctx, &sym);
+		bpf_btf_annotate(ctx, which, name);
+		return name;
+	}
+
+	return NULL;
+}
+
+static int bpf_maps_attach_all(struct bpf_elf_ctx *ctx)
+{
+	int i, j, ret, fd, inner_fd, inner_idx, have_map_in_map = 0;
+	const char *map_name;
+
+	for (i = 0; i < ctx->map_num; i++) {
+		if (ctx->maps[i].pinning == PIN_OBJECT_NS &&
+		    ctx->noafalg) {
+			fprintf(stderr, "Missing kernel AF_ALG support for PIN_OBJECT_NS!\n");
+			return -ENOTSUP;
+		}
+
+		map_name = bpf_map_fetch_name(ctx, i);
+		if (!map_name)
+			return -EIO;
+
+		fd = bpf_map_attach(map_name, ctx, &ctx->maps[i],
+				    &ctx->maps_ext[i], &have_map_in_map);
+		if (fd < 0)
+			return fd;
+
+		ctx->map_fds[i] = !fd ? -1 : fd;
+	}
+
+	for (i = 0; have_map_in_map && i < ctx->map_num; i++) {
+		if (ctx->map_fds[i] >= 0)
+			continue;
+
+		map_name = bpf_map_fetch_name(ctx, i);
+		if (!map_name)
+			return -EIO;
+
+		fd = bpf_map_attach(map_name, ctx, &ctx->maps[i],
+				    &ctx->maps_ext[i], NULL);
+		if (fd < 0)
+			return fd;
+
+		ctx->map_fds[i] = fd;
+	}
+
+	for (i = 0; have_map_in_map && i < ctx->map_num; i++) {
+		if (!ctx->maps[i].id ||
+		    ctx->maps[i].inner_id ||
+		    ctx->maps[i].inner_idx == -1)
+			continue;
+
+		inner_fd  = ctx->map_fds[i];
+		inner_idx = ctx->maps[i].inner_idx;
+
+		for (j = 0; j < ctx->map_num; j++) {
+			if (!bpf_is_map_in_map_type(&ctx->maps[j]))
+				continue;
+			if (ctx->maps[j].inner_id != ctx->maps[i].id)
+				continue;
+
+			ret = bpf_map_update(ctx->map_fds[j], &inner_idx,
+					     &inner_fd, BPF_ANY);
+			if (ret < 0) {
+				bpf_report_map_in_map(ctx->map_fds[j],
+						      inner_idx);
+				return ret;
+			}
+		}
+	}
+
+	return 0;
+}
+
+static int bpf_map_num_sym(struct bpf_elf_ctx *ctx)
+{
+	int i, num = 0;
+	GElf_Sym sym;
+
+	for (i = 0; i < ctx->sym_num; i++) {
+		int type;
+
+		if (gelf_getsym(ctx->sym_tab, i, &sym) != &sym)
+			continue;
+
+		type = GELF_ST_TYPE(sym.st_info);
+		if (GELF_ST_BIND(sym.st_info) != STB_GLOBAL ||
+		    (type != STT_NOTYPE && type != STT_OBJECT) ||
+		    sym.st_shndx != ctx->sec_maps)
+			continue;
+		num++;
+	}
+
+	return num;
+}
+
+static int bpf_fill_section_data(struct bpf_elf_ctx *ctx, int section,
+				 struct bpf_elf_sec_data *data)
+{
+	Elf_Data *sec_edata;
+	GElf_Shdr sec_hdr;
+	Elf_Scn *sec_fd;
+	char *sec_name;
+
+	memset(data, 0, sizeof(*data));
+
+	sec_fd = elf_getscn(ctx->elf_fd, section);
+	if (!sec_fd)
+		return -EINVAL;
+	if (gelf_getshdr(sec_fd, &sec_hdr) != &sec_hdr)
+		return -EIO;
+
+	sec_name = elf_strptr(ctx->elf_fd, ctx->elf_hdr.e_shstrndx,
+			      sec_hdr.sh_name);
+	if (!sec_name || !sec_hdr.sh_size)
+		return -ENOENT;
+
+	sec_edata = elf_getdata(sec_fd, NULL);
+	if (!sec_edata || elf_getdata(sec_fd, sec_edata))
+		return -EIO;
+
+	memcpy(&data->sec_hdr, &sec_hdr, sizeof(sec_hdr));
+
+	data->sec_name = sec_name;
+	data->sec_data = sec_edata;
+	return 0;
+}
+
+struct bpf_elf_map_min {
+	__u32 type;
+	__u32 size_key;
+	__u32 size_value;
+	__u32 max_elem;
+};
+
+static int bpf_fetch_maps_begin(struct bpf_elf_ctx *ctx, int section,
+				struct bpf_elf_sec_data *data)
+{
+	ctx->map_num = data->sec_data->d_size;
+	ctx->sec_maps = section;
+	ctx->sec_done[section] = true;
+
+	if (ctx->map_num > sizeof(ctx->maps)) {
+		fprintf(stderr, "Too many BPF maps in ELF section!\n");
+		return -ENOMEM;
+	}
+
+	memcpy(ctx->maps, data->sec_data->d_buf, ctx->map_num);
+	return 0;
+}
+
+static int bpf_map_verify_all_offs(struct bpf_elf_ctx *ctx, int end)
+{
+	GElf_Sym sym;
+	int off, i;
+
+	for (off = 0; off < end; off += ctx->map_len) {
+		/* Order doesn't need to be linear here, hence we walk
+		 * the table again.
+		 */
+		for (i = 0; i < ctx->sym_num; i++) {
+			int type;
+
+			if (gelf_getsym(ctx->sym_tab, i, &sym) != &sym)
+				continue;
+
+			type = GELF_ST_TYPE(sym.st_info);
+			if (GELF_ST_BIND(sym.st_info) != STB_GLOBAL ||
+			    (type != STT_NOTYPE && type != STT_OBJECT) ||
+			    sym.st_shndx != ctx->sec_maps)
+				continue;
+			if (sym.st_value == off)
+				break;
+			if (i == ctx->sym_num - 1)
+				return -1;
+		}
+	}
+
+	return off == end ? 0 : -1;
+}
+
+static int bpf_fetch_maps_end(struct bpf_elf_ctx *ctx)
+{
+	struct bpf_elf_map fixup[ARRAY_SIZE(ctx->maps)] = {};
+	int i, sym_num = bpf_map_num_sym(ctx);
+	__u8 *buff;
+
+	if (sym_num == 0 || sym_num > ARRAY_SIZE(ctx->maps)) {
+		fprintf(stderr, "%u maps not supported in current map section!\n",
+			sym_num);
+		return -EINVAL;
+	}
+
+	if (ctx->map_num % sym_num != 0 ||
+	    ctx->map_num % sizeof(__u32) != 0) {
+		fprintf(stderr, "Number BPF map symbols are not multiple of struct bpf_elf_map!\n");
+		return -EINVAL;
+	}
+
+	ctx->map_len = ctx->map_num / sym_num;
+	if (bpf_map_verify_all_offs(ctx, ctx->map_num)) {
+		fprintf(stderr, "Different struct bpf_elf_map in use!\n");
+		return -EINVAL;
+	}
+
+	if (ctx->map_len == sizeof(struct bpf_elf_map)) {
+		ctx->map_num = sym_num;
+		return 0;
+	} else if (ctx->map_len > sizeof(struct bpf_elf_map)) {
+		fprintf(stderr, "struct bpf_elf_map not supported, coming from future version?\n");
+		return -EINVAL;
+	} else if (ctx->map_len < sizeof(struct bpf_elf_map_min)) {
+		fprintf(stderr, "struct bpf_elf_map too small, not supported!\n");
+		return -EINVAL;
+	}
+
+	ctx->map_num = sym_num;
+	for (i = 0, buff = (void *)ctx->maps; i < ctx->map_num;
+	     i++, buff += ctx->map_len) {
+		/* The fixup leaves the rest of the members as zero, which
+		 * is fine currently, but option exist to set some other
+		 * default value as well when needed in future.
+		 */
+		memcpy(&fixup[i], buff, ctx->map_len);
+	}
+
+	memcpy(ctx->maps, fixup, sizeof(fixup));
+	if (ctx->verbose)
+		printf("%zu bytes struct bpf_elf_map fixup performed due to size mismatch!\n",
+		       sizeof(struct bpf_elf_map) - ctx->map_len);
+	return 0;
+}
+
+static int bpf_fetch_license(struct bpf_elf_ctx *ctx, int section,
+			     struct bpf_elf_sec_data *data)
+{
+	if (data->sec_data->d_size > sizeof(ctx->license))
+		return -ENOMEM;
+
+	memcpy(ctx->license, data->sec_data->d_buf, data->sec_data->d_size);
+	ctx->sec_done[section] = true;
+	return 0;
+}
+
+static int bpf_fetch_symtab(struct bpf_elf_ctx *ctx, int section,
+			    struct bpf_elf_sec_data *data)
+{
+	ctx->sym_tab = data->sec_data;
+	ctx->sym_num = data->sec_hdr.sh_size / data->sec_hdr.sh_entsize;
+	ctx->sec_done[section] = true;
+	return 0;
+}
+
+static int bpf_fetch_strtab(struct bpf_elf_ctx *ctx, int section,
+			    struct bpf_elf_sec_data *data)
+{
+	ctx->str_tab = data->sec_data;
+	ctx->sec_done[section] = true;
+	return 0;
+}
+
+static int bpf_fetch_text(struct bpf_elf_ctx *ctx, int section,
+			  struct bpf_elf_sec_data *data)
+{
+	ctx->sec_text = section;
+	ctx->sec_done[section] = true;
+	return 0;
+}
+
+static void bpf_btf_report(int fd, struct bpf_elf_ctx *ctx)
+{
+	fprintf(stderr, "\nBTF debug data section \'.BTF\' %s%s (%d)!\n",
+		fd < 0 ? "rejected: " : "loaded",
+		fd < 0 ? strerror(errno) : "",
+		fd < 0 ? errno : fd);
+
+	fprintf(stderr, " - Length:       %zu\n", ctx->btf_data->d_size);
+
+	bpf_dump_error(ctx, "Verifier analysis:\n\n");
+}
+
+static int bpf_btf_attach(struct bpf_elf_ctx *ctx)
+{
+	int tries = 0, fd;
+retry:
+	errno = 0;
+	fd = bpf_btf_load(ctx->btf_data->d_buf, ctx->btf_data->d_size,
+			  ctx->log, ctx->log_size);
+	if (fd < 0 || ctx->verbose) {
+		if (fd < 0 && errno == ENOSPC) {
+			if (tries++ < 10 && !bpf_log_realloc(ctx))
+				goto retry;
+
+			fprintf(stderr, "Log buffer too small to dump verifier log %zu bytes (%d tries)!\n",
+				ctx->log_size, tries);
+			return fd;
+		}
+
+		if (bpf_log_has_data(ctx))
+			bpf_btf_report(fd, ctx);
+	}
+
+	return fd;
+}
+
+static int bpf_fetch_btf_begin(struct bpf_elf_ctx *ctx, int section,
+			       struct bpf_elf_sec_data *data)
+{
+	ctx->btf_data = data->sec_data;
+	ctx->sec_btf = section;
+	ctx->sec_done[section] = true;
+	return 0;
+}
+
+static int bpf_btf_check_header(struct bpf_elf_ctx *ctx)
+{
+	const struct btf_header *hdr = ctx->btf_data->d_buf;
+	const char *str_start, *str_end;
+	unsigned int data_len;
+
+	if (hdr->magic != BTF_MAGIC) {
+		fprintf(stderr, "Object has wrong BTF magic: %x, expected: %x!\n",
+			hdr->magic, BTF_MAGIC);
+		return -EINVAL;
+	}
+
+	if (hdr->version != BTF_VERSION) {
+		fprintf(stderr, "Object has wrong BTF version: %u, expected: %u!\n",
+			hdr->version, BTF_VERSION);
+		return -EINVAL;
+	}
+
+	if (hdr->flags) {
+		fprintf(stderr, "Object has unsupported BTF flags %x!\n",
+			hdr->flags);
+		return -EINVAL;
+	}
+
+	data_len = ctx->btf_data->d_size - sizeof(*hdr);
+	if (data_len < hdr->type_off ||
+	    data_len < hdr->str_off ||
+	    data_len < hdr->type_len + hdr->str_len ||
+	    hdr->type_off >= hdr->str_off ||
+	    hdr->type_off + hdr->type_len != hdr->str_off ||
+	    hdr->str_off + hdr->str_len != data_len ||
+	    (hdr->type_off & (sizeof(uint32_t) - 1))) {
+		fprintf(stderr, "Object has malformed BTF data!\n");
+		return -EINVAL;
+	}
+
+	ctx->btf.hdr = hdr;
+	ctx->btf.raw = hdr + 1;
+
+	str_start = ctx->btf.raw + hdr->str_off;
+	str_end = str_start + hdr->str_len;
+	if (!hdr->str_len ||
+	    hdr->str_len - 1 > BTF_MAX_NAME_OFFSET ||
+	    str_start[0] || str_end[-1]) {
+		fprintf(stderr, "Object has malformed BTF string data!\n");
+		return -EINVAL;
+	}
+
+	ctx->btf.strings = str_start;
+	return 0;
+}
+
+static int bpf_btf_register_type(struct bpf_elf_ctx *ctx,
+				 const struct btf_type *type)
+{
+	int cur = ctx->btf.types_num, num = cur + 1;
+	const struct btf_type **types;
+
+	types = realloc(ctx->btf.types, num * sizeof(type));
+	if (!types) {
+		free(ctx->btf.types);
+		ctx->btf.types = NULL;
+		ctx->btf.types_num = 0;
+		return -ENOMEM;
+	}
+
+	ctx->btf.types = types;
+	ctx->btf.types[cur] = type;
+	ctx->btf.types_num = num;
+	return 0;
+}
+
+static struct btf_type btf_type_void;
+
+static int bpf_btf_prep_type_data(struct bpf_elf_ctx *ctx)
+{
+	const void *type_cur = ctx->btf.raw + ctx->btf.hdr->type_off;
+	const void *type_end = ctx->btf.raw + ctx->btf.hdr->str_off;
+	const struct btf_type *type;
+	uint16_t var_len;
+	int ret, kind;
+
+	ret = bpf_btf_register_type(ctx, &btf_type_void);
+	if (ret < 0)
+		return ret;
+
+	while (type_cur < type_end) {
+		type = type_cur;
+		type_cur += sizeof(*type);
+
+		var_len = BTF_INFO_VLEN(type->info);
+		kind = BTF_INFO_KIND(type->info);
+
+		switch (kind) {
+		case BTF_KIND_INT:
+			type_cur += sizeof(int);
+			break;
+		case BTF_KIND_ARRAY:
+			type_cur += sizeof(struct btf_array);
+			break;
+		case BTF_KIND_STRUCT:
+		case BTF_KIND_UNION:
+			type_cur += var_len * sizeof(struct btf_member);
+			break;
+		case BTF_KIND_ENUM:
+			type_cur += var_len * sizeof(struct btf_enum);
+			break;
+		case BTF_KIND_FUNC_PROTO:
+			type_cur += var_len * sizeof(struct btf_param);
+			break;
+		case BTF_KIND_TYPEDEF:
+		case BTF_KIND_PTR:
+		case BTF_KIND_FWD:
+		case BTF_KIND_VOLATILE:
+		case BTF_KIND_CONST:
+		case BTF_KIND_RESTRICT:
+		case BTF_KIND_FUNC:
+			break;
+		default:
+			fprintf(stderr, "Object has unknown BTF type: %u!\n", kind);
+			return -EINVAL;
+		}
+
+		ret = bpf_btf_register_type(ctx, type);
+		if (ret < 0)
+			return ret;
+	}
+
+	return 0;
+}
+
+static int bpf_btf_prep_data(struct bpf_elf_ctx *ctx)
+{
+	int ret = bpf_btf_check_header(ctx);
+
+	if (!ret)
+		return bpf_btf_prep_type_data(ctx);
+	return ret;
+}
+
+static void bpf_fetch_btf_end(struct bpf_elf_ctx *ctx)
+{
+	int fd = bpf_btf_attach(ctx);
+
+	if (fd < 0)
+		return;
+	ctx->btf_fd = fd;
+	if (bpf_btf_prep_data(ctx) < 0) {
+		close(ctx->btf_fd);
+		ctx->btf_fd = 0;
+	}
+}
+
+static bool bpf_has_map_data(const struct bpf_elf_ctx *ctx)
+{
+	return ctx->sym_tab && ctx->str_tab && ctx->sec_maps;
+}
+
+static bool bpf_has_btf_data(const struct bpf_elf_ctx *ctx)
+{
+	return ctx->sec_btf;
+}
+
+static bool bpf_has_call_data(const struct bpf_elf_ctx *ctx)
+{
+	return ctx->sec_text;
+}
+
+static int bpf_fetch_ancillary(struct bpf_elf_ctx *ctx, bool check_text_sec)
+{
+	struct bpf_elf_sec_data data;
+	int i, ret = -1;
+
+	for (i = 1; i < ctx->elf_hdr.e_shnum; i++) {
+		ret = bpf_fill_section_data(ctx, i, &data);
+		if (ret < 0)
+			continue;
+
+		if (data.sec_hdr.sh_type == SHT_PROGBITS &&
+		    !strcmp(data.sec_name, ELF_SECTION_MAPS))
+			ret = bpf_fetch_maps_begin(ctx, i, &data);
+		else if (data.sec_hdr.sh_type == SHT_PROGBITS &&
+			 !strcmp(data.sec_name, ELF_SECTION_LICENSE))
+			ret = bpf_fetch_license(ctx, i, &data);
+		else if (data.sec_hdr.sh_type == SHT_PROGBITS &&
+			 (data.sec_hdr.sh_flags & SHF_EXECINSTR) &&
+			 !strcmp(data.sec_name, ".text") &&
+			 check_text_sec)
+			ret = bpf_fetch_text(ctx, i, &data);
+		else if (data.sec_hdr.sh_type == SHT_SYMTAB &&
+			 !strcmp(data.sec_name, ".symtab"))
+			ret = bpf_fetch_symtab(ctx, i, &data);
+		else if (data.sec_hdr.sh_type == SHT_STRTAB &&
+			 !strcmp(data.sec_name, ".strtab"))
+			ret = bpf_fetch_strtab(ctx, i, &data);
+		else if (data.sec_hdr.sh_type == SHT_PROGBITS &&
+			 !strcmp(data.sec_name, ".BTF"))
+			ret = bpf_fetch_btf_begin(ctx, i, &data);
+		if (ret < 0) {
+			fprintf(stderr, "Error parsing section %d! Perhaps check with readelf -a?\n",
+				i);
+			return ret;
+		}
+	}
+
+	if (bpf_has_btf_data(ctx))
+		bpf_fetch_btf_end(ctx);
+	if (bpf_has_map_data(ctx)) {
+		ret = bpf_fetch_maps_end(ctx);
+		if (ret < 0) {
+			fprintf(stderr, "Error fixing up map structure, incompatible struct bpf_elf_map used?\n");
+			return ret;
+		}
+
+		ret = bpf_maps_attach_all(ctx);
+		if (ret < 0) {
+			fprintf(stderr, "Error loading maps into kernel!\n");
+			return ret;
+		}
+	}
+
+	return ret;
+}
+
+static int bpf_fetch_prog(struct bpf_elf_ctx *ctx, const char *section,
+			  bool *sseen)
+{
+	struct bpf_elf_sec_data data;
+	struct bpf_elf_prog prog;
+	int ret, i, fd = -1;
+
+	for (i = 1; i < ctx->elf_hdr.e_shnum; i++) {
+		if (ctx->sec_done[i])
+			continue;
+
+		ret = bpf_fill_section_data(ctx, i, &data);
+		if (ret < 0 ||
+		    !(data.sec_hdr.sh_type == SHT_PROGBITS &&
+		      (data.sec_hdr.sh_flags & SHF_EXECINSTR) &&
+		      !strcmp(data.sec_name, section)))
+			continue;
+
+		*sseen = true;
+
+		memset(&prog, 0, sizeof(prog));
+		prog.type      = ctx->type;
+		prog.license   = ctx->license;
+		prog.size      = data.sec_data->d_size;
+		prog.insns_num = prog.size / sizeof(struct bpf_insn);
+		prog.insns     = data.sec_data->d_buf;
+
+		fd = bpf_prog_attach(section, &prog, ctx);
+		if (fd < 0)
+			return fd;
+
+		ctx->sec_done[i] = true;
+		break;
+	}
+
+	return fd;
+}
+
+struct bpf_relo_props {
+	struct bpf_tail_call {
+		unsigned int total;
+		unsigned int jited;
+	} tc;
+	int main_num;
+};
+
+static int bpf_apply_relo_map(struct bpf_elf_ctx *ctx, struct bpf_elf_prog *prog,
+			      GElf_Rel *relo, GElf_Sym *sym,
+			      struct bpf_relo_props *props)
+{
+	unsigned int insn_off = relo->r_offset / sizeof(struct bpf_insn);
+	unsigned int map_idx = sym->st_value / ctx->map_len;
+
+	if (insn_off >= prog->insns_num)
+		return -EINVAL;
+	if (prog->insns[insn_off].code != (BPF_LD | BPF_IMM | BPF_DW)) {
+		fprintf(stderr, "ELF contains relo data for non ld64 instruction at offset %u! Compiler bug?!\n",
+			insn_off);
+		return -EINVAL;
+	}
+
+	if (map_idx >= ARRAY_SIZE(ctx->map_fds))
+		return -EINVAL;
+	if (!ctx->map_fds[map_idx])
+		return -EINVAL;
+	if (ctx->maps[map_idx].type == BPF_MAP_TYPE_PROG_ARRAY) {
+		props->tc.total++;
+		if (ctx->maps_ext[map_idx].owner.jited ||
+		    (ctx->maps_ext[map_idx].owner.type == 0 &&
+		     ctx->cfg.jit_enabled))
+			props->tc.jited++;
+	}
+
+	prog->insns[insn_off].src_reg = BPF_PSEUDO_MAP_FD;
+	prog->insns[insn_off].imm = ctx->map_fds[map_idx];
+	return 0;
+}
+
+static int bpf_apply_relo_call(struct bpf_elf_ctx *ctx, struct bpf_elf_prog *prog,
+			       GElf_Rel *relo, GElf_Sym *sym,
+			       struct bpf_relo_props *props)
+{
+	unsigned int insn_off = relo->r_offset / sizeof(struct bpf_insn);
+	struct bpf_elf_prog *prog_text = &ctx->prog_text;
+
+	if (insn_off >= prog->insns_num)
+		return -EINVAL;
+	if (prog->insns[insn_off].code != (BPF_JMP | BPF_CALL) &&
+	    prog->insns[insn_off].src_reg != BPF_PSEUDO_CALL) {
+		fprintf(stderr, "ELF contains relo data for non call instruction at offset %u! Compiler bug?!\n",
+			insn_off);
+		return -EINVAL;
+	}
+
+	if (!props->main_num) {
+		struct bpf_insn *insns = realloc(prog->insns,
+						 prog->size + prog_text->size);
+		if (!insns)
+			return -ENOMEM;
+
+		memcpy(insns + prog->insns_num, prog_text->insns,
+		       prog_text->size);
+		props->main_num = prog->insns_num;
+		prog->insns = insns;
+		prog->insns_num += prog_text->insns_num;
+		prog->size += prog_text->size;
+	}
+
+	prog->insns[insn_off].imm += props->main_num - insn_off;
+	return 0;
+}
+
+static int bpf_apply_relo_data(struct bpf_elf_ctx *ctx,
+			       struct bpf_elf_sec_data *data_relo,
+			       struct bpf_elf_prog *prog,
+			       struct bpf_relo_props *props)
+{
+	GElf_Shdr *rhdr = &data_relo->sec_hdr;
+	int relo_ent, relo_num = rhdr->sh_size / rhdr->sh_entsize;
+
+	for (relo_ent = 0; relo_ent < relo_num; relo_ent++) {
+		GElf_Rel relo;
+		GElf_Sym sym;
+		int ret = -EIO;
+
+		if (gelf_getrel(data_relo->sec_data, relo_ent, &relo) != &relo)
+			return -EIO;
+		if (gelf_getsym(ctx->sym_tab, GELF_R_SYM(relo.r_info), &sym) != &sym)
+			return -EIO;
+
+		if (sym.st_shndx == ctx->sec_maps)
+			ret = bpf_apply_relo_map(ctx, prog, &relo, &sym, props);
+		else if (sym.st_shndx == ctx->sec_text)
+			ret = bpf_apply_relo_call(ctx, prog, &relo, &sym, props);
+		else
+			fprintf(stderr, "ELF contains non-{map,call} related relo data in entry %u pointing to section %u! Compiler bug?!\n",
+				relo_ent, sym.st_shndx);
+		if (ret < 0)
+			return ret;
+	}
+
+	return 0;
+}
+
+static int bpf_fetch_prog_relo(struct bpf_elf_ctx *ctx, const char *section,
+			       bool *lderr, bool *sseen, struct bpf_elf_prog *prog)
+{
+	struct bpf_elf_sec_data data_relo, data_insn;
+	int ret, idx, i, fd = -1;
+
+	for (i = 1; i < ctx->elf_hdr.e_shnum; i++) {
+		struct bpf_relo_props props = {};
+
+		ret = bpf_fill_section_data(ctx, i, &data_relo);
+		if (ret < 0 || data_relo.sec_hdr.sh_type != SHT_REL)
+			continue;
+
+		idx = data_relo.sec_hdr.sh_info;
+
+		ret = bpf_fill_section_data(ctx, idx, &data_insn);
+		if (ret < 0 ||
+		    !(data_insn.sec_hdr.sh_type == SHT_PROGBITS &&
+		      (data_insn.sec_hdr.sh_flags & SHF_EXECINSTR) &&
+		      !strcmp(data_insn.sec_name, section)))
+			continue;
+		if (sseen)
+			*sseen = true;
+
+		memset(prog, 0, sizeof(*prog));
+		prog->type = ctx->type;
+		prog->license = ctx->license;
+		prog->size = data_insn.sec_data->d_size;
+		prog->insns_num = prog->size / sizeof(struct bpf_insn);
+		prog->insns = malloc(prog->size);
+		if (!prog->insns) {
+			*lderr = true;
+			return -ENOMEM;
+		}
+
+		memcpy(prog->insns, data_insn.sec_data->d_buf, prog->size);
+
+		ret = bpf_apply_relo_data(ctx, &data_relo, prog, &props);
+		if (ret < 0) {
+			*lderr = true;
+			if (ctx->sec_text != idx)
+				free(prog->insns);
+			return ret;
+		}
+		if (ctx->sec_text == idx) {
+			fd = 0;
+			goto out;
+		}
+
+		fd = bpf_prog_attach(section, prog, ctx);
+		free(prog->insns);
+		if (fd < 0) {
+			*lderr = true;
+			if (props.tc.total) {
+				if (ctx->cfg.jit_enabled &&
+				    props.tc.total != props.tc.jited)
+					fprintf(stderr, "JIT enabled, but only %u/%u tail call maps in the program have JITed owner!\n",
+						props.tc.jited, props.tc.total);
+				if (!ctx->cfg.jit_enabled &&
+				    props.tc.jited)
+					fprintf(stderr, "JIT disabled, but %u/%u tail call maps in the program have JITed owner!\n",
+						props.tc.jited, props.tc.total);
+			}
+			return fd;
+		}
+out:
+		ctx->sec_done[i]   = true;
+		ctx->sec_done[idx] = true;
+		break;
+	}
+
+	return fd;
+}
+
+static int bpf_fetch_prog_sec(struct bpf_elf_ctx *ctx, const char *section)
+{
+	bool lderr = false, sseen = false;
+	struct bpf_elf_prog prog;
+	int ret = -1;
+
+	if (bpf_has_call_data(ctx)) {
+		ret = bpf_fetch_prog_relo(ctx, ".text", &lderr, NULL,
+					  &ctx->prog_text);
+		if (ret < 0)
+			return ret;
+	}
+
+	if (bpf_has_map_data(ctx) || bpf_has_call_data(ctx))
+		ret = bpf_fetch_prog_relo(ctx, section, &lderr, &sseen, &prog);
+	if (ret < 0 && !lderr)
+		ret = bpf_fetch_prog(ctx, section, &sseen);
+	if (ret < 0 && !sseen)
+		fprintf(stderr, "Program section \'%s\' not found in ELF file!\n",
+			section);
+	return ret;
+}
+
+static int bpf_find_map_by_id(struct bpf_elf_ctx *ctx, uint32_t id)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(ctx->map_fds); i++)
+		if (ctx->map_fds[i] && ctx->maps[i].id == id &&
+		    ctx->maps[i].type == BPF_MAP_TYPE_PROG_ARRAY)
+			return i;
+	return -1;
+}
+
+struct bpf_jited_aux {
+	int prog_fd;
+	int map_fd;
+	struct bpf_prog_data prog;
+	struct bpf_map_ext map;
+};
+
+static int bpf_derive_prog_from_fdinfo(int fd, struct bpf_prog_data *prog)
+{
+	char file[PATH_MAX], buff[4096];
+	unsigned int val;
+	FILE *fp;
+
+	snprintf(file, sizeof(file), "/proc/%d/fdinfo/%d", getpid(), fd);
+	memset(prog, 0, sizeof(*prog));
+
+	fp = fopen(file, "r");
+	if (!fp) {
+		fprintf(stderr, "No procfs support?!\n");
+		return -EIO;
+	}
+
+	while (fgets(buff, sizeof(buff), fp)) {
+		if (sscanf(buff, "prog_type:\t%u", &val) == 1)
+			prog->type = val;
+		else if (sscanf(buff, "prog_jited:\t%u", &val) == 1)
+			prog->jited = val;
+	}
+
+	fclose(fp);
+	return 0;
+}
+
+static int bpf_tail_call_get_aux(struct bpf_jited_aux *aux)
+{
+	struct bpf_elf_map tmp;
+	int ret;
+
+	ret = bpf_derive_elf_map_from_fdinfo(aux->map_fd, &tmp, &aux->map);
+	if (!ret)
+		ret = bpf_derive_prog_from_fdinfo(aux->prog_fd, &aux->prog);
+
+	return ret;
+}
+
+static int bpf_fill_prog_arrays(struct bpf_elf_ctx *ctx)
+{
+	struct bpf_elf_sec_data data;
+	uint32_t map_id, key_id;
+	int fd, i, ret, idx;
+
+	for (i = 1; i < ctx->elf_hdr.e_shnum; i++) {
+		if (ctx->sec_done[i])
+			continue;
+
+		ret = bpf_fill_section_data(ctx, i, &data);
+		if (ret < 0)
+			continue;
+
+		ret = sscanf(data.sec_name, "%i/%i", &map_id, &key_id);
+		if (ret != 2)
+			continue;
+
+		idx = bpf_find_map_by_id(ctx, map_id);
+		if (idx < 0)
+			continue;
+
+		fd = bpf_fetch_prog_sec(ctx, data.sec_name);
+		if (fd < 0)
+			return -EIO;
+
+		ret = bpf_map_update(ctx->map_fds[idx], &key_id,
+				     &fd, BPF_ANY);
+		if (ret < 0) {
+			struct bpf_jited_aux aux = {};
+
+			ret = -errno;
+			if (errno == E2BIG) {
+				fprintf(stderr, "Tail call key %u for map %u out of bounds?\n",
+					key_id, map_id);
+				return ret;
+			}
+
+			aux.map_fd  = ctx->map_fds[idx];
+			aux.prog_fd = fd;
+
+			if (bpf_tail_call_get_aux(&aux))
+				return ret;
+			if (!aux.map.owner.type)
+				return ret;
+
+			if (aux.prog.type != aux.map.owner.type)
+				fprintf(stderr, "Tail call map owned by prog type %u, but prog type is %u!\n",
+					aux.map.owner.type, aux.prog.type);
+			if (aux.prog.jited != aux.map.owner.jited)
+				fprintf(stderr, "Tail call map %s jited, but prog %s!\n",
+					aux.map.owner.jited ? "is" : "not",
+					aux.prog.jited ? "is" : "not");
+			return ret;
+		}
+
+		ctx->sec_done[i] = true;
+	}
+
+	return 0;
+}
+
+static void bpf_save_finfo(struct bpf_elf_ctx *ctx)
+{
+	struct stat st;
+	int ret;
+
+	memset(&ctx->stat, 0, sizeof(ctx->stat));
+
+	ret = fstat(ctx->obj_fd, &st);
+	if (ret < 0) {
+		fprintf(stderr, "Stat of elf file failed: %s\n",
+			strerror(errno));
+		return;
+	}
+
+	ctx->stat.st_dev = st.st_dev;
+	ctx->stat.st_ino = st.st_ino;
+}
+
+static int bpf_read_pin_mapping(FILE *fp, uint32_t *id, char *path)
+{
+	char buff[PATH_MAX];
+
+	while (fgets(buff, sizeof(buff), fp)) {
+		char *ptr = buff;
+
+		while (*ptr == ' ' || *ptr == '\t')
+			ptr++;
+
+		if (*ptr == '#' || *ptr == '\n' || *ptr == 0)
+			continue;
+
+		if (sscanf(ptr, "%i %s\n", id, path) != 2 &&
+		    sscanf(ptr, "%i %s #", id, path) != 2) {
+			strcpy(path, ptr);
+			return -1;
+		}
+
+		return 1;
+	}
+
+	return 0;
+}
+
+static bool bpf_pinning_reserved(uint32_t pinning)
+{
+	switch (pinning) {
+	case PIN_NONE:
+	case PIN_OBJECT_NS:
+	case PIN_GLOBAL_NS:
+		return true;
+	default:
+		return false;
+	}
+}
+
+static void bpf_hash_init(struct bpf_elf_ctx *ctx, const char *db_file)
+{
+	struct bpf_hash_entry *entry;
+	char subpath[PATH_MAX] = {};
+	uint32_t pinning;
+	FILE *fp;
+	int ret;
+
+	fp = fopen(db_file, "r");
+	if (!fp)
+		return;
+
+	while ((ret = bpf_read_pin_mapping(fp, &pinning, subpath))) {
+		if (ret == -1) {
+			fprintf(stderr, "Database %s is corrupted at: %s\n",
+				db_file, subpath);
+			fclose(fp);
+			return;
+		}
+
+		if (bpf_pinning_reserved(pinning)) {
+			fprintf(stderr, "Database %s, id %u is reserved - ignoring!\n",
+				db_file, pinning);
+			continue;
+		}
+
+		entry = malloc(sizeof(*entry));
+		if (!entry) {
+			fprintf(stderr, "No memory left for db entry!\n");
+			continue;
+		}
+
+		entry->pinning = pinning;
+		entry->subpath = strdup(subpath);
+		if (!entry->subpath) {
+			fprintf(stderr, "No memory left for db entry!\n");
+			free(entry);
+			continue;
+		}
+
+		entry->next = ctx->ht[pinning & (ARRAY_SIZE(ctx->ht) - 1)];
+		ctx->ht[pinning & (ARRAY_SIZE(ctx->ht) - 1)] = entry;
+	}
+
+	fclose(fp);
+}
+
+static void bpf_hash_destroy(struct bpf_elf_ctx *ctx)
+{
+	struct bpf_hash_entry *entry;
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(ctx->ht); i++) {
+		while ((entry = ctx->ht[i]) != NULL) {
+			ctx->ht[i] = entry->next;
+			free((char *)entry->subpath);
+			free(entry);
+		}
+	}
+}
+
+static int bpf_elf_check_ehdr(const struct bpf_elf_ctx *ctx)
+{
+	if (ctx->elf_hdr.e_type != ET_REL ||
+	    (ctx->elf_hdr.e_machine != EM_NONE &&
+	     ctx->elf_hdr.e_machine != EM_BPF) ||
+	    ctx->elf_hdr.e_version != EV_CURRENT) {
+		fprintf(stderr, "ELF format error, ELF file not for eBPF?\n");
+		return -EINVAL;
+	}
+
+	switch (ctx->elf_hdr.e_ident[EI_DATA]) {
+	default:
+		fprintf(stderr, "ELF format error, wrong endianness info?\n");
+		return -EINVAL;
+	case ELFDATA2LSB:
+		if (htons(1) == 1) {
+			fprintf(stderr,
+				"We are big endian, eBPF object is little endian!\n");
+			return -EIO;
+		}
+		break;
+	case ELFDATA2MSB:
+		if (htons(1) != 1) {
+			fprintf(stderr,
+				"We are little endian, eBPF object is big endian!\n");
+			return -EIO;
+		}
+		break;
+	}
+
+	return 0;
+}
+
+static void bpf_get_cfg(struct bpf_elf_ctx *ctx)
+{
+	static const char *path_jit = "/proc/sys/net/core/bpf_jit_enable";
+	int fd;
+
+	fd = open(path_jit, O_RDONLY);
+	if (fd >= 0) {
+		char tmp[16] = {};
+
+		if (read(fd, tmp, sizeof(tmp)) > 0)
+			ctx->cfg.jit_enabled = atoi(tmp);
+		close(fd);
+	}
+}
+
+static int bpf_elf_ctx_init(struct bpf_elf_ctx *ctx, const char *pathname,
+			    enum bpf_prog_type type, __u32 ifindex,
+			    bool verbose)
+{
+	uint8_t tmp[20];
+	int ret;
+
+	if (elf_version(EV_CURRENT) == EV_NONE)
+		return -EINVAL;
+
+	bpf_init_env();
+
+	memset(ctx, 0, sizeof(*ctx));
+	bpf_get_cfg(ctx);
+
+	ret = bpf_obj_hash(pathname, tmp, sizeof(tmp));
+	if (ret)
+		ctx->noafalg = true;
+	else
+		hexstring_n2a(tmp, sizeof(tmp), ctx->obj_uid,
+			      sizeof(ctx->obj_uid));
+
+	ctx->verbose = verbose;
+	ctx->type    = type;
+	ctx->ifindex = ifindex;
+
+	ctx->obj_fd = open(pathname, O_RDONLY);
+	if (ctx->obj_fd < 0)
+		return ctx->obj_fd;
+
+	ctx->elf_fd = elf_begin(ctx->obj_fd, ELF_C_READ, NULL);
+	if (!ctx->elf_fd) {
+		ret = -EINVAL;
+		goto out_fd;
+	}
+
+	if (elf_kind(ctx->elf_fd) != ELF_K_ELF) {
+		ret = -EINVAL;
+		goto out_fd;
+	}
+
+	if (gelf_getehdr(ctx->elf_fd, &ctx->elf_hdr) !=
+	    &ctx->elf_hdr) {
+		ret = -EIO;
+		goto out_elf;
+	}
+
+	ret = bpf_elf_check_ehdr(ctx);
+	if (ret < 0)
+		goto out_elf;
+
+	ctx->sec_done = calloc(ctx->elf_hdr.e_shnum,
+			       sizeof(*(ctx->sec_done)));
+	if (!ctx->sec_done) {
+		ret = -ENOMEM;
+		goto out_elf;
+	}
+
+	if (ctx->verbose && bpf_log_realloc(ctx)) {
+		ret = -ENOMEM;
+		goto out_free;
+	}
+
+	bpf_save_finfo(ctx);
+	bpf_hash_init(ctx, CONFDIR "/bpf_pinning");
+
+	return 0;
+out_free:
+	free(ctx->sec_done);
+out_elf:
+	elf_end(ctx->elf_fd);
+out_fd:
+	close(ctx->obj_fd);
+	return ret;
+}
+
+static int bpf_maps_count(struct bpf_elf_ctx *ctx)
+{
+	int i, count = 0;
+
+	for (i = 0; i < ARRAY_SIZE(ctx->map_fds); i++) {
+		if (!ctx->map_fds[i])
+			break;
+		count++;
+	}
+
+	return count;
+}
+
+static void bpf_maps_teardown(struct bpf_elf_ctx *ctx)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(ctx->map_fds); i++) {
+		if (ctx->map_fds[i])
+			close(ctx->map_fds[i]);
+	}
+
+	if (ctx->btf_fd)
+		close(ctx->btf_fd);
+	free(ctx->btf.types);
+}
+
+static void bpf_elf_ctx_destroy(struct bpf_elf_ctx *ctx, bool failure)
+{
+	if (failure)
+		bpf_maps_teardown(ctx);
+
+	bpf_hash_destroy(ctx);
+
+	free(ctx->prog_text.insns);
+	free(ctx->sec_done);
+	free(ctx->log);
+
+	elf_end(ctx->elf_fd);
+	close(ctx->obj_fd);
+}
+
+static struct bpf_elf_ctx __ctx;
+
+static int bpf_obj_open(const char *pathname, enum bpf_prog_type type,
+			const char *section, __u32 ifindex, bool verbose)
+{
+	struct bpf_elf_ctx *ctx = &__ctx;
+	int fd = 0, ret;
+
+	ret = bpf_elf_ctx_init(ctx, pathname, type, ifindex, verbose);
+	if (ret < 0) {
+		fprintf(stderr, "Cannot initialize ELF context!\n");
+		return ret;
+	}
+
+	ret = bpf_fetch_ancillary(ctx, strcmp(section, ".text"));
+	if (ret < 0) {
+		fprintf(stderr, "Error fetching ELF ancillary data!\n");
+		goto out;
+	}
+
+	fd = bpf_fetch_prog_sec(ctx, section);
+	if (fd < 0) {
+		fprintf(stderr, "Error fetching program/map!\n");
+		ret = fd;
+		goto out;
+	}
+
+	ret = bpf_fill_prog_arrays(ctx);
+	if (ret < 0)
+		fprintf(stderr, "Error filling program arrays!\n");
+out:
+	bpf_elf_ctx_destroy(ctx, ret < 0);
+	if (ret < 0) {
+		if (fd >= 0)
+			close(fd);
+		return ret;
+	}
+
+	return fd;
+}
+
+static int
+bpf_map_set_send(int fd, struct sockaddr_un *addr, unsigned int addr_len,
+		 const struct bpf_map_data *aux, unsigned int entries)
+{
+	struct bpf_map_set_msg msg = {
+		.aux.uds_ver = BPF_SCM_AUX_VER,
+		.aux.num_ent = entries,
+	};
+	int *cmsg_buf, min_fd;
+	char *amsg_buf;
+	int i;
+
+	strlcpy(msg.aux.obj_name, aux->obj, sizeof(msg.aux.obj_name));
+	memcpy(&msg.aux.obj_st, aux->st, sizeof(msg.aux.obj_st));
+
+	cmsg_buf = bpf_map_set_init(&msg, addr, addr_len);
+	amsg_buf = (char *)msg.aux.ent;
+
+	for (i = 0; i < entries; i += min_fd) {
+		int ret;
+
+		min_fd = min(BPF_SCM_MAX_FDS * 1U, entries - i);
+		bpf_map_set_init_single(&msg, min_fd);
+
+		memcpy(cmsg_buf, &aux->fds[i], sizeof(aux->fds[0]) * min_fd);
+		memcpy(amsg_buf, &aux->ent[i], sizeof(aux->ent[0]) * min_fd);
+
+		ret = sendmsg(fd, &msg.hdr, 0);
+		if (ret <= 0)
+			return ret ? : -1;
+	}
+
+	return 0;
+}
+
+static int
+bpf_map_set_recv(int fd, int *fds,  struct bpf_map_aux *aux,
+		 unsigned int entries)
+{
+	struct bpf_map_set_msg msg;
+	int *cmsg_buf, min_fd;
+	char *amsg_buf, *mmsg_buf;
+	unsigned int needed = 1;
+	int i;
+
+	cmsg_buf = bpf_map_set_init(&msg, NULL, 0);
+	amsg_buf = (char *)msg.aux.ent;
+	mmsg_buf = (char *)&msg.aux;
+
+	for (i = 0; i < min(entries, needed); i += min_fd) {
+		struct cmsghdr *cmsg;
+		int ret;
+
+		min_fd = min(entries, entries - i);
+		bpf_map_set_init_single(&msg, min_fd);
+
+		ret = recvmsg(fd, &msg.hdr, 0);
+		if (ret <= 0)
+			return ret ? : -1;
+
+		cmsg = CMSG_FIRSTHDR(&msg.hdr);
+		if (!cmsg || cmsg->cmsg_type != SCM_RIGHTS)
+			return -EINVAL;
+		if (msg.hdr.msg_flags & MSG_CTRUNC)
+			return -EIO;
+		if (msg.aux.uds_ver != BPF_SCM_AUX_VER)
+			return -ENOSYS;
+
+		min_fd = (cmsg->cmsg_len - sizeof(*cmsg)) / sizeof(fd);
+		if (min_fd > entries || min_fd <= 0)
+			return -EINVAL;
+
+		memcpy(&fds[i], cmsg_buf, sizeof(fds[0]) * min_fd);
+		memcpy(&aux->ent[i], amsg_buf, sizeof(aux->ent[0]) * min_fd);
+		memcpy(aux, mmsg_buf, offsetof(struct bpf_map_aux, ent));
+
+		needed = aux->num_ent;
+	}
+
+	return 0;
+}
+
+int bpf_send_map_fds(const char *path, const char *obj)
+{
+	struct bpf_elf_ctx *ctx = &__ctx;
+	struct sockaddr_un addr = { .sun_family = AF_UNIX };
+	struct bpf_map_data bpf_aux = {
+		.fds = ctx->map_fds,
+		.ent = ctx->maps,
+		.st  = &ctx->stat,
+		.obj = obj,
+	};
+	int fd, ret = -1;
+
+	fd = socket(AF_UNIX, SOCK_DGRAM, 0);
+	if (fd < 0) {
+		fprintf(stderr, "Cannot open socket: %s\n",
+			strerror(errno));
+		goto out;
+	}
+
+	strlcpy(addr.sun_path, path, sizeof(addr.sun_path));
+
+	ret = connect(fd, (struct sockaddr *)&addr, sizeof(addr));
+	if (ret < 0) {
+		fprintf(stderr, "Cannot connect to %s: %s\n",
+			path, strerror(errno));
+		goto out;
+	}
+
+	ret = bpf_map_set_send(fd, &addr, sizeof(addr), &bpf_aux,
+			       bpf_maps_count(ctx));
+	if (ret < 0)
+		fprintf(stderr, "Cannot send fds to %s: %s\n",
+			path, strerror(errno));
+
+	bpf_maps_teardown(ctx);
+out:
+	if (fd >= 0)
+		close(fd);
+	return ret;
+}
+
+int bpf_recv_map_fds(const char *path, int *fds, struct bpf_map_aux *aux,
+		     unsigned int entries)
+{
+	struct sockaddr_un addr = { .sun_family = AF_UNIX };
+	int fd, ret = -1;
+
+	fd = socket(AF_UNIX, SOCK_DGRAM, 0);
+	if (fd < 0) {
+		fprintf(stderr, "Cannot open socket: %s\n",
+			strerror(errno));
+		goto out;
+	}
+
+	strlcpy(addr.sun_path, path, sizeof(addr.sun_path));
+
+	ret = bind(fd, (struct sockaddr *)&addr, sizeof(addr));
+	if (ret < 0) {
+		fprintf(stderr, "Cannot bind to socket: %s\n",
+			strerror(errno));
+		goto out;
+	}
+
+	ret = bpf_map_set_recv(fd, fds, aux, entries);
+	if (ret < 0)
+		fprintf(stderr, "Cannot recv fds from %s: %s\n",
+			path, strerror(errno));
+
+	unlink(addr.sun_path);
+
+out:
+	if (fd >= 0)
+		close(fd);
+	return ret;
+}
+
+#ifdef HAVE_LIBBPF
+/* The following functions are wrapper functions for libbpf code to be
+ * compatible with the legacy format. So all the functions have prefix
+ * with iproute2_
+ */
+int iproute2_bpf_elf_ctx_init(struct bpf_cfg_in *cfg)
+{
+	struct bpf_elf_ctx *ctx = &__ctx;
+
+	return bpf_elf_ctx_init(ctx, cfg->object, cfg->type, cfg->ifindex, cfg->verbose);
+}
+
+int iproute2_bpf_fetch_ancillary(void)
+{
+	struct bpf_elf_ctx *ctx = &__ctx;
+	struct bpf_elf_sec_data data;
+	int i, ret = 0;
+
+	for (i = 1; i < ctx->elf_hdr.e_shnum; i++) {
+		ret = bpf_fill_section_data(ctx, i, &data);
+		if (ret < 0)
+			continue;
+
+		if (data.sec_hdr.sh_type == SHT_PROGBITS &&
+		    !strcmp(data.sec_name, ELF_SECTION_MAPS))
+			ret = bpf_fetch_maps_begin(ctx, i, &data);
+		else if (data.sec_hdr.sh_type == SHT_SYMTAB &&
+			 !strcmp(data.sec_name, ".symtab"))
+			ret = bpf_fetch_symtab(ctx, i, &data);
+		else if (data.sec_hdr.sh_type == SHT_STRTAB &&
+			 !strcmp(data.sec_name, ".strtab"))
+			ret = bpf_fetch_strtab(ctx, i, &data);
+		if (ret < 0) {
+			fprintf(stderr, "Error parsing section %d! Perhaps check with readelf -a?\n",
+				i);
+			return ret;
+		}
+	}
+
+	if (bpf_has_map_data(ctx)) {
+		ret = bpf_fetch_maps_end(ctx);
+		if (ret < 0) {
+			fprintf(stderr, "Error fixing up map structure, incompatible struct bpf_elf_map used?\n");
+			return ret;
+		}
+	}
+
+	return ret;
+}
+
+int iproute2_get_root_path(char *root_path, size_t len)
+{
+	struct bpf_elf_ctx *ctx = &__ctx;
+	int ret = 0;
+
+	snprintf(root_path, len, "%s/%s",
+		 bpf_get_work_dir(ctx->type), BPF_DIR_GLOBALS);
+
+	ret = mkdir(root_path, S_IRWXU);
+	if (ret && errno != EEXIST) {
+		fprintf(stderr, "mkdir %s failed: %s\n", root_path, strerror(errno));
+		return ret;
+	}
+
+	return 0;
+}
+
+bool iproute2_is_pin_map(const char *libbpf_map_name, char *pathname)
+{
+	struct bpf_elf_ctx *ctx = &__ctx;
+	const char *map_name, *tmp;
+	unsigned int pinning;
+	int i, ret = 0;
+
+	for (i = 0; i < ctx->map_num; i++) {
+		if (ctx->maps[i].pinning == PIN_OBJECT_NS &&
+		    ctx->noafalg) {
+			fprintf(stderr, "Missing kernel AF_ALG support for PIN_OBJECT_NS!\n");
+			return false;
+		}
+
+		map_name = bpf_map_fetch_name(ctx, i);
+		if (!map_name) {
+			return false;
+		}
+
+		if (strcmp(libbpf_map_name, map_name))
+			continue;
+
+		pinning = ctx->maps[i].pinning;
+
+		if (bpf_no_pinning(ctx, pinning) || !bpf_get_work_dir(ctx->type))
+			return false;
+
+		if (pinning == PIN_OBJECT_NS)
+			ret = bpf_make_obj_path(ctx);
+		else if ((tmp = bpf_custom_pinning(ctx, pinning)))
+			ret = bpf_make_custom_path(ctx, tmp);
+		if (ret < 0)
+			return false;
+
+		bpf_make_pathname(pathname, PATH_MAX, map_name, ctx, pinning);
+
+		return true;
+	}
+
+	return false;
+}
+
+bool iproute2_is_map_in_map(const char *libbpf_map_name, struct bpf_elf_map *imap,
+			    struct bpf_elf_map *omap, char *omap_name)
+{
+	struct bpf_elf_ctx *ctx = &__ctx;
+	const char *inner_map_name, *outer_map_name;
+	int i, j;
+
+	for (i = 0; i < ctx->map_num; i++) {
+		inner_map_name = bpf_map_fetch_name(ctx, i);
+		if (!inner_map_name) {
+			return false;
+		}
+
+		if (strcmp(libbpf_map_name, inner_map_name))
+			continue;
+
+		if (!ctx->maps[i].id ||
+		    ctx->maps[i].inner_id)
+			continue;
+
+		*imap = ctx->maps[i];
+
+		for (j = 0; j < ctx->map_num; j++) {
+			if (!bpf_is_map_in_map_type(&ctx->maps[j]))
+				continue;
+			if (ctx->maps[j].inner_id != ctx->maps[i].id)
+				continue;
+
+			*omap = ctx->maps[j];
+			outer_map_name = bpf_map_fetch_name(ctx, j);
+			if (!outer_map_name)
+				return false;
+
+			memcpy(omap_name, outer_map_name, strlen(outer_map_name) + 1);
+
+			return true;
+		}
+	}
+
+	return false;
+}
+
+int iproute2_find_map_name_by_id(unsigned int map_id, char *name)
+{
+	struct bpf_elf_ctx *ctx = &__ctx;
+	const char *map_name;
+	int i, idx = -1;
+
+	for (i = 0; i < ctx->map_num; i++) {
+		if (ctx->maps[i].id == map_id &&
+		    ctx->maps[i].type == BPF_MAP_TYPE_PROG_ARRAY) {
+			idx = i;
+			break;
+		}
+	}
+
+	if (idx < 0)
+		return -1;
+
+	map_name = bpf_map_fetch_name(ctx, idx);
+	if (!map_name)
+		return -1;
+
+	memcpy(name, map_name, strlen(map_name) + 1);
+	return 0;
+}
+#endif /* HAVE_LIBBPF */
+#endif /* HAVE_ELF */
diff --git a/lib/bpf_libbpf.c b/lib/bpf_libbpf.c
new file mode 100644
index 0000000..e1c211a
--- /dev/null
+++ b/lib/bpf_libbpf.c
@@ -0,0 +1,383 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * bpf_libbpf.c		BPF code relay on libbpf
+ * Authors:		Hangbin Liu <haliu@redhat.com>
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
+
+#include <libelf.h>
+#include <gelf.h>
+
+#include <bpf/libbpf.h>
+#include <bpf/bpf.h>
+
+#include "bpf_util.h"
+
+static int __attribute__((format(printf, 2, 0)))
+verbose_print(enum libbpf_print_level level, const char *format, va_list args)
+{
+	return vfprintf(stderr, format, args);
+}
+
+static int __attribute__((format(printf, 2, 0)))
+silent_print(enum libbpf_print_level level, const char *format, va_list args)
+{
+	if (level > LIBBPF_WARN)
+		return 0;
+
+	/* Skip warning from bpf_object__init_user_maps() for legacy maps */
+	if (strstr(format, "has unrecognized, non-zero options"))
+		return 0;
+
+	return vfprintf(stderr, format, args);
+}
+
+static const char *get_bpf_program__section_name(const struct bpf_program *prog)
+{
+#ifdef HAVE_LIBBPF_SECTION_NAME
+	return bpf_program__section_name(prog);
+#else
+	return bpf_program__title(prog, false);
+#endif
+}
+
+static int create_map(const char *name, struct bpf_elf_map *map,
+		      __u32 ifindex, int inner_fd)
+{
+	union bpf_attr attr = {};
+
+	attr.map_type = map->type;
+	strlcpy(attr.map_name, name, sizeof(attr.map_name));
+	attr.map_flags = map->flags;
+	attr.key_size = map->size_key;
+	attr.value_size = map->size_value;
+	attr.max_entries = map->max_elem;
+	attr.map_ifindex = ifindex;
+	attr.inner_map_fd = inner_fd;
+
+	return bpf(BPF_MAP_CREATE, &attr, sizeof(attr));
+}
+
+static int create_map_in_map(struct bpf_object *obj, struct bpf_map *map,
+			     struct bpf_elf_map *elf_map, int inner_fd,
+			     bool *reuse_pin_map)
+{
+	char pathname[PATH_MAX];
+	const char *map_name;
+	bool pin_map = false;
+	int map_fd, ret = 0;
+
+	map_name = bpf_map__name(map);
+
+	if (iproute2_is_pin_map(map_name, pathname)) {
+		pin_map = true;
+
+		/* Check if there already has a pinned map */
+		map_fd = bpf_obj_get(pathname);
+		if (map_fd > 0) {
+			if (reuse_pin_map)
+				*reuse_pin_map = true;
+			close(map_fd);
+			return bpf_map__set_pin_path(map, pathname);
+		}
+	}
+
+	map_fd = create_map(map_name, elf_map, bpf_map__ifindex(map), inner_fd);
+	if (map_fd < 0) {
+		fprintf(stderr, "create map %s failed\n", map_name);
+		return map_fd;
+	}
+
+	ret = bpf_map__reuse_fd(map, map_fd);
+	if (ret < 0) {
+		fprintf(stderr, "map %s reuse fd failed\n", map_name);
+		goto err_out;
+	}
+
+	if (pin_map) {
+		ret = bpf_map__set_pin_path(map, pathname);
+		if (ret < 0)
+			goto err_out;
+	}
+
+	return 0;
+err_out:
+	close(map_fd);
+	return ret;
+}
+
+static int
+handle_legacy_map_in_map(struct bpf_object *obj, struct bpf_map *inner_map,
+			 const char *inner_map_name)
+{
+	int inner_fd, outer_fd, inner_idx, ret = 0;
+	struct bpf_elf_map imap, omap;
+	struct bpf_map *outer_map;
+	/* What's the size limit of map name? */
+	char outer_map_name[128];
+	bool reuse_pin_map = false;
+
+	/* Deal with map-in-map */
+	if (iproute2_is_map_in_map(inner_map_name, &imap, &omap, outer_map_name)) {
+		ret = create_map_in_map(obj, inner_map, &imap, -1, NULL);
+		if (ret < 0)
+			return ret;
+
+		inner_fd = bpf_map__fd(inner_map);
+		outer_map = bpf_object__find_map_by_name(obj, outer_map_name);
+		ret = create_map_in_map(obj, outer_map, &omap, inner_fd, &reuse_pin_map);
+		if (ret < 0)
+			return ret;
+
+		if (!reuse_pin_map) {
+			inner_idx = imap.inner_idx;
+			outer_fd = bpf_map__fd(outer_map);
+			ret = bpf_map_update_elem(outer_fd, &inner_idx, &inner_fd, 0);
+			if (ret < 0)
+				fprintf(stderr, "Cannot update inner_idx into outer_map\n");
+		}
+	}
+
+	return ret;
+}
+
+static int find_legacy_tail_calls(struct bpf_program *prog, struct bpf_object *obj,
+				  struct bpf_map **pmap)
+{
+	unsigned int map_id, key_id;
+	const char *sec_name;
+	struct bpf_map *map;
+	char map_name[128];
+	int ret;
+
+	/* Handle iproute2 tail call */
+	sec_name = get_bpf_program__section_name(prog);
+	ret = sscanf(sec_name, "%i/%i", &map_id, &key_id);
+	if (ret != 2)
+		return -1;
+
+	ret = iproute2_find_map_name_by_id(map_id, map_name);
+	if (ret < 0) {
+		fprintf(stderr, "unable to find map id %u for tail call\n", map_id);
+		return ret;
+	}
+
+	map = bpf_object__find_map_by_name(obj, map_name);
+	if (!map)
+		return -1;
+
+	if (pmap)
+		*pmap = map;
+
+	return 0;
+}
+
+static int update_legacy_tail_call_maps(struct bpf_object *obj)
+{
+	int prog_fd, map_fd, ret = 0;
+	unsigned int map_id, key_id;
+	struct bpf_program *prog;
+	const char *sec_name;
+	struct bpf_map *map;
+
+	bpf_object__for_each_program(prog, obj) {
+		/* load_bpf_object has already verified find_legacy_tail_calls
+		 * succeeds when it should
+		 */
+		if (find_legacy_tail_calls(prog, obj, &map) < 0)
+			continue;
+
+		prog_fd = bpf_program__fd(prog);
+		if (prog_fd < 0)
+			continue;
+
+		sec_name = get_bpf_program__section_name(prog);
+		ret = sscanf(sec_name, "%i/%i", &map_id, &key_id);
+		if (ret != 2)
+			continue;
+
+		map_fd = bpf_map__fd(map);
+		ret = bpf_map_update_elem(map_fd, &key_id, &prog_fd, 0);
+		if (ret < 0) {
+			fprintf(stderr, "Cannot update map key for tail call!\n");
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+static int handle_legacy_maps(struct bpf_object *obj)
+{
+	char pathname[PATH_MAX];
+	struct bpf_map *map;
+	const char *map_name;
+	int map_fd, ret = 0;
+
+	bpf_object__for_each_map(map, obj) {
+		map_name = bpf_map__name(map);
+
+		ret = handle_legacy_map_in_map(obj, map, map_name);
+		if (ret)
+			return ret;
+
+		/* If it is a iproute2 legacy pin maps, just set pin path
+		 * and let bpf_object__load() to deal with the map creation.
+		 * We need to ignore map-in-maps which have pinned maps manually
+		 */
+		map_fd = bpf_map__fd(map);
+		if (map_fd < 0 && iproute2_is_pin_map(map_name, pathname)) {
+			ret = bpf_map__set_pin_path(map, pathname);
+			if (ret) {
+				fprintf(stderr, "map '%s': couldn't set pin path.\n", map_name);
+				break;
+			}
+		}
+
+	}
+
+	return ret;
+}
+
+static bool bpf_map_is_offload_neutral(const struct bpf_map *map)
+{
+	return bpf_map__type(map) == BPF_MAP_TYPE_PERF_EVENT_ARRAY;
+}
+
+static bool find_prog_to_attach(struct bpf_program *prog,
+				struct bpf_program *exist_prog,
+				const char *section, const char *prog_name)
+{
+	if (exist_prog)
+		return false;
+
+	/* We have default section name 'prog'. So do not check
+	 * section name if there already has program name.
+	 */
+	if (prog_name)
+		return !strcmp(bpf_program__name(prog), prog_name);
+	else
+		return !strcmp(get_bpf_program__section_name(prog), section);
+}
+
+static int load_bpf_object(struct bpf_cfg_in *cfg)
+{
+	struct bpf_program *p, *prog = NULL;
+	struct bpf_object *obj;
+	char root_path[PATH_MAX];
+	struct bpf_map *map;
+	int prog_fd, ret = 0;
+
+	ret = iproute2_get_root_path(root_path, PATH_MAX);
+	if (ret)
+		return ret;
+
+	DECLARE_LIBBPF_OPTS(bpf_object_open_opts, open_opts,
+			.relaxed_maps = true,
+			.pin_root_path = root_path,
+	);
+
+	obj = bpf_object__open_file(cfg->object, &open_opts);
+	if (libbpf_get_error(obj)) {
+		fprintf(stderr, "ERROR: opening BPF object file failed\n");
+		return -ENOENT;
+	}
+
+	bpf_object__for_each_program(p, obj) {
+		bool prog_to_attach = find_prog_to_attach(p, prog,
+							  cfg->section,
+							  cfg->prog_name);
+
+		/* Only load the programs that will either be subsequently
+		 * attached or inserted into a tail call map */
+		if (find_legacy_tail_calls(p, obj, NULL) < 0 &&
+		    !prog_to_attach) {
+			ret = bpf_program__set_autoload(p, false);
+			if (ret)
+				return -EINVAL;
+			continue;
+		}
+
+		bpf_program__set_type(p, cfg->type);
+		bpf_program__set_ifindex(p, cfg->ifindex);
+
+		if (prog_to_attach)
+			prog = p;
+	}
+
+	bpf_object__for_each_map(map, obj) {
+		if (!bpf_map_is_offload_neutral(map))
+			bpf_map__set_ifindex(map, cfg->ifindex);
+	}
+
+	if (!prog) {
+		if (cfg->prog_name)
+			fprintf(stderr, "object file doesn't contain prog %s\n", cfg->prog_name);
+		else
+			fprintf(stderr, "object file doesn't contain sec %s\n", cfg->section);
+		return -ENOENT;
+	}
+
+	/* Handle iproute2 legacy pin maps and map-in-maps */
+	ret = handle_legacy_maps(obj);
+	if (ret)
+		goto unload_obj;
+
+	ret = bpf_object__load(obj);
+	if (ret)
+		goto unload_obj;
+
+	ret = update_legacy_tail_call_maps(obj);
+	if (ret)
+		goto unload_obj;
+
+	prog_fd = fcntl(bpf_program__fd(prog), F_DUPFD_CLOEXEC, 1);
+	if (prog_fd < 0)
+		ret = -errno;
+	else
+		cfg->prog_fd = prog_fd;
+
+unload_obj:
+	/* Close obj as we don't need it */
+	bpf_object__close(obj);
+	return ret;
+}
+
+/* Load ebpf and return prog fd */
+int iproute2_load_libbpf(struct bpf_cfg_in *cfg)
+{
+	int ret = 0;
+
+	if (cfg->verbose)
+		libbpf_set_print(verbose_print);
+	else
+		libbpf_set_print(silent_print);
+
+	ret = iproute2_bpf_elf_ctx_init(cfg);
+	if (ret < 0) {
+		fprintf(stderr, "Cannot initialize ELF context!\n");
+		return ret;
+	}
+
+	ret = iproute2_bpf_fetch_ancillary();
+	if (ret < 0) {
+		fprintf(stderr, "Error fetching ELF ancillary data!\n");
+		return ret;
+	}
+
+	ret = load_bpf_object(cfg);
+	if (ret)
+		return ret;
+
+	return cfg->prog_fd;
+}
diff --git a/lib/cg_map.c b/lib/cg_map.c
new file mode 100644
index 0000000..39f244d
--- /dev/null
+++ b/lib/cg_map.c
@@ -0,0 +1,134 @@
+/*
+ * cg_map.c	cgroup v2 cache
+ *
+ *		This program is free software; you can redistribute it and/or
+ *		modify it under the terms of the GNU General Public License
+ *		as published by the Free Software Foundation; either version
+ *		2 of the License, or (at your option) any later version.
+ *
+ * Authors:	Dmitry Yakunin <zeil@yandex-team.ru>
+ */
+
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include <stdbool.h>
+#include <linux/types.h>
+#include <linux/limits.h>
+#include <ftw.h>
+
+#include "cg_map.h"
+#include "list.h"
+#include "utils.h"
+
+struct cg_cache {
+	struct hlist_node id_hash;
+	__u64	id;
+	char	path[];
+};
+
+#define IDMAP_SIZE	1024
+static struct hlist_head id_head[IDMAP_SIZE];
+
+static struct cg_cache *cg_get_by_id(__u64 id)
+{
+	unsigned int h = id & (IDMAP_SIZE - 1);
+	struct hlist_node *n;
+
+	hlist_for_each(n, &id_head[h]) {
+		struct cg_cache *cg;
+
+		cg = container_of(n, struct cg_cache, id_hash);
+		if (cg->id == id)
+			return cg;
+	}
+
+	return NULL;
+}
+
+static struct cg_cache *cg_entry_create(__u64 id, const char *path)
+{
+	unsigned int h = id & (IDMAP_SIZE - 1);
+	struct cg_cache *cg;
+
+	cg = malloc(sizeof(*cg) + strlen(path) + 1);
+	if (!cg) {
+		fprintf(stderr,
+			"Failed to allocate memory for cgroup2 cache entry");
+		return NULL;
+	}
+	cg->id = id;
+	strcpy(cg->path, path);
+
+	hlist_add_head(&cg->id_hash, &id_head[h]);
+
+	return cg;
+}
+
+static int mntlen;
+
+static int nftw_fn(const char *fpath, const struct stat *sb,
+		   int typeflag, struct FTW *ftw)
+{
+	const char *path;
+	__u64 id;
+
+	if (typeflag != FTW_D)
+		return 0;
+
+	id = get_cgroup2_id(fpath);
+	if (!id)
+		return -1;
+
+	path = fpath + mntlen;
+	if (*path == '\0')
+		/* root cgroup */
+		path = "/";
+	if (!cg_entry_create(id, path))
+		return -1;
+
+	return 0;
+}
+
+static void cg_init_map(void)
+{
+	char *mnt;
+
+	mnt = find_cgroup2_mount(false);
+	if (!mnt)
+		return;
+
+	mntlen = strlen(mnt);
+	(void) nftw(mnt, nftw_fn, 1024, FTW_MOUNT);
+
+	free(mnt);
+}
+
+const char *cg_id_to_path(__u64 id)
+{
+	static int initialized;
+	static char buf[64];
+
+	const struct cg_cache *cg;
+	char *path;
+
+	if (!initialized) {
+		cg_init_map();
+		initialized = 1;
+	}
+
+	cg = cg_get_by_id(id);
+	if (cg)
+		return cg->path;
+
+	path = get_cgroup2_path(id, false);
+	if (path) {
+		cg = cg_entry_create(id, path);
+		free(path);
+		if (cg)
+			return cg->path;
+	}
+
+	snprintf(buf, sizeof(buf), "unreachable:%llx", id);
+	return buf;
+}
diff --git a/lib/color.c b/lib/color.c
new file mode 100644
index 0000000..5997684
--- /dev/null
+++ b/lib/color.c
@@ -0,0 +1,183 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#include <stdio.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <linux/if.h>
+
+#include "color.h"
+#include "utils.h"
+
+static void set_color_palette(void);
+
+enum color {
+	C_RED,
+	C_GREEN,
+	C_YELLOW,
+	C_BLUE,
+	C_MAGENTA,
+	C_CYAN,
+	C_WHITE,
+	C_BOLD_RED,
+	C_BOLD_GREEN,
+	C_BOLD_YELLOW,
+	C_BOLD_BLUE,
+	C_BOLD_MAGENTA,
+	C_BOLD_CYAN,
+	C_BOLD_WHITE,
+	C_CLEAR
+};
+
+static const char * const color_codes[] = {
+	"\e[31m",
+	"\e[32m",
+	"\e[33m",
+	"\e[34m",
+	"\e[35m",
+	"\e[36m",
+	"\e[37m",
+	"\e[1;31m",
+	"\e[1;32m",
+	"\e[1;33m",
+	"\e[1;34m",
+	"\e[1;35m",
+	"\e[1;36m",
+	"\e[1;37m",
+	"\e[0m",
+	NULL,
+};
+
+/* light background */
+static enum color attr_colors_light[] = {
+	C_CYAN,
+	C_YELLOW,
+	C_MAGENTA,
+	C_BLUE,
+	C_GREEN,
+	C_RED,
+	C_CLEAR,
+};
+
+/* dark background */
+static enum color attr_colors_dark[] = {
+	C_BOLD_CYAN,
+	C_BOLD_YELLOW,
+	C_BOLD_MAGENTA,
+	C_BOLD_BLUE,
+	C_BOLD_GREEN,
+	C_BOLD_RED,
+	C_CLEAR
+};
+
+static int is_dark_bg;
+static int color_is_enabled;
+
+static void enable_color(void)
+{
+	color_is_enabled = 1;
+	set_color_palette();
+}
+
+bool check_enable_color(int color, int json)
+{
+	if (json || color == COLOR_OPT_NEVER)
+		return false;
+
+	if (color == COLOR_OPT_ALWAYS || isatty(fileno(stdout))) {
+		enable_color();
+		return true;
+	}
+	return false;
+}
+
+bool matches_color(const char *arg, int *val)
+{
+	char *dup, *p;
+
+	if (!val)
+		return false;
+
+	dup = strdupa(arg);
+	p = strchrnul(dup, '=');
+	if (*p)
+		*(p++) = '\0';
+
+	if (matches(dup, "-color"))
+		return false;
+
+	if (*p == '\0' || !strcmp(p, "always"))
+		*val = COLOR_OPT_ALWAYS;
+	else if (!strcmp(p, "auto"))
+		*val = COLOR_OPT_AUTO;
+	else if (!strcmp(p, "never"))
+		*val = COLOR_OPT_NEVER;
+	else
+		return false;
+	return true;
+}
+
+static void set_color_palette(void)
+{
+	char *p = getenv("COLORFGBG");
+
+	/*
+	 * COLORFGBG environment variable usually contains either two or three
+	 * values separated by semicolons; we want the last value in either case.
+	 * If this value is 0-6 or 8, background is dark.
+	 */
+	if (p && (p = strrchr(p, ';')) != NULL
+		&& ((p[1] >= '0' && p[1] <= '6') || p[1] == '8')
+		&& p[2] == '\0')
+		is_dark_bg = 1;
+}
+
+__attribute__((format(printf, 3, 4)))
+int color_fprintf(FILE *fp, enum color_attr attr, const char *fmt, ...)
+{
+	int ret = 0;
+	va_list args;
+
+	va_start(args, fmt);
+
+	if (!color_is_enabled || attr == COLOR_NONE) {
+		ret = vfprintf(fp, fmt, args);
+		goto end;
+	}
+
+	ret += fprintf(fp, "%s", color_codes[is_dark_bg ?
+		attr_colors_dark[attr] : attr_colors_light[attr]]);
+
+	ret += vfprintf(fp, fmt, args);
+	ret += fprintf(fp, "%s", color_codes[C_CLEAR]);
+
+end:
+	va_end(args);
+	return ret;
+}
+
+enum color_attr ifa_family_color(__u8 ifa_family)
+{
+	switch (ifa_family) {
+	case AF_INET:
+		return COLOR_INET;
+	case AF_INET6:
+		return COLOR_INET6;
+	default:
+		return COLOR_NONE;
+	}
+}
+
+enum color_attr oper_state_color(__u8 state)
+{
+	switch (state) {
+	case IF_OPER_UP:
+		return COLOR_OPERSTATE_UP;
+	case IF_OPER_DOWN:
+		return COLOR_OPERSTATE_DOWN;
+	default:
+		return COLOR_NONE;
+	}
+}
diff --git a/lib/coverity_model.c b/lib/coverity_model.c
new file mode 100644
index 0000000..1321fe8
--- /dev/null
+++ b/lib/coverity_model.c
@@ -0,0 +1,17 @@
+/*
+ * Coverity Scan model
+ *
+ * This is a modeling file for Coverity Scan. Modeling helps to avoid false
+ * positives.
+ *
+ * - A model file can't import any header files.
+ * - Therefore only some built-in primitives like int, char and void are
+ *   available but not wchar_t, NULL etc.
+ * - Modeling doesn't need full structs and typedefs. Rudimentary structs
+ *   and similar types are sufficient.
+ * - An uninitialized local pointer is not an error. It signifies that the
+ *   variable could be either NULL or have some data.
+ *
+ * Coverity Scan doesn't pick up modifications automatically. The model file
+ * must be uploaded by an admin.
+ */
diff --git a/lib/exec.c b/lib/exec.c
new file mode 100644
index 0000000..9b1c8f4
--- /dev/null
+++ b/lib/exec.c
@@ -0,0 +1,46 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#include <sys/wait.h>
+#include <stdio.h>
+#include <errno.h>
+#include <unistd.h>
+
+#include "utils.h"
+#include "namespace.h"
+
+int cmd_exec(const char *cmd, char **argv, bool do_fork,
+	     int (*setup)(void *), void *arg)
+{
+	fflush(stdout);
+	if (do_fork) {
+		int status;
+		pid_t pid;
+
+		pid = fork();
+		if (pid < 0) {
+			perror("fork");
+			exit(1);
+		}
+
+		if (pid != 0) {
+			/* Parent  */
+			if (waitpid(pid, &status, 0) < 0) {
+				perror("waitpid");
+				exit(1);
+			}
+
+			if (WIFEXITED(status)) {
+				return WEXITSTATUS(status);
+			}
+
+			exit(1);
+		}
+	}
+
+	if (setup && setup(arg))
+		return -1;
+
+	if (execvp(cmd, argv)  < 0)
+		fprintf(stderr, "exec of \"%s\" failed: %s\n",
+				cmd, strerror(errno));
+	_exit(1);
+}
diff --git a/lib/fs.c b/lib/fs.c
new file mode 100644
index 0000000..3752931
--- /dev/null
+++ b/lib/fs.c
@@ -0,0 +1,369 @@
+/*
+ * fs.c         filesystem APIs
+ *
+ *		This program is free software; you can redistribute it and/or
+ *		modify it under the terms of the GNU General Public License
+ *		as published by the Free Software Foundation; either version
+ *		2 of the License, or (at your option) any later version.
+ *
+ * Authors:	David Ahern <dsa@cumulusnetworks.com>
+ *
+ */
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/socket.h>
+#include <sys/mount.h>
+#include <ctype.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <errno.h>
+#include <limits.h>
+
+#include "utils.h"
+
+#ifndef HAVE_HANDLE_AT
+# include <sys/syscall.h>
+#endif
+
+#define CGROUP2_FS_NAME "cgroup2"
+
+/* if not already mounted cgroup2 is mounted here for iproute2's use */
+#define MNT_CGRP2_PATH  "/var/run/cgroup2"
+
+
+#ifndef HAVE_HANDLE_AT
+struct file_handle {
+	unsigned handle_bytes;
+	int handle_type;
+	unsigned char f_handle[];
+};
+
+static int name_to_handle_at(int dirfd, const char *pathname,
+	struct file_handle *handle, int *mount_id, int flags)
+{
+	return syscall(__NR_name_to_handle_at, dirfd, pathname, handle,
+	               mount_id, flags);
+}
+
+static int open_by_handle_at(int mount_fd, struct file_handle *handle, int flags)
+{
+	return syscall(__NR_open_by_handle_at, mount_fd, handle, flags);
+}
+#endif
+
+/* return mount path of first occurrence of given fstype */
+static char *find_fs_mount(const char *fs_to_find)
+{
+	char path[4096];
+	char fstype[128];    /* max length of any filesystem name */
+	char *mnt = NULL;
+	FILE *fp;
+
+	fp = fopen("/proc/mounts", "r");
+	if (!fp) {
+		fprintf(stderr,
+			"Failed to open mounts file: %s\n", strerror(errno));
+		return NULL;
+	}
+
+	while (fscanf(fp, "%*s %4095s %127s %*s %*d %*d\n",
+		      path, fstype) == 2) {
+		if (strcmp(fstype, fs_to_find) == 0) {
+			mnt = strdup(path);
+			break;
+		}
+	}
+
+	fclose(fp);
+
+	return mnt;
+}
+
+/* caller needs to free string returned */
+char *find_cgroup2_mount(bool do_mount)
+{
+	char *mnt = find_fs_mount(CGROUP2_FS_NAME);
+
+	if (mnt)
+		return mnt;
+
+	if (!do_mount) {
+		fprintf(stderr, "Failed to find cgroup2 mount\n");
+		return NULL;
+	}
+
+	mnt = strdup(MNT_CGRP2_PATH);
+	if (!mnt) {
+		fprintf(stderr, "Failed to allocate memory for cgroup2 path\n");
+		return NULL;
+
+	}
+
+	if (make_path(mnt, 0755)) {
+		fprintf(stderr, "Failed to setup cgroup2 directory\n");
+		free(mnt);
+		return NULL;
+	}
+
+	if (mount("none", mnt, CGROUP2_FS_NAME, 0, NULL)) {
+		/* EBUSY means already mounted */
+		if (errno == EBUSY)
+			goto out;
+
+		if (errno == ENODEV) {
+			fprintf(stderr,
+				"Failed to mount cgroup2. Are CGROUPS enabled in your kernel?\n");
+		} else {
+			fprintf(stderr,
+				"Failed to mount cgroup2: %s\n",
+				strerror(errno));
+		}
+		free(mnt);
+		return NULL;
+	}
+out:
+	return mnt;
+}
+
+__u64 get_cgroup2_id(const char *path)
+{
+	char fh_buf[sizeof(struct file_handle) + sizeof(__u64)] = { 0 };
+	struct file_handle *fhp = (struct file_handle *)fh_buf;
+	union {
+		__u64 id;
+		unsigned char bytes[sizeof(__u64)];
+	} cg_id = { .id = 0 };
+	char *mnt = NULL;
+	int mnt_fd = -1;
+	int mnt_id;
+
+	if (!path) {
+		fprintf(stderr, "Invalid cgroup2 path\n");
+		return 0;
+	}
+
+	fhp->handle_bytes = sizeof(__u64);
+	if (name_to_handle_at(AT_FDCWD, path, fhp, &mnt_id, 0) < 0) {
+		/* try at cgroup2 mount */
+
+		while (*path == '/')
+			path++;
+		if (*path == '\0') {
+			fprintf(stderr, "Invalid cgroup2 path\n");
+			goto out;
+		}
+
+		mnt = find_cgroup2_mount(false);
+		if (!mnt)
+			goto out;
+
+		mnt_fd = open(mnt, O_RDONLY);
+		if (mnt_fd < 0) {
+			fprintf(stderr, "Failed to open cgroup2 mount\n");
+			goto out;
+		}
+
+		fhp->handle_bytes = sizeof(__u64);
+		if (name_to_handle_at(mnt_fd, path, fhp, &mnt_id, 0) < 0) {
+			fprintf(stderr, "Failed to get cgroup2 ID: %s\n",
+					strerror(errno));
+			goto out;
+		}
+	}
+	if (fhp->handle_bytes != sizeof(__u64)) {
+		fprintf(stderr, "Invalid size of cgroup2 ID\n");
+		goto out;
+	}
+
+	memcpy(cg_id.bytes, fhp->f_handle, sizeof(__u64));
+
+out:
+	if (mnt_fd >= 0)
+		close(mnt_fd);
+	free(mnt);
+
+	return cg_id.id;
+}
+
+#define FILEID_INO32_GEN 1
+
+/* caller needs to free string returned */
+char *get_cgroup2_path(__u64 id, bool full)
+{
+	char fh_buf[sizeof(struct file_handle) + sizeof(__u64)] = { 0 };
+	struct file_handle *fhp = (struct file_handle *)fh_buf;
+	union {
+		__u64 id;
+		unsigned char bytes[sizeof(__u64)];
+	} cg_id = { .id = id };
+	int mnt_fd = -1, fd = -1;
+	char link_buf[PATH_MAX];
+	char *path = NULL;
+	char fd_path[64];
+	int link_len;
+	char *mnt = NULL;
+
+	if (!id) {
+		fprintf(stderr, "Invalid cgroup2 ID\n");
+		goto out;
+	}
+
+	mnt = find_cgroup2_mount(false);
+	if (!mnt)
+		goto out;
+
+	mnt_fd = open(mnt, O_RDONLY);
+	if (mnt_fd < 0) {
+		fprintf(stderr, "Failed to open cgroup2 mount\n");
+		goto out;
+	}
+
+	fhp->handle_bytes = sizeof(__u64);
+	fhp->handle_type = FILEID_INO32_GEN;
+	memcpy(fhp->f_handle, cg_id.bytes, sizeof(__u64));
+
+	fd = open_by_handle_at(mnt_fd, fhp, 0);
+	if (fd < 0) {
+		fprintf(stderr, "Failed to open cgroup2 by ID\n");
+		goto out;
+	}
+
+	snprintf(fd_path, sizeof(fd_path), "/proc/self/fd/%d", fd);
+	link_len = readlink(fd_path, link_buf, sizeof(link_buf) - 1);
+	if (link_len < 0) {
+		fprintf(stderr,
+			"Failed to read value of symbolic link %s\n",
+			fd_path);
+		goto out;
+	}
+	link_buf[link_len] = '\0';
+
+	if (full)
+		path = strdup(link_buf);
+	else
+		path = strdup(link_buf + strlen(mnt));
+	if (!path)
+		fprintf(stderr,
+			"Failed to allocate memory for cgroup2 path\n");
+
+out:
+	if (fd >= 0)
+		close(fd);
+	if (mnt_fd >= 0)
+		close(mnt_fd);
+	free(mnt);
+
+	return path;
+}
+
+int make_path(const char *path, mode_t mode)
+{
+	char *dir, *delim;
+	int rc = -1;
+
+	delim = dir = strdup(path);
+	if (dir == NULL) {
+		fprintf(stderr, "strdup failed copying path");
+		return -1;
+	}
+
+	/* skip '/' -- it had better exist */
+	if (*delim == '/')
+		delim++;
+
+	while (1) {
+		delim = strchr(delim, '/');
+		if (delim)
+			*delim = '\0';
+
+		rc = mkdir(dir, mode);
+		if (rc && errno != EEXIST) {
+			fprintf(stderr, "mkdir failed for %s: %s\n",
+				dir, strerror(errno));
+			goto out;
+		}
+
+		if (delim == NULL)
+			break;
+
+		*delim = '/';
+		delim++;
+		if (*delim == '\0')
+			break;
+	}
+	rc = 0;
+out:
+	free(dir);
+
+	return rc;
+}
+
+int get_command_name(const char *pid, char *comm, size_t len)
+{
+	char path[PATH_MAX];
+	char line[128];
+	FILE *fp;
+
+	if (snprintf(path, sizeof(path),
+		     "/proc/%s/status", pid) >= sizeof(path)) {
+		return -1;
+	}
+
+	fp = fopen(path, "r");
+	if (!fp)
+		return -1;
+
+	comm[0] = '\0';
+	while (fgets(line, sizeof(line), fp)) {
+		char *nl, *name;
+
+		name = strstr(line, "Name:");
+		if (!name)
+			continue;
+
+		name += 5;
+		while (isspace(*name))
+			name++;
+
+		nl = strchr(name, '\n');
+		if (nl)
+			*nl = '\0';
+
+		strlcpy(comm, name, len);
+		break;
+	}
+
+	fclose(fp);
+
+	return 0;
+}
+
+int get_task_name(pid_t pid, char *name, size_t len)
+{
+	char path[PATH_MAX];
+	FILE *f;
+
+	if (!pid)
+		return -1;
+
+	if (snprintf(path, sizeof(path), "/proc/%d/comm", pid) >= sizeof(path))
+		return -1;
+
+	f = fopen(path, "r");
+	if (!f)
+		return -1;
+
+	if (!fgets(name, len, f))
+		return -1;
+
+	/* comm ends in \n, get rid of it */
+	name[strcspn(name, "\n")] = '\0';
+
+	fclose(f);
+
+	return 0;
+}
diff --git a/lib/inet_proto.c b/lib/inet_proto.c
new file mode 100644
index 0000000..41e2e8b
--- /dev/null
+++ b/lib/inet_proto.c
@@ -0,0 +1,69 @@
+/*
+ * inet_proto.c
+ *
+ *		This program is free software; you can redistribute it and/or
+ *		modify it under the terms of the GNU General Public License
+ *		as published by the Free Software Foundation; either version
+ *		2 of the License, or (at your option) any later version.
+ *
+ * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <netdb.h>
+#include <string.h>
+
+#include "rt_names.h"
+#include "utils.h"
+
+const char *inet_proto_n2a(int proto, char *buf, int len)
+{
+	static char *ncache;
+	static int icache = -1;
+	struct protoent *pe;
+
+	if (proto == icache)
+		return ncache;
+
+	pe = getprotobynumber(proto);
+	if (pe && !numeric) {
+		if (icache != -1)
+			free(ncache);
+		icache = proto;
+		ncache = strdup(pe->p_name);
+		strlcpy(buf, pe->p_name, len);
+		return buf;
+	}
+	snprintf(buf, len, "ipproto-%d", proto);
+	return buf;
+}
+
+int inet_proto_a2n(const char *buf)
+{
+	static char *ncache;
+	static int icache = -1;
+	struct protoent *pe;
+	__u8 ret;
+
+	if (icache != -1 && strcmp(ncache, buf) == 0)
+		return icache;
+
+	if (!get_u8(&ret, buf, 10))
+		return ret;
+
+	pe = getprotobyname(buf);
+	if (pe) {
+		if (icache != -1)
+			free(ncache);
+		icache = pe->p_proto;
+		ncache = strdup(pe->p_name);
+		return pe->p_proto;
+	}
+	return -1;
+}
diff --git a/lib/json_print.c b/lib/json_print.c
new file mode 100644
index 0000000..741acdc
--- /dev/null
+++ b/lib/json_print.c
@@ -0,0 +1,361 @@
+/*
+ * json_print.c		"print regular or json output, based on json_writer".
+ *
+ *             This program is free software; you can redistribute it and/or
+ *             modify it under the terms of the GNU General Public License
+ *             as published by the Free Software Foundation; either version
+ *             2 of the License, or (at your option) any later version.
+ *
+ * Authors:    Julien Fortin, <julien@cumulusnetworks.com>
+ */
+
+#include <stdarg.h>
+#include <stdio.h>
+
+#include "utils.h"
+#include "json_print.h"
+
+static json_writer_t *_jw;
+
+static void __new_json_obj(int json, bool have_array)
+{
+	if (json) {
+		_jw = jsonw_new(stdout);
+		if (!_jw) {
+			perror("json object");
+			exit(1);
+		}
+		if (pretty)
+			jsonw_pretty(_jw, true);
+		if (have_array)
+			jsonw_start_array(_jw);
+	}
+}
+
+static void __delete_json_obj(bool have_array)
+{
+	if (_jw) {
+		if (have_array)
+			jsonw_end_array(_jw);
+		jsonw_destroy(&_jw);
+	}
+}
+
+void new_json_obj(int json)
+{
+	__new_json_obj(json, true);
+}
+
+void delete_json_obj(void)
+{
+	__delete_json_obj(true);
+}
+
+void new_json_obj_plain(int json)
+{
+	__new_json_obj(json, false);
+}
+
+void delete_json_obj_plain(void)
+{
+	__delete_json_obj(false);
+}
+
+bool is_json_context(void)
+{
+	return _jw != NULL;
+}
+
+json_writer_t *get_json_writer(void)
+{
+	return _jw;
+}
+
+void open_json_object(const char *str)
+{
+	if (_IS_JSON_CONTEXT(PRINT_JSON)) {
+		if (str)
+			jsonw_name(_jw, str);
+		jsonw_start_object(_jw);
+	}
+}
+
+void close_json_object(void)
+{
+	if (_IS_JSON_CONTEXT(PRINT_JSON))
+		jsonw_end_object(_jw);
+}
+
+/*
+ * Start json array or string array using
+ * the provided string as json key (if not null)
+ * or as array delimiter in non-json context.
+ */
+void open_json_array(enum output_type type, const char *str)
+{
+	if (_IS_JSON_CONTEXT(type)) {
+		if (str)
+			jsonw_name(_jw, str);
+		jsonw_start_array(_jw);
+	} else if (_IS_FP_CONTEXT(type)) {
+		printf("%s", str);
+	}
+}
+
+/*
+ * End json array or string array
+ */
+void close_json_array(enum output_type type, const char *str)
+{
+	if (_IS_JSON_CONTEXT(type)) {
+		jsonw_end_array(_jw);
+	} else if (_IS_FP_CONTEXT(type)) {
+		printf("%s", str);
+	}
+}
+
+/*
+ * pre-processor directive to generate similar
+ * functions handling different types
+ */
+#define _PRINT_FUNC(type_name, type)					\
+	__attribute__((format(printf, 4, 0)))				\
+	int print_color_##type_name(enum output_type t,			\
+				    enum color_attr color,		\
+				    const char *key,			\
+				    const char *fmt,			\
+				    type value)				\
+	{								\
+		int ret = 0;						\
+		if (_IS_JSON_CONTEXT(t)) {				\
+			if (!key)					\
+				jsonw_##type_name(_jw, value);		\
+			else						\
+				jsonw_##type_name##_field(_jw, key, value); \
+		} else if (_IS_FP_CONTEXT(t)) {				\
+			ret = color_fprintf(stdout, color, fmt, value); \
+		}							\
+		return ret;						\
+	}
+_PRINT_FUNC(int, int);
+_PRINT_FUNC(s64, int64_t);
+_PRINT_FUNC(hhu, unsigned char);
+_PRINT_FUNC(hu, unsigned short);
+_PRINT_FUNC(uint, unsigned int);
+_PRINT_FUNC(u64, uint64_t);
+_PRINT_FUNC(luint, unsigned long);
+_PRINT_FUNC(lluint, unsigned long long);
+_PRINT_FUNC(float, double);
+#undef _PRINT_FUNC
+
+#define _PRINT_NAME_VALUE_FUNC(type_name, type, format_char)		 \
+	void print_##type_name##_name_value(const char *name, type value)\
+	{								 \
+		SPRINT_BUF(format);					 \
+									 \
+		snprintf(format, SPRINT_BSIZE,				 \
+			 "%s %%"#format_char, name);			 \
+		print_##type_name(PRINT_ANY, name, format, value);	 \
+	}
+_PRINT_NAME_VALUE_FUNC(uint, unsigned int, u);
+_PRINT_NAME_VALUE_FUNC(string, const char*, s);
+#undef _PRINT_NAME_VALUE_FUNC
+
+int print_color_string(enum output_type type,
+		       enum color_attr color,
+		       const char *key,
+		       const char *fmt,
+		       const char *value)
+{
+	int ret = 0;
+
+	if (_IS_JSON_CONTEXT(type)) {
+		if (key && !value)
+			jsonw_name(_jw, key);
+		else if (!key && value)
+			jsonw_string(_jw, value);
+		else
+			jsonw_string_field(_jw, key, value);
+	} else if (_IS_FP_CONTEXT(type)) {
+		ret = color_fprintf(stdout, color, fmt, value);
+	}
+
+	return ret;
+}
+
+/*
+ * value's type is bool. When using this function in FP context you can't pass
+ * a value to it, you will need to use "is_json_context()" to have different
+ * branch for json and regular output. grep -r "print_bool" for example
+ */
+static int __print_color_bool(enum output_type type,
+			      enum color_attr color,
+			      const char *key,
+			      const char *fmt,
+			      bool value,
+			      const char *str)
+{
+	int ret = 0;
+
+	if (_IS_JSON_CONTEXT(type)) {
+		if (key)
+			jsonw_bool_field(_jw, key, value);
+		else
+			jsonw_bool(_jw, value);
+	} else if (_IS_FP_CONTEXT(type)) {
+		ret = color_fprintf(stdout, color, fmt, str);
+	}
+
+	return ret;
+}
+
+int print_color_bool(enum output_type type,
+		     enum color_attr color,
+		     const char *key,
+		     const char *fmt,
+		     bool value)
+{
+	return __print_color_bool(type, color, key, fmt, value,
+				  value ? "true" : "false");
+}
+
+int print_color_on_off(enum output_type type,
+		       enum color_attr color,
+		       const char *key,
+		       const char *fmt,
+		       bool value)
+{
+	return __print_color_bool(type, color, key, fmt, value,
+				  value ? "on" : "off");
+}
+
+/*
+ * In JSON context uses hardcode %#x format: 42 -> 0x2a
+ */
+int print_color_0xhex(enum output_type type,
+		      enum color_attr color,
+		      const char *key,
+		      const char *fmt,
+		      unsigned long long hex)
+{
+	int ret = 0;
+
+	if (_IS_JSON_CONTEXT(type)) {
+		SPRINT_BUF(b1);
+
+		snprintf(b1, sizeof(b1), "%#llx", hex);
+		print_string(PRINT_JSON, key, NULL, b1);
+	} else if (_IS_FP_CONTEXT(type)) {
+		ret = color_fprintf(stdout, color, fmt, hex);
+	}
+
+	return ret;
+}
+
+int print_color_hex(enum output_type type,
+		    enum color_attr color,
+		    const char *key,
+		    const char *fmt,
+		    unsigned int hex)
+{
+	int ret = 0;
+
+	if (_IS_JSON_CONTEXT(type)) {
+		SPRINT_BUF(b1);
+
+		snprintf(b1, sizeof(b1), "%x", hex);
+		if (key)
+			jsonw_string_field(_jw, key, b1);
+		else
+			jsonw_string(_jw, b1);
+	} else if (_IS_FP_CONTEXT(type)) {
+		ret = color_fprintf(stdout, color, fmt, hex);
+	}
+
+	return ret;
+}
+
+/*
+ * In JSON context we don't use the argument "value" we simply call jsonw_null
+ * whereas FP context can use "value" to output anything
+ */
+int print_color_null(enum output_type type,
+		     enum color_attr color,
+		     const char *key,
+		     const char *fmt,
+		     const char *value)
+{
+	int ret = 0;
+
+	if (_IS_JSON_CONTEXT(type)) {
+		if (key)
+			jsonw_null_field(_jw, key);
+		else
+			jsonw_null(_jw);
+	} else if (_IS_FP_CONTEXT(type)) {
+		ret = color_fprintf(stdout, color, fmt, value);
+	}
+
+	return ret;
+}
+
+/*
+ * This function does take printf style argument but applying
+ * format attribute to causes more warnings since the print_XXX
+ * functions are used with NULL for format if unused.
+ */
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wformat-nonliteral"
+int print_color_tv(enum output_type type,
+		   enum color_attr color,
+		   const char *key,
+		   const char *fmt,
+		   const struct timeval *tv)
+{
+	double usecs = tv->tv_usec;
+	double secs = tv->tv_sec;
+	double time = secs + usecs / 1000000;
+
+	return print_color_float(type, color, key, fmt, time);
+}
+#pragma GCC diagnostic pop
+
+/* Print line separator (if not in JSON mode) */
+void print_nl(void)
+{
+	if (!_jw)
+		printf("%s", _SL_);
+}
+
+int print_color_rate(bool use_iec, enum output_type type, enum color_attr color,
+		     const char *key, const char *fmt, unsigned long long rate)
+{
+	unsigned long kilo = use_iec ? 1024 : 1000;
+	const char *str = use_iec ? "i" : "";
+	static char *units[5] = {"", "K", "M", "G", "T"};
+	char *buf;
+	int rc;
+	int i;
+
+	if (_IS_JSON_CONTEXT(type))
+		return print_color_lluint(type, color, key, "%llu", rate);
+
+	rate <<= 3; /* bytes/sec -> bits/sec */
+
+	for (i = 0; i < ARRAY_SIZE(units) - 1; i++)  {
+		if (rate < kilo)
+			break;
+		if (((rate % kilo) != 0) && rate < 1000*kilo)
+			break;
+		rate /= kilo;
+	}
+
+	rc = asprintf(&buf, "%.0f%s%sbit", (double)rate, units[i],
+		      i > 0 ? str : "");
+	if (rc < 0)
+		return -1;
+
+	rc = print_color_string(type, color, key, fmt, buf);
+	free(buf);
+	return rc;
+}
diff --git a/lib/json_print_math.c b/lib/json_print_math.c
new file mode 100644
index 0000000..f4d5049
--- /dev/null
+++ b/lib/json_print_math.c
@@ -0,0 +1,37 @@
+// SPDX-License-Identifier: GPL-2.0+
+
+#include <stdarg.h>
+#include <stdio.h>
+#include <math.h>
+
+#include "utils.h"
+#include "json_print.h"
+
+char *sprint_size(__u32 sz, char *buf)
+{
+	long kilo = 1024;
+	long mega = kilo * kilo;
+	size_t len = SPRINT_BSIZE - 1;
+	double tmp = sz;
+
+	if (sz >= mega && fabs(mega * rint(tmp / mega) - sz) < 1024)
+		snprintf(buf, len, "%gMb", rint(tmp / mega));
+	else if (sz >= kilo && fabs(kilo * rint(tmp / kilo) - sz) < 16)
+		snprintf(buf, len, "%gKb", rint(tmp / kilo));
+	else
+		snprintf(buf, len, "%ub", sz);
+
+	return buf;
+}
+
+int print_color_size(enum output_type type, enum color_attr color,
+		     const char *key, const char *fmt, __u32 sz)
+{
+	SPRINT_BUF(buf);
+
+	if (_IS_JSON_CONTEXT(type))
+		return print_color_uint(type, color, key, "%u", sz);
+
+	sprint_size(sz, buf);
+	return print_color_string(type, color, key, fmt, buf);
+}
diff --git a/lib/json_writer.c b/lib/json_writer.c
new file mode 100644
index 0000000..2f3936c
--- /dev/null
+++ b/lib/json_writer.c
@@ -0,0 +1,386 @@
+/* SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) */
+/*
+ * Simple streaming JSON writer
+ *
+ * This takes care of the annoying bits of JSON syntax like the commas
+ * after elements
+ *
+ * Authors:	Stephen Hemminger <stephen@networkplumber.org>
+ */
+
+#include <stdio.h>
+#include <stdbool.h>
+#include <stdarg.h>
+#include <assert.h>
+#include <malloc.h>
+#include <inttypes.h>
+#include <stdint.h>
+
+#include "json_writer.h"
+
+struct json_writer {
+	FILE		*out;	/* output file */
+	unsigned	depth;  /* nesting */
+	bool		pretty; /* optional whitepace */
+	char		sep;	/* either nul or comma */
+};
+
+/* indentation for pretty print */
+static void jsonw_indent(json_writer_t *self)
+{
+	unsigned i;
+	for (i = 0; i < self->depth; ++i)
+		fputs("    ", self->out);
+}
+
+/* end current line and indent if pretty printing */
+static void jsonw_eol(json_writer_t *self)
+{
+	if (!self->pretty)
+		return;
+
+	putc('\n', self->out);
+	jsonw_indent(self);
+}
+
+/* If current object is not empty print a comma */
+static void jsonw_eor(json_writer_t *self)
+{
+	if (self->sep != '\0')
+		putc(self->sep, self->out);
+	self->sep = ',';
+}
+
+
+/* Output JSON encoded string */
+/* Handles C escapes, does not do Unicode */
+static void jsonw_puts(json_writer_t *self, const char *str)
+{
+	putc('"', self->out);
+	for (; *str; ++str)
+		switch (*str) {
+		case '\t':
+			fputs("\\t", self->out);
+			break;
+		case '\n':
+			fputs("\\n", self->out);
+			break;
+		case '\r':
+			fputs("\\r", self->out);
+			break;
+		case '\f':
+			fputs("\\f", self->out);
+			break;
+		case '\b':
+			fputs("\\b", self->out);
+			break;
+		case '\\':
+			fputs("\\\\", self->out);
+			break;
+		case '"':
+			fputs("\\\"", self->out);
+			break;
+		default:
+			putc(*str, self->out);
+		}
+	putc('"', self->out);
+}
+
+/* Create a new JSON stream */
+json_writer_t *jsonw_new(FILE *f)
+{
+	json_writer_t *self = malloc(sizeof(*self));
+	if (self) {
+		self->out = f;
+		self->depth = 0;
+		self->pretty = false;
+		self->sep = '\0';
+	}
+	return self;
+}
+
+/* End output to JSON stream */
+void jsonw_destroy(json_writer_t **self_p)
+{
+	json_writer_t *self = *self_p;
+
+	assert(self->depth == 0);
+	fputs("\n", self->out);
+	fflush(self->out);
+	free(self);
+	*self_p = NULL;
+}
+
+void jsonw_pretty(json_writer_t *self, bool on)
+{
+	self->pretty = on;
+}
+
+/* Basic blocks */
+static void jsonw_begin(json_writer_t *self, int c)
+{
+	jsonw_eor(self);
+	putc(c, self->out);
+	++self->depth;
+	self->sep = '\0';
+}
+
+static void jsonw_end(json_writer_t *self, int c)
+{
+	assert(self->depth > 0);
+
+	--self->depth;
+	if (self->sep != '\0')
+		jsonw_eol(self);
+	putc(c, self->out);
+	self->sep = ',';
+}
+
+
+/* Add a JSON property name */
+void jsonw_name(json_writer_t *self, const char *name)
+{
+	jsonw_eor(self);
+	jsonw_eol(self);
+	self->sep = '\0';
+	jsonw_puts(self, name);
+	putc(':', self->out);
+	if (self->pretty)
+		putc(' ', self->out);
+}
+
+__attribute__((format(printf, 2, 3)))
+void jsonw_printf(json_writer_t *self, const char *fmt, ...)
+{
+	va_list ap;
+
+	va_start(ap, fmt);
+	jsonw_eor(self);
+	vfprintf(self->out, fmt, ap);
+	va_end(ap);
+}
+
+/* Collections */
+void jsonw_start_object(json_writer_t *self)
+{
+	jsonw_begin(self, '{');
+}
+
+void jsonw_end_object(json_writer_t *self)
+{
+	jsonw_end(self, '}');
+}
+
+void jsonw_start_array(json_writer_t *self)
+{
+	jsonw_begin(self, '[');
+	if (self->pretty)
+		putc(' ', self->out);
+}
+
+void jsonw_end_array(json_writer_t *self)
+{
+	if (self->pretty && self->sep)
+		putc(' ', self->out);
+	self->sep = '\0';
+	jsonw_end(self, ']');
+}
+
+/* JSON value types */
+void jsonw_string(json_writer_t *self, const char *value)
+{
+	jsonw_eor(self);
+	jsonw_puts(self, value);
+}
+
+void jsonw_bool(json_writer_t *self, bool val)
+{
+	jsonw_printf(self, "%s", val ? "true" : "false");
+}
+
+void jsonw_null(json_writer_t *self)
+{
+	jsonw_printf(self, "null");
+}
+
+void jsonw_float(json_writer_t *self, double num)
+{
+	jsonw_printf(self, "%g", num);
+}
+
+void jsonw_hhu(json_writer_t *self, unsigned char num)
+{
+	jsonw_printf(self, "%hhu", num);
+}
+
+void jsonw_hu(json_writer_t *self, unsigned short num)
+{
+	jsonw_printf(self, "%hu", num);
+}
+
+void jsonw_uint(json_writer_t *self, unsigned int num)
+{
+	jsonw_printf(self, "%u", num);
+}
+
+void jsonw_u64(json_writer_t *self, uint64_t num)
+{
+	jsonw_printf(self, "%"PRIu64, num);
+}
+
+void jsonw_xint(json_writer_t *self, uint64_t num)
+{
+	jsonw_printf(self, "%"PRIx64, num);
+}
+
+void jsonw_luint(json_writer_t *self, unsigned long num)
+{
+	jsonw_printf(self, "%lu", num);
+}
+
+void jsonw_lluint(json_writer_t *self, unsigned long long num)
+{
+	jsonw_printf(self, "%llu", num);
+}
+
+void jsonw_int(json_writer_t *self, int num)
+{
+	jsonw_printf(self, "%d", num);
+}
+
+void jsonw_s64(json_writer_t *self, int64_t num)
+{
+	jsonw_printf(self, "%"PRId64, num);
+}
+
+/* Basic name/value objects */
+void jsonw_string_field(json_writer_t *self, const char *prop, const char *val)
+{
+	jsonw_name(self, prop);
+	jsonw_string(self, val);
+}
+
+void jsonw_bool_field(json_writer_t *self, const char *prop, bool val)
+{
+	jsonw_name(self, prop);
+	jsonw_bool(self, val);
+}
+
+void jsonw_float_field(json_writer_t *self, const char *prop, double val)
+{
+	jsonw_name(self, prop);
+	jsonw_float(self, val);
+}
+
+void jsonw_uint_field(json_writer_t *self, const char *prop, unsigned int num)
+{
+	jsonw_name(self, prop);
+	jsonw_uint(self, num);
+}
+
+void jsonw_u64_field(json_writer_t *self, const char *prop, uint64_t num)
+{
+	jsonw_name(self, prop);
+	jsonw_u64(self, num);
+}
+
+void jsonw_xint_field(json_writer_t *self, const char *prop, uint64_t num)
+{
+	jsonw_name(self, prop);
+	jsonw_xint(self, num);
+}
+
+void jsonw_hhu_field(json_writer_t *self, const char *prop, unsigned char num)
+{
+	jsonw_name(self, prop);
+	jsonw_hhu(self, num);
+}
+
+void jsonw_hu_field(json_writer_t *self, const char *prop, unsigned short num)
+{
+	jsonw_name(self, prop);
+	jsonw_hu(self, num);
+}
+
+void jsonw_luint_field(json_writer_t *self,
+			const char *prop,
+			unsigned long num)
+{
+	jsonw_name(self, prop);
+	jsonw_luint(self, num);
+}
+
+void jsonw_lluint_field(json_writer_t *self,
+			const char *prop,
+			unsigned long long num)
+{
+	jsonw_name(self, prop);
+	jsonw_lluint(self, num);
+}
+
+void jsonw_int_field(json_writer_t *self, const char *prop, int num)
+{
+	jsonw_name(self, prop);
+	jsonw_int(self, num);
+}
+
+void jsonw_s64_field(json_writer_t *self, const char *prop, int64_t num)
+{
+	jsonw_name(self, prop);
+	jsonw_s64(self, num);
+}
+
+void jsonw_null_field(json_writer_t *self, const char *prop)
+{
+	jsonw_name(self, prop);
+	jsonw_null(self);
+}
+
+#ifdef TEST
+int main(int argc, char **argv)
+{
+	json_writer_t *wr = jsonw_new(stdout);
+
+	jsonw_start_object(wr);
+	jsonw_pretty(wr, true);
+	jsonw_name(wr, "Vyatta");
+	jsonw_start_object(wr);
+	jsonw_string_field(wr, "url", "http://vyatta.com");
+	jsonw_uint_field(wr, "downloads", 2000000ul);
+	jsonw_float_field(wr, "stock", 8.16);
+
+	jsonw_name(wr, "ARGV");
+	jsonw_start_array(wr);
+	while (--argc)
+		jsonw_string(wr, *++argv);
+	jsonw_end_array(wr);
+
+	jsonw_name(wr, "empty");
+	jsonw_start_array(wr);
+	jsonw_end_array(wr);
+
+	jsonw_name(wr, "NIL");
+	jsonw_start_object(wr);
+	jsonw_end_object(wr);
+
+	jsonw_null_field(wr, "my_null");
+
+	jsonw_name(wr, "special chars");
+	jsonw_start_array(wr);
+	jsonw_string_field(wr, "slash", "/");
+	jsonw_string_field(wr, "newline", "\n");
+	jsonw_string_field(wr, "tab", "\t");
+	jsonw_string_field(wr, "ff", "\f");
+	jsonw_string_field(wr, "quote", "\"");
+	jsonw_string_field(wr, "tick", "\'");
+	jsonw_string_field(wr, "backslash", "\\");
+	jsonw_end_array(wr);
+
+	jsonw_end_object(wr);
+
+	jsonw_end_object(wr);
+	jsonw_destroy(&wr);
+	return 0;
+}
+
+#endif
diff --git a/lib/libgenl.c b/lib/libgenl.c
new file mode 100644
index 0000000..fca07f9
--- /dev/null
+++ b/lib/libgenl.c
@@ -0,0 +1,159 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * libgenl.c	GENL library
+ */
+
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include <linux/genetlink.h>
+#include "libgenl.h"
+
+static int genl_parse_getfamily(struct nlmsghdr *nlh)
+{
+	struct rtattr *tb[CTRL_ATTR_MAX + 1];
+	struct genlmsghdr *ghdr = NLMSG_DATA(nlh);
+	int len = nlh->nlmsg_len;
+	struct rtattr *attrs;
+
+	if (nlh->nlmsg_type != GENL_ID_CTRL) {
+		fprintf(stderr, "Not a controller message, nlmsg_len=%d "
+			"nlmsg_type=0x%x\n", nlh->nlmsg_len, nlh->nlmsg_type);
+		return -1;
+	}
+
+	len -= NLMSG_LENGTH(GENL_HDRLEN);
+
+	if (len < 0) {
+		fprintf(stderr, "wrong controller message len %d\n", len);
+		return -1;
+	}
+
+	if (ghdr->cmd != CTRL_CMD_NEWFAMILY) {
+		fprintf(stderr, "Unknown controller command %d\n", ghdr->cmd);
+		return -1;
+	}
+
+	attrs = (struct rtattr *) ((char *) ghdr + GENL_HDRLEN);
+	parse_rtattr(tb, CTRL_ATTR_MAX, attrs, len);
+
+	if (tb[CTRL_ATTR_FAMILY_ID] == NULL) {
+		fprintf(stderr, "Missing family id TLV\n");
+		return -1;
+	}
+
+	return rta_getattr_u16(tb[CTRL_ATTR_FAMILY_ID]);
+}
+
+int genl_resolve_family(struct rtnl_handle *grth, const char *family)
+{
+	GENL_REQUEST(req, 1024, GENL_ID_CTRL, 0, 0, CTRL_CMD_GETFAMILY,
+		     NLM_F_REQUEST);
+	struct nlmsghdr *answer;
+	int fnum;
+
+	addattr_l(&req.n, sizeof(req), CTRL_ATTR_FAMILY_NAME,
+		  family, strlen(family) + 1);
+
+	if (rtnl_talk(grth, &req.n, &answer) < 0) {
+		fprintf(stderr, "Error talking to the kernel\n");
+		return -2;
+	}
+
+	fnum = genl_parse_getfamily(answer);
+	free(answer);
+
+	return fnum;
+}
+
+static int genl_parse_grps(struct rtattr *attr, const char *name, unsigned int *id)
+{
+	const struct rtattr *pos;
+
+	rtattr_for_each_nested(pos, attr) {
+		struct rtattr *tb[CTRL_ATTR_MCAST_GRP_MAX + 1];
+
+		parse_rtattr_nested(tb, CTRL_ATTR_MCAST_GRP_MAX, pos);
+
+		if (tb[CTRL_ATTR_MCAST_GRP_NAME] && tb[CTRL_ATTR_MCAST_GRP_ID]) {
+			if (strcmp(name, rta_getattr_str(tb[CTRL_ATTR_MCAST_GRP_NAME])) == 0) {
+				*id = rta_getattr_u32(tb[CTRL_ATTR_MCAST_GRP_ID]);
+				return 0;
+			}
+		}
+	}
+
+	errno = ENOENT;
+	return -1;
+}
+
+int genl_add_mcast_grp(struct rtnl_handle *grth, __u16 fnum, const char *group)
+{
+	GENL_REQUEST(req, 1024, GENL_ID_CTRL, 0, 0, CTRL_CMD_GETFAMILY,
+		     NLM_F_REQUEST);
+	struct rtattr *tb[CTRL_ATTR_MAX + 1];
+	struct nlmsghdr *answer = NULL;
+	struct genlmsghdr *ghdr;
+	struct rtattr *attrs;
+	int len, ret = -1;
+	unsigned int id;
+
+	addattr16(&req.n, sizeof(req), CTRL_ATTR_FAMILY_ID, fnum);
+
+	if (rtnl_talk(grth, &req.n, &answer) < 0) {
+		fprintf(stderr, "Error talking to the kernel\n");
+		return -2;
+	}
+
+	ghdr = NLMSG_DATA(answer);
+	len = answer->nlmsg_len;
+
+	if (answer->nlmsg_type != GENL_ID_CTRL) {
+		errno = EINVAL;
+		goto err_free;
+	}
+
+	len -= NLMSG_LENGTH(GENL_HDRLEN);
+	if (len < 0) {
+		errno = EINVAL;
+		goto err_free;
+	}
+
+	attrs = (struct rtattr *) ((char *) ghdr + GENL_HDRLEN);
+	parse_rtattr(tb, CTRL_ATTR_MAX, attrs, len);
+
+	if (tb[CTRL_ATTR_MCAST_GROUPS] == NULL) {
+		errno = ENOENT;
+		fprintf(stderr, "Missing mcast groups TLV\n");
+		goto err_free;
+	}
+
+	if (genl_parse_grps(tb[CTRL_ATTR_MCAST_GROUPS], group, &id) < 0)
+		goto err_free;
+
+	ret = rtnl_add_nl_group(grth, id);
+
+err_free:
+	free(answer);
+	return ret;
+}
+
+int genl_init_handle(struct rtnl_handle *grth, const char *family,
+		     int *genl_family)
+{
+	if (*genl_family >= 0)
+		return 0;
+
+	if (rtnl_open_byproto(grth, 0, NETLINK_GENERIC) < 0) {
+		fprintf(stderr, "Cannot open generic netlink socket\n");
+		return -1;
+	}
+
+	*genl_family = genl_resolve_family(grth, family);
+	if (*genl_family < 0)
+		return -1;
+
+	return 0;
+}
diff --git a/lib/libnetlink.c b/lib/libnetlink.c
new file mode 100644
index 0000000..001efc1
--- /dev/null
+++ b/lib/libnetlink.c
@@ -0,0 +1,1657 @@
+/*
+ * libnetlink.c	RTnetlink service routines.
+ *
+ *		This program is free software; you can redistribute it and/or
+ *		modify it under the terms of the GNU General Public License
+ *		as published by the Free Software Foundation; either version
+ *		2 of the License, or (at your option) any later version.
+ *
+ * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdbool.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <net/if_arp.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <string.h>
+#include <errno.h>
+#include <time.h>
+#include <sys/uio.h>
+#include <linux/fib_rules.h>
+#include <linux/if_addrlabel.h>
+#include <linux/if_bridge.h>
+#include <linux/nexthop.h>
+
+#include "libnetlink.h"
+#include "utils.h"
+
+#ifndef __aligned
+#define __aligned(x)		__attribute__((aligned(x)))
+#endif
+
+#ifndef SOL_NETLINK
+#define SOL_NETLINK 270
+#endif
+
+#ifndef MIN
+#define MIN(a, b) ((a) < (b) ? (a) : (b))
+#endif
+
+int rcvbuf = 1024 * 1024;
+
+#ifdef HAVE_LIBMNL
+#include <libmnl/libmnl.h>
+
+static const enum mnl_attr_data_type extack_policy[NLMSGERR_ATTR_MAX + 1] = {
+	[NLMSGERR_ATTR_MSG]	= MNL_TYPE_NUL_STRING,
+	[NLMSGERR_ATTR_OFFS]	= MNL_TYPE_U32,
+};
+
+static int err_attr_cb(const struct nlattr *attr, void *data)
+{
+	const struct nlattr **tb = data;
+	uint16_t type;
+
+	if (mnl_attr_type_valid(attr, NLMSGERR_ATTR_MAX) < 0) {
+		fprintf(stderr, "Invalid extack attribute\n");
+		return MNL_CB_ERROR;
+	}
+
+	type = mnl_attr_get_type(attr);
+	if (mnl_attr_validate(attr, extack_policy[type]) < 0) {
+		fprintf(stderr, "extack attribute %d failed validation\n",
+			type);
+		return MNL_CB_ERROR;
+	}
+
+	tb[type] = attr;
+	return MNL_CB_OK;
+}
+
+static void print_ext_ack_msg(bool is_err, const char *msg)
+{
+	fprintf(stderr, "%s: %s", is_err ? "Error" : "Warning", msg);
+	if (msg[strlen(msg) - 1] != '.')
+		fprintf(stderr, ".");
+	fprintf(stderr, "\n");
+}
+
+/* dump netlink extended ack error message */
+int nl_dump_ext_ack(const struct nlmsghdr *nlh, nl_ext_ack_fn_t errfn)
+{
+	struct nlattr *tb[NLMSGERR_ATTR_MAX + 1] = {};
+	const struct nlmsgerr *err = mnl_nlmsg_get_payload(nlh);
+	const struct nlmsghdr *err_nlh = NULL;
+	unsigned int hlen = sizeof(*err);
+	const char *msg = NULL;
+	uint32_t off = 0;
+
+	/* no TLVs, nothing to do here */
+	if (!(nlh->nlmsg_flags & NLM_F_ACK_TLVS))
+		return 0;
+
+	/* if NLM_F_CAPPED is set then the inner err msg was capped */
+	if (!(nlh->nlmsg_flags & NLM_F_CAPPED))
+		hlen += mnl_nlmsg_get_payload_len(&err->msg);
+
+	if (mnl_attr_parse(nlh, hlen, err_attr_cb, tb) != MNL_CB_OK)
+		return 0;
+
+	if (tb[NLMSGERR_ATTR_MSG])
+		msg = mnl_attr_get_str(tb[NLMSGERR_ATTR_MSG]);
+
+	if (tb[NLMSGERR_ATTR_OFFS]) {
+		off = mnl_attr_get_u32(tb[NLMSGERR_ATTR_OFFS]);
+
+		if (off > nlh->nlmsg_len) {
+			fprintf(stderr,
+				"Invalid offset for NLMSGERR_ATTR_OFFS\n");
+			off = 0;
+		} else if (!(nlh->nlmsg_flags & NLM_F_CAPPED))
+			err_nlh = &err->msg;
+	}
+
+	if (errfn)
+		return errfn(msg, off, err_nlh);
+
+	if (msg && *msg != '\0') {
+		bool is_err = !!err->error;
+
+		print_ext_ack_msg(is_err, msg);
+		return is_err ? 1 : 0;
+	}
+
+	return 0;
+}
+
+int nl_dump_ext_ack_done(const struct nlmsghdr *nlh, unsigned int offset, int error)
+{
+	struct nlattr *tb[NLMSGERR_ATTR_MAX + 1] = {};
+	const char *msg = NULL;
+
+	if (mnl_attr_parse(nlh, offset, err_attr_cb, tb) != MNL_CB_OK)
+		return 0;
+
+	if (tb[NLMSGERR_ATTR_MSG])
+		msg = mnl_attr_get_str(tb[NLMSGERR_ATTR_MSG]);
+
+	if (msg && *msg != '\0') {
+		bool is_err = !!error;
+
+		print_ext_ack_msg(is_err, msg);
+		return is_err ? 1 : 0;
+	}
+
+	return 0;
+}
+#else
+#warning "libmnl required for error support"
+
+/* No extended error ack without libmnl */
+int nl_dump_ext_ack(const struct nlmsghdr *nlh, nl_ext_ack_fn_t errfn)
+{
+	return 0;
+}
+
+int nl_dump_ext_ack_done(const struct nlmsghdr *nlh, unsigned int offset, int error)
+{
+	return 0;
+}
+#endif
+
+/* Older kernels may not support strict dump and filtering */
+void rtnl_set_strict_dump(struct rtnl_handle *rth)
+{
+	int one = 1;
+
+	if (setsockopt(rth->fd, SOL_NETLINK, NETLINK_GET_STRICT_CHK,
+		       &one, sizeof(one)) < 0)
+		return;
+
+	rth->flags |= RTNL_HANDLE_F_STRICT_CHK;
+}
+
+int rtnl_add_nl_group(struct rtnl_handle *rth, unsigned int group)
+{
+	return setsockopt(rth->fd, SOL_NETLINK, NETLINK_ADD_MEMBERSHIP,
+			  &group, sizeof(group));
+}
+
+void rtnl_close(struct rtnl_handle *rth)
+{
+	if (rth->fd >= 0) {
+		close(rth->fd);
+		rth->fd = -1;
+	}
+}
+
+int rtnl_open_byproto(struct rtnl_handle *rth, unsigned int subscriptions,
+		      int protocol)
+{
+	socklen_t addr_len;
+	int sndbuf = 32768;
+	int one = 1;
+
+	memset(rth, 0, sizeof(*rth));
+
+	rth->proto = protocol;
+	rth->fd = socket(AF_NETLINK, SOCK_RAW | SOCK_CLOEXEC, protocol);
+	if (rth->fd < 0) {
+		perror("Cannot open netlink socket");
+		return -1;
+	}
+
+	if (setsockopt(rth->fd, SOL_SOCKET, SO_SNDBUF,
+		       &sndbuf, sizeof(sndbuf)) < 0) {
+		perror("SO_SNDBUF");
+		goto err;
+	}
+
+	if (setsockopt(rth->fd, SOL_SOCKET, SO_RCVBUF,
+		       &rcvbuf, sizeof(rcvbuf)) < 0) {
+		perror("SO_RCVBUF");
+		goto err;
+	}
+
+	/* Older kernels may no support extended ACK reporting */
+	setsockopt(rth->fd, SOL_NETLINK, NETLINK_EXT_ACK,
+		   &one, sizeof(one));
+
+	memset(&rth->local, 0, sizeof(rth->local));
+	rth->local.nl_family = AF_NETLINK;
+	rth->local.nl_groups = subscriptions;
+
+	if (bind(rth->fd, (struct sockaddr *)&rth->local,
+		 sizeof(rth->local)) < 0) {
+		perror("Cannot bind netlink socket");
+		goto err;
+	}
+	addr_len = sizeof(rth->local);
+	if (getsockname(rth->fd, (struct sockaddr *)&rth->local,
+			&addr_len) < 0) {
+		perror("Cannot getsockname");
+		goto err;
+	}
+	if (addr_len != sizeof(rth->local)) {
+		fprintf(stderr, "Wrong address length %d\n", addr_len);
+		goto err;
+	}
+	if (rth->local.nl_family != AF_NETLINK) {
+		fprintf(stderr, "Wrong address family %d\n",
+			rth->local.nl_family);
+		goto err;
+	}
+	rth->seq = time(NULL);
+	return 0;
+err:
+	rtnl_close(rth);
+	return -1;
+}
+
+int rtnl_open(struct rtnl_handle *rth, unsigned int subscriptions)
+{
+	return rtnl_open_byproto(rth, subscriptions, NETLINK_ROUTE);
+}
+
+int rtnl_nexthopdump_req(struct rtnl_handle *rth, int family,
+			 req_filter_fn_t filter_fn)
+{
+	struct {
+		struct nlmsghdr nlh;
+		struct nhmsg nhm;
+		char buf[128];
+	} req = {
+		.nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct nhmsg)),
+		.nlh.nlmsg_type = RTM_GETNEXTHOP,
+		.nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,
+		.nlh.nlmsg_seq = rth->dump = ++rth->seq,
+		.nhm.nh_family = family,
+	};
+
+	if (filter_fn) {
+		int err;
+
+		err = filter_fn(&req.nlh, sizeof(req));
+		if (err)
+			return err;
+	}
+
+	return send(rth->fd, &req, sizeof(req), 0);
+}
+
+int rtnl_nexthop_bucket_dump_req(struct rtnl_handle *rth, int family,
+				 req_filter_fn_t filter_fn)
+{
+	struct {
+		struct nlmsghdr nlh;
+		struct nhmsg nhm;
+		char buf[128];
+	} req = {
+		.nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct nhmsg)),
+		.nlh.nlmsg_type = RTM_GETNEXTHOPBUCKET,
+		.nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,
+		.nlh.nlmsg_seq = rth->dump = ++rth->seq,
+		.nhm.nh_family = family,
+	};
+
+	if (filter_fn) {
+		int err;
+
+		err = filter_fn(&req.nlh, sizeof(req));
+		if (err)
+			return err;
+	}
+
+	return send(rth->fd, &req, sizeof(req), 0);
+}
+
+int rtnl_addrdump_req(struct rtnl_handle *rth, int family,
+		      req_filter_fn_t filter_fn)
+{
+	struct {
+		struct nlmsghdr nlh;
+		struct ifaddrmsg ifm;
+		char buf[128];
+	} req = {
+		.nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifaddrmsg)),
+		.nlh.nlmsg_type = RTM_GETADDR,
+		.nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,
+		.nlh.nlmsg_seq = rth->dump = ++rth->seq,
+		.ifm.ifa_family = family,
+	};
+
+	if (filter_fn) {
+		int err;
+
+		err = filter_fn(&req.nlh, sizeof(req));
+		if (err)
+			return err;
+	}
+
+	return send(rth->fd, &req, sizeof(req), 0);
+}
+
+int rtnl_addrlbldump_req(struct rtnl_handle *rth, int family)
+{
+	struct {
+		struct nlmsghdr nlh;
+		struct ifaddrlblmsg ifal;
+	} req = {
+		.nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifaddrlblmsg)),
+		.nlh.nlmsg_type = RTM_GETADDRLABEL,
+		.nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,
+		.nlh.nlmsg_seq = rth->dump = ++rth->seq,
+		.ifal.ifal_family = family,
+	};
+
+	return send(rth->fd, &req, sizeof(req), 0);
+}
+
+int rtnl_routedump_req(struct rtnl_handle *rth, int family,
+		       req_filter_fn_t filter_fn)
+{
+	struct {
+		struct nlmsghdr nlh;
+		struct rtmsg rtm;
+		char buf[128];
+	} req = {
+		.nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct rtmsg)),
+		.nlh.nlmsg_type = RTM_GETROUTE,
+		.nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,
+		.nlh.nlmsg_seq = rth->dump = ++rth->seq,
+		.rtm.rtm_family = family,
+	};
+
+	if (filter_fn) {
+		int err;
+
+		err = filter_fn(&req.nlh, sizeof(req));
+		if (err)
+			return err;
+	}
+
+	return send(rth->fd, &req, sizeof(req), 0);
+}
+
+int rtnl_ruledump_req(struct rtnl_handle *rth, int family)
+{
+	struct {
+		struct nlmsghdr nlh;
+		struct fib_rule_hdr frh;
+	} req = {
+		.nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct fib_rule_hdr)),
+		.nlh.nlmsg_type = RTM_GETRULE,
+		.nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,
+		.nlh.nlmsg_seq = rth->dump = ++rth->seq,
+		.frh.family = family
+	};
+
+	return send(rth->fd, &req, sizeof(req), 0);
+}
+
+int rtnl_neighdump_req(struct rtnl_handle *rth, int family,
+		       req_filter_fn_t filter_fn)
+{
+	struct {
+		struct nlmsghdr nlh;
+		struct ndmsg ndm;
+		char buf[256];
+	} req = {
+		.nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct ndmsg)),
+		.nlh.nlmsg_type = RTM_GETNEIGH,
+		.nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,
+		.nlh.nlmsg_seq = rth->dump = ++rth->seq,
+		.ndm.ndm_family = family,
+	};
+
+	if (filter_fn) {
+		int err;
+
+		err = filter_fn(&req.nlh, sizeof(req));
+		if (err)
+			return err;
+	}
+
+	return send(rth->fd, &req, sizeof(req), 0);
+}
+
+int rtnl_neightbldump_req(struct rtnl_handle *rth, int family)
+{
+	struct {
+		struct nlmsghdr nlh;
+		struct ndtmsg ndtmsg;
+	} req = {
+		.nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct ndtmsg)),
+		.nlh.nlmsg_type = RTM_GETNEIGHTBL,
+		.nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,
+		.nlh.nlmsg_seq = rth->dump = ++rth->seq,
+		.ndtmsg.ndtm_family = family,
+	};
+
+	return send(rth->fd, &req, sizeof(req), 0);
+}
+
+int rtnl_mdbdump_req(struct rtnl_handle *rth, int family)
+{
+	struct {
+		struct nlmsghdr nlh;
+		struct br_port_msg bpm;
+	} req = {
+		.nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct br_port_msg)),
+		.nlh.nlmsg_type = RTM_GETMDB,
+		.nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,
+		.nlh.nlmsg_seq = rth->dump = ++rth->seq,
+		.bpm.family = family,
+	};
+
+	return send(rth->fd, &req, sizeof(req), 0);
+}
+
+int rtnl_brvlandump_req(struct rtnl_handle *rth, int family, __u32 dump_flags)
+{
+	struct {
+		struct nlmsghdr nlh;
+		struct br_vlan_msg bvm;
+		char buf[256];
+	} req = {
+		.nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct br_vlan_msg)),
+		.nlh.nlmsg_type = RTM_GETVLAN,
+		.nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,
+		.nlh.nlmsg_seq = rth->dump = ++rth->seq,
+		.bvm.family = family,
+	};
+
+	addattr32(&req.nlh, sizeof(req), BRIDGE_VLANDB_DUMP_FLAGS, dump_flags);
+
+	return send(rth->fd, &req, sizeof(req), 0);
+}
+
+int rtnl_netconfdump_req(struct rtnl_handle *rth, int family)
+{
+	struct {
+		struct nlmsghdr nlh;
+		struct netconfmsg ncm;
+		char buf[0] __aligned(NLMSG_ALIGNTO);
+	} req = {
+		.nlh.nlmsg_len = NLMSG_LENGTH(NLMSG_ALIGN(sizeof(struct netconfmsg))),
+		.nlh.nlmsg_type = RTM_GETNETCONF,
+		.nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,
+		.nlh.nlmsg_seq = rth->dump = ++rth->seq,
+		.ncm.ncm_family = family,
+	};
+
+	return send(rth->fd, &req, sizeof(req), 0);
+}
+
+int rtnl_nsiddump_req_filter_fn(struct rtnl_handle *rth, int family,
+				req_filter_fn_t filter_fn)
+{
+	struct {
+		struct nlmsghdr nlh;
+		struct rtgenmsg rtm;
+		char buf[1024];
+	} req = {
+		.nlh.nlmsg_len = NLMSG_LENGTH(NLMSG_ALIGN(sizeof(struct rtgenmsg))),
+		.nlh.nlmsg_type = RTM_GETNSID,
+		.nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,
+		.nlh.nlmsg_seq = rth->dump = ++rth->seq,
+		.rtm.rtgen_family = family,
+	};
+	int err;
+
+	if (!filter_fn)
+		return -EINVAL;
+
+	err = filter_fn(&req.nlh, sizeof(req));
+	if (err)
+		return err;
+
+	return send(rth->fd, &req, req.nlh.nlmsg_len, 0);
+}
+
+static int __rtnl_linkdump_req(struct rtnl_handle *rth, int family)
+{
+	struct {
+		struct nlmsghdr nlh;
+		struct ifinfomsg ifm;
+	} req = {
+		.nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifinfomsg)),
+		.nlh.nlmsg_type = RTM_GETLINK,
+		.nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,
+		.nlh.nlmsg_seq = rth->dump = ++rth->seq,
+		.ifm.ifi_family = family,
+	};
+
+	return send(rth->fd, &req, sizeof(req), 0);
+}
+
+int rtnl_linkdump_req(struct rtnl_handle *rth, int family)
+{
+	if (family == AF_UNSPEC)
+		return rtnl_linkdump_req_filter(rth, family, RTEXT_FILTER_VF);
+
+	return __rtnl_linkdump_req(rth, family);
+}
+
+int rtnl_linkdump_req_filter(struct rtnl_handle *rth, int family,
+			    __u32 filt_mask)
+{
+	if (family == AF_UNSPEC || family == AF_BRIDGE) {
+		struct {
+			struct nlmsghdr nlh;
+			struct ifinfomsg ifm;
+			/* attribute has to be NLMSG aligned */
+			struct rtattr ext_req __aligned(NLMSG_ALIGNTO);
+			__u32 ext_filter_mask;
+		} req = {
+			.nlh.nlmsg_len = sizeof(req),
+			.nlh.nlmsg_type = RTM_GETLINK,
+			.nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,
+			.nlh.nlmsg_seq = rth->dump = ++rth->seq,
+			.ifm.ifi_family = family,
+			.ext_req.rta_type = IFLA_EXT_MASK,
+			.ext_req.rta_len = RTA_LENGTH(sizeof(__u32)),
+			.ext_filter_mask = filt_mask,
+		};
+
+		return send(rth->fd, &req, sizeof(req), 0);
+	}
+
+	return __rtnl_linkdump_req(rth, family);
+}
+
+int rtnl_linkdump_req_filter_fn(struct rtnl_handle *rth, int family,
+				req_filter_fn_t filter_fn)
+{
+	if (family == AF_UNSPEC || family == AF_PACKET) {
+		struct {
+			struct nlmsghdr nlh;
+			struct ifinfomsg ifm;
+			char buf[1024];
+		} req = {
+			.nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifinfomsg)),
+			.nlh.nlmsg_type = RTM_GETLINK,
+			.nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,
+			.nlh.nlmsg_seq = rth->dump = ++rth->seq,
+			.ifm.ifi_family = family,
+		};
+		int err;
+
+		if (!filter_fn)
+			return -EINVAL;
+
+		err = filter_fn(&req.nlh, sizeof(req));
+		if (err)
+			return err;
+
+		return send(rth->fd, &req, req.nlh.nlmsg_len, 0);
+	}
+
+	return __rtnl_linkdump_req(rth, family);
+}
+
+int rtnl_fdb_linkdump_req_filter_fn(struct rtnl_handle *rth,
+				    req_filter_fn_t filter_fn)
+{
+	struct {
+		struct nlmsghdr nlh;
+		struct ifinfomsg ifm;
+		char buf[128];
+	} req = {
+		.nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifinfomsg)),
+		.nlh.nlmsg_type = RTM_GETNEIGH,
+		.nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,
+		.nlh.nlmsg_seq = rth->dump = ++rth->seq,
+		.ifm.ifi_family = PF_BRIDGE,
+	};
+	int err;
+
+	err = filter_fn(&req.nlh, sizeof(req));
+	if (err)
+		return err;
+
+	return send(rth->fd, &req, sizeof(req), 0);
+}
+
+int rtnl_statsdump_req_filter(struct rtnl_handle *rth, int fam,
+			      __u32 filt_mask,
+			      int (*filter_fn)(struct ipstats_req *req,
+					       void *data),
+			      void *filter_data)
+{
+	struct ipstats_req req;
+
+	memset(&req, 0, sizeof(req));
+	req.nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct if_stats_msg));
+	req.nlh.nlmsg_type = RTM_GETSTATS;
+	req.nlh.nlmsg_flags = NLM_F_DUMP|NLM_F_REQUEST;
+	req.nlh.nlmsg_pid = 0;
+	req.nlh.nlmsg_seq = rth->dump = ++rth->seq;
+	req.ifsm.family = fam;
+	req.ifsm.filter_mask = filt_mask;
+
+	if (filter_fn) {
+		int err;
+
+		err = filter_fn(&req, filter_data);
+		if (err)
+			return err;
+	}
+
+	return send(rth->fd, &req, sizeof(req), 0);
+}
+
+int rtnl_send(struct rtnl_handle *rth, const void *buf, int len)
+{
+	return send(rth->fd, buf, len, 0);
+}
+
+int rtnl_send_check(struct rtnl_handle *rth, const void *buf, int len)
+{
+	struct nlmsghdr *h;
+	int status;
+	char resp[1024];
+
+	status = send(rth->fd, buf, len, 0);
+	if (status < 0)
+		return status;
+
+	/* Check for immediate errors */
+	status = recv(rth->fd, resp, sizeof(resp), MSG_DONTWAIT|MSG_PEEK);
+	if (status < 0) {
+		if (errno == EAGAIN)
+			return 0;
+		return -1;
+	}
+
+	for (h = (struct nlmsghdr *)resp; NLMSG_OK(h, status);
+	     h = NLMSG_NEXT(h, status)) {
+		if (h->nlmsg_type == NLMSG_ERROR) {
+			struct nlmsgerr *err = (struct nlmsgerr *)NLMSG_DATA(h);
+
+			if (h->nlmsg_len < NLMSG_LENGTH(sizeof(struct nlmsgerr)))
+				fprintf(stderr, "ERROR truncated\n");
+			else
+				errno = -err->error;
+			return -1;
+		}
+	}
+
+	return 0;
+}
+
+int rtnl_dump_request(struct rtnl_handle *rth, int type, void *req, int len)
+{
+	struct nlmsghdr nlh = {
+		.nlmsg_len = NLMSG_LENGTH(len),
+		.nlmsg_type = type,
+		.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,
+		.nlmsg_seq = rth->dump = ++rth->seq,
+	};
+	struct sockaddr_nl nladdr = { .nl_family = AF_NETLINK };
+	struct iovec iov[2] = {
+		{ .iov_base = &nlh, .iov_len = sizeof(nlh) },
+		{ .iov_base = req, .iov_len = len }
+	};
+	struct msghdr msg = {
+		.msg_name = &nladdr,
+		.msg_namelen = sizeof(nladdr),
+		.msg_iov = iov,
+		.msg_iovlen = 2,
+	};
+
+	return sendmsg(rth->fd, &msg, 0);
+}
+
+int rtnl_dump_request_n(struct rtnl_handle *rth, struct nlmsghdr *n)
+{
+	struct sockaddr_nl nladdr = { .nl_family = AF_NETLINK };
+	struct iovec iov = {
+		.iov_base = n,
+		.iov_len = n->nlmsg_len
+	};
+	struct msghdr msg = {
+		.msg_name = &nladdr,
+		.msg_namelen = sizeof(nladdr),
+		.msg_iov = &iov,
+		.msg_iovlen = 1,
+	};
+
+	n->nlmsg_flags = NLM_F_DUMP|NLM_F_REQUEST;
+	n->nlmsg_pid = 0;
+	n->nlmsg_seq = rth->dump = ++rth->seq;
+
+	return sendmsg(rth->fd, &msg, 0);
+}
+
+static int rtnl_dump_done(struct nlmsghdr *h,
+			  const struct rtnl_dump_filter_arg *a)
+{
+	int len = *(int *)NLMSG_DATA(h);
+
+	if (h->nlmsg_len < NLMSG_LENGTH(sizeof(int))) {
+		fprintf(stderr, "DONE truncated\n");
+		return -1;
+	}
+
+	if (len < 0) {
+		errno = -len;
+
+		if (a->errhndlr && (a->errhndlr(h, a->arg2) & RTNL_SUPPRESS_NLMSG_DONE_NLERR))
+			return 0;
+
+		/* check for any messages returned from kernel */
+		if (nl_dump_ext_ack_done(h, sizeof(int), len))
+			return len;
+
+		switch (errno) {
+		case ENOENT:
+		case EOPNOTSUPP:
+			return -1;
+		case EMSGSIZE:
+			fprintf(stderr,
+				"Error: Buffer too small for object.\n");
+			break;
+		default:
+			perror("RTNETLINK answers");
+		}
+		return len;
+	}
+
+	/* check for any messages returned from kernel */
+	nl_dump_ext_ack(h, NULL);
+
+	return 0;
+}
+
+static int rtnl_dump_error(const struct rtnl_handle *rth,
+			    struct nlmsghdr *h,
+			    const struct rtnl_dump_filter_arg *a)
+{
+
+	if (h->nlmsg_len < NLMSG_LENGTH(sizeof(struct nlmsgerr))) {
+		fprintf(stderr, "ERROR truncated\n");
+	} else {
+		const struct nlmsgerr *err = (struct nlmsgerr *)NLMSG_DATA(h);
+
+		errno = -err->error;
+		if (rth->proto == NETLINK_SOCK_DIAG &&
+		    (errno == ENOENT ||
+		     errno == EOPNOTSUPP))
+			return -1;
+
+		if (a->errhndlr && (a->errhndlr(h, a->arg2) & RTNL_SUPPRESS_NLMSG_ERROR_NLERR))
+			return 0;
+
+		if (!(rth->flags & RTNL_HANDLE_F_SUPPRESS_NLERR))
+			perror("RTNETLINK answers");
+	}
+
+	return -1;
+}
+
+static int __rtnl_recvmsg(int fd, struct msghdr *msg, int flags)
+{
+	int len;
+
+	do {
+		len = recvmsg(fd, msg, flags);
+	} while (len < 0 && (errno == EINTR || errno == EAGAIN));
+
+	if (len < 0) {
+		fprintf(stderr, "netlink receive error %s (%d)\n",
+			strerror(errno), errno);
+		return -errno;
+	}
+
+	if (len == 0) {
+		fprintf(stderr, "EOF on netlink\n");
+		return -ENODATA;
+	}
+
+	return len;
+}
+
+static int rtnl_recvmsg(int fd, struct msghdr *msg, char **answer)
+{
+	struct iovec *iov = msg->msg_iov;
+	char *buf;
+	int len;
+
+	iov->iov_base = NULL;
+	iov->iov_len = 0;
+
+	len = __rtnl_recvmsg(fd, msg, MSG_PEEK | MSG_TRUNC);
+	if (len < 0)
+		return len;
+
+	if (len < 32768)
+		len = 32768;
+	buf = malloc(len);
+	if (!buf) {
+		fprintf(stderr, "malloc error: not enough buffer\n");
+		return -ENOMEM;
+	}
+
+	iov->iov_base = buf;
+	iov->iov_len = len;
+
+	len = __rtnl_recvmsg(fd, msg, 0);
+	if (len < 0) {
+		free(buf);
+		return len;
+	}
+
+	if (answer)
+		*answer = buf;
+	else
+		free(buf);
+
+	return len;
+}
+
+static int rtnl_dump_filter_l(struct rtnl_handle *rth,
+			      const struct rtnl_dump_filter_arg *arg)
+{
+	struct sockaddr_nl nladdr;
+	struct iovec iov;
+	struct msghdr msg = {
+		.msg_name = &nladdr,
+		.msg_namelen = sizeof(nladdr),
+		.msg_iov = &iov,
+		.msg_iovlen = 1,
+	};
+	char *buf;
+	int dump_intr = 0;
+
+	while (1) {
+		int status;
+		const struct rtnl_dump_filter_arg *a;
+		int found_done = 0;
+		int msglen = 0;
+
+		status = rtnl_recvmsg(rth->fd, &msg, &buf);
+		if (status < 0)
+			return status;
+
+		if (rth->dump_fp)
+			fwrite(buf, 1, NLMSG_ALIGN(status), rth->dump_fp);
+
+		for (a = arg; a->filter; a++) {
+			struct nlmsghdr *h = (struct nlmsghdr *)buf;
+
+			msglen = status;
+
+			while (NLMSG_OK(h, msglen)) {
+				int err = 0;
+
+				h->nlmsg_flags &= ~a->nc_flags;
+
+				if (nladdr.nl_pid != 0 ||
+				    h->nlmsg_pid != rth->local.nl_pid ||
+				    h->nlmsg_seq != rth->dump)
+					goto skip_it;
+
+				if (h->nlmsg_flags & NLM_F_DUMP_INTR)
+					dump_intr = 1;
+
+				if (h->nlmsg_type == NLMSG_DONE) {
+					err = rtnl_dump_done(h, a);
+					if (err < 0) {
+						free(buf);
+						return -1;
+					}
+
+					found_done = 1;
+					break; /* process next filter */
+				}
+
+				if (h->nlmsg_type == NLMSG_ERROR) {
+					err = rtnl_dump_error(rth, h, a);
+					if (err < 0) {
+						free(buf);
+						return -1;
+					}
+
+					goto skip_it;
+				}
+
+				if (!rth->dump_fp) {
+					err = a->filter(h, a->arg1);
+					if (err < 0) {
+						free(buf);
+						return err;
+					}
+				}
+
+skip_it:
+				h = NLMSG_NEXT(h, msglen);
+			}
+		}
+		free(buf);
+
+		if (found_done) {
+			if (dump_intr)
+				fprintf(stderr,
+					"Dump was interrupted and may be inconsistent.\n");
+			return 0;
+		}
+
+		if (msg.msg_flags & MSG_TRUNC) {
+			fprintf(stderr, "Message truncated\n");
+			continue;
+		}
+		if (msglen) {
+			fprintf(stderr, "!!!Remnant of size %d\n", msglen);
+			exit(1);
+		}
+	}
+}
+
+int rtnl_dump_filter_nc(struct rtnl_handle *rth,
+			rtnl_filter_t filter,
+			void *arg1, __u16 nc_flags)
+{
+	const struct rtnl_dump_filter_arg a[] = {
+		{
+			.filter = filter, .arg1 = arg1,
+			.nc_flags = nc_flags,
+		},
+		{ },
+	};
+
+	return rtnl_dump_filter_l(rth, a);
+}
+
+int rtnl_dump_filter_errhndlr_nc(struct rtnl_handle *rth,
+		     rtnl_filter_t filter,
+		     void *arg1,
+		     rtnl_err_hndlr_t errhndlr,
+		     void *arg2,
+		     __u16 nc_flags)
+{
+	const struct rtnl_dump_filter_arg a[] = {
+		{
+			.filter = filter, .arg1 = arg1,
+			.errhndlr = errhndlr, .arg2 = arg2,
+			.nc_flags = nc_flags,
+		},
+		{ },
+	};
+
+	return rtnl_dump_filter_l(rth, a);
+}
+
+static void rtnl_talk_error(struct nlmsghdr *h, struct nlmsgerr *err,
+			    nl_ext_ack_fn_t errfn)
+{
+	if (nl_dump_ext_ack(h, errfn))
+		return;
+
+	fprintf(stderr, "RTNETLINK answers: %s\n",
+		strerror(-err->error));
+}
+
+
+static int __rtnl_talk_iov(struct rtnl_handle *rtnl, struct iovec *iov,
+			   size_t iovlen, struct nlmsghdr **answer,
+			   bool show_rtnl_err, nl_ext_ack_fn_t errfn)
+{
+	struct sockaddr_nl nladdr = { .nl_family = AF_NETLINK };
+	struct iovec riov;
+	struct msghdr msg = {
+		.msg_name = &nladdr,
+		.msg_namelen = sizeof(nladdr),
+		.msg_iov = iov,
+		.msg_iovlen = iovlen,
+	};
+	unsigned int seq = 0;
+	struct nlmsghdr *h;
+	int i, status;
+	char *buf;
+
+	for (i = 0; i < iovlen; i++) {
+		h = iov[i].iov_base;
+		h->nlmsg_seq = seq = ++rtnl->seq;
+		if (answer == NULL)
+			h->nlmsg_flags |= NLM_F_ACK;
+	}
+
+	status = sendmsg(rtnl->fd, &msg, 0);
+	if (status < 0) {
+		perror("Cannot talk to rtnetlink");
+		return -1;
+	}
+
+	/* change msg to use the response iov */
+	msg.msg_iov = &riov;
+	msg.msg_iovlen = 1;
+	i = 0;
+	while (1) {
+next:
+		status = rtnl_recvmsg(rtnl->fd, &msg, &buf);
+		++i;
+
+		if (status < 0)
+			return status;
+
+		if (msg.msg_namelen != sizeof(nladdr)) {
+			fprintf(stderr,
+				"sender address length == %d\n",
+				msg.msg_namelen);
+			exit(1);
+		}
+		for (h = (struct nlmsghdr *)buf; status >= sizeof(*h); ) {
+			int len = h->nlmsg_len;
+			int l = len - sizeof(*h);
+
+			if (l < 0 || len > status) {
+				if (msg.msg_flags & MSG_TRUNC) {
+					fprintf(stderr, "Truncated message\n");
+					free(buf);
+					return -1;
+				}
+				fprintf(stderr,
+					"!!!malformed message: len=%d\n",
+					len);
+				exit(1);
+			}
+
+			if (nladdr.nl_pid != 0 ||
+			    h->nlmsg_pid != rtnl->local.nl_pid ||
+			    h->nlmsg_seq > seq || h->nlmsg_seq < seq - iovlen) {
+				/* Don't forget to skip that message. */
+				status -= NLMSG_ALIGN(len);
+				h = (struct nlmsghdr *)((char *)h + NLMSG_ALIGN(len));
+				continue;
+			}
+
+			if (h->nlmsg_type == NLMSG_ERROR) {
+				struct nlmsgerr *err = (struct nlmsgerr *)NLMSG_DATA(h);
+				int error = err->error;
+
+				if (l < sizeof(struct nlmsgerr)) {
+					fprintf(stderr, "ERROR truncated\n");
+					free(buf);
+					return -1;
+				}
+
+				if (!error) {
+					/* check messages from kernel */
+					nl_dump_ext_ack(h, errfn);
+				} else {
+					errno = -error;
+
+					if (rtnl->proto != NETLINK_SOCK_DIAG &&
+					    show_rtnl_err)
+						rtnl_talk_error(h, err, errfn);
+				}
+
+				if (i < iovlen) {
+					free(buf);
+					goto next;
+				}
+
+				if (error) {
+					free(buf);
+					return -i;
+				}
+
+				if (answer)
+					*answer = (struct nlmsghdr *)buf;
+				return 0;
+			}
+
+			if (answer) {
+				*answer = (struct nlmsghdr *)buf;
+				return 0;
+			}
+
+			fprintf(stderr, "Unexpected reply!!!\n");
+
+			status -= NLMSG_ALIGN(len);
+			h = (struct nlmsghdr *)((char *)h + NLMSG_ALIGN(len));
+		}
+		free(buf);
+
+		if (msg.msg_flags & MSG_TRUNC) {
+			fprintf(stderr, "Message truncated\n");
+			continue;
+		}
+
+		if (status) {
+			fprintf(stderr, "!!!Remnant of size %d\n", status);
+			exit(1);
+		}
+	}
+}
+
+static int __rtnl_talk(struct rtnl_handle *rtnl, struct nlmsghdr *n,
+		       struct nlmsghdr **answer,
+		       bool show_rtnl_err, nl_ext_ack_fn_t errfn)
+{
+	struct iovec iov = {
+		.iov_base = n,
+		.iov_len = n->nlmsg_len
+	};
+
+	return __rtnl_talk_iov(rtnl, &iov, 1, answer, show_rtnl_err, errfn);
+}
+
+int rtnl_echo_talk(struct rtnl_handle *rtnl, struct nlmsghdr *n, int json,
+		   int (*print_info)(struct nlmsghdr *n, void *arg))
+{
+	struct nlmsghdr *answer;
+	int ret;
+
+	n->nlmsg_flags |= NLM_F_ECHO | NLM_F_ACK;
+
+	ret = rtnl_talk(rtnl, n, &answer);
+	if (ret)
+		return ret;
+
+	new_json_obj(json);
+	open_json_object(NULL);
+	print_info(answer, stdout);
+	close_json_object();
+	delete_json_obj();
+	free(answer);
+
+	return 0;
+}
+
+int rtnl_talk(struct rtnl_handle *rtnl, struct nlmsghdr *n,
+	      struct nlmsghdr **answer)
+{
+	return __rtnl_talk(rtnl, n, answer, true, NULL);
+}
+
+int rtnl_talk_iov(struct rtnl_handle *rtnl, struct iovec *iovec, size_t iovlen,
+		  struct nlmsghdr **answer)
+{
+	return __rtnl_talk_iov(rtnl, iovec, iovlen, answer, true, NULL);
+}
+
+int rtnl_talk_suppress_rtnl_errmsg(struct rtnl_handle *rtnl, struct nlmsghdr *n,
+				   struct nlmsghdr **answer)
+{
+	return __rtnl_talk(rtnl, n, answer, false, NULL);
+}
+
+int rtnl_listen_all_nsid(struct rtnl_handle *rth)
+{
+	unsigned int on = 1;
+
+	if (setsockopt(rth->fd, SOL_NETLINK, NETLINK_LISTEN_ALL_NSID, &on,
+		       sizeof(on)) < 0) {
+		perror("NETLINK_LISTEN_ALL_NSID");
+		return -1;
+	}
+	rth->flags |= RTNL_HANDLE_F_LISTEN_ALL_NSID;
+	return 0;
+}
+
+int rtnl_listen(struct rtnl_handle *rtnl,
+		rtnl_listen_filter_t handler,
+		void *jarg)
+{
+	int status;
+	struct nlmsghdr *h;
+	struct sockaddr_nl nladdr = { .nl_family = AF_NETLINK };
+	struct iovec iov;
+	struct msghdr msg = {
+		.msg_name = &nladdr,
+		.msg_namelen = sizeof(nladdr),
+		.msg_iov = &iov,
+		.msg_iovlen = 1,
+	};
+	char   buf[16384];
+	char   cmsgbuf[BUFSIZ];
+
+	iov.iov_base = buf;
+	while (1) {
+		struct rtnl_ctrl_data ctrl;
+		struct cmsghdr *cmsg;
+
+		if (rtnl->flags & RTNL_HANDLE_F_LISTEN_ALL_NSID) {
+			msg.msg_control = &cmsgbuf;
+			msg.msg_controllen = sizeof(cmsgbuf);
+		}
+
+		iov.iov_len = sizeof(buf);
+		status = recvmsg(rtnl->fd, &msg, 0);
+
+		if (status < 0) {
+			if (errno == EINTR || errno == EAGAIN)
+				continue;
+			fprintf(stderr, "netlink receive error %s (%d)\n",
+				strerror(errno), errno);
+			if (errno == ENOBUFS)
+				continue;
+			return -1;
+		}
+		if (status == 0) {
+			fprintf(stderr, "EOF on netlink\n");
+			return -1;
+		}
+		if (msg.msg_namelen != sizeof(nladdr)) {
+			fprintf(stderr,
+				"Sender address length == %d\n",
+				msg.msg_namelen);
+			exit(1);
+		}
+
+		if (rtnl->flags & RTNL_HANDLE_F_LISTEN_ALL_NSID) {
+			memset(&ctrl, 0, sizeof(ctrl));
+			ctrl.nsid = -1;
+			for (cmsg = CMSG_FIRSTHDR(&msg); cmsg;
+			     cmsg = CMSG_NXTHDR(&msg, cmsg))
+				if (cmsg->cmsg_level == SOL_NETLINK &&
+				    cmsg->cmsg_type == NETLINK_LISTEN_ALL_NSID &&
+				    cmsg->cmsg_len == CMSG_LEN(sizeof(int))) {
+					int *data = (int *)CMSG_DATA(cmsg);
+
+					ctrl.nsid = *data;
+				}
+		}
+
+		for (h = (struct nlmsghdr *)buf; status >= sizeof(*h); ) {
+			int err;
+			int len = h->nlmsg_len;
+			int l = len - sizeof(*h);
+
+			if (l < 0 || len > status) {
+				if (msg.msg_flags & MSG_TRUNC) {
+					fprintf(stderr, "Truncated message\n");
+					return -1;
+				}
+				fprintf(stderr,
+					"!!!malformed message: len=%d\n",
+					len);
+				exit(1);
+			}
+
+			err = handler(&ctrl, h, jarg);
+			if (err < 0)
+				return err;
+
+			status -= NLMSG_ALIGN(len);
+			h = (struct nlmsghdr *)((char *)h + NLMSG_ALIGN(len));
+		}
+		if (msg.msg_flags & MSG_TRUNC) {
+			fprintf(stderr, "Message truncated\n");
+			continue;
+		}
+		if (status) {
+			fprintf(stderr, "!!!Remnant of size %d\n", status);
+			exit(1);
+		}
+	}
+}
+
+int rtnl_from_file(FILE *rtnl, rtnl_listen_filter_t handler,
+		   void *jarg)
+{
+	size_t status;
+	char buf[16384];
+	struct nlmsghdr *h = (struct nlmsghdr *)buf;
+
+	while (1) {
+		int err, len;
+		int l;
+
+		status = fread(&buf, 1, sizeof(*h), rtnl);
+
+		if (status == 0 && feof(rtnl))
+			return 0;
+		if (status != sizeof(*h)) {
+			if (ferror(rtnl))
+				perror("rtnl_from_file: fread");
+			if (feof(rtnl))
+				fprintf(stderr, "rtnl-from_file: truncated message\n");
+			return -1;
+		}
+
+		len = h->nlmsg_len;
+		l = len - sizeof(*h);
+
+		if (l < 0 || len > sizeof(buf)) {
+			fprintf(stderr, "!!!malformed message: len=%d @%lu\n",
+				len, ftell(rtnl));
+			return -1;
+		}
+
+		status = fread(NLMSG_DATA(h), 1, NLMSG_ALIGN(l), rtnl);
+
+		if (status != NLMSG_ALIGN(l)) {
+			if (ferror(rtnl))
+				perror("rtnl_from_file: fread");
+			if (feof(rtnl))
+				fprintf(stderr, "rtnl-from_file: truncated message\n");
+			return -1;
+		}
+
+		err = handler(NULL, h, jarg);
+		if (err < 0)
+			return err;
+	}
+}
+
+int addattr(struct nlmsghdr *n, int maxlen, int type)
+{
+	return addattr_l(n, maxlen, type, NULL, 0);
+}
+
+int addattr8(struct nlmsghdr *n, int maxlen, int type, __u8 data)
+{
+	return addattr_l(n, maxlen, type, &data, sizeof(__u8));
+}
+
+int addattr16(struct nlmsghdr *n, int maxlen, int type, __u16 data)
+{
+	return addattr_l(n, maxlen, type, &data, sizeof(__u16));
+}
+
+int addattr32(struct nlmsghdr *n, int maxlen, int type, __u32 data)
+{
+	return addattr_l(n, maxlen, type, &data, sizeof(__u32));
+}
+
+int addattr64(struct nlmsghdr *n, int maxlen, int type, __u64 data)
+{
+	return addattr_l(n, maxlen, type, &data, sizeof(__u64));
+}
+
+int addattrstrz(struct nlmsghdr *n, int maxlen, int type, const char *str)
+{
+	return addattr_l(n, maxlen, type, str, strlen(str)+1);
+}
+
+int addattr_l(struct nlmsghdr *n, int maxlen, int type, const void *data,
+	      int alen)
+{
+	int len = RTA_LENGTH(alen);
+	struct rtattr *rta;
+
+	if (NLMSG_ALIGN(n->nlmsg_len) + RTA_ALIGN(len) > maxlen) {
+		fprintf(stderr,
+			"addattr_l ERROR: message exceeded bound of %d\n",
+			maxlen);
+		return -1;
+	}
+	rta = NLMSG_TAIL(n);
+	rta->rta_type = type;
+	rta->rta_len = len;
+	if (alen)
+		memcpy(RTA_DATA(rta), data, alen);
+	n->nlmsg_len = NLMSG_ALIGN(n->nlmsg_len) + RTA_ALIGN(len);
+	return 0;
+}
+
+int addraw_l(struct nlmsghdr *n, int maxlen, const void *data, int len)
+{
+	if (NLMSG_ALIGN(n->nlmsg_len) + NLMSG_ALIGN(len) > maxlen) {
+		fprintf(stderr,
+			"addraw_l ERROR: message exceeded bound of %d\n",
+			maxlen);
+		return -1;
+	}
+
+	memcpy(NLMSG_TAIL(n), data, len);
+	memset((void *) NLMSG_TAIL(n) + len, 0, NLMSG_ALIGN(len) - len);
+	n->nlmsg_len = NLMSG_ALIGN(n->nlmsg_len) + NLMSG_ALIGN(len);
+	return 0;
+}
+
+struct rtattr *addattr_nest(struct nlmsghdr *n, int maxlen, int type)
+{
+	struct rtattr *nest = NLMSG_TAIL(n);
+
+	addattr_l(n, maxlen, type, NULL, 0);
+	return nest;
+}
+
+int addattr_nest_end(struct nlmsghdr *n, struct rtattr *nest)
+{
+	nest->rta_len = (void *)NLMSG_TAIL(n) - (void *)nest;
+	return n->nlmsg_len;
+}
+
+struct rtattr *addattr_nest_compat(struct nlmsghdr *n, int maxlen, int type,
+				   const void *data, int len)
+{
+	struct rtattr *start = NLMSG_TAIL(n);
+
+	addattr_l(n, maxlen, type, data, len);
+	addattr_nest(n, maxlen, type);
+	return start;
+}
+
+int addattr_nest_compat_end(struct nlmsghdr *n, struct rtattr *start)
+{
+	struct rtattr *nest = (void *)start + NLMSG_ALIGN(start->rta_len);
+
+	start->rta_len = (void *)NLMSG_TAIL(n) - (void *)start;
+	addattr_nest_end(n, nest);
+	return n->nlmsg_len;
+}
+
+int rta_addattr32(struct rtattr *rta, int maxlen, int type, __u32 data)
+{
+	int len = RTA_LENGTH(4);
+	struct rtattr *subrta;
+
+	if (RTA_ALIGN(rta->rta_len) + len > maxlen) {
+		fprintf(stderr,
+			"rta_addattr32: Error! max allowed bound %d exceeded\n",
+			maxlen);
+		return -1;
+	}
+	subrta = (struct rtattr *)(((char *)rta) + RTA_ALIGN(rta->rta_len));
+	subrta->rta_type = type;
+	subrta->rta_len = len;
+	memcpy(RTA_DATA(subrta), &data, 4);
+	rta->rta_len = NLMSG_ALIGN(rta->rta_len) + len;
+	return 0;
+}
+
+int rta_addattr_l(struct rtattr *rta, int maxlen, int type,
+		  const void *data, int alen)
+{
+	struct rtattr *subrta;
+	int len = RTA_LENGTH(alen);
+
+	if (RTA_ALIGN(rta->rta_len) + RTA_ALIGN(len) > maxlen) {
+		fprintf(stderr,
+			"rta_addattr_l: Error! max allowed bound %d exceeded\n",
+			maxlen);
+		return -1;
+	}
+	subrta = (struct rtattr *)(((char *)rta) + RTA_ALIGN(rta->rta_len));
+	subrta->rta_type = type;
+	subrta->rta_len = len;
+	if (alen)
+		memcpy(RTA_DATA(subrta), data, alen);
+	rta->rta_len = NLMSG_ALIGN(rta->rta_len) + RTA_ALIGN(len);
+	return 0;
+}
+
+int rta_addattr8(struct rtattr *rta, int maxlen, int type, __u8 data)
+{
+	return rta_addattr_l(rta, maxlen, type, &data, sizeof(__u8));
+}
+
+int rta_addattr16(struct rtattr *rta, int maxlen, int type, __u16 data)
+{
+	return rta_addattr_l(rta, maxlen, type, &data, sizeof(__u16));
+}
+
+int rta_addattr64(struct rtattr *rta, int maxlen, int type, __u64 data)
+{
+	return rta_addattr_l(rta, maxlen, type, &data, sizeof(__u64));
+}
+
+struct rtattr *rta_nest(struct rtattr *rta, int maxlen, int type)
+{
+	struct rtattr *nest = RTA_TAIL(rta);
+
+	rta_addattr_l(rta, maxlen, type, NULL, 0);
+	nest->rta_type |= NLA_F_NESTED;
+
+	return nest;
+}
+
+int rta_nest_end(struct rtattr *rta, struct rtattr *nest)
+{
+	nest->rta_len = (void *)RTA_TAIL(rta) - (void *)nest;
+
+	return rta->rta_len;
+}
+
+int parse_rtattr(struct rtattr *tb[], int max, struct rtattr *rta, int len)
+{
+	return parse_rtattr_flags(tb, max, rta, len, 0);
+}
+
+int parse_rtattr_flags(struct rtattr *tb[], int max, struct rtattr *rta,
+		       int len, unsigned short flags)
+{
+	unsigned short type;
+
+	memset(tb, 0, sizeof(struct rtattr *) * (max + 1));
+	while (RTA_OK(rta, len)) {
+		type = rta->rta_type & ~flags;
+		if ((type <= max) && (!tb[type]))
+			tb[type] = rta;
+		rta = RTA_NEXT(rta, len);
+	}
+	if (len)
+		fprintf(stderr, "!!!Deficit %d, rta_len=%d\n",
+			len, rta->rta_len);
+	return 0;
+}
+
+struct rtattr *parse_rtattr_one(int type, struct rtattr *rta, int len)
+{
+	while (RTA_OK(rta, len)) {
+		if (rta->rta_type == type)
+			return rta;
+		rta = RTA_NEXT(rta, len);
+	}
+
+	if (len)
+		fprintf(stderr, "!!!Deficit %d, rta_len=%d\n",
+			len, rta->rta_len);
+	return NULL;
+}
+
+int __parse_rtattr_nested_compat(struct rtattr *tb[], int max,
+				 struct rtattr *rta,
+				 int len)
+{
+	if (RTA_PAYLOAD(rta) < len)
+		return -1;
+	if (RTA_PAYLOAD(rta) >= RTA_ALIGN(len) + sizeof(struct rtattr)) {
+		rta = RTA_DATA(rta) + RTA_ALIGN(len);
+		return parse_rtattr_nested(tb, max, rta);
+	}
+	memset(tb, 0, sizeof(struct rtattr *) * (max + 1));
+	return 0;
+}
+
+static const char *get_nla_type_str(unsigned int attr)
+{
+	switch (attr) {
+#define C(x) case NL_ATTR_TYPE_ ## x: return #x
+	C(U8);
+	C(U16);
+	C(U32);
+	C(U64);
+	C(STRING);
+	C(FLAG);
+	C(NESTED);
+	C(NESTED_ARRAY);
+	C(NUL_STRING);
+	C(BINARY);
+	C(S8);
+	C(S16);
+	C(S32);
+	C(S64);
+	C(BITFIELD32);
+	default:
+		return "unknown";
+	}
+}
+
+void nl_print_policy(const struct rtattr *attr, FILE *fp)
+{
+	const struct rtattr *pos;
+
+	rtattr_for_each_nested(pos, attr) {
+		const struct rtattr *attr;
+
+		fprintf(fp, " policy[%u]:", pos->rta_type & ~NLA_F_NESTED);
+
+		rtattr_for_each_nested(attr, pos) {
+			struct rtattr *tp[NL_POLICY_TYPE_ATTR_MAX + 1];
+
+			parse_rtattr_nested(tp, ARRAY_SIZE(tp) - 1, attr);
+
+			if (tp[NL_POLICY_TYPE_ATTR_TYPE])
+				fprintf(fp, "attr[%u]: type=%s",
+					attr->rta_type & ~NLA_F_NESTED,
+					get_nla_type_str(rta_getattr_u32(tp[NL_POLICY_TYPE_ATTR_TYPE])));
+
+			if (tp[NL_POLICY_TYPE_ATTR_POLICY_IDX])
+				fprintf(fp, " policy:%u",
+					rta_getattr_u32(tp[NL_POLICY_TYPE_ATTR_POLICY_IDX]));
+
+			if (tp[NL_POLICY_TYPE_ATTR_POLICY_MAXTYPE])
+				fprintf(fp, " maxattr:%u",
+					rta_getattr_u32(tp[NL_POLICY_TYPE_ATTR_POLICY_MAXTYPE]));
+
+			if (tp[NL_POLICY_TYPE_ATTR_MIN_VALUE_S] && tp[NL_POLICY_TYPE_ATTR_MAX_VALUE_S])
+				fprintf(fp, " range:[%lld,%lld]",
+					(signed long long)rta_getattr_u64(tp[NL_POLICY_TYPE_ATTR_MIN_VALUE_S]),
+					(signed long long)rta_getattr_u64(tp[NL_POLICY_TYPE_ATTR_MAX_VALUE_S]));
+
+			if (tp[NL_POLICY_TYPE_ATTR_MIN_VALUE_U] && tp[NL_POLICY_TYPE_ATTR_MAX_VALUE_U])
+				fprintf(fp, " range:[%llu,%llu]",
+					(unsigned long long)rta_getattr_u64(tp[NL_POLICY_TYPE_ATTR_MIN_VALUE_U]),
+					(unsigned long long)rta_getattr_u64(tp[NL_POLICY_TYPE_ATTR_MAX_VALUE_U]));
+
+			if (tp[NL_POLICY_TYPE_ATTR_MIN_LENGTH])
+				fprintf(fp, " min len:%u",
+					rta_getattr_u32(tp[NL_POLICY_TYPE_ATTR_MIN_LENGTH]));
+
+			if (tp[NL_POLICY_TYPE_ATTR_MAX_LENGTH])
+				fprintf(fp, " max len:%u",
+					rta_getattr_u32(tp[NL_POLICY_TYPE_ATTR_MAX_LENGTH]));
+		}
+	}
+}
+
+int rtnl_tunneldump_req(struct rtnl_handle *rth, int family, int ifindex,
+			__u8 flags)
+{
+	struct {
+		struct nlmsghdr nlh;
+		struct tunnel_msg tmsg;
+		char buf[256];
+	} req = {
+		.nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct tunnel_msg)),
+		.nlh.nlmsg_type = RTM_GETTUNNEL,
+		.nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,
+		.nlh.nlmsg_seq = rth->dump = ++rth->seq,
+		.tmsg.family = family,
+		.tmsg.flags = flags,
+		.tmsg.ifindex = ifindex,
+	};
+
+	return send(rth->fd, &req, sizeof(req), 0);
+}
diff --git a/lib/ll_addr.c b/lib/ll_addr.c
new file mode 100644
index 0000000..d6fd736
--- /dev/null
+++ b/lib/ll_addr.c
@@ -0,0 +1,95 @@
+/*
+ * ll_addr.c
+ *
+ *		This program is free software; you can redistribute it and/or
+ *		modify it under the terms of the GNU General Public License
+ *		as published by the Free Software Foundation; either version
+ *		2 of the License, or (at your option) any later version.
+ *
+ * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <string.h>
+
+#include <linux/netdevice.h>
+#include <linux/if_arp.h>
+#include <linux/sockios.h>
+
+#include "rt_names.h"
+#include "utils.h"
+
+const char *ll_addr_n2a(const unsigned char *addr, int alen, int type,
+			char *buf, int blen)
+{
+	int i;
+	int l;
+
+	if (alen == 4 &&
+	    (type == ARPHRD_TUNNEL || type == ARPHRD_SIT
+	     || type == ARPHRD_IPGRE))
+		return inet_ntop(AF_INET, addr, buf, blen);
+
+	if (alen == 16 && (type == ARPHRD_TUNNEL6 || type == ARPHRD_IP6GRE))
+		return inet_ntop(AF_INET6, addr, buf, blen);
+	if (alen == 7 && type == ARPHRD_AX25)
+		return ax25_ntop(AF_AX25, addr, buf, blen);
+	if (alen == 7 && type == ARPHRD_NETROM)
+		return netrom_ntop(AF_NETROM, addr, buf, blen);
+	if (alen == 5 && type == ARPHRD_ROSE)
+		return rose_ntop(AF_ROSE, addr, buf, blen);
+
+	snprintf(buf, blen, "%02x", addr[0]);
+	for (i = 1, l = 2; i < alen && l < blen; i++, l += 3)
+		snprintf(buf + l, blen - l, ":%02x", addr[i]);
+	return buf;
+}
+
+/*NB: lladdr is char * (rather than u8 *) because sa_data is char * (1003.1g) */
+int ll_addr_a2n(char *lladdr, int len, const char *arg)
+{
+	if (strchr(arg, '.')) {
+		inet_prefix pfx;
+		if (get_addr_1(&pfx, arg, AF_INET)) {
+			fprintf(stderr, "\"%s\" is invalid lladdr.\n", arg);
+			return -1;
+		}
+		if (len < 4)
+			return -1;
+		memcpy(lladdr, pfx.data, 4);
+		return 4;
+	} else {
+		int i;
+
+		for (i = 0; i < len; i++) {
+			int temp;
+			char *cp = strchr(arg, ':');
+			if (cp) {
+				*cp = 0;
+				cp++;
+			}
+			if (sscanf(arg, "%x", &temp) != 1) {
+				fprintf(stderr, "\"%s\" is invalid lladdr.\n",
+					arg);
+				return -1;
+			}
+			if (temp < 0 || temp > 255) {
+				fprintf(stderr, "\"%s\" is invalid lladdr.\n",
+					arg);
+				return -1;
+			}
+			lladdr[i] = temp;
+			if (!cp)
+				break;
+			arg = cp;
+		}
+		return i + 1;
+	}
+}
diff --git a/lib/ll_map.c b/lib/ll_map.c
new file mode 100644
index 0000000..70ea3d4
--- /dev/null
+++ b/lib/ll_map.c
@@ -0,0 +1,410 @@
+/*
+ * ll_map.c
+ *
+ *		This program is free software; you can redistribute it and/or
+ *		modify it under the terms of the GNU General Public License
+ *		as published by the Free Software Foundation; either version
+ *		2 of the License, or (at your option) any later version.
+ *
+ * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <string.h>
+#include <net/if.h>
+
+#include "libnetlink.h"
+#include "ll_map.h"
+#include "list.h"
+#include "utils.h"
+
+struct ll_cache {
+	struct hlist_node idx_hash;
+	struct hlist_node name_hash;
+	unsigned	flags;
+	unsigned 	index;
+	unsigned short	type;
+	struct list_head altnames_list;
+	char		name[];
+};
+
+#define IDXMAP_SIZE	1024
+static struct hlist_head idx_head[IDXMAP_SIZE];
+static struct hlist_head name_head[IDXMAP_SIZE];
+
+static struct ll_cache *ll_get_by_index(unsigned index)
+{
+	struct hlist_node *n;
+	unsigned h = index & (IDXMAP_SIZE - 1);
+
+	hlist_for_each(n, &idx_head[h]) {
+		struct ll_cache *im
+			= container_of(n, struct ll_cache, idx_hash);
+		if (im->index == index)
+			return im;
+	}
+
+	return NULL;
+}
+
+unsigned namehash(const char *str)
+{
+	unsigned hash = 5381;
+
+	while (*str)
+		hash = ((hash << 5) + hash) + *str++; /* hash * 33 + c */
+
+	return hash;
+}
+
+static struct ll_cache *ll_get_by_name(const char *name)
+{
+	struct hlist_node *n;
+	unsigned h = namehash(name) & (IDXMAP_SIZE - 1);
+
+	hlist_for_each(n, &name_head[h]) {
+		struct ll_cache *im
+			= container_of(n, struct ll_cache, name_hash);
+
+		if (strcmp(im->name, name) == 0)
+			return im;
+	}
+
+	return NULL;
+}
+
+static struct ll_cache *ll_entry_create(struct ifinfomsg *ifi,
+					const char *ifname,
+					struct ll_cache *parent_im)
+{
+	struct ll_cache *im;
+	unsigned int h;
+
+	im = malloc(sizeof(*im) + strlen(ifname) + 1);
+	if (!im)
+		return NULL;
+	im->index = ifi->ifi_index;
+	strcpy(im->name, ifname);
+	im->type = ifi->ifi_type;
+	im->flags = ifi->ifi_flags;
+
+	if (parent_im) {
+		list_add_tail(&im->altnames_list, &parent_im->altnames_list);
+	} else {
+		/* This is parent, insert to index hash. */
+		h = ifi->ifi_index & (IDXMAP_SIZE - 1);
+		hlist_add_head(&im->idx_hash, &idx_head[h]);
+		INIT_LIST_HEAD(&im->altnames_list);
+	}
+
+	h = namehash(ifname) & (IDXMAP_SIZE - 1);
+	hlist_add_head(&im->name_hash, &name_head[h]);
+	return im;
+}
+
+static void ll_entry_destroy(struct ll_cache *im, bool im_is_parent)
+{
+	hlist_del(&im->name_hash);
+	if (im_is_parent)
+		hlist_del(&im->idx_hash);
+	else
+		list_del(&im->altnames_list);
+	free(im);
+}
+
+static void ll_entry_update(struct ll_cache *im, struct ifinfomsg *ifi,
+			    const char *ifname)
+{
+	unsigned int h;
+
+	im->flags = ifi->ifi_flags;
+	if (!strcmp(im->name, ifname))
+		return;
+	hlist_del(&im->name_hash);
+	h = namehash(ifname) & (IDXMAP_SIZE - 1);
+	hlist_add_head(&im->name_hash, &name_head[h]);
+}
+
+static void ll_altname_entries_create(struct ll_cache *parent_im,
+				      struct ifinfomsg *ifi, struct rtattr **tb)
+{
+	struct rtattr *i, *proplist = tb[IFLA_PROP_LIST];
+	int rem;
+
+	if (!proplist)
+		return;
+	rem = RTA_PAYLOAD(proplist);
+	for (i = RTA_DATA(proplist); RTA_OK(i, rem);
+	     i = RTA_NEXT(i, rem)) {
+		if (i->rta_type != IFLA_ALT_IFNAME)
+			continue;
+		ll_entry_create(ifi, rta_getattr_str(i), parent_im);
+	}
+}
+
+static void ll_altname_entries_destroy(struct ll_cache *parent_im)
+{
+	struct ll_cache *im, *tmp;
+
+	list_for_each_entry_safe(im, tmp, &parent_im->altnames_list,
+				 altnames_list)
+		ll_entry_destroy(im, false);
+}
+
+static void ll_altname_entries_update(struct ll_cache *parent_im,
+				      struct ifinfomsg *ifi, struct rtattr **tb)
+{
+	struct rtattr *i, *proplist = tb[IFLA_PROP_LIST];
+	struct ll_cache *im;
+	int rem;
+
+	if (!proplist) {
+		ll_altname_entries_destroy(parent_im);
+		return;
+	}
+
+	/* Simply compare the altname list with the cached one
+	 * and if it does not fit 1:1, recreate the cached list
+	 * from scratch.
+	 */
+	im = list_first_entry(&parent_im->altnames_list, typeof(*im),
+			      altnames_list);
+	rem = RTA_PAYLOAD(proplist);
+	for (i = RTA_DATA(proplist); RTA_OK(i, rem);
+	     i = RTA_NEXT(i, rem)) {
+		if (i->rta_type != IFLA_ALT_IFNAME)
+			continue;
+		if (!im || strcmp(rta_getattr_str(i), im->name))
+			goto recreate_altname_entries;
+		im = list_next_entry(im, altnames_list);
+	}
+	if (list_next_entry(im, altnames_list))
+		goto recreate_altname_entries;
+	return;
+
+recreate_altname_entries:
+	ll_altname_entries_destroy(parent_im);
+	ll_altname_entries_create(parent_im, ifi, tb);
+}
+
+static void ll_entries_create(struct ifinfomsg *ifi, struct rtattr **tb)
+{
+	struct ll_cache *parent_im;
+
+	if (!tb[IFLA_IFNAME])
+		return;
+	parent_im = ll_entry_create(ifi, rta_getattr_str(tb[IFLA_IFNAME]),
+				    NULL);
+	if (!parent_im)
+		return;
+	ll_altname_entries_create(parent_im, ifi, tb);
+}
+
+static void ll_entries_destroy(struct ll_cache *parent_im)
+{
+	ll_altname_entries_destroy(parent_im);
+	ll_entry_destroy(parent_im, true);
+}
+
+static void ll_entries_update(struct ll_cache *parent_im,
+			      struct ifinfomsg *ifi, struct rtattr **tb)
+{
+	if (tb[IFLA_IFNAME])
+		ll_entry_update(parent_im, ifi,
+				rta_getattr_str(tb[IFLA_IFNAME]));
+	ll_altname_entries_update(parent_im, ifi, tb);
+}
+
+int ll_remember_index(struct nlmsghdr *n, void *arg)
+{
+	struct ifinfomsg *ifi = NLMSG_DATA(n);
+	struct ll_cache *im;
+	struct rtattr *tb[IFLA_MAX+1];
+
+	if (n->nlmsg_type != RTM_NEWLINK && n->nlmsg_type != RTM_DELLINK)
+		return 0;
+
+	if (n->nlmsg_len < NLMSG_LENGTH(sizeof(*ifi)))
+		return -1;
+
+	im = ll_get_by_index(ifi->ifi_index);
+	if (n->nlmsg_type == RTM_DELLINK) {
+		if (im)
+			ll_entries_destroy(im);
+		return 0;
+	}
+
+	parse_rtattr_flags(tb, IFLA_MAX, IFLA_RTA(ifi),
+			   IFLA_PAYLOAD(n), NLA_F_NESTED);
+	if (im)
+		ll_entries_update(im, ifi, tb);
+	else
+		ll_entries_create(ifi, tb);
+	return 0;
+}
+
+const char *ll_idx_n2a(unsigned int idx)
+{
+	static char buf[IFNAMSIZ];
+
+	snprintf(buf, sizeof(buf), "if%u", idx);
+	return buf;
+}
+
+static unsigned int ll_idx_a2n(const char *name)
+{
+	unsigned int idx;
+
+	if (sscanf(name, "if%u", &idx) != 1)
+		return 0;
+	return idx;
+}
+
+static int ll_link_get(const char *name, int index)
+{
+	struct {
+		struct nlmsghdr		n;
+		struct ifinfomsg	ifm;
+		char			buf[1024];
+	} req = {
+		.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifinfomsg)),
+		.n.nlmsg_flags = NLM_F_REQUEST,
+		.n.nlmsg_type = RTM_GETLINK,
+		.ifm.ifi_index = index,
+	};
+	__u32 filt_mask = RTEXT_FILTER_VF | RTEXT_FILTER_SKIP_STATS;
+	struct rtnl_handle rth = {};
+	struct nlmsghdr *answer;
+	int rc = 0;
+
+	if (rtnl_open(&rth, 0) < 0)
+		return 0;
+
+	addattr32(&req.n, sizeof(req), IFLA_EXT_MASK, filt_mask);
+	if (name)
+		addattr_l(&req.n, sizeof(req),
+			  !check_ifname(name) ? IFLA_IFNAME : IFLA_ALT_IFNAME,
+			  name, strlen(name) + 1);
+
+	if (rtnl_talk_suppress_rtnl_errmsg(&rth, &req.n, &answer) < 0)
+		goto out;
+
+	/* add entry to cache */
+	rc  = ll_remember_index(answer, NULL);
+	if (!rc) {
+		struct ifinfomsg *ifm = NLMSG_DATA(answer);
+
+		rc = ifm->ifi_index;
+	}
+
+	free(answer);
+out:
+	rtnl_close(&rth);
+	return rc;
+}
+
+const char *ll_index_to_name(unsigned int idx)
+{
+	static char buf[IFNAMSIZ];
+	const struct ll_cache *im;
+
+	if (idx == 0)
+		return "*";
+
+	im = ll_get_by_index(idx);
+	if (im)
+		return im->name;
+
+	if (ll_link_get(NULL, idx) == idx) {
+		im = ll_get_by_index(idx);
+		if (im)
+			return im->name;
+	}
+
+	if (if_indextoname(idx, buf) == NULL)
+		snprintf(buf, IFNAMSIZ, "if%u", idx);
+
+	return buf;
+}
+
+int ll_index_to_type(unsigned idx)
+{
+	const struct ll_cache *im;
+
+	if (idx == 0)
+		return -1;
+
+	im = ll_get_by_index(idx);
+	return im ? im->type : -1;
+}
+
+int ll_index_to_flags(unsigned idx)
+{
+	const struct ll_cache *im;
+
+	if (idx == 0)
+		return 0;
+
+	im = ll_get_by_index(idx);
+	return im ? im->flags : -1;
+}
+
+unsigned ll_name_to_index(const char *name)
+{
+	const struct ll_cache *im;
+	unsigned idx;
+
+	if (name == NULL)
+		return 0;
+
+	im = ll_get_by_name(name);
+	if (im)
+		return im->index;
+
+	idx = ll_link_get(name, 0);
+	if (idx == 0)
+		idx = if_nametoindex(name);
+	if (idx == 0)
+		idx = ll_idx_a2n(name);
+	return idx;
+}
+
+void ll_drop_by_index(unsigned index)
+{
+	struct ll_cache *im;
+
+	im = ll_get_by_index(index);
+	if (!im)
+		return;
+
+	hlist_del(&im->idx_hash);
+	hlist_del(&im->name_hash);
+
+	free(im);
+}
+
+void ll_init_map(struct rtnl_handle *rth)
+{
+	static int initialized;
+
+	if (initialized)
+		return;
+
+	if (rtnl_linkdump_req(rth, AF_UNSPEC) < 0) {
+		perror("Cannot send dump request");
+		exit(1);
+	}
+
+	if (rtnl_dump_filter(rth, ll_remember_index, NULL) < 0) {
+		fprintf(stderr, "Dump terminated\n");
+		exit(1);
+	}
+
+	initialized = 1;
+}
diff --git a/lib/ll_proto.c b/lib/ll_proto.c
new file mode 100644
index 0000000..925e2ca
--- /dev/null
+++ b/lib/ll_proto.c
@@ -0,0 +1,103 @@
+/*
+ * ll_proto.c
+ *
+ *		This program is free software; you can redistribute it and/or
+ *		modify it under the terms of the GNU General Public License
+ *		as published by the Free Software Foundation; either version
+ *		2 of the License, or (at your option) any later version.
+ *
+ * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <string.h>
+
+#include <linux/netdevice.h>
+#include <linux/if_arp.h>
+#include <linux/sockios.h>
+
+#include "utils.h"
+#include "rt_names.h"
+
+
+#define __PF(f,n) { ETH_P_##f, #n },
+
+static const struct proto llproto_names[] = {
+__PF(LOOP,loop)
+__PF(PUP,pup)
+__PF(PUPAT,pupat)
+__PF(IP,ip)
+__PF(X25,x25)
+__PF(ARP,arp)
+__PF(BPQ,bpq)
+__PF(IEEEPUP,ieeepup)
+__PF(IEEEPUPAT,ieeepupat)
+__PF(DEC,dec)
+__PF(DNA_DL,dna_dl)
+__PF(DNA_RC,dna_rc)
+__PF(DNA_RT,dna_rt)
+__PF(LAT,lat)
+__PF(DIAG,diag)
+__PF(CUST,cust)
+__PF(SCA,sca)
+__PF(RARP,rarp)
+__PF(ATALK,atalk)
+__PF(AARP,aarp)
+__PF(IPX,ipx)
+__PF(IPV6,ipv6)
+__PF(PPP_DISC,ppp_disc)
+__PF(PPP_SES,ppp_ses)
+__PF(ATMMPOA,atmmpoa)
+__PF(ATMFATE,atmfate)
+__PF(802_3,802_3)
+__PF(AX25,ax25)
+__PF(ALL,all)
+__PF(802_2,802_2)
+__PF(SNAP,snap)
+__PF(DDCMP,ddcmp)
+__PF(WAN_PPP,wan_ppp)
+__PF(PPP_MP,ppp_mp)
+__PF(LOCALTALK,localtalk)
+__PF(CAN,can)
+__PF(PPPTALK,ppptalk)
+__PF(TR_802_2,tr_802_2)
+__PF(MOBITEX,mobitex)
+__PF(CONTROL,control)
+__PF(IRDA,irda)
+__PF(ECONET,econet)
+__PF(TIPC,tipc)
+__PF(PROFINET,profinet)
+__PF(AOE,aoe)
+__PF(ETHERCAT,ethercat)
+__PF(8021Q,802.1Q)
+__PF(8021AD,802.1ad)
+__PF(MPLS_UC,mpls_uc)
+__PF(MPLS_MC,mpls_mc)
+__PF(TEB,teb)
+
+{ 0x8100, "802.1Q" },
+{ 0x88cc, "LLDP" },
+{ ETH_P_IP, "ipv4" },
+};
+#undef __PF
+
+const char *ll_proto_n2a(unsigned short id, char *buf, int len)
+{
+	size_t len_tb = ARRAY_SIZE(llproto_names);
+
+	return proto_n2a(id, buf, len, llproto_names, len_tb);
+}
+
+int ll_proto_a2n(unsigned short *id, const char *buf)
+{
+	size_t len_tb = ARRAY_SIZE(llproto_names);
+
+	return proto_a2n(id, buf, llproto_names, len_tb);
+}
diff --git a/lib/ll_types.c b/lib/ll_types.c
new file mode 100644
index 0000000..49da15d
--- /dev/null
+++ b/lib/ll_types.c
@@ -0,0 +1,122 @@
+/*
+ * ll_types.c
+ *
+ *		This program is free software; you can redistribute it and/or
+ *		modify it under the terms of the GNU General Public License
+ *		as published by the Free Software Foundation; either version
+ *		2 of the License, or (at your option) any later version.
+ *
+ * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <string.h>
+
+#include <linux/netdevice.h>
+#include <linux/if_arp.h>
+#include <linux/sockios.h>
+
+#include "rt_names.h"
+#include "utils.h"
+
+const char * ll_type_n2a(int type, char *buf, int len)
+{
+#define __PF(f,n) { ARPHRD_##f, #n },
+static const struct {
+	int type;
+	const char *name;
+} arphrd_names[] = {
+__PF(NETROM,netrom)
+__PF(ETHER,ether)
+__PF(EETHER,eether)
+__PF(AX25,ax25)
+__PF(PRONET,pronet)
+__PF(CHAOS,chaos)
+__PF(IEEE802,ieee802)
+__PF(ARCNET,arcnet)
+__PF(APPLETLK,atalk)
+__PF(DLCI,dlci)
+__PF(ATM,atm)
+__PF(METRICOM,metricom)
+__PF(IEEE1394,ieee1394)
+__PF(INFINIBAND,infiniband)
+__PF(SLIP,slip)
+__PF(CSLIP,cslip)
+__PF(SLIP6,slip6)
+__PF(CSLIP6,cslip6)
+__PF(RSRVD,rsrvd)
+__PF(ADAPT,adapt)
+__PF(ROSE,rose)
+__PF(X25,x25)
+__PF(HWX25,hwx25)
+__PF(CAN,can)
+__PF(PPP,ppp)
+__PF(HDLC,hdlc)
+__PF(LAPB,lapb)
+__PF(DDCMP,ddcmp)
+__PF(RAWHDLC,rawhdlc)
+__PF(TUNNEL,ipip)
+__PF(TUNNEL6,tunnel6)
+__PF(FRAD,frad)
+__PF(SKIP,skip)
+__PF(LOOPBACK,loopback)
+__PF(LOCALTLK,ltalk)
+__PF(FDDI,fddi)
+__PF(BIF,bif)
+__PF(SIT,sit)
+__PF(IPDDP,ip/ddp)
+__PF(IPGRE,gre)
+__PF(PIMREG,pimreg)
+__PF(HIPPI,hippi)
+__PF(ASH,ash)
+__PF(ECONET,econet)
+__PF(IRDA,irda)
+__PF(FCPP,fcpp)
+__PF(FCAL,fcal)
+__PF(FCPL,fcpl)
+__PF(FCFABRIC,fcfb0)
+__PF(FCFABRIC+1,fcfb1)
+__PF(FCFABRIC+2,fcfb2)
+__PF(FCFABRIC+3,fcfb3)
+__PF(FCFABRIC+4,fcfb4)
+__PF(FCFABRIC+5,fcfb5)
+__PF(FCFABRIC+6,fcfb6)
+__PF(FCFABRIC+7,fcfb7)
+__PF(FCFABRIC+8,fcfb8)
+__PF(FCFABRIC+9,fcfb9)
+__PF(FCFABRIC+10,fcfb10)
+__PF(FCFABRIC+11,fcfb11)
+__PF(FCFABRIC+12,fcfb12)
+__PF(IEEE802_TR,tr)
+__PF(IEEE80211,ieee802.11)
+__PF(IEEE80211_PRISM,ieee802.11/prism)
+__PF(IEEE80211_RADIOTAP,ieee802.11/radiotap)
+__PF(IEEE802154, ieee802.15.4)
+__PF(IEEE802154_MONITOR, ieee802.15.4/monitor)
+__PF(PHONET, phonet)
+__PF(PHONET_PIPE, phonet_pipe)
+__PF(CAIF, caif)
+__PF(IP6GRE, gre6)
+__PF(NETLINK, netlink)
+__PF(6LOWPAN, 6lowpan)
+
+__PF(NONE, none)
+__PF(VOID,void)
+};
+#undef __PF
+
+        int i;
+        for (i=0; !numeric && i<sizeof(arphrd_names)/sizeof(arphrd_names[0]); i++) {
+                 if (arphrd_names[i].type == type)
+			return arphrd_names[i].name;
+	}
+        snprintf(buf, len, "[%d]", type);
+        return buf;
+}
diff --git a/lib/mnl_utils.c b/lib/mnl_utils.c
new file mode 100644
index 0000000..f8e07d2
--- /dev/null
+++ b/lib/mnl_utils.c
@@ -0,0 +1,254 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * mnl_utils.c	Helpers for working with libmnl.
+ */
+
+#include <errno.h>
+#include <string.h>
+#include <time.h>
+#include <libmnl/libmnl.h>
+#include <linux/genetlink.h>
+
+#include "libnetlink.h"
+#include "mnl_utils.h"
+#include "utils.h"
+
+struct mnl_socket *mnlu_socket_open(int bus)
+{
+	struct mnl_socket *nl;
+	int one = 1;
+
+	nl = mnl_socket_open(bus);
+	if (nl == NULL)
+		return NULL;
+
+	mnl_socket_setsockopt(nl, NETLINK_CAP_ACK, &one, sizeof(one));
+	mnl_socket_setsockopt(nl, NETLINK_EXT_ACK, &one, sizeof(one));
+
+	if (mnl_socket_bind(nl, 0, MNL_SOCKET_AUTOPID) < 0)
+		goto err_bind;
+
+	return nl;
+
+err_bind:
+	mnl_socket_close(nl);
+	return NULL;
+}
+
+struct nlmsghdr *mnlu_msg_prepare(void *buf, uint32_t nlmsg_type, uint16_t flags,
+				  void *extra_header, size_t extra_header_size)
+{
+	struct nlmsghdr *nlh;
+	void *eh;
+
+	nlh = mnl_nlmsg_put_header(buf);
+	nlh->nlmsg_type = nlmsg_type;
+	nlh->nlmsg_flags = flags;
+	nlh->nlmsg_seq = time(NULL);
+
+	eh = mnl_nlmsg_put_extra_header(nlh, extra_header_size);
+	memcpy(eh, extra_header, extra_header_size);
+
+	return nlh;
+}
+
+static int mnlu_cb_noop(const struct nlmsghdr *nlh, void *data)
+{
+	return MNL_CB_OK;
+}
+
+static int mnlu_cb_error(const struct nlmsghdr *nlh, void *data)
+{
+	const struct nlmsgerr *err = mnl_nlmsg_get_payload(nlh);
+
+	/* Netlink subsystems returns the errno value with different signess */
+	if (err->error < 0)
+		errno = -err->error;
+	else
+		errno = err->error;
+
+	if (nl_dump_ext_ack(nlh, NULL))
+		return MNL_CB_ERROR;
+
+	return err->error == 0 ? MNL_CB_STOP : MNL_CB_ERROR;
+}
+
+static int mnlu_cb_stop(const struct nlmsghdr *nlh, void *data)
+{
+	int len = *(int *)NLMSG_DATA(nlh);
+
+	if (len < 0) {
+		errno = -len;
+		nl_dump_ext_ack_done(nlh, sizeof(int), len);
+		return MNL_CB_ERROR;
+	}
+	return MNL_CB_STOP;
+}
+
+static mnl_cb_t mnlu_cb_array[NLMSG_MIN_TYPE] = {
+	[NLMSG_NOOP]	= mnlu_cb_noop,
+	[NLMSG_ERROR]	= mnlu_cb_error,
+	[NLMSG_DONE]	= mnlu_cb_stop,
+	[NLMSG_OVERRUN]	= mnlu_cb_noop,
+};
+
+int mnlu_socket_recv_run(struct mnl_socket *nl, unsigned int seq, void *buf, size_t buf_size,
+			 mnl_cb_t cb, void *data)
+{
+	unsigned int portid = mnl_socket_get_portid(nl);
+	int err;
+
+	do {
+		err = mnl_socket_recvfrom(nl, buf, buf_size);
+		if (err <= 0)
+			break;
+		err = mnl_cb_run2(buf, err, seq, portid,
+				  cb, data, mnlu_cb_array,
+				  ARRAY_SIZE(mnlu_cb_array));
+	} while (err > 0);
+
+	return err;
+}
+
+static int get_family_attrs_cb(const struct nlattr *attr, void *data)
+{
+	int type = mnl_attr_get_type(attr);
+	const struct nlattr **tb = data;
+
+	if (mnl_attr_type_valid(attr, CTRL_ATTR_MAX) < 0)
+		return MNL_CB_ERROR;
+
+	if (type == CTRL_ATTR_FAMILY_ID &&
+	    mnl_attr_validate(attr, MNL_TYPE_U16) < 0)
+		return MNL_CB_ERROR;
+	if (type == CTRL_ATTR_MAXATTR &&
+	    mnl_attr_validate(attr, MNL_TYPE_U32) < 0)
+		return MNL_CB_ERROR;
+	tb[type] = attr;
+	return MNL_CB_OK;
+}
+
+static int get_family_cb(const struct nlmsghdr *nlh, void *data)
+{
+	struct genlmsghdr *genl = mnl_nlmsg_get_payload(nlh);
+	struct nlattr *tb[CTRL_ATTR_MAX + 1] = {};
+	struct mnlu_gen_socket *nlg = data;
+
+	mnl_attr_parse(nlh, sizeof(*genl), get_family_attrs_cb, tb);
+	if (!tb[CTRL_ATTR_FAMILY_ID])
+		return MNL_CB_ERROR;
+	if (!tb[CTRL_ATTR_MAXATTR])
+		return MNL_CB_ERROR;
+	nlg->family = mnl_attr_get_u16(tb[CTRL_ATTR_FAMILY_ID]);
+	nlg->maxattr = mnl_attr_get_u32(tb[CTRL_ATTR_MAXATTR]);
+	return MNL_CB_OK;
+}
+
+static int family_get(struct mnlu_gen_socket *nlg, const char *family_name)
+{
+	struct genlmsghdr hdr = {};
+	struct nlmsghdr *nlh;
+	int err;
+
+	hdr.cmd = CTRL_CMD_GETFAMILY;
+	hdr.version = 0x1;
+
+	nlh = mnlu_msg_prepare(nlg->buf, GENL_ID_CTRL,
+			       NLM_F_REQUEST | NLM_F_ACK,
+			       &hdr, sizeof(hdr));
+
+	mnl_attr_put_strz(nlh, CTRL_ATTR_FAMILY_NAME, family_name);
+
+	err = mnl_socket_sendto(nlg->nl, nlh, nlh->nlmsg_len);
+	if (err < 0)
+		return err;
+
+	err = mnlu_socket_recv_run(nlg->nl, nlh->nlmsg_seq, nlg->buf,
+				   MNL_SOCKET_BUFFER_SIZE,
+				   get_family_cb, nlg);
+	return err;
+}
+
+int mnlu_gen_socket_open(struct mnlu_gen_socket *nlg, const char *family_name,
+			 uint8_t version)
+{
+	int err;
+
+	nlg->buf = malloc(MNL_SOCKET_BUFFER_SIZE);
+	if (!nlg->buf)
+		goto err_buf_alloc;
+
+	nlg->nl = mnlu_socket_open(NETLINK_GENERIC);
+	if (!nlg->nl)
+		goto err_socket_open;
+
+	err = family_get(nlg, family_name);
+	if (err)
+		goto err_socket;
+
+	return 0;
+
+err_socket:
+	mnl_socket_close(nlg->nl);
+err_socket_open:
+	free(nlg->buf);
+err_buf_alloc:
+	return -1;
+}
+
+void mnlu_gen_socket_close(struct mnlu_gen_socket *nlg)
+{
+	mnl_socket_close(nlg->nl);
+	free(nlg->buf);
+}
+
+struct nlmsghdr *
+_mnlu_gen_socket_cmd_prepare(struct mnlu_gen_socket *nlg,
+			     uint8_t cmd, uint16_t flags,
+			     uint32_t id, uint8_t version)
+{
+	struct genlmsghdr hdr = {};
+	struct nlmsghdr *nlh;
+
+	hdr.cmd = cmd;
+	hdr.version = version;
+	nlh = mnlu_msg_prepare(nlg->buf, id, flags, &hdr, sizeof(hdr));
+	nlg->seq = nlh->nlmsg_seq;
+	return nlh;
+}
+
+struct nlmsghdr *mnlu_gen_socket_cmd_prepare(struct mnlu_gen_socket *nlg,
+					     uint8_t cmd, uint16_t flags)
+{
+	return _mnlu_gen_socket_cmd_prepare(nlg, cmd, flags, nlg->family,
+					    nlg->version);
+}
+
+int mnlu_gen_socket_sndrcv(struct mnlu_gen_socket *nlg, const struct nlmsghdr *nlh,
+			   mnl_cb_t data_cb, void *data)
+{
+	int err;
+
+	err = mnl_socket_sendto(nlg->nl, nlh, nlh->nlmsg_len);
+	if (err < 0) {
+		perror("Failed to send data");
+		return -errno;
+	}
+
+	err = mnlu_socket_recv_run(nlg->nl, nlh->nlmsg_seq, nlg->buf,
+				   MNL_SOCKET_BUFFER_SIZE,
+				   data_cb, data);
+	if (err < 0) {
+		fprintf(stderr, "kernel answers: %s\n", strerror(errno));
+		return -errno;
+	}
+	return 0;
+}
+
+int mnlu_gen_socket_recv_run(struct mnlu_gen_socket *nlg, mnl_cb_t cb,
+			     void *data)
+{
+	return mnlu_socket_recv_run(nlg->nl, nlg->seq, nlg->buf,
+				    MNL_SOCKET_BUFFER_SIZE,
+				    cb, data);
+}
diff --git a/lib/mpls_ntop.c b/lib/mpls_ntop.c
new file mode 100644
index 0000000..f8d89f4
--- /dev/null
+++ b/lib/mpls_ntop.c
@@ -0,0 +1,52 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#include <errno.h>
+#include <string.h>
+#include <sys/types.h>
+#include <netinet/in.h>
+#include <linux/mpls.h>
+
+#include "utils.h"
+
+static const char *mpls_ntop1(const struct mpls_label *addr, char *buf, size_t buflen)
+{
+	size_t destlen = buflen;
+	char *dest = buf;
+	int count = 0;
+
+	while (1) {
+		uint32_t entry = ntohl(addr[count++].entry);
+		uint32_t label = (entry & MPLS_LS_LABEL_MASK) >> MPLS_LS_LABEL_SHIFT;
+		int len = snprintf(dest, destlen, "%u", label);
+
+		if (len >= destlen)
+			break;
+
+		/* Is this the end? */
+		if (entry & MPLS_LS_S_MASK)
+			return buf;
+
+		dest += len;
+		destlen -= len;
+		if (destlen) {
+			*dest = '/';
+			dest++;
+			destlen--;
+		}
+	}
+	errno = -E2BIG;
+	return NULL;
+}
+
+const char *mpls_ntop(int af, const void *addr, char *buf, size_t buflen)
+{
+	switch(af) {
+	case AF_MPLS:
+		errno = 0;
+		return mpls_ntop1((struct mpls_label *)addr, buf, buflen);
+	default:
+		errno = EAFNOSUPPORT;
+	}
+
+	return NULL;
+}
diff --git a/lib/mpls_pton.c b/lib/mpls_pton.c
new file mode 100644
index 0000000..065374e
--- /dev/null
+++ b/lib/mpls_pton.c
@@ -0,0 +1,63 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#include <errno.h>
+#include <string.h>
+#include <sys/types.h>
+#include <netinet/in.h>
+#include <linux/mpls.h>
+
+#include "utils.h"
+
+
+static int mpls_pton1(const char *name, struct mpls_label *addr,
+		      unsigned int maxlabels)
+{
+	char *endp;
+	unsigned count;
+
+	for (count = 0; count < maxlabels; count++) {
+		unsigned long label;
+
+		label = strtoul(name, &endp, 0);
+		/* Fail when the label value is out or range */
+		if (label >= (1 << 20))
+			return 0;
+
+		if (endp == name) /* no digits */
+			return 0;
+
+		addr->entry = htonl(label << MPLS_LS_LABEL_SHIFT);
+		if (*endp == '\0') {
+			addr->entry |= htonl(1 << MPLS_LS_S_SHIFT);
+			return 1;
+		}
+
+		/* Bad character in the address */
+		if (*endp != '/')
+			return 0;
+
+		name = endp + 1;
+		addr += 1;
+	}
+	/* The address was too long */
+	fprintf(stderr, "Error: too many labels.\n");
+	return 0;
+}
+
+int mpls_pton(int af, const char *src, void *addr, size_t alen)
+{
+	unsigned int maxlabels = alen / sizeof(struct mpls_label);
+	int err;
+
+	switch(af) {
+	case AF_MPLS:
+		errno = 0;
+		err = mpls_pton1(src, (struct mpls_label *)addr, maxlabels);
+		break;
+	default:
+		errno = EAFNOSUPPORT;
+		err = -1;
+	}
+
+	return err;
+}
diff --git a/lib/names.c b/lib/names.c
new file mode 100644
index 0000000..b46ea79
--- /dev/null
+++ b/lib/names.c
@@ -0,0 +1,152 @@
+/*
+ * names.c		db names
+ *
+ *		This program is free software; you can redistribute it and/or
+ *		modify it under the terms of the GNU General Public License
+ *		as published by the Free Software Foundation; either version
+ *		2 of the License, or (at your option) any later version.
+ *
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <errno.h>
+
+#include "names.h"
+#include "utils.h"
+
+#define MAX_ENTRIES  256
+#define NAME_MAX_LEN 512
+
+static int read_id_name(FILE *fp, int *id, char *name)
+{
+	char buf[NAME_MAX_LEN];
+	int min, maj;
+
+	while (fgets(buf, sizeof(buf), fp)) {
+		char *p = buf;
+
+		while (*p == ' ' || *p == '\t')
+			p++;
+
+		if (*p == '#' || *p == '\n' || *p == 0)
+			continue;
+
+		if (sscanf(p, "%x:%x %s\n", &maj, &min, name) == 3) {
+			*id = (maj << 16) | min;
+		} else if (sscanf(p, "%x:%x %s #", &maj, &min, name) == 3) {
+			*id = (maj << 16) | min;
+		} else if (sscanf(p, "0x%x %s\n", id, name) != 2 &&
+				sscanf(p, "0x%x %s #", id, name) != 2 &&
+				sscanf(p, "%d %s\n", id, name) != 2 &&
+				sscanf(p, "%d %s #", id, name) != 2) {
+			strcpy(name, p);
+			return -1;
+		}
+		return 1;
+	}
+
+	return 0;
+}
+
+struct db_names *db_names_alloc(void)
+{
+	struct db_names *db;
+
+	db = calloc(1, sizeof(*db));
+	if (!db)
+		return NULL;
+
+	db->size = MAX_ENTRIES;
+	db->hash = calloc(db->size, sizeof(struct db_entry *));
+
+	return db;
+}
+
+int db_names_load(struct db_names *db, const char *path)
+{
+	struct db_entry *entry;
+	FILE *fp;
+	int id;
+	char namebuf[NAME_MAX_LEN] = {0};
+	int ret = -1;
+
+	fp = fopen(path, "r");
+	if (!fp)
+		return -ENOENT;
+
+	while ((ret = read_id_name(fp, &id, &namebuf[0]))) {
+		if (ret == -1) {
+			fprintf(stderr, "Database %s is corrupted at %s\n",
+					path, namebuf);
+			goto Exit;
+		}
+		ret = -1;
+
+		if (id < 0)
+			continue;
+
+		entry = malloc(sizeof(*entry));
+		if (!entry)
+			goto Exit;
+
+		entry->name = strdup(namebuf);
+		if (!entry->name) {
+			free(entry);
+			goto Exit;
+		}
+
+		entry->id   = id;
+		entry->next = db->hash[id & (db->size - 1)];
+		db->hash[id & (db->size - 1)] = entry;
+	}
+	ret = 0;
+
+Exit:
+	fclose(fp);
+	return ret;
+}
+
+void db_names_free(struct db_names *db)
+{
+	int i;
+
+	if (!db)
+		return;
+
+	for (i = 0; i < db->size; i++) {
+		struct db_entry *entry = db->hash[i];
+
+		while (entry) {
+			struct db_entry *next = entry->next;
+
+			free(entry->name);
+			free(entry);
+			entry = next;
+		}
+	}
+
+	free(db->hash);
+	free(db);
+}
+
+char *id_to_name(struct db_names *db, int id, char *name)
+{
+	struct db_entry *entry;
+
+	if (!db)
+		return NULL;
+
+	entry = db->hash[id & (db->size - 1)];
+	while (entry && entry->id != id)
+		entry = entry->next;
+
+	if (entry) {
+		strncpy(name, entry->name, IDNAME_MAX);
+		return name;
+	}
+
+	snprintf(name, IDNAME_MAX, "%d", id);
+	return NULL;
+}
diff --git a/lib/namespace.c b/lib/namespace.c
new file mode 100644
index 0000000..45a7ded
--- /dev/null
+++ b/lib/namespace.c
@@ -0,0 +1,145 @@
+/*
+ * namespace.c
+ *
+ *		This program is free software; you can redistribute it and/or
+ *		modify it under the terms of the GNU General Public License
+ *		as published by the Free Software Foundation; either version
+ *		2 of the License, or (at your option) any later version.
+ */
+
+#include <sys/statvfs.h>
+#include <fcntl.h>
+#include <dirent.h>
+#include <limits.h>
+
+#include "utils.h"
+#include "namespace.h"
+
+static void bind_etc(const char *name)
+{
+	char etc_netns_path[sizeof(NETNS_ETC_DIR) + NAME_MAX];
+	char netns_name[PATH_MAX];
+	char etc_name[PATH_MAX];
+	struct dirent *entry;
+	DIR *dir;
+
+	if (strlen(name) >= NAME_MAX)
+		return;
+
+	snprintf(etc_netns_path, sizeof(etc_netns_path), "%s/%s", NETNS_ETC_DIR, name);
+	dir = opendir(etc_netns_path);
+	if (!dir)
+		return;
+
+	while ((entry = readdir(dir)) != NULL) {
+		if (strcmp(entry->d_name, ".") == 0)
+			continue;
+		if (strcmp(entry->d_name, "..") == 0)
+			continue;
+		snprintf(netns_name, sizeof(netns_name), "%s/%s", etc_netns_path, entry->d_name);
+		snprintf(etc_name, sizeof(etc_name), "/etc/%s", entry->d_name);
+		if (mount(netns_name, etc_name, "none", MS_BIND, NULL) < 0) {
+			fprintf(stderr, "Bind %s -> %s failed: %s\n",
+				netns_name, etc_name, strerror(errno));
+		}
+	}
+	closedir(dir);
+}
+
+int netns_switch(char *name)
+{
+	char net_path[PATH_MAX];
+	int netns;
+	unsigned long mountflags = 0;
+	struct statvfs fsstat;
+
+	snprintf(net_path, sizeof(net_path), "%s/%s", NETNS_RUN_DIR, name);
+	netns = open(net_path, O_RDONLY | O_CLOEXEC);
+	if (netns < 0) {
+		fprintf(stderr, "Cannot open network namespace \"%s\": %s\n",
+			name, strerror(errno));
+		return -1;
+	}
+
+	if (setns(netns, CLONE_NEWNET) < 0) {
+		fprintf(stderr, "setting the network namespace \"%s\" failed: %s\n",
+			name, strerror(errno));
+		close(netns);
+		return -1;
+	}
+	close(netns);
+
+	if (unshare(CLONE_NEWNS) < 0) {
+		fprintf(stderr, "unshare failed: %s\n", strerror(errno));
+		return -1;
+	}
+	/* Don't let any mounts propagate back to the parent */
+	if (mount("", "/", "none", MS_SLAVE | MS_REC, NULL)) {
+		fprintf(stderr, "\"mount --make-rslave /\" failed: %s\n",
+			strerror(errno));
+		return -1;
+	}
+
+	/* Mount a version of /sys that describes the network namespace */
+
+	if (umount2("/sys", MNT_DETACH) < 0) {
+		/* If this fails, perhaps there wasn't a sysfs instance mounted. Good. */
+		if (statvfs("/sys", &fsstat) == 0) {
+			/* We couldn't umount the sysfs, we'll attempt to overlay it.
+			 * A read-only instance can't be shadowed with a read-write one. */
+			if (fsstat.f_flag & ST_RDONLY)
+				mountflags = MS_RDONLY;
+		}
+	}
+	if (mount(name, "/sys", "sysfs", mountflags, NULL) < 0) {
+		fprintf(stderr, "mount of /sys failed: %s\n",strerror(errno));
+		return -1;
+	}
+
+	/* Setup bind mounts for config files in /etc */
+	bind_etc(name);
+	return 0;
+}
+
+int netns_get_fd(const char *name)
+{
+	char pathbuf[PATH_MAX];
+	const char *path, *ptr;
+
+	path = name;
+	ptr = strchr(name, '/');
+	if (!ptr) {
+		snprintf(pathbuf, sizeof(pathbuf), "%s/%s",
+			NETNS_RUN_DIR, name );
+		path = pathbuf;
+	}
+	return open(path, O_RDONLY);
+}
+
+int netns_foreach(int (*func)(char *nsname, void *arg), void *arg)
+{
+	DIR *dir;
+	struct dirent *entry;
+
+	dir = opendir(NETNS_RUN_DIR);
+	if (!dir) {
+		if (errno == ENOENT)
+			return 0;
+
+		fprintf(stderr, "Failed to open directory %s: %s\n",
+			NETNS_RUN_DIR, strerror(errno));
+		return -1;
+	}
+
+	while ((entry = readdir(dir)) != NULL) {
+		if (strcmp(entry->d_name, ".") == 0)
+			continue;
+		if (strcmp(entry->d_name, "..") == 0)
+			continue;
+		if (func(entry->d_name, arg))
+			break;
+	}
+
+	closedir(dir);
+	return 0;
+}
diff --git a/lib/netrom_ntop.c b/lib/netrom_ntop.c
new file mode 100644
index 0000000..3dd6cb0
--- /dev/null
+++ b/lib/netrom_ntop.c
@@ -0,0 +1,23 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#include <sys/socket.h>
+#include <errno.h>
+#include <linux/ax25.h>
+
+#include "utils.h"
+
+const char *ax25_ntop1(const ax25_address *src, char *dst, socklen_t size);
+
+const char *netrom_ntop(int af, const void *addr, char *buf, socklen_t buflen)
+{
+	switch (af) {
+	case AF_NETROM:
+		errno = 0;
+		return ax25_ntop1((ax25_address *)addr, buf, buflen);
+
+	default:
+		errno = EAFNOSUPPORT;
+	}
+
+	return NULL;
+}
diff --git a/lib/ppp_proto.c b/lib/ppp_proto.c
new file mode 100644
index 0000000..a634664
--- /dev/null
+++ b/lib/ppp_proto.c
@@ -0,0 +1,52 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Utilities for translating PPP protocols from strings
+ * and vice versa.
+ *
+ * Authors:     Wojciech Drewek <wojciech.drewek@intel.com>
+ */
+
+#include <linux/ppp_defs.h>
+#include <linux/if_ether.h>
+#include "utils.h"
+#include "rt_names.h"
+
+static const struct proto ppp_proto_names[] = {
+	{PPP_IP, "ip"},
+	{PPP_AT, "at"},
+	{PPP_IPX, "ipx"},
+	{PPP_VJC_COMP, "vjc_comp"},
+	{PPP_VJC_UNCOMP, "vjc_uncomp"},
+	{PPP_MP, "mp"},
+	{PPP_IPV6, "ipv6"},
+	{PPP_COMPFRAG, "compfrag"},
+	{PPP_COMP, "comp"},
+	{PPP_MPLS_UC, "mpls_uc"},
+	{PPP_MPLS_MC, "mpls_mc"},
+	{PPP_IPCP, "ipcp"},
+	{PPP_ATCP, "atcp"},
+	{PPP_IPXCP, "ipxcp"},
+	{PPP_IPV6CP, "ipv6cp"},
+	{PPP_CCPFRAG, "ccpfrag"},
+	{PPP_CCP, "ccp"},
+	{PPP_MPLSCP, "mplscp"},
+	{PPP_LCP, "lcp"},
+	{PPP_PAP, "pap"},
+	{PPP_LQR, "lqr"},
+	{PPP_CHAP, "chap"},
+	{PPP_CBCP, "cbcp"},
+};
+
+const char *ppp_proto_n2a(unsigned short id, char *buf, int len)
+{
+	size_t len_tb = ARRAY_SIZE(ppp_proto_names);
+
+	return proto_n2a(id, buf, len, ppp_proto_names, len_tb);
+}
+
+int ppp_proto_a2n(unsigned short *id, const char *buf)
+{
+	size_t len_tb = ARRAY_SIZE(ppp_proto_names);
+
+	return proto_a2n(id, buf, ppp_proto_names, len_tb);
+}
diff --git a/lib/rose_ntop.c b/lib/rose_ntop.c
new file mode 100644
index 0000000..c9ba712
--- /dev/null
+++ b/lib/rose_ntop.c
@@ -0,0 +1,56 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <string.h>
+#include <errno.h>
+
+#include <linux/netdevice.h>
+#include <linux/if_arp.h>
+#include <linux/sockios.h>
+#include <linux/rose.h>
+
+#include "rt_names.h"
+#include "utils.h"
+
+static const char *rose_ntop1(const rose_address *src, char *dst,
+			      socklen_t size)
+{
+	char *p = dst;
+	int i;
+
+	if (size < 10)
+		return NULL;
+
+	for (i = 0; i < 5; i++) {
+		*p++ = '0' + ((src->rose_addr[i] >> 4) & 0xf);
+		*p++ = '0' + ((src->rose_addr[i]     ) & 0xf);
+	}
+
+	if (size == 10)
+		return dst;
+
+	*p = '\0';
+
+	return dst;
+}
+
+const char *rose_ntop(int af, const void *addr, char *buf, socklen_t buflen)
+{
+	switch (af) {
+	case AF_ROSE:
+		errno = 0;
+		return rose_ntop1((rose_address *)addr, buf, buflen);
+
+	default:
+		errno = EAFNOSUPPORT;
+	}
+
+	return NULL;
+}
diff --git a/lib/rt_names.c b/lib/rt_names.c
new file mode 100644
index 0000000..b976471
--- /dev/null
+++ b/lib/rt_names.c
@@ -0,0 +1,788 @@
+/*
+ * rt_names.c		rtnetlink names DB.
+ *
+ *		This program is free software; you can redistribute it and/or
+ *		modify it under the terms of the GNU General Public License
+ *		as published by the Free Software Foundation; either version
+ *		2 of the License, or (at your option) any later version.
+ *
+ * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <string.h>
+#include <sys/time.h>
+#include <sys/socket.h>
+#include <dirent.h>
+#include <limits.h>
+
+#include <asm/types.h>
+#include <linux/rtnetlink.h>
+
+#include "rt_names.h"
+#include "utils.h"
+
+#define NAME_MAX_LEN 512
+
+int numeric;
+
+struct rtnl_hash_entry {
+	struct rtnl_hash_entry	*next;
+	const char		*name;
+	unsigned int		id;
+};
+
+static int fread_id_name(FILE *fp, int *id, char *namebuf)
+{
+	char buf[NAME_MAX_LEN];
+
+	while (fgets(buf, sizeof(buf), fp)) {
+		char *p = buf;
+
+		while (*p == ' ' || *p == '\t')
+			p++;
+
+		if (*p == '#' || *p == '\n' || *p == 0)
+			continue;
+
+		if (sscanf(p, "0x%x %s\n", id, namebuf) != 2 &&
+				sscanf(p, "0x%x %s #", id, namebuf) != 2 &&
+				sscanf(p, "%d %s\n", id, namebuf) != 2 &&
+				sscanf(p, "%d %s #", id, namebuf) != 2) {
+			strcpy(namebuf, p);
+			return -1;
+		}
+		return 1;
+	}
+	return 0;
+}
+
+static void
+rtnl_hash_initialize(const char *file, struct rtnl_hash_entry **hash, int size)
+{
+	struct rtnl_hash_entry *entry;
+	FILE *fp;
+	int id;
+	char namebuf[NAME_MAX_LEN] = {0};
+	int ret;
+
+	fp = fopen(file, "r");
+	if (!fp)
+		return;
+
+	while ((ret = fread_id_name(fp, &id, &namebuf[0]))) {
+		if (ret == -1) {
+			fprintf(stderr, "Database %s is corrupted at %s\n",
+					file, namebuf);
+			fclose(fp);
+			return;
+		}
+
+		if (id < 0)
+			continue;
+
+		entry = malloc(sizeof(*entry));
+		entry->id   = id;
+		entry->name = strdup(namebuf);
+		entry->next = hash[id & (size - 1)];
+		hash[id & (size - 1)] = entry;
+	}
+	fclose(fp);
+}
+
+static void rtnl_tab_initialize(const char *file, char **tab, int size)
+{
+	FILE *fp;
+	int id;
+	char namebuf[NAME_MAX_LEN] = {0};
+	int ret;
+
+	fp = fopen(file, "r");
+	if (!fp)
+		return;
+
+	while ((ret = fread_id_name(fp, &id, &namebuf[0]))) {
+		if (ret == -1) {
+			fprintf(stderr, "Database %s is corrupted at %s\n",
+					file, namebuf);
+			fclose(fp);
+			return;
+		}
+		if (id < 0 || id > size)
+			continue;
+
+		tab[id] = strdup(namebuf);
+	}
+	fclose(fp);
+}
+
+static char *rtnl_rtprot_tab[256] = {
+	[RTPROT_UNSPEC]	    = "unspec",
+	[RTPROT_REDIRECT]   = "redirect",
+	[RTPROT_KERNEL]	    = "kernel",
+	[RTPROT_BOOT]	    = "boot",
+	[RTPROT_STATIC]	    = "static",
+
+	[RTPROT_GATED]	    = "gated",
+	[RTPROT_RA]	    = "ra",
+	[RTPROT_MRT]	    = "mrt",
+	[RTPROT_ZEBRA]	    = "zebra",
+	[RTPROT_BIRD]	    = "bird",
+	[RTPROT_BABEL]	    = "babel",
+	[RTPROT_DNROUTED]   = "dnrouted",
+	[RTPROT_XORP]	    = "xorp",
+	[RTPROT_NTK]	    = "ntk",
+	[RTPROT_DHCP]	    = "dhcp",
+	[RTPROT_KEEPALIVED] = "keepalived",
+	[RTPROT_BGP]	    = "bgp",
+	[RTPROT_ISIS]	    = "isis",
+	[RTPROT_OSPF]	    = "ospf",
+	[RTPROT_RIP]	    = "rip",
+	[RTPROT_EIGRP]	    = "eigrp",
+};
+
+
+static int rtnl_rtprot_init;
+
+static void rtnl_rtprot_initialize(void)
+{
+	struct dirent *de;
+	DIR *d;
+
+	rtnl_rtprot_init = 1;
+	rtnl_tab_initialize(CONFDIR "/rt_protos",
+			    rtnl_rtprot_tab, 256);
+
+	d = opendir(CONFDIR "/rt_protos.d");
+	if (!d)
+		return;
+
+	while ((de = readdir(d)) != NULL) {
+		char path[PATH_MAX];
+		size_t len;
+
+		if (*de->d_name == '.')
+			continue;
+
+		/* only consider filenames ending in '.conf' */
+		len = strlen(de->d_name);
+		if (len <= 5)
+			continue;
+		if (strcmp(de->d_name + len - 5, ".conf"))
+			continue;
+
+		snprintf(path, sizeof(path), CONFDIR "/rt_protos.d/%s",
+			 de->d_name);
+		rtnl_tab_initialize(path, rtnl_rtprot_tab, 256);
+	}
+	closedir(d);
+}
+
+const char *rtnl_rtprot_n2a(int id, char *buf, int len)
+{
+	if (id < 0 || id >= 256 || numeric) {
+		snprintf(buf, len, "%u", id);
+		return buf;
+	}
+	if (!rtnl_rtprot_tab[id]) {
+		if (!rtnl_rtprot_init)
+			rtnl_rtprot_initialize();
+	}
+	if (rtnl_rtprot_tab[id])
+		return rtnl_rtprot_tab[id];
+	snprintf(buf, len, "%u", id);
+	return buf;
+}
+
+int rtnl_rtprot_a2n(__u32 *id, const char *arg)
+{
+	static char *cache;
+	static unsigned long res;
+	char *end;
+	int i;
+
+	if (cache && strcmp(cache, arg) == 0) {
+		*id = res;
+		return 0;
+	}
+
+	if (!rtnl_rtprot_init)
+		rtnl_rtprot_initialize();
+
+	for (i = 0; i < 256; i++) {
+		if (rtnl_rtprot_tab[i] &&
+		    strcmp(rtnl_rtprot_tab[i], arg) == 0) {
+			cache = rtnl_rtprot_tab[i];
+			res = i;
+			*id = res;
+			return 0;
+		}
+	}
+
+	res = strtoul(arg, &end, 0);
+	if (!end || end == arg || *end || res > 255)
+		return -1;
+	*id = res;
+	return 0;
+}
+
+
+static char *rtnl_rtscope_tab[256] = {
+	[RT_SCOPE_UNIVERSE]	= "global",
+	[RT_SCOPE_NOWHERE]	= "nowhere",
+	[RT_SCOPE_HOST]		= "host",
+	[RT_SCOPE_LINK]		= "link",
+	[RT_SCOPE_SITE]		= "site",
+};
+
+static int rtnl_rtscope_init;
+
+static void rtnl_rtscope_initialize(void)
+{
+	rtnl_rtscope_init = 1;
+	rtnl_tab_initialize(CONFDIR "/rt_scopes",
+			    rtnl_rtscope_tab, 256);
+}
+
+const char *rtnl_rtscope_n2a(int id, char *buf, int len)
+{
+	if (id < 0 || id >= 256 || numeric) {
+		snprintf(buf, len, "%d", id);
+		return buf;
+	}
+
+	if (!rtnl_rtscope_tab[id]) {
+		if (!rtnl_rtscope_init)
+			rtnl_rtscope_initialize();
+	}
+
+	if (rtnl_rtscope_tab[id])
+		return rtnl_rtscope_tab[id];
+
+	snprintf(buf, len, "%d", id);
+	return buf;
+}
+
+int rtnl_rtscope_a2n(__u32 *id, const char *arg)
+{
+	static const char *cache;
+	static unsigned long res;
+	char *end;
+	int i;
+
+	if (cache && strcmp(cache, arg) == 0) {
+		*id = res;
+		return 0;
+	}
+
+	if (!rtnl_rtscope_init)
+		rtnl_rtscope_initialize();
+
+	for (i = 0; i < 256; i++) {
+		if (rtnl_rtscope_tab[i] &&
+		    strcmp(rtnl_rtscope_tab[i], arg) == 0) {
+			cache = rtnl_rtscope_tab[i];
+			res = i;
+			*id = res;
+			return 0;
+		}
+	}
+
+	res = strtoul(arg, &end, 0);
+	if (!end || end == arg || *end || res > 255)
+		return -1;
+	*id = res;
+	return 0;
+}
+
+
+static char *rtnl_rtrealm_tab[256] = {
+	"unknown",
+};
+
+static int rtnl_rtrealm_init;
+
+static void rtnl_rtrealm_initialize(void)
+{
+	rtnl_rtrealm_init = 1;
+	rtnl_tab_initialize(CONFDIR "/rt_realms",
+			    rtnl_rtrealm_tab, 256);
+}
+
+const char *rtnl_rtrealm_n2a(int id, char *buf, int len)
+{
+	if (id < 0 || id >= 256 || numeric) {
+		snprintf(buf, len, "%d", id);
+		return buf;
+	}
+	if (!rtnl_rtrealm_tab[id]) {
+		if (!rtnl_rtrealm_init)
+			rtnl_rtrealm_initialize();
+	}
+	if (rtnl_rtrealm_tab[id])
+		return rtnl_rtrealm_tab[id];
+	snprintf(buf, len, "%d", id);
+	return buf;
+}
+
+
+int rtnl_rtrealm_a2n(__u32 *id, const char *arg)
+{
+	static char *cache;
+	static unsigned long res;
+	char *end;
+	int i;
+
+	if (cache && strcmp(cache, arg) == 0) {
+		*id = res;
+		return 0;
+	}
+
+	if (!rtnl_rtrealm_init)
+		rtnl_rtrealm_initialize();
+
+	for (i = 0; i < 256; i++) {
+		if (rtnl_rtrealm_tab[i] &&
+		    strcmp(rtnl_rtrealm_tab[i], arg) == 0) {
+			cache = rtnl_rtrealm_tab[i];
+			res = i;
+			*id = res;
+			return 0;
+		}
+	}
+
+	res = strtoul(arg, &end, 0);
+	if (!end || end == arg || *end || res > 255)
+		return -1;
+	*id = res;
+	return 0;
+}
+
+
+static struct rtnl_hash_entry dflt_table_entry  = { .name = "default" };
+static struct rtnl_hash_entry main_table_entry  = { .name = "main" };
+static struct rtnl_hash_entry local_table_entry = { .name = "local" };
+
+static struct rtnl_hash_entry *rtnl_rttable_hash[256] = {
+	[RT_TABLE_DEFAULT] = &dflt_table_entry,
+	[RT_TABLE_MAIN]    = &main_table_entry,
+	[RT_TABLE_LOCAL]   = &local_table_entry,
+};
+
+static int rtnl_rttable_init;
+
+static void rtnl_rttable_initialize(void)
+{
+	struct dirent *de;
+	DIR *d;
+	int i;
+
+	rtnl_rttable_init = 1;
+	for (i = 0; i < 256; i++) {
+		if (rtnl_rttable_hash[i])
+			rtnl_rttable_hash[i]->id = i;
+	}
+	rtnl_hash_initialize(CONFDIR "/rt_tables",
+			     rtnl_rttable_hash, 256);
+
+	d = opendir(CONFDIR "/rt_tables.d");
+	if (!d)
+		return;
+
+	while ((de = readdir(d)) != NULL) {
+		char path[PATH_MAX];
+		size_t len;
+
+		if (*de->d_name == '.')
+			continue;
+
+		/* only consider filenames ending in '.conf' */
+		len = strlen(de->d_name);
+		if (len <= 5)
+			continue;
+		if (strcmp(de->d_name + len - 5, ".conf"))
+			continue;
+
+		snprintf(path, sizeof(path),
+			 CONFDIR "/rt_tables.d/%s", de->d_name);
+		rtnl_hash_initialize(path, rtnl_rttable_hash, 256);
+	}
+	closedir(d);
+}
+
+const char *rtnl_rttable_n2a(__u32 id, char *buf, int len)
+{
+	struct rtnl_hash_entry *entry;
+
+	if (!rtnl_rttable_init)
+		rtnl_rttable_initialize();
+	entry = rtnl_rttable_hash[id & 255];
+	while (entry && entry->id != id)
+		entry = entry->next;
+	if (!numeric && entry)
+		return entry->name;
+	snprintf(buf, len, "%u", id);
+	return buf;
+}
+
+int rtnl_rttable_a2n(__u32 *id, const char *arg)
+{
+	static const char *cache;
+	static unsigned long res;
+	struct rtnl_hash_entry *entry;
+	char *end;
+	unsigned long i;
+
+	if (cache && strcmp(cache, arg) == 0) {
+		*id = res;
+		return 0;
+	}
+
+	if (!rtnl_rttable_init)
+		rtnl_rttable_initialize();
+
+	for (i = 0; i < 256; i++) {
+		entry = rtnl_rttable_hash[i];
+		while (entry && strcmp(entry->name, arg))
+			entry = entry->next;
+		if (entry) {
+			cache = entry->name;
+			res = entry->id;
+			*id = res;
+			return 0;
+		}
+	}
+
+	i = strtoul(arg, &end, 0);
+	if (!end || end == arg || *end || i > RT_TABLE_MAX)
+		return -1;
+	*id = i;
+	return 0;
+}
+
+
+static char *rtnl_rtdsfield_tab[256] = {
+	"0",
+};
+
+static int rtnl_rtdsfield_init;
+
+static void rtnl_rtdsfield_initialize(void)
+{
+	rtnl_rtdsfield_init = 1;
+	rtnl_tab_initialize(CONFDIR "/rt_dsfield",
+			    rtnl_rtdsfield_tab, 256);
+}
+
+const char *rtnl_dsfield_n2a(int id, char *buf, int len)
+{
+	const char *name;
+
+	if (id < 0 || id >= 256) {
+		snprintf(buf, len, "%d", id);
+		return buf;
+	}
+	if (!numeric) {
+		name = rtnl_dsfield_get_name(id);
+		if (name != NULL)
+			return name;
+	}
+	snprintf(buf, len, "0x%02x", id);
+	return buf;
+}
+
+const char *rtnl_dsfield_get_name(int id)
+{
+	if (id < 0 || id >= 256)
+		return NULL;
+	if (!rtnl_rtdsfield_tab[id]) {
+		if (!rtnl_rtdsfield_init)
+			rtnl_rtdsfield_initialize();
+	}
+	return rtnl_rtdsfield_tab[id];
+}
+
+
+int rtnl_dsfield_a2n(__u32 *id, const char *arg)
+{
+	static char *cache;
+	static unsigned long res;
+	char *end;
+	int i;
+
+	if (cache && strcmp(cache, arg) == 0) {
+		*id = res;
+		return 0;
+	}
+
+	if (!rtnl_rtdsfield_init)
+		rtnl_rtdsfield_initialize();
+
+	for (i = 0; i < 256; i++) {
+		if (rtnl_rtdsfield_tab[i] &&
+		    strcmp(rtnl_rtdsfield_tab[i], arg) == 0) {
+			cache = rtnl_rtdsfield_tab[i];
+			res = i;
+			*id = res;
+			return 0;
+		}
+	}
+
+	res = strtoul(arg, &end, 16);
+	if (!end || end == arg || *end || res > 255)
+		return -1;
+	*id = res;
+	return 0;
+}
+
+
+static struct rtnl_hash_entry dflt_group_entry = {
+	.id = 0, .name = "default"
+};
+
+static struct rtnl_hash_entry *rtnl_group_hash[256] = {
+	[0] = &dflt_group_entry,
+};
+
+static int rtnl_group_init;
+
+static void rtnl_group_initialize(void)
+{
+	rtnl_group_init = 1;
+	rtnl_hash_initialize(CONFDIR "/group",
+			     rtnl_group_hash, 256);
+}
+
+int rtnl_group_a2n(int *id, const char *arg)
+{
+	static const char *cache;
+	static unsigned long res;
+	struct rtnl_hash_entry *entry;
+	char *end;
+	int i;
+
+	if (cache && strcmp(cache, arg) == 0) {
+		*id = res;
+		return 0;
+	}
+
+	if (!rtnl_group_init)
+		rtnl_group_initialize();
+
+	for (i = 0; i < 256; i++) {
+		entry = rtnl_group_hash[i];
+		while (entry && strcmp(entry->name, arg))
+			entry = entry->next;
+		if (entry) {
+			cache = entry->name;
+			res = entry->id;
+			*id = res;
+			return 0;
+		}
+	}
+
+	i = strtol(arg, &end, 0);
+	if (!end || end == arg || *end || i < 0)
+		return -1;
+	*id = i;
+	return 0;
+}
+
+const char *rtnl_group_n2a(int id, char *buf, int len)
+{
+	struct rtnl_hash_entry *entry;
+	int i;
+
+	if (!rtnl_group_init)
+		rtnl_group_initialize();
+
+	for (i = 0; !numeric && i < 256; i++) {
+		entry = rtnl_group_hash[i];
+
+		while (entry) {
+			if (entry->id == id)
+				return entry->name;
+			entry = entry->next;
+		}
+	}
+
+	snprintf(buf, len, "%d", id);
+	return buf;
+}
+
+static char *nl_proto_tab[256] = {
+	[NETLINK_ROUTE]          = "rtnl",
+	[NETLINK_UNUSED]         = "unused",
+	[NETLINK_USERSOCK]       = "usersock",
+	[NETLINK_FIREWALL]       = "fw",
+	[NETLINK_SOCK_DIAG]      = "tcpdiag",
+	[NETLINK_NFLOG]          = "nflog",
+	[NETLINK_XFRM]           = "xfrm",
+	[NETLINK_SELINUX]        = "selinux",
+	[NETLINK_ISCSI]          = "iscsi",
+	[NETLINK_AUDIT]          = "audit",
+	[NETLINK_FIB_LOOKUP]     = "fiblookup",
+	[NETLINK_CONNECTOR]      = "connector",
+	[NETLINK_NETFILTER]      = "nft",
+	[NETLINK_IP6_FW]         = "ip6fw",
+	[NETLINK_DNRTMSG]        = "dec-rt",
+	[NETLINK_KOBJECT_UEVENT] = "uevent",
+	[NETLINK_GENERIC]        = "genl",
+	[NETLINK_SCSITRANSPORT]  = "scsi-trans",
+	[NETLINK_ECRYPTFS]       = "ecryptfs",
+	[NETLINK_RDMA]           = "rdma",
+	[NETLINK_CRYPTO]         = "crypto",
+};
+
+static int nl_proto_init;
+
+static void nl_proto_initialize(void)
+{
+	nl_proto_init = 1;
+	rtnl_tab_initialize(CONFDIR "/nl_protos",
+			    nl_proto_tab, 256);
+}
+
+const char *nl_proto_n2a(int id, char *buf, int len)
+{
+	if (id < 0 || id >= 256 || numeric) {
+		snprintf(buf, len, "%d", id);
+		return buf;
+	}
+
+	if (!nl_proto_init)
+		nl_proto_initialize();
+
+	if (nl_proto_tab[id])
+		return nl_proto_tab[id];
+
+	snprintf(buf, len, "%u", id);
+	return buf;
+}
+
+int nl_proto_a2n(__u32 *id, const char *arg)
+{
+	static char *cache;
+	static unsigned long res;
+	char *end;
+	int i;
+
+	if (cache && strcmp(cache, arg) == 0) {
+		*id = res;
+		return 0;
+	}
+
+	if (!nl_proto_init)
+		nl_proto_initialize();
+
+	for (i = 0; i < 256; i++) {
+		if (nl_proto_tab[i] &&
+		    strcmp(nl_proto_tab[i], arg) == 0) {
+			cache = nl_proto_tab[i];
+			res = i;
+			*id = res;
+			return 0;
+		}
+	}
+
+	res = strtoul(arg, &end, 0);
+	if (!end || end == arg || *end || res > 255)
+		return -1;
+	*id = res;
+	return 0;
+}
+
+#define PROTODOWN_REASON_NUM_BITS 32
+static char *protodown_reason_tab[PROTODOWN_REASON_NUM_BITS] = {
+};
+
+static int protodown_reason_init;
+
+static void protodown_reason_initialize(void)
+{
+	struct dirent *de;
+	DIR *d;
+
+	protodown_reason_init = 1;
+
+	d = opendir(CONFDIR "/protodown_reasons.d");
+	if (!d)
+		return;
+
+	while ((de = readdir(d)) != NULL) {
+		char path[PATH_MAX];
+		size_t len;
+
+		if (*de->d_name == '.')
+			continue;
+
+		/* only consider filenames ending in '.conf' */
+		len = strlen(de->d_name);
+		if (len <= 5)
+			continue;
+		if (strcmp(de->d_name + len - 5, ".conf"))
+			continue;
+
+		snprintf(path, sizeof(path), CONFDIR "/protodown_reasons.d/%s",
+			 de->d_name);
+		rtnl_tab_initialize(path, protodown_reason_tab,
+				    PROTODOWN_REASON_NUM_BITS);
+	}
+	closedir(d);
+}
+
+int protodown_reason_n2a(int id, char *buf, int len)
+{
+	if (id < 0 || id >= PROTODOWN_REASON_NUM_BITS)
+		return -1;
+
+	if (numeric) {
+		snprintf(buf, len, "%d", id);
+		return 0;
+	}
+
+	if (!protodown_reason_init)
+		protodown_reason_initialize();
+
+	if (protodown_reason_tab[id])
+		snprintf(buf, len, "%s", protodown_reason_tab[id]);
+	else
+		snprintf(buf, len, "%d", id);
+
+	return 0;
+}
+
+int protodown_reason_a2n(__u32 *id, const char *arg)
+{
+	static char *cache;
+	static unsigned long res;
+	char *end;
+	int i;
+
+	if (cache && strcmp(cache, arg) == 0) {
+		*id = res;
+		return 0;
+	}
+
+	if (!protodown_reason_init)
+		protodown_reason_initialize();
+
+	for (i = 0; i < PROTODOWN_REASON_NUM_BITS; i++) {
+		if (protodown_reason_tab[i] &&
+		    strcmp(protodown_reason_tab[i], arg) == 0) {
+			cache = protodown_reason_tab[i];
+			res = i;
+			*id = res;
+			return 0;
+		}
+	}
+
+	res = strtoul(arg, &end, 0);
+	if (!end || end == arg || *end || res >= PROTODOWN_REASON_NUM_BITS)
+		return -1;
+	*id = res;
+	return 0;
+}
diff --git a/lib/utils.c b/lib/utils.c
new file mode 100644
index 0000000..dd3cdb3
--- /dev/null
+++ b/lib/utils.c
@@ -0,0 +1,1961 @@
+/*
+ * utils.c
+ *
+ *		This program is free software; you can redistribute it and/or
+ *		modify it under the terms of the GNU General Public License
+ *		as published by the Free Software Foundation; either version
+ *		2 of the License, or (at your option) any later version.
+ *
+ * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <string.h>
+#include <ctype.h>
+#include <netdb.h>
+#include <arpa/inet.h>
+#include <asm/types.h>
+#include <linux/pkt_sched.h>
+#include <linux/param.h>
+#include <linux/if_arp.h>
+#include <linux/mpls.h>
+#include <linux/snmp.h>
+#include <time.h>
+#include <sys/time.h>
+#include <errno.h>
+#ifdef HAVE_LIBCAP
+#include <sys/capability.h>
+#endif
+
+#include "rt_names.h"
+#include "utils.h"
+#include "ll_map.h"
+#include "namespace.h"
+
+int resolve_hosts;
+int timestamp_short;
+int pretty;
+const char *_SL_ = "\n";
+
+static int af_byte_len(int af);
+static void print_time(char *buf, int len, __u32 time);
+static void print_time64(char *buf, int len, __s64 time);
+
+int read_prop(const char *dev, char *prop, long *value)
+{
+	char fname[128], buf[80], *endp, *nl;
+	FILE *fp;
+	long result;
+	int ret;
+
+	ret = snprintf(fname, sizeof(fname), "/sys/class/net/%s/%s",
+			dev, prop);
+
+	if (ret <= 0 || ret >= sizeof(fname)) {
+		fprintf(stderr, "could not build pathname for property\n");
+		return -1;
+	}
+
+	fp = fopen(fname, "r");
+	if (fp == NULL) {
+		fprintf(stderr, "fopen %s: %s\n", fname, strerror(errno));
+		return -1;
+	}
+
+	if (!fgets(buf, sizeof(buf), fp)) {
+		fprintf(stderr, "property \"%s\" in file %s is currently unknown\n", prop, fname);
+		fclose(fp);
+		goto out;
+	}
+
+	nl = strchr(buf, '\n');
+	if (nl)
+		*nl = '\0';
+
+	fclose(fp);
+	result = strtol(buf, &endp, 0);
+
+	if (*endp || buf == endp) {
+		fprintf(stderr, "value \"%s\" in file %s is not a number\n",
+			buf, fname);
+		goto out;
+	}
+
+	if ((result == LONG_MAX || result == LONG_MIN) && errno == ERANGE) {
+		fprintf(stderr, "strtol %s: %s", fname, strerror(errno));
+		goto out;
+	}
+
+	*value = result;
+	return 0;
+out:
+	fprintf(stderr, "Failed to parse %s\n", fname);
+	return -1;
+}
+
+int get_hex(char c)
+{
+	if (c >= 'A' && c <= 'F')
+		return c - 'A' + 10;
+	if (c >= 'a' && c <= 'f')
+		return c - 'a' + 10;
+	if (c >= '0' && c <= '9')
+		return c - '0';
+
+	return -1;
+}
+
+int get_integer(int *val, const char *arg, int base)
+{
+	long res;
+	char *ptr;
+
+	if (!arg || !*arg)
+		return -1;
+
+	res = strtol(arg, &ptr, base);
+
+	/* If there were no digits at all, strtol()  stores
+	 * the original value of nptr in *endptr (and returns 0).
+	 * In particular, if *nptr is not '\0' but **endptr is '\0' on return,
+	 * the entire string is valid.
+	 */
+	if (!ptr || ptr == arg || *ptr)
+		return -1;
+
+	/* If an underflow occurs, strtol() returns LONG_MIN.
+	 * If an overflow occurs,  strtol() returns LONG_MAX.
+	 * In both cases, errno is set to ERANGE.
+	 */
+	if ((res == LONG_MAX || res == LONG_MIN) && errno == ERANGE)
+		return -1;
+
+	/* Outside range of int */
+	if (res < INT_MIN || res > INT_MAX)
+		return -1;
+
+	*val = res;
+	return 0;
+}
+
+int mask2bits(__u32 netmask)
+{
+	unsigned int bits = 0;
+	__u32 mask = ntohl(netmask);
+	__u32 host = ~mask;
+
+	/* a valid netmask must be 2^n - 1 */
+	if ((host & (host + 1)) != 0)
+		return -1;
+
+	for (; mask; mask <<= 1)
+		++bits;
+	return bits;
+}
+
+static int get_netmask(unsigned int *val, const char *arg, int base)
+{
+	inet_prefix addr;
+
+	if (!get_unsigned(val, arg, base))
+		return 0;
+
+	/* try converting dotted quad to CIDR */
+	if (!get_addr_1(&addr, arg, AF_INET) && addr.family == AF_INET) {
+		int b = mask2bits(addr.data[0]);
+
+		if (b >= 0) {
+			*val = b;
+			return 0;
+		}
+	}
+
+	return -1;
+}
+
+int get_unsigned(unsigned int *val, const char *arg, int base)
+{
+	unsigned long res;
+	char *ptr;
+
+	if (!arg || !*arg)
+		return -1;
+
+	res = strtoul(arg, &ptr, base);
+
+	/* empty string or trailing non-digits */
+	if (!ptr || ptr == arg || *ptr)
+		return -1;
+
+	/* overflow */
+	if (res == ULONG_MAX && errno == ERANGE)
+		return -1;
+
+	/* out side range of unsigned */
+	if (res > UINT_MAX)
+		return -1;
+
+	*val = res;
+	return 0;
+}
+
+/*
+ * get_time_rtt is "translated" from a similar routine "get_time" in
+ * tc_util.c.  We don't use the exact same routine because tc passes
+ * microseconds to the kernel and the callers of get_time_rtt want to
+ * pass milliseconds (standard unit for rtt values since 2.6.27), and
+ * have a different assumption for the units of a "raw" number.
+ */
+int get_time_rtt(unsigned int *val, const char *arg, int *raw)
+{
+	double t;
+	unsigned long res;
+	char *p;
+
+	if (strchr(arg, '.') != NULL) {
+		t = strtod(arg, &p);
+		if (t < 0.0)
+			return -1;
+
+		/* no digits? */
+		if (!p || p == arg)
+			return -1;
+
+		/* over/underflow */
+		if ((t == HUGE_VALF || t == HUGE_VALL) && errno == ERANGE)
+			return -1;
+	} else {
+		res = strtoul(arg, &p, 0);
+
+		/* empty string? */
+		if (!p || p == arg)
+			return -1;
+
+		/* overflow */
+		if (res == ULONG_MAX && errno == ERANGE)
+			return -1;
+
+		t = (double)res;
+	}
+
+	if (p == arg)
+		return -1;
+	*raw = 1;
+
+	if (*p) {
+		*raw = 0;
+		if (strcasecmp(p, "s") == 0 ||
+		    strcasecmp(p, "sec") == 0 ||
+		    strcasecmp(p, "secs") == 0)
+			t *= 1000;
+		else if (strcasecmp(p, "ms") == 0 ||
+			 strcasecmp(p, "msec") == 0 ||
+			 strcasecmp(p, "msecs") == 0)
+			t *= 1.0; /* allow suffix, do nothing */
+		else
+			return -1;
+	}
+
+	/* emulate ceil() without having to bring-in -lm and always be >= 1 */
+	*val = t;
+	if (*val < t)
+		*val += 1;
+
+	return 0;
+
+}
+
+int get_u64(__u64 *val, const char *arg, int base)
+{
+	unsigned long long res;
+	char *ptr;
+
+	if (!arg || !*arg)
+		return -1;
+
+	res = strtoull(arg, &ptr, base);
+
+	/* empty string or trailing non-digits */
+	if (!ptr || ptr == arg || *ptr)
+		return -1;
+
+	/* overflow */
+	if (res == ULLONG_MAX && errno == ERANGE)
+		return -1;
+
+	/* in case ULL is 128 bits */
+	if (res > 0xFFFFFFFFFFFFFFFFULL)
+		return -1;
+
+	*val = res;
+	return 0;
+}
+
+int get_u32(__u32 *val, const char *arg, int base)
+{
+	unsigned long res;
+	char *ptr;
+
+	if (!arg || !*arg)
+		return -1;
+	res = strtoul(arg, &ptr, base);
+
+	/* empty string or trailing non-digits */
+	if (!ptr || ptr == arg || *ptr)
+		return -1;
+
+	/* overflow */
+	if (res == ULONG_MAX && errno == ERANGE)
+		return -1;
+
+	/* in case UL > 32 bits */
+	if (res > 0xFFFFFFFFUL)
+		return -1;
+
+	*val = res;
+	return 0;
+}
+
+int get_u16(__u16 *val, const char *arg, int base)
+{
+	unsigned long res;
+	char *ptr;
+
+	if (!arg || !*arg)
+		return -1;
+	res = strtoul(arg, &ptr, base);
+
+	/* empty string or trailing non-digits */
+	if (!ptr || ptr == arg || *ptr)
+		return -1;
+
+	/* overflow */
+	if (res == ULONG_MAX && errno == ERANGE)
+		return -1;
+
+	if (res > 0xFFFFUL)
+		return -1;
+
+	*val = res;
+	return 0;
+}
+
+int get_u8(__u8 *val, const char *arg, int base)
+{
+	unsigned long res;
+	char *ptr;
+
+	if (!arg || !*arg)
+		return -1;
+
+	res = strtoul(arg, &ptr, base);
+	/* empty string or trailing non-digits */
+	if (!ptr || ptr == arg || *ptr)
+		return -1;
+
+	/* overflow */
+	if (res == ULONG_MAX && errno == ERANGE)
+		return -1;
+
+	if (res > 0xFFUL)
+		return -1;
+
+	*val = res;
+	return 0;
+}
+
+int get_s64(__s64 *val, const char *arg, int base)
+{
+	long long res;
+	char *ptr;
+
+	errno = 0;
+
+	if (!arg || !*arg)
+		return -1;
+	res = strtoll(arg, &ptr, base);
+	if (!ptr || ptr == arg || *ptr)
+		return -1;
+	if ((res == LLONG_MIN || res == LLONG_MAX) && errno == ERANGE)
+		return -1;
+	if (res > INT64_MAX || res < INT64_MIN)
+		return -1;
+
+	*val = res;
+	return 0;
+}
+
+int get_s32(__s32 *val, const char *arg, int base)
+{
+	long res;
+	char *ptr;
+
+	errno = 0;
+
+	if (!arg || !*arg)
+		return -1;
+	res = strtol(arg, &ptr, base);
+	if (!ptr || ptr == arg || *ptr)
+		return -1;
+	if ((res == LONG_MIN || res == LONG_MAX) && errno == ERANGE)
+		return -1;
+	if (res > INT32_MAX || res < INT32_MIN)
+		return -1;
+
+	*val = res;
+	return 0;
+}
+
+int get_be64(__be64 *val, const char *arg, int base)
+{
+	__u64 v;
+	int ret = get_u64(&v, arg, base);
+
+	if (!ret)
+		*val = htonll(v);
+
+	return ret;
+}
+
+int get_be32(__be32 *val, const char *arg, int base)
+{
+	__u32 v;
+	int ret = get_u32(&v, arg, base);
+
+	if (!ret)
+		*val = htonl(v);
+
+	return ret;
+}
+
+int get_be16(__be16 *val, const char *arg, int base)
+{
+	__u16 v;
+	int ret = get_u16(&v, arg, base);
+
+	if (!ret)
+		*val = htons(v);
+
+	return ret;
+}
+
+/* This uses a non-standard parsing (ie not inet_aton, or inet_pton)
+ * because of legacy choice to parse 10.8 as 10.8.0.0 not 10.0.0.8
+ */
+static int get_addr_ipv4(__u8 *ap, const char *cp)
+{
+	int i;
+
+	for (i = 0; i < 4; i++) {
+		unsigned long n;
+		char *endp;
+
+		n = strtoul(cp, &endp, 0);
+		if (n > 255)
+			return -1;	/* bogus network value */
+
+		if (endp == cp) /* no digits */
+			return -1;
+
+		ap[i] = n;
+
+		if (*endp == '\0')
+			break;
+
+		if (i == 3 || *endp != '.')
+			return -1;	/* extra characters */
+		cp = endp + 1;
+	}
+
+	return 1;
+}
+
+int get_addr64(__u64 *ap, const char *cp)
+{
+	int i;
+
+	union {
+		__u16 v16[4];
+		__u64 v64;
+	} val;
+
+	for (i = 0; i < 4; i++) {
+		unsigned long n;
+		char *endp;
+
+		n = strtoul(cp, &endp, 16);
+		if (n > 0xffff)
+			return -1;	/* bogus network value */
+
+		if (endp == cp) /* no digits */
+			return -1;
+
+		val.v16[i] = htons(n);
+
+		if (*endp == '\0')
+			break;
+
+		if (i == 3 || *endp != ':')
+			return -1;	/* extra characters */
+		cp = endp + 1;
+	}
+
+	*ap = val.v64;
+
+	return 1;
+}
+
+static void set_address_type(inet_prefix *addr)
+{
+	switch (addr->family) {
+	case AF_INET:
+		if (!addr->data[0])
+			addr->flags |= ADDRTYPE_INET_UNSPEC;
+		else if (IN_MULTICAST(ntohl(addr->data[0])))
+			addr->flags |= ADDRTYPE_INET_MULTI;
+		else
+			addr->flags |= ADDRTYPE_INET;
+		break;
+	case AF_INET6:
+		if (IN6_IS_ADDR_UNSPECIFIED(addr->data))
+			addr->flags |= ADDRTYPE_INET_UNSPEC;
+		else if (IN6_IS_ADDR_MULTICAST(addr->data))
+			addr->flags |= ADDRTYPE_INET_MULTI;
+		else
+			addr->flags |= ADDRTYPE_INET;
+		break;
+	}
+}
+
+static int __get_addr_1(inet_prefix *addr, const char *name, int family)
+{
+	memset(addr, 0, sizeof(*addr));
+
+	if (strcmp(name, "default") == 0) {
+		if (family == AF_MPLS)
+			return -1;
+		addr->family = family;
+		addr->bytelen = af_byte_len(addr->family);
+		addr->bitlen = -2;
+		addr->flags |= PREFIXLEN_SPECIFIED;
+		return 0;
+	}
+
+	if (strcmp(name, "all") == 0 ||
+	    strcmp(name, "any") == 0) {
+		if (family == AF_MPLS)
+			return -1;
+		addr->family = family;
+		addr->bytelen = 0;
+		addr->bitlen = -2;
+		return 0;
+	}
+
+	if (family == AF_PACKET) {
+		int len;
+
+		len = ll_addr_a2n((char *) &addr->data, sizeof(addr->data),
+				  name);
+		if (len < 0)
+			return -1;
+
+		addr->family = AF_PACKET;
+		addr->bytelen = len;
+		addr->bitlen = len * 8;
+		return 0;
+	}
+
+	if (strchr(name, ':')) {
+		addr->family = AF_INET6;
+		if (family != AF_UNSPEC && family != AF_INET6)
+			return -1;
+		if (inet_pton(AF_INET6, name, addr->data) <= 0)
+			return -1;
+		addr->bytelen = 16;
+		addr->bitlen = -1;
+		return 0;
+	}
+
+	if (family == AF_MPLS) {
+		unsigned int maxlabels;
+		int i;
+
+		addr->family = AF_MPLS;
+		if (mpls_pton(AF_MPLS, name, addr->data,
+			      sizeof(addr->data)) <= 0)
+			return -1;
+		addr->bytelen = 4;
+		addr->bitlen = 20;
+		/* How many bytes do I need? */
+		maxlabels = sizeof(addr->data) / sizeof(struct mpls_label);
+		for (i = 0; i < maxlabels; i++) {
+			if (ntohl(addr->data[i]) & MPLS_LS_S_MASK) {
+				addr->bytelen = (i + 1)*4;
+				break;
+			}
+		}
+		return 0;
+	}
+
+	addr->family = AF_INET;
+	if (family != AF_UNSPEC && family != AF_INET)
+		return -1;
+
+	if (get_addr_ipv4((__u8 *)addr->data, name) <= 0)
+		return -1;
+
+	addr->bytelen = 4;
+	addr->bitlen = -1;
+	return 0;
+}
+
+int get_addr_1(inet_prefix *addr, const char *name, int family)
+{
+	int ret;
+
+	ret = __get_addr_1(addr, name, family);
+	if (ret)
+		return ret;
+
+	set_address_type(addr);
+	return 0;
+}
+
+int af_bit_len(int af)
+{
+	switch (af) {
+	case AF_INET6:
+		return 128;
+	case AF_INET:
+		return 32;
+	case AF_MPLS:
+		return 20;
+	}
+
+	return 0;
+}
+
+static int af_byte_len(int af)
+{
+	return af_bit_len(af) / 8;
+}
+
+int get_prefix_1(inet_prefix *dst, char *arg, int family)
+{
+	char *slash;
+	int err, bitlen, flags;
+
+	slash = strchr(arg, '/');
+	if (slash)
+		*slash = 0;
+
+	err = get_addr_1(dst, arg, family);
+
+	if (slash)
+		*slash = '/';
+
+	if (err)
+		return err;
+
+	bitlen = af_bit_len(dst->family);
+
+	flags = 0;
+	if (slash) {
+		unsigned int plen;
+
+		if (dst->bitlen == -2)
+			return -1;
+		if (get_netmask(&plen, slash + 1, 0))
+			return -1;
+		if (plen > bitlen)
+			return -1;
+
+		flags |= PREFIXLEN_SPECIFIED;
+		bitlen = plen;
+	} else {
+		if (dst->bitlen == -2)
+			bitlen = 0;
+	}
+
+	dst->flags |= flags;
+	dst->bitlen = bitlen;
+
+	return 0;
+}
+
+static const char *family_name_verbose(int family)
+{
+	if (family == AF_UNSPEC)
+		return "any valid";
+	return family_name(family);
+}
+
+int get_addr(inet_prefix *dst, const char *arg, int family)
+{
+	if (get_addr_1(dst, arg, family)) {
+		fprintf(stderr,
+			"Error: %s address is expected rather than \"%s\".\n",
+			family_name_verbose(family), arg);
+		exit(1);
+	}
+	return 0;
+}
+
+int get_addr_rta(inet_prefix *dst, const struct rtattr *rta, int family)
+{
+	const int len = RTA_PAYLOAD(rta);
+	const void *data = RTA_DATA(rta);
+
+	switch (len) {
+	case 4:
+		dst->family = AF_INET;
+		dst->bytelen = 4;
+		memcpy(dst->data, data, 4);
+		break;
+	case 16:
+		dst->family = AF_INET6;
+		dst->bytelen = 16;
+		memcpy(dst->data, data, 16);
+		break;
+	default:
+		return -1;
+	}
+
+	if (family != AF_UNSPEC && family != dst->family)
+		return -2;
+
+	dst->bitlen = -1;
+	dst->flags = 0;
+
+	set_address_type(dst);
+	return 0;
+}
+
+int get_prefix(inet_prefix *dst, char *arg, int family)
+{
+	if (family == AF_PACKET) {
+		fprintf(stderr,
+			"Error: \"%s\" may be inet prefix, but it is not allowed in this context.\n",
+			arg);
+		exit(1);
+	}
+
+	if (get_prefix_1(dst, arg, family)) {
+		fprintf(stderr,
+			"Error: %s prefix is expected rather than \"%s\".\n",
+			family_name_verbose(family), arg);
+		exit(1);
+	}
+	return 0;
+}
+
+__u32 get_addr32(const char *name)
+{
+	inet_prefix addr;
+
+	if (get_addr_1(&addr, name, AF_INET)) {
+		fprintf(stderr,
+			"Error: an IP address is expected rather than \"%s\"\n",
+			name);
+		exit(1);
+	}
+	return addr.data[0];
+}
+
+void incomplete_command(void)
+{
+	fprintf(stderr, "Command line is not complete. Try option \"help\"\n");
+	exit(-1);
+}
+
+void missarg(const char *key)
+{
+	fprintf(stderr, "Error: argument \"%s\" is required\n", key);
+	exit(-1);
+}
+
+void invarg(const char *msg, const char *arg)
+{
+	fprintf(stderr, "Error: argument \"%s\" is wrong: %s\n", arg, msg);
+	exit(-1);
+}
+
+void duparg(const char *key, const char *arg)
+{
+	fprintf(stderr,
+		"Error: duplicate \"%s\": \"%s\" is the second value.\n",
+		key, arg);
+	exit(-1);
+}
+
+void duparg2(const char *key, const char *arg)
+{
+	fprintf(stderr,
+		"Error: either \"%s\" is duplicate, or \"%s\" is a garbage.\n",
+		key, arg);
+	exit(-1);
+}
+
+int nodev(const char *dev)
+{
+	fprintf(stderr, "Cannot find device \"%s\"\n", dev);
+	return -1;
+}
+
+static int __check_ifname(const char *name)
+{
+	if (*name == '\0')
+		return -1;
+	while (*name) {
+		if (*name == '/' || isspace(*name))
+			return -1;
+		++name;
+	}
+	return 0;
+}
+
+int check_ifname(const char *name)
+{
+	/* These checks mimic kernel checks in dev_valid_name */
+	if (strlen(name) >= IFNAMSIZ)
+		return -1;
+	return __check_ifname(name);
+}
+
+int check_altifname(const char *name)
+{
+	return __check_ifname(name);
+}
+
+/* buf is assumed to be IFNAMSIZ */
+int get_ifname(char *buf, const char *name)
+{
+	int ret;
+
+	ret = check_ifname(name);
+	if (ret == 0)
+		strncpy(buf, name, IFNAMSIZ);
+
+	return ret;
+}
+
+const char *get_ifname_rta(int ifindex, const struct rtattr *rta)
+{
+	const char *name;
+
+	if (rta) {
+		name = rta_getattr_str(rta);
+	} else {
+		fprintf(stderr,
+			"BUG: device with ifindex %d has nil ifname\n",
+			ifindex);
+		name = ll_idx_n2a(ifindex);
+	}
+
+	if (check_ifname(name))
+		return NULL;
+
+	return name;
+}
+
+/* Returns false if 'prefix' is a not empty prefix of 'string'.
+ */
+bool matches(const char *prefix, const char *string)
+{
+	if (!*prefix)
+		return true;
+	while (*string && *prefix == *string) {
+		prefix++;
+		string++;
+	}
+
+	return !!*prefix;
+}
+
+int inet_addr_match(const inet_prefix *a, const inet_prefix *b, int bits)
+{
+	const __u32 *a1 = a->data;
+	const __u32 *a2 = b->data;
+	int words = bits >> 0x05;
+
+	bits &= 0x1f;
+
+	if (words)
+		if (memcmp(a1, a2, words << 2))
+			return -1;
+
+	if (bits) {
+		__u32 w1, w2;
+		__u32 mask;
+
+		w1 = a1[words];
+		w2 = a2[words];
+
+		mask = htonl((0xffffffff) << (0x20 - bits));
+
+		if ((w1 ^ w2) & mask)
+			return 1;
+	}
+
+	return 0;
+}
+
+int inet_addr_match_rta(const inet_prefix *m, const struct rtattr *rta)
+{
+	inet_prefix dst;
+
+	if (!rta || m->family == AF_UNSPEC || m->bitlen <= 0)
+		return 0;
+
+	if (get_addr_rta(&dst, rta, m->family))
+		return -1;
+
+	return inet_addr_match(&dst, m, m->bitlen);
+}
+
+int __iproute2_hz_internal;
+
+int __get_hz(void)
+{
+	char name[1024];
+	int hz = 0;
+	FILE *fp;
+
+	if (getenv("HZ"))
+		return atoi(getenv("HZ")) ? : HZ;
+
+	if (getenv("PROC_NET_PSCHED"))
+		snprintf(name, sizeof(name)-1,
+			 "%s", getenv("PROC_NET_PSCHED"));
+	else if (getenv("PROC_ROOT"))
+		snprintf(name, sizeof(name)-1,
+			 "%s/net/psched", getenv("PROC_ROOT"));
+	else
+		strcpy(name, "/proc/net/psched");
+
+	fp = fopen(name, "r");
+
+	if (fp) {
+		unsigned int nom, denom;
+
+		if (fscanf(fp, "%*08x%*08x%08x%08x", &nom, &denom) == 2)
+			if (nom == 1000000)
+				hz = denom;
+		fclose(fp);
+	}
+	if (hz)
+		return hz;
+	return HZ;
+}
+
+int __iproute2_user_hz_internal;
+
+int __get_user_hz(void)
+{
+	return sysconf(_SC_CLK_TCK);
+}
+
+const char *rt_addr_n2a_r(int af, int len,
+			  const void *addr, char *buf, int buflen)
+{
+	switch (af) {
+	case AF_INET:
+	case AF_INET6:
+		return inet_ntop(af, addr, buf, buflen);
+	case AF_MPLS:
+		return mpls_ntop(af, addr, buf, buflen);
+	case AF_PACKET:
+		return ll_addr_n2a(addr, len, ARPHRD_VOID, buf, buflen);
+	case AF_BRIDGE:
+	{
+		const union {
+			struct sockaddr sa;
+			struct sockaddr_in sin;
+			struct sockaddr_in6 sin6;
+		} *sa = addr;
+
+		switch (sa->sa.sa_family) {
+		case AF_INET:
+			return inet_ntop(AF_INET, &sa->sin.sin_addr,
+					 buf, buflen);
+		case AF_INET6:
+			return inet_ntop(AF_INET6, &sa->sin6.sin6_addr,
+					 buf, buflen);
+		}
+
+		/* fallthrough */
+	}
+	default:
+		return "???";
+	}
+}
+
+const char *rt_addr_n2a(int af, int len, const void *addr)
+{
+	static char buf[256];
+
+	return rt_addr_n2a_r(af, len, addr, buf, 256);
+}
+
+int read_family(const char *name)
+{
+	int family = AF_UNSPEC;
+
+	if (strcmp(name, "inet") == 0)
+		family = AF_INET;
+	else if (strcmp(name, "inet6") == 0)
+		family = AF_INET6;
+	else if (strcmp(name, "link") == 0)
+		family = AF_PACKET;
+	else if (strcmp(name, "mpls") == 0)
+		family = AF_MPLS;
+	else if (strcmp(name, "bridge") == 0)
+		family = AF_BRIDGE;
+	return family;
+}
+
+const char *family_name(int family)
+{
+	if (family == AF_INET)
+		return "inet";
+	if (family == AF_INET6)
+		return "inet6";
+	if (family == AF_PACKET)
+		return "link";
+	if (family == AF_MPLS)
+		return "mpls";
+	if (family == AF_BRIDGE)
+		return "bridge";
+	return "???";
+}
+
+#ifdef RESOLVE_HOSTNAMES
+struct namerec {
+	struct namerec *next;
+	const char *name;
+	inet_prefix addr;
+};
+
+#define NHASH 257
+static struct namerec *nht[NHASH];
+
+static const char *resolve_address(const void *addr, int len, int af)
+{
+	struct namerec *n;
+	struct hostent *h_ent;
+	unsigned int hash;
+	static int notfirst;
+
+
+	if (af == AF_INET6 && ((__u32 *)addr)[0] == 0 &&
+	    ((__u32 *)addr)[1] == 0 && ((__u32 *)addr)[2] == htonl(0xffff)) {
+		af = AF_INET;
+		addr += 12;
+		len = 4;
+	}
+
+	hash = *(__u32 *)(addr + len - 4) % NHASH;
+
+	for (n = nht[hash]; n; n = n->next) {
+		if (n->addr.family == af &&
+		    n->addr.bytelen == len &&
+		    memcmp(n->addr.data, addr, len) == 0)
+			return n->name;
+	}
+	n = malloc(sizeof(*n));
+	if (n == NULL)
+		return NULL;
+	n->addr.family = af;
+	n->addr.bytelen = len;
+	n->name = NULL;
+	memcpy(n->addr.data, addr, len);
+	n->next = nht[hash];
+	nht[hash] = n;
+	if (++notfirst == 1)
+		sethostent(1);
+	fflush(stdout);
+
+	h_ent = gethostbyaddr(addr, len, af);
+	if (h_ent != NULL)
+		n->name = strdup(h_ent->h_name);
+
+	/* Even if we fail, "negative" entry is remembered. */
+	return n->name;
+}
+#endif
+
+const char *format_host_r(int af, int len, const void *addr,
+			char *buf, int buflen)
+{
+#ifdef RESOLVE_HOSTNAMES
+	if (resolve_hosts) {
+		const char *n;
+
+		len = len <= 0 ? af_byte_len(af) : len;
+
+		if (len > 0 &&
+		    (n = resolve_address(addr, len, af)) != NULL)
+			return n;
+	}
+#endif
+	return rt_addr_n2a_r(af, len, addr, buf, buflen);
+}
+
+const char *format_host(int af, int len, const void *addr)
+{
+	static char buf[256];
+
+	return format_host_r(af, len, addr, buf, 256);
+}
+
+
+char *hexstring_n2a(const __u8 *str, int len, char *buf, int blen)
+{
+	char *ptr = buf;
+	int i;
+
+	for (i = 0; i < len; i++) {
+		if (blen < 3)
+			break;
+		sprintf(ptr, "%02x", str[i]);
+		ptr += 2;
+		blen -= 2;
+	}
+	return buf;
+}
+
+__u8 *hexstring_a2n(const char *str, __u8 *buf, int blen, unsigned int *len)
+{
+	unsigned int cnt = 0;
+	char *endptr;
+
+	if (strlen(str) % 2)
+		return NULL;
+	while (cnt < blen && strlen(str) > 1) {
+		unsigned int tmp;
+		char tmpstr[3];
+
+		strncpy(tmpstr, str, 2);
+		tmpstr[2] = '\0';
+		errno = 0;
+		tmp = strtoul(tmpstr, &endptr, 16);
+		if (errno != 0 || tmp > 0xFF || *endptr != '\0')
+			return NULL;
+		buf[cnt++] = tmp;
+		str += 2;
+	}
+
+	if (len)
+		*len = cnt;
+
+	return buf;
+}
+
+int hex2mem(const char *buf, uint8_t *mem, int count)
+{
+	int i, j;
+	int c;
+
+	for (i = 0, j = 0; i < count; i++, j += 2) {
+		c = get_hex(buf[j]);
+		if (c < 0)
+			return -1;
+
+		mem[i] = c << 4;
+
+		c = get_hex(buf[j + 1]);
+		if (c < 0)
+			return -1;
+
+		mem[i] |= c;
+	}
+
+	return 0;
+}
+
+int addr64_n2a(__u64 addr, char *buff, size_t len)
+{
+	__u16 *words = (__u16 *)&addr;
+	__u16 v;
+	int i, ret;
+	size_t written = 0;
+	char *sep = ":";
+
+	for (i = 0; i < 4; i++) {
+		v = ntohs(words[i]);
+
+		if (i == 3)
+			sep = "";
+
+		ret = snprintf(&buff[written], len - written, "%x%s", v, sep);
+		if (ret < 0)
+			return ret;
+
+		written += ret;
+	}
+
+	return written;
+}
+
+/* Print buffer and escape bytes that are !isprint or among 'escape' */
+void print_escape_buf(const __u8 *buf, size_t len, const char *escape)
+{
+	size_t i;
+
+	for (i = 0; i < len; ++i) {
+		if (isprint(buf[i]) && buf[i] != '\\' &&
+		    !strchr(escape, buf[i]))
+			printf("%c", buf[i]);
+		else
+			printf("\\%03o", buf[i]);
+	}
+}
+
+int print_timestamp(FILE *fp)
+{
+	struct timeval tv;
+	struct tm *tm;
+
+	gettimeofday(&tv, NULL);
+	tm = localtime(&tv.tv_sec);
+
+	if (timestamp_short) {
+		char tshort[40];
+
+		strftime(tshort, sizeof(tshort), "%Y-%m-%dT%H:%M:%S", tm);
+		fprintf(fp, "[%s.%06ld] ", tshort, tv.tv_usec);
+	} else {
+		char *tstr = asctime(tm);
+
+		tstr[strlen(tstr)-1] = 0;
+		fprintf(fp, "Timestamp: %s %ld usec\n",
+			tstr, tv.tv_usec);
+	}
+
+	return 0;
+}
+
+unsigned int print_name_and_link(const char *fmt,
+				 const char *name, struct rtattr *tb[])
+{
+	const char *link = NULL;
+	unsigned int m_flag = 0;
+	SPRINT_BUF(b1);
+
+	if (tb[IFLA_LINK]) {
+		int iflink = rta_getattr_u32(tb[IFLA_LINK]);
+
+		if (iflink) {
+			if (tb[IFLA_LINK_NETNSID]) {
+				if (is_json_context()) {
+					print_int(PRINT_JSON,
+						  "link_index", NULL, iflink);
+				} else {
+					link = ll_idx_n2a(iflink);
+				}
+			} else {
+				link = ll_index_to_name(iflink);
+
+				if (is_json_context()) {
+					print_string(PRINT_JSON,
+						     "link", NULL, link);
+					link = NULL;
+				}
+
+				m_flag = ll_index_to_flags(iflink);
+				m_flag = !(m_flag & IFF_UP);
+			}
+		} else {
+			if (is_json_context())
+				print_null(PRINT_JSON, "link", NULL, NULL);
+			else
+				link = "NONE";
+		}
+
+		if (link) {
+			snprintf(b1, sizeof(b1), "%s@%s", name, link);
+			name = b1;
+		}
+	}
+
+	print_color_string(PRINT_ANY, COLOR_IFNAME, "ifname", fmt, name);
+
+	return m_flag;
+}
+
+int cmdlineno;
+
+/* Like glibc getline but handle continuation lines and comments */
+ssize_t getcmdline(char **linep, size_t *lenp, FILE *in)
+{
+	ssize_t cc;
+	char *cp;
+
+	cc = getline(linep, lenp, in);
+	if (cc < 0)
+		return cc;	/* eof or error */
+	++cmdlineno;
+
+	cp = strchr(*linep, '#');
+	if (cp)
+		*cp = '\0';
+
+	while ((cp = strstr(*linep, "\\\n")) != NULL) {
+		char *line1 = NULL;
+		size_t len1 = 0;
+		ssize_t cc1;
+
+		cc1 = getline(&line1, &len1, in);
+		if (cc1 < 0) {
+			fprintf(stderr, "Missing continuation line\n");
+			return cc1;
+		}
+
+		++cmdlineno;
+		*cp = 0;
+
+		cp = strchr(line1, '#');
+		if (cp)
+			*cp = '\0';
+
+		*lenp = strlen(*linep) + strlen(line1) + 1;
+		*linep = realloc(*linep, *lenp);
+		if (!*linep) {
+			fprintf(stderr, "Out of memory\n");
+			*lenp = 0;
+			return -1;
+		}
+		cc += cc1 - 2;
+		strcat(*linep, line1);
+		free(line1);
+	}
+	return cc;
+}
+
+/* split command line into argument vector */
+int makeargs(char *line, char *argv[], int maxargs)
+{
+	static const char ws[] = " \t\r\n";
+	char *cp = line;
+	int argc = 0;
+
+	while (*cp) {
+		/* skip leading whitespace */
+		cp += strspn(cp, ws);
+
+		if (*cp == '\0')
+			break;
+
+		if (argc >= (maxargs - 1)) {
+			fprintf(stderr, "Too many arguments to command\n");
+			exit(1);
+		}
+
+		/* word begins with quote */
+		if (*cp == '\'' || *cp == '"') {
+			char quote = *cp++;
+
+			argv[argc++] = cp;
+			/* find ending quote */
+			cp = strchr(cp, quote);
+			if (cp == NULL) {
+				fprintf(stderr, "Unterminated quoted string\n");
+				exit(1);
+			}
+		} else {
+			argv[argc++] = cp;
+
+			/* find end of word */
+			cp += strcspn(cp, ws);
+			if (*cp == '\0')
+				break;
+		}
+
+		/* separate words */
+		*cp++ = 0;
+	}
+	argv[argc] = NULL;
+
+	return argc;
+}
+
+void print_nlmsg_timestamp(FILE *fp, const struct nlmsghdr *n)
+{
+	char *tstr;
+	time_t secs = ((__u32 *)NLMSG_DATA(n))[0];
+	long usecs = ((__u32 *)NLMSG_DATA(n))[1];
+
+	tstr = asctime(localtime(&secs));
+	tstr[strlen(tstr)-1] = 0;
+	fprintf(fp, "Timestamp: %s %lu us\n", tstr, usecs);
+}
+
+char *int_to_str(int val, char *buf)
+{
+	sprintf(buf, "%d", val);
+	return buf;
+}
+
+int get_guid(__u64 *guid, const char *arg)
+{
+	unsigned long tmp;
+	char *endptr;
+	int i;
+
+#define GUID_STR_LEN 23
+	/* Verify strict format: format string must be
+	 * xx:xx:xx:xx:xx:xx:xx:xx where xx can be an arbitrary
+	 * hex digit
+	 */
+
+	if (strlen(arg) != GUID_STR_LEN)
+		return -1;
+
+	/* make sure columns are in place */
+	for (i = 0; i < 7; i++)
+		if (arg[2 + i * 3] != ':')
+			return -1;
+
+	*guid = 0;
+	for (i = 0; i < 8; i++) {
+		tmp = strtoul(arg + i * 3, &endptr, 16);
+		if (endptr != arg + i * 3 + 2)
+			return -1;
+
+		if (tmp > 255)
+			return -1;
+
+		*guid |= tmp << (56 - 8 * i);
+	}
+
+	return 0;
+}
+
+/* This is a necessary workaround for multicast route dumps */
+int get_real_family(int rtm_type, int rtm_family)
+{
+	if (rtm_type != RTN_MULTICAST)
+		return rtm_family;
+
+	if (rtm_family == RTNL_FAMILY_IPMR)
+		return AF_INET;
+
+	if (rtm_family == RTNL_FAMILY_IP6MR)
+		return AF_INET6;
+
+	return rtm_family;
+}
+
+/* Based on copy_rtnl_link_stats() from kernel at net/core/rtnetlink.c */
+static void copy_rtnl_link_stats64(struct rtnl_link_stats64 *stats64,
+				   const struct rtnl_link_stats *stats)
+{
+	__u64 *a = (__u64 *)stats64;
+	const __u32 *b = (const __u32 *)stats;
+	const __u32 *e = b + sizeof(*stats) / sizeof(*b);
+
+	while (b < e)
+		*a++ = *b++;
+}
+
+#define IPSTATS_MIB_MAX_LEN	(__IPSTATS_MIB_MAX * sizeof(__u64))
+static void get_snmp_counters(struct rtnl_link_stats64 *stats64,
+			      struct rtattr *s)
+{
+	__u64 *mib = (__u64 *)RTA_DATA(s);
+
+	memset(stats64, 0, sizeof(*stats64));
+
+	stats64->rx_packets = mib[IPSTATS_MIB_INPKTS];
+	stats64->rx_bytes = mib[IPSTATS_MIB_INOCTETS];
+	stats64->tx_packets = mib[IPSTATS_MIB_OUTPKTS];
+	stats64->tx_bytes = mib[IPSTATS_MIB_OUTOCTETS];
+	stats64->rx_errors = mib[IPSTATS_MIB_INDISCARDS];
+	stats64->tx_errors = mib[IPSTATS_MIB_OUTDISCARDS];
+	stats64->multicast = mib[IPSTATS_MIB_INMCASTPKTS];
+	stats64->rx_frame_errors = mib[IPSTATS_MIB_CSUMERRORS];
+}
+
+int get_rtnl_link_stats_rta(struct rtnl_link_stats64 *stats64,
+			    struct rtattr *tb[])
+{
+	struct rtnl_link_stats stats;
+	void *s;
+	struct rtattr *rta;
+	int size, len;
+
+	if (tb[IFLA_STATS64]) {
+		rta = tb[IFLA_STATS64];
+		size = sizeof(struct rtnl_link_stats64);
+		s = stats64;
+	} else if (tb[IFLA_STATS]) {
+		rta = tb[IFLA_STATS];
+		size = sizeof(struct rtnl_link_stats);
+		s = &stats;
+	} else if (tb[IFLA_PROTINFO]) {
+		struct rtattr *ptb[IPSTATS_MIB_MAX_LEN + 1];
+
+		parse_rtattr_nested(ptb, IPSTATS_MIB_MAX_LEN,
+				    tb[IFLA_PROTINFO]);
+		if (ptb[IFLA_INET6_STATS])
+			get_snmp_counters(stats64, ptb[IFLA_INET6_STATS]);
+		return sizeof(*stats64);
+	} else {
+		return -1;
+	}
+
+	len = RTA_PAYLOAD(rta);
+	if (len < size)
+		memset(s + len, 0, size - len);
+	else
+		len = size;
+
+	memcpy(s, RTA_DATA(rta), len);
+
+	if (s != stats64)
+		copy_rtnl_link_stats64(stats64, s);
+	return size;
+}
+
+#ifdef NEED_STRLCPY
+size_t strlcpy(char *dst, const char *src, size_t size)
+{
+	size_t srclen = strlen(src);
+
+	if (size) {
+		size_t minlen = min(srclen, size - 1);
+
+		memcpy(dst, src, minlen);
+		dst[minlen] = '\0';
+	}
+	return srclen;
+}
+
+size_t strlcat(char *dst, const char *src, size_t size)
+{
+	size_t dlen = strlen(dst);
+
+	if (dlen >= size)
+		return dlen + strlen(src);
+
+	return dlen + strlcpy(dst + dlen, src, size - dlen);
+}
+#endif
+
+void drop_cap(void)
+{
+#ifdef HAVE_LIBCAP
+	/* don't harmstring root/sudo */
+	if (getuid() != 0 && geteuid() != 0) {
+		cap_t capabilities;
+		cap_value_t net_admin = CAP_NET_ADMIN;
+		cap_flag_t inheritable = CAP_INHERITABLE;
+		cap_flag_value_t is_set;
+
+		capabilities = cap_get_proc();
+		if (!capabilities)
+			exit(EXIT_FAILURE);
+		if (cap_get_flag(capabilities, net_admin, inheritable,
+		    &is_set) != 0)
+			exit(EXIT_FAILURE);
+		/* apps with ambient caps can fork and call ip */
+		if (is_set == CAP_CLEAR) {
+			if (cap_clear(capabilities) != 0)
+				exit(EXIT_FAILURE);
+			if (cap_set_proc(capabilities) != 0)
+				exit(EXIT_FAILURE);
+		}
+		cap_free(capabilities);
+	}
+#endif
+}
+
+int get_time(unsigned int *time, const char *str)
+{
+	double t;
+	char *p;
+
+	t = strtod(str, &p);
+	if (p == str)
+		return -1;
+
+	if (*p) {
+		if (strcasecmp(p, "s") == 0 || strcasecmp(p, "sec") == 0 ||
+		    strcasecmp(p, "secs") == 0)
+			t *= TIME_UNITS_PER_SEC;
+		else if (strcasecmp(p, "ms") == 0 || strcasecmp(p, "msec") == 0 ||
+			 strcasecmp(p, "msecs") == 0)
+			t *= TIME_UNITS_PER_SEC/1000;
+		else if (strcasecmp(p, "us") == 0 || strcasecmp(p, "usec") == 0 ||
+			 strcasecmp(p, "usecs") == 0)
+			t *= TIME_UNITS_PER_SEC/1000000;
+		else
+			return -1;
+	}
+
+	*time = t;
+	return 0;
+}
+
+static void print_time(char *buf, int len, __u32 time)
+{
+	double tmp = time;
+
+	if (tmp >= TIME_UNITS_PER_SEC)
+		snprintf(buf, len, "%.3gs", tmp/TIME_UNITS_PER_SEC);
+	else if (tmp >= TIME_UNITS_PER_SEC/1000)
+		snprintf(buf, len, "%.3gms", tmp/(TIME_UNITS_PER_SEC/1000));
+	else
+		snprintf(buf, len, "%uus", time);
+}
+
+char *sprint_time(__u32 time, char *buf)
+{
+	print_time(buf, SPRINT_BSIZE-1, time);
+	return buf;
+}
+
+/* 64 bit times are represented internally in nanoseconds */
+int get_time64(__s64 *time, const char *str)
+{
+	double nsec;
+	char *p;
+
+	nsec = strtod(str, &p);
+	if (p == str)
+		return -1;
+
+	if (*p) {
+		if (strcasecmp(p, "s") == 0 ||
+		    strcasecmp(p, "sec") == 0 ||
+		    strcasecmp(p, "secs") == 0)
+			nsec *= NSEC_PER_SEC;
+		else if (strcasecmp(p, "ms") == 0 ||
+			 strcasecmp(p, "msec") == 0 ||
+			 strcasecmp(p, "msecs") == 0)
+			nsec *= NSEC_PER_MSEC;
+		else if (strcasecmp(p, "us") == 0 ||
+			 strcasecmp(p, "usec") == 0 ||
+			 strcasecmp(p, "usecs") == 0)
+			nsec *= NSEC_PER_USEC;
+		else if (strcasecmp(p, "ns") == 0 ||
+			 strcasecmp(p, "nsec") == 0 ||
+			 strcasecmp(p, "nsecs") == 0)
+			nsec *= 1;
+		else
+			return -1;
+	}
+
+	*time = nsec;
+	return 0;
+}
+
+static void print_time64(char *buf, int len, __s64 time)
+{
+	double nsec = time;
+
+	if (time >= NSEC_PER_SEC)
+		snprintf(buf, len, "%.3gs", nsec/NSEC_PER_SEC);
+	else if (time >= NSEC_PER_MSEC)
+		snprintf(buf, len, "%.3gms", nsec/NSEC_PER_MSEC);
+	else if (time >= NSEC_PER_USEC)
+		snprintf(buf, len, "%.3gus", nsec/NSEC_PER_USEC);
+	else
+		snprintf(buf, len, "%lldns", time);
+}
+
+char *sprint_time64(__s64 time, char *buf)
+{
+	print_time64(buf, SPRINT_BSIZE-1, time);
+	return buf;
+}
+
+int do_batch(const char *name, bool force,
+	     int (*cmd)(int argc, char *argv[], void *data), void *data)
+{
+	char *line = NULL;
+	size_t len = 0;
+	int ret = EXIT_SUCCESS;
+
+	if (name && strcmp(name, "-") != 0) {
+		if (freopen(name, "r", stdin) == NULL) {
+			fprintf(stderr,
+				"Cannot open file \"%s\" for reading: %s\n",
+				name, strerror(errno));
+			return EXIT_FAILURE;
+		}
+	}
+
+	cmdlineno = 0;
+	while (getcmdline(&line, &len, stdin) != -1) {
+		char *largv[MAX_ARGS];
+		int largc;
+
+		largc = makeargs(line, largv, MAX_ARGS);
+		if (!largc)
+			continue;	/* blank line */
+
+		if (cmd(largc, largv, data)) {
+			fprintf(stderr, "Command failed %s:%d\n",
+				name, cmdlineno);
+			ret = EXIT_FAILURE;
+			if (!force)
+				break;
+		}
+	}
+
+	if (line)
+		free(line);
+
+	return ret;
+}
+
+int parse_one_of(const char *msg, const char *realval, const char * const *list,
+		 size_t len, int *p_err)
+{
+	int i;
+
+	for (i = 0; i < len; i++) {
+		if (list[i] && matches(realval, list[i]) == 0) {
+			*p_err = 0;
+			return i;
+		}
+	}
+
+	fprintf(stderr, "Error: argument of \"%s\" must be one of ", msg);
+	for (i = 0; i < len; i++)
+		if (list[i])
+			fprintf(stderr, "\"%s\", ", list[i]);
+	fprintf(stderr, "not \"%s\"\n", realval);
+	*p_err = -EINVAL;
+	return 0;
+}
+
+bool parse_on_off(const char *msg, const char *realval, int *p_err)
+{
+	static const char * const values_on_off[] = { "off", "on" };
+
+	return parse_one_of(msg, realval, values_on_off, ARRAY_SIZE(values_on_off), p_err);
+}
+
+int parse_mapping_gen(int *argcp, char ***argvp,
+		      int (*key_cb)(__u32 *keyp, const char *key),
+		      int (*mapping_cb)(__u32 key, char *value, void *data),
+		      void *mapping_cb_data)
+{
+	int argc = *argcp;
+	char **argv = *argvp;
+	int ret = 0;
+
+	while (argc > 0) {
+		char *colon = strchr(*argv, ':');
+		__u32 key;
+
+		if (!colon)
+			break;
+		*colon = '\0';
+
+		if (key_cb(&key, *argv)) {
+			ret = 1;
+			break;
+		}
+		if (mapping_cb(key, colon + 1, mapping_cb_data)) {
+			ret = 1;
+			break;
+		}
+
+		argc--, argv++;
+	}
+
+	*argcp = argc;
+	*argvp = argv;
+	return ret;
+}
+
+static int parse_mapping_num(__u32 *keyp, const char *key)
+{
+	return get_u32(keyp, key, 0);
+}
+
+int parse_mapping_num_all(__u32 *keyp, const char *key)
+{
+	if (matches(key, "all") == 0) {
+		*keyp = (__u32) -1;
+		return 0;
+	}
+	return parse_mapping_num(keyp, key);
+}
+
+int parse_mapping(int *argcp, char ***argvp, bool allow_all,
+		  int (*mapping_cb)(__u32 key, char *value, void *data),
+		  void *mapping_cb_data)
+{
+	if (allow_all)
+		return parse_mapping_gen(argcp, argvp, parse_mapping_num_all,
+					 mapping_cb, mapping_cb_data);
+	else
+		return parse_mapping_gen(argcp, argvp, parse_mapping_num,
+					 mapping_cb, mapping_cb_data);
+}
+
+int str_map_lookup_str(const struct str_num_map *map, const char *needle)
+{
+	if (!needle)
+		return -EINVAL;
+
+	/* Process array which is NULL terminated by the string. */
+	while (map && map->str) {
+		if (strcmp(map->str, needle) == 0)
+			return map->num;
+
+		map++;
+	}
+	return -EINVAL;
+}
+
+const char *str_map_lookup_uint(const struct str_num_map *map, unsigned int val)
+{
+	unsigned int num = val;
+
+	while (map && map->str) {
+		if (num == map->num)
+			return map->str;
+
+		map++;
+	}
+	return NULL;
+}
+
+const char *str_map_lookup_u16(const struct str_num_map *map, uint16_t val)
+{
+	unsigned int num = val;
+
+	while (map && map->str) {
+		if (num == map->num)
+			return map->str;
+
+		map++;
+	}
+	return NULL;
+}
+
+const char *str_map_lookup_u8(const struct str_num_map *map, uint8_t val)
+{
+	unsigned int num = val;
+
+	while (map && map->str) {
+		if (num == map->num)
+			return map->str;
+
+		map++;
+	}
+	return NULL;
+}
+
+unsigned int get_str_char_count(const char *str, int match)
+{
+	unsigned int count = 0;
+	const char *pos = str;
+
+	while ((pos = strchr(pos, match))) {
+		count++;
+		pos++;
+	}
+	return count;
+}
+
+int str_split_by_char(char *str, char **before, char **after, int match)
+{
+	char *slash;
+
+	slash = strrchr(str, match);
+	if (!slash)
+		return -EINVAL;
+	*slash = '\0';
+	*before = str;
+	*after = slash + 1;
+	return 0;
+}
+
+struct indent_mem *alloc_indent_mem(void)
+{
+	struct indent_mem *mem = malloc(sizeof(*mem));
+
+	if (!mem)
+		return NULL;
+	strcpy(mem->indent_str, "");
+	mem->indent_level = 0;
+	return mem;
+}
+
+void free_indent_mem(struct indent_mem *mem)
+{
+	free(mem);
+}
+
+#define INDENT_STR_STEP 2
+
+void inc_indent(struct indent_mem *mem)
+{
+	if (mem->indent_level + INDENT_STR_STEP > INDENT_STR_MAXLEN)
+		return;
+	mem->indent_level += INDENT_STR_STEP;
+	memset(mem->indent_str, ' ', sizeof(mem->indent_str));
+	mem->indent_str[mem->indent_level] = '\0';
+}
+
+void dec_indent(struct indent_mem *mem)
+{
+	if (mem->indent_level - INDENT_STR_STEP < 0)
+		return;
+	mem->indent_level -= INDENT_STR_STEP;
+	mem->indent_str[mem->indent_level] = '\0';
+}
+
+void print_indent(struct indent_mem *mem)
+{
+	if (mem->indent_level)
+		printf("%s", mem->indent_str);
+}
+
+const char *proto_n2a(unsigned short id, char *buf, int len,
+		      const struct proto *proto_tb, size_t tb_len)
+{
+	int i;
+
+	id = ntohs(id);
+
+	for (i = 0; !numeric && i < tb_len; i++) {
+		if (proto_tb[i].id == id)
+			return proto_tb[i].name;
+	}
+
+	snprintf(buf, len, "[%d]", id);
+
+	return buf;
+}
+
+int proto_a2n(unsigned short *id, const char *buf,
+	      const struct proto *proto_tb, size_t tb_len)
+{
+	int i;
+
+	for (i = 0; i < tb_len; i++) {
+		if (strcasecmp(proto_tb[i].name, buf) == 0) {
+			*id = htons(proto_tb[i].id);
+			return 0;
+		}
+	}
+	if (get_be16(id, buf, 0))
+		return -1;
+
+	return 0;
+}
diff --git a/lib/utils_math.c b/lib/utils_math.c
new file mode 100644
index 0000000..9ef3dd6
--- /dev/null
+++ b/lib/utils_math.c
@@ -0,0 +1,123 @@
+// SPDX-License-Identifier: GPL-2.0+
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <math.h>
+#include <asm/types.h>
+
+#include "utils.h"
+
+/* See http://physics.nist.gov/cuu/Units/binary.html */
+static const struct rate_suffix {
+	const char *name;
+	double scale;
+} suffixes[] = {
+	{ "bit",	1. },
+	{ "Kibit",	1024. },
+	{ "kbit",	1000. },
+	{ "mibit",	1024.*1024. },
+	{ "mbit",	1000000. },
+	{ "gibit",	1024.*1024.*1024. },
+	{ "gbit",	1000000000. },
+	{ "tibit",	1024.*1024.*1024.*1024. },
+	{ "tbit",	1000000000000. },
+	{ "Bps",	8. },
+	{ "KiBps",	8.*1024. },
+	{ "KBps",	8000. },
+	{ "MiBps",	8.*1024*1024. },
+	{ "MBps",	8000000. },
+	{ "GiBps",	8.*1024.*1024.*1024. },
+	{ "GBps",	8000000000. },
+	{ "TiBps",	8.*1024.*1024.*1024.*1024. },
+	{ "TBps",	8000000000000. },
+	{ NULL }
+};
+
+int get_rate(unsigned int *rate, const char *str)
+{
+	char *p;
+	double bps = strtod(str, &p);
+	const struct rate_suffix *s;
+
+	if (p == str)
+		return -1;
+
+	for (s = suffixes; s->name; ++s) {
+		if (strcasecmp(s->name, p) == 0) {
+			bps *= s->scale;
+			p += strlen(p);
+			break;
+		}
+	}
+
+	if (*p)
+		return -1; /* unknown suffix */
+
+	bps /= 8; /* -> bytes per second */
+	*rate = bps;
+	/* detect if an overflow happened */
+	if (*rate != floor(bps))
+		return -1;
+	return 0;
+}
+
+int get_rate64(__u64 *rate, const char *str)
+{
+	char *p;
+	double bps = strtod(str, &p);
+	const struct rate_suffix *s;
+
+	if (p == str)
+		return -1;
+
+	for (s = suffixes; s->name; ++s) {
+		if (strcasecmp(s->name, p) == 0) {
+			bps *= s->scale;
+			p += strlen(p);
+			break;
+		}
+	}
+
+	if (*p)
+		return -1; /* unknown suffix */
+
+	bps /= 8; /* -> bytes per second */
+	*rate = bps;
+	return 0;
+}
+
+int get_size(unsigned int *size, const char *str)
+{
+	double sz;
+	char *p;
+
+	sz = strtod(str, &p);
+	if (p == str)
+		return -1;
+
+	if (*p) {
+		if (strcasecmp(p, "kb") == 0 || strcasecmp(p, "k") == 0)
+			sz *= 1024;
+		else if (strcasecmp(p, "gb") == 0 || strcasecmp(p, "g") == 0)
+			sz *= 1024*1024*1024;
+		else if (strcasecmp(p, "gbit") == 0)
+			sz *= 1024*1024*1024/8;
+		else if (strcasecmp(p, "mb") == 0 || strcasecmp(p, "m") == 0)
+			sz *= 1024*1024;
+		else if (strcasecmp(p, "mbit") == 0)
+			sz *= 1024*1024/8;
+		else if (strcasecmp(p, "kbit") == 0)
+			sz *= 1024/8;
+		else if (strcasecmp(p, "b") != 0)
+			return -1;
+	}
+
+	*size = sz;
+
+	/* detect if an overflow happened */
+	if (*size != floor(sz))
+		return -1;
+
+	return 0;
+}