Adding upstream version 1.2.6.upstream/1.2.6upstream

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

1 files changed, 876 insertions, 0 deletions

diff --git a/src/rule.c b/src/rule.c
new file mode 100644
index 0000000..a52012b
--- /dev/null
+++ b/src/rule.c
@@ -0,0 +1,876 @@
+/*
+ * (C) 2012-2013 by Pablo Neira Ayuso <pablo@netfilter.org>
+ *
+ * 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.
+ *
+ * This code has been sponsored by Sophos Astaro <http://www.sophos.com>
+ */
+#include "internal.h"
+
+#include <time.h>
+#include <endian.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <limits.h>
+#include <string.h>
+#include <netinet/in.h>
+#include <errno.h>
+#include <inttypes.h>
+#include <ctype.h>
+
+#include <libmnl/libmnl.h>
+#include <linux/netfilter/nfnetlink.h>
+#include <linux/netfilter/nf_tables.h>
+
+#include <libnftnl/rule.h>
+#include <libnftnl/set.h>
+#include <libnftnl/expr.h>
+
+EXPORT_SYMBOL(nftnl_rule_alloc);
+struct nftnl_rule *nftnl_rule_alloc(void)
+{
+	struct nftnl_rule *r;
+
+	r = calloc(1, sizeof(struct nftnl_rule));
+	if (r == NULL)
+		return NULL;
+
+	INIT_LIST_HEAD(&r->expr_list);
+
+	return r;
+}
+
+EXPORT_SYMBOL(nftnl_rule_free);
+void nftnl_rule_free(const struct nftnl_rule *r)
+{
+	struct nftnl_expr *e, *tmp;
+
+	list_for_each_entry_safe(e, tmp, &r->expr_list, head)
+		nftnl_expr_free(e);
+
+	if (r->flags & (1 << (NFTNL_RULE_TABLE)))
+		xfree(r->table);
+	if (r->flags & (1 << (NFTNL_RULE_CHAIN)))
+		xfree(r->chain);
+	if (r->flags & (1 << (NFTNL_RULE_USERDATA)))
+		xfree(r->user.data);
+
+	xfree(r);
+}
+
+EXPORT_SYMBOL(nftnl_rule_is_set);
+bool nftnl_rule_is_set(const struct nftnl_rule *r, uint16_t attr)
+{
+	return r->flags & (1 << attr);
+}
+
+EXPORT_SYMBOL(nftnl_rule_unset);
+void nftnl_rule_unset(struct nftnl_rule *r, uint16_t attr)
+{
+	if (!(r->flags & (1 << attr)))
+		return;
+
+	switch (attr) {
+	case NFTNL_RULE_TABLE:
+		xfree(r->table);
+		break;
+	case NFTNL_RULE_CHAIN:
+		xfree(r->chain);
+		break;
+	case NFTNL_RULE_HANDLE:
+	case NFTNL_RULE_COMPAT_PROTO:
+	case NFTNL_RULE_COMPAT_FLAGS:
+	case NFTNL_RULE_POSITION:
+	case NFTNL_RULE_FAMILY:
+	case NFTNL_RULE_ID:
+	case NFTNL_RULE_POSITION_ID:
+		break;
+	case NFTNL_RULE_USERDATA:
+		xfree(r->user.data);
+		break;
+	}
+
+	r->flags &= ~(1 << attr);
+}
+
+static uint32_t nftnl_rule_validate[NFTNL_RULE_MAX + 1] = {
+	[NFTNL_RULE_HANDLE]		= sizeof(uint64_t),
+	[NFTNL_RULE_COMPAT_PROTO]	= sizeof(uint32_t),
+	[NFTNL_RULE_COMPAT_FLAGS]	= sizeof(uint32_t),
+	[NFTNL_RULE_FAMILY]		= sizeof(uint32_t),
+	[NFTNL_RULE_POSITION]		= sizeof(uint64_t),
+	[NFTNL_RULE_ID]			= sizeof(uint32_t),
+	[NFTNL_RULE_POSITION_ID]	= sizeof(uint32_t),
+};
+
+EXPORT_SYMBOL(nftnl_rule_set_data);
+int nftnl_rule_set_data(struct nftnl_rule *r, uint16_t attr,
+			const void *data, uint32_t data_len)
+{
+	nftnl_assert_attr_exists(attr, NFTNL_RULE_MAX);
+	nftnl_assert_validate(data, nftnl_rule_validate, attr, data_len);
+
+	switch(attr) {
+	case NFTNL_RULE_TABLE:
+		if (r->flags & (1 << NFTNL_RULE_TABLE))
+			xfree(r->table);
+
+		r->table = strdup(data);
+		if (!r->table)
+			return -1;
+		break;
+	case NFTNL_RULE_CHAIN:
+		if (r->flags & (1 << NFTNL_RULE_CHAIN))
+			xfree(r->chain);
+
+		r->chain = strdup(data);
+		if (!r->chain)
+			return -1;
+		break;
+	case NFTNL_RULE_HANDLE:
+		memcpy(&r->handle, data, sizeof(r->handle));
+		break;
+	case NFTNL_RULE_COMPAT_PROTO:
+		memcpy(&r->compat.proto, data, sizeof(r->compat.proto));
+		break;
+	case NFTNL_RULE_COMPAT_FLAGS:
+		memcpy(&r->compat.flags, data, sizeof(r->compat.flags));
+		break;
+	case NFTNL_RULE_FAMILY:
+		memcpy(&r->family, data, sizeof(r->family));
+		break;
+	case NFTNL_RULE_POSITION:
+		memcpy(&r->position, data, sizeof(r->position));
+		break;
+	case NFTNL_RULE_USERDATA:
+		if (r->flags & (1 << NFTNL_RULE_USERDATA))
+			xfree(r->user.data);
+
+		r->user.data = malloc(data_len);
+		if (!r->user.data)
+			return -1;
+
+		memcpy(r->user.data, data, data_len);
+		r->user.len = data_len;
+		break;
+	case NFTNL_RULE_ID:
+		memcpy(&r->id, data, sizeof(r->id));
+		break;
+	case NFTNL_RULE_POSITION_ID:
+		memcpy(&r->position_id, data, sizeof(r->position_id));
+		break;
+	}
+	r->flags |= (1 << attr);
+	return 0;
+}
+
+int nftnl_rule_set(struct nftnl_rule *r, uint16_t attr, const void *data) __visible;
+int nftnl_rule_set(struct nftnl_rule *r, uint16_t attr, const void *data)
+{
+	return nftnl_rule_set_data(r, attr, data, nftnl_rule_validate[attr]);
+}
+
+EXPORT_SYMBOL(nftnl_rule_set_u32);
+void nftnl_rule_set_u32(struct nftnl_rule *r, uint16_t attr, uint32_t val)
+{
+	nftnl_rule_set_data(r, attr, &val, sizeof(uint32_t));
+}
+
+EXPORT_SYMBOL(nftnl_rule_set_u64);
+void nftnl_rule_set_u64(struct nftnl_rule *r, uint16_t attr, uint64_t val)
+{
+	nftnl_rule_set_data(r, attr, &val, sizeof(uint64_t));
+}
+
+EXPORT_SYMBOL(nftnl_rule_set_str);
+int nftnl_rule_set_str(struct nftnl_rule *r, uint16_t attr, const char *str)
+{
+	return nftnl_rule_set_data(r, attr, str, strlen(str) + 1);
+}
+
+EXPORT_SYMBOL(nftnl_rule_get_data);
+const void *nftnl_rule_get_data(const struct nftnl_rule *r, uint16_t attr,
+				   uint32_t *data_len)
+{
+	if (!(r->flags & (1 << attr)))
+		return NULL;
+
+	switch(attr) {
+	case NFTNL_RULE_FAMILY:
+		*data_len = sizeof(uint32_t);
+		return &r->family;
+	case NFTNL_RULE_TABLE:
+		*data_len = strlen(r->table) + 1;
+		return r->table;
+	case NFTNL_RULE_CHAIN:
+		*data_len = strlen(r->chain) + 1;
+		return r->chain;
+	case NFTNL_RULE_HANDLE:
+		*data_len = sizeof(uint64_t);
+		return &r->handle;
+	case NFTNL_RULE_COMPAT_PROTO:
+		*data_len = sizeof(uint32_t);
+		return &r->compat.proto;
+	case NFTNL_RULE_COMPAT_FLAGS:
+		*data_len = sizeof(uint32_t);
+		return &r->compat.flags;
+	case NFTNL_RULE_POSITION:
+		*data_len = sizeof(uint64_t);
+		return &r->position;
+	case NFTNL_RULE_USERDATA:
+		*data_len = r->user.len;
+		return r->user.data;
+	case NFTNL_RULE_ID:
+		*data_len = sizeof(uint32_t);
+		return &r->id;
+	case NFTNL_RULE_POSITION_ID:
+		*data_len = sizeof(uint32_t);
+		return &r->position_id;
+	}
+	return NULL;
+}
+
+EXPORT_SYMBOL(nftnl_rule_get);
+const void *nftnl_rule_get(const struct nftnl_rule *r, uint16_t attr)
+{
+	uint32_t data_len;
+	return nftnl_rule_get_data(r, attr, &data_len);
+}
+
+EXPORT_SYMBOL(nftnl_rule_get_str);
+const char *nftnl_rule_get_str(const struct nftnl_rule *r, uint16_t attr)
+{
+	return nftnl_rule_get(r, attr);
+}
+
+EXPORT_SYMBOL(nftnl_rule_get_u32);
+uint32_t nftnl_rule_get_u32(const struct nftnl_rule *r, uint16_t attr)
+{
+	uint32_t data_len;
+	const uint32_t *val = nftnl_rule_get_data(r, attr, &data_len);
+
+	nftnl_assert(val, attr, data_len == sizeof(uint32_t));
+
+	return val ? *val : 0;
+}
+
+EXPORT_SYMBOL(nftnl_rule_get_u64);
+uint64_t nftnl_rule_get_u64(const struct nftnl_rule *r, uint16_t attr)
+{
+	uint32_t data_len;
+	const uint64_t *val = nftnl_rule_get_data(r, attr, &data_len);
+
+	nftnl_assert(val, attr, data_len == sizeof(uint64_t));
+
+	return val ? *val : 0;
+}
+
+EXPORT_SYMBOL(nftnl_rule_get_u8);
+uint8_t nftnl_rule_get_u8(const struct nftnl_rule *r, uint16_t attr)
+{
+	uint32_t data_len;
+	const uint8_t *val = nftnl_rule_get_data(r, attr, &data_len);
+
+	nftnl_assert(val, attr, data_len == sizeof(uint8_t));
+
+	return val ? *val : 0;
+}
+
+EXPORT_SYMBOL(nftnl_rule_nlmsg_build_payload);
+void nftnl_rule_nlmsg_build_payload(struct nlmsghdr *nlh, struct nftnl_rule *r)
+{
+	struct nftnl_expr *expr;
+	struct nlattr *nest, *nest2;
+
+	if (r->flags & (1 << NFTNL_RULE_TABLE))
+		mnl_attr_put_strz(nlh, NFTA_RULE_TABLE, r->table);
+	if (r->flags & (1 << NFTNL_RULE_CHAIN))
+		mnl_attr_put_strz(nlh, NFTA_RULE_CHAIN, r->chain);
+	if (r->flags & (1 << NFTNL_RULE_HANDLE))
+		mnl_attr_put_u64(nlh, NFTA_RULE_HANDLE, htobe64(r->handle));
+	if (r->flags & (1 << NFTNL_RULE_POSITION))
+		mnl_attr_put_u64(nlh, NFTA_RULE_POSITION, htobe64(r->position));
+	if (r->flags & (1 << NFTNL_RULE_USERDATA)) {
+		mnl_attr_put(nlh, NFTA_RULE_USERDATA, r->user.len,
+			     r->user.data);
+	}
+
+	if (!list_empty(&r->expr_list)) {
+		nest = mnl_attr_nest_start(nlh, NFTA_RULE_EXPRESSIONS);
+		list_for_each_entry(expr, &r->expr_list, head) {
+			nest2 = mnl_attr_nest_start(nlh, NFTA_LIST_ELEM);
+			nftnl_expr_build_payload(nlh, expr);
+			mnl_attr_nest_end(nlh, nest2);
+		}
+		mnl_attr_nest_end(nlh, nest);
+	}
+
+	if (r->flags & (1 << NFTNL_RULE_COMPAT_PROTO) &&
+	    r->flags & (1 << NFTNL_RULE_COMPAT_FLAGS)) {
+
+		nest = mnl_attr_nest_start(nlh, NFTA_RULE_COMPAT);
+		mnl_attr_put_u32(nlh, NFTA_RULE_COMPAT_PROTO,
+				 htonl(r->compat.proto));
+		mnl_attr_put_u32(nlh, NFTA_RULE_COMPAT_FLAGS,
+				 htonl(r->compat.flags));
+		mnl_attr_nest_end(nlh, nest);
+	}
+	if (r->flags & (1 << NFTNL_RULE_ID))
+		mnl_attr_put_u32(nlh, NFTA_RULE_ID, htonl(r->id));
+	if (r->flags & (1 << NFTNL_RULE_POSITION_ID))
+		mnl_attr_put_u32(nlh, NFTA_RULE_POSITION_ID, htonl(r->position_id));
+}
+
+EXPORT_SYMBOL(nftnl_rule_add_expr);
+void nftnl_rule_add_expr(struct nftnl_rule *r, struct nftnl_expr *expr)
+{
+	list_add_tail(&expr->head, &r->expr_list);
+}
+
+EXPORT_SYMBOL(nftnl_rule_del_expr);
+void nftnl_rule_del_expr(struct nftnl_expr *expr)
+{
+	list_del(&expr->head);
+}
+
+static int nftnl_rule_parse_attr_cb(const struct nlattr *attr, void *data)
+{
+	const struct nlattr **tb = data;
+	int type = mnl_attr_get_type(attr);
+
+	if (mnl_attr_type_valid(attr, NFTA_RULE_MAX) < 0)
+		return MNL_CB_OK;
+
+	switch(type) {
+	case NFTA_RULE_TABLE:
+	case NFTA_RULE_CHAIN:
+		if (mnl_attr_validate(attr, MNL_TYPE_STRING) < 0)
+			abi_breakage();
+		break;
+	case NFTA_RULE_HANDLE:
+		if (mnl_attr_validate(attr, MNL_TYPE_U64) < 0)
+			abi_breakage();
+		break;
+	case NFTA_RULE_COMPAT:
+		if (mnl_attr_validate(attr, MNL_TYPE_NESTED) < 0)
+			abi_breakage();
+		break;
+	case NFTA_RULE_POSITION:
+		if (mnl_attr_validate(attr, MNL_TYPE_U64) < 0)
+			abi_breakage();
+		break;
+	case NFTA_RULE_USERDATA:
+		if (mnl_attr_validate(attr, MNL_TYPE_BINARY) < 0)
+			abi_breakage();
+		break;
+	case NFTA_RULE_ID:
+	case NFTA_RULE_POSITION_ID:
+		if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0)
+			abi_breakage();
+		break;
+	}
+
+	tb[type] = attr;
+	return MNL_CB_OK;
+}
+
+static int nftnl_rule_parse_expr(struct nlattr *nest, struct nftnl_rule *r)
+{
+	struct nftnl_expr *expr;
+	struct nlattr *attr;
+
+	mnl_attr_for_each_nested(attr, nest) {
+		if (mnl_attr_get_type(attr) != NFTA_LIST_ELEM)
+			return -1;
+
+		expr = nftnl_expr_parse(attr);
+		if (expr == NULL)
+			return -1;
+
+		list_add_tail(&expr->head, &r->expr_list);
+	}
+	return 0;
+}
+
+static int nftnl_rule_parse_compat_cb(const struct nlattr *attr, void *data)
+{
+	const struct nlattr **tb = data;
+	int type = mnl_attr_get_type(attr);
+
+	if (mnl_attr_type_valid(attr, NFTA_RULE_COMPAT_MAX) < 0)
+		return MNL_CB_OK;
+
+	switch(type) {
+	case NFTA_RULE_COMPAT_PROTO:
+	case NFTA_RULE_COMPAT_FLAGS:
+		if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0)
+			abi_breakage();
+		break;
+	}
+
+	tb[type] = attr;
+	return MNL_CB_OK;
+}
+
+static int nftnl_rule_parse_compat(struct nlattr *nest, struct nftnl_rule *r)
+{
+	struct nlattr *tb[NFTA_RULE_COMPAT_MAX+1] = {};
+
+	if (mnl_attr_parse_nested(nest, nftnl_rule_parse_compat_cb, tb) < 0)
+		return -1;
+
+	if (tb[NFTA_RULE_COMPAT_PROTO]) {
+		r->compat.proto =
+			ntohl(mnl_attr_get_u32(tb[NFTA_RULE_COMPAT_PROTO]));
+		r->flags |= (1 << NFTNL_RULE_COMPAT_PROTO);
+	}
+	if (tb[NFTA_RULE_COMPAT_FLAGS]) {
+		r->compat.flags =
+			ntohl(mnl_attr_get_u32(tb[NFTA_RULE_COMPAT_FLAGS]));
+		r->flags |= (1 << NFTNL_RULE_COMPAT_FLAGS);
+	}
+	return 0;
+}
+
+EXPORT_SYMBOL(nftnl_rule_nlmsg_parse);
+int nftnl_rule_nlmsg_parse(const struct nlmsghdr *nlh, struct nftnl_rule *r)
+{
+	struct nlattr *tb[NFTA_RULE_MAX+1] = {};
+	struct nfgenmsg *nfg = mnl_nlmsg_get_payload(nlh);
+	int ret;
+
+	if (mnl_attr_parse(nlh, sizeof(*nfg), nftnl_rule_parse_attr_cb, tb) < 0)
+		return -1;
+
+	if (tb[NFTA_RULE_TABLE]) {
+		if (r->flags & (1 << NFTNL_RULE_TABLE))
+			xfree(r->table);
+		r->table = strdup(mnl_attr_get_str(tb[NFTA_RULE_TABLE]));
+		if (!r->table)
+			return -1;
+		r->flags |= (1 << NFTNL_RULE_TABLE);
+	}
+	if (tb[NFTA_RULE_CHAIN]) {
+		if (r->flags & (1 << NFTNL_RULE_CHAIN))
+			xfree(r->chain);
+		r->chain = strdup(mnl_attr_get_str(tb[NFTA_RULE_CHAIN]));
+		if (!r->chain)
+			return -1;
+		r->flags |= (1 << NFTNL_RULE_CHAIN);
+	}
+	if (tb[NFTA_RULE_HANDLE]) {
+		r->handle = be64toh(mnl_attr_get_u64(tb[NFTA_RULE_HANDLE]));
+		r->flags |= (1 << NFTNL_RULE_HANDLE);
+	}
+	if (tb[NFTA_RULE_EXPRESSIONS]) {
+		ret = nftnl_rule_parse_expr(tb[NFTA_RULE_EXPRESSIONS], r);
+		if (ret < 0)
+			return ret;
+	}
+	if (tb[NFTA_RULE_COMPAT]) {
+		ret = nftnl_rule_parse_compat(tb[NFTA_RULE_COMPAT], r);
+		if (ret < 0)
+			return ret;
+	}
+	if (tb[NFTA_RULE_POSITION]) {
+		r->position = be64toh(mnl_attr_get_u64(tb[NFTA_RULE_POSITION]));
+		r->flags |= (1 << NFTNL_RULE_POSITION);
+	}
+	if (tb[NFTA_RULE_USERDATA]) {
+		const void *udata =
+			mnl_attr_get_payload(tb[NFTA_RULE_USERDATA]);
+
+		if (r->flags & (1 << NFTNL_RULE_USERDATA))
+			xfree(r->user.data);
+
+		r->user.len = mnl_attr_get_payload_len(tb[NFTA_RULE_USERDATA]);
+
+		r->user.data = malloc(r->user.len);
+		if (r->user.data == NULL)
+			return -1;
+
+		memcpy(r->user.data, udata, r->user.len);
+		r->flags |= (1 << NFTNL_RULE_USERDATA);
+	}
+	if (tb[NFTA_RULE_ID]) {
+		r->id = ntohl(mnl_attr_get_u32(tb[NFTA_RULE_ID]));
+		r->flags |= (1 << NFTNL_RULE_ID);
+	}
+	if (tb[NFTA_RULE_POSITION_ID]) {
+		r->position_id = ntohl(mnl_attr_get_u32(tb[NFTA_RULE_POSITION_ID]));
+		r->flags |= (1 << NFTNL_RULE_POSITION_ID);
+	}
+
+	r->family = nfg->nfgen_family;
+	r->flags |= (1 << NFTNL_RULE_FAMILY);
+
+	return 0;
+}
+
+static int nftnl_rule_do_parse(struct nftnl_rule *r, enum nftnl_parse_type type,
+			     const void *data, struct nftnl_parse_err *err,
+			     enum nftnl_parse_input input)
+{
+	int ret;
+	struct nftnl_parse_err perr = {};
+
+	switch (type) {
+	case NFTNL_PARSE_JSON:
+	case NFTNL_PARSE_XML:
+	default:
+		ret = -1;
+		errno = EOPNOTSUPP;
+		break;
+	}
+	if (err != NULL)
+		*err = perr;
+
+	return ret;
+}
+
+EXPORT_SYMBOL(nftnl_rule_parse);
+int nftnl_rule_parse(struct nftnl_rule *r, enum nftnl_parse_type type,
+		   const char *data, struct nftnl_parse_err *err)
+{
+	return nftnl_rule_do_parse(r, type, data, err, NFTNL_PARSE_BUFFER);
+}
+
+EXPORT_SYMBOL(nftnl_rule_parse_file);
+int nftnl_rule_parse_file(struct nftnl_rule *r, enum nftnl_parse_type type,
+			FILE *fp, struct nftnl_parse_err *err)
+{
+	return nftnl_rule_do_parse(r, type, fp, err, NFTNL_PARSE_FILE);
+}
+
+static int nftnl_rule_snprintf_default(char *buf, size_t remain,
+				       const struct nftnl_rule *r,
+				       uint32_t type, uint32_t flags)
+{
+	struct nftnl_expr *expr;
+	int ret, offset = 0, i;
+	const char *sep = "";
+
+	if (r->flags & (1 << NFTNL_RULE_FAMILY)) {
+		ret = snprintf(buf + offset, remain, "%s%s", sep,
+			       nftnl_family2str(r->family));
+		SNPRINTF_BUFFER_SIZE(ret, remain, offset);
+		sep = " ";
+	}
+
+	if (r->flags & (1 << NFTNL_RULE_TABLE)) {
+		ret = snprintf(buf + offset, remain, "%s%s", sep,
+			       r->table);
+		SNPRINTF_BUFFER_SIZE(ret, remain, offset);
+		sep = " ";
+	}
+
+	if (r->flags & (1 << NFTNL_RULE_CHAIN)) {
+		ret = snprintf(buf + offset, remain, "%s%s", sep,
+			       r->chain);
+		SNPRINTF_BUFFER_SIZE(ret, remain, offset);
+		sep = " ";
+	}
+	if (r->flags & (1 << NFTNL_RULE_HANDLE)) {
+		ret = snprintf(buf + offset, remain, "%s%" PRIu64, sep,
+			       r->handle);
+		SNPRINTF_BUFFER_SIZE(ret, remain, offset);
+		sep = " ";
+	}
+
+	if (r->flags & (1 << NFTNL_RULE_POSITION)) {
+		ret = snprintf(buf + offset, remain, "%s%" PRIu64, sep,
+			       r->position);
+		SNPRINTF_BUFFER_SIZE(ret, remain, offset);
+		sep = " ";
+	}
+
+	if (r->flags & (1 << NFTNL_RULE_ID)) {
+		ret = snprintf(buf + offset, remain, "%s%u", sep, r->id);
+		SNPRINTF_BUFFER_SIZE(ret, remain, offset);
+		sep = " ";
+	}
+
+	if (r->flags & (1 << NFTNL_RULE_POSITION_ID)) {
+		ret = snprintf(buf + offset, remain, "%s%u", sep,
+			       r->position_id);
+		SNPRINTF_BUFFER_SIZE(ret, remain, offset);
+		sep = " ";
+	}
+
+	ret = snprintf(buf + offset, remain, "\n");
+	SNPRINTF_BUFFER_SIZE(ret, remain, offset);
+
+	list_for_each_entry(expr, &r->expr_list, head) {
+		ret = snprintf(buf + offset, remain, "  [ %s ", expr->ops->name);
+		SNPRINTF_BUFFER_SIZE(ret, remain, offset);
+
+		ret = nftnl_expr_snprintf(buf + offset, remain, expr,
+					     type, flags);
+		SNPRINTF_BUFFER_SIZE(ret, remain, offset);
+
+		ret = snprintf(buf + offset, remain, "]\n");
+		SNPRINTF_BUFFER_SIZE(ret, remain, offset);
+	}
+
+	if (r->user.len) {
+		ret = snprintf(buf + offset, remain, "  userdata = { ");
+		SNPRINTF_BUFFER_SIZE(ret, remain, offset);
+
+		for (i = 0; i < r->user.len; i++) {
+			char *c = r->user.data;
+
+			ret = snprintf(buf + offset, remain,
+				       isprint(c[i]) ? "%c" : "\\x%02hhx",
+				       c[i]);
+			SNPRINTF_BUFFER_SIZE(ret, remain, offset);
+		}
+
+		ret = snprintf(buf + offset, remain, " }");
+		SNPRINTF_BUFFER_SIZE(ret, remain, offset);
+
+	}
+
+	return offset;
+}
+
+static int nftnl_rule_cmd_snprintf(char *buf, size_t remain,
+				   const struct nftnl_rule *r, uint32_t cmd,
+				   uint32_t type, uint32_t flags)
+{
+	uint32_t inner_flags = flags;
+	int ret, offset = 0;
+
+	inner_flags &= ~NFTNL_OF_EVENT_ANY;
+
+	if (type != NFTNL_OUTPUT_DEFAULT)
+		return -1;
+
+	ret = nftnl_rule_snprintf_default(buf + offset, remain, r, type,
+					inner_flags);
+	SNPRINTF_BUFFER_SIZE(ret, remain, offset);
+	return offset;
+}
+
+EXPORT_SYMBOL(nftnl_rule_snprintf);
+int nftnl_rule_snprintf(char *buf, size_t size, const struct nftnl_rule *r,
+			uint32_t type, uint32_t flags)
+{
+	if (size)
+		buf[0] = '\0';
+
+	return nftnl_rule_cmd_snprintf(buf, size, r, nftnl_flag2cmd(flags), type,
+				     flags);
+}
+
+static int nftnl_rule_do_snprintf(char *buf, size_t size, const void *r,
+				  uint32_t cmd, uint32_t type, uint32_t flags)
+{
+	return nftnl_rule_snprintf(buf, size, r, type, flags);
+}
+
+EXPORT_SYMBOL(nftnl_rule_fprintf);
+int nftnl_rule_fprintf(FILE *fp, const struct nftnl_rule *r, uint32_t type,
+		       uint32_t flags)
+{
+	return nftnl_fprintf(fp, r, NFTNL_CMD_UNSPEC, type, flags,
+			   nftnl_rule_do_snprintf);
+}
+
+EXPORT_SYMBOL(nftnl_expr_foreach);
+int nftnl_expr_foreach(struct nftnl_rule *r,
+                          int (*cb)(struct nftnl_expr *e, void *data),
+                          void *data)
+{
+       struct nftnl_expr *cur, *tmp;
+       int ret;
+
+       list_for_each_entry_safe(cur, tmp, &r->expr_list, head) {
+               ret = cb(cur, data);
+               if (ret < 0)
+                       return ret;
+       }
+       return 0;
+}
+
+struct nftnl_expr_iter {
+	const struct nftnl_rule	*r;
+	struct nftnl_expr	*cur;
+};
+
+static void nftnl_expr_iter_init(const struct nftnl_rule *r,
+				 struct nftnl_expr_iter *iter)
+{
+	iter->r = r;
+	if (list_empty(&r->expr_list))
+		iter->cur = NULL;
+	else
+		iter->cur = list_entry(r->expr_list.next, struct nftnl_expr,
+				       head);
+}
+
+EXPORT_SYMBOL(nftnl_expr_iter_create);
+struct nftnl_expr_iter *nftnl_expr_iter_create(const struct nftnl_rule *r)
+{
+	struct nftnl_expr_iter *iter;
+
+	iter = calloc(1, sizeof(struct nftnl_expr_iter));
+	if (iter == NULL)
+		return NULL;
+
+	nftnl_expr_iter_init(r, iter);
+
+	return iter;
+}
+
+EXPORT_SYMBOL(nftnl_expr_iter_next);
+struct nftnl_expr *nftnl_expr_iter_next(struct nftnl_expr_iter *iter)
+{
+	struct nftnl_expr *expr = iter->cur;
+
+	if (expr == NULL)
+		return NULL;
+
+	/* get next expression, if any */
+	iter->cur = list_entry(iter->cur->head.next, struct nftnl_expr, head);
+	if (&iter->cur->head == iter->r->expr_list.next)
+		return NULL;
+
+	return expr;
+}
+
+EXPORT_SYMBOL(nftnl_expr_iter_destroy);
+void nftnl_expr_iter_destroy(struct nftnl_expr_iter *iter)
+{
+	xfree(iter);
+}
+
+struct nftnl_rule_list {
+	struct list_head list;
+};
+
+EXPORT_SYMBOL(nftnl_rule_list_alloc);
+struct nftnl_rule_list *nftnl_rule_list_alloc(void)
+{
+	struct nftnl_rule_list *list;
+
+	list = calloc(1, sizeof(struct nftnl_rule_list));
+	if (list == NULL)
+		return NULL;
+
+	INIT_LIST_HEAD(&list->list);
+
+	return list;
+}
+
+EXPORT_SYMBOL(nftnl_rule_list_free);
+void nftnl_rule_list_free(struct nftnl_rule_list *list)
+{
+	struct nftnl_rule *r, *tmp;
+
+	list_for_each_entry_safe(r, tmp, &list->list, head) {
+		list_del(&r->head);
+		nftnl_rule_free(r);
+	}
+	xfree(list);
+}
+
+EXPORT_SYMBOL(nftnl_rule_list_is_empty);
+int nftnl_rule_list_is_empty(const struct nftnl_rule_list *list)
+{
+	return list_empty(&list->list);
+}
+
+EXPORT_SYMBOL(nftnl_rule_list_add);
+void nftnl_rule_list_add(struct nftnl_rule *r, struct nftnl_rule_list *list)
+{
+	list_add(&r->head, &list->list);
+}
+
+EXPORT_SYMBOL(nftnl_rule_list_insert_at);
+void nftnl_rule_list_insert_at(struct nftnl_rule *r, struct nftnl_rule *pos)
+{
+	list_add(&r->head, &pos->head);
+}
+
+EXPORT_SYMBOL(nftnl_rule_list_add_tail);
+void nftnl_rule_list_add_tail(struct nftnl_rule *r, struct nftnl_rule_list *list)
+{
+	list_add_tail(&r->head, &list->list);
+}
+
+EXPORT_SYMBOL(nftnl_rule_list_del);
+void nftnl_rule_list_del(struct nftnl_rule *r)
+{
+	list_del(&r->head);
+}
+
+EXPORT_SYMBOL(nftnl_rule_list_foreach);
+int nftnl_rule_list_foreach(struct nftnl_rule_list *rule_list,
+			  int (*cb)(struct nftnl_rule *r, void *data),
+			  void *data)
+{
+	struct nftnl_rule *cur, *tmp;
+	int ret;
+
+	list_for_each_entry_safe(cur, tmp, &rule_list->list, head) {
+		ret = cb(cur, data);
+		if (ret < 0)
+			return ret;
+	}
+	return 0;
+}
+
+struct nftnl_rule_list_iter {
+	const struct nftnl_rule_list	*list;
+	struct nftnl_rule		*cur;
+};
+
+EXPORT_SYMBOL(nftnl_rule_list_iter_create);
+struct nftnl_rule_list_iter *
+nftnl_rule_list_iter_create(const struct nftnl_rule_list *l)
+{
+	struct nftnl_rule_list_iter *iter;
+
+	iter = calloc(1, sizeof(struct nftnl_rule_list_iter));
+	if (iter == NULL)
+		return NULL;
+
+	iter->list = l;
+	if (nftnl_rule_list_is_empty(l))
+		iter->cur = NULL;
+	else
+		iter->cur = list_entry(l->list.next, struct nftnl_rule, head);
+
+	return iter;
+}
+
+EXPORT_SYMBOL(nftnl_rule_list_iter_cur);
+struct nftnl_rule *nftnl_rule_list_iter_cur(struct nftnl_rule_list_iter *iter)
+{
+	return iter->cur;
+}
+
+EXPORT_SYMBOL(nftnl_rule_list_iter_next);
+struct nftnl_rule *nftnl_rule_list_iter_next(struct nftnl_rule_list_iter *iter)
+{
+	struct nftnl_rule *r = iter->cur;
+
+	if (r == NULL)
+		return NULL;
+
+	/* get next rule, if any */
+	iter->cur = list_entry(iter->cur->head.next, struct nftnl_rule, head);
+	if (&iter->cur->head == iter->list->list.next)
+		return NULL;
+
+	return r;
+}
+
+EXPORT_SYMBOL(nftnl_rule_list_iter_destroy);
+void nftnl_rule_list_iter_destroy(const struct nftnl_rule_list_iter *iter)
+{
+	xfree(iter);
+}