1 files changed, 266 insertions, 0 deletions
diff --git a/tc/f_bpf.c b/tc/f_bpf.c
new file mode 100644
index 0000000..a6d4875
--- /dev/null
+++ b/tc/f_bpf.c
@@ -0,0 +1,266 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * f_bpf.c	BPF-based Classifier
+ *
+ * Authors:	Daniel Borkmann <daniel@iogearbox.net>
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include <linux/bpf.h>
+
+#include "utils.h"
+
+#include "tc_util.h"
+#include "bpf_util.h"
+
+static const enum bpf_prog_type bpf_type = BPF_PROG_TYPE_SCHED_CLS;
+
+static void explain(void)
+{
+	fprintf(stderr,
+		"Usage: ... bpf ...\n"
+		"\n"
+		"BPF use case:\n"
+		" bytecode BPF_BYTECODE\n"
+		" bytecode-file FILE\n"
+		"\n"
+		"eBPF use case:\n"
+		" object-file FILE [ section CLS_NAME ] [ export UDS_FILE ]"
+		" [ verbose ] [ direct-action ] [ skip_hw | skip_sw ]\n"
+		" object-pinned FILE [ direct-action ] [ skip_hw | skip_sw ]\n"
+		"\n"
+		"Common remaining options:\n"
+		" [ action ACTION_SPEC ]\n"
+		" [ classid CLASSID ]\n"
+		"\n"
+		"Where BPF_BYTECODE := \'s,c t f k,c t f k,c t f k,...\'\n"
+		"c,t,f,k and s are decimals; s denotes number of 4-tuples\n"
+		"\n"
+		"Where FILE points to a file containing the BPF_BYTECODE string,\n"
+		"an ELF file containing eBPF map definitions and bytecode, or a\n"
+		"pinned eBPF program.\n"
+		"\n"
+		"Where CLS_NAME refers to the section name containing the\n"
+		"classifier (default \'%s\').\n"
+		"\n"
+		"Where UDS_FILE points to a unix domain socket file in order\n"
+		"to hand off control of all created eBPF maps to an agent.\n"
+		"\n"
+		"ACTION_SPEC := ... look at individual actions\n"
+		"NOTE: CLASSID is parsed as hexadecimal input.\n",
+		bpf_prog_to_default_section(bpf_type));
+}
+
+static void bpf_cbpf_cb(void *nl, const struct sock_filter *ops, int ops_len)
+{
+	addattr16(nl, MAX_MSG, TCA_BPF_OPS_LEN, ops_len);
+	addattr_l(nl, MAX_MSG, TCA_BPF_OPS, ops,
+		  ops_len * sizeof(struct sock_filter));
+}
+
+static void bpf_ebpf_cb(void *nl, int fd, const char *annotation)
+{
+	addattr32(nl, MAX_MSG, TCA_BPF_FD, fd);
+	addattrstrz(nl, MAX_MSG, TCA_BPF_NAME, annotation);
+}
+
+static const struct bpf_cfg_ops bpf_cb_ops = {
+	.cbpf_cb = bpf_cbpf_cb,
+	.ebpf_cb = bpf_ebpf_cb,
+};
+
+static int bpf_parse_opt(struct filter_util *qu, char *handle,
+			 int argc, char **argv, struct nlmsghdr *n)
+{
+	const char *bpf_obj = NULL, *bpf_uds_name = NULL;
+	struct tcmsg *t = NLMSG_DATA(n);
+	unsigned int bpf_gen_flags = 0;
+	unsigned int bpf_flags = 0;
+	struct bpf_cfg_in cfg = {};
+	bool seen_run = false;
+	bool skip_sw = false;
+	struct rtattr *tail;
+	int ret = 0;
+
+	if (handle) {
+		if (get_u32(&t->tcm_handle, handle, 0)) {
+			fprintf(stderr, "Illegal \"handle\"\n");
+			return -1;
+		}
+	}
+
+	if (argc == 0)
+		return 0;
+
+	tail = (struct rtattr *)(((void *)n) + NLMSG_ALIGN(n->nlmsg_len));
+	addattr_l(n, MAX_MSG, TCA_OPTIONS, NULL, 0);
+
+	while (argc > 0) {
+		if (matches(*argv, "run") == 0) {
+			NEXT_ARG();
+
+			if (seen_run)
+				duparg("run", *argv);
+opt_bpf:
+			seen_run = true;
+			cfg.type = bpf_type;
+			cfg.argc = argc;
+			cfg.argv = argv;
+
+			if (bpf_parse_common(&cfg, &bpf_cb_ops) < 0) {
+				fprintf(stderr,
+					"Unable to parse bpf command line\n");
+				return -1;
+			}
+
+			argc = cfg.argc;
+			argv = cfg.argv;
+
+			bpf_obj = cfg.object;
+			bpf_uds_name = cfg.uds;
+		} else if (matches(*argv, "classid") == 0 ||
+			   matches(*argv, "flowid") == 0) {
+			unsigned int classid;
+
+			NEXT_ARG();
+			if (get_tc_classid(&classid, *argv)) {
+				fprintf(stderr, "Illegal \"classid\"\n");
+				return -1;
+			}
+			addattr32(n, MAX_MSG, TCA_BPF_CLASSID, classid);
+		} else if (matches(*argv, "direct-action") == 0 ||
+			   matches(*argv, "da") == 0) {
+			bpf_flags |= TCA_BPF_FLAG_ACT_DIRECT;
+		} else if (matches(*argv, "skip_hw") == 0) {
+			bpf_gen_flags |= TCA_CLS_FLAGS_SKIP_HW;
+		} else if (matches(*argv, "skip_sw") == 0) {
+			bpf_gen_flags |= TCA_CLS_FLAGS_SKIP_SW;
+			skip_sw = true;
+		} else if (matches(*argv, "action") == 0) {
+			NEXT_ARG();
+			if (parse_action(&argc, &argv, TCA_BPF_ACT, n)) {
+				fprintf(stderr, "Illegal \"action\"\n");
+				return -1;
+			}
+			continue;
+		} else if (matches(*argv, "police") == 0) {
+			NEXT_ARG();
+			if (parse_police(&argc, &argv, TCA_BPF_POLICE, n)) {
+				fprintf(stderr, "Illegal \"police\"\n");
+				return -1;
+			}
+			continue;
+		} else if (matches(*argv, "help") == 0) {
+			explain();
+			return -1;
+		} else {
+			if (!seen_run)
+				goto opt_bpf;
+
+			fprintf(stderr, "What is \"%s\"?\n", *argv);
+			explain();
+			return -1;
+		}
+
+		NEXT_ARG_FWD();
+	}
+
+	if (skip_sw)
+		cfg.ifindex = t->tcm_ifindex;
+	if (bpf_load_common(&cfg, &bpf_cb_ops, n) < 0) {
+		fprintf(stderr, "Unable to load program\n");
+		return -1;
+	}
+
+	if (bpf_gen_flags)
+		addattr32(n, MAX_MSG, TCA_BPF_FLAGS_GEN, bpf_gen_flags);
+	if (bpf_flags)
+		addattr32(n, MAX_MSG, TCA_BPF_FLAGS, bpf_flags);
+
+	tail->rta_len = (((void *)n) + n->nlmsg_len) - (void *)tail;
+
+	if (bpf_uds_name)
+		ret = bpf_send_map_fds(bpf_uds_name, bpf_obj);
+
+	return ret;
+}
+
+static int bpf_print_opt(struct filter_util *qu, FILE *f,
+			 struct rtattr *opt, __u32 handle)
+{
+	struct rtattr *tb[TCA_BPF_MAX + 1];
+	int dump_ok = 0;
+
+	if (opt == NULL)
+		return 0;
+
+	parse_rtattr_nested(tb, TCA_BPF_MAX, opt);
+
+	if (handle)
+		print_0xhex(PRINT_ANY, "handle", "handle %#llx ", handle);
+
+	if (tb[TCA_BPF_CLASSID]) {
+		SPRINT_BUF(b1);
+		print_string(PRINT_ANY, "flowid", "flowid %s ",
+			sprint_tc_classid(rta_getattr_u32(tb[TCA_BPF_CLASSID]), b1));
+	}
+
+	if (tb[TCA_BPF_NAME])
+		print_string(PRINT_ANY, "bpf_name", "%s ",
+			     rta_getattr_str(tb[TCA_BPF_NAME]));
+
+	if (tb[TCA_BPF_FLAGS]) {
+		unsigned int flags = rta_getattr_u32(tb[TCA_BPF_FLAGS]);
+
+		if (flags & TCA_BPF_FLAG_ACT_DIRECT)
+			print_bool(PRINT_ANY,
+				   "direct-action", "direct-action ", true);
+	}
+
+	if (tb[TCA_BPF_FLAGS_GEN]) {
+		unsigned int flags =
+			rta_getattr_u32(tb[TCA_BPF_FLAGS_GEN]);
+
+		if (flags & TCA_CLS_FLAGS_SKIP_HW)
+			print_bool(PRINT_ANY, "skip_hw", "skip_hw ", true);
+		if (flags & TCA_CLS_FLAGS_SKIP_SW)
+			print_bool(PRINT_ANY, "skip_sw", "skip_sw ", true);
+		if (flags & TCA_CLS_FLAGS_IN_HW)
+			print_bool(PRINT_ANY, "in_hw", "in_hw ", true);
+		else if (flags & TCA_CLS_FLAGS_NOT_IN_HW)
+			print_bool(PRINT_ANY,
+				   "not_in_hw", "not_in_hw ", true);
+	}
+
+	if (tb[TCA_BPF_OPS] && tb[TCA_BPF_OPS_LEN])
+		bpf_print_ops(tb[TCA_BPF_OPS],
+			      rta_getattr_u16(tb[TCA_BPF_OPS_LEN]));
+
+	if (tb[TCA_BPF_ID])
+		dump_ok = bpf_dump_prog_info(f, rta_getattr_u32(tb[TCA_BPF_ID]));
+	if (!dump_ok && tb[TCA_BPF_TAG]) {
+		SPRINT_BUF(b);
+
+		print_string(PRINT_ANY, "tag", "tag %s ",
+			     hexstring_n2a(RTA_DATA(tb[TCA_BPF_TAG]),
+			     RTA_PAYLOAD(tb[TCA_BPF_TAG]), b, sizeof(b)));
+	}
+
+	if (tb[TCA_BPF_POLICE]) {
+		print_nl();
+		tc_print_police(f, tb[TCA_BPF_POLICE]);
+	}
+
+	if (tb[TCA_BPF_ACT])
+		tc_print_action(f, tb[TCA_BPF_ACT], 0);
+
+	return 0;
+}
+
+struct filter_util bpf_filter_util = {
+	.id		= "bpf",
+	.parse_fopt	= bpf_parse_opt,
+	.print_fopt	= bpf_print_opt,
+};