[linux-2.6-block.git] / samples / bpf / xdp_redirect_user.c

// SPDX-License-Identifier: GPL-2.0-only
/* Copyright (c) 2016 John Fastabend <john.r.fastabend@intel.com>
 */
#include <linux/bpf.h>
#include <linux/if_link.h>
#include <assert.h>
#include <errno.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <string.h>
#include <net/if.h>
#include <unistd.h>
#include <libgen.h>
#include <sys/resource.h>

#include "bpf_util.h"
#include <bpf/bpf.h>
#include <bpf/libbpf.h>

static int ifindex_in;
static int ifindex_out;
static bool ifindex_out_xdp_dummy_attached = true;
static __u32 prog_id;
static __u32 dummy_prog_id;

static __u32 xdp_flags = XDP_FLAGS_UPDATE_IF_NOEXIST;
static int rxcnt_map_fd;

static void int_exit(int sig)
{
	__u32 curr_prog_id = 0;

	if (bpf_get_link_xdp_id(ifindex_in, &curr_prog_id, xdp_flags)) {
		printf("bpf_get_link_xdp_id failed\n");
		exit(1);
	}
	if (prog_id == curr_prog_id)
		bpf_set_link_xdp_fd(ifindex_in, -1, xdp_flags);
	else if (!curr_prog_id)
		printf("couldn't find a prog id on iface IN\n");
	else
		printf("program on iface IN changed, not removing\n");

	if (ifindex_out_xdp_dummy_attached) {
		curr_prog_id = 0;
		if (bpf_get_link_xdp_id(ifindex_out, &curr_prog_id,
					xdp_flags)) {
			printf("bpf_get_link_xdp_id failed\n");
			exit(1);
		}
		if (dummy_prog_id == curr_prog_id)
			bpf_set_link_xdp_fd(ifindex_out, -1, xdp_flags);
		else if (!curr_prog_id)
			printf("couldn't find a prog id on iface OUT\n");
		else
			printf("program on iface OUT changed, not removing\n");
	}
	exit(0);
}

static void poll_stats(int interval, int ifindex)
{
	unsigned int nr_cpus = bpf_num_possible_cpus();
	__u64 values[nr_cpus], prev[nr_cpus];

	memset(prev, 0, sizeof(prev));

	while (1) {
		__u64 sum = 0;
		__u32 key = 0;
		int i;

		sleep(interval);
		assert(bpf_map_lookup_elem(rxcnt_map_fd, &key, values) == 0);
		for (i = 0; i < nr_cpus; i++)
			sum += (values[i] - prev[i]);
		if (sum)
			printf("ifindex %i: %10llu pkt/s\n",
			       ifindex, sum / interval);
		memcpy(prev, values, sizeof(values));
	}
}

static void usage(const char *prog)
{
	fprintf(stderr,
		"usage: %s [OPTS] <IFNAME|IFINDEX>_IN <IFNAME|IFINDEX>_OUT\n\n"
		"OPTS:\n"
		"    -S    use skb-mode\n"
		"    -N    enforce native mode\n"
		"    -F    force loading prog\n",
		prog);
}


int main(int argc, char **argv)
{
	struct bpf_prog_load_attr prog_load_attr = {
		.prog_type	= BPF_PROG_TYPE_XDP,
	};
	struct bpf_program *prog, *dummy_prog;
	int prog_fd, tx_port_map_fd, opt;
	struct bpf_prog_info info = {};
	__u32 info_len = sizeof(info);
	const char *optstr = "FSN";
	struct bpf_object *obj;
	char filename[256];
	int dummy_prog_fd;
	int ret, key = 0;

	while ((opt = getopt(argc, argv, optstr)) != -1) {
		switch (opt) {
		case 'S':
			xdp_flags |= XDP_FLAGS_SKB_MODE;
			break;
		case 'N':
			/* default, set below */
			break;
		case 'F':
			xdp_flags &= ~XDP_FLAGS_UPDATE_IF_NOEXIST;
			break;
		default:
			usage(basename(argv[0]));
			return 1;
		}
	}

	if (!(xdp_flags & XDP_FLAGS_SKB_MODE))
		xdp_flags |= XDP_FLAGS_DRV_MODE;

	if (optind == argc) {
		printf("usage: %s <IFNAME|IFINDEX>_IN <IFNAME|IFINDEX>_OUT\n", argv[0]);
		return 1;
	}

	ifindex_in = if_nametoindex(argv[optind]);
	if (!ifindex_in)
		ifindex_in = strtoul(argv[optind], NULL, 0);

	ifindex_out = if_nametoindex(argv[optind + 1]);
	if (!ifindex_out)
		ifindex_out = strtoul(argv[optind + 1], NULL, 0);

	printf("input: %d output: %d\n", ifindex_in, ifindex_out);

	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
	prog_load_attr.file = filename;

	if (bpf_prog_load_xattr(&prog_load_attr, &obj, &prog_fd))
		return 1;

	prog = bpf_program__next(NULL, obj);
	dummy_prog = bpf_program__next(prog, obj);
	if (!prog || !dummy_prog) {
		printf("finding a prog in obj file failed\n");
		return 1;
	}
	/* bpf_prog_load_xattr gives us the pointer to first prog's fd,
	 * so we're missing only the fd for dummy prog
	 */
	dummy_prog_fd = bpf_program__fd(dummy_prog);
	if (prog_fd < 0 || dummy_prog_fd < 0) {
		printf("bpf_prog_load_xattr: %s\n", strerror(errno));
		return 1;
	}

	tx_port_map_fd = bpf_object__find_map_fd_by_name(obj, "tx_port");
	rxcnt_map_fd = bpf_object__find_map_fd_by_name(obj, "rxcnt");
	if (tx_port_map_fd < 0 || rxcnt_map_fd < 0) {
		printf("bpf_object__find_map_fd_by_name failed\n");
		return 1;
	}

	if (bpf_set_link_xdp_fd(ifindex_in, prog_fd, xdp_flags) < 0) {
		printf("ERROR: link set xdp fd failed on %d\n", ifindex_in);
		return 1;
	}

	ret = bpf_obj_get_info_by_fd(prog_fd, &info, &info_len);
	if (ret) {
		printf("can't get prog info - %s\n", strerror(errno));
		return ret;
	}
	prog_id = info.id;

	/* Loading dummy XDP prog on out-device */
	if (bpf_set_link_xdp_fd(ifindex_out, dummy_prog_fd,
			    (xdp_flags | XDP_FLAGS_UPDATE_IF_NOEXIST)) < 0) {
		printf("WARN: link set xdp fd failed on %d\n", ifindex_out);
		ifindex_out_xdp_dummy_attached = false;
	}

	memset(&info, 0, sizeof(info));
	ret = bpf_obj_get_info_by_fd(dummy_prog_fd, &info, &info_len);
	if (ret) {
		printf("can't get prog info - %s\n", strerror(errno));
		return ret;
	}
	dummy_prog_id = info.id;

	signal(SIGINT, int_exit);
	signal(SIGTERM, int_exit);

	/* bpf redirect port */
	ret = bpf_map_update_elem(tx_port_map_fd, &key, &ifindex_out, 0);
	if (ret) {
		perror("bpf_update_elem");
		goto out;
	}

	poll_stats(2, ifindex_out);

out:
	return 0;
}
Commit	Line	Data
5b497af4	1	// SPDX-License-Identifier: GPL-2.0-only
832622e6	2	/* Copyright (c) 2016 John Fastabend <john.r.fastabend@intel.com>
832622e6 JF	3	*/
832622e6 JF	4	#include <linux/bpf.h>
24251c26	5	#include <linux/if_link.h>
832622e6 JF	6	#include <assert.h>
	7	#include <errno.h>
	8	#include <signal.h>
	9	#include <stdio.h>
	10	#include <stdlib.h>
306da4e6	11	#include <stdbool.h>
832622e6	12	#include <string.h>
9e859e8f	13	#include <net/if.h>
832622e6	14	#include <unistd.h>
24251c26	15	#include <libgen.h>
8ac2441e	16	#include <sys/resource.h>
832622e6	17
832622e6	18	#include "bpf_util.h"
2bf3e2ef	19	#include <bpf/bpf.h>
7cf245a3	20	#include <bpf/libbpf.h>
832622e6 JF	21
	22	static int ifindex_in;
	23	static int ifindex_out;
306da4e6	24	static bool ifindex_out_xdp_dummy_attached = true;
3b7a8ec2 MF	25	static __u32 prog_id;
3b7a8ec2 MF	26	static __u32 dummy_prog_id;
832622e6	27
743e568c	28	static __u32 xdp_flags = XDP_FLAGS_UPDATE_IF_NOEXIST;
bbaf6029	29	static int rxcnt_map_fd;
24251c26	30
832622e6 JF	31	static void int_exit(int sig)
832622e6 JF	32	{
3b7a8ec2 MF	33	__u32 curr_prog_id = 0;
	34
	35	if (bpf_get_link_xdp_id(ifindex_in, &curr_prog_id, xdp_flags)) {
	36	printf("bpf_get_link_xdp_id failed\n");
	37	exit(1);
	38	}
	39	if (prog_id == curr_prog_id)
	40	bpf_set_link_xdp_fd(ifindex_in, -1, xdp_flags);
	41	else if (!curr_prog_id)
	42	printf("couldn't find a prog id on iface IN\n");
	43	else
	44	printf("program on iface IN changed, not removing\n");
	45
	46	if (ifindex_out_xdp_dummy_attached) {
	47	curr_prog_id = 0;
	48	if (bpf_get_link_xdp_id(ifindex_out, &curr_prog_id,
	49	xdp_flags)) {
	50	printf("bpf_get_link_xdp_id failed\n");
	51	exit(1);
	52	}
915654fd	53	if (dummy_prog_id == curr_prog_id)
3b7a8ec2 MF	54	bpf_set_link_xdp_fd(ifindex_out, -1, xdp_flags);
	55	else if (!curr_prog_id)
	56	printf("couldn't find a prog id on iface OUT\n");
	57	else
	58	printf("program on iface OUT changed, not removing\n");
	59	}
832622e6 JF	60	exit(0);
	61	}
	62
832622e6 JF	63	static void poll_stats(int interval, int ifindex)
	64	{
	65	unsigned int nr_cpus = bpf_num_possible_cpus();
	66	__u64 values[nr_cpus], prev[nr_cpus];
	67
	68	memset(prev, 0, sizeof(prev));
	69
	70	while (1) {
	71	__u64 sum = 0;
	72	__u32 key = 0;
	73	int i;
	74
	75	sleep(interval);
bbaf6029	76	assert(bpf_map_lookup_elem(rxcnt_map_fd, &key, values) == 0);
832622e6 JF	77	for (i = 0; i < nr_cpus; i++)
	78	sum += (values[i] - prev[i]);
	79	if (sum)
	80	printf("ifindex %i: %10llu pkt/s\n",
	81	ifindex, sum / interval);
	82	memcpy(prev, values, sizeof(values));
	83	}
	84	}
	85
24251c26	86	static void usage(const char *prog)
832622e6	87	{
24251c26	88	fprintf(stderr,
9e859e8f	89	"usage: %s [OPTS] <IFNAME\|IFINDEX>_IN <IFNAME\|IFINDEX>_OUT\n\n"
24251c26 AG	90	"OPTS:\n"
24251c26 AG	91	" -S use skb-mode\n"
743e568c MF	92	" -N enforce native mode\n"
743e568c MF	93	" -F force loading prog\n",
24251c26 AG	94	prog);
24251c26 AG	95	}
832622e6	96
832622e6	97
24251c26 AG	98	int main(int argc, char **argv)
24251c26 AG	99	{
bbaf6029 MF	100	struct bpf_prog_load_attr prog_load_attr = {
	101	.prog_type = BPF_PROG_TYPE_XDP,
	102	};
	103	struct bpf_program prog, dummy_prog;
	104	int prog_fd, tx_port_map_fd, opt;
3b7a8ec2 MF	105	struct bpf_prog_info info = {};
3b7a8ec2 MF	106	__u32 info_len = sizeof(info);
743e568c	107	const char *optstr = "FSN";
bbaf6029	108	struct bpf_object *obj;
24251c26	109	char filename[256];
bbaf6029 MF	110	int dummy_prog_fd;
bbaf6029 MF	111	int ret, key = 0;
24251c26 AG	112
	113	while ((opt = getopt(argc, argv, optstr)) != -1) {
	114	switch (opt) {
	115	case 'S':
	116	xdp_flags \|= XDP_FLAGS_SKB_MODE;
	117	break;
	118	case 'N':
d50ecc46	119	/* default, set below */
24251c26	120	break;
743e568c MF	121	case 'F':
	122	xdp_flags &= ~XDP_FLAGS_UPDATE_IF_NOEXIST;
	123	break;
24251c26 AG	124	default:
	125	usage(basename(argv[0]));
	126	return 1;
	127	}
	128	}
	129
d50ecc46 THJ	130	if (!(xdp_flags & XDP_FLAGS_SKB_MODE))
	131	xdp_flags \|= XDP_FLAGS_DRV_MODE;
	132
24251c26	133	if (optind == argc) {
9e859e8f	134	printf("usage: %s <IFNAME\|IFINDEX>_IN <IFNAME\|IFINDEX>_OUT\n", argv[0]);
832622e6 JF	135	return 1;
	136	}
	137
9e859e8f DL	138	ifindex_in = if_nametoindex(argv[optind]);
	139	if (!ifindex_in)
	140	ifindex_in = strtoul(argv[optind], NULL, 0);
	141
	142	ifindex_out = if_nametoindex(argv[optind + 1]);
	143	if (!ifindex_out)
	144	ifindex_out = strtoul(argv[optind + 1], NULL, 0);
	145
24251c26 AG	146	printf("input: %d output: %d\n", ifindex_in, ifindex_out);
	147
	148	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
bbaf6029	149	prog_load_attr.file = filename;
832622e6	150
bbaf6029 MF	151	if (bpf_prog_load_xattr(&prog_load_attr, &obj, &prog_fd))
	152	return 1;
	153
	154	prog = bpf_program__next(NULL, obj);
	155	dummy_prog = bpf_program__next(prog, obj);
	156	if (!prog \|\| !dummy_prog) {
	157	printf("finding a prog in obj file failed\n");
	158	return 1;
	159	}
	160	/* bpf_prog_load_xattr gives us the pointer to first prog's fd,
	161	* so we're missing only the fd for dummy prog
	162	*/
	163	dummy_prog_fd = bpf_program__fd(dummy_prog);
	164	if (prog_fd < 0 \|\| dummy_prog_fd < 0) {
	165	printf("bpf_prog_load_xattr: %s\n", strerror(errno));
832622e6 JF	166	return 1;
	167	}
	168
bbaf6029 MF	169	tx_port_map_fd = bpf_object__find_map_fd_by_name(obj, "tx_port");
	170	rxcnt_map_fd = bpf_object__find_map_fd_by_name(obj, "rxcnt");
	171	if (tx_port_map_fd < 0 \|\| rxcnt_map_fd < 0) {
	172	printf("bpf_object__find_map_fd_by_name failed\n");
832622e6 JF	173	return 1;
	174	}
	175
bbaf6029	176	if (bpf_set_link_xdp_fd(ifindex_in, prog_fd, xdp_flags) < 0) {
306da4e6	177	printf("ERROR: link set xdp fd failed on %d\n", ifindex_in);
832622e6 JF	178	return 1;
	179	}
	180
3b7a8ec2 MF	181	ret = bpf_obj_get_info_by_fd(prog_fd, &info, &info_len);
	182	if (ret) {
	183	printf("can't get prog info - %s\n", strerror(errno));
	184	return ret;
	185	}
	186	prog_id = info.id;
	187
306da4e6	188	/* Loading dummy XDP prog on out-device */
bbaf6029	189	if (bpf_set_link_xdp_fd(ifindex_out, dummy_prog_fd,
306da4e6 JDB	190	(xdp_flags \| XDP_FLAGS_UPDATE_IF_NOEXIST)) < 0) {
	191	printf("WARN: link set xdp fd failed on %d\n", ifindex_out);
	192	ifindex_out_xdp_dummy_attached = false;
	193	}
	194
3b7a8ec2	195	memset(&info, 0, sizeof(info));
20f6239d	196	ret = bpf_obj_get_info_by_fd(dummy_prog_fd, &info, &info_len);
3b7a8ec2 MF	197	if (ret) {
	198	printf("can't get prog info - %s\n", strerror(errno));
	199	return ret;
	200	}
	201	dummy_prog_id = info.id;
	202
306da4e6 JDB	203	signal(SIGINT, int_exit);
	204	signal(SIGTERM, int_exit);
	205
832622e6	206	/* bpf redirect port */
bbaf6029	207	ret = bpf_map_update_elem(tx_port_map_fd, &key, &ifindex_out, 0);
832622e6 JF	208	if (ret) {
	209	perror("bpf_update_elem");
	210	goto out;
	211	}
	212
	213	poll_stats(2, ifindex_out);
	214
	215	out:
	216	return 0;
	217	}