[linux-block.git] / samples / bpf / fds_example.c

#include <linux/unistd.h>
#include <linux/bpf.h>

#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <unistd.h>
#include <string.h>
#include <assert.h>
#include <errno.h>

#include <sys/types.h>
#include <sys/socket.h>

#include <bpf/bpf.h>

#include <bpf/libbpf.h>
#include "bpf_insn.h"
#include "sock_example.h"

#define BPF_F_PIN	(1 << 0)
#define BPF_F_GET	(1 << 1)
#define BPF_F_PIN_GET	(BPF_F_PIN | BPF_F_GET)

#define BPF_F_KEY	(1 << 2)
#define BPF_F_VAL	(1 << 3)
#define BPF_F_KEY_VAL	(BPF_F_KEY | BPF_F_VAL)

#define BPF_M_UNSPEC	0
#define BPF_M_MAP	1
#define BPF_M_PROG	2

char bpf_log_buf[BPF_LOG_BUF_SIZE];

static void usage(void)
{
	printf("Usage: fds_example [...]\n");
	printf("       -F <file>   File to pin/get object\n");
	printf("       -P          |- pin object\n");
	printf("       -G          `- get object\n");
	printf("       -m          eBPF map mode\n");
	printf("       -k <key>    |- map key\n");
	printf("       -v <value>  `- map value\n");
	printf("       -p          eBPF prog mode\n");
	printf("       -o <object> `- object file\n");
	printf("       -h          Display this help.\n");
}

static int bpf_prog_create(const char *object)
{
	static struct bpf_insn insns[] = {
		BPF_MOV64_IMM(BPF_REG_0, 1),
		BPF_EXIT_INSN(),
	};
	size_t insns_cnt = sizeof(insns) / sizeof(struct bpf_insn);
	struct bpf_object *obj;
	int err;

	if (object) {
		obj = bpf_object__open_file(object, NULL);
		assert(!libbpf_get_error(obj));
		err = bpf_object__load(obj);
		assert(!err);
		return bpf_program__fd(bpf_object__next_program(obj, NULL));
	} else {
		LIBBPF_OPTS(bpf_prog_load_opts, opts,
			.log_buf = bpf_log_buf,
			.log_size = BPF_LOG_BUF_SIZE,
		);

		return bpf_prog_load(BPF_PROG_TYPE_SOCKET_FILTER, NULL, "GPL",
				     insns, insns_cnt, &opts);
	}
}

static int bpf_do_map(const char *file, uint32_t flags, uint32_t key,
		      uint32_t value)
{
	int fd, ret;

	if (flags & BPF_F_PIN) {
		fd = bpf_map_create(BPF_MAP_TYPE_ARRAY, NULL, sizeof(uint32_t),
				    sizeof(uint32_t), 1024, NULL);
		printf("bpf: map fd:%d (%s)\n", fd, strerror(errno));
		assert(fd > 0);

		ret = bpf_obj_pin(fd, file);
		printf("bpf: pin ret:(%d,%s)\n", ret, strerror(errno));
		assert(ret == 0);
	} else {
		fd = bpf_obj_get(file);
		printf("bpf: get fd:%d (%s)\n", fd, strerror(errno));
		assert(fd > 0);
	}

	if ((flags & BPF_F_KEY_VAL) == BPF_F_KEY_VAL) {
		ret = bpf_map_update_elem(fd, &key, &value, 0);
		printf("bpf: fd:%d u->(%u:%u) ret:(%d,%s)\n", fd, key, value,
		       ret, strerror(errno));
		assert(ret == 0);
	} else if (flags & BPF_F_KEY) {
		ret = bpf_map_lookup_elem(fd, &key, &value);
		printf("bpf: fd:%d l->(%u):%u ret:(%d,%s)\n", fd, key, value,
		       ret, strerror(errno));
		assert(ret == 0);
	}

	return 0;
}

static int bpf_do_prog(const char *file, uint32_t flags, const char *object)
{
	int fd, sock, ret;

	if (flags & BPF_F_PIN) {
		fd = bpf_prog_create(object);
		printf("bpf: prog fd:%d (%s)\n", fd, strerror(errno));
		assert(fd > 0);

		ret = bpf_obj_pin(fd, file);
		printf("bpf: pin ret:(%d,%s)\n", ret, strerror(errno));
		assert(ret == 0);
	} else {
		fd = bpf_obj_get(file);
		printf("bpf: get fd:%d (%s)\n", fd, strerror(errno));
		assert(fd > 0);
	}

	sock = open_raw_sock("lo");
	assert(sock > 0);

	ret = setsockopt(sock, SOL_SOCKET, SO_ATTACH_BPF, &fd, sizeof(fd));
	printf("bpf: sock:%d <- fd:%d attached ret:(%d,%s)\n", sock, fd,
	       ret, strerror(errno));
	assert(ret == 0);

	return 0;
}

int main(int argc, char **argv)
{
	const char *file = NULL, *object = NULL;
	uint32_t key = 0, value = 0, flags = 0;
	int opt, mode = BPF_M_UNSPEC;

	while ((opt = getopt(argc, argv, "F:PGmk:v:po:")) != -1) {
		switch (opt) {
		/* General args */
		case 'F':
			file = optarg;
			break;
		case 'P':
			flags |= BPF_F_PIN;
			break;
		case 'G':
			flags |= BPF_F_GET;
			break;
		/* Map-related args */
		case 'm':
			mode = BPF_M_MAP;
			break;
		case 'k':
			key = strtoul(optarg, NULL, 0);
			flags |= BPF_F_KEY;
			break;
		case 'v':
			value = strtoul(optarg, NULL, 0);
			flags |= BPF_F_VAL;
			break;
		/* Prog-related args */
		case 'p':
			mode = BPF_M_PROG;
			break;
		case 'o':
			object = optarg;
			break;
		default:
			goto out;
		}
	}

	if (!(flags & BPF_F_PIN_GET) || !file)
		goto out;

	switch (mode) {
	case BPF_M_MAP:
		return bpf_do_map(file, flags, key, value);
	case BPF_M_PROG:
		return bpf_do_prog(file, flags, object);
	}
out:
	usage();
	return -1;
}
Commit	Line	Data
42984d7c DB	1	#include <linux/unistd.h>
	2	#include <linux/bpf.h>
	3
	4	#include <stdio.h>
	5	#include <stdlib.h>
	6	#include <stdint.h>
	7	#include <unistd.h>
	8	#include <string.h>
	9	#include <assert.h>
	10	#include <errno.h>
	11
	12	#include <sys/types.h>
	13	#include <sys/socket.h>
	14
8d930450 JK	15	#include <bpf/bpf.h>
8d930450 JK	16
7cf245a3	17	#include <bpf/libbpf.h>
8d930450	18	#include "bpf_insn.h"
9899694a	19	#include "sock_example.h"
42984d7c DB	20
	21	#define BPF_F_PIN (1 << 0)
	22	#define BPF_F_GET (1 << 1)
	23	#define BPF_F_PIN_GET (BPF_F_PIN \| BPF_F_GET)
	24
	25	#define BPF_F_KEY (1 << 2)
	26	#define BPF_F_VAL (1 << 3)
	27	#define BPF_F_KEY_VAL (BPF_F_KEY \| BPF_F_VAL)
	28
	29	#define BPF_M_UNSPEC 0
	30	#define BPF_M_MAP 1
	31	#define BPF_M_PROG 2
	32
eef8a42d WZ	33	char bpf_log_buf[BPF_LOG_BUF_SIZE];
eef8a42d WZ	34
42984d7c DB	35	static void usage(void)
	36	{
	37	printf("Usage: fds_example [...]\n");
	38	printf(" -F <file> File to pin/get object\n");
	39	printf(" -P \|- pin object\n");
	40	printf(" -G `- get object\n");
	41	printf(" -m eBPF map mode\n");
	42	printf(" -k <key> \|- map key\n");
	43	printf(" -v <value> `- map value\n");
	44	printf(" -p eBPF prog mode\n");
	45	printf(" -o <object> `- object file\n");
	46	printf(" -h Display this help.\n");
	47	}
	48
42984d7c DB	49	static int bpf_prog_create(const char *object)
42984d7c DB	50	{
811b4f0d	51	static struct bpf_insn insns[] = {
42984d7c DB	52	BPF_MOV64_IMM(BPF_REG_0, 1),
	53	BPF_EXIT_INSN(),
	54	};
43371c83	55	size_t insns_cnt = sizeof(insns) / sizeof(struct bpf_insn);
1a9b268c	56	struct bpf_object *obj;
c58f9815	57	int err;
42984d7c DB	58
42984d7c DB	59	if (object) {
c58f9815 AN	60	obj = bpf_object__open_file(object, NULL);
	61	assert(!libbpf_get_error(obj));
	62	err = bpf_object__load(obj);
	63	assert(!err);
	64	return bpf_program__fd(bpf_object__next_program(obj, NULL));
42984d7c	65	} else {
c58f9815 AN	66	LIBBPF_OPTS(bpf_prog_load_opts, opts,
	67	.log_buf = bpf_log_buf,
	68	.log_size = BPF_LOG_BUF_SIZE,
	69	);
	70
	71	return bpf_prog_load(BPF_PROG_TYPE_SOCKET_FILTER, NULL, "GPL",
	72	insns, insns_cnt, &opts);
42984d7c DB	73	}
	74	}
	75
	76	static int bpf_do_map(const char *file, uint32_t flags, uint32_t key,
	77	uint32_t value)
	78	{
	79	int fd, ret;
	80
	81	if (flags & BPF_F_PIN) {
c58f9815 AN	82	fd = bpf_map_create(BPF_MAP_TYPE_ARRAY, NULL, sizeof(uint32_t),
c58f9815 AN	83	sizeof(uint32_t), 1024, NULL);
42984d7c DB	84	printf("bpf: map fd:%d (%s)\n", fd, strerror(errno));
	85	assert(fd > 0);
	86
	87	ret = bpf_obj_pin(fd, file);
	88	printf("bpf: pin ret:(%d,%s)\n", ret, strerror(errno));
	89	assert(ret == 0);
	90	} else {
	91	fd = bpf_obj_get(file);
	92	printf("bpf: get fd:%d (%s)\n", fd, strerror(errno));
	93	assert(fd > 0);
	94	}
	95
	96	if ((flags & BPF_F_KEY_VAL) == BPF_F_KEY_VAL) {
d40fc181	97	ret = bpf_map_update_elem(fd, &key, &value, 0);
42984d7c DB	98	printf("bpf: fd:%d u->(%u:%u) ret:(%d,%s)\n", fd, key, value,
	99	ret, strerror(errno));
	100	assert(ret == 0);
	101	} else if (flags & BPF_F_KEY) {
d40fc181	102	ret = bpf_map_lookup_elem(fd, &key, &value);
42984d7c DB	103	printf("bpf: fd:%d l->(%u):%u ret:(%d,%s)\n", fd, key, value,
	104	ret, strerror(errno));
	105	assert(ret == 0);
	106	}
	107
	108	return 0;
	109	}
	110
	111	static int bpf_do_prog(const char file, uint32_t flags, const char object)
	112	{
	113	int fd, sock, ret;
	114
	115	if (flags & BPF_F_PIN) {
	116	fd = bpf_prog_create(object);
	117	printf("bpf: prog fd:%d (%s)\n", fd, strerror(errno));
	118	assert(fd > 0);
	119
	120	ret = bpf_obj_pin(fd, file);
	121	printf("bpf: pin ret:(%d,%s)\n", ret, strerror(errno));
	122	assert(ret == 0);
	123	} else {
	124	fd = bpf_obj_get(file);
	125	printf("bpf: get fd:%d (%s)\n", fd, strerror(errno));
	126	assert(fd > 0);
	127	}
	128
	129	sock = open_raw_sock("lo");
	130	assert(sock > 0);
	131
	132	ret = setsockopt(sock, SOL_SOCKET, SO_ATTACH_BPF, &fd, sizeof(fd));
	133	printf("bpf: sock:%d <- fd:%d attached ret:(%d,%s)\n", sock, fd,
	134	ret, strerror(errno));
	135	assert(ret == 0);
	136
	137	return 0;
	138	}
	139
	140	int main(int argc, char **argv)
	141	{
	142	const char file = NULL, object = NULL;
	143	uint32_t key = 0, value = 0, flags = 0;
	144	int opt, mode = BPF_M_UNSPEC;
	145
	146	while ((opt = getopt(argc, argv, "F:PGmk:v:po:")) != -1) {
	147	switch (opt) {
	148	/* General args */
	149	case 'F':
	150	file = optarg;
	151	break;
	152	case 'P':
	153	flags \|= BPF_F_PIN;
	154	break;
	155	case 'G':
	156	flags \|= BPF_F_GET;
	157	break;
	158	/* Map-related args */
	159	case 'm':
	160	mode = BPF_M_MAP;
	161	break;
	162	case 'k':
	163	key = strtoul(optarg, NULL, 0);
	164	flags \|= BPF_F_KEY;
	165	break;
	166	case 'v':
167	value = strtoul(optarg, NULL, 0);
168	flags \|= BPF_F_VAL;
169	break;
170	/* Prog-related args */
171	case 'p':
172	mode = BPF_M_PROG;
173	break;
174	case 'o':
175	object = optarg;
176	break;
177	default:
178	goto out;
179	}
180	}
181
182	if (!(flags & BPF_F_PIN_GET) \|\| !file)
183	goto out;
184
185	switch (mode) {
186	case BPF_M_MAP:
187	return bpf_do_map(file, flags, key, value);
188	case BPF_M_PROG:
189	return bpf_do_prog(file, flags, object);
190	}
191	out:
192	usage();
193	return -1;
194	}