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![Linkui Xiao](/assets/img/avatar_default.png)
The ARRAY_SIZE macro is more compact and more formal in linux source. Signed-off-by: Linkui Xiao <xiaolinkui@kylinos.cn> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/bpf/20220712072302.13761-1-xiaolinkui@kylinos.cn
195 lines
4.3 KiB
C
195 lines
4.3 KiB
C
#include <linux/unistd.h>
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#include <linux/bpf.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <stdint.h>
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#include <unistd.h>
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#include <string.h>
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#include <assert.h>
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#include <errno.h>
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#include <sys/types.h>
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#include <sys/socket.h>
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#include <bpf/bpf.h>
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#include <bpf/libbpf.h>
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#include "bpf_insn.h"
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#include "sock_example.h"
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#include "bpf_util.h"
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#define BPF_F_PIN (1 << 0)
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#define BPF_F_GET (1 << 1)
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#define BPF_F_PIN_GET (BPF_F_PIN | BPF_F_GET)
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#define BPF_F_KEY (1 << 2)
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#define BPF_F_VAL (1 << 3)
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#define BPF_F_KEY_VAL (BPF_F_KEY | BPF_F_VAL)
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#define BPF_M_UNSPEC 0
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#define BPF_M_MAP 1
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#define BPF_M_PROG 2
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char bpf_log_buf[BPF_LOG_BUF_SIZE];
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static void usage(void)
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{
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printf("Usage: fds_example [...]\n");
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printf(" -F <file> File to pin/get object\n");
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printf(" -P |- pin object\n");
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printf(" -G `- get object\n");
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printf(" -m eBPF map mode\n");
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printf(" -k <key> |- map key\n");
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printf(" -v <value> `- map value\n");
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printf(" -p eBPF prog mode\n");
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printf(" -o <object> `- object file\n");
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printf(" -h Display this help.\n");
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}
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static int bpf_prog_create(const char *object)
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{
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static struct bpf_insn insns[] = {
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BPF_MOV64_IMM(BPF_REG_0, 1),
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BPF_EXIT_INSN(),
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};
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size_t insns_cnt = ARRAY_SIZE(insns);
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struct bpf_object *obj;
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int err;
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if (object) {
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obj = bpf_object__open_file(object, NULL);
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assert(!libbpf_get_error(obj));
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err = bpf_object__load(obj);
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assert(!err);
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return bpf_program__fd(bpf_object__next_program(obj, NULL));
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} else {
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LIBBPF_OPTS(bpf_prog_load_opts, opts,
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.log_buf = bpf_log_buf,
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.log_size = BPF_LOG_BUF_SIZE,
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);
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return bpf_prog_load(BPF_PROG_TYPE_SOCKET_FILTER, NULL, "GPL",
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insns, insns_cnt, &opts);
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}
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}
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static int bpf_do_map(const char *file, uint32_t flags, uint32_t key,
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uint32_t value)
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{
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int fd, ret;
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if (flags & BPF_F_PIN) {
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fd = bpf_map_create(BPF_MAP_TYPE_ARRAY, NULL, sizeof(uint32_t),
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sizeof(uint32_t), 1024, NULL);
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printf("bpf: map fd:%d (%s)\n", fd, strerror(errno));
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assert(fd > 0);
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ret = bpf_obj_pin(fd, file);
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printf("bpf: pin ret:(%d,%s)\n", ret, strerror(errno));
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assert(ret == 0);
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} else {
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fd = bpf_obj_get(file);
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printf("bpf: get fd:%d (%s)\n", fd, strerror(errno));
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assert(fd > 0);
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}
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if ((flags & BPF_F_KEY_VAL) == BPF_F_KEY_VAL) {
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ret = bpf_map_update_elem(fd, &key, &value, 0);
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printf("bpf: fd:%d u->(%u:%u) ret:(%d,%s)\n", fd, key, value,
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ret, strerror(errno));
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assert(ret == 0);
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} else if (flags & BPF_F_KEY) {
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ret = bpf_map_lookup_elem(fd, &key, &value);
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printf("bpf: fd:%d l->(%u):%u ret:(%d,%s)\n", fd, key, value,
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ret, strerror(errno));
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assert(ret == 0);
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}
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return 0;
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}
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static int bpf_do_prog(const char *file, uint32_t flags, const char *object)
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{
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int fd, sock, ret;
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if (flags & BPF_F_PIN) {
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fd = bpf_prog_create(object);
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printf("bpf: prog fd:%d (%s)\n", fd, strerror(errno));
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assert(fd > 0);
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ret = bpf_obj_pin(fd, file);
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printf("bpf: pin ret:(%d,%s)\n", ret, strerror(errno));
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assert(ret == 0);
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} else {
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fd = bpf_obj_get(file);
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printf("bpf: get fd:%d (%s)\n", fd, strerror(errno));
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assert(fd > 0);
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}
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sock = open_raw_sock("lo");
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assert(sock > 0);
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ret = setsockopt(sock, SOL_SOCKET, SO_ATTACH_BPF, &fd, sizeof(fd));
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printf("bpf: sock:%d <- fd:%d attached ret:(%d,%s)\n", sock, fd,
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ret, strerror(errno));
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assert(ret == 0);
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return 0;
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}
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int main(int argc, char **argv)
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{
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const char *file = NULL, *object = NULL;
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uint32_t key = 0, value = 0, flags = 0;
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int opt, mode = BPF_M_UNSPEC;
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while ((opt = getopt(argc, argv, "F:PGmk:v:po:")) != -1) {
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switch (opt) {
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/* General args */
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case 'F':
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file = optarg;
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break;
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case 'P':
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flags |= BPF_F_PIN;
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break;
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case 'G':
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flags |= BPF_F_GET;
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break;
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/* Map-related args */
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case 'm':
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mode = BPF_M_MAP;
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break;
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case 'k':
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key = strtoul(optarg, NULL, 0);
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flags |= BPF_F_KEY;
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break;
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case 'v':
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value = strtoul(optarg, NULL, 0);
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flags |= BPF_F_VAL;
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break;
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/* Prog-related args */
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case 'p':
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mode = BPF_M_PROG;
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break;
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case 'o':
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object = optarg;
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break;
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default:
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goto out;
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}
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}
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if (!(flags & BPF_F_PIN_GET) || !file)
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goto out;
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switch (mode) {
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case BPF_M_MAP:
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return bpf_do_map(file, flags, key, value);
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case BPF_M_PROG:
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return bpf_do_prog(file, flags, object);
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}
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out:
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usage();
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return -1;
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}
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