1 // SPDX-License-Identifier: GPL-2.0
5 #include <linux/perf_event.h>
10 #include <sys/sysinfo.h>
11 #include <sys/ioctl.h>
13 #include <bpf/libbpf.h>
15 #include <sys/resource.h>
17 #include <linux/if_link.h>
23 static __u32 xdp_flags = XDP_FLAGS_UPDATE_IF_NOEXIST;
25 static struct perf_buffer *pb = NULL;
27 static int do_attach(int idx, int fd, const char *name)
29 struct bpf_prog_info info = {};
30 __u32 info_len = sizeof(info);
33 err = bpf_set_link_xdp_fd(idx, fd, xdp_flags);
35 printf("ERROR: failed to attach program to %s\n", name);
39 err = bpf_obj_get_info_by_fd(fd, &info, &info_len);
41 printf("can't get prog info - %s\n", strerror(errno));
49 static int do_detach(int idx, const char *name)
51 __u32 curr_prog_id = 0;
54 err = bpf_get_link_xdp_id(idx, &curr_prog_id, xdp_flags);
56 printf("bpf_get_link_xdp_id failed\n");
59 if (prog_id == curr_prog_id) {
60 err = bpf_set_link_xdp_fd(idx, -1, xdp_flags);
62 printf("ERROR: failed to detach prog from %s\n", name);
63 } else if (!curr_prog_id) {
64 printf("couldn't find a prog id on a %s\n", name);
66 printf("program on interface changed, not removing\n");
72 #define SAMPLE_SIZE 64
74 static void print_bpf_output(void *ctx, int cpu, void *data, __u32 size)
79 __u8 pkt_data[SAMPLE_SIZE];
83 if (e->cookie != 0xdead) {
84 printf("BUG cookie %x sized %d\n", e->cookie, size);
88 printf("Pkt len: %-5d bytes. Ethernet hdr: ", e->pkt_len);
89 for (i = 0; i < 14 && i < e->pkt_len; i++)
90 printf("%02x ", e->pkt_data[i]);
94 static void sig_handler(int signo)
96 do_detach(if_idx, if_name);
97 perf_buffer__free(pb);
101 static void usage(const char *prog)
104 "%s: %s [OPTS] <ifname|ifindex>\n\n"
106 " -F force loading prog\n"
107 " -S use skb-mode\n",
111 int main(int argc, char **argv)
113 const char *optstr = "FS";
114 int prog_fd, map_fd, opt;
115 struct bpf_program *prog;
116 struct bpf_object *obj;
121 while ((opt = getopt(argc, argv, optstr)) != -1) {
124 xdp_flags &= ~XDP_FLAGS_UPDATE_IF_NOEXIST;
127 xdp_flags |= XDP_FLAGS_SKB_MODE;
130 usage(basename(argv[0]));
135 if (!(xdp_flags & XDP_FLAGS_SKB_MODE))
136 xdp_flags |= XDP_FLAGS_DRV_MODE;
138 if (optind == argc) {
139 usage(basename(argv[0]));
143 snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
145 obj = bpf_object__open_file(filename, NULL);
146 if (libbpf_get_error(obj))
149 prog = bpf_object__next_program(obj, NULL);
150 bpf_program__set_type(prog, BPF_PROG_TYPE_XDP);
152 err = bpf_object__load(obj);
156 prog_fd = bpf_program__fd(prog);
158 map = bpf_object__next_map(obj, NULL);
160 printf("finding a map in obj file failed\n");
163 map_fd = bpf_map__fd(map);
165 if_idx = if_nametoindex(argv[optind]);
167 if_idx = strtoul(argv[optind], NULL, 0);
170 fprintf(stderr, "Invalid ifname\n");
173 if_name = argv[optind];
174 err = do_attach(if_idx, prog_fd, if_name);
178 if (signal(SIGINT, sig_handler) ||
179 signal(SIGHUP, sig_handler) ||
180 signal(SIGTERM, sig_handler)) {
185 pb = perf_buffer__new(map_fd, 8, print_bpf_output, NULL, NULL, NULL);
186 err = libbpf_get_error(pb);
188 perror("perf_buffer setup failed");
192 while ((ret = perf_buffer__poll(pb, 1000)) >= 0) {