// SPDX-License-Identifier: GPL-2.0-only /* Copyright (c) 2016 PLUMgrid */ #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 <string.h> #include <unistd.h> #include <libgen.h> #include <sys/resource.h> #include <net/if.h> #include "bpf_util.h" #include <bpf/bpf.h> #include <bpf/libbpf.h> static int ifindex; static __u32 xdp_flags = XDP_FLAGS_UPDATE_IF_NOEXIST; static __u32 prog_id; static void int_exit(int sig) { __u32 curr_prog_id = 0; if (bpf_get_link_xdp_id(ifindex, &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, -1, xdp_flags); else if (!curr_prog_id) printf("couldn't find a prog id on a given interface\n"); else printf("program on interface changed, not removing\n"); exit(0); } /* simple per-protocol drop counter */ static void poll_stats(int map_fd, int interval) { unsigned int nr_cpus = bpf_num_possible_cpus(); __u64 values[nr_cpus], prev[UINT8_MAX] = { 0 }; int i; while (1) { __u32 key = UINT32_MAX; sleep(interval); while (bpf_map_get_next_key(map_fd, &key, &key) != -1) { __u64 sum = 0; assert(bpf_map_lookup_elem(map_fd, &key, values) == 0); for (i = 0; i < nr_cpus; i++) sum += values[i]; if (sum > prev[key]) printf("proto %u: %10llu pkt/s\n", key, (sum - prev[key]) / interval); prev[key] = sum; } } } static void usage(const char *prog) { fprintf(stderr, "usage: %s [OPTS] IFACE\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 rlimit r = {RLIM_INFINITY, RLIM_INFINITY}; struct bpf_prog_load_attr prog_load_attr = { .prog_type = BPF_PROG_TYPE_XDP, }; struct bpf_prog_info info = {}; __u32 info_len = sizeof(info); const char *optstr = "FSN"; int prog_fd, map_fd, opt; struct bpf_object *obj; struct bpf_map *map; char filename[256]; int err; 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) { usage(basename(argv[0])); return 1; } if (setrlimit(RLIMIT_MEMLOCK, &r)) { perror("setrlimit(RLIMIT_MEMLOCK)"); return 1; } ifindex = if_nametoindex(argv[optind]); if (!ifindex) { perror("if_nametoindex"); return 1; } 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; map = bpf_map__next(NULL, obj); if (!map) { printf("finding a map in obj file failed\n"); return 1; } map_fd = bpf_map__fd(map); if (!prog_fd) { printf("bpf_prog_load_xattr: %s\n", strerror(errno)); return 1; } signal(SIGINT, int_exit); signal(SIGTERM, int_exit); if (bpf_set_link_xdp_fd(ifindex, prog_fd, xdp_flags) < 0) { printf("link set xdp fd failed\n"); return 1; } err = bpf_obj_get_info_by_fd(prog_fd, &info, &info_len); if (err) { printf("can't get prog info - %s\n", strerror(errno)); return err; } prog_id = info.id; poll_stats(map_fd, 2); return 0; }