| // 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 <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_xdp_query_id(ifindex, xdp_flags, &curr_prog_id)) { |
| printf("bpf_xdp_query_id failed\n"); |
| exit(1); |
| } |
| if (prog_id == curr_prog_id) |
| bpf_xdp_detach(ifindex, xdp_flags, NULL); |
| 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) == 0) { |
| __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 bpf_prog_info info = {}; |
| __u32 info_len = sizeof(info); |
| const char *optstr = "FSN"; |
| int prog_fd, map_fd, opt; |
| struct bpf_program *prog; |
| 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; |
| } |
| |
| ifindex = if_nametoindex(argv[optind]); |
| if (!ifindex) { |
| perror("if_nametoindex"); |
| return 1; |
| } |
| |
| snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]); |
| obj = bpf_object__open_file(filename, NULL); |
| if (libbpf_get_error(obj)) |
| return 1; |
| |
| prog = bpf_object__next_program(obj, NULL); |
| bpf_program__set_type(prog, BPF_PROG_TYPE_XDP); |
| |
| err = bpf_object__load(obj); |
| if (err) |
| return 1; |
| |
| prog_fd = bpf_program__fd(prog); |
| |
| map = bpf_object__next_map(obj, NULL); |
| 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_xdp_attach(ifindex, prog_fd, xdp_flags, NULL) < 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, 1); |
| |
| return 0; |
| } |