1/* Copyright (c) 2016 PLUMgrid
  2 *
  3 * This program is free software; you can redistribute it and/or
  4 * modify it under the terms of version 2 of the GNU General Public
  5 * License as published by the Free Software Foundation.
  6 */
  7#include <linux/bpf.h>
  8#include <linux/if_link.h>
  9#include <assert.h>
 10#include <errno.h>
 11#include <signal.h>
 12#include <stdio.h>
 13#include <stdlib.h>
 14#include <string.h>
 15#include <unistd.h>
 16#include <libgen.h>
 17#include <sys/resource.h>
 18
 19#include "bpf_load.h"
 20#include "bpf_util.h"
 21#include "libbpf.h"
 22
 23static int ifindex;
 24static __u32 xdp_flags;
 25
 26static void int_exit(int sig)
 27{
 28	bpf_set_link_xdp_fd(ifindex, -1, xdp_flags);
 29	exit(0);
 30}
 31
 32/* simple per-protocol drop counter
 33 */
 34static void poll_stats(int interval)
 35{
 36	unsigned int nr_cpus = bpf_num_possible_cpus();
 37	const unsigned int nr_keys = 256;
 38	__u64 values[nr_cpus], prev[nr_keys][nr_cpus];
 39	__u32 key;
 40	int i;
 41
 42	memset(prev, 0, sizeof(prev));
 43
 44	while (1) {
 45		sleep(interval);
 46
 47		for (key = 0; key < nr_keys; key++) {
 48			__u64 sum = 0;
 49
 50			assert(bpf_map_lookup_elem(map_fd[0], &key, values) == 0);
 51			for (i = 0; i < nr_cpus; i++)
 52				sum += (values[i] - prev[key][i]);
 53			if (sum)
 54				printf("proto %u: %10llu pkt/s\n",
 55				       key, sum / interval);
 56			memcpy(prev[key], values, sizeof(values));
 57		}
 58	}
 59}
 60
 61static void usage(const char *prog)
 62{
 63	fprintf(stderr,
 64		"usage: %s [OPTS] IFINDEX\n\n"
 65		"OPTS:\n"
 66		"    -S    use skb-mode\n"
 67		"    -N    enforce native mode\n",
 68		prog);
 69}
 70
 71int main(int argc, char **argv)
 72{
 73	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
 74	const char *optstr = "SN";
 75	char filename[256];
 76	int opt;
 77
 78	while ((opt = getopt(argc, argv, optstr)) != -1) {
 79		switch (opt) {
 80		case 'S':
 81			xdp_flags |= XDP_FLAGS_SKB_MODE;
 82			break;
 83		case 'N':
 84			xdp_flags |= XDP_FLAGS_DRV_MODE;
 85			break;
 86		default:
 87			usage(basename(argv[0]));
 88			return 1;
 89		}
 90	}
 91
 92	if (optind == argc) {
 93		usage(basename(argv[0]));
 94		return 1;
 95	}
 96
 97	if (setrlimit(RLIMIT_MEMLOCK, &r)) {
 98		perror("setrlimit(RLIMIT_MEMLOCK)");
 99		return 1;
100	}
101
102	ifindex = strtoul(argv[optind], NULL, 0);
103
104	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
105
106	if (load_bpf_file(filename)) {
107		printf("%s", bpf_log_buf);
108		return 1;
109	}
110
111	if (!prog_fd[0]) {
112		printf("load_bpf_file: %s\n", strerror(errno));
113		return 1;
114	}
115
116	signal(SIGINT, int_exit);
117	signal(SIGTERM, int_exit);
118
119	if (bpf_set_link_xdp_fd(ifindex, prog_fd[0], xdp_flags) < 0) {
120		printf("link set xdp fd failed\n");
121		return 1;
122	}
123
124	poll_stats(2);
125
126	return 0;
127}