1 /* Copyright (c) 2016 John Fastabend <john.r.fastabend@intel.com>
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 * This program is distributed in the hope that it will be useful, but
8 * WITHOUT ANY WARRANTY; without even the implied warranty of
9 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
10 * General Public License for more details.
11 */
12 #include <linux/bpf.h>
13 #include <linux/if_link.h>
14 #include <assert.h>
15 #include <errno.h>
16 #include <signal.h>
17 #include <stdio.h>
18 #include <stdlib.h>
19 #include <stdbool.h>
20 #include <string.h>
21 #include <unistd.h>
22 #include <libgen.h>
23 #include <sys/resource.h>
24
25 #include "bpf_load.h"
26 #include "bpf_util.h"
27 #include <bpf/bpf.h>
28
29 static int ifindex_in;
30 static int ifindex_out;
31 static bool ifindex_out_xdp_dummy_attached = true;
32
33 static __u32 xdp_flags;
34
int_exit(int sig)35 static void int_exit(int sig)
36 {
37 bpf_set_link_xdp_fd(ifindex_in, -1, xdp_flags);
38 if (ifindex_out_xdp_dummy_attached)
39 bpf_set_link_xdp_fd(ifindex_out, -1, xdp_flags);
40 exit(0);
41 }
42
poll_stats(int interval,int ifindex)43 static void poll_stats(int interval, int ifindex)
44 {
45 unsigned int nr_cpus = bpf_num_possible_cpus();
46 __u64 values[nr_cpus], prev[nr_cpus];
47
48 memset(prev, 0, sizeof(prev));
49
50 while (1) {
51 __u64 sum = 0;
52 __u32 key = 0;
53 int i;
54
55 sleep(interval);
56 assert(bpf_map_lookup_elem(map_fd[1], &key, values) == 0);
57 for (i = 0; i < nr_cpus; i++)
58 sum += (values[i] - prev[i]);
59 if (sum)
60 printf("ifindex %i: %10llu pkt/s\n",
61 ifindex, sum / interval);
62 memcpy(prev, values, sizeof(values));
63 }
64 }
65
usage(const char * prog)66 static void usage(const char *prog)
67 {
68 fprintf(stderr,
69 "usage: %s [OPTS] IFINDEX_IN IFINDEX_OUT\n\n"
70 "OPTS:\n"
71 " -S use skb-mode\n"
72 " -N enforce native mode\n",
73 prog);
74 }
75
76
main(int argc,char ** argv)77 int main(int argc, char **argv)
78 {
79 struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
80 const char *optstr = "SN";
81 char filename[256];
82 int ret, opt, key = 0;
83
84 while ((opt = getopt(argc, argv, optstr)) != -1) {
85 switch (opt) {
86 case 'S':
87 xdp_flags |= XDP_FLAGS_SKB_MODE;
88 break;
89 case 'N':
90 xdp_flags |= XDP_FLAGS_DRV_MODE;
91 break;
92 default:
93 usage(basename(argv[0]));
94 return 1;
95 }
96 }
97
98 if (optind == argc) {
99 printf("usage: %s IFINDEX_IN IFINDEX_OUT\n", argv[0]);
100 return 1;
101 }
102
103 if (setrlimit(RLIMIT_MEMLOCK, &r)) {
104 perror("setrlimit(RLIMIT_MEMLOCK)");
105 return 1;
106 }
107
108 ifindex_in = strtoul(argv[optind], NULL, 0);
109 ifindex_out = strtoul(argv[optind + 1], NULL, 0);
110 printf("input: %d output: %d\n", ifindex_in, ifindex_out);
111
112 snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
113
114 if (load_bpf_file(filename)) {
115 printf("%s", bpf_log_buf);
116 return 1;
117 }
118
119 if (!prog_fd[0]) {
120 printf("load_bpf_file: %s\n", strerror(errno));
121 return 1;
122 }
123
124 if (bpf_set_link_xdp_fd(ifindex_in, prog_fd[0], xdp_flags) < 0) {
125 printf("ERROR: link set xdp fd failed on %d\n", ifindex_in);
126 return 1;
127 }
128
129 /* Loading dummy XDP prog on out-device */
130 if (bpf_set_link_xdp_fd(ifindex_out, prog_fd[1],
131 (xdp_flags | XDP_FLAGS_UPDATE_IF_NOEXIST)) < 0) {
132 printf("WARN: link set xdp fd failed on %d\n", ifindex_out);
133 ifindex_out_xdp_dummy_attached = false;
134 }
135
136 signal(SIGINT, int_exit);
137 signal(SIGTERM, int_exit);
138
139 /* bpf redirect port */
140 ret = bpf_map_update_elem(map_fd[0], &key, &ifindex_out, 0);
141 if (ret) {
142 perror("bpf_update_elem");
143 goto out;
144 }
145
146 poll_stats(2, ifindex_out);
147
148 out:
149 return 0;
150 }
151
