1
2
3
4static const char *__doc__ =
5"XDP redirect tool, using bpf_redirect helper\n"
6"Usage: xdp_redirect <IFINDEX|IFNAME>_IN <IFINDEX|IFNAME>_OUT\n";
7
8#include <linux/bpf.h>
9#include <linux/if_link.h>
10#include <assert.h>
11#include <errno.h>
12#include <signal.h>
13#include <stdio.h>
14#include <stdlib.h>
15#include <stdbool.h>
16#include <string.h>
17#include <net/if.h>
18#include <unistd.h>
19#include <libgen.h>
20#include <getopt.h>
21#include <sys/resource.h>
22#include <bpf/bpf.h>
23#include <bpf/libbpf.h>
24#include "bpf_util.h"
25#include "xdp_sample_user.h"
26#include "xdp_redirect.skel.h"
27
28static int mask = SAMPLE_RX_CNT | SAMPLE_REDIRECT_ERR_CNT |
29 SAMPLE_EXCEPTION_CNT | SAMPLE_DEVMAP_XMIT_CNT_MULTI;
30
31DEFINE_SAMPLE_INIT(xdp_redirect);
32
33static const struct option long_options[] = {
34 {"help", no_argument, NULL, 'h' },
35 {"skb-mode", no_argument, NULL, 'S' },
36 {"force", no_argument, NULL, 'F' },
37 {"stats", no_argument, NULL, 's' },
38 {"interval", required_argument, NULL, 'i' },
39 {"verbose", no_argument, NULL, 'v' },
40 {}
41};
42
43int main(int argc, char **argv)
44{
45 int ifindex_in, ifindex_out, opt;
46 char str[2 * IF_NAMESIZE + 1];
47 char ifname_out[IF_NAMESIZE];
48 char ifname_in[IF_NAMESIZE];
49 int ret = EXIT_FAIL_OPTION;
50 unsigned long interval = 2;
51 struct xdp_redirect *skel;
52 bool generic = false;
53 bool force = false;
54 bool error = true;
55
56 while ((opt = getopt_long(argc, argv, "hSFi:vs",
57 long_options, NULL)) != -1) {
58 switch (opt) {
59 case 'S':
60 generic = true;
61 mask &= ~(SAMPLE_DEVMAP_XMIT_CNT |
62 SAMPLE_DEVMAP_XMIT_CNT_MULTI);
63 break;
64 case 'F':
65 force = true;
66 break;
67 case 'i':
68 interval = strtoul(optarg, NULL, 0);
69 break;
70 case 'v':
71 sample_switch_mode();
72 break;
73 case 's':
74 mask |= SAMPLE_REDIRECT_CNT;
75 break;
76 case 'h':
77 error = false;
78 default:
79 sample_usage(argv, long_options, __doc__, mask, error);
80 return ret;
81 }
82 }
83
84 if (argc <= optind + 1) {
85 sample_usage(argv, long_options, __doc__, mask, true);
86 return ret;
87 }
88
89 ifindex_in = if_nametoindex(argv[optind]);
90 if (!ifindex_in)
91 ifindex_in = strtoul(argv[optind], NULL, 0);
92
93 ifindex_out = if_nametoindex(argv[optind + 1]);
94 if (!ifindex_out)
95 ifindex_out = strtoul(argv[optind + 1], NULL, 0);
96
97 if (!ifindex_in || !ifindex_out) {
98 fprintf(stderr, "Bad interface index or name\n");
99 sample_usage(argv, long_options, __doc__, mask, true);
100 goto end;
101 }
102
103 skel = xdp_redirect__open();
104 if (!skel) {
105 fprintf(stderr, "Failed to xdp_redirect__open: %s\n", strerror(errno));
106 ret = EXIT_FAIL_BPF;
107 goto end;
108 }
109
110 ret = sample_init_pre_load(skel);
111 if (ret < 0) {
112 fprintf(stderr, "Failed to sample_init_pre_load: %s\n", strerror(-ret));
113 ret = EXIT_FAIL_BPF;
114 goto end_destroy;
115 }
116
117 skel->rodata->from_match[0] = ifindex_in;
118 skel->rodata->to_match[0] = ifindex_out;
119 skel->rodata->ifindex_out = ifindex_out;
120
121 ret = xdp_redirect__load(skel);
122 if (ret < 0) {
123 fprintf(stderr, "Failed to xdp_redirect__load: %s\n", strerror(errno));
124 ret = EXIT_FAIL_BPF;
125 goto end_destroy;
126 }
127
128 ret = sample_init(skel, mask);
129 if (ret < 0) {
130 fprintf(stderr, "Failed to initialize sample: %s\n", strerror(-ret));
131 ret = EXIT_FAIL;
132 goto end_destroy;
133 }
134
135 ret = EXIT_FAIL_XDP;
136 if (sample_install_xdp(skel->progs.xdp_redirect_prog, ifindex_in,
137 generic, force) < 0)
138 goto end_destroy;
139
140
141 sample_install_xdp(skel->progs.xdp_redirect_dummy_prog, ifindex_out,
142 generic, force);
143
144 ret = EXIT_FAIL;
145 if (!if_indextoname(ifindex_in, ifname_in)) {
146 fprintf(stderr, "Failed to if_indextoname for %d: %s\n", ifindex_in,
147 strerror(errno));
148 goto end_destroy;
149 }
150
151 if (!if_indextoname(ifindex_out, ifname_out)) {
152 fprintf(stderr, "Failed to if_indextoname for %d: %s\n", ifindex_out,
153 strerror(errno));
154 goto end_destroy;
155 }
156
157 safe_strncpy(str, get_driver_name(ifindex_in), sizeof(str));
158 printf("Redirecting from %s (ifindex %d; driver %s) to %s (ifindex %d; driver %s)\n",
159 ifname_in, ifindex_in, str, ifname_out, ifindex_out, get_driver_name(ifindex_out));
160 snprintf(str, sizeof(str), "%s->%s", ifname_in, ifname_out);
161
162 ret = sample_run(interval, NULL, NULL);
163 if (ret < 0) {
164 fprintf(stderr, "Failed during sample run: %s\n", strerror(-ret));
165 ret = EXIT_FAIL;
166 goto end_destroy;
167 }
168 ret = EXIT_OK;
169end_destroy:
170 xdp_redirect__destroy(skel);
171end:
172 sample_exit(ret);
173}
174
