1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Copyright (c) 2016 John Fastabend <john.r.fastabend@intel.com>
3  */
4 static 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 
28 static int mask = SAMPLE_RX_CNT | SAMPLE_REDIRECT_ERR_CNT |
29 		  SAMPLE_EXCEPTION_CNT | SAMPLE_DEVMAP_XMIT_CNT_MULTI;
30 
31 DEFINE_SAMPLE_INIT(xdp_redirect);
32 
33 static 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 
main(int argc,char ** argv)43 int 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 	/* Loading dummy XDP prog on out-device */
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;
169 end_destroy:
170 	xdp_redirect__destroy(skel);
171 end:
172 	sample_exit(ret);
173 }
174