1
2#include <linux/bpf.h>
3#include <linux/if_link.h>
4#include <assert.h>
5#include <errno.h>
6#include <signal.h>
7#include <stdio.h>
8#include <stdlib.h>
9#include <string.h>
10#include <net/if.h>
11#include <unistd.h>
12#include <libgen.h>
13#include <sys/resource.h>
14#include <sys/ioctl.h>
15#include <sys/types.h>
16#include <sys/socket.h>
17#include <netinet/in.h>
18
19#include "bpf_util.h"
20#include <bpf/bpf.h>
21#include <bpf/libbpf.h>
22
23#define MAX_IFACE_NUM 32
24#define MAX_INDEX_NUM 1024
25
26static __u32 xdp_flags = XDP_FLAGS_UPDATE_IF_NOEXIST;
27static int ifaces[MAX_IFACE_NUM] = {};
28
29static void int_exit(int sig)
30{
31 __u32 prog_id = 0;
32 int i;
33
34 for (i = 0; ifaces[i] > 0; i++) {
35 if (bpf_get_link_xdp_id(ifaces[i], &prog_id, xdp_flags)) {
36 printf("bpf_get_link_xdp_id failed\n");
37 exit(1);
38 }
39 if (prog_id)
40 bpf_set_link_xdp_fd(ifaces[i], -1, xdp_flags);
41 }
42
43 exit(0);
44}
45
46static int get_mac_addr(unsigned int ifindex, void *mac_addr)
47{
48 char ifname[IF_NAMESIZE];
49 struct ifreq ifr;
50 int fd, ret = -1;
51
52 fd = socket(AF_INET, SOCK_DGRAM, 0);
53 if (fd < 0)
54 return ret;
55
56 if (!if_indextoname(ifindex, ifname))
57 goto err_out;
58
59 strcpy(ifr.ifr_name, ifname);
60
61 if (ioctl(fd, SIOCGIFHWADDR, &ifr) != 0)
62 goto err_out;
63
64 memcpy(mac_addr, ifr.ifr_hwaddr.sa_data, 6 * sizeof(char));
65 ret = 0;
66
67err_out:
68 close(fd);
69 return ret;
70}
71
72static void usage(const char *prog)
73{
74 fprintf(stderr,
75 "usage: %s [OPTS] <IFNAME|IFINDEX> <IFNAME|IFINDEX> ...\n"
76 "OPTS:\n"
77 " -S use skb-mode\n"
78 " -N enforce native mode\n"
79 " -F force loading prog\n"
80 " -X load xdp program on egress\n",
81 prog);
82}
83
84int main(int argc, char **argv)
85{
86 int prog_fd, group_all, mac_map;
87 struct bpf_program *ingress_prog, *egress_prog;
88 struct bpf_prog_load_attr prog_load_attr = {
89 .prog_type = BPF_PROG_TYPE_UNSPEC,
90 };
91 int i, ret, opt, egress_prog_fd = 0;
92 struct bpf_devmap_val devmap_val;
93 bool attach_egress_prog = false;
94 unsigned char mac_addr[6];
95 char ifname[IF_NAMESIZE];
96 struct bpf_object *obj;
97 unsigned int ifindex;
98 char filename[256];
99
100 while ((opt = getopt(argc, argv, "SNFX")) != -1) {
101 switch (opt) {
102 case 'S':
103 xdp_flags |= XDP_FLAGS_SKB_MODE;
104 break;
105 case 'N':
106
107 break;
108 case 'F':
109 xdp_flags &= ~XDP_FLAGS_UPDATE_IF_NOEXIST;
110 break;
111 case 'X':
112 attach_egress_prog = true;
113 break;
114 default:
115 usage(basename(argv[0]));
116 return 1;
117 }
118 }
119
120 if (!(xdp_flags & XDP_FLAGS_SKB_MODE)) {
121 xdp_flags |= XDP_FLAGS_DRV_MODE;
122 } else if (attach_egress_prog) {
123 printf("Load xdp program on egress with SKB mode not supported yet\n");
124 goto err_out;
125 }
126
127 if (optind == argc) {
128 printf("usage: %s <IFNAME|IFINDEX> <IFNAME|IFINDEX> ...\n", argv[0]);
129 goto err_out;
130 }
131
132 printf("Get interfaces");
133 for (i = 0; i < MAX_IFACE_NUM && argv[optind + i]; i++) {
134 ifaces[i] = if_nametoindex(argv[optind + i]);
135 if (!ifaces[i])
136 ifaces[i] = strtoul(argv[optind + i], NULL, 0);
137 if (!if_indextoname(ifaces[i], ifname)) {
138 perror("Invalid interface name or i");
139 goto err_out;
140 }
141 if (ifaces[i] > MAX_INDEX_NUM) {
142 printf("Interface index to large\n");
143 goto err_out;
144 }
145 printf(" %d", ifaces[i]);
146 }
147 printf("\n");
148
149 snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
150 prog_load_attr.file = filename;
151
152 if (bpf_prog_load_xattr(&prog_load_attr, &obj, &prog_fd))
153 goto err_out;
154
155 if (attach_egress_prog)
156 group_all = bpf_object__find_map_fd_by_name(obj, "map_egress");
157 else
158 group_all = bpf_object__find_map_fd_by_name(obj, "map_all");
159 mac_map = bpf_object__find_map_fd_by_name(obj, "mac_map");
160
161 if (group_all < 0 || mac_map < 0) {
162 printf("bpf_object__find_map_fd_by_name failed\n");
163 goto err_out;
164 }
165
166 if (attach_egress_prog) {
167
168 ingress_prog = bpf_object__find_program_by_name(obj, "xdp_redirect_map_all_prog");
169 egress_prog = bpf_object__find_program_by_name(obj, "xdp_devmap_prog");
170 if (!ingress_prog || !egress_prog) {
171 printf("finding ingress/egress_prog in obj file failed\n");
172 goto err_out;
173 }
174 prog_fd = bpf_program__fd(ingress_prog);
175 egress_prog_fd = bpf_program__fd(egress_prog);
176 if (prog_fd < 0 || egress_prog_fd < 0) {
177 printf("find egress_prog fd failed\n");
178 goto err_out;
179 }
180 }
181
182 signal(SIGINT, int_exit);
183 signal(SIGTERM, int_exit);
184
185
186 for (i = 0; ifaces[i] > 0; i++) {
187 ifindex = ifaces[i];
188
189 if (attach_egress_prog) {
190 ret = get_mac_addr(ifindex, mac_addr);
191 if (ret < 0) {
192 printf("get interface %d mac failed\n", ifindex);
193 goto err_out;
194 }
195 ret = bpf_map_update_elem(mac_map, &ifindex, mac_addr, 0);
196 if (ret) {
197 perror("bpf_update_elem mac_map failed\n");
198 goto err_out;
199 }
200 }
201
202
203 devmap_val.ifindex = ifindex;
204 devmap_val.bpf_prog.fd = egress_prog_fd;
205 ret = bpf_map_update_elem(group_all, &ifindex, &devmap_val, 0);
206 if (ret) {
207 perror("bpf_map_update_elem");
208 goto err_out;
209 }
210
211
212 ret = bpf_set_link_xdp_fd(ifindex, prog_fd, xdp_flags);
213 if (ret) {
214 printf("Set xdp fd failed on %d\n", ifindex);
215 goto err_out;
216 }
217 }
218
219
220 sleep(999);
221
222 return 0;
223
224err_out:
225 return 1;
226}
227
