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_xdp_query_id(ifaces[i], xdp_flags, &prog_id)) {
36 printf("bpf_xdp_query_id failed\n");
37 exit(1);
38 }
39 if (prog_id)
40 bpf_xdp_detach(ifaces[i], xdp_flags, NULL);
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 int i, err, ret, opt, egress_prog_fd = 0;
89 struct bpf_devmap_val devmap_val;
90 bool attach_egress_prog = false;
91 unsigned char mac_addr[6];
92 char ifname[IF_NAMESIZE];
93 struct bpf_object *obj;
94 unsigned int ifindex;
95 char filename[256];
96
97 while ((opt = getopt(argc, argv, "SNFX")) != -1) {
98 switch (opt) {
99 case 'S':
100 xdp_flags |= XDP_FLAGS_SKB_MODE;
101 break;
102 case 'N':
103
104 break;
105 case 'F':
106 xdp_flags &= ~XDP_FLAGS_UPDATE_IF_NOEXIST;
107 break;
108 case 'X':
109 attach_egress_prog = true;
110 break;
111 default:
112 usage(basename(argv[0]));
113 return 1;
114 }
115 }
116
117 if (!(xdp_flags & XDP_FLAGS_SKB_MODE)) {
118 xdp_flags |= XDP_FLAGS_DRV_MODE;
119 } else if (attach_egress_prog) {
120 printf("Load xdp program on egress with SKB mode not supported yet\n");
121 goto err_out;
122 }
123
124 if (optind == argc) {
125 printf("usage: %s <IFNAME|IFINDEX> <IFNAME|IFINDEX> ...\n", argv[0]);
126 goto err_out;
127 }
128
129 printf("Get interfaces:");
130 for (i = 0; i < MAX_IFACE_NUM && argv[optind + i]; i++) {
131 ifaces[i] = if_nametoindex(argv[optind + i]);
132 if (!ifaces[i])
133 ifaces[i] = strtoul(argv[optind + i], NULL, 0);
134 if (!if_indextoname(ifaces[i], ifname)) {
135 perror("Invalid interface name or i");
136 goto err_out;
137 }
138 if (ifaces[i] > MAX_INDEX_NUM) {
139 printf(" interface index too large\n");
140 goto err_out;
141 }
142 printf(" %d", ifaces[i]);
143 }
144 printf("\n");
145
146 snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
147 obj = bpf_object__open_file(filename, NULL);
148 err = libbpf_get_error(obj);
149 if (err)
150 goto err_out;
151 err = bpf_object__load(obj);
152 if (err)
153 goto err_out;
154 prog_fd = bpf_program__fd(bpf_object__next_program(obj, NULL));
155
156 if (attach_egress_prog)
157 group_all = bpf_object__find_map_fd_by_name(obj, "map_egress");
158 else
159 group_all = bpf_object__find_map_fd_by_name(obj, "map_all");
160 mac_map = bpf_object__find_map_fd_by_name(obj, "mac_map");
161
162 if (group_all < 0 || mac_map < 0) {
163 printf("bpf_object__find_map_fd_by_name failed\n");
164 goto err_out;
165 }
166
167 if (attach_egress_prog) {
168
169 ingress_prog = bpf_object__find_program_by_name(obj, "xdp_redirect_map_all_prog");
170 egress_prog = bpf_object__find_program_by_name(obj, "xdp_devmap_prog");
171 if (!ingress_prog || !egress_prog) {
172 printf("finding ingress/egress_prog in obj file failed\n");
173 goto err_out;
174 }
175 prog_fd = bpf_program__fd(ingress_prog);
176 egress_prog_fd = bpf_program__fd(egress_prog);
177 if (prog_fd < 0 || egress_prog_fd < 0) {
178 printf("find egress_prog fd failed\n");
179 goto err_out;
180 }
181 }
182
183 signal(SIGINT, int_exit);
184 signal(SIGTERM, int_exit);
185
186
187 for (i = 0; ifaces[i] > 0; i++) {
188 ifindex = ifaces[i];
189
190 if (attach_egress_prog) {
191 ret = get_mac_addr(ifindex, mac_addr);
192 if (ret < 0) {
193 printf("get interface %d mac failed\n", ifindex);
194 goto err_out;
195 }
196 ret = bpf_map_update_elem(mac_map, &ifindex, mac_addr, 0);
197 if (ret) {
198 perror("bpf_update_elem mac_map failed\n");
199 goto err_out;
200 }
201 }
202
203
204 devmap_val.ifindex = ifindex;
205 devmap_val.bpf_prog.fd = egress_prog_fd;
206 ret = bpf_map_update_elem(group_all, &ifindex, &devmap_val, 0);
207 if (ret) {
208 perror("bpf_map_update_elem");
209 goto err_out;
210 }
211
212
213 ret = bpf_xdp_attach(ifindex, prog_fd, xdp_flags, NULL);
214 if (ret) {
215 printf("Set xdp fd failed on %d\n", ifindex);
216 goto err_out;
217 }
218 }
219
220
221 sleep(999);
222
223 return 0;
224
225err_out:
226 return 1;
227}
228
