1 | // SPDX-License-Identifier: GPL-2.0 |
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/ioctl.h> |
14 | #include <sys/types.h> |
15 | #include <sys/socket.h> |
16 | #include <netinet/in.h> |
17 | |
18 | #include "bpf_util.h" |
19 | #include <bpf/bpf.h> |
20 | #include <bpf/libbpf.h> |
21 | |
22 | #define MAX_IFACE_NUM 32 |
23 | #define MAX_INDEX_NUM 1024 |
24 | |
25 | static __u32 xdp_flags = XDP_FLAGS_UPDATE_IF_NOEXIST; |
26 | static int ifaces[MAX_IFACE_NUM] = {}; |
27 | |
28 | static void int_exit(int sig) |
29 | { |
30 | __u32 prog_id = 0; |
31 | int i; |
32 | |
33 | for (i = 0; ifaces[i] > 0; i++) { |
34 | if (bpf_xdp_query_id(ifaces[i], xdp_flags, &prog_id)) { |
35 | printf("bpf_xdp_query_id failed\n" ); |
36 | exit(1); |
37 | } |
38 | if (prog_id) |
39 | bpf_xdp_detach(ifaces[i], xdp_flags, NULL); |
40 | } |
41 | |
42 | exit(0); |
43 | } |
44 | |
45 | static int get_mac_addr(unsigned int ifindex, void *mac_addr) |
46 | { |
47 | char ifname[IF_NAMESIZE]; |
48 | struct ifreq ifr; |
49 | int fd, ret = -1; |
50 | |
51 | fd = socket(AF_INET, SOCK_DGRAM, 0); |
52 | if (fd < 0) |
53 | return ret; |
54 | |
55 | if (!if_indextoname(ifindex, ifname)) |
56 | goto err_out; |
57 | |
58 | strcpy(ifr.ifr_name, ifname); |
59 | |
60 | if (ioctl(fd, SIOCGIFHWADDR, &ifr) != 0) |
61 | goto err_out; |
62 | |
63 | memcpy(mac_addr, ifr.ifr_hwaddr.sa_data, 6 * sizeof(char)); |
64 | ret = 0; |
65 | |
66 | err_out: |
67 | close(fd); |
68 | return ret; |
69 | } |
70 | |
71 | static void usage(const char *prog) |
72 | { |
73 | fprintf(stderr, |
74 | "usage: %s [OPTS] <IFNAME|IFINDEX> <IFNAME|IFINDEX> ...\n" |
75 | "OPTS:\n" |
76 | " -S use skb-mode\n" |
77 | " -N enforce native mode\n" |
78 | " -F force loading prog\n" |
79 | " -X load xdp program on egress\n" , |
80 | prog); |
81 | } |
82 | |
83 | int main(int argc, char **argv) |
84 | { |
85 | int prog_fd, group_all, mac_map; |
86 | struct bpf_program *ingress_prog, *egress_prog; |
87 | int i, err, ret, opt, egress_prog_fd = 0; |
88 | struct bpf_devmap_val devmap_val; |
89 | bool attach_egress_prog = false; |
90 | unsigned char mac_addr[6]; |
91 | char ifname[IF_NAMESIZE]; |
92 | struct bpf_object *obj; |
93 | unsigned int ifindex; |
94 | char filename[256]; |
95 | |
96 | while ((opt = getopt(argc, argv, "SNFX" )) != -1) { |
97 | switch (opt) { |
98 | case 'S': |
99 | xdp_flags |= XDP_FLAGS_SKB_MODE; |
100 | break; |
101 | case 'N': |
102 | /* default, set below */ |
103 | break; |
104 | case 'F': |
105 | xdp_flags &= ~XDP_FLAGS_UPDATE_IF_NOEXIST; |
106 | break; |
107 | case 'X': |
108 | attach_egress_prog = true; |
109 | break; |
110 | default: |
111 | usage(prog: basename(argv[0])); |
112 | return 1; |
113 | } |
114 | } |
115 | |
116 | if (!(xdp_flags & XDP_FLAGS_SKB_MODE)) { |
117 | xdp_flags |= XDP_FLAGS_DRV_MODE; |
118 | } else if (attach_egress_prog) { |
119 | printf("Load xdp program on egress with SKB mode not supported yet\n" ); |
120 | goto err_out; |
121 | } |
122 | |
123 | if (optind == argc) { |
124 | printf("usage: %s <IFNAME|IFINDEX> <IFNAME|IFINDEX> ...\n" , argv[0]); |
125 | goto err_out; |
126 | } |
127 | |
128 | printf("Get interfaces:" ); |
129 | for (i = 0; i < MAX_IFACE_NUM && argv[optind + i]; i++) { |
130 | ifaces[i] = if_nametoindex(argv[optind + i]); |
131 | if (!ifaces[i]) |
132 | ifaces[i] = strtoul(argv[optind + i], NULL, 0); |
133 | if (!if_indextoname(ifaces[i], ifname)) { |
134 | perror("Invalid interface name or i" ); |
135 | goto err_out; |
136 | } |
137 | if (ifaces[i] > MAX_INDEX_NUM) { |
138 | printf(" interface index too large\n" ); |
139 | goto err_out; |
140 | } |
141 | printf(" %d" , ifaces[i]); |
142 | } |
143 | printf("\n" ); |
144 | |
145 | snprintf(buf: filename, size: sizeof(filename), fmt: "%s_kern.bpf.o" , argv[0]); |
146 | obj = bpf_object__open_file(filename, NULL); |
147 | err = libbpf_get_error(obj); |
148 | if (err) |
149 | goto err_out; |
150 | err = bpf_object__load(obj); |
151 | if (err) |
152 | goto err_out; |
153 | prog_fd = bpf_program__fd(bpf_object__next_program(obj, NULL)); |
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 | /* Find ingress/egress prog for 2nd xdp prog */ |
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 | /* Init forward multicast groups and exclude group */ |
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 | /* Add all the interfaces to group all */ |
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 | /* bind prog_fd to each interface */ |
212 | ret = bpf_xdp_attach(ifindex, prog_fd, xdp_flags, NULL); |
213 | if (ret) { |
214 | printf("Set xdp fd failed on %d\n" , ifindex); |
215 | goto err_out; |
216 | } |
217 | } |
218 | |
219 | /* sleep some time for testing */ |
220 | sleep(999); |
221 | |
222 | return 0; |
223 | |
224 | err_out: |
225 | return 1; |
226 | } |
227 | |