1 /*
2 * ipmaddr.c "ip maddress".
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
8 *
9 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
10 *
11 */
12
13 #include <stdio.h>
14 #include <stdlib.h>
15 #include <unistd.h>
16 #include <syslog.h>
17 #include <fcntl.h>
18 #include <sys/ioctl.h>
19 #include <sys/socket.h>
20 #include <netinet/in.h>
21 #include <arpa/inet.h>
22 #include <string.h>
23
24 #include <linux/netdevice.h>
25 #include <linux/if.h>
26 #include <linux/if_arp.h>
27 #include <linux/sockios.h>
28
29 #include "rt_names.h"
30 #include "utils.h"
31 #include "ip_common.h"
32
33 static struct {
34 char *dev;
35 int family;
36 } filter;
37
38 static void usage(void) __attribute__((noreturn));
39
usage(void)40 static void usage(void)
41 {
42 fprintf(stderr, "Usage: ip maddr [ add | del ] MULTIADDR dev STRING\n");
43 fprintf(stderr, " ip maddr show [ dev STRING ]\n");
44 exit(-1);
45 }
46
parse_hex(char * str,unsigned char * addr,size_t size)47 static int parse_hex(char *str, unsigned char *addr, size_t size)
48 {
49 int len = 0;
50
51 while (*str && (len < 2 * size)) {
52 int tmp;
53
54 if (str[1] == 0)
55 return -1;
56 if (sscanf(str, "%02x", &tmp) != 1)
57 return -1;
58 addr[len] = tmp;
59 len++;
60 str += 2;
61 }
62 return len;
63 }
64
65 struct ma_info {
66 struct ma_info *next;
67 int index;
68 int users;
69 char *features;
70 char name[IFNAMSIZ];
71 inet_prefix addr;
72 };
73
maddr_ins(struct ma_info ** lst,struct ma_info * m)74 static void maddr_ins(struct ma_info **lst, struct ma_info *m)
75 {
76 struct ma_info *mp;
77
78 for (; (mp = *lst) != NULL; lst = &mp->next) {
79 if (mp->index > m->index)
80 break;
81 }
82 m->next = *lst;
83 *lst = m;
84 }
85
read_dev_mcast(struct ma_info ** result_p)86 static void read_dev_mcast(struct ma_info **result_p)
87 {
88 char buf[256];
89 FILE *fp = fopen("/proc/net/dev_mcast", "r");
90
91 if (!fp)
92 return;
93
94 while (fgets(buf, sizeof(buf), fp)) {
95 char hexa[256];
96 struct ma_info m = { .addr.family = AF_PACKET };
97 int len;
98 int st;
99
100 sscanf(buf, "%d%s%d%d%s", &m.index, m.name, &m.users, &st,
101 hexa);
102 if (filter.dev && strcmp(filter.dev, m.name))
103 continue;
104
105 len = parse_hex(hexa, (unsigned char *)&m.addr.data, sizeof(m.addr.data));
106 if (len >= 0) {
107 struct ma_info *ma = malloc(sizeof(m));
108
109 memcpy(ma, &m, sizeof(m));
110 ma->addr.bytelen = len;
111 ma->addr.bitlen = len<<3;
112 if (st)
113 ma->features = "static";
114 maddr_ins(result_p, ma);
115 }
116 }
117 fclose(fp);
118 }
119
read_igmp(struct ma_info ** result_p)120 static void read_igmp(struct ma_info **result_p)
121 {
122 struct ma_info m = {
123 .addr.family = AF_INET,
124 .addr.bitlen = 32,
125 .addr.bytelen = 4,
126 };
127 char buf[256];
128 FILE *fp = fopen("/proc/net/igmp", "r");
129
130 if (!fp)
131 return;
132 if (!fgets(buf, sizeof(buf), fp)) {
133 fclose(fp);
134 return;
135 }
136
137 while (fgets(buf, sizeof(buf), fp)) {
138 struct ma_info *ma;
139
140 if (buf[0] != '\t') {
141 size_t len;
142
143 sscanf(buf, "%d%s", &m.index, m.name);
144 len = strlen(m.name);
145 if (m.name[len - 1] == ':')
146 m.name[len - 1] = '\0';
147 continue;
148 }
149
150 if (filter.dev && strcmp(filter.dev, m.name))
151 continue;
152
153 sscanf(buf, "%08x%d", (__u32 *)&m.addr.data, &m.users);
154
155 ma = malloc(sizeof(m));
156 memcpy(ma, &m, sizeof(m));
157 maddr_ins(result_p, ma);
158 }
159 fclose(fp);
160 }
161
162
read_igmp6(struct ma_info ** result_p)163 static void read_igmp6(struct ma_info **result_p)
164 {
165 char buf[256];
166 FILE *fp = fopen("/proc/net/igmp6", "r");
167
168 if (!fp)
169 return;
170
171 while (fgets(buf, sizeof(buf), fp)) {
172 char hexa[256];
173 struct ma_info m = { .addr.family = AF_INET6 };
174 int len;
175
176 sscanf(buf, "%d%s%s%d", &m.index, m.name, hexa, &m.users);
177
178 if (filter.dev && strcmp(filter.dev, m.name))
179 continue;
180
181 len = parse_hex(hexa, (unsigned char *)&m.addr.data, sizeof(m.addr.data));
182 if (len >= 0) {
183 struct ma_info *ma = malloc(sizeof(m));
184
185 memcpy(ma, &m, sizeof(m));
186
187 ma->addr.bytelen = len;
188 ma->addr.bitlen = len<<3;
189 maddr_ins(result_p, ma);
190 }
191 }
192 fclose(fp);
193 }
194
print_maddr(FILE * fp,struct ma_info * list)195 static void print_maddr(FILE *fp, struct ma_info *list)
196 {
197 fprintf(fp, "\t");
198
199 if (list->addr.family == AF_PACKET) {
200 SPRINT_BUF(b1);
201 fprintf(fp, "link %s", ll_addr_n2a((unsigned char *)list->addr.data,
202 list->addr.bytelen, 0,
203 b1, sizeof(b1)));
204 } else {
205 switch (list->addr.family) {
206 case AF_INET:
207 fprintf(fp, "inet ");
208 break;
209 case AF_INET6:
210 fprintf(fp, "inet6 ");
211 break;
212 default:
213 fprintf(fp, "family %d ", list->addr.family);
214 break;
215 }
216 fprintf(fp, "%s",
217 format_host(list->addr.family,
218 -1, list->addr.data));
219 }
220 if (list->users != 1)
221 fprintf(fp, " users %d", list->users);
222 if (list->features)
223 fprintf(fp, " %s", list->features);
224 fprintf(fp, "\n");
225 }
226
print_mlist(FILE * fp,struct ma_info * list)227 static void print_mlist(FILE *fp, struct ma_info *list)
228 {
229 int cur_index = 0;
230
231 for (; list; list = list->next) {
232 if (oneline) {
233 cur_index = list->index;
234 fprintf(fp, "%d:\t%s%s", cur_index, list->name, _SL_);
235 } else if (cur_index != list->index) {
236 cur_index = list->index;
237 fprintf(fp, "%d:\t%s\n", cur_index, list->name);
238 }
239 print_maddr(fp, list);
240 }
241 }
242
multiaddr_list(int argc,char ** argv)243 static int multiaddr_list(int argc, char **argv)
244 {
245 struct ma_info *list = NULL;
246
247 if (!filter.family)
248 filter.family = preferred_family;
249
250 while (argc > 0) {
251 if (1) {
252 if (strcmp(*argv, "dev") == 0) {
253 NEXT_ARG();
254 } else if (matches(*argv, "help") == 0)
255 usage();
256 if (filter.dev)
257 duparg2("dev", *argv);
258 filter.dev = *argv;
259 }
260 argv++; argc--;
261 }
262
263 if (!filter.family || filter.family == AF_PACKET)
264 read_dev_mcast(&list);
265 if (!filter.family || filter.family == AF_INET)
266 read_igmp(&list);
267 if (!filter.family || filter.family == AF_INET6)
268 read_igmp6(&list);
269 print_mlist(stdout, list);
270 return 0;
271 }
272
multiaddr_modify(int cmd,int argc,char ** argv)273 static int multiaddr_modify(int cmd, int argc, char **argv)
274 {
275 struct ifreq ifr = {};
276 int fd;
277
278 if (cmd == RTM_NEWADDR)
279 cmd = SIOCADDMULTI;
280 else
281 cmd = SIOCDELMULTI;
282
283 while (argc > 0) {
284 if (strcmp(*argv, "dev") == 0) {
285 NEXT_ARG();
286 if (ifr.ifr_name[0])
287 duparg("dev", *argv);
288 if (get_ifname(ifr.ifr_name, *argv))
289 invarg("\"dev\" not a valid ifname", *argv);
290 } else {
291 if (matches(*argv, "address") == 0) {
292 NEXT_ARG();
293 }
294 if (matches(*argv, "help") == 0)
295 usage();
296 if (ifr.ifr_hwaddr.sa_data[0])
297 duparg("address", *argv);
298 if (ll_addr_a2n(ifr.ifr_hwaddr.sa_data,
299 14, *argv) < 0) {
300 fprintf(stderr, "Error: \"%s\" is not a legal ll address.\n", *argv);
301 exit(1);
302 }
303 }
304 argc--; argv++;
305 }
306 if (ifr.ifr_name[0] == 0) {
307 fprintf(stderr, "Not enough information: \"dev\" is required.\n");
308 exit(-1);
309 }
310
311 fd = socket(AF_INET, SOCK_DGRAM, 0);
312 if (fd < 0) {
313 perror("Cannot create socket");
314 exit(1);
315 }
316 if (ioctl(fd, cmd, (char *)&ifr) != 0) {
317 perror("ioctl");
318 exit(1);
319 }
320 close(fd);
321
322 exit(0);
323 }
324
325
do_multiaddr(int argc,char ** argv)326 int do_multiaddr(int argc, char **argv)
327 {
328 if (argc < 1)
329 return multiaddr_list(0, NULL);
330 if (matches(*argv, "add") == 0)
331 return multiaddr_modify(RTM_NEWADDR, argc-1, argv+1);
332 if (matches(*argv, "delete") == 0)
333 return multiaddr_modify(RTM_DELADDR, argc-1, argv+1);
334 if (matches(*argv, "list") == 0 || matches(*argv, "show") == 0
335 || matches(*argv, "lst") == 0)
336 return multiaddr_list(argc-1, argv+1);
337 if (matches(*argv, "help") == 0)
338 usage();
339 fprintf(stderr, "Command \"%s\" is unknown, try \"ip maddr help\".\n", *argv);
340 exit(-1);
341 }
342