ipmaddr.c revision 1f7190db3920f76cca7fdcd1bb318c6cfa4a3266 
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
32static struct {
33	char *dev;
34	int  family;
35} filter;
36
37static void usage(void) __attribute__((noreturn));
38
39static void usage(void)
40{
41	fprintf(stderr, "Usage: ip maddr [ add | del ] MULTIADDR dev STRING\n");
42	fprintf(stderr, "       ip maddr show [ dev STRING ]\n");
43	exit(-1);
44}
45
46static int parse_hex(char *str, unsigned char *addr, size_t size)
47{
48	int len=0;
49
50	while (*str && (len < 2 * size)) {
51		int tmp;
52		if (str[1] == 0)
53			return -1;
54		if (sscanf(str, "%02x", &tmp) != 1)
55			return -1;
56		addr[len] = tmp;
57		len++;
58		str += 2;
59	}
60	return len;
61}
62
63struct ma_info
64{
65	struct ma_info *next;
66	int		index;
67	int		users;
68	char		*features;
69	char		name[IFNAMSIZ];
70	inet_prefix	addr;
71};
72
73void maddr_ins(struct ma_info **lst, struct ma_info *m)
74{
75	struct ma_info *mp;
76
77	for (; (mp=*lst) != NULL; lst = &mp->next) {
78		if (mp->index > m->index)
79			break;
80	}
81	m->next = *lst;
82	*lst = m;
83}
84
85void read_dev_mcast(struct ma_info **result_p)
86{
87	char buf[256];
88	FILE *fp = fopen("/proc/net/dev_mcast", "r");
89
90	if (!fp)
91		return;
92
93	while (fgets(buf, sizeof(buf), fp)) {
94		char hexa[256];
95		struct ma_info m;
96		int len;
97		int st;
98
99		memset(&m, 0, sizeof(m));
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		m.addr.family = AF_PACKET;
106
107		len = parse_hex(hexa, (unsigned char*)&m.addr.data, sizeof (m.addr.data));
108		if (len >= 0) {
109			struct ma_info *ma = malloc(sizeof(m));
110
111			memcpy(ma, &m, sizeof(m));
112			ma->addr.bytelen = len;
113			ma->addr.bitlen = len<<3;
114			if (st)
115				ma->features = "static";
116			maddr_ins(result_p, ma);
117		}
118	}
119	fclose(fp);
120}
121
122void read_igmp(struct ma_info **result_p)
123{
124	struct ma_info m;
125	char buf[256];
126	FILE *fp = fopen("/proc/net/igmp", "r");
127
128	if (!fp)
129		return;
130	memset(&m, 0, sizeof(m));
131	if (!fgets(buf, sizeof(buf), fp))
132		return;
133
134	m.addr.family = AF_INET;
135	m.addr.bitlen = 32;
136	m.addr.bytelen = 4;
137
138	while (fgets(buf, sizeof(buf), fp)) {
139		struct ma_info *ma;
140
141		if (buf[0] != '\t') {
142			sscanf(buf, "%d%s", &m.index, m.name);
143			continue;
144		}
145
146		if (filter.dev && strcmp(filter.dev, m.name))
147			continue;
148
149		sscanf(buf, "%08x%d", (__u32*)&m.addr.data, &m.users);
150
151		ma = malloc(sizeof(m));
152		memcpy(ma, &m, sizeof(m));
153		maddr_ins(result_p, ma);
154	}
155	fclose(fp);
156}
157
158
159void read_igmp6(struct ma_info **result_p)
160{
161	char buf[256];
162	FILE *fp = fopen("/proc/net/igmp6", "r");
163
164	if (!fp)
165		return;
166
167	while (fgets(buf, sizeof(buf), fp)) {
168		char hexa[256];
169		struct ma_info m;
170		int len;
171
172		memset(&m, 0, sizeof(m));
173		sscanf(buf, "%d%s%s%d", &m.index, m.name, hexa, &m.users);
174
175		if (filter.dev && strcmp(filter.dev, m.name))
176			continue;
177
178		m.addr.family = AF_INET6;
179
180		len = parse_hex(hexa, (unsigned char*)&m.addr.data, sizeof (m.addr.data));
181		if (len >= 0) {
182			struct ma_info *ma = malloc(sizeof(m));
183
184			memcpy(ma, &m, sizeof(m));
185
186			ma->addr.bytelen = len;
187			ma->addr.bitlen = len<<3;
188			maddr_ins(result_p, ma);
189		}
190	}
191	fclose(fp);
192}
193
194static void print_maddr(FILE *fp, struct ma_info *list)
195{
196	fprintf(fp, "\t");
197
198	if (list->addr.family == AF_PACKET) {
199		SPRINT_BUF(b1);
200		fprintf(fp, "link  %s", ll_addr_n2a((unsigned char*)list->addr.data,
201						    list->addr.bytelen, 0,
202						    b1, sizeof(b1)));
203	} else {
204		char abuf[256];
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,
219				    list->addr.data,
220				    abuf, sizeof(abuf)));
221	}
222	if (list->users != 1)
223		fprintf(fp, " users %d", list->users);
224	if (list->features)
225		fprintf(fp, " %s", list->features);
226	fprintf(fp, "\n");
227}
228
229static void print_mlist(FILE *fp, struct ma_info *list)
230{
231	int cur_index = 0;
232
233	for (; list; list = list->next) {
234		if (oneline) {
235			cur_index = list->index;
236			fprintf(fp, "%d:\t%s%s", cur_index, list->name, _SL_);
237		} else if (cur_index != list->index) {
238			cur_index = list->index;
239			fprintf(fp, "%d:\t%s\n", cur_index, list->name);
240		}
241		print_maddr(fp, list);
242	}
243}
244
245static int multiaddr_list(int argc, char **argv)
246{
247	struct ma_info *list = NULL;
248
249	if (!filter.family)
250		filter.family = preferred_family;
251
252	while (argc > 0) {
253		if (1) {
254			if (strcmp(*argv, "dev") == 0) {
255				NEXT_ARG();
256			}
257			if (matches(*argv, "help") == 0)
258				usage();
259			if (filter.dev)
260				duparg2("dev", *argv);
261			filter.dev = *argv;
262		}
263		argv++; argc--;
264	}
265
266	if (!filter.family || filter.family == AF_PACKET)
267		read_dev_mcast(&list);
268	if (!filter.family || filter.family == AF_INET)
269		read_igmp(&list);
270	if (!filter.family || filter.family == AF_INET6)
271		read_igmp6(&list);
272	print_mlist(stdout, list);
273	return 0;
274}
275
276int multiaddr_modify(int cmd, int argc, char **argv)
277{
278	struct ifreq ifr;
279	int fd;
280
281	memset(&ifr, 0, sizeof(ifr));
282
283	if (cmd == RTM_NEWADDR)
284		cmd = SIOCADDMULTI;
285	else
286		cmd = SIOCDELMULTI;
287
288	while (argc > 0) {
289		if (strcmp(*argv, "dev") == 0) {
290			NEXT_ARG();
291			if (ifr.ifr_name[0])
292				duparg("dev", *argv);
293			strncpy(ifr.ifr_name, *argv, IFNAMSIZ);
294		} else {
295			if (matches(*argv, "address") == 0) {
296				NEXT_ARG();
297			}
298			if (matches(*argv, "help") == 0)
299				usage();
300			if (ifr.ifr_hwaddr.sa_data[0])
301				duparg("address", *argv);
302			if (ll_addr_a2n(ifr.ifr_hwaddr.sa_data,
303					14, *argv) < 0) {
304				fprintf(stderr, "Error: \"%s\" is not a legal ll address.\n", *argv);
305				exit(1);
306			}
307		}
308		argc--; argv++;
309	}
310	if (ifr.ifr_name[0] == 0) {
311		fprintf(stderr, "Not enough information: \"dev\" is required.\n");
312		exit(-1);
313	}
314
315	fd = socket(AF_INET, SOCK_DGRAM, 0);
316	if (fd < 0) {
317		perror("Cannot create socket");
318		exit(1);
319	}
320	if (ioctl(fd, cmd, (char*)&ifr) != 0) {
321		perror("ioctl");
322		exit(1);
323	}
324	close(fd);
325
326	exit(0);
327}
328
329
330int do_multiaddr(int argc, char **argv)
331{
332	if (argc < 1)
333		return multiaddr_list(0, NULL);
334	if (matches(*argv, "add") == 0)
335		return multiaddr_modify(RTM_NEWADDR, argc-1, argv+1);
336	if (matches(*argv, "delete") == 0)
337		return multiaddr_modify(RTM_DELADDR, argc-1, argv+1);
338	if (matches(*argv, "list") == 0 || matches(*argv, "show") == 0
339	    || matches(*argv, "lst") == 0)
340		return multiaddr_list(argc-1, argv+1);
341	if (matches(*argv, "help") == 0)
342		usage();
343	fprintf(stderr, "Command \"%s\" is unknown, try \"ip maddr help\".\n", *argv);
344	exit(-1);
345}
346