aboutsummaryrefslogtreecommitdiff
path: root/networking/libiproute/iplink.c
blob: 2797f0250df3ce88c6a15093daeee9f5fb0d9ecc (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
/*
 * iplink.c		"ip link".
 *
 * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
 *
 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
 */

#include "libbb.h"

#include <sys/ioctl.h>
#include <sys/socket.h>

#include <errno.h>
#include <string.h>
#include <unistd.h>

#include <net/if.h>
#include <net/if_packet.h>
#include <netpacket/packet.h>

#include <net/ethernet.h>

#include "rt_names.h"
#include "utils.h"
#include "ip_common.h"

/* take from linux/sockios.h */
#define SIOCSIFNAME	0x8923		/* set interface name */

static int do_link;

static int on_off(char *msg)
{
	bb_error_msg("Error: argument of \"%s\" must be \"on\" or \"off\"", msg);
	return -1;
}

static int get_ctl_fd(void)
{
	int s_errno;
	int fd;

	fd = socket(PF_INET, SOCK_DGRAM, 0);
	if (fd >= 0)
		return fd;
	s_errno = errno;
	fd = socket(PF_PACKET, SOCK_DGRAM, 0);
	if (fd >= 0)
		return fd;
	fd = socket(PF_INET6, SOCK_DGRAM, 0);
	if (fd >= 0)
		return fd;
	errno = s_errno;
	perror("Cannot create control socket");
	return -1;
}

static int do_chflags(char *dev, __u32 flags, __u32 mask)
{
	struct ifreq ifr;
	int fd;
	int err;

	strcpy(ifr.ifr_name, dev);
	fd = get_ctl_fd();
	if (fd < 0)
		return -1;
	err = ioctl(fd, SIOCGIFFLAGS, &ifr);
	if (err) {
		perror("SIOCGIFFLAGS");
		close(fd);
		return -1;
	}
	if ((ifr.ifr_flags^flags)&mask) {
		ifr.ifr_flags &= ~mask;
		ifr.ifr_flags |= mask&flags;
		err = ioctl(fd, SIOCSIFFLAGS, &ifr);
		if (err)
			perror("SIOCSIFFLAGS");
	}
	close(fd);
	return err;
}

static int do_changename(char *dev, char *newdev)
{
	struct ifreq ifr;
	int fd;
	int err;

	strcpy(ifr.ifr_name, dev);
	strcpy(ifr.ifr_newname, newdev);
	fd = get_ctl_fd();
	if (fd < 0)
		return -1;
	err = ioctl(fd, SIOCSIFNAME, &ifr);
	if (err) {
		perror("SIOCSIFNAME");
		close(fd);
		return -1;
	}
	close(fd);
	return err;
}

static int set_qlen(char *dev, int qlen)
{
	struct ifreq ifr;
	int s;

	s = get_ctl_fd();
	if (s < 0)
		return -1;

	memset(&ifr, 0, sizeof(ifr));
	strcpy(ifr.ifr_name, dev);
	ifr.ifr_qlen = qlen;
	if (ioctl(s, SIOCSIFTXQLEN, &ifr) < 0) {
		perror("SIOCSIFXQLEN");
		close(s);
		return -1;
	}
	close(s);

	return 0;
}

static int set_mtu(char *dev, int mtu)
{
	struct ifreq ifr;
	int s;

	s = get_ctl_fd();
	if (s < 0)
		return -1;

	memset(&ifr, 0, sizeof(ifr));
	strcpy(ifr.ifr_name, dev);
	ifr.ifr_mtu = mtu;
	if (ioctl(s, SIOCSIFMTU, &ifr) < 0) {
		perror("SIOCSIFMTU");
		close(s);
		return -1;
	}
	close(s);

	return 0;
}

static int get_address(char *dev, int *htype)
{
	struct ifreq ifr;
	struct sockaddr_ll me;
	socklen_t alen;
	int s;

	s = socket(PF_PACKET, SOCK_DGRAM, 0);
	if (s < 0) {
		perror("socket(PF_PACKET)");
		return -1;
	}

	memset(&ifr, 0, sizeof(ifr));
	strcpy(ifr.ifr_name, dev);
	if (ioctl(s, SIOCGIFINDEX, &ifr) < 0) {
		perror("SIOCGIFINDEX");
		close(s);
		return -1;
	}

	memset(&me, 0, sizeof(me));
	me.sll_family = AF_PACKET;
	me.sll_ifindex = ifr.ifr_ifindex;
	me.sll_protocol = htons(ETH_P_LOOP);
	if (bind(s, (struct sockaddr*)&me, sizeof(me)) == -1) {
		perror("bind");
		close(s);
		return -1;
	}

	alen = sizeof(me);
	if (getsockname(s, (struct sockaddr*)&me, &alen) == -1) {
		perror("getsockname");
		close(s);
		return -1;
	}
	close(s);
	*htype = me.sll_hatype;
	return me.sll_halen;
}

static int parse_address(char *dev, int hatype, int halen, char *lla, struct ifreq *ifr)
{
	int alen;

	memset(ifr, 0, sizeof(*ifr));
	strcpy(ifr->ifr_name, dev);
	ifr->ifr_hwaddr.sa_family = hatype;
	alen = ll_addr_a2n((unsigned char *)(ifr->ifr_hwaddr.sa_data), 14, lla);
	if (alen < 0)
		return -1;
	if (alen != halen) {
		bb_error_msg("Wrong address (%s) length: expected %d bytes", lla, halen);
		return -1;
	}
	return 0;
}

static int set_address(struct ifreq *ifr, int brd)
{
	int s;

	s = get_ctl_fd();
	if (s < 0)
		return -1;
	if (ioctl(s, brd?SIOCSIFHWBROADCAST:SIOCSIFHWADDR, ifr) < 0) {
		perror(brd?"SIOCSIFHWBROADCAST":"SIOCSIFHWADDR");
		close(s);
		return -1;
	}
	close(s);
	return 0;
}


static int do_set(int argc, char **argv)
{
	char *dev = NULL;
	__u32 mask = 0;
	__u32 flags = 0;
	int qlen = -1;
	int mtu = -1;
	char *newaddr = NULL;
	char *newbrd = NULL;
	struct ifreq ifr0, ifr1;
	char *newname = NULL;
	int htype, halen;

	while (argc > 0) {
		if (strcmp(*argv, "up") == 0) {
			mask |= IFF_UP;
			flags |= IFF_UP;
		} else if (strcmp(*argv, "down") == 0) {
			mask |= IFF_UP;
			flags &= ~IFF_UP;
		} else if (strcmp(*argv, "name") == 0) {
			NEXT_ARG();
			newname = *argv;
		} else if (strcmp(*argv, "mtu") == 0) {
			NEXT_ARG();
			if (mtu != -1)
				duparg("mtu", *argv);
			if (get_integer(&mtu, *argv, 0))
				invarg("Invalid \"mtu\" value\n", *argv);
		} else if (strcmp(*argv, "multicast") == 0) {
			NEXT_ARG();
			mask |= IFF_MULTICAST;
			if (strcmp(*argv, "on") == 0) {
				flags |= IFF_MULTICAST;
			} else if (strcmp(*argv, "off") == 0) {
				flags &= ~IFF_MULTICAST;
			} else
				return on_off("multicast");
		} else if (strcmp(*argv, "arp") == 0) {
			NEXT_ARG();
			mask |= IFF_NOARP;
			if (strcmp(*argv, "on") == 0) {
				flags &= ~IFF_NOARP;
			} else if (strcmp(*argv, "off") == 0) {
				flags |= IFF_NOARP;
			} else
				return on_off("noarp");
		} else if (strcmp(*argv, "addr") == 0) {
			NEXT_ARG();
			newaddr = *argv;
		} else {
			if (strcmp(*argv, "dev") == 0) {
				NEXT_ARG();
			}
			if (dev)
				duparg2("dev", *argv);
			dev = *argv;
		}
		argc--; argv++;
	}

	if (!dev) {
		bb_error_msg("Not enough of information: \"dev\" argument is required.");
		exit(-1);
	}

	if (newaddr || newbrd) {
		halen = get_address(dev, &htype);
		if (halen < 0)
			return -1;
		if (newaddr) {
			if (parse_address(dev, htype, halen, newaddr, &ifr0) < 0)
				return -1;
		}
		if (newbrd) {
			if (parse_address(dev, htype, halen, newbrd, &ifr1) < 0)
				return -1;
		}
	}

	if (newname && strcmp(dev, newname)) {
		if (do_changename(dev, newname) < 0)
			return -1;
		dev = newname;
	}
	if (qlen != -1) {
		if (set_qlen(dev, qlen) < 0)
			return -1;
	}
	if (mtu != -1) {
		if (set_mtu(dev, mtu) < 0)
			return -1;
	}
	if (newaddr || newbrd) {
		if (newbrd) {
			if (set_address(&ifr1, 1) < 0)
				return -1;
		}
		if (newaddr) {
			if (set_address(&ifr0, 0) < 0)
				return -1;
		}
	}
	if (mask)
		return do_chflags(dev, flags, mask);
	return 0;
}

static int ipaddr_list_link(int argc, char **argv)
{
	preferred_family = AF_PACKET;
	do_link = 1;
	return ipaddr_list_or_flush(argc, argv, 0);
}

int do_iplink(int argc, char **argv)
{
	if (argc > 0) {
		if (matches(*argv, "set") == 0)
			return do_set(argc-1, argv+1);
		if (matches(*argv, "show") == 0 ||
		    matches(*argv, "lst") == 0 ||
		    matches(*argv, "list") == 0)
			return ipaddr_list_link(argc-1, argv+1);
	} else
		return ipaddr_list_link(0, NULL);

	bb_error_msg("Command \"%s\" is unknown.", *argv);
	exit(-1);
}