Linux Audio

Check our new training course

Embedded Linux Audio

Check our new training course
with Creative Commons CC-BY-SA
lecture materials

Bootlin logo

Elixir Cross Referencer

Loading...
  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
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
/* vi: set sw=4 ts=4: */
/*
 * libnetlink.c	RTnetlink service routines.
 *
 *		This program is free software; you can redistribute it and/or
 *		modify it under the terms of the GNU General Public License
 *		as published by the Free Software Foundation; either version
 *		2 of the License, or (at your option) any later version.
 *
 * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
 *
 */

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

#include "libbb.h"
#include "libnetlink.h"

void FAST_FUNC rtnl_close(struct rtnl_handle *rth)
{
	close(rth->fd);
}

int FAST_FUNC xrtnl_open(struct rtnl_handle *rth/*, unsigned subscriptions*/)
{
	socklen_t addr_len;

	memset(rth, 0, sizeof(rth));

	rth->fd = xsocket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);

	memset(&rth->local, 0, sizeof(rth->local));
	rth->local.nl_family = AF_NETLINK;
	/*rth->local.nl_groups = subscriptions;*/

	xbind(rth->fd, (struct sockaddr*)&rth->local, sizeof(rth->local));
	addr_len = sizeof(rth->local);
	if (getsockname(rth->fd, (struct sockaddr*)&rth->local, &addr_len) < 0)
		bb_perror_msg_and_die("getsockname");
	if (addr_len != sizeof(rth->local))
		bb_error_msg_and_die("wrong address length %d", addr_len);
	if (rth->local.nl_family != AF_NETLINK)
		bb_error_msg_and_die("wrong address family %d", rth->local.nl_family);
	rth->seq = time(NULL);
	return 0;
}

int FAST_FUNC xrtnl_wilddump_request(struct rtnl_handle *rth, int family, int type)
{
	struct {
		struct nlmsghdr nlh;
		struct rtgenmsg g;
	} req;
	struct sockaddr_nl nladdr;

	memset(&nladdr, 0, sizeof(nladdr));
	nladdr.nl_family = AF_NETLINK;

	req.nlh.nlmsg_len = sizeof(req);
	req.nlh.nlmsg_type = type;
	req.nlh.nlmsg_flags = NLM_F_ROOT|NLM_F_MATCH|NLM_F_REQUEST;
	req.nlh.nlmsg_pid = 0;
	req.nlh.nlmsg_seq = rth->dump = ++rth->seq;
	req.g.rtgen_family = family;

	return xsendto(rth->fd, (void*)&req, sizeof(req),
				 (struct sockaddr*)&nladdr, sizeof(nladdr));
}

int FAST_FUNC rtnl_send(struct rtnl_handle *rth, char *buf, int len)
{
	struct sockaddr_nl nladdr;

	memset(&nladdr, 0, sizeof(nladdr));
	nladdr.nl_family = AF_NETLINK;

	return xsendto(rth->fd, buf, len, (struct sockaddr*)&nladdr, sizeof(nladdr));
}

int FAST_FUNC rtnl_dump_request(struct rtnl_handle *rth, int type, void *req, int len)
{
	struct nlmsghdr nlh;
	struct sockaddr_nl nladdr;
	struct iovec iov[2] = { { &nlh, sizeof(nlh) }, { req, len } };
	struct msghdr msg = {
		(void*)&nladdr, sizeof(nladdr),
		iov,	2,
		NULL,	0,
		0
	};

	memset(&nladdr, 0, sizeof(nladdr));
	nladdr.nl_family = AF_NETLINK;

	nlh.nlmsg_len = NLMSG_LENGTH(len);
	nlh.nlmsg_type = type;
	nlh.nlmsg_flags = NLM_F_ROOT|NLM_F_MATCH|NLM_F_REQUEST;
	nlh.nlmsg_pid = 0;
	nlh.nlmsg_seq = rth->dump = ++rth->seq;

	return sendmsg(rth->fd, &msg, 0);
}

static int rtnl_dump_filter(struct rtnl_handle *rth,
		int (*filter)(const struct sockaddr_nl *, struct nlmsghdr *n, void *),
		void *arg1/*,
		int (*junk)(struct sockaddr_nl *, struct nlmsghdr *n, void *),
		void *arg2*/)
{
	int retval = -1;
	char *buf = xmalloc(8*1024); /* avoid big stack buffer */
	struct sockaddr_nl nladdr;
	struct iovec iov = { buf, 8*1024 };

	while (1) {
		int status;
		struct nlmsghdr *h;

		struct msghdr msg = {
			(void*)&nladdr, sizeof(nladdr),
			&iov,	1,
			NULL,	0,
			0
		};

		status = recvmsg(rth->fd, &msg, 0);

		if (status < 0) {
			if (errno == EINTR)
				continue;
			bb_perror_msg("OVERRUN");
			continue;
		}
		if (status == 0) {
			bb_error_msg("EOF on netlink");
			goto ret;
		}
		if (msg.msg_namelen != sizeof(nladdr)) {
			bb_error_msg_and_die("sender address length == %d", msg.msg_namelen);
		}

		h = (struct nlmsghdr*)buf;
		while (NLMSG_OK(h, status)) {
			int err;

			if (nladdr.nl_pid != 0 ||
			    h->nlmsg_pid != rth->local.nl_pid ||
			    h->nlmsg_seq != rth->dump) {
//				if (junk) {
//					err = junk(&nladdr, h, arg2);
//					if (err < 0) {
//						retval = err;
//						goto ret;
//					}
//				}
				goto skip_it;
			}

			if (h->nlmsg_type == NLMSG_DONE) {
				goto ret_0;
			}
			if (h->nlmsg_type == NLMSG_ERROR) {
				struct nlmsgerr *l_err = (struct nlmsgerr*)NLMSG_DATA(h);
				if (h->nlmsg_len < NLMSG_LENGTH(sizeof(struct nlmsgerr))) {
					bb_error_msg("ERROR truncated");
				} else {
					errno = -l_err->error;
					bb_perror_msg("RTNETLINK answers");
				}
				goto ret;
			}
			err = filter(&nladdr, h, arg1);
			if (err < 0) {
				retval = err;
				goto ret;
			}

 skip_it:
			h = NLMSG_NEXT(h, status);
		}
		if (msg.msg_flags & MSG_TRUNC) {
			bb_error_msg("message truncated");
			continue;
		}
		if (status) {
			bb_error_msg_and_die("remnant of size %d!", status);
		}
	} /* while (1) */
 ret_0:
	retval++; /* = 0 */
 ret:
	free(buf);
	return retval;
}

int FAST_FUNC xrtnl_dump_filter(struct rtnl_handle *rth,
		int (*filter)(const struct sockaddr_nl *, struct nlmsghdr *, void *),
		void *arg1)
{
	int ret = rtnl_dump_filter(rth, filter, arg1/*, NULL, NULL*/);
	if (ret < 0)
		bb_error_msg_and_die("dump terminated");
	return ret;
}

int FAST_FUNC rtnl_talk(struct rtnl_handle *rtnl, struct nlmsghdr *n,
	      pid_t peer, unsigned groups,
	      struct nlmsghdr *answer,
	      int (*junk)(struct sockaddr_nl *, struct nlmsghdr *, void *),
	      void *jarg)
{
/* bbox doesn't use parameters no. 3, 4, 6, 7, they are stubbed out */
#define peer   0
#define groups 0
#define junk   NULL
#define jarg   NULL
	int retval = -1;
	int status;
	unsigned seq;
	struct nlmsghdr *h;
	struct sockaddr_nl nladdr;
	struct iovec iov = { (void*)n, n->nlmsg_len };
	char   *buf = xmalloc(8*1024); /* avoid big stack buffer */
	struct msghdr msg = {
		(void*)&nladdr, sizeof(nladdr),
		&iov,	1,
		NULL,	0,
		0
	};

	memset(&nladdr, 0, sizeof(nladdr));
	nladdr.nl_family = AF_NETLINK;
//	nladdr.nl_pid = peer;
//	nladdr.nl_groups = groups;

	n->nlmsg_seq = seq = ++rtnl->seq;
	if (answer == NULL) {
		n->nlmsg_flags |= NLM_F_ACK;
	}
	status = sendmsg(rtnl->fd, &msg, 0);

	if (status < 0) {
		bb_perror_msg("cannot talk to rtnetlink");
		goto ret;
	}

	iov.iov_base = buf;

	while (1) {
		iov.iov_len = 8*1024;
		status = recvmsg(rtnl->fd, &msg, 0);

		if (status < 0) {
			if (errno == EINTR) {
				continue;
			}
			bb_perror_msg("OVERRUN");
			continue;
		}
		if (status == 0) {
			bb_error_msg("EOF on netlink");
			goto ret;
		}
		if (msg.msg_namelen != sizeof(nladdr)) {
			bb_error_msg_and_die("sender address length == %d", msg.msg_namelen);
		}
		for (h = (struct nlmsghdr*)buf; status >= (int)sizeof(*h); ) {
//			int l_err;
			int len = h->nlmsg_len;
			int l = len - sizeof(*h);

			if (l < 0 || len > status) {
				if (msg.msg_flags & MSG_TRUNC) {
					bb_error_msg("truncated message");
					goto ret;
				}
				bb_error_msg_and_die("malformed message: len=%d!", len);
			}

			if (nladdr.nl_pid != peer ||
			    h->nlmsg_pid != rtnl->local.nl_pid ||
			    h->nlmsg_seq != seq) {
//				if (junk) {
//					l_err = junk(&nladdr, h, jarg);
//					if (l_err < 0) {
//						retval = l_err;
//						goto ret;
//					}
//				}
				continue;
			}

			if (h->nlmsg_type == NLMSG_ERROR) {
				struct nlmsgerr *err = (struct nlmsgerr*)NLMSG_DATA(h);
				if (l < (int)sizeof(struct nlmsgerr)) {
					bb_error_msg("ERROR truncated");
				} else {
					errno = - err->error;
					if (errno == 0) {
						if (answer) {
							memcpy(answer, h, h->nlmsg_len);
						}
						goto ret_0;
					}
					bb_perror_msg("RTNETLINK answers");
				}
				goto ret;
			}
			if (answer) {
				memcpy(answer, h, h->nlmsg_len);
				goto ret_0;
			}

			bb_error_msg("unexpected reply!");

			status -= NLMSG_ALIGN(len);
			h = (struct nlmsghdr*)((char*)h + NLMSG_ALIGN(len));
		}
		if (msg.msg_flags & MSG_TRUNC) {
			bb_error_msg("message truncated");
			continue;
		}
		if (status) {
			bb_error_msg_and_die("remnant of size %d!", status);
		}
	} /* while (1) */
 ret_0:
	retval++; /* = 0 */
 ret:
	free(buf);
	return retval;
}

int FAST_FUNC addattr32(struct nlmsghdr *n, int maxlen, int type, uint32_t data)
{
	int len = RTA_LENGTH(4);
	struct rtattr *rta;
	if ((int)(NLMSG_ALIGN(n->nlmsg_len) + len) > maxlen)
		return -1;
	rta = (struct rtattr*)(((char*)n) + NLMSG_ALIGN(n->nlmsg_len));
	rta->rta_type = type;
	rta->rta_len = len;
	memcpy(RTA_DATA(rta), &data, 4);
	n->nlmsg_len = NLMSG_ALIGN(n->nlmsg_len) + len;
	return 0;
}

int FAST_FUNC addattr_l(struct nlmsghdr *n, int maxlen, int type, void *data, int alen)
{
	int len = RTA_LENGTH(alen);
	struct rtattr *rta;

	if ((int)(NLMSG_ALIGN(n->nlmsg_len) + len) > maxlen)
		return -1;
	rta = (struct rtattr*)(((char*)n) + NLMSG_ALIGN(n->nlmsg_len));
	rta->rta_type = type;
	rta->rta_len = len;
	memcpy(RTA_DATA(rta), data, alen);
	n->nlmsg_len = NLMSG_ALIGN(n->nlmsg_len) + len;
	return 0;
}

int FAST_FUNC rta_addattr32(struct rtattr *rta, int maxlen, int type, uint32_t data)
{
	int len = RTA_LENGTH(4);
	struct rtattr *subrta;

	if (RTA_ALIGN(rta->rta_len) + len > maxlen) {
		return -1;
	}
	subrta = (struct rtattr*)(((char*)rta) + RTA_ALIGN(rta->rta_len));
	subrta->rta_type = type;
	subrta->rta_len = len;
	memcpy(RTA_DATA(subrta), &data, 4);
	rta->rta_len = NLMSG_ALIGN(rta->rta_len) + len;
	return 0;
}

int FAST_FUNC rta_addattr_l(struct rtattr *rta, int maxlen, int type, void *data, int alen)
{
	struct rtattr *subrta;
	int len = RTA_LENGTH(alen);

	if (RTA_ALIGN(rta->rta_len) + len > maxlen) {
		return -1;
	}
	subrta = (struct rtattr*)(((char*)rta) + RTA_ALIGN(rta->rta_len));
	subrta->rta_type = type;
	subrta->rta_len = len;
	memcpy(RTA_DATA(subrta), data, alen);
	rta->rta_len = NLMSG_ALIGN(rta->rta_len) + len;
	return 0;
}


int FAST_FUNC parse_rtattr(struct rtattr *tb[], int max, struct rtattr *rta, int len)
{
	while (RTA_OK(rta, len)) {
		if (rta->rta_type <= max) {
			tb[rta->rta_type] = rta;
		}
		rta = RTA_NEXT(rta,len);
	}
	if (len) {
		bb_error_msg("deficit %d, rta_len=%d!", len, rta->rta_len);
	}
	return 0;
}