1/*
2 * libnetlink.c	RTnetlink service routines.
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 <net/if_arp.h>
19#include <sys/socket.h>
20#include <netinet/in.h>
21#include <string.h>
22#include <errno.h>
23#include <time.h>
24#include <sys/uio.h>
25
26#include "libnetlink.h"
27
28#ifndef SOL_NETLINK
29#define SOL_NETLINK 270
30#endif
31
32#ifndef MIN
33#define MIN(a, b) ((a) < (b) ? (a) : (b))
34#endif
35
36int rcvbuf = 1024 * 1024;
37
38void rtnl_close(struct rtnl_handle *rth)
39{
40	if (rth->fd >= 0) {
41		close(rth->fd);
42		rth->fd = -1;
43	}
44}
45
46int rtnl_open_byproto(struct rtnl_handle *rth, unsigned subscriptions,
47		      int protocol)
48{
49	socklen_t addr_len;
50	int sndbuf = 32768;
51
52	memset(rth, 0, sizeof(*rth));
53
54	rth->proto = protocol;
55	rth->fd = socket(AF_NETLINK, SOCK_RAW | SOCK_CLOEXEC, protocol);
56	if (rth->fd < 0) {
57		perror("Cannot open netlink socket");
58		return -1;
59	}
60
61	if (setsockopt(rth->fd,SOL_SOCKET,SO_SNDBUF,&sndbuf,sizeof(sndbuf)) < 0) {
62		perror("SO_SNDBUF");
63		return -1;
64	}
65
66	if (setsockopt(rth->fd,SOL_SOCKET,SO_RCVBUF,&rcvbuf,sizeof(rcvbuf)) < 0) {
67		perror("SO_RCVBUF");
68		return -1;
69	}
70
71	memset(&rth->local, 0, sizeof(rth->local));
72	rth->local.nl_family = AF_NETLINK;
73	rth->local.nl_groups = subscriptions;
74
75	if (bind(rth->fd, (struct sockaddr*)&rth->local, sizeof(rth->local)) < 0) {
76		perror("Cannot bind netlink socket");
77		return -1;
78	}
79	addr_len = sizeof(rth->local);
80	if (getsockname(rth->fd, (struct sockaddr*)&rth->local, &addr_len) < 0) {
81		perror("Cannot getsockname");
82		return -1;
83	}
84	if (addr_len != sizeof(rth->local)) {
85		fprintf(stderr, "Wrong address length %d\n", addr_len);
86		return -1;
87	}
88	if (rth->local.nl_family != AF_NETLINK) {
89		fprintf(stderr, "Wrong address family %d\n", rth->local.nl_family);
90		return -1;
91	}
92	rth->seq = time(NULL);
93	return 0;
94}
95
96int rtnl_open(struct rtnl_handle *rth, unsigned subscriptions)
97{
98	return rtnl_open_byproto(rth, subscriptions, NETLINK_ROUTE);
99}
100
101int rtnl_wilddump_request(struct rtnl_handle *rth, int family, int type)
102{
103	return rtnl_wilddump_req_filter(rth, family, type, RTEXT_FILTER_VF);
104}
105
106int rtnl_wilddump_req_filter(struct rtnl_handle *rth, int family, int type,
107			    __u32 filt_mask)
108{
109	struct {
110		struct nlmsghdr nlh;
111		struct ifinfomsg ifm;
112		/* attribute has to be NLMSG aligned */
113		struct rtattr ext_req __attribute__ ((aligned(NLMSG_ALIGNTO)));
114		__u32 ext_filter_mask;
115	} req;
116
117	memset(&req, 0, sizeof(req));
118	req.nlh.nlmsg_len = sizeof(req);
119	req.nlh.nlmsg_type = type;
120	req.nlh.nlmsg_flags = NLM_F_DUMP|NLM_F_REQUEST;
121	req.nlh.nlmsg_pid = 0;
122	req.nlh.nlmsg_seq = rth->dump = ++rth->seq;
123	req.ifm.ifi_family = family;
124
125	req.ext_req.rta_type = IFLA_EXT_MASK;
126	req.ext_req.rta_len = RTA_LENGTH(sizeof(__u32));
127	req.ext_filter_mask = filt_mask;
128
129	return send(rth->fd, (void*)&req, sizeof(req), 0);
130}
131
132int rtnl_send(struct rtnl_handle *rth, const void *buf, int len)
133{
134	return send(rth->fd, buf, len, 0);
135}
136
137int rtnl_send_check(struct rtnl_handle *rth, const void *buf, int len)
138{
139	struct nlmsghdr *h;
140	int status;
141	char resp[1024];
142
143	status = send(rth->fd, buf, len, 0);
144	if (status < 0)
145		return status;
146
147	/* Check for immediate errors */
148	status = recv(rth->fd, resp, sizeof(resp), MSG_DONTWAIT|MSG_PEEK);
149	if (status < 0) {
150		if (errno == EAGAIN)
151			return 0;
152		return -1;
153	}
154
155	for (h = (struct nlmsghdr *)resp; NLMSG_OK(h, status);
156	     h = NLMSG_NEXT(h, status)) {
157		if (h->nlmsg_type == NLMSG_ERROR) {
158			struct nlmsgerr *err = (struct nlmsgerr*)NLMSG_DATA(h);
159			if (h->nlmsg_len < NLMSG_LENGTH(sizeof(struct nlmsgerr)))
160				fprintf(stderr, "ERROR truncated\n");
161			else
162				errno = -err->error;
163			return -1;
164		}
165	}
166
167	return 0;
168}
169
170int rtnl_dump_request(struct rtnl_handle *rth, int type, void *req, int len)
171{
172	struct nlmsghdr nlh;
173	struct sockaddr_nl nladdr = { .nl_family = AF_NETLINK };
174	struct iovec iov[2] = {
175		{ .iov_base = &nlh, .iov_len = sizeof(nlh) },
176		{ .iov_base = req, .iov_len = len }
177	};
178	struct msghdr msg = {
179		.msg_name = &nladdr,
180		.msg_namelen = 	sizeof(nladdr),
181		.msg_iov = iov,
182		.msg_iovlen = 2,
183	};
184
185	nlh.nlmsg_len = NLMSG_LENGTH(len);
186	nlh.nlmsg_type = type;
187	nlh.nlmsg_flags = NLM_F_DUMP|NLM_F_REQUEST;
188	nlh.nlmsg_pid = 0;
189	nlh.nlmsg_seq = rth->dump = ++rth->seq;
190
191	return sendmsg(rth->fd, &msg, 0);
192}
193
194int rtnl_dump_request_n(struct rtnl_handle *rth, struct nlmsghdr *n)
195{
196	struct sockaddr_nl nladdr = { .nl_family = AF_NETLINK };
197	struct iovec iov = {
198		.iov_base = (void*) n,
199		.iov_len = n->nlmsg_len
200	};
201	struct msghdr msg = {
202		.msg_name = &nladdr,
203		.msg_namelen = sizeof(nladdr),
204		.msg_iov = &iov,
205		.msg_iovlen = 1,
206	};
207
208	n->nlmsg_flags = NLM_F_DUMP|NLM_F_REQUEST;
209	n->nlmsg_pid = 0;
210	n->nlmsg_seq = rth->dump = ++rth->seq;
211
212	return sendmsg(rth->fd, &msg, 0);
213}
214
215int rtnl_dump_filter_l(struct rtnl_handle *rth,
216		       const struct rtnl_dump_filter_arg *arg)
217{
218	struct sockaddr_nl nladdr;
219	struct iovec iov;
220	struct msghdr msg = {
221		.msg_name = &nladdr,
222		.msg_namelen = sizeof(nladdr),
223		.msg_iov = &iov,
224		.msg_iovlen = 1,
225	};
226	char buf[16384];
227	int dump_intr = 0;
228
229	iov.iov_base = buf;
230	while (1) {
231		int status;
232		const struct rtnl_dump_filter_arg *a;
233		int found_done = 0;
234		int msglen = 0;
235
236		iov.iov_len = sizeof(buf);
237		status = recvmsg(rth->fd, &msg, 0);
238
239		if (status < 0) {
240			if (errno == EINTR || errno == EAGAIN)
241				continue;
242			fprintf(stderr, "netlink receive error %s (%d)\n",
243				strerror(errno), errno);
244			return -1;
245		}
246
247		if (status == 0) {
248			fprintf(stderr, "EOF on netlink\n");
249			return -1;
250		}
251
252		if (rth->dump_fp)
253			fwrite(buf, 1, NLMSG_ALIGN(status), rth->dump_fp);
254
255		for (a = arg; a->filter; a++) {
256			struct nlmsghdr *h = (struct nlmsghdr*)buf;
257			msglen = status;
258
259			while (NLMSG_OK(h, msglen)) {
260				int err = 0;
261
262				h->nlmsg_flags &= ~a->nc_flags;
263
264				if (nladdr.nl_pid != 0 ||
265				    h->nlmsg_pid != rth->local.nl_pid ||
266				    h->nlmsg_seq != rth->dump)
267					goto skip_it;
268
269				if (h->nlmsg_flags & NLM_F_DUMP_INTR)
270					dump_intr = 1;
271
272				if (h->nlmsg_type == NLMSG_DONE) {
273					found_done = 1;
274					break; /* process next filter */
275				}
276				if (h->nlmsg_type == NLMSG_ERROR) {
277					struct nlmsgerr *err = (struct nlmsgerr*)NLMSG_DATA(h);
278					if (h->nlmsg_len < NLMSG_LENGTH(sizeof(struct nlmsgerr))) {
279						fprintf(stderr,
280							"ERROR truncated\n");
281					} else {
282						errno = -err->error;
283						if (rth->proto == NETLINK_SOCK_DIAG &&
284						    (errno == ENOENT ||
285						     errno == EOPNOTSUPP))
286							return -1;
287
288						perror("RTNETLINK answers");
289					}
290					return -1;
291				}
292
293				if (!rth->dump_fp) {
294					err = a->filter(&nladdr, h, a->arg1);
295					if (err < 0)
296						return err;
297				}
298
299skip_it:
300				h = NLMSG_NEXT(h, msglen);
301			}
302		}
303
304		if (found_done) {
305			if (dump_intr)
306				fprintf(stderr,
307					"Dump was interrupted and may be inconsistent.\n");
308			return 0;
309		}
310
311		if (msg.msg_flags & MSG_TRUNC) {
312			fprintf(stderr, "Message truncated\n");
313			continue;
314		}
315		if (msglen) {
316			fprintf(stderr, "!!!Remnant of size %d\n", msglen);
317			exit(1);
318		}
319	}
320}
321
322int rtnl_dump_filter_nc(struct rtnl_handle *rth,
323		     rtnl_filter_t filter,
324		     void *arg1, __u16 nc_flags)
325{
326	const struct rtnl_dump_filter_arg a[2] = {
327		{ .filter = filter, .arg1 = arg1, .nc_flags = nc_flags, },
328		{ .filter = NULL,   .arg1 = NULL, .nc_flags = 0, },
329	};
330
331	return rtnl_dump_filter_l(rth, a);
332}
333
334int rtnl_talk(struct rtnl_handle *rtnl, struct nlmsghdr *n,
335	      struct nlmsghdr *answer, size_t maxlen)
336{
337	int status;
338	unsigned seq;
339	struct nlmsghdr *h;
340	struct sockaddr_nl nladdr;
341	struct iovec iov = {
342		.iov_base = (void*) n,
343		.iov_len = n->nlmsg_len
344	};
345	struct msghdr msg = {
346		.msg_name = &nladdr,
347		.msg_namelen = sizeof(nladdr),
348		.msg_iov = &iov,
349		.msg_iovlen = 1,
350	};
351	char   buf[32768];
352
353	memset(&nladdr, 0, sizeof(nladdr));
354	nladdr.nl_family = AF_NETLINK;
355
356	n->nlmsg_seq = seq = ++rtnl->seq;
357
358	if (answer == NULL)
359		n->nlmsg_flags |= NLM_F_ACK;
360
361	status = sendmsg(rtnl->fd, &msg, 0);
362	if (status < 0) {
363		perror("Cannot talk to rtnetlink");
364		return -1;
365	}
366
367	memset(buf,0,sizeof(buf));
368
369	iov.iov_base = buf;
370	while (1) {
371		iov.iov_len = sizeof(buf);
372		status = recvmsg(rtnl->fd, &msg, 0);
373
374		if (status < 0) {
375			if (errno == EINTR || errno == EAGAIN)
376				continue;
377			fprintf(stderr, "netlink receive error %s (%d)\n",
378				strerror(errno), errno);
379			return -1;
380		}
381		if (status == 0) {
382			fprintf(stderr, "EOF on netlink\n");
383			return -1;
384		}
385		if (msg.msg_namelen != sizeof(nladdr)) {
386			fprintf(stderr, "sender address length == %d\n", msg.msg_namelen);
387			exit(1);
388		}
389		for (h = (struct nlmsghdr*)buf; status >= sizeof(*h); ) {
390			int len = h->nlmsg_len;
391			int l = len - sizeof(*h);
392
393			if (l < 0 || len>status) {
394				if (msg.msg_flags & MSG_TRUNC) {
395					fprintf(stderr, "Truncated message\n");
396					return -1;
397				}
398				fprintf(stderr, "!!!malformed message: len=%d\n", len);
399				exit(1);
400			}
401
402			if (nladdr.nl_pid != 0 ||
403			    h->nlmsg_pid != rtnl->local.nl_pid ||
404			    h->nlmsg_seq != seq) {
405				/* Don't forget to skip that message. */
406				status -= NLMSG_ALIGN(len);
407				h = (struct nlmsghdr*)((char*)h + NLMSG_ALIGN(len));
408				continue;
409			}
410
411			if (h->nlmsg_type == NLMSG_ERROR) {
412				struct nlmsgerr *err = (struct nlmsgerr*)NLMSG_DATA(h);
413				if (l < sizeof(struct nlmsgerr)) {
414					fprintf(stderr, "ERROR truncated\n");
415				} else if (!err->error) {
416					if (answer)
417						memcpy(answer, h,
418						       MIN(maxlen, h->nlmsg_len));
419					return 0;
420				}
421
422				if (rtnl->proto != NETLINK_SOCK_DIAG)
423					fprintf(stderr,
424						"RTNETLINK answers: %s\n",
425						strerror(-err->error));
426				errno = -err->error;
427				return -1;
428			}
429
430			if (answer) {
431				memcpy(answer, h,
432				       MIN(maxlen, h->nlmsg_len));
433				return 0;
434			}
435
436			fprintf(stderr, "Unexpected reply!!!\n");
437
438			status -= NLMSG_ALIGN(len);
439			h = (struct nlmsghdr*)((char*)h + NLMSG_ALIGN(len));
440		}
441
442		if (msg.msg_flags & MSG_TRUNC) {
443			fprintf(stderr, "Message truncated\n");
444			continue;
445		}
446
447		if (status) {
448			fprintf(stderr, "!!!Remnant of size %d\n", status);
449			exit(1);
450		}
451	}
452}
453
454int rtnl_listen_all_nsid(struct rtnl_handle *rth)
455{
456	unsigned int on = 1;
457
458	if (setsockopt(rth->fd, SOL_NETLINK, NETLINK_LISTEN_ALL_NSID, &on,
459		       sizeof(on)) < 0) {
460		perror("NETLINK_LISTEN_ALL_NSID");
461		return -1;
462	}
463	rth->flags |= RTNL_HANDLE_F_LISTEN_ALL_NSID;
464	return 0;
465}
466
467int rtnl_listen(struct rtnl_handle *rtnl,
468		rtnl_listen_filter_t handler,
469		void *jarg)
470{
471	int status;
472	struct nlmsghdr *h;
473	struct sockaddr_nl nladdr;
474	struct iovec iov;
475	struct msghdr msg = {
476		.msg_name = &nladdr,
477		.msg_namelen = sizeof(nladdr),
478		.msg_iov = &iov,
479		.msg_iovlen = 1,
480	};
481	char   buf[16384];
482	char   cmsgbuf[BUFSIZ];
483
484	if (rtnl->flags & RTNL_HANDLE_F_LISTEN_ALL_NSID) {
485		msg.msg_control = &cmsgbuf;
486		msg.msg_controllen = sizeof(cmsgbuf);
487	}
488
489	memset(&nladdr, 0, sizeof(nladdr));
490	nladdr.nl_family = AF_NETLINK;
491	nladdr.nl_pid = 0;
492	nladdr.nl_groups = 0;
493
494	iov.iov_base = buf;
495	while (1) {
496		struct rtnl_ctrl_data ctrl;
497		struct cmsghdr *cmsg;
498
499		iov.iov_len = sizeof(buf);
500		status = recvmsg(rtnl->fd, &msg, 0);
501
502		if (status < 0) {
503			if (errno == EINTR || errno == EAGAIN)
504				continue;
505			fprintf(stderr, "netlink receive error %s (%d)\n",
506				strerror(errno), errno);
507			if (errno == ENOBUFS)
508				continue;
509			return -1;
510		}
511		if (status == 0) {
512			fprintf(stderr, "EOF on netlink\n");
513			return -1;
514		}
515		if (msg.msg_namelen != sizeof(nladdr)) {
516			fprintf(stderr, "Sender address length == %d\n", msg.msg_namelen);
517			exit(1);
518		}
519
520		if (rtnl->flags & RTNL_HANDLE_F_LISTEN_ALL_NSID) {
521			memset(&ctrl, 0, sizeof(ctrl));
522			ctrl.nsid = -1;
523			for (cmsg = CMSG_FIRSTHDR(&msg); cmsg;
524			     cmsg = CMSG_NXTHDR(&msg, cmsg))
525				if (cmsg->cmsg_level == SOL_NETLINK &&
526				    cmsg->cmsg_type == NETLINK_LISTEN_ALL_NSID &&
527				    cmsg->cmsg_len == CMSG_LEN(sizeof(int))) {
528					int *data = (int *)CMSG_DATA(cmsg);
529
530					ctrl.nsid = *data;
531				}
532		}
533
534		for (h = (struct nlmsghdr*)buf; status >= sizeof(*h); ) {
535			int err;
536			int len = h->nlmsg_len;
537			int l = len - sizeof(*h);
538
539			if (l<0 || len>status) {
540				if (msg.msg_flags & MSG_TRUNC) {
541					fprintf(stderr, "Truncated message\n");
542					return -1;
543				}
544				fprintf(stderr, "!!!malformed message: len=%d\n", len);
545				exit(1);
546			}
547
548			err = handler(&nladdr, &ctrl, h, jarg);
549			if (err < 0)
550				return err;
551
552			status -= NLMSG_ALIGN(len);
553			h = (struct nlmsghdr*)((char*)h + NLMSG_ALIGN(len));
554		}
555		if (msg.msg_flags & MSG_TRUNC) {
556			fprintf(stderr, "Message truncated\n");
557			continue;
558		}
559		if (status) {
560			fprintf(stderr, "!!!Remnant of size %d\n", status);
561			exit(1);
562		}
563	}
564}
565
566int rtnl_from_file(FILE *rtnl, rtnl_listen_filter_t handler,
567		   void *jarg)
568{
569	int status;
570	struct sockaddr_nl nladdr;
571	char   buf[16384];
572	struct nlmsghdr *h = (void*)buf;
573
574	memset(&nladdr, 0, sizeof(nladdr));
575	nladdr.nl_family = AF_NETLINK;
576	nladdr.nl_pid = 0;
577	nladdr.nl_groups = 0;
578
579	while (1) {
580		int err, len;
581		int l;
582
583		status = fread(&buf, 1, sizeof(*h), rtnl);
584
585		if (status < 0) {
586			if (errno == EINTR)
587				continue;
588			perror("rtnl_from_file: fread");
589			return -1;
590		}
591		if (status == 0)
592			return 0;
593
594		len = h->nlmsg_len;
595		l = len - sizeof(*h);
596
597		if (l<0 || len>sizeof(buf)) {
598			fprintf(stderr, "!!!malformed message: len=%d @%lu\n",
599				len, ftell(rtnl));
600			return -1;
601		}
602
603		status = fread(NLMSG_DATA(h), 1, NLMSG_ALIGN(l), rtnl);
604
605		if (status < 0) {
606			perror("rtnl_from_file: fread");
607			return -1;
608		}
609		if (status < l) {
610			fprintf(stderr, "rtnl-from_file: truncated message\n");
611			return -1;
612		}
613
614		err = handler(&nladdr, NULL, h, jarg);
615		if (err < 0)
616			return err;
617	}
618}
619
620int addattr(struct nlmsghdr *n, int maxlen, int type)
621{
622	return addattr_l(n, maxlen, type, NULL, 0);
623}
624
625int addattr8(struct nlmsghdr *n, int maxlen, int type, __u8 data)
626{
627	return addattr_l(n, maxlen, type, &data, sizeof(__u8));
628}
629
630int addattr16(struct nlmsghdr *n, int maxlen, int type, __u16 data)
631{
632	return addattr_l(n, maxlen, type, &data, sizeof(__u16));
633}
634
635int addattr32(struct nlmsghdr *n, int maxlen, int type, __u32 data)
636{
637	return addattr_l(n, maxlen, type, &data, sizeof(__u32));
638}
639
640int addattr64(struct nlmsghdr *n, int maxlen, int type, __u64 data)
641{
642	return addattr_l(n, maxlen, type, &data, sizeof(__u64));
643}
644
645int addattrstrz(struct nlmsghdr *n, int maxlen, int type, const char *str)
646{
647	return addattr_l(n, maxlen, type, str, strlen(str)+1);
648}
649
650int addattr_l(struct nlmsghdr *n, int maxlen, int type, const void *data,
651	      int alen)
652{
653	int len = RTA_LENGTH(alen);
654	struct rtattr *rta;
655
656	if (NLMSG_ALIGN(n->nlmsg_len) + RTA_ALIGN(len) > maxlen) {
657		fprintf(stderr, "addattr_l ERROR: message exceeded bound of %d\n",maxlen);
658		return -1;
659	}
660	rta = NLMSG_TAIL(n);
661	rta->rta_type = type;
662	rta->rta_len = len;
663	memcpy(RTA_DATA(rta), data, alen);
664	n->nlmsg_len = NLMSG_ALIGN(n->nlmsg_len) + RTA_ALIGN(len);
665	return 0;
666}
667
668int addraw_l(struct nlmsghdr *n, int maxlen, const void *data, int len)
669{
670	if (NLMSG_ALIGN(n->nlmsg_len) + NLMSG_ALIGN(len) > maxlen) {
671		fprintf(stderr, "addraw_l ERROR: message exceeded bound of %d\n",maxlen);
672		return -1;
673	}
674
675	memcpy(NLMSG_TAIL(n), data, len);
676	memset((void *) NLMSG_TAIL(n) + len, 0, NLMSG_ALIGN(len) - len);
677	n->nlmsg_len = NLMSG_ALIGN(n->nlmsg_len) + NLMSG_ALIGN(len);
678	return 0;
679}
680
681struct rtattr *addattr_nest(struct nlmsghdr *n, int maxlen, int type)
682{
683	struct rtattr *nest = NLMSG_TAIL(n);
684
685	addattr_l(n, maxlen, type, NULL, 0);
686	return nest;
687}
688
689int addattr_nest_end(struct nlmsghdr *n, struct rtattr *nest)
690{
691	nest->rta_len = (void *)NLMSG_TAIL(n) - (void *)nest;
692	return n->nlmsg_len;
693}
694
695struct rtattr *addattr_nest_compat(struct nlmsghdr *n, int maxlen, int type,
696				   const void *data, int len)
697{
698	struct rtattr *start = NLMSG_TAIL(n);
699
700	addattr_l(n, maxlen, type, data, len);
701	addattr_nest(n, maxlen, type);
702	return start;
703}
704
705int addattr_nest_compat_end(struct nlmsghdr *n, struct rtattr *start)
706{
707	struct rtattr *nest = (void *)start + NLMSG_ALIGN(start->rta_len);
708
709	start->rta_len = (void *)NLMSG_TAIL(n) - (void *)start;
710	addattr_nest_end(n, nest);
711	return n->nlmsg_len;
712}
713
714int rta_addattr32(struct rtattr *rta, int maxlen, int type, __u32 data)
715{
716	int len = RTA_LENGTH(4);
717	struct rtattr *subrta;
718
719	if (RTA_ALIGN(rta->rta_len) + len > maxlen) {
720		fprintf(stderr,"rta_addattr32: Error! max allowed bound %d exceeded\n",maxlen);
721		return -1;
722	}
723	subrta = (struct rtattr*)(((char*)rta) + RTA_ALIGN(rta->rta_len));
724	subrta->rta_type = type;
725	subrta->rta_len = len;
726	memcpy(RTA_DATA(subrta), &data, 4);
727	rta->rta_len = NLMSG_ALIGN(rta->rta_len) + len;
728	return 0;
729}
730
731int rta_addattr_l(struct rtattr *rta, int maxlen, int type,
732		  const void *data, int alen)
733{
734	struct rtattr *subrta;
735	int len = RTA_LENGTH(alen);
736
737	if (RTA_ALIGN(rta->rta_len) + RTA_ALIGN(len) > maxlen) {
738		fprintf(stderr,"rta_addattr_l: Error! max allowed bound %d exceeded\n",maxlen);
739		return -1;
740	}
741	subrta = (struct rtattr*)(((char*)rta) + RTA_ALIGN(rta->rta_len));
742	subrta->rta_type = type;
743	subrta->rta_len = len;
744	memcpy(RTA_DATA(subrta), data, alen);
745	rta->rta_len = NLMSG_ALIGN(rta->rta_len) + RTA_ALIGN(len);
746	return 0;
747}
748
749int rta_addattr8(struct rtattr *rta, int maxlen, int type, __u8 data)
750{
751	return rta_addattr_l(rta, maxlen, type, &data, sizeof(__u8));
752}
753
754int rta_addattr16(struct rtattr *rta, int maxlen, int type, __u16 data)
755{
756	return rta_addattr_l(rta, maxlen, type, &data, sizeof(__u16));
757}
758
759int rta_addattr64(struct rtattr *rta, int maxlen, int type, __u64 data)
760{
761	return rta_addattr_l(rta, maxlen, type, &data, sizeof(__u64));
762}
763
764struct rtattr *rta_nest(struct rtattr *rta, int maxlen, int type)
765{
766	struct rtattr *nest = RTA_TAIL(rta);
767
768	rta_addattr_l(rta, maxlen, type, NULL, 0);
769
770	return nest;
771}
772
773int rta_nest_end(struct rtattr *rta, struct rtattr *nest)
774{
775	nest->rta_len = (void *)RTA_TAIL(rta) - (void *)nest;
776
777	return rta->rta_len;
778}
779
780int parse_rtattr(struct rtattr *tb[], int max, struct rtattr *rta, int len)
781{
782	return parse_rtattr_flags(tb, max, rta, len, 0);
783}
784
785int parse_rtattr_flags(struct rtattr *tb[], int max, struct rtattr *rta,
786		       int len, unsigned short flags)
787{
788	unsigned short type;
789
790	memset(tb, 0, sizeof(struct rtattr *) * (max + 1));
791	while (RTA_OK(rta, len)) {
792		type = rta->rta_type & ~flags;
793		if ((type <= max) && (!tb[type]))
794			tb[type] = rta;
795		rta = RTA_NEXT(rta,len);
796	}
797	if (len)
798		fprintf(stderr, "!!!Deficit %d, rta_len=%d\n", len, rta->rta_len);
799	return 0;
800}
801
802int parse_rtattr_byindex(struct rtattr *tb[], int max, struct rtattr *rta, int len)
803{
804	int i = 0;
805
806	memset(tb, 0, sizeof(struct rtattr *) * max);
807	while (RTA_OK(rta, len)) {
808		if (rta->rta_type <= max && i < max)
809			tb[i++] = rta;
810		rta = RTA_NEXT(rta,len);
811	}
812	if (len)
813		fprintf(stderr, "!!!Deficit %d, rta_len=%d\n", len, rta->rta_len);
814	return i;
815}
816
817struct rtattr *parse_rtattr_one(int type, struct rtattr *rta, int len)
818{
819	while (RTA_OK(rta, len)) {
820		if (rta->rta_type == type)
821			return rta;
822		rta = RTA_NEXT(rta, len);
823	}
824	if (len)
825		fprintf(stderr, "!!!Deficit %d, rta_len=%d\n", len, rta->rta_len);
826	return NULL;
827}
828
829int __parse_rtattr_nested_compat(struct rtattr *tb[], int max, struct rtattr *rta,
830			         int len)
831{
832	if (RTA_PAYLOAD(rta) < len)
833		return -1;
834	if (RTA_PAYLOAD(rta) >= RTA_ALIGN(len) + sizeof(struct rtattr)) {
835		rta = RTA_DATA(rta) + RTA_ALIGN(len);
836		return parse_rtattr_nested(tb, max, rta);
837	}
838	memset(tb, 0, sizeof(struct rtattr *) * (max + 1));
839	return 0;
840}
841