blob: 7c80072eeb8b2b56933e56fa7750c67210ec026a
1 | /* vi: set sw=4 ts=4: */ |
2 | /* |
3 | * This program is free software; you can redistribute it and/or |
4 | * modify it under the terms of the GNU General Public License |
5 | * as published by the Free Software Foundation; either version |
6 | * 2 of the License, or (at your option) any later version. |
7 | * |
8 | * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> |
9 | */ |
10 | |
11 | #include <sys/socket.h> |
12 | #include <sys/uio.h> |
13 | |
14 | #include "libbb.h" |
15 | #include "libnetlink.h" |
16 | |
17 | void FAST_FUNC xrtnl_open(struct rtnl_handle *rth/*, unsigned subscriptions*/) |
18 | { |
19 | socklen_t addr_len; |
20 | |
21 | memset(rth, 0, sizeof(*rth)); |
22 | rth->fd = xsocket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE); |
23 | rth->local.nl_family = AF_NETLINK; |
24 | /*rth->local.nl_groups = subscriptions;*/ |
25 | |
26 | xbind(rth->fd, (struct sockaddr*)&rth->local, sizeof(rth->local)); |
27 | addr_len = sizeof(rth->local); |
28 | getsockname(rth->fd, (struct sockaddr*)&rth->local, &addr_len); |
29 | |
30 | /* too much paranoia |
31 | if (getsockname(rth->fd, (struct sockaddr*)&rth->local, &addr_len) < 0) |
32 | bb_perror_msg_and_die("getsockname"); |
33 | if (addr_len != sizeof(rth->local)) |
34 | bb_error_msg_and_die("wrong address length %d", addr_len); |
35 | if (rth->local.nl_family != AF_NETLINK) |
36 | bb_error_msg_and_die("wrong address family %d", rth->local.nl_family); |
37 | */ |
38 | rth->seq = time(NULL); |
39 | } |
40 | |
41 | int FAST_FUNC xrtnl_wilddump_request(struct rtnl_handle *rth, int family, int type) |
42 | { |
43 | struct { |
44 | struct nlmsghdr nlh; |
45 | struct rtgenmsg g; |
46 | } req; |
47 | |
48 | req.nlh.nlmsg_len = sizeof(req); |
49 | req.nlh.nlmsg_type = type; |
50 | req.nlh.nlmsg_flags = NLM_F_ROOT|NLM_F_MATCH|NLM_F_REQUEST; |
51 | req.nlh.nlmsg_pid = 0; |
52 | req.nlh.nlmsg_seq = rth->dump = ++rth->seq; |
53 | req.g.rtgen_family = family; |
54 | |
55 | return rtnl_send(rth, (void*)&req, sizeof(req)); |
56 | } |
57 | |
58 | //TODO: pass rth->fd instead of full rth? |
59 | int FAST_FUNC rtnl_send(struct rtnl_handle *rth, char *buf, int len) |
60 | { |
61 | struct sockaddr_nl nladdr; |
62 | |
63 | memset(&nladdr, 0, sizeof(nladdr)); |
64 | nladdr.nl_family = AF_NETLINK; |
65 | |
66 | return xsendto(rth->fd, buf, len, (struct sockaddr*)&nladdr, sizeof(nladdr)); |
67 | } |
68 | |
69 | int FAST_FUNC rtnl_dump_request(struct rtnl_handle *rth, int type, void *req, int len) |
70 | { |
71 | struct nlmsghdr nlh; |
72 | struct sockaddr_nl nladdr; |
73 | struct iovec iov[2] = { { &nlh, sizeof(nlh) }, { req, len } }; |
74 | struct msghdr msg = { |
75 | (void*)&nladdr, sizeof(nladdr), |
76 | iov, 2, |
77 | NULL, 0, |
78 | 0 |
79 | }; |
80 | |
81 | memset(&nladdr, 0, sizeof(nladdr)); |
82 | nladdr.nl_family = AF_NETLINK; |
83 | |
84 | nlh.nlmsg_len = NLMSG_LENGTH(len); |
85 | nlh.nlmsg_type = type; |
86 | nlh.nlmsg_flags = NLM_F_ROOT|NLM_F_MATCH|NLM_F_REQUEST; |
87 | nlh.nlmsg_pid = 0; |
88 | nlh.nlmsg_seq = rth->dump = ++rth->seq; |
89 | |
90 | return sendmsg(rth->fd, &msg, 0); |
91 | } |
92 | |
93 | static int rtnl_dump_filter(struct rtnl_handle *rth, |
94 | int (*filter)(const struct sockaddr_nl *, struct nlmsghdr *n, void *) FAST_FUNC, |
95 | void *arg1/*, |
96 | int (*junk)(struct sockaddr_nl *, struct nlmsghdr *n, void *), |
97 | void *arg2*/) |
98 | { |
99 | int retval = -1; |
100 | char *buf = xmalloc(8*1024); /* avoid big stack buffer */ |
101 | struct sockaddr_nl nladdr; |
102 | struct iovec iov = { buf, 8*1024 }; |
103 | |
104 | while (1) { |
105 | int status; |
106 | struct nlmsghdr *h; |
107 | |
108 | struct msghdr msg = { |
109 | (void*)&nladdr, sizeof(nladdr), |
110 | &iov, 1, |
111 | NULL, 0, |
112 | 0 |
113 | }; |
114 | |
115 | status = recvmsg(rth->fd, &msg, 0); |
116 | |
117 | if (status < 0) { |
118 | if (errno == EINTR) |
119 | continue; |
120 | bb_perror_msg("OVERRUN"); |
121 | continue; |
122 | } |
123 | if (status == 0) { |
124 | bb_error_msg("EOF on netlink"); |
125 | goto ret; |
126 | } |
127 | if (msg.msg_namelen != sizeof(nladdr)) { |
128 | bb_error_msg_and_die("sender address length == %d", msg.msg_namelen); |
129 | } |
130 | |
131 | h = (struct nlmsghdr*)buf; |
132 | while (NLMSG_OK(h, (unsigned) status)) { |
133 | int err; |
134 | |
135 | if (nladdr.nl_pid != 0 || |
136 | h->nlmsg_pid != rth->local.nl_pid || |
137 | h->nlmsg_seq != rth->dump |
138 | ) { |
139 | // if (junk) { |
140 | // err = junk(&nladdr, h, arg2); |
141 | // if (err < 0) { |
142 | // retval = err; |
143 | // goto ret; |
144 | // } |
145 | // } |
146 | goto skip_it; |
147 | } |
148 | |
149 | if (h->nlmsg_type == NLMSG_DONE) { |
150 | goto ret_0; |
151 | } |
152 | if (h->nlmsg_type == NLMSG_ERROR) { |
153 | struct nlmsgerr *l_err = (struct nlmsgerr*)NLMSG_DATA(h); |
154 | if (h->nlmsg_len < NLMSG_LENGTH(sizeof(struct nlmsgerr))) { |
155 | bb_error_msg("ERROR truncated"); |
156 | } else { |
157 | errno = -l_err->error; |
158 | bb_perror_msg("RTNETLINK answers"); |
159 | } |
160 | goto ret; |
161 | } |
162 | err = filter(&nladdr, h, arg1); |
163 | if (err < 0) { |
164 | retval = err; |
165 | goto ret; |
166 | } |
167 | |
168 | skip_it: |
169 | h = NLMSG_NEXT(h, status); |
170 | } |
171 | if (msg.msg_flags & MSG_TRUNC) { |
172 | bb_error_msg("message truncated"); |
173 | continue; |
174 | } |
175 | if (status) { |
176 | bb_error_msg_and_die("remnant of size %d!", status); |
177 | } |
178 | } /* while (1) */ |
179 | ret_0: |
180 | retval++; /* = 0 */ |
181 | ret: |
182 | free(buf); |
183 | return retval; |
184 | } |
185 | |
186 | int FAST_FUNC xrtnl_dump_filter(struct rtnl_handle *rth, |
187 | int (*filter)(const struct sockaddr_nl *, struct nlmsghdr *, void *) FAST_FUNC, |
188 | void *arg1) |
189 | { |
190 | int ret = rtnl_dump_filter(rth, filter, arg1/*, NULL, NULL*/); |
191 | if (ret < 0) |
192 | bb_error_msg_and_die("dump terminated"); |
193 | return ret; |
194 | } |
195 | |
196 | int FAST_FUNC rtnl_talk(struct rtnl_handle *rtnl, struct nlmsghdr *n, |
197 | pid_t peer, unsigned groups, |
198 | struct nlmsghdr *answer, |
199 | int (*junk)(struct sockaddr_nl *, struct nlmsghdr *, void *), |
200 | void *jarg) |
201 | { |
202 | /* bbox doesn't use parameters no. 3, 4, 6, 7, they are stubbed out */ |
203 | #define peer 0 |
204 | #define groups 0 |
205 | #define junk NULL |
206 | #define jarg NULL |
207 | int retval = -1; |
208 | int status; |
209 | unsigned seq; |
210 | struct nlmsghdr *h; |
211 | struct sockaddr_nl nladdr; |
212 | struct iovec iov = { (void*)n, n->nlmsg_len }; |
213 | char *buf = xmalloc(8*1024); /* avoid big stack buffer */ |
214 | struct msghdr msg = { |
215 | (void*)&nladdr, sizeof(nladdr), |
216 | &iov, 1, |
217 | NULL, 0, |
218 | 0 |
219 | }; |
220 | |
221 | memset(&nladdr, 0, sizeof(nladdr)); |
222 | nladdr.nl_family = AF_NETLINK; |
223 | // nladdr.nl_pid = peer; |
224 | // nladdr.nl_groups = groups; |
225 | |
226 | n->nlmsg_seq = seq = ++rtnl->seq; |
227 | if (answer == NULL) { |
228 | n->nlmsg_flags |= NLM_F_ACK; |
229 | } |
230 | status = sendmsg(rtnl->fd, &msg, 0); |
231 | |
232 | if (status < 0) { |
233 | bb_perror_msg("can't talk to rtnetlink"); |
234 | goto ret; |
235 | } |
236 | |
237 | iov.iov_base = buf; |
238 | |
239 | while (1) { |
240 | iov.iov_len = 8*1024; |
241 | status = recvmsg(rtnl->fd, &msg, 0); |
242 | |
243 | if (status < 0) { |
244 | if (errno == EINTR) { |
245 | continue; |
246 | } |
247 | bb_perror_msg("OVERRUN"); |
248 | continue; |
249 | } |
250 | if (status == 0) { |
251 | bb_error_msg("EOF on netlink"); |
252 | goto ret; |
253 | } |
254 | if (msg.msg_namelen != sizeof(nladdr)) { |
255 | bb_error_msg_and_die("sender address length == %d", msg.msg_namelen); |
256 | } |
257 | for (h = (struct nlmsghdr*)buf; status >= (int)sizeof(*h); ) { |
258 | // int l_err; |
259 | int len = h->nlmsg_len; |
260 | int l = len - sizeof(*h); |
261 | |
262 | if (l < 0 || len > status) { |
263 | if (msg.msg_flags & MSG_TRUNC) { |
264 | bb_error_msg("truncated message"); |
265 | goto ret; |
266 | } |
267 | bb_error_msg_and_die("malformed message: len=%d!", len); |
268 | } |
269 | |
270 | if (nladdr.nl_pid != peer || |
271 | h->nlmsg_pid != rtnl->local.nl_pid || |
272 | h->nlmsg_seq != seq |
273 | ) { |
274 | // if (junk) { |
275 | // l_err = junk(&nladdr, h, jarg); |
276 | // if (l_err < 0) { |
277 | // retval = l_err; |
278 | // goto ret; |
279 | // } |
280 | // } |
281 | continue; |
282 | } |
283 | |
284 | if (h->nlmsg_type == NLMSG_ERROR) { |
285 | struct nlmsgerr *err = (struct nlmsgerr*)NLMSG_DATA(h); |
286 | if (l < (int)sizeof(struct nlmsgerr)) { |
287 | bb_error_msg("ERROR truncated"); |
288 | } else { |
289 | errno = - err->error; |
290 | if (errno == 0) { |
291 | if (answer) { |
292 | memcpy(answer, h, h->nlmsg_len); |
293 | } |
294 | goto ret_0; |
295 | } |
296 | bb_perror_msg("RTNETLINK answers"); |
297 | } |
298 | goto ret; |
299 | } |
300 | if (answer) { |
301 | memcpy(answer, h, h->nlmsg_len); |
302 | goto ret_0; |
303 | } |
304 | |
305 | bb_error_msg("unexpected reply!"); |
306 | |
307 | status -= NLMSG_ALIGN(len); |
308 | h = (struct nlmsghdr*)((char*)h + NLMSG_ALIGN(len)); |
309 | } |
310 | if (msg.msg_flags & MSG_TRUNC) { |
311 | bb_error_msg("message truncated"); |
312 | continue; |
313 | } |
314 | if (status) { |
315 | bb_error_msg_and_die("remnant of size %d!", status); |
316 | } |
317 | } /* while (1) */ |
318 | ret_0: |
319 | retval++; /* = 0 */ |
320 | ret: |
321 | free(buf); |
322 | return retval; |
323 | } |
324 | |
325 | int FAST_FUNC addattr32(struct nlmsghdr *n, int maxlen, int type, uint32_t data) |
326 | { |
327 | int len = RTA_LENGTH(4); |
328 | struct rtattr *rta; |
329 | |
330 | if ((int)(NLMSG_ALIGN(n->nlmsg_len) + len) > maxlen) { |
331 | return -1; |
332 | } |
333 | rta = (struct rtattr*)(((char*)n) + NLMSG_ALIGN(n->nlmsg_len)); |
334 | rta->rta_type = type; |
335 | rta->rta_len = len; |
336 | move_to_unaligned32(RTA_DATA(rta), data); |
337 | n->nlmsg_len = NLMSG_ALIGN(n->nlmsg_len) + len; |
338 | return 0; |
339 | } |
340 | |
341 | int FAST_FUNC addattr_l(struct nlmsghdr *n, int maxlen, int type, void *data, int alen) |
342 | { |
343 | int len = RTA_LENGTH(alen); |
344 | struct rtattr *rta; |
345 | |
346 | if ((int)(NLMSG_ALIGN(n->nlmsg_len) + len) > maxlen) { |
347 | return -1; |
348 | } |
349 | rta = (struct rtattr*)(((char*)n) + NLMSG_ALIGN(n->nlmsg_len)); |
350 | rta->rta_type = type; |
351 | rta->rta_len = len; |
352 | memcpy(RTA_DATA(rta), data, alen); |
353 | n->nlmsg_len = NLMSG_ALIGN(n->nlmsg_len) + len; |
354 | return 0; |
355 | } |
356 | |
357 | int FAST_FUNC rta_addattr32(struct rtattr *rta, int maxlen, int type, uint32_t data) |
358 | { |
359 | int len = RTA_LENGTH(4); |
360 | struct rtattr *subrta; |
361 | |
362 | if (RTA_ALIGN(rta->rta_len) + len > maxlen) { |
363 | return -1; |
364 | } |
365 | subrta = (struct rtattr*)(((char*)rta) + RTA_ALIGN(rta->rta_len)); |
366 | subrta->rta_type = type; |
367 | subrta->rta_len = len; |
368 | move_to_unaligned32(RTA_DATA(subrta), data); |
369 | rta->rta_len = NLMSG_ALIGN(rta->rta_len) + len; |
370 | return 0; |
371 | } |
372 | |
373 | int FAST_FUNC rta_addattr_l(struct rtattr *rta, int maxlen, int type, void *data, int alen) |
374 | { |
375 | struct rtattr *subrta; |
376 | int len = RTA_LENGTH(alen); |
377 | |
378 | if (RTA_ALIGN(rta->rta_len) + len > maxlen) { |
379 | return -1; |
380 | } |
381 | subrta = (struct rtattr*)(((char*)rta) + RTA_ALIGN(rta->rta_len)); |
382 | subrta->rta_type = type; |
383 | subrta->rta_len = len; |
384 | memcpy(RTA_DATA(subrta), data, alen); |
385 | rta->rta_len = NLMSG_ALIGN(rta->rta_len) + len; |
386 | return 0; |
387 | } |
388 | |
389 | |
390 | void FAST_FUNC parse_rtattr(struct rtattr *tb[], int max, struct rtattr *rta, int len) |
391 | { |
392 | while (RTA_OK(rta, len)) { |
393 | if (rta->rta_type <= max) { |
394 | tb[rta->rta_type] = rta; |
395 | } |
396 | rta = RTA_NEXT(rta, len); |
397 | } |
398 | if (len) { |
399 | bb_error_msg("deficit %d, rta_len=%d!", len, rta->rta_len); |
400 | } |
401 | } |
402 |