1 | /* getifaddrs -- get names and addresses of all network interfaces |
2 | Copyright (C) 2003-2016 Free Software Foundation, Inc. |
3 | This file is part of the GNU C Library. |
4 | |
5 | The GNU C Library is free software; you can redistribute it and/or |
6 | modify it under the terms of the GNU Lesser General Public |
7 | License as published by the Free Software Foundation; either |
8 | version 2.1 of the License, or (at your option) any later version. |
9 | |
10 | The GNU C Library is distributed in the hope that it will be useful, |
11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
13 | Lesser General Public License for more details. |
14 | |
15 | You should have received a copy of the GNU Lesser General Public |
16 | License along with the GNU C Library; if not, see |
17 | <http://www.gnu.org/licenses/>. */ |
18 | |
19 | #include <alloca.h> |
20 | #include <assert.h> |
21 | #include <errno.h> |
22 | #include <ifaddrs.h> |
23 | #include <net/if.h> |
24 | #include <netinet/in.h> |
25 | #include <netpacket/packet.h> |
26 | #include <stdbool.h> |
27 | #include <stdint.h> |
28 | #include <stdlib.h> |
29 | #include <string.h> |
30 | #include <sys/ioctl.h> |
31 | #include <sys/socket.h> |
32 | #include <sysdep.h> |
33 | #include <time.h> |
34 | #include <unistd.h> |
35 | |
36 | #include "netlinkaccess.h" |
37 | |
38 | |
39 | /* There is a problem with this type. The address length for |
40 | Infiniband sockets is much longer than the 8 bytes allocated in the |
41 | sockaddr_ll definition. Hence we use here a special |
42 | definition. */ |
43 | struct sockaddr_ll_max |
44 | { |
45 | unsigned short int sll_family; |
46 | unsigned short int sll_protocol; |
47 | int sll_ifindex; |
48 | unsigned short int sll_hatype; |
49 | unsigned char sll_pkttype; |
50 | unsigned char sll_halen; |
51 | unsigned char sll_addr[24]; |
52 | }; |
53 | |
54 | |
55 | /* struct to hold the data for one ifaddrs entry, so we can allocate |
56 | everything at once. */ |
57 | struct ifaddrs_storage |
58 | { |
59 | struct ifaddrs ifa; |
60 | union |
61 | { |
62 | /* Save space for the biggest of the four used sockaddr types and |
63 | avoid a lot of casts. */ |
64 | struct sockaddr sa; |
65 | struct sockaddr_ll_max sl; |
66 | struct sockaddr_in s4; |
67 | struct sockaddr_in6 s6; |
68 | } addr, netmask, broadaddr; |
69 | char name[IF_NAMESIZE + 1]; |
70 | }; |
71 | |
72 | |
73 | void |
74 | __netlink_free_handle (struct netlink_handle *h) |
75 | { |
76 | struct netlink_res *ptr; |
77 | int saved_errno = errno; |
78 | |
79 | ptr = h->nlm_list; |
80 | while (ptr != NULL) |
81 | { |
82 | struct netlink_res *tmpptr; |
83 | |
84 | tmpptr = ptr->next; |
85 | free (ptr); |
86 | ptr = tmpptr; |
87 | } |
88 | |
89 | __set_errno (saved_errno); |
90 | } |
91 | |
92 | |
93 | static int |
94 | __netlink_sendreq (struct netlink_handle *h, int type) |
95 | { |
96 | struct req |
97 | { |
98 | struct nlmsghdr nlh; |
99 | struct rtgenmsg g; |
100 | char pad[0]; |
101 | } req; |
102 | struct sockaddr_nl nladdr; |
103 | |
104 | if (h->seq == 0) |
105 | h->seq = time (NULL); |
106 | |
107 | req.nlh.nlmsg_len = sizeof (req); |
108 | req.nlh.nlmsg_type = type; |
109 | req.nlh.nlmsg_flags = NLM_F_ROOT | NLM_F_MATCH | NLM_F_REQUEST; |
110 | req.nlh.nlmsg_pid = 0; |
111 | req.nlh.nlmsg_seq = h->seq; |
112 | req.g.rtgen_family = AF_UNSPEC; |
113 | if (sizeof (req) != offsetof (struct req, pad)) |
114 | memset (req.pad, '\0', sizeof (req) - offsetof (struct req, pad)); |
115 | |
116 | memset (&nladdr, '\0', sizeof (nladdr)); |
117 | nladdr.nl_family = AF_NETLINK; |
118 | |
119 | return TEMP_FAILURE_RETRY (__sendto (h->fd, (void *) &req, sizeof (req), 0, |
120 | (struct sockaddr *) &nladdr, |
121 | sizeof (nladdr))); |
122 | } |
123 | |
124 | |
125 | int |
126 | __netlink_request (struct netlink_handle *h, int type) |
127 | { |
128 | struct netlink_res *nlm_next; |
129 | struct sockaddr_nl nladdr; |
130 | struct nlmsghdr *nlmh; |
131 | ssize_t read_len; |
132 | bool done = false; |
133 | |
134 | #ifdef PAGE_SIZE |
135 | /* Help the compiler optimize out the malloc call if PAGE_SIZE |
136 | is constant and smaller or equal to PTHREAD_STACK_MIN/4. */ |
137 | const size_t buf_size = PAGE_SIZE; |
138 | #else |
139 | const size_t buf_size = __getpagesize (); |
140 | #endif |
141 | bool use_malloc = false; |
142 | char *buf; |
143 | |
144 | if (__libc_use_alloca (buf_size)) |
145 | buf = alloca (buf_size); |
146 | else |
147 | { |
148 | buf = malloc (buf_size); |
149 | if (buf != NULL) |
150 | use_malloc = true; |
151 | else |
152 | goto out_fail; |
153 | } |
154 | |
155 | struct iovec iov = { buf, buf_size }; |
156 | |
157 | if (__netlink_sendreq (h, type) < 0) |
158 | goto out_fail; |
159 | |
160 | while (! done) |
161 | { |
162 | struct msghdr msg = |
163 | { |
164 | (void *) &nladdr, sizeof (nladdr), |
165 | &iov, 1, |
166 | NULL, 0, |
167 | 0 |
168 | }; |
169 | |
170 | read_len = TEMP_FAILURE_RETRY (__recvmsg (h->fd, &msg, 0)); |
171 | __netlink_assert_response (h->fd, read_len); |
172 | if (read_len < 0) |
173 | goto out_fail; |
174 | |
175 | if (nladdr.nl_pid != 0) |
176 | continue; |
177 | |
178 | if (__glibc_unlikely (msg.msg_flags & MSG_TRUNC)) |
179 | goto out_fail; |
180 | |
181 | size_t count = 0; |
182 | size_t remaining_len = read_len; |
183 | for (nlmh = (struct nlmsghdr *) buf; |
184 | NLMSG_OK (nlmh, remaining_len); |
185 | nlmh = (struct nlmsghdr *) NLMSG_NEXT (nlmh, remaining_len)) |
186 | { |
187 | if ((pid_t) nlmh->nlmsg_pid != h->pid |
188 | || nlmh->nlmsg_seq != h->seq) |
189 | continue; |
190 | |
191 | ++count; |
192 | if (nlmh->nlmsg_type == NLMSG_DONE) |
193 | { |
194 | /* We found the end, leave the loop. */ |
195 | done = true; |
196 | break; |
197 | } |
198 | if (nlmh->nlmsg_type == NLMSG_ERROR) |
199 | { |
200 | struct nlmsgerr *nlerr = (struct nlmsgerr *) NLMSG_DATA (nlmh); |
201 | if (nlmh->nlmsg_len < NLMSG_LENGTH (sizeof (struct nlmsgerr))) |
202 | errno = EIO; |
203 | else |
204 | errno = -nlerr->error; |
205 | goto out_fail; |
206 | } |
207 | } |
208 | |
209 | /* If there was nothing with the expected nlmsg_pid and nlmsg_seq, |
210 | there is no point to record it. */ |
211 | if (count == 0) |
212 | continue; |
213 | |
214 | nlm_next = (struct netlink_res *) malloc (sizeof (struct netlink_res) |
215 | + read_len); |
216 | if (nlm_next == NULL) |
217 | goto out_fail; |
218 | nlm_next->next = NULL; |
219 | nlm_next->nlh = memcpy (nlm_next + 1, buf, read_len); |
220 | nlm_next->size = read_len; |
221 | nlm_next->seq = h->seq; |
222 | if (h->nlm_list == NULL) |
223 | h->nlm_list = nlm_next; |
224 | else |
225 | h->end_ptr->next = nlm_next; |
226 | h->end_ptr = nlm_next; |
227 | } |
228 | |
229 | if (use_malloc) |
230 | free (buf); |
231 | return 0; |
232 | |
233 | out_fail: |
234 | if (use_malloc) |
235 | free (buf); |
236 | return -1; |
237 | } |
238 | |
239 | |
240 | void |
241 | __netlink_close (struct netlink_handle *h) |
242 | { |
243 | /* Don't modify errno. */ |
244 | INTERNAL_SYSCALL_DECL (err); |
245 | (void) INTERNAL_SYSCALL (close, err, 1, h->fd); |
246 | } |
247 | |
248 | |
249 | /* Open a NETLINK socket. */ |
250 | int |
251 | __netlink_open (struct netlink_handle *h) |
252 | { |
253 | struct sockaddr_nl nladdr; |
254 | |
255 | h->fd = __socket (PF_NETLINK, SOCK_RAW, NETLINK_ROUTE); |
256 | if (h->fd < 0) |
257 | goto out; |
258 | |
259 | memset (&nladdr, '\0', sizeof (nladdr)); |
260 | nladdr.nl_family = AF_NETLINK; |
261 | if (__bind (h->fd, (struct sockaddr *) &nladdr, sizeof (nladdr)) < 0) |
262 | { |
263 | close_and_out: |
264 | __netlink_close (h); |
265 | out: |
266 | return -1; |
267 | } |
268 | /* Determine the ID the kernel assigned for this netlink connection. |
269 | It is not necessarily the PID if there is more than one socket |
270 | open. */ |
271 | socklen_t addr_len = sizeof (nladdr); |
272 | if (__getsockname (h->fd, (struct sockaddr *) &nladdr, &addr_len) < 0) |
273 | goto close_and_out; |
274 | h->pid = nladdr.nl_pid; |
275 | return 0; |
276 | } |
277 | |
278 | |
279 | /* We know the number of RTM_NEWLINK entries, so we reserve the first |
280 | # of entries for this type. All RTM_NEWADDR entries have an index |
281 | pointer to the RTM_NEWLINK entry. To find the entry, create |
282 | a table to map kernel index entries to our index numbers. |
283 | Since we get at first all RTM_NEWLINK entries, it can never happen |
284 | that a RTM_NEWADDR index is not known to this map. */ |
285 | static int |
286 | internal_function |
287 | map_newlink (int index, struct ifaddrs_storage *ifas, int *map, int max) |
288 | { |
289 | int i; |
290 | |
291 | for (i = 0; i < max; i++) |
292 | { |
293 | if (map[i] == -1) |
294 | { |
295 | map[i] = index; |
296 | if (i > 0) |
297 | ifas[i - 1].ifa.ifa_next = &ifas[i].ifa; |
298 | return i; |
299 | } |
300 | else if (map[i] == index) |
301 | return i; |
302 | } |
303 | |
304 | /* This means interfaces changed between the reading of the |
305 | RTM_GETLINK and RTM_GETADDR information. We have to repeat |
306 | everything. */ |
307 | return -1; |
308 | } |
309 | |
310 | |
311 | /* Create a linked list of `struct ifaddrs' structures, one for each |
312 | network interface on the host machine. If successful, store the |
313 | list in *IFAP and return 0. On errors, return -1 and set `errno'. */ |
314 | static int |
315 | getifaddrs_internal (struct ifaddrs **ifap) |
316 | { |
317 | struct netlink_handle nh = { 0, 0, 0, NULL, NULL }; |
318 | struct netlink_res *nlp; |
319 | struct ifaddrs_storage *ifas; |
320 | unsigned int i, newlink, newaddr, newaddr_idx; |
321 | int *map_newlink_data; |
322 | size_t ifa_data_size = 0; /* Size to allocate for all ifa_data. */ |
323 | char *ifa_data_ptr; /* Pointer to the unused part of memory for |
324 | ifa_data. */ |
325 | int result = 0; |
326 | |
327 | *ifap = NULL; |
328 | |
329 | if (__netlink_open (&nh) < 0) |
330 | return -1; |
331 | |
332 | /* Tell the kernel that we wish to get a list of all |
333 | active interfaces, collect all data for every interface. */ |
334 | if (__netlink_request (&nh, RTM_GETLINK) < 0) |
335 | { |
336 | result = -1; |
337 | goto exit_free; |
338 | } |
339 | |
340 | /* Now ask the kernel for all addresses which are assigned |
341 | to an interface and collect all data for every interface. |
342 | Since we store the addresses after the interfaces in the |
343 | list, we will later always find the interface before the |
344 | corresponding addresses. */ |
345 | ++nh.seq; |
346 | if (__netlink_request (&nh, RTM_GETADDR) < 0) |
347 | { |
348 | result = -1; |
349 | goto exit_free; |
350 | } |
351 | |
352 | /* Count all RTM_NEWLINK and RTM_NEWADDR entries to allocate |
353 | enough memory. */ |
354 | newlink = newaddr = 0; |
355 | for (nlp = nh.nlm_list; nlp; nlp = nlp->next) |
356 | { |
357 | struct nlmsghdr *nlh; |
358 | size_t size = nlp->size; |
359 | |
360 | if (nlp->nlh == NULL) |
361 | continue; |
362 | |
363 | /* Walk through all entries we got from the kernel and look, which |
364 | message type they contain. */ |
365 | for (nlh = nlp->nlh; NLMSG_OK (nlh, size); nlh = NLMSG_NEXT (nlh, size)) |
366 | { |
367 | /* Check if the message is what we want. */ |
368 | if ((pid_t) nlh->nlmsg_pid != nh.pid || nlh->nlmsg_seq != nlp->seq) |
369 | continue; |
370 | |
371 | if (nlh->nlmsg_type == NLMSG_DONE) |
372 | break; /* ok */ |
373 | |
374 | if (nlh->nlmsg_type == RTM_NEWLINK) |
375 | { |
376 | /* A RTM_NEWLINK message can have IFLA_STATS data. We need to |
377 | know the size before creating the list to allocate enough |
378 | memory. */ |
379 | struct ifinfomsg *ifim = (struct ifinfomsg *) NLMSG_DATA (nlh); |
380 | struct rtattr *rta = IFLA_RTA (ifim); |
381 | size_t rtasize = IFLA_PAYLOAD (nlh); |
382 | |
383 | while (RTA_OK (rta, rtasize)) |
384 | { |
385 | size_t rta_payload = RTA_PAYLOAD (rta); |
386 | |
387 | if (rta->rta_type == IFLA_STATS) |
388 | { |
389 | ifa_data_size += rta_payload; |
390 | break; |
391 | } |
392 | else |
393 | rta = RTA_NEXT (rta, rtasize); |
394 | } |
395 | ++newlink; |
396 | } |
397 | else if (nlh->nlmsg_type == RTM_NEWADDR) |
398 | ++newaddr; |
399 | } |
400 | } |
401 | |
402 | /* Return if no interface is up. */ |
403 | if ((newlink + newaddr) == 0) |
404 | goto exit_free; |
405 | |
406 | /* Allocate memory for all entries we have and initialize next |
407 | pointer. */ |
408 | ifas = (struct ifaddrs_storage *) calloc (1, |
409 | (newlink + newaddr) |
410 | * sizeof (struct ifaddrs_storage) |
411 | + ifa_data_size); |
412 | if (ifas == NULL) |
413 | { |
414 | result = -1; |
415 | goto exit_free; |
416 | } |
417 | |
418 | /* Table for mapping kernel index to entry in our list. */ |
419 | map_newlink_data = alloca (newlink * sizeof (int)); |
420 | memset (map_newlink_data, '\xff', newlink * sizeof (int)); |
421 | |
422 | ifa_data_ptr = (char *) &ifas[newlink + newaddr]; |
423 | newaddr_idx = 0; /* Counter for newaddr index. */ |
424 | |
425 | /* Walk through the list of data we got from the kernel. */ |
426 | for (nlp = nh.nlm_list; nlp; nlp = nlp->next) |
427 | { |
428 | struct nlmsghdr *nlh; |
429 | size_t size = nlp->size; |
430 | |
431 | if (nlp->nlh == NULL) |
432 | continue; |
433 | |
434 | /* Walk through one message and look at the type: If it is our |
435 | message, we need RTM_NEWLINK/RTM_NEWADDR and stop if we reach |
436 | the end or we find the end marker (in this case we ignore the |
437 | following data. */ |
438 | for (nlh = nlp->nlh; NLMSG_OK (nlh, size); nlh = NLMSG_NEXT (nlh, size)) |
439 | { |
440 | int ifa_index = 0; |
441 | |
442 | /* Check if the message is the one we want */ |
443 | if ((pid_t) nlh->nlmsg_pid != nh.pid || nlh->nlmsg_seq != nlp->seq) |
444 | continue; |
445 | |
446 | if (nlh->nlmsg_type == NLMSG_DONE) |
447 | break; /* ok */ |
448 | |
449 | if (nlh->nlmsg_type == RTM_NEWLINK) |
450 | { |
451 | /* We found a new interface. Now extract everything from the |
452 | interface data we got and need. */ |
453 | struct ifinfomsg *ifim = (struct ifinfomsg *) NLMSG_DATA (nlh); |
454 | struct rtattr *rta = IFLA_RTA (ifim); |
455 | size_t rtasize = IFLA_PAYLOAD (nlh); |
456 | |
457 | /* Interfaces are stored in the first "newlink" entries |
458 | of our list, starting in the order as we got from the |
459 | kernel. */ |
460 | ifa_index = map_newlink (ifim->ifi_index - 1, ifas, |
461 | map_newlink_data, newlink); |
462 | if (__glibc_unlikely (ifa_index == -1)) |
463 | { |
464 | try_again: |
465 | result = -EAGAIN; |
466 | free (ifas); |
467 | goto exit_free; |
468 | } |
469 | ifas[ifa_index].ifa.ifa_flags = ifim->ifi_flags; |
470 | |
471 | while (RTA_OK (rta, rtasize)) |
472 | { |
473 | char *rta_data = RTA_DATA (rta); |
474 | size_t rta_payload = RTA_PAYLOAD (rta); |
475 | |
476 | switch (rta->rta_type) |
477 | { |
478 | case IFLA_ADDRESS: |
479 | if (rta_payload <= sizeof (ifas[ifa_index].addr)) |
480 | { |
481 | ifas[ifa_index].addr.sl.sll_family = AF_PACKET; |
482 | memcpy (ifas[ifa_index].addr.sl.sll_addr, |
483 | (char *) rta_data, rta_payload); |
484 | ifas[ifa_index].addr.sl.sll_halen = rta_payload; |
485 | ifas[ifa_index].addr.sl.sll_ifindex |
486 | = ifim->ifi_index; |
487 | ifas[ifa_index].addr.sl.sll_hatype = ifim->ifi_type; |
488 | |
489 | ifas[ifa_index].ifa.ifa_addr |
490 | = &ifas[ifa_index].addr.sa; |
491 | } |
492 | break; |
493 | |
494 | case IFLA_BROADCAST: |
495 | if (rta_payload <= sizeof (ifas[ifa_index].broadaddr)) |
496 | { |
497 | ifas[ifa_index].broadaddr.sl.sll_family = AF_PACKET; |
498 | memcpy (ifas[ifa_index].broadaddr.sl.sll_addr, |
499 | (char *) rta_data, rta_payload); |
500 | ifas[ifa_index].broadaddr.sl.sll_halen = rta_payload; |
501 | ifas[ifa_index].broadaddr.sl.sll_ifindex |
502 | = ifim->ifi_index; |
503 | ifas[ifa_index].broadaddr.sl.sll_hatype |
504 | = ifim->ifi_type; |
505 | |
506 | ifas[ifa_index].ifa.ifa_broadaddr |
507 | = &ifas[ifa_index].broadaddr.sa; |
508 | } |
509 | break; |
510 | |
511 | case IFLA_IFNAME: /* Name of Interface */ |
512 | if ((rta_payload + 1) <= sizeof (ifas[ifa_index].name)) |
513 | { |
514 | ifas[ifa_index].ifa.ifa_name = ifas[ifa_index].name; |
515 | *(char *) __mempcpy (ifas[ifa_index].name, rta_data, |
516 | rta_payload) = '\0'; |
517 | } |
518 | break; |
519 | |
520 | case IFLA_STATS: /* Statistics of Interface */ |
521 | ifas[ifa_index].ifa.ifa_data = ifa_data_ptr; |
522 | ifa_data_ptr += rta_payload; |
523 | memcpy (ifas[ifa_index].ifa.ifa_data, rta_data, |
524 | rta_payload); |
525 | break; |
526 | |
527 | case IFLA_UNSPEC: |
528 | break; |
529 | case IFLA_MTU: |
530 | break; |
531 | case IFLA_LINK: |
532 | break; |
533 | case IFLA_QDISC: |
534 | break; |
535 | default: |
536 | break; |
537 | } |
538 | |
539 | rta = RTA_NEXT (rta, rtasize); |
540 | } |
541 | } |
542 | else if (nlh->nlmsg_type == RTM_NEWADDR) |
543 | { |
544 | struct ifaddrmsg *ifam = (struct ifaddrmsg *) NLMSG_DATA (nlh); |
545 | struct rtattr *rta = IFA_RTA (ifam); |
546 | size_t rtasize = IFA_PAYLOAD (nlh); |
547 | |
548 | /* New Addresses are stored in the order we got them from |
549 | the kernel after the interfaces. Theoretically it is possible |
550 | that we have holes in the interface part of the list, |
551 | but we always have already the interface for this address. */ |
552 | ifa_index = newlink + newaddr_idx; |
553 | int idx = map_newlink (ifam->ifa_index - 1, ifas, |
554 | map_newlink_data, newlink); |
555 | if (__glibc_unlikely (idx == -1)) |
556 | goto try_again; |
557 | ifas[ifa_index].ifa.ifa_flags = ifas[idx].ifa.ifa_flags; |
558 | if (ifa_index > 0) |
559 | ifas[ifa_index - 1].ifa.ifa_next = &ifas[ifa_index].ifa; |
560 | ++newaddr_idx; |
561 | |
562 | while (RTA_OK (rta, rtasize)) |
563 | { |
564 | char *rta_data = RTA_DATA (rta); |
565 | size_t rta_payload = RTA_PAYLOAD (rta); |
566 | |
567 | switch (rta->rta_type) |
568 | { |
569 | case IFA_ADDRESS: |
570 | { |
571 | struct sockaddr *sa; |
572 | |
573 | if (ifas[ifa_index].ifa.ifa_addr != NULL) |
574 | { |
575 | /* In a point-to-poing network IFA_ADDRESS |
576 | contains the destination address, local |
577 | address is supplied in IFA_LOCAL attribute. |
578 | destination address and broadcast address |
579 | are stored in an union, so it doesn't matter |
580 | which name we use. */ |
581 | ifas[ifa_index].ifa.ifa_broadaddr |
582 | = &ifas[ifa_index].broadaddr.sa; |
583 | sa = &ifas[ifa_index].broadaddr.sa; |
584 | } |
585 | else |
586 | { |
587 | ifas[ifa_index].ifa.ifa_addr |
588 | = &ifas[ifa_index].addr.sa; |
589 | sa = &ifas[ifa_index].addr.sa; |
590 | } |
591 | |
592 | sa->sa_family = ifam->ifa_family; |
593 | |
594 | switch (ifam->ifa_family) |
595 | { |
596 | case AF_INET: |
597 | /* Size must match that of an address for IPv4. */ |
598 | if (rta_payload == 4) |
599 | memcpy (&((struct sockaddr_in *) sa)->sin_addr, |
600 | rta_data, rta_payload); |
601 | break; |
602 | |
603 | case AF_INET6: |
604 | /* Size must match that of an address for IPv6. */ |
605 | if (rta_payload == 16) |
606 | { |
607 | memcpy (&((struct sockaddr_in6 *) sa)->sin6_addr, |
608 | rta_data, rta_payload); |
609 | if (IN6_IS_ADDR_LINKLOCAL (rta_data) |
610 | || IN6_IS_ADDR_MC_LINKLOCAL (rta_data)) |
611 | ((struct sockaddr_in6 *) sa)->sin6_scope_id |
612 | = ifam->ifa_index; |
613 | } |
614 | break; |
615 | |
616 | default: |
617 | if (rta_payload <= sizeof (ifas[ifa_index].addr)) |
618 | memcpy (sa->sa_data, rta_data, rta_payload); |
619 | break; |
620 | } |
621 | } |
622 | break; |
623 | |
624 | case IFA_LOCAL: |
625 | if (ifas[ifa_index].ifa.ifa_addr != NULL) |
626 | { |
627 | /* If ifa_addr is set and we get IFA_LOCAL, |
628 | assume we have a point-to-point network. |
629 | Move address to correct field. */ |
630 | ifas[ifa_index].broadaddr = ifas[ifa_index].addr; |
631 | ifas[ifa_index].ifa.ifa_broadaddr |
632 | = &ifas[ifa_index].broadaddr.sa; |
633 | memset (&ifas[ifa_index].addr, '\0', |
634 | sizeof (ifas[ifa_index].addr)); |
635 | } |
636 | |
637 | ifas[ifa_index].ifa.ifa_addr = &ifas[ifa_index].addr.sa; |
638 | ifas[ifa_index].ifa.ifa_addr->sa_family |
639 | = ifam->ifa_family; |
640 | |
641 | switch (ifam->ifa_family) |
642 | { |
643 | case AF_INET: |
644 | /* Size must match that of an address for IPv4. */ |
645 | if (rta_payload == 4) |
646 | memcpy (&ifas[ifa_index].addr.s4.sin_addr, |
647 | rta_data, rta_payload); |
648 | break; |
649 | |
650 | case AF_INET6: |
651 | /* Size must match that of an address for IPv6. */ |
652 | if (rta_payload == 16) |
653 | { |
654 | memcpy (&ifas[ifa_index].addr.s6.sin6_addr, |
655 | rta_data, rta_payload); |
656 | if (IN6_IS_ADDR_LINKLOCAL (rta_data) |
657 | || IN6_IS_ADDR_MC_LINKLOCAL (rta_data)) |
658 | ifas[ifa_index].addr.s6.sin6_scope_id = |
659 | ifam->ifa_index; |
660 | } |
661 | break; |
662 | |
663 | default: |
664 | if (rta_payload <= sizeof (ifas[ifa_index].addr)) |
665 | memcpy (ifas[ifa_index].addr.sa.sa_data, |
666 | rta_data, rta_payload); |
667 | break; |
668 | } |
669 | break; |
670 | |
671 | case IFA_BROADCAST: |
672 | /* We get IFA_BROADCAST, so IFA_LOCAL was too much. */ |
673 | if (ifas[ifa_index].ifa.ifa_broadaddr != NULL) |
674 | memset (&ifas[ifa_index].broadaddr, '\0', |
675 | sizeof (ifas[ifa_index].broadaddr)); |
676 | |
677 | ifas[ifa_index].ifa.ifa_broadaddr |
678 | = &ifas[ifa_index].broadaddr.sa; |
679 | ifas[ifa_index].ifa.ifa_broadaddr->sa_family |
680 | = ifam->ifa_family; |
681 | |
682 | switch (ifam->ifa_family) |
683 | { |
684 | case AF_INET: |
685 | /* Size must match that of an address for IPv4. */ |
686 | if (rta_payload == 4) |
687 | memcpy (&ifas[ifa_index].broadaddr.s4.sin_addr, |
688 | rta_data, rta_payload); |
689 | break; |
690 | |
691 | case AF_INET6: |
692 | /* Size must match that of an address for IPv6. */ |
693 | if (rta_payload == 16) |
694 | { |
695 | memcpy (&ifas[ifa_index].broadaddr.s6.sin6_addr, |
696 | rta_data, rta_payload); |
697 | if (IN6_IS_ADDR_LINKLOCAL (rta_data) |
698 | || IN6_IS_ADDR_MC_LINKLOCAL (rta_data)) |
699 | ifas[ifa_index].broadaddr.s6.sin6_scope_id |
700 | = ifam->ifa_index; |
701 | } |
702 | break; |
703 | |
704 | default: |
705 | if (rta_payload <= sizeof (ifas[ifa_index].addr)) |
706 | memcpy (&ifas[ifa_index].broadaddr.sa.sa_data, |
707 | rta_data, rta_payload); |
708 | break; |
709 | } |
710 | break; |
711 | |
712 | case IFA_LABEL: |
713 | if (rta_payload + 1 <= sizeof (ifas[ifa_index].name)) |
714 | { |
715 | ifas[ifa_index].ifa.ifa_name = ifas[ifa_index].name; |
716 | *(char *) __mempcpy (ifas[ifa_index].name, rta_data, |
717 | rta_payload) = '\0'; |
718 | } |
719 | else |
720 | abort (); |
721 | break; |
722 | |
723 | case IFA_UNSPEC: |
724 | break; |
725 | case IFA_CACHEINFO: |
726 | break; |
727 | default: |
728 | break; |
729 | } |
730 | |
731 | rta = RTA_NEXT (rta, rtasize); |
732 | } |
733 | |
734 | /* If we didn't get the interface name with the |
735 | address, use the name from the interface entry. */ |
736 | if (ifas[ifa_index].ifa.ifa_name == NULL) |
737 | { |
738 | int idx = map_newlink (ifam->ifa_index - 1, ifas, |
739 | map_newlink_data, newlink); |
740 | if (__glibc_unlikely (idx == -1)) |
741 | goto try_again; |
742 | ifas[ifa_index].ifa.ifa_name = ifas[idx].ifa.ifa_name; |
743 | } |
744 | |
745 | /* Calculate the netmask. */ |
746 | if (ifas[ifa_index].ifa.ifa_addr |
747 | && ifas[ifa_index].ifa.ifa_addr->sa_family != AF_UNSPEC |
748 | && ifas[ifa_index].ifa.ifa_addr->sa_family != AF_PACKET) |
749 | { |
750 | uint32_t max_prefixlen = 0; |
751 | char *cp = NULL; |
752 | |
753 | ifas[ifa_index].ifa.ifa_netmask |
754 | = &ifas[ifa_index].netmask.sa; |
755 | |
756 | switch (ifas[ifa_index].ifa.ifa_addr->sa_family) |
757 | { |
758 | case AF_INET: |
759 | cp = (char *) &ifas[ifa_index].netmask.s4.sin_addr; |
760 | max_prefixlen = 32; |
761 | break; |
762 | |
763 | case AF_INET6: |
764 | cp = (char *) &ifas[ifa_index].netmask.s6.sin6_addr; |
765 | max_prefixlen = 128; |
766 | break; |
767 | } |
768 | |
769 | ifas[ifa_index].ifa.ifa_netmask->sa_family |
770 | = ifas[ifa_index].ifa.ifa_addr->sa_family; |
771 | |
772 | if (cp != NULL) |
773 | { |
774 | unsigned int preflen; |
775 | |
776 | if (ifam->ifa_prefixlen > max_prefixlen) |
777 | preflen = max_prefixlen; |
778 | else |
779 | preflen = ifam->ifa_prefixlen; |
780 | |
781 | for (i = 0; i < preflen / 8; i++) |
782 | *cp++ = 0xff; |
783 | if (preflen % 8) |
784 | *cp = 0xff << (8 - preflen % 8); |
785 | } |
786 | } |
787 | } |
788 | } |
789 | } |
790 | |
791 | assert (ifa_data_ptr <= (char *) &ifas[newlink + newaddr] + ifa_data_size); |
792 | |
793 | if (newaddr_idx > 0) |
794 | { |
795 | for (i = 0; i < newlink; ++i) |
796 | if (map_newlink_data[i] == -1) |
797 | { |
798 | /* We have fewer links then we anticipated. Adjust the |
799 | forward pointer to the first address entry. */ |
800 | ifas[i - 1].ifa.ifa_next = &ifas[newlink].ifa; |
801 | } |
802 | |
803 | if (i == 0 && newlink > 0) |
804 | /* No valid link, but we allocated memory. We have to |
805 | populate the first entry. */ |
806 | memmove (ifas, &ifas[newlink], sizeof (struct ifaddrs_storage)); |
807 | } |
808 | |
809 | *ifap = &ifas[0].ifa; |
810 | |
811 | exit_free: |
812 | __netlink_free_handle (&nh); |
813 | __netlink_close (&nh); |
814 | |
815 | return result; |
816 | } |
817 | |
818 | |
819 | /* Create a linked list of `struct ifaddrs' structures, one for each |
820 | network interface on the host machine. If successful, store the |
821 | list in *IFAP and return 0. On errors, return -1 and set `errno'. */ |
822 | int |
823 | __getifaddrs (struct ifaddrs **ifap) |
824 | { |
825 | int res; |
826 | |
827 | do |
828 | res = getifaddrs_internal (ifap); |
829 | while (res == -EAGAIN); |
830 | |
831 | return res; |
832 | } |
833 | weak_alias (__getifaddrs, getifaddrs) |
834 | libc_hidden_weak (getifaddrs) |
835 | |
836 | |
837 | void |
838 | __freeifaddrs (struct ifaddrs *ifa) |
839 | { |
840 | free (ifa); |
841 | } |
842 | weak_alias (__freeifaddrs, freeifaddrs) |
843 | libc_hidden_weak (freeifaddrs) |
844 | |