1 /*-------------------------------------------------------------------------
2 *
3 * ifaddr.c
4 * IP netmask calculations, and enumerating network interfaces.
5 *
6 * Portions Copyright (c) 1996-2018, PostgreSQL Global Development Group
7 * Portions Copyright (c) 1994, Regents of the University of California
8 *
9 *
10 * IDENTIFICATION
11 * src/backend/libpq/ifaddr.c
12 *
13 * This file and the IPV6 implementation were initially provided by
14 * Nigel Kukard <nkukard@lbsd.net>, Linux Based Systems Design
15 * http://www.lbsd.net.
16 *
17 *-------------------------------------------------------------------------
18 */
19
20 #include "postgres.h"
21
22 #include <unistd.h>
23 #include <sys/stat.h>
24 #include <sys/socket.h>
25 #include <netdb.h>
26 #include <netinet/in.h>
27 #ifdef HAVE_NETINET_TCP_H
28 #include <netinet/tcp.h>
29 #endif
30 #include <sys/file.h>
31
32 #include "libpq/ifaddr.h"
33 #include "port/pg_bswap.h"
34
35 static int range_sockaddr_AF_INET(const struct sockaddr_in *addr,
36 const struct sockaddr_in *netaddr,
37 const struct sockaddr_in *netmask);
38
39 #ifdef HAVE_IPV6
40 static int range_sockaddr_AF_INET6(const struct sockaddr_in6 *addr,
41 const struct sockaddr_in6 *netaddr,
42 const struct sockaddr_in6 *netmask);
43 #endif
44
45
46 /*
47 * pg_range_sockaddr - is addr within the subnet specified by netaddr/netmask ?
48 *
49 * Note: caller must already have verified that all three addresses are
50 * in the same address family; and AF_UNIX addresses are not supported.
51 */
52 int
pg_range_sockaddr(const struct sockaddr_storage * addr,const struct sockaddr_storage * netaddr,const struct sockaddr_storage * netmask)53 pg_range_sockaddr(const struct sockaddr_storage *addr,
54 const struct sockaddr_storage *netaddr,
55 const struct sockaddr_storage *netmask)
56 {
57 if (addr->ss_family == AF_INET)
58 return range_sockaddr_AF_INET((const struct sockaddr_in *) addr,
59 (const struct sockaddr_in *) netaddr,
60 (const struct sockaddr_in *) netmask);
61 #ifdef HAVE_IPV6
62 else if (addr->ss_family == AF_INET6)
63 return range_sockaddr_AF_INET6((const struct sockaddr_in6 *) addr,
64 (const struct sockaddr_in6 *) netaddr,
65 (const struct sockaddr_in6 *) netmask);
66 #endif
67 else
68 return 0;
69 }
70
71 static int
range_sockaddr_AF_INET(const struct sockaddr_in * addr,const struct sockaddr_in * netaddr,const struct sockaddr_in * netmask)72 range_sockaddr_AF_INET(const struct sockaddr_in *addr,
73 const struct sockaddr_in *netaddr,
74 const struct sockaddr_in *netmask)
75 {
76 if (((addr->sin_addr.s_addr ^ netaddr->sin_addr.s_addr) &
77 netmask->sin_addr.s_addr) == 0)
78 return 1;
79 else
80 return 0;
81 }
82
83
84 #ifdef HAVE_IPV6
85
86 static int
range_sockaddr_AF_INET6(const struct sockaddr_in6 * addr,const struct sockaddr_in6 * netaddr,const struct sockaddr_in6 * netmask)87 range_sockaddr_AF_INET6(const struct sockaddr_in6 *addr,
88 const struct sockaddr_in6 *netaddr,
89 const struct sockaddr_in6 *netmask)
90 {
91 int i;
92
93 for (i = 0; i < 16; i++)
94 {
95 if (((addr->sin6_addr.s6_addr[i] ^ netaddr->sin6_addr.s6_addr[i]) &
96 netmask->sin6_addr.s6_addr[i]) != 0)
97 return 0;
98 }
99
100 return 1;
101 }
102 #endif /* HAVE_IPV6 */
103
104 /*
105 * pg_sockaddr_cidr_mask - make a network mask of the appropriate family
106 * and required number of significant bits
107 *
108 * numbits can be null, in which case the mask is fully set.
109 *
110 * The resulting mask is placed in *mask, which had better be big enough.
111 *
112 * Return value is 0 if okay, -1 if not.
113 */
114 int
pg_sockaddr_cidr_mask(struct sockaddr_storage * mask,char * numbits,int family)115 pg_sockaddr_cidr_mask(struct sockaddr_storage *mask, char *numbits, int family)
116 {
117 long bits;
118 char *endptr;
119
120 if (numbits == NULL)
121 {
122 bits = (family == AF_INET) ? 32 : 128;
123 }
124 else
125 {
126 bits = strtol(numbits, &endptr, 10);
127 if (*numbits == '\0' || *endptr != '\0')
128 return -1;
129 }
130
131 switch (family)
132 {
133 case AF_INET:
134 {
135 struct sockaddr_in mask4;
136 long maskl;
137
138 if (bits < 0 || bits > 32)
139 return -1;
140 memset(&mask4, 0, sizeof(mask4));
141 /* avoid "x << 32", which is not portable */
142 if (bits > 0)
143 maskl = (0xffffffffUL << (32 - (int) bits))
144 & 0xffffffffUL;
145 else
146 maskl = 0;
147 mask4.sin_addr.s_addr = pg_hton32(maskl);
148 memcpy(mask, &mask4, sizeof(mask4));
149 break;
150 }
151
152 #ifdef HAVE_IPV6
153 case AF_INET6:
154 {
155 struct sockaddr_in6 mask6;
156 int i;
157
158 if (bits < 0 || bits > 128)
159 return -1;
160 memset(&mask6, 0, sizeof(mask6));
161 for (i = 0; i < 16; i++)
162 {
163 if (bits <= 0)
164 mask6.sin6_addr.s6_addr[i] = 0;
165 else if (bits >= 8)
166 mask6.sin6_addr.s6_addr[i] = 0xff;
167 else
168 {
169 mask6.sin6_addr.s6_addr[i] =
170 (0xff << (8 - (int) bits)) & 0xff;
171 }
172 bits -= 8;
173 }
174 memcpy(mask, &mask6, sizeof(mask6));
175 break;
176 }
177 #endif
178 default:
179 return -1;
180 }
181
182 mask->ss_family = family;
183 return 0;
184 }
185
186
187 /*
188 * Run the callback function for the addr/mask, after making sure the
189 * mask is sane for the addr.
190 */
191 static void
run_ifaddr_callback(PgIfAddrCallback callback,void * cb_data,struct sockaddr * addr,struct sockaddr * mask)192 run_ifaddr_callback(PgIfAddrCallback callback, void *cb_data,
193 struct sockaddr *addr, struct sockaddr *mask)
194 {
195 struct sockaddr_storage fullmask;
196
197 if (!addr)
198 return;
199
200 /* Check that the mask is valid */
201 if (mask)
202 {
203 if (mask->sa_family != addr->sa_family)
204 {
205 mask = NULL;
206 }
207 else if (mask->sa_family == AF_INET)
208 {
209 if (((struct sockaddr_in *) mask)->sin_addr.s_addr == INADDR_ANY)
210 mask = NULL;
211 }
212 #ifdef HAVE_IPV6
213 else if (mask->sa_family == AF_INET6)
214 {
215 if (IN6_IS_ADDR_UNSPECIFIED(&((struct sockaddr_in6 *) mask)->sin6_addr))
216 mask = NULL;
217 }
218 #endif
219 }
220
221 /* If mask is invalid, generate our own fully-set mask */
222 if (!mask)
223 {
224 pg_sockaddr_cidr_mask(&fullmask, NULL, addr->sa_family);
225 mask = (struct sockaddr *) &fullmask;
226 }
227
228 (*callback) (addr, mask, cb_data);
229 }
230
231 #ifdef WIN32
232
233 #include <winsock2.h>
234 #include <ws2tcpip.h>
235
236 /*
237 * Enumerate the system's network interface addresses and call the callback
238 * for each one. Returns 0 if successful, -1 if trouble.
239 *
240 * This version is for Win32. Uses the Winsock 2 functions (ie: ws2_32.dll)
241 */
242 int
pg_foreach_ifaddr(PgIfAddrCallback callback,void * cb_data)243 pg_foreach_ifaddr(PgIfAddrCallback callback, void *cb_data)
244 {
245 INTERFACE_INFO *ptr,
246 *ii = NULL;
247 unsigned long length,
248 i;
249 unsigned long n_ii = 0;
250 SOCKET sock;
251 int error;
252
253 sock = WSASocket(AF_INET, SOCK_DGRAM, 0, 0, 0, 0);
254 if (sock == INVALID_SOCKET)
255 return -1;
256
257 while (n_ii < 1024)
258 {
259 n_ii += 64;
260 ptr = realloc(ii, sizeof(INTERFACE_INFO) * n_ii);
261 if (!ptr)
262 {
263 free(ii);
264 closesocket(sock);
265 errno = ENOMEM;
266 return -1;
267 }
268
269 ii = ptr;
270 if (WSAIoctl(sock, SIO_GET_INTERFACE_LIST, 0, 0,
271 ii, n_ii * sizeof(INTERFACE_INFO),
272 &length, 0, 0) == SOCKET_ERROR)
273 {
274 error = WSAGetLastError();
275 if (error == WSAEFAULT || error == WSAENOBUFS)
276 continue; /* need to make the buffer bigger */
277 closesocket(sock);
278 free(ii);
279 return -1;
280 }
281
282 break;
283 }
284
285 for (i = 0; i < length / sizeof(INTERFACE_INFO); ++i)
286 run_ifaddr_callback(callback, cb_data,
287 (struct sockaddr *) &ii[i].iiAddress,
288 (struct sockaddr *) &ii[i].iiNetmask);
289
290 closesocket(sock);
291 free(ii);
292 return 0;
293 }
294 #elif HAVE_GETIFADDRS /* && !WIN32 */
295
296 #ifdef HAVE_IFADDRS_H
297 #include <ifaddrs.h>
298 #endif
299
300 /*
301 * Enumerate the system's network interface addresses and call the callback
302 * for each one. Returns 0 if successful, -1 if trouble.
303 *
304 * This version uses the getifaddrs() interface, which is available on
305 * BSDs, AIX, and modern Linux.
306 */
307 int
pg_foreach_ifaddr(PgIfAddrCallback callback,void * cb_data)308 pg_foreach_ifaddr(PgIfAddrCallback callback, void *cb_data)
309 {
310 struct ifaddrs *ifa,
311 *l;
312
313 if (getifaddrs(&ifa) < 0)
314 return -1;
315
316 for (l = ifa; l; l = l->ifa_next)
317 run_ifaddr_callback(callback, cb_data,
318 l->ifa_addr, l->ifa_netmask);
319
320 freeifaddrs(ifa);
321 return 0;
322 }
323 #else /* !HAVE_GETIFADDRS && !WIN32 */
324
325 #include <sys/ioctl.h>
326
327 #ifdef HAVE_NET_IF_H
328 #include <net/if.h>
329 #endif
330
331 #ifdef HAVE_SYS_SOCKIO_H
332 #include <sys/sockio.h>
333 #endif
334
335 /*
336 * SIOCGIFCONF does not return IPv6 addresses on Solaris
337 * and HP/UX. So we prefer SIOCGLIFCONF if it's available.
338 *
339 * On HP/UX, however, it *only* returns IPv6 addresses,
340 * and the structs are named slightly differently too.
341 * We'd have to do another call with SIOCGIFCONF to get the
342 * IPv4 addresses as well. We don't currently bother, just
343 * fall back to SIOCGIFCONF on HP/UX.
344 */
345
346 #if defined(SIOCGLIFCONF) && !defined(__hpux)
347
348 /*
349 * Enumerate the system's network interface addresses and call the callback
350 * for each one. Returns 0 if successful, -1 if trouble.
351 *
352 * This version uses ioctl(SIOCGLIFCONF).
353 */
354 int
pg_foreach_ifaddr(PgIfAddrCallback callback,void * cb_data)355 pg_foreach_ifaddr(PgIfAddrCallback callback, void *cb_data)
356 {
357 struct lifconf lifc;
358 struct lifreq *lifr,
359 lmask;
360 struct sockaddr *addr,
361 *mask;
362 char *ptr,
363 *buffer = NULL;
364 size_t n_buffer = 1024;
365 pgsocket sock,
366 fd;
367
368 #ifdef HAVE_IPV6
369 pgsocket sock6;
370 #endif
371 int i,
372 total;
373
374 sock = socket(AF_INET, SOCK_DGRAM, 0);
375 if (sock == PGINVALID_SOCKET)
376 return -1;
377
378 while (n_buffer < 1024 * 100)
379 {
380 n_buffer += 1024;
381 ptr = realloc(buffer, n_buffer);
382 if (!ptr)
383 {
384 free(buffer);
385 close(sock);
386 errno = ENOMEM;
387 return -1;
388 }
389
390 memset(&lifc, 0, sizeof(lifc));
391 lifc.lifc_family = AF_UNSPEC;
392 lifc.lifc_buf = buffer = ptr;
393 lifc.lifc_len = n_buffer;
394
395 if (ioctl(sock, SIOCGLIFCONF, &lifc) < 0)
396 {
397 if (errno == EINVAL)
398 continue;
399 free(buffer);
400 close(sock);
401 return -1;
402 }
403
404 /*
405 * Some Unixes try to return as much data as possible, with no
406 * indication of whether enough space allocated. Don't believe we have
407 * it all unless there's lots of slop.
408 */
409 if (lifc.lifc_len < n_buffer - 1024)
410 break;
411 }
412
413 #ifdef HAVE_IPV6
414 /* We'll need an IPv6 socket too for the SIOCGLIFNETMASK ioctls */
415 sock6 = socket(AF_INET6, SOCK_DGRAM, 0);
416 if (sock6 == PGINVALID_SOCKET)
417 {
418 free(buffer);
419 close(sock);
420 return -1;
421 }
422 #endif
423
424 total = lifc.lifc_len / sizeof(struct lifreq);
425 lifr = lifc.lifc_req;
426 for (i = 0; i < total; ++i)
427 {
428 addr = (struct sockaddr *) &lifr[i].lifr_addr;
429 memcpy(&lmask, &lifr[i], sizeof(struct lifreq));
430 #ifdef HAVE_IPV6
431 fd = (addr->sa_family == AF_INET6) ? sock6 : sock;
432 #else
433 fd = sock;
434 #endif
435 if (ioctl(fd, SIOCGLIFNETMASK, &lmask) < 0)
436 mask = NULL;
437 else
438 mask = (struct sockaddr *) &lmask.lifr_addr;
439 run_ifaddr_callback(callback, cb_data, addr, mask);
440 }
441
442 free(buffer);
443 close(sock);
444 #ifdef HAVE_IPV6
445 close(sock6);
446 #endif
447 return 0;
448 }
449 #elif defined(SIOCGIFCONF)
450
451 /*
452 * Remaining Unixes use SIOCGIFCONF. Some only return IPv4 information
453 * here, so this is the least preferred method. Note that there is no
454 * standard way to iterate the struct ifreq returned in the array.
455 * On some OSs the structures are padded large enough for any address,
456 * on others you have to calculate the size of the struct ifreq.
457 */
458
459 /* Some OSs have _SIZEOF_ADDR_IFREQ, so just use that */
460 #ifndef _SIZEOF_ADDR_IFREQ
461
462 /* Calculate based on sockaddr.sa_len */
463 #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN
464 #define _SIZEOF_ADDR_IFREQ(ifr) \
465 ((ifr).ifr_addr.sa_len > sizeof(struct sockaddr) ? \
466 (sizeof(struct ifreq) - sizeof(struct sockaddr) + \
467 (ifr).ifr_addr.sa_len) : sizeof(struct ifreq))
468
469 /* Padded ifreq structure, simple */
470 #else
471 #define _SIZEOF_ADDR_IFREQ(ifr) \
472 sizeof (struct ifreq)
473 #endif
474 #endif /* !_SIZEOF_ADDR_IFREQ */
475
476 /*
477 * Enumerate the system's network interface addresses and call the callback
478 * for each one. Returns 0 if successful, -1 if trouble.
479 *
480 * This version uses ioctl(SIOCGIFCONF).
481 */
482 int
pg_foreach_ifaddr(PgIfAddrCallback callback,void * cb_data)483 pg_foreach_ifaddr(PgIfAddrCallback callback, void *cb_data)
484 {
485 struct ifconf ifc;
486 struct ifreq *ifr,
487 *end,
488 addr,
489 mask;
490 char *ptr,
491 *buffer = NULL;
492 size_t n_buffer = 1024;
493 pgsocket sock;
494
495 sock = socket(AF_INET, SOCK_DGRAM, 0);
496 if (sock == PGINVALID_SOCKET)
497 return -1;
498
499 while (n_buffer < 1024 * 100)
500 {
501 n_buffer += 1024;
502 ptr = realloc(buffer, n_buffer);
503 if (!ptr)
504 {
505 free(buffer);
506 close(sock);
507 errno = ENOMEM;
508 return -1;
509 }
510
511 memset(&ifc, 0, sizeof(ifc));
512 ifc.ifc_buf = buffer = ptr;
513 ifc.ifc_len = n_buffer;
514
515 if (ioctl(sock, SIOCGIFCONF, &ifc) < 0)
516 {
517 if (errno == EINVAL)
518 continue;
519 free(buffer);
520 close(sock);
521 return -1;
522 }
523
524 /*
525 * Some Unixes try to return as much data as possible, with no
526 * indication of whether enough space allocated. Don't believe we have
527 * it all unless there's lots of slop.
528 */
529 if (ifc.ifc_len < n_buffer - 1024)
530 break;
531 }
532
533 end = (struct ifreq *) (buffer + ifc.ifc_len);
534 for (ifr = ifc.ifc_req; ifr < end;)
535 {
536 memcpy(&addr, ifr, sizeof(addr));
537 memcpy(&mask, ifr, sizeof(mask));
538 if (ioctl(sock, SIOCGIFADDR, &addr, sizeof(addr)) == 0 &&
539 ioctl(sock, SIOCGIFNETMASK, &mask, sizeof(mask)) == 0)
540 run_ifaddr_callback(callback, cb_data,
541 &addr.ifr_addr, &mask.ifr_addr);
542 ifr = (struct ifreq *) ((char *) ifr + _SIZEOF_ADDR_IFREQ(*ifr));
543 }
544
545 free(buffer);
546 close(sock);
547 return 0;
548 }
549 #else /* !defined(SIOCGIFCONF) */
550
551 /*
552 * Enumerate the system's network interface addresses and call the callback
553 * for each one. Returns 0 if successful, -1 if trouble.
554 *
555 * This version is our fallback if there's no known way to get the
556 * interface addresses. Just return the standard loopback addresses.
557 */
558 int
pg_foreach_ifaddr(PgIfAddrCallback callback,void * cb_data)559 pg_foreach_ifaddr(PgIfAddrCallback callback, void *cb_data)
560 {
561 struct sockaddr_in addr;
562 struct sockaddr_storage mask;
563
564 #ifdef HAVE_IPV6
565 struct sockaddr_in6 addr6;
566 #endif
567
568 /* addr 127.0.0.1/8 */
569 memset(&addr, 0, sizeof(addr));
570 addr.sin_family = AF_INET;
571 addr.sin_addr.s_addr = pg_ntoh32(0x7f000001);
572 memset(&mask, 0, sizeof(mask));
573 pg_sockaddr_cidr_mask(&mask, "8", AF_INET);
574 run_ifaddr_callback(callback, cb_data,
575 (struct sockaddr *) &addr,
576 (struct sockaddr *) &mask);
577
578 #ifdef HAVE_IPV6
579 /* addr ::1/128 */
580 memset(&addr6, 0, sizeof(addr6));
581 addr6.sin6_family = AF_INET6;
582 addr6.sin6_addr.s6_addr[15] = 1;
583 memset(&mask, 0, sizeof(mask));
584 pg_sockaddr_cidr_mask(&mask, "128", AF_INET6);
585 run_ifaddr_callback(callback, cb_data,
586 (struct sockaddr *) &addr6,
587 (struct sockaddr *) &mask);
588 #endif
589
590 return 0;
591 }
592 #endif /* !defined(SIOCGIFCONF) */
593
594 #endif /* !HAVE_GETIFADDRS */
595