PostgreSQL Source Code git master
ifaddr.c
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1/*-------------------------------------------------------------------------
2 *
3 * ifaddr.c
4 * IP netmask calculations, and enumerating network interfaces.
5 *
6 * Portions Copyright (c) 1996-2025, 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#include <netinet/tcp.h>
28#include <sys/file.h>
29
30#include "libpq/ifaddr.h"
31#include "port/pg_bswap.h"
32
33static int range_sockaddr_AF_INET(const struct sockaddr_in *addr,
34 const struct sockaddr_in *netaddr,
35 const struct sockaddr_in *netmask);
36
37static int range_sockaddr_AF_INET6(const struct sockaddr_in6 *addr,
38 const struct sockaddr_in6 *netaddr,
39 const struct sockaddr_in6 *netmask);
40
41
42/*
43 * pg_range_sockaddr - is addr within the subnet specified by netaddr/netmask ?
44 *
45 * Note: caller must already have verified that all three addresses are
46 * in the same address family; and AF_UNIX addresses are not supported.
47 */
48int
49pg_range_sockaddr(const struct sockaddr_storage *addr,
50 const struct sockaddr_storage *netaddr,
51 const struct sockaddr_storage *netmask)
52{
53 if (addr->ss_family == AF_INET)
54 return range_sockaddr_AF_INET((const struct sockaddr_in *) addr,
55 (const struct sockaddr_in *) netaddr,
56 (const struct sockaddr_in *) netmask);
57 else if (addr->ss_family == AF_INET6)
58 return range_sockaddr_AF_INET6((const struct sockaddr_in6 *) addr,
59 (const struct sockaddr_in6 *) netaddr,
60 (const struct sockaddr_in6 *) netmask);
61 else
62 return 0;
63}
64
65static int
66range_sockaddr_AF_INET(const struct sockaddr_in *addr,
67 const struct sockaddr_in *netaddr,
68 const struct sockaddr_in *netmask)
69{
70 if (((addr->sin_addr.s_addr ^ netaddr->sin_addr.s_addr) &
71 netmask->sin_addr.s_addr) == 0)
72 return 1;
73 else
74 return 0;
75}
76
77static int
78range_sockaddr_AF_INET6(const struct sockaddr_in6 *addr,
79 const struct sockaddr_in6 *netaddr,
80 const struct sockaddr_in6 *netmask)
81{
82 int i;
83
84 for (i = 0; i < 16; i++)
85 {
86 if (((addr->sin6_addr.s6_addr[i] ^ netaddr->sin6_addr.s6_addr[i]) &
87 netmask->sin6_addr.s6_addr[i]) != 0)
88 return 0;
89 }
90
91 return 1;
92}
93
94/*
95 * pg_sockaddr_cidr_mask - make a network mask of the appropriate family
96 * and required number of significant bits
97 *
98 * numbits can be null, in which case the mask is fully set.
99 *
100 * The resulting mask is placed in *mask, which had better be big enough.
101 *
102 * Return value is 0 if okay, -1 if not.
103 */
104int
105pg_sockaddr_cidr_mask(struct sockaddr_storage *mask, char *numbits, int family)
106{
107 long bits;
108 char *endptr;
109
110 if (numbits == NULL)
111 {
112 bits = (family == AF_INET) ? 32 : 128;
113 }
114 else
115 {
116 bits = strtol(numbits, &endptr, 10);
117 if (*numbits == '\0' || *endptr != '\0')
118 return -1;
119 }
120
121 switch (family)
122 {
123 case AF_INET:
124 {
125 struct sockaddr_in mask4;
126 long maskl;
127
128 if (bits < 0 || bits > 32)
129 return -1;
130 memset(&mask4, 0, sizeof(mask4));
131 /* avoid "x << 32", which is not portable */
132 if (bits > 0)
133 maskl = (0xffffffffUL << (32 - (int) bits))
134 & 0xffffffffUL;
135 else
136 maskl = 0;
137 mask4.sin_addr.s_addr = pg_hton32(maskl);
138 memcpy(mask, &mask4, sizeof(mask4));
139 break;
140 }
141
142 case AF_INET6:
143 {
144 struct sockaddr_in6 mask6;
145 int i;
146
147 if (bits < 0 || bits > 128)
148 return -1;
149 memset(&mask6, 0, sizeof(mask6));
150 for (i = 0; i < 16; i++)
151 {
152 if (bits <= 0)
153 mask6.sin6_addr.s6_addr[i] = 0;
154 else if (bits >= 8)
155 mask6.sin6_addr.s6_addr[i] = 0xff;
156 else
157 {
158 mask6.sin6_addr.s6_addr[i] =
159 (0xff << (8 - (int) bits)) & 0xff;
160 }
161 bits -= 8;
162 }
163 memcpy(mask, &mask6, sizeof(mask6));
164 break;
165 }
166
167 default:
168 return -1;
169 }
170
171 mask->ss_family = family;
172 return 0;
173}
174
175
176/*
177 * Run the callback function for the addr/mask, after making sure the
178 * mask is sane for the addr.
179 */
180static void
182 struct sockaddr *addr, struct sockaddr *mask)
183{
184 struct sockaddr_storage fullmask;
185
186 if (!addr)
187 return;
188
189 /* Check that the mask is valid */
190 if (mask)
191 {
192 if (mask->sa_family != addr->sa_family)
193 {
194 mask = NULL;
195 }
196 else if (mask->sa_family == AF_INET)
197 {
198 if (((struct sockaddr_in *) mask)->sin_addr.s_addr == INADDR_ANY)
199 mask = NULL;
200 }
201 else if (mask->sa_family == AF_INET6)
202 {
203 if (IN6_IS_ADDR_UNSPECIFIED(&((struct sockaddr_in6 *) mask)->sin6_addr))
204 mask = NULL;
205 }
206 }
207
208 /* If mask is invalid, generate our own fully-set mask */
209 if (!mask)
210 {
211 pg_sockaddr_cidr_mask(&fullmask, NULL, addr->sa_family);
212 mask = (struct sockaddr *) &fullmask;
213 }
214
215 (*callback) (addr, mask, cb_data);
216}
217
218#ifdef WIN32
219
220#include <winsock2.h>
221#include <ws2tcpip.h>
222
223/*
224 * Enumerate the system's network interface addresses and call the callback
225 * for each one. Returns 0 if successful, -1 if trouble.
226 *
227 * This version is for Win32. Uses the Winsock 2 functions (ie: ws2_32.dll)
228 */
229int
231{
232 INTERFACE_INFO *ptr,
233 *ii = NULL;
234 unsigned long length,
235 i;
236 unsigned long n_ii = 0;
237 SOCKET sock;
238 int error;
239
240 sock = WSASocket(AF_INET, SOCK_DGRAM, 0, 0, 0, 0);
241 if (sock == INVALID_SOCKET)
242 return -1;
243
244 while (n_ii < 1024)
245 {
246 n_ii += 64;
247 ptr = realloc(ii, sizeof(INTERFACE_INFO) * n_ii);
248 if (!ptr)
249 {
250 free(ii);
251 closesocket(sock);
252 errno = ENOMEM;
253 return -1;
254 }
255
256 ii = ptr;
257 if (WSAIoctl(sock, SIO_GET_INTERFACE_LIST, 0, 0,
258 ii, n_ii * sizeof(INTERFACE_INFO),
259 &length, 0, 0) == SOCKET_ERROR)
260 {
261 error = WSAGetLastError();
262 if (error == WSAEFAULT || error == WSAENOBUFS)
263 continue; /* need to make the buffer bigger */
264 closesocket(sock);
265 free(ii);
266 return -1;
267 }
268
269 break;
270 }
271
272 for (i = 0; i < length / sizeof(INTERFACE_INFO); ++i)
274 (struct sockaddr *) &ii[i].iiAddress,
275 (struct sockaddr *) &ii[i].iiNetmask);
276
277 closesocket(sock);
278 free(ii);
279 return 0;
280}
281#elif HAVE_GETIFADDRS /* && !WIN32 */
282
283#ifdef HAVE_IFADDRS_H
284#include <ifaddrs.h>
285#endif
286
287/*
288 * Enumerate the system's network interface addresses and call the callback
289 * for each one. Returns 0 if successful, -1 if trouble.
290 *
291 * This version uses the getifaddrs() interface, which is available on
292 * BSDs, macOS, Solaris, illumos and Linux.
293 */
294int
296{
297 struct ifaddrs *ifa,
298 *l;
299
300 if (getifaddrs(&ifa) < 0)
301 return -1;
302
303 for (l = ifa; l; l = l->ifa_next)
305 l->ifa_addr, l->ifa_netmask);
306
307 freeifaddrs(ifa);
308 return 0;
309}
310#else /* !HAVE_GETIFADDRS && !WIN32 */
311
312#include <sys/ioctl.h>
313#include <net/if.h>
314
315#if defined(SIOCGIFCONF)
316
317/*
318 * Remaining Unixes use SIOCGIFCONF. Some only return IPv4 information
319 * here, so this is the least preferred method. Note that there is no
320 * standard way to iterate the struct ifreq returned in the array.
321 * On some OSs the structures are padded large enough for any address,
322 * on others you have to calculate the size of the struct ifreq.
323 */
324
325/* Some OSs have _SIZEOF_ADDR_IFREQ, so just use that */
326#ifndef _SIZEOF_ADDR_IFREQ
327
328/* Calculate based on sockaddr.sa_len */
329#ifdef HAVE_STRUCT_SOCKADDR_SA_LEN
330#define _SIZEOF_ADDR_IFREQ(ifr) \
331 ((ifr).ifr_addr.sa_len > sizeof(struct sockaddr) ? \
332 (sizeof(struct ifreq) - sizeof(struct sockaddr) + \
333 (ifr).ifr_addr.sa_len) : sizeof(struct ifreq))
334
335/* Padded ifreq structure, simple */
336#else
337#define _SIZEOF_ADDR_IFREQ(ifr) \
338 sizeof (struct ifreq)
339#endif
340#endif /* !_SIZEOF_ADDR_IFREQ */
341
342/*
343 * Enumerate the system's network interface addresses and call the callback
344 * for each one. Returns 0 if successful, -1 if trouble.
345 *
346 * This version uses ioctl(SIOCGIFCONF).
347 */
348int
350{
351 struct ifconf ifc;
352 struct ifreq *ifr,
353 *end,
354 addr,
355 mask;
356 char *ptr,
357 *buffer = NULL;
358 size_t n_buffer = 1024;
359 pgsocket sock;
360
361 sock = socket(AF_INET, SOCK_DGRAM, 0);
362 if (sock == PGINVALID_SOCKET)
363 return -1;
364
365 while (n_buffer < 1024 * 100)
366 {
367 n_buffer += 1024;
368 ptr = realloc(buffer, n_buffer);
369 if (!ptr)
370 {
371 free(buffer);
372 close(sock);
373 errno = ENOMEM;
374 return -1;
375 }
376
377 memset(&ifc, 0, sizeof(ifc));
378 ifc.ifc_buf = buffer = ptr;
379 ifc.ifc_len = n_buffer;
380
381 if (ioctl(sock, SIOCGIFCONF, &ifc) < 0)
382 {
383 if (errno == EINVAL)
384 continue;
385 free(buffer);
386 close(sock);
387 return -1;
388 }
389
390 /*
391 * Some Unixes try to return as much data as possible, with no
392 * indication of whether enough space allocated. Don't believe we have
393 * it all unless there's lots of slop.
394 */
395 if (ifc.ifc_len < n_buffer - 1024)
396 break;
397 }
398
399 end = (struct ifreq *) (buffer + ifc.ifc_len);
400 for (ifr = ifc.ifc_req; ifr < end;)
401 {
402 memcpy(&addr, ifr, sizeof(addr));
403 memcpy(&mask, ifr, sizeof(mask));
404 if (ioctl(sock, SIOCGIFADDR, &addr, sizeof(addr)) == 0 &&
405 ioctl(sock, SIOCGIFNETMASK, &mask, sizeof(mask)) == 0)
407 &addr.ifr_addr, &mask.ifr_addr);
408 ifr = (struct ifreq *) ((char *) ifr + _SIZEOF_ADDR_IFREQ(*ifr));
409 }
410
411 free(buffer);
412 close(sock);
413 return 0;
414}
415#else /* !defined(SIOCGIFCONF) */
416
417/*
418 * Enumerate the system's network interface addresses and call the callback
419 * for each one. Returns 0 if successful, -1 if trouble.
420 *
421 * This version is our fallback if there's no known way to get the
422 * interface addresses. Just return the standard loopback addresses.
423 */
424int
426{
427 struct sockaddr_in addr;
428 struct sockaddr_storage mask;
429 struct sockaddr_in6 addr6;
430
431 /* addr 127.0.0.1/8 */
432 memset(&addr, 0, sizeof(addr));
433 addr.sin_family = AF_INET;
434 addr.sin_addr.s_addr = pg_ntoh32(0x7f000001);
435 memset(&mask, 0, sizeof(mask));
436 pg_sockaddr_cidr_mask(&mask, "8", AF_INET);
438 (struct sockaddr *) &addr,
439 (struct sockaddr *) &mask);
440
441 /* addr ::1/128 */
442 memset(&addr6, 0, sizeof(addr6));
443 addr6.sin6_family = AF_INET6;
444 addr6.sin6_addr.s6_addr[15] = 1;
445 memset(&mask, 0, sizeof(mask));
446 pg_sockaddr_cidr_mask(&mask, "128", AF_INET6);
448 (struct sockaddr *) &addr6,
449 (struct sockaddr *) &mask);
450
451 return 0;
452}
453#endif /* !defined(SIOCGIFCONF) */
454
455#endif /* !HAVE_GETIFADDRS */
#define realloc(a, b)
Definition: header.h:60
#define free(a)
Definition: header.h:65
static int range_sockaddr_AF_INET6(const struct sockaddr_in6 *addr, const struct sockaddr_in6 *netaddr, const struct sockaddr_in6 *netmask)
Definition: ifaddr.c:78
int pg_sockaddr_cidr_mask(struct sockaddr_storage *mask, char *numbits, int family)
Definition: ifaddr.c:105
int pg_foreach_ifaddr(PgIfAddrCallback callback, void *cb_data)
Definition: ifaddr.c:425
static int range_sockaddr_AF_INET(const struct sockaddr_in *addr, const struct sockaddr_in *netaddr, const struct sockaddr_in *netmask)
Definition: ifaddr.c:66
static void run_ifaddr_callback(PgIfAddrCallback callback, void *cb_data, struct sockaddr *addr, struct sockaddr *mask)
Definition: ifaddr.c:181
int pg_range_sockaddr(const struct sockaddr_storage *addr, const struct sockaddr_storage *netaddr, const struct sockaddr_storage *netmask)
Definition: ifaddr.c:49
void(* PgIfAddrCallback)(struct sockaddr *addr, struct sockaddr *netmask, void *cb_data)
Definition: ifaddr.h:17
#define close(a)
Definition: win32.h:12
int i
Definition: isn.c:72
#define pg_ntoh32(x)
Definition: pg_bswap.h:125
#define pg_hton32(x)
Definition: pg_bswap.h:121
int pgsocket
Definition: port.h:29
#define PGINVALID_SOCKET
Definition: port.h:31
#define closesocket
Definition: port.h:377
static void error(void)
Definition: sql-dyntest.c:147
static void callback(struct sockaddr *addr, struct sockaddr *mask, void *unused)
Definition: test_ifaddrs.c:46
#define socket(af, type, protocol)
Definition: win32_port.h:498