Line data Source code
1 : /*-------------------------------------------------------------------------
2 : *
3 : * ip.c
4 : * IPv6-aware network access.
5 : *
6 : * Portions Copyright (c) 1996-2024, PostgreSQL Global Development Group
7 : * Portions Copyright (c) 1994, Regents of the University of California
8 : *
9 : *
10 : * IDENTIFICATION
11 : * src/common/ip.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 : #ifndef FRONTEND
21 : #include "postgres.h"
22 : #else
23 : #include "postgres_fe.h"
24 : #endif
25 :
26 : #include <unistd.h>
27 : #include <sys/stat.h>
28 : #include <sys/socket.h>
29 : #include <netdb.h>
30 : #include <netinet/in.h>
31 : #include <netinet/tcp.h>
32 : #include <arpa/inet.h>
33 : #include <sys/file.h>
34 :
35 : #include "common/ip.h"
36 :
37 :
38 :
39 : static int getaddrinfo_unix(const char *path,
40 : const struct addrinfo *hintsp,
41 : struct addrinfo **result);
42 :
43 : static int getnameinfo_unix(const struct sockaddr_un *sa, int salen,
44 : char *node, int nodelen,
45 : char *service, int servicelen,
46 : int flags);
47 :
48 :
49 : /*
50 : * pg_getaddrinfo_all - get address info for Unix, IPv4 and IPv6 sockets
51 : */
52 : int
53 30144 : pg_getaddrinfo_all(const char *hostname, const char *servname,
54 : const struct addrinfo *hintp, struct addrinfo **result)
55 : {
56 : int rc;
57 :
58 : /* not all versions of getaddrinfo() zero *result on failure */
59 30144 : *result = NULL;
60 :
61 30144 : if (hintp->ai_family == AF_UNIX)
62 23110 : return getaddrinfo_unix(servname, hintp, result);
63 :
64 : /* NULL has special meaning to getaddrinfo(). */
65 7034 : rc = getaddrinfo((!hostname || hostname[0] == '\0') ? NULL : hostname,
66 : servname, hintp, result);
67 :
68 7034 : return rc;
69 : }
70 :
71 :
72 : /*
73 : * pg_freeaddrinfo_all - free addrinfo structures for IPv4, IPv6, or Unix
74 : *
75 : * Note: the ai_family field of the original hint structure must be passed
76 : * so that we can tell whether the addrinfo struct was built by the system's
77 : * getaddrinfo() routine or our own getaddrinfo_unix() routine. Some versions
78 : * of getaddrinfo() might be willing to return AF_UNIX addresses, so it's
79 : * not safe to look at ai_family in the addrinfo itself.
80 : */
81 : void
82 30144 : pg_freeaddrinfo_all(int hint_ai_family, struct addrinfo *ai)
83 : {
84 30144 : if (hint_ai_family == AF_UNIX)
85 : {
86 : /* struct was built by getaddrinfo_unix (see pg_getaddrinfo_all) */
87 46220 : while (ai != NULL)
88 : {
89 23110 : struct addrinfo *p = ai;
90 :
91 23110 : ai = ai->ai_next;
92 23110 : free(p->ai_addr);
93 23110 : free(p);
94 : }
95 : }
96 : else
97 : {
98 : /* struct was built by getaddrinfo() */
99 7034 : if (ai != NULL)
100 7034 : freeaddrinfo(ai);
101 : }
102 30144 : }
103 :
104 :
105 : /*
106 : * pg_getnameinfo_all - get name info for Unix, IPv4 and IPv6 sockets
107 : *
108 : * The API of this routine differs from the standard getnameinfo() definition
109 : * in two ways: first, the addr parameter is declared as sockaddr_storage
110 : * rather than struct sockaddr, and second, the node and service fields are
111 : * guaranteed to be filled with something even on failure return.
112 : */
113 : int
114 43076 : pg_getnameinfo_all(const struct sockaddr_storage *addr, int salen,
115 : char *node, int nodelen,
116 : char *service, int servicelen,
117 : int flags)
118 : {
119 : int rc;
120 :
121 43076 : if (addr && addr->ss_family == AF_UNIX)
122 42440 : rc = getnameinfo_unix((const struct sockaddr_un *) addr, salen,
123 : node, nodelen,
124 : service, servicelen,
125 : flags);
126 : else
127 636 : rc = getnameinfo((const struct sockaddr *) addr, salen,
128 : node, nodelen,
129 : service, servicelen,
130 : flags);
131 :
132 43076 : if (rc != 0)
133 : {
134 0 : if (node)
135 0 : strlcpy(node, "???", nodelen);
136 0 : if (service)
137 0 : strlcpy(service, "???", servicelen);
138 : }
139 :
140 43076 : return rc;
141 : }
142 :
143 :
144 : /* -------
145 : * getaddrinfo_unix - get unix socket info using IPv6-compatible API
146 : *
147 : * Bugs: only one addrinfo is set even though hintsp is NULL or
148 : * ai_socktype is 0
149 : * AI_CANONNAME is not supported.
150 : * -------
151 : */
152 : static int
153 23110 : getaddrinfo_unix(const char *path, const struct addrinfo *hintsp,
154 : struct addrinfo **result)
155 : {
156 23110 : struct addrinfo hints = {0};
157 : struct addrinfo *aip;
158 : struct sockaddr_un *unp;
159 :
160 23110 : *result = NULL;
161 :
162 23110 : if (strlen(path) >= sizeof(unp->sun_path))
163 0 : return EAI_FAIL;
164 :
165 23110 : if (hintsp == NULL)
166 : {
167 0 : hints.ai_family = AF_UNIX;
168 0 : hints.ai_socktype = SOCK_STREAM;
169 : }
170 : else
171 23110 : memcpy(&hints, hintsp, sizeof(hints));
172 :
173 23110 : if (hints.ai_socktype == 0)
174 0 : hints.ai_socktype = SOCK_STREAM;
175 :
176 23110 : if (hints.ai_family != AF_UNIX)
177 : {
178 : /* shouldn't have been called */
179 0 : return EAI_FAIL;
180 : }
181 :
182 23110 : aip = calloc(1, sizeof(struct addrinfo));
183 23110 : if (aip == NULL)
184 0 : return EAI_MEMORY;
185 :
186 23110 : unp = calloc(1, sizeof(struct sockaddr_un));
187 23110 : if (unp == NULL)
188 : {
189 0 : free(aip);
190 0 : return EAI_MEMORY;
191 : }
192 :
193 23110 : aip->ai_family = AF_UNIX;
194 23110 : aip->ai_socktype = hints.ai_socktype;
195 23110 : aip->ai_protocol = hints.ai_protocol;
196 23110 : aip->ai_next = NULL;
197 23110 : aip->ai_canonname = NULL;
198 23110 : *result = aip;
199 :
200 23110 : unp->sun_family = AF_UNIX;
201 23110 : aip->ai_addr = (struct sockaddr *) unp;
202 23110 : aip->ai_addrlen = sizeof(struct sockaddr_un);
203 :
204 23110 : strcpy(unp->sun_path, path);
205 :
206 : /*
207 : * If the supplied path starts with @, replace that with a zero byte for
208 : * the internal representation. In that mode, the entire sun_path is the
209 : * address, including trailing zero bytes. But we set the address length
210 : * to only include the length of the original string. That way the
211 : * trailing zero bytes won't show up in any network or socket lists of the
212 : * operating system. This is just a convention, also followed by other
213 : * packages.
214 : */
215 23110 : if (path[0] == '@')
216 : {
217 0 : unp->sun_path[0] = '\0';
218 0 : aip->ai_addrlen = offsetof(struct sockaddr_un, sun_path) + strlen(path);
219 : }
220 :
221 23110 : return 0;
222 : }
223 :
224 : /*
225 : * Convert an address to a hostname.
226 : */
227 : static int
228 42440 : getnameinfo_unix(const struct sockaddr_un *sa, int salen,
229 : char *node, int nodelen,
230 : char *service, int servicelen,
231 : int flags)
232 : {
233 : int ret;
234 :
235 : /* Invalid arguments. */
236 42440 : if (sa == NULL || sa->sun_family != AF_UNIX ||
237 21700 : (node == NULL && service == NULL))
238 0 : return EAI_FAIL;
239 :
240 42440 : if (node)
241 : {
242 20740 : ret = snprintf(node, nodelen, "%s", "[local]");
243 20740 : if (ret < 0 || ret >= nodelen)
244 0 : return EAI_MEMORY;
245 : }
246 :
247 42440 : if (service)
248 : {
249 : /*
250 : * Check whether it looks like an abstract socket, but it could also
251 : * just be an empty string.
252 : */
253 42426 : if (sa->sun_path[0] == '\0' && sa->sun_path[1] != '\0')
254 0 : ret = snprintf(service, servicelen, "@%s", sa->sun_path + 1);
255 : else
256 42426 : ret = snprintf(service, servicelen, "%s", sa->sun_path);
257 42426 : if (ret < 0 || ret >= servicelen)
258 0 : return EAI_MEMORY;
259 : }
260 :
261 42440 : return 0;
262 : }
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