PostgreSQL Source Code: src/port/inet_net_ntop.c Source File

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inet_net_ntop.c
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1/*
2 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
3 * Copyright (c) 1996,1999 by Internet Software Consortium.
4 *
5 * Permission to use, copy, modify, and distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
8 *
9 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR
12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
15 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16 *
17 * src/port/inet_net_ntop.c
18 */
19
20#if defined(LIBC_SCCS) && !defined(lint)
21static const char rcsid[] = "Id: inet_net_ntop.c,v 1.1.2.2 2004年03月09日 09:17:27 marka Exp $";
22#endif
23
24#ifndef FRONTEND
25#include "postgres.h"
26#else
27#include "postgres_fe.h"
28#endif
29
30#include <sys/socket.h>
31#include <netinet/in.h>
32#include <arpa/inet.h>
33
34#ifndef FRONTEND
35#include "utils/inet.h"
36#else
37/*
38 * In a frontend build, we can't include inet.h, but we still need to have
39 * sensible definitions of these two constants. Note that pg_inet_net_ntop()
40 * assumes that PGSQL_AF_INET is equal to AF_INET.
41 */
42#define PGSQL_AF_INET (AF_INET + 0)
43#define PGSQL_AF_INET6 (AF_INET + 1)
44#endif
45
46
47 #define NS_IN6ADDRSZ 16
48 #define NS_INT16SZ 2
49
50#ifdef SPRINTF_CHAR
51#define SPRINTF(x) strlen(sprintfx)
52#else
53 #define SPRINTF(x) ((size_t)sprintf x)
54#endif
55
56static char *inet_net_ntop_ipv4(const u_char *src, int bits,
57 char *dst, size_t size);
58static char *inet_net_ntop_ipv6(const u_char *src, int bits,
59 char *dst, size_t size);
60
61
62/*
63 * char *
64 * pg_inet_net_ntop(af, src, bits, dst, size)
65 * convert host/network address from network to presentation format.
66 * "src"'s size is determined from its "af".
67 * return:
68 * pointer to dst, or NULL if an error occurred (check errno).
69 * note:
70 * 192.5.5.1/28 has a nonzero host part, which means it isn't a network
71 * as called for by pg_inet_net_pton() but it can be a host address with
72 * an included netmask.
73 * author:
74 * Paul Vixie (ISC), October 1998
75 */
76char *
77 pg_inet_net_ntop(int af, const void *src, int bits, char *dst, size_t size)
78{
79 /*
80 * We need to cover both the address family constants used by the PG inet
81 * type (PGSQL_AF_INET and PGSQL_AF_INET6) and those used by the system
82 * libraries (AF_INET and AF_INET6). We can safely assume PGSQL_AF_INET
83 * == AF_INET, but the INET6 constants are very likely to be different.
84 */
85 switch (af)
86 {
87 case PGSQL_AF_INET:
88 return (inet_net_ntop_ipv4(src, bits, dst, size));
89 case PGSQL_AF_INET6:
90#if AF_INET6 != PGSQL_AF_INET6
91 case AF_INET6:
92#endif
93 return (inet_net_ntop_ipv6(src, bits, dst, size));
94 default:
95 errno = EAFNOSUPPORT;
96 return (NULL);
97 }
98}
99
100/*
101 * static char *
102 * inet_net_ntop_ipv4(src, bits, dst, size)
103 * convert IPv4 network address from network to presentation format.
104 * "src"'s size is determined from its "af".
105 * return:
106 * pointer to dst, or NULL if an error occurred (check errno).
107 * note:
108 * network byte order assumed. this means 192.5.5.240/28 has
109 * 0b11110000 in its fourth octet.
110 * author:
111 * Paul Vixie (ISC), October 1998
112 */
113static char *
114 inet_net_ntop_ipv4(const u_char *src, int bits, char *dst, size_t size)
115{
116 char *odst = dst;
117 char *t;
118 int len = 4;
119 int b;
120
121 if (bits < 0 || bits > 32)
122 {
123 errno = EINVAL;
124 return (NULL);
125 }
126
127 /* Always format all four octets, regardless of mask length. */
128 for (b = len; b > 0; b--)
129 {
130 if (size <= sizeof ".255")
131 goto emsgsize;
132 t = dst;
133 if (dst != odst)
134 *dst++ = '.';
135 dst += SPRINTF((dst, "%u", *src++));
136 size -= (size_t) (dst - t);
137 }
138
139 /* don't print masklen if 32 bits */
140 if (bits != 32)
141 {
142 if (size <= sizeof "/32")
143 goto emsgsize;
144 dst += SPRINTF((dst, "/%u", bits));
145 }
146
147 return (odst);
148
149emsgsize:
150 errno = EMSGSIZE;
151 return (NULL);
152}
153
154static int
155 decoct(const u_char *src, int bytes, char *dst, size_t size)
156{
157 char *odst = dst;
158 char *t;
159 int b;
160
161 for (b = 1; b <= bytes; b++)
162 {
163 if (size <= sizeof "255.")
164 return (0);
165 t = dst;
166 dst += SPRINTF((dst, "%u", *src++));
167 if (b != bytes)
168 {
169 *dst++ = '.';
170 *dst = '0円';
171 }
172 size -= (size_t) (dst - t);
173 }
174 return (dst - odst);
175}
176
177static char *
178 inet_net_ntop_ipv6(const u_char *src, int bits, char *dst, size_t size)
179{
180 /*
181 * Note that int32_t and int16_t need only be "at least" large enough to
182 * contain a value of the specified size. On some systems, like Crays,
183 * there is no such thing as an integer variable with 16 bits. Keep this
184 * in mind if you think this function should have been coded to use
185 * pointer overlays. All the world's not a VAX.
186 */
187 char tmp[sizeof "ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255/128"];
188 char *tp;
189 struct
190 {
191 int base,
192 len;
193 } best, cur;
194 u_int words[NS_IN6ADDRSZ / NS_INT16SZ];
195 int i;
196
197 if ((bits < -1) || (bits > 128))
198 {
199 errno = EINVAL;
200 return (NULL);
201 }
202
203 /*
204 * Preprocess: Copy the input (bytewise) array into a wordwise array. Find
205 * the longest run of 0x00's in src[] for :: shorthanding.
206 */
207 memset(words, '0円', sizeof words);
208 for (i = 0; i < NS_IN6ADDRSZ; i++)
209 words[i / 2] |= (src[i] << ((1 - (i % 2)) << 3));
210 best.base = -1;
211 cur.base = -1;
212 best.len = 0;
213 cur.len = 0;
214 for (i = 0; i < (NS_IN6ADDRSZ / NS_INT16SZ); i++)
215 {
216 if (words[i] == 0)
217 {
218 if (cur.base == -1)
219 cur.base = i, cur.len = 1;
220 else
221 cur.len++;
222 }
223 else
224 {
225 if (cur.base != -1)
226 {
227 if (best.base == -1 || cur.len > best.len)
228 best = cur;
229 cur.base = -1;
230 }
231 }
232 }
233 if (cur.base != -1)
234 {
235 if (best.base == -1 || cur.len > best.len)
236 best = cur;
237 }
238 if (best.base != -1 && best.len < 2)
239 best.base = -1;
240
241 /*
242 * Format the result.
243 */
244 tp = tmp;
245 for (i = 0; i < (NS_IN6ADDRSZ / NS_INT16SZ); i++)
246 {
247 /* Are we inside the best run of 0x00's? */
248 if (best.base != -1 && i >= best.base &&
249 i < (best.base + best.len))
250 {
251 if (i == best.base)
252 *tp++ = ':';
253 continue;
254 }
255 /* Are we following an initial run of 0x00s or any real hex? */
256 if (i != 0)
257 *tp++ = ':';
258 /* Is this address an encapsulated IPv4? */
259 if (i == 6 && best.base == 0 && (best.len == 6 ||
260 (best.len == 7 && words[7] != 0x0001) ||
261 (best.len == 5 && words[5] == 0xffff)))
262 {
263 int n;
264
265 n = decoct(src + 12, 4, tp, sizeof tmp - (tp - tmp));
266 if (n == 0)
267 {
268 errno = EMSGSIZE;
269 return (NULL);
270 }
271 tp += strlen(tp);
272 break;
273 }
274 tp += SPRINTF((tp, "%x", words[i]));
275 }
276
277 /* Was it a trailing run of 0x00's? */
278 if (best.base != -1 && (best.base + best.len) ==
279 (NS_IN6ADDRSZ / NS_INT16SZ))
280 *tp++ = ':';
281 *tp = '0円';
282
283 if (bits != -1 && bits != 128)
284 tp += SPRINTF((tp, "/%u", bits));
285
286 /*
287 * Check for overflow, copy, and we're done.
288 */
289 if ((size_t) (tp - tmp) > size)
290 {
291 errno = EMSGSIZE;
292 return (NULL);
293 }
294 strcpy(dst, tmp);
295 return (dst);
296}
struct cursor * cur
Definition: ecpg.c:29
static char * inet_net_ntop_ipv6(const u_char *src, int bits, char *dst, size_t size)
Definition: inet_net_ntop.c:178
char * pg_inet_net_ntop(int af, const void *src, int bits, char *dst, size_t size)
Definition: inet_net_ntop.c:77
#define NS_IN6ADDRSZ
Definition: inet_net_ntop.c:47
#define NS_INT16SZ
Definition: inet_net_ntop.c:48
#define SPRINTF(x)
Definition: inet_net_ntop.c:53
static char * inet_net_ntop_ipv4(const u_char *src, int bits, char *dst, size_t size)
Definition: inet_net_ntop.c:114
static int decoct(const u_char *src, int bytes, char *dst, size_t size)
Definition: inet_net_ntop.c:155
b
int b
Definition: isn.c:74
i
int i
Definition: isn.c:77
const void size_t len
#define PGSQL_AF_INET
Definition: inet.h:39
#define PGSQL_AF_INET6
Definition: inet.h:40
#define EAFNOSUPPORT
Definition: win32_port.h:368
#define EMSGSIZE
Definition: win32_port.h:366

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