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/backend/utils/adt/inet_net_ntop.c
18 */
19
20 #if defined(LIBC_SCCS) && !defined(lint)
21 static const char rcsid[] = "Id: inet_net_ntop.c,v 1.1.2.2 2004/03/09 09:17:27 marka Exp $";
22 #endif
23
24 #include "postgres.h"
25
26 #include <sys/types.h>
27 #include <sys/socket.h>
28 #include <netinet/in.h>
29 #include <arpa/inet.h>
30
31 #include "utils/builtins.h"
32 #include "utils/inet.h"
33
34
35 #ifdef SPRINTF_CHAR
36 #define SPRINTF(x) strlen(sprintf/**/x)
37 #else
38 #define SPRINTF(x) ((size_t)sprintf x)
39 #endif
40
41 static char *inet_cidr_ntop_ipv4(const u_char *src, int bits,
42 char *dst, size_t size);
43 static char *inet_cidr_ntop_ipv6(const u_char *src, int bits,
44 char *dst, size_t size);
45
46 /*
47 * char *
48 * inet_cidr_ntop(af, src, bits, dst, size)
49 * convert network number from network to presentation format.
50 * generates CIDR style result always.
51 * return:
52 * pointer to dst, or NULL if an error occurred (check errno).
53 * author:
54 * Paul Vixie (ISC), July 1996
55 */
56 char *
inet_cidr_ntop(int af,const void * src,int bits,char * dst,size_t size)57 inet_cidr_ntop(int af, const void *src, int bits, char *dst, size_t size)
58 {
59 switch (af)
60 {
61 case PGSQL_AF_INET:
62 return (inet_cidr_ntop_ipv4(src, bits, dst, size));
63 case PGSQL_AF_INET6:
64 return (inet_cidr_ntop_ipv6(src, bits, dst, size));
65 default:
66 errno = EAFNOSUPPORT;
67 return (NULL);
68 }
69 }
70
71
72 /*
73 * static char *
74 * inet_cidr_ntop_ipv4(src, bits, dst, size)
75 * convert IPv4 network number from network to presentation format.
76 * generates CIDR style result always.
77 * return:
78 * pointer to dst, or NULL if an error occurred (check errno).
79 * note:
80 * network byte order assumed. this means 192.5.5.240/28 has
81 * 0b11110000 in its fourth octet.
82 * author:
83 * Paul Vixie (ISC), July 1996
84 */
85 static char *
inet_cidr_ntop_ipv4(const u_char * src,int bits,char * dst,size_t size)86 inet_cidr_ntop_ipv4(const u_char *src, int bits, char *dst, size_t size)
87 {
88 char *odst = dst;
89 char *t;
90 u_int m;
91 int b;
92
93 if (bits < 0 || bits > 32)
94 {
95 errno = EINVAL;
96 return (NULL);
97 }
98
99 if (bits == 0)
100 {
101 if (size < sizeof "0")
102 goto emsgsize;
103 *dst++ = '0';
104 size--;
105 *dst = '\0';
106 }
107
108 /* Format whole octets. */
109 for (b = bits / 8; b > 0; b--)
110 {
111 if (size <= sizeof "255.")
112 goto emsgsize;
113 t = dst;
114 dst += SPRINTF((dst, "%u", *src++));
115 if (b > 1)
116 {
117 *dst++ = '.';
118 *dst = '\0';
119 }
120 size -= (size_t) (dst - t);
121 }
122
123 /* Format partial octet. */
124 b = bits % 8;
125 if (b > 0)
126 {
127 if (size <= sizeof ".255")
128 goto emsgsize;
129 t = dst;
130 if (dst != odst)
131 *dst++ = '.';
132 m = ((1 << b) - 1) << (8 - b);
133 dst += SPRINTF((dst, "%u", *src & m));
134 size -= (size_t) (dst - t);
135 }
136
137 /* Format CIDR /width. */
138 if (size <= sizeof "/32")
139 goto emsgsize;
140 dst += SPRINTF((dst, "/%u", bits));
141 return (odst);
142
143 emsgsize:
144 errno = EMSGSIZE;
145 return (NULL);
146 }
147
148 /*
149 * static char *
150 * inet_cidr_ntop_ipv6(src, bits, fakebits, dst, size)
151 * convert IPv6 network number from network to presentation format.
152 * generates CIDR style result always. Picks the shortest representation
153 * unless the IP is really IPv4.
154 * always prints specified number of bits (bits).
155 * return:
156 * pointer to dst, or NULL if an error occurred (check errno).
157 * note:
158 * network byte order assumed. this means 192.5.5.240/28 has
159 * 0x11110000 in its fourth octet.
160 * author:
161 * Vadim Kogan (UCB), June 2001
162 * Original version (IPv4) by Paul Vixie (ISC), July 1996
163 */
164
165 static char *
inet_cidr_ntop_ipv6(const u_char * src,int bits,char * dst,size_t size)166 inet_cidr_ntop_ipv6(const u_char *src, int bits, char *dst, size_t size)
167 {
168 u_int m;
169 int b;
170 int p;
171 int zero_s,
172 zero_l,
173 tmp_zero_s,
174 tmp_zero_l;
175 int i;
176 int is_ipv4 = 0;
177 unsigned char inbuf[16];
178 char outbuf[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255/128")];
179 char *cp;
180 int words;
181 u_char *s;
182
183 if (bits < 0 || bits > 128)
184 {
185 errno = EINVAL;
186 return (NULL);
187 }
188
189 cp = outbuf;
190
191 if (bits == 0)
192 {
193 *cp++ = ':';
194 *cp++ = ':';
195 *cp = '\0';
196 }
197 else
198 {
199 /* Copy src to private buffer. Zero host part. */
200 p = (bits + 7) / 8;
201 memcpy(inbuf, src, p);
202 memset(inbuf + p, 0, 16 - p);
203 b = bits % 8;
204 if (b != 0)
205 {
206 m = ~0 << (8 - b);
207 inbuf[p - 1] &= m;
208 }
209
210 s = inbuf;
211
212 /* how many words need to be displayed in output */
213 words = (bits + 15) / 16;
214 if (words == 1)
215 words = 2;
216
217 /* Find the longest substring of zero's */
218 zero_s = zero_l = tmp_zero_s = tmp_zero_l = 0;
219 for (i = 0; i < (words * 2); i += 2)
220 {
221 if ((s[i] | s[i + 1]) == 0)
222 {
223 if (tmp_zero_l == 0)
224 tmp_zero_s = i / 2;
225 tmp_zero_l++;
226 }
227 else
228 {
229 if (tmp_zero_l && zero_l < tmp_zero_l)
230 {
231 zero_s = tmp_zero_s;
232 zero_l = tmp_zero_l;
233 tmp_zero_l = 0;
234 }
235 }
236 }
237
238 if (tmp_zero_l && zero_l < tmp_zero_l)
239 {
240 zero_s = tmp_zero_s;
241 zero_l = tmp_zero_l;
242 }
243
244 if (zero_l != words && zero_s == 0 && ((zero_l == 6) ||
245 ((zero_l == 5 && s[10] == 0xff && s[11] == 0xff) ||
246 ((zero_l == 7 && s[14] != 0 && s[15] != 1)))))
247 is_ipv4 = 1;
248
249 /* Format whole words. */
250 for (p = 0; p < words; p++)
251 {
252 if (zero_l != 0 && p >= zero_s && p < zero_s + zero_l)
253 {
254 /* Time to skip some zeros */
255 if (p == zero_s)
256 *cp++ = ':';
257 if (p == words - 1)
258 *cp++ = ':';
259 s++;
260 s++;
261 continue;
262 }
263
264 if (is_ipv4 && p > 5)
265 {
266 *cp++ = (p == 6) ? ':' : '.';
267 cp += SPRINTF((cp, "%u", *s++));
268 /* we can potentially drop the last octet */
269 if (p != 7 || bits > 120)
270 {
271 *cp++ = '.';
272 cp += SPRINTF((cp, "%u", *s++));
273 }
274 }
275 else
276 {
277 if (cp != outbuf)
278 *cp++ = ':';
279 cp += SPRINTF((cp, "%x", *s * 256 + s[1]));
280 s += 2;
281 }
282 }
283 }
284 /* Format CIDR /width. */
285 (void) SPRINTF((cp, "/%u", bits));
286 if (strlen(outbuf) + 1 > size)
287 goto emsgsize;
288 strcpy(dst, outbuf);
289
290 return (dst);
291
292 emsgsize:
293 errno = EMSGSIZE;
294 return (NULL);
295 }
296