1 /** @File
2 Convert a binary network address into a presentable (printable) format.
3
4 Copyright (c) 2011, Intel Corporation. All rights reserved.<BR>
5 This program and the accompanying materials are licensed and made available under
6 the terms and conditions of the BSD License that accompanies this distribution.
7 The full text of the license may be found at
8 http://opensource.org/licenses/bsd-license.
9
10 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
11 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
12
13 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
14 * Copyright (c) 1996-1999 by Internet Software Consortium.
15 *
16 * Permission to use, copy, modify, and distribute this software for any
17 * purpose with or without fee is hereby granted, provided that the above
18 * copyright notice and this permission notice appear in all copies.
19 *
20 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
21 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
22 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR
23 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
24 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
25 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
26 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
27
28 NetBSD: inet_ntop.c,v 1.3.4.2 2007/05/17 21:25:14 jdc Exp
29 inet_ntop.c,v 1.3.18.2 2005/11/03 23:02:22 marka Exp
30 **/
31 #include <LibConfig.h>
32
33 //#include "port_before.h"
34
35 #include "namespace.h"
36 #include <sys/param.h>
37 #include <sys/types.h>
38 #include <sys/socket.h>
39
40 #include <netinet/in.h>
41 #include <arpa/inet.h>
42 #include <arpa/nameser.h>
43
44 #include <assert.h>
45 #include <errno.h>
46 #include <stdio.h>
47 #include <stdlib.h>
48 #include <string.h>
49
50 //#include "port_after.h"
51
52 #ifdef __weak_alias
53 __weak_alias(inet_ntop,_inet_ntop)
54 #endif
55
56 /*%
57 * WARNING: Don't even consider trying to compile this on a system where
58 * sizeof(int) < 4. sizeof(int) > 4 is fine; all the world's not a VAX.
59 */
60
61 static const char *inet_ntop4(const u_char *src, char *dst, socklen_t size);
62 static const char *inet_ntop6(const u_char *src, char *dst, socklen_t size);
63
64 /* char *
65 * inet_ntop(af, src, dst, size)
66 * convert a network format address to presentation format.
67 * return:
68 * pointer to presentation format address (`dst'), or NULL (see errno).
69 * author:
70 * Paul Vixie, 1996.
71 */
72 const char *
inet_ntop(int af,const void * src,char * dst,socklen_t size)73 inet_ntop(int af, const void *src, char *dst, socklen_t size)
74 {
75
76 _DIAGASSERT(src != NULL);
77 _DIAGASSERT(dst != NULL);
78
79 switch (af) {
80 case AF_INET:
81 return (inet_ntop4(src, dst, size));
82 case AF_INET6:
83 return (inet_ntop6(src, dst, size));
84 default:
85 errno = EAFNOSUPPORT;
86 return (NULL);
87 }
88 /* NOTREACHED */
89 }
90
91 /* const char *
92 * inet_ntop4(src, dst, size)
93 * format an IPv4 address, more or less like inet_ntoa()
94 * return:
95 * `dst' (as a const)
96 * notes:
97 * (1) uses no statics
98 * (2) takes a u_char* not an in_addr as input
99 * author:
100 * Paul Vixie, 1996.
101 */
102 static const char *
inet_ntop4(const u_char * src,char * dst,socklen_t size)103 inet_ntop4(const u_char *src, char *dst, socklen_t size)
104 {
105 char tmp[sizeof "255.255.255.255"];
106 int l;
107
108 _DIAGASSERT(src != NULL);
109 _DIAGASSERT(dst != NULL);
110
111 l = snprintf(tmp, sizeof(tmp), "%u.%u.%u.%u",
112 src[0], src[1], src[2], src[3]);
113 if (l <= 0 || (socklen_t) l >= size) {
114 errno = ENOSPC;
115 return (NULL);
116 }
117 //strlcpy(dst, tmp, size);
118 strncpyX(dst, tmp, (size_t)size);
119 return (dst);
120 }
121
122 /* const char *
123 * inet_ntop6(src, dst, size)
124 * convert IPv6 binary address into presentation (printable) format
125 * author:
126 * Paul Vixie, 1996.
127 */
128 static const char *
inet_ntop6(const u_char * src,char * dst,socklen_t size)129 inet_ntop6(const u_char *src, char *dst, socklen_t size)
130 {
131 /*
132 * Note that int32_t and int16_t need only be "at least" large enough
133 * to contain a value of the specified size. On some systems, like
134 * Crays, there is no such thing as an integer variable with 16 bits.
135 * Keep this in mind if you think this function should have been coded
136 * to use pointer overlays. All the world's not a VAX.
137 */
138 char tmp[sizeof "ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255"];
139 char *tp, *ep;
140 struct { int base, len; } best, cur;
141 unsigned int words[NS_IN6ADDRSZ / NS_INT16SZ];
142 int i;
143 int advance;
144
145 _DIAGASSERT(src != NULL);
146 _DIAGASSERT(dst != NULL);
147
148 /*
149 * Preprocess:
150 * Copy the input (bytewise) array into a wordwise array.
151 * Find the longest run of 0x00's in src[] for :: shorthanding.
152 */
153 memset(words, '\0', sizeof words);
154 for (i = 0; i < NS_IN6ADDRSZ; i++)
155 words[i / 2] |= (src[i] << ((1 - (i % 2)) << 3));
156 best.base = -1;
157 best.len = 0;
158 cur.base = -1;
159 cur.len = 0;
160 for (i = 0; i < (NS_IN6ADDRSZ / NS_INT16SZ); i++) {
161 if (words[i] == 0) {
162 if (cur.base == -1)
163 cur.base = i, cur.len = 1;
164 else
165 cur.len++;
166 } else {
167 if (cur.base != -1) {
168 if (best.base == -1 || cur.len > best.len)
169 best = cur;
170 cur.base = -1;
171 }
172 }
173 }
174 if (cur.base != -1) {
175 if (best.base == -1 || cur.len > best.len)
176 best = cur;
177 }
178 if (best.base != -1 && best.len < 2)
179 best.base = -1;
180
181 /*
182 * Format the result.
183 */
184 tp = tmp;
185 ep = tmp + sizeof(tmp);
186 for (i = 0; i < (NS_IN6ADDRSZ / NS_INT16SZ); i++) {
187 /* Are we inside the best run of 0x00's? */
188 if (best.base != -1 && i >= best.base &&
189 i < (best.base + best.len)) {
190 if (i == best.base)
191 *tp++ = ':';
192 continue;
193 }
194 /* Are we following an initial run of 0x00s or any real hex? */
195 if (i != 0) {
196 if (tp + 1 >= ep)
197 return (NULL);
198 *tp++ = ':';
199 }
200 /* Is this address an encapsulated IPv4? */
201 if (i == 6 && best.base == 0 &&
202 (best.len == 6 ||
203 (best.len == 7 && words[7] != 0x0001) ||
204 (best.len == 5 && words[5] == 0xffff))) {
205 if (!inet_ntop4(src+12, tp, (socklen_t)(ep - tp)))
206 return (NULL);
207 tp += strlen(tp);
208 break;
209 }
210 advance = snprintf(tp, (size_t)(ep - tp), "%x", words[i]);
211 if (advance <= 0 || advance >= ep - tp)
212 return (NULL);
213 tp += advance;
214 }
215 /* Was it a trailing run of 0x00's? */
216 if (best.base != -1 && (best.base + best.len) ==
217 (NS_IN6ADDRSZ / NS_INT16SZ)) {
218 if (tp + 1 >= ep)
219 return (NULL);
220 *tp++ = ':';
221 }
222 if (tp + 1 >= ep)
223 return (NULL);
224 *tp++ = '\0';
225
226 /*
227 * Check for overflow, copy, and we're done.
228 */
229 if ((size_t)(tp - tmp) > size) {
230 errno = ENOSPC;
231 return (NULL);
232 }
233 //strlcpy(dst, tmp, size);
234 strncpyX(dst, tmp, (size_t)size);
235 return (dst);
236 }
237
238 /*! \file */
239