1 /*
2 * Copyright (C) 2004, 2005, 2007 Internet Systems Consortium, Inc. ("ISC")
3 * Copyright (C) 1996-2003 Internet Software Consortium.
4 *
5 * Permission to use, copy, modify, and/or 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 WITH
10 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
11 * AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
12 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
13 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
14 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
15 * PERFORMANCE OF THIS SOFTWARE.
16 */
17
18 /*! \file */
19
20 #if defined(LIBC_SCCS) && !defined(lint)
21 static char rcsid[] =
22 "$Id: inet_pton.c,v 1.19 2007/06/19 23:47:17 tbox Exp $";
23 #endif /* LIBC_SCCS and not lint */
24
25 #include <config.h>
26
27 #include <errno.h>
28 #include <string.h>
29
30 #include <isc/net.h>
31
32 /*% INT16 Size */
33 #define NS_INT16SZ 2
34 /*% IPv4 Address Size */
35 #define NS_INADDRSZ 4
36 /*% IPv6 Address Size */
37 #define NS_IN6ADDRSZ 16
38
39 /*
40 * WARNING: Don't even consider trying to compile this on a system where
41 * sizeof(int) < 4. sizeof(int) > 4 is fine; all the world's not a VAX.
42 */
43
44 static int inet_pton4(const char *src, unsigned char *dst);
45 static int inet_pton6(const char *src, unsigned char *dst);
46 int isc_net_pton(int af, const char *src, void *dst);
47
48 /*%
49 * convert from presentation format (which usually means ASCII printable)
50 * to network format (which is usually some kind of binary format).
51 * \return
52 * 1 if the address was valid for the specified address family
53 * 0 if the address wasn't valid (`dst' is untouched in this case)
54 * -1 if some other error occurred (`dst' is untouched in this case, too)
55 * \author
56 * Paul Vixie, 1996.
57 */
58 int
isc_net_pton(int af,const char * src,void * dst)59 isc_net_pton(int af, const char *src, void *dst) {
60 switch (af) {
61 case AF_INET:
62 return (inet_pton4(src, dst));
63 case AF_INET6:
64 return (inet_pton6(src, dst));
65 default:
66 errno = EAFNOSUPPORT;
67 return (-1);
68 }
69 /* NOTREACHED */
70 }
71
72 /*!\fn static int inet_pton4(const char *src, unsigned char *dst)
73 * \brief
74 * like inet_aton() but without all the hexadecimal and shorthand.
75 * \return
76 * 1 if `src' is a valid dotted quad, else 0.
77 * \note
78 * does not touch `dst' unless it's returning 1.
79 * \author
80 * Paul Vixie, 1996.
81 */
82 static int
inet_pton4(const char * src,unsigned char * dst)83 inet_pton4(const char *src, unsigned char *dst) {
84 static const char digits[] = "0123456789";
85 int saw_digit, octets, ch;
86 unsigned char tmp[NS_INADDRSZ], *tp;
87
88 saw_digit = 0;
89 octets = 0;
90 *(tp = tmp) = 0;
91 while ((ch = *src++) != '\0') {
92 const char *pch;
93
94 if ((pch = strchr(digits, ch)) != NULL) {
95 size_t newv = *tp * 10 + (pch - digits);
96
97 if (saw_digit && *tp == 0)
98 return (0);
99 if (newv > 255)
100 return (0);
101 *tp = (unsigned char)newv;
102 if (!saw_digit) {
103 if (++octets > 4)
104 return (0);
105 saw_digit = 1;
106 }
107 } else if (ch == '.' && saw_digit) {
108 if (octets == 4)
109 return (0);
110 *++tp = 0;
111 saw_digit = 0;
112 } else
113 return (0);
114 }
115 if (octets < 4)
116 return (0);
117 memcpy(dst, tmp, NS_INADDRSZ);
118 return (1);
119 }
120
121 /*%
122 * convert presentation level address to network order binary form.
123 * \return
124 * 1 if `src' is a valid [RFC1884 2.2] address, else 0.
125 * \note
126 * (1) does not touch `dst' unless it's returning 1.
127 * \note
128 * (2) :: in a full address is silently ignored.
129 * \author
130 * inspired by Mark Andrews.
131 * \author
132 * Paul Vixie, 1996.
133 */
134 static int
inet_pton6(const char * src,unsigned char * dst)135 inet_pton6(const char *src, unsigned char *dst) {
136 static const char xdigits_l[] = "0123456789abcdef",
137 xdigits_u[] = "0123456789ABCDEF";
138 unsigned char tmp[NS_IN6ADDRSZ], *tp, *endp, *colonp;
139 const char *xdigits, *curtok;
140 int ch, seen_xdigits;
141 unsigned int val;
142
143 memset((tp = tmp), '\0', NS_IN6ADDRSZ);
144 endp = tp + NS_IN6ADDRSZ;
145 colonp = NULL;
146 /* Leading :: requires some special handling. */
147 if (*src == ':')
148 if (*++src != ':')
149 return (0);
150 curtok = src;
151 seen_xdigits = 0;
152 val = 0;
153 while ((ch = *src++) != '\0') {
154 const char *pch;
155
156 if ((pch = strchr((xdigits = xdigits_l), ch)) == NULL)
157 pch = strchr((xdigits = xdigits_u), ch);
158 if (pch != NULL) {
159 val <<= 4;
160 val |= (pch - xdigits);
161 if (++seen_xdigits > 4)
162 return (0);
163 continue;
164 }
165 if (ch == ':') {
166 curtok = src;
167 if (!seen_xdigits) {
168 if (colonp)
169 return (0);
170 colonp = tp;
171 continue;
172 }
173 if (NS_INT16SZ > endp - tp)
174 return (0);
175 *tp++ = (unsigned char) (val >> 8) & 0xff;
176 *tp++ = (unsigned char) val & 0xff;
177 seen_xdigits = 0;
178 val = 0;
179 continue;
180 }
181 if (ch == '.' && (NS_INADDRSZ <= endp - tp) &&
182 inet_pton4(curtok, tp) > 0) {
183 tp += NS_INADDRSZ;
184 seen_xdigits = 0;
185 break; /* '\0' was seen by inet_pton4(). */
186 }
187 return (0);
188 }
189 if (seen_xdigits) {
190 if (NS_INT16SZ > endp - tp)
191 return (0);
192 *tp++ = (unsigned char) (val >> 8) & 0xff;
193 *tp++ = (unsigned char) val & 0xff;
194 }
195 if (colonp != NULL) {
196 /*
197 * Since some memmove()'s erroneously fail to handle
198 * overlapping regions, we'll do the shift by hand.
199 */
200 const size_t n = tp - colonp;
201 int i;
202
203 if (tp == endp)
204 return (0);
205 for (i = 1; (size_t)i <= n; i++) {
206 endp[- i] = colonp[n - i];
207 colonp[n - i] = 0;
208 }
209 tp = endp;
210 }
211 if (tp != endp)
212 return (0);
213 memcpy(dst, tmp, NS_IN6ADDRSZ);
214 return (1);
215 }
216