xref: /freebsd/contrib/ldns/compat/inet_pton.c (revision b0d29bc47dba79f6f38e67eabadfb4b32ffd9390)
1 /*	$KAME: inet_pton.c,v 1.5 2001/08/20 02:32:40 itojun Exp $	*/
2 
3 /* Copyright (c) 1996 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 INTERNET SOFTWARE CONSORTIUM DISCLAIMS
10  * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
11  * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
12  * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
13  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
14  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
15  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
16  * SOFTWARE.
17  */
18 
19 #include <ldns/config.h>
20 
21 #include <string.h>
22 #include <stdio.h>
23 #include <errno.h>
24 
25 /*
26  * WARNING: Don't even consider trying to compile this on a system where
27  * sizeof(int) < 4.  sizeof(int) > 4 is fine; all the world's not a VAX.
28  */
29 
30 static int	inet_pton4 (const char *src, uint8_t *dst);
31 static int	inet_pton6 (const char *src, uint8_t *dst);
32 
33 /*
34  *
35  * The definitions we might miss.
36  *
37  */
38 #ifndef NS_INT16SZ
39 #define	NS_INT16SZ	2
40 #endif
41 
42 #ifndef NS_IN6ADDRSZ
43 #define NS_IN6ADDRSZ 16
44 #endif
45 
46 #ifndef NS_INADDRSZ
47 #define NS_INADDRSZ 4
48 #endif
49 
50 /* int
51  * inet_pton(af, src, dst)
52  *	convert from presentation format (which usually means ASCII printable)
53  *	to network format (which is usually some kind of binary format).
54  * return:
55  *	1 if the address was valid for the specified address family
56  *	0 if the address wasn't valid (`dst' is untouched in this case)
57  *	-1 if some other error occurred (`dst' is untouched in this case, too)
58  * author:
59  *	Paul Vixie, 1996.
60  */
61 int
62 inet_pton(af, src, dst)
63 	int af;
64 	const char *src;
65 	void *dst;
66 {
67 	switch (af) {
68 	case AF_INET:
69 		return (inet_pton4(src, dst));
70 	case AF_INET6:
71 		return (inet_pton6(src, dst));
72 	default:
73 #ifdef EAFNOSUPPORT
74 		errno = EAFNOSUPPORT;
75 #else
76 		errno = ENOSYS;
77 #endif
78 		return (-1);
79 	}
80 	/* NOTREACHED */
81 }
82 
83 /* int
84  * inet_pton4(src, dst)
85  *	like inet_aton() but without all the hexadecimal and shorthand.
86  * return:
87  *	1 if `src' is a valid dotted quad, else 0.
88  * notice:
89  *	does not touch `dst' unless it's returning 1.
90  * author:
91  *	Paul Vixie, 1996.
92  */
93 static int
94 inet_pton4(src, dst)
95 	const char *src;
96 	uint8_t *dst;
97 {
98 	static const char digits[] = "0123456789";
99 	int saw_digit, octets, ch;
100 	uint8_t tmp[NS_INADDRSZ], *tp;
101 
102 	saw_digit = 0;
103 	octets = 0;
104 	*(tp = tmp) = 0;
105 	while ((ch = *src++) != '\0') {
106 		const char *pch;
107 
108 		if ((pch = strchr(digits, ch)) != NULL) {
109 			uint32_t new = *tp * 10 + (pch - digits);
110 
111 			if (new > 255)
112 				return (0);
113 			*tp = new;
114 			if (! saw_digit) {
115 				if (++octets > 4)
116 					return (0);
117 				saw_digit = 1;
118 			}
119 		} else if (ch == '.' && saw_digit) {
120 			if (octets == 4)
121 				return (0);
122 			*++tp = 0;
123 			saw_digit = 0;
124 		} else
125 			return (0);
126 	}
127 	if (octets < 4)
128 		return (0);
129 
130 	memcpy(dst, tmp, NS_INADDRSZ);
131 	return (1);
132 }
133 
134 /* int
135  * inet_pton6(src, dst)
136  *	convert presentation level address to network order binary form.
137  * return:
138  *	1 if `src' is a valid [RFC1884 2.2] address, else 0.
139  * notice:
140  *	(1) does not touch `dst' unless it's returning 1.
141  *	(2) :: in a full address is silently ignored.
142  * credit:
143  *	inspired by Mark Andrews.
144  * author:
145  *	Paul Vixie, 1996.
146  */
147 static int
148 inet_pton6(src, dst)
149 	const char *src;
150 	uint8_t *dst;
151 {
152 	static const char xdigits_l[] = "0123456789abcdef",
153 			  xdigits_u[] = "0123456789ABCDEF";
154 	uint8_t tmp[NS_IN6ADDRSZ], *tp, *endp, *colonp;
155 	const char *xdigits, *curtok;
156 	int ch, saw_xdigit;
157 	uint32_t val;
158 
159 	memset((tp = tmp), '\0', NS_IN6ADDRSZ);
160 	endp = tp + NS_IN6ADDRSZ;
161 	colonp = NULL;
162 	/* Leading :: requires some special handling. */
163 	if (*src == ':')
164 		if (*++src != ':')
165 			return (0);
166 	curtok = src;
167 	saw_xdigit = 0;
168 	val = 0;
169 	while ((ch = *src++) != '\0') {
170 		const char *pch;
171 
172 		if ((pch = strchr((xdigits = xdigits_l), ch)) == NULL)
173 			pch = strchr((xdigits = xdigits_u), ch);
174 		if (pch != NULL) {
175 			val <<= 4;
176 			val |= (pch - xdigits);
177 			if (val > 0xffff)
178 				return (0);
179 			saw_xdigit = 1;
180 			continue;
181 		}
182 		if (ch == ':') {
183 			curtok = src;
184 			if (!saw_xdigit) {
185 				if (colonp)
186 					return (0);
187 				colonp = tp;
188 				continue;
189 			}
190 			if (tp + NS_INT16SZ > endp)
191 				return (0);
192 			*tp++ = (uint8_t) (val >> 8) & 0xff;
193 			*tp++ = (uint8_t) val & 0xff;
194 			saw_xdigit = 0;
195 			val = 0;
196 			continue;
197 		}
198 		if (ch == '.' && ((tp + NS_INADDRSZ) <= endp) &&
199 		    inet_pton4(curtok, tp) > 0) {
200 			tp += NS_INADDRSZ;
201 			saw_xdigit = 0;
202 			break;	/* '\0' was seen by inet_pton4(). */
203 		}
204 		return (0);
205 	}
206 	if (saw_xdigit) {
207 		if (tp + NS_INT16SZ > endp)
208 			return (0);
209 		*tp++ = (uint8_t) (val >> 8) & 0xff;
210 		*tp++ = (uint8_t) val & 0xff;
211 	}
212 	if (colonp != NULL) {
213 		/*
214 		 * Since some memmove()'s erroneously fail to handle
215 		 * overlapping regions, we'll do the shift by hand.
216 		 */
217 		const int n = tp - colonp;
218 		int i;
219 
220 		for (i = 1; i <= n; i++) {
221 			endp[- i] = colonp[n - i];
222 			colonp[n - i] = 0;
223 		}
224 		tp = endp;
225 	}
226 	if (tp != endp)
227 		return (0);
228 	memcpy(dst, tmp, NS_IN6ADDRSZ);
229 	return (1);
230 }
231