xref: /illumos-gate/usr/src/lib/libc/port/inet/inet_pton.c (revision 22028508fd28d36ff74dc02c5774a8ba1f0db045)
1 /*
2  * Copyright (c) 1996 by Internet Software Consortium.
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
9  * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
10  * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
11  * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
12  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
13  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
14  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
15  * SOFTWARE.
16  */
17 
18 /*
19  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
20  * Use is subject to license terms.
21  */
22 
23 #include "lint.h"
24 
25 #include <sys/socket.h>
26 
27 #include <arpa/inet.h>
28 #include <netinet/in.h>
29 
30 #include <ctype.h>
31 #include <errno.h>
32 #include <netdb.h>
33 #include <stdio.h>
34 #include <stdlib.h>
35 #include <string.h>
36 #include <strings.h>
37 
38 static int	inet_pton4(const char *src, uchar_t *dst);
39 static int	inet_pton6(const char *src, uchar_t *dst);
40 
41 /*
42  * int
43  * inet_pton(af, src, dst)
44  *	convert from presentation format (which usually means ASCII printable)
45  *	to network format (which is usually some kind of binary format).
46  * return:
47  *	1 if the address was valid for the specified address family
48  *	0 if the address wasn't valid (`dst' is untouched in this case)
49  *	-1 if some other error occurred (`dst' is untouched in this case, too)
50  * author:
51  *	Paul Vixie, 1996.  Taken from on297-gate:dns stuff
52  */
53 int
54 inet_pton(int af, const char *src, void *dst)
55 {
56 	switch (af) {
57 	case AF_INET:
58 		return (inet_pton4(src, dst));
59 	case AF_INET6:
60 		return (inet_pton6(src, dst));
61 	default:
62 		errno = EAFNOSUPPORT;
63 		return (-1);
64 	}
65 	/* NOTREACHED */
66 }
67 
68 /*
69  * int
70  * inet_pton4(src, dst)
71  *	like inet_aton() but without all the hexadecimal and shorthand.
72  * return:
73  *	1 if `src' is a valid dotted quad, else 0.
74  * notice:
75  *	does not touch `dst' unless it's returning 1.
76  *
77  */
78 #define	INADDRSZ	4
79 #define	IN6ADDRSZ	16
80 #define	INT16SZ		2
81 
82 static int
83 inet_pton4(const char *src, uchar_t *dst)
84 {
85 	static const char digits[] = "0123456789";
86 	int saw_digit, octets, ch;
87 	uchar_t tmp[INADDRSZ], *tp;
88 
89 	saw_digit = 0;
90 	octets = 0;
91 	*(tp = tmp) = 0;
92 	while ((ch = *src++) != '\0') {
93 		const char *pch;
94 
95 		if ((pch = strchr(digits, ch)) != NULL) {
96 			uint_t new = *tp * 10 + (pch - digits);
97 
98 			if (new > 255)
99 				return (0);
100 			*tp = new;
101 			if (!saw_digit) {
102 				if (++octets > 4)
103 					return (0);
104 				saw_digit = 1;
105 			}
106 		} else if (ch == '.' && saw_digit) {
107 			if (octets == 4)
108 				return (0);
109 			*++tp = 0;
110 			saw_digit = 0;
111 		} else
112 			return (0);
113 	}
114 	if (octets < 4)
115 		return (0);
116 
117 	(void) memcpy(dst, tmp, INADDRSZ);
118 	return (1);
119 }
120 
121 
122 /*
123  * int
124  * inet_pton6(src, dst)
125  *	convert presentation level address to network order binary form.
126  * return:
127  *	1 if `src' is a valid [RFC1884 2.2] address, else 0.
128  * notice:
129  *	(1) does not touch `dst' unless it's returning 1.
130  *	(2) :: in a full address is silently ignored.
131  * credit:
132  *	inspired by Mark Andrews.
133  *
134  */
135 static int
136 inet_pton6(const char *src, uchar_t *dst)
137 {
138 	static const char xdigits_l[] = "0123456789abcdef";
139 	static const char xdigits_u[] = "0123456789ABCDEF";
140 	uchar_t tmp[IN6ADDRSZ], *tp, *endp, *colonp;
141 	const char *xdigits, *curtok;
142 	int ch, saw_xdigit;
143 	uint_t val;
144 
145 	(void) memset((tp = tmp), '\0', IN6ADDRSZ);
146 	endp = tp + IN6ADDRSZ;
147 	colonp = NULL;
148 	/* Leading :: requires some special handling. */
149 	if (*src == ':')
150 		if (*++src != ':')
151 			return (0);
152 	curtok = src;
153 	saw_xdigit = 0;
154 	val = 0;
155 	while ((ch = *src++) != '\0') {
156 		const char *pch;
157 
158 		if ((pch = strchr((xdigits = xdigits_l), ch)) == NULL)
159 			pch = strchr((xdigits = xdigits_u), ch);
160 		if (pch != NULL) {
161 			val <<= 4;
162 			val |= (pch - xdigits);
163 			if (val > 0xffff)
164 				return (0);
165 			saw_xdigit = 1;
166 			continue;
167 		}
168 		if (ch == ':') {
169 			curtok = src;
170 			if (!saw_xdigit) {
171 				if (colonp)
172 					return (0);
173 				colonp = tp;
174 				continue;
175 			} else if (*src == '\0') {
176 				return (0);
177 			}
178 			if (tp + INT16SZ > endp)
179 				return (0);
180 			*tp++ = (uchar_t)(val >> 8) & 0xff;
181 			*tp++ = (uchar_t)val & 0xff;
182 			saw_xdigit = 0;
183 			val = 0;
184 			continue;
185 		}
186 		if (ch == '.' && ((tp + INADDRSZ) <= endp) &&
187 		    inet_pton4(curtok, tp) > 0) {
188 			tp += INADDRSZ;
189 			saw_xdigit = 0;
190 			break;	/* '\0' was seen by inet_pton4(). */
191 		}
192 		return (0);
193 	}
194 	if (saw_xdigit) {
195 		if (tp + INT16SZ > endp)
196 			return (0);
197 		*tp++ = (uchar_t)(val >> 8) & 0xff;
198 		*tp++ = (uchar_t)val & 0xff;
199 	}
200 	if (colonp != NULL) {
201 		/*
202 		 * Since some memmove()'s erroneously fail to handle
203 		 * overlapping regions, we'll do the shift by hand.
204 		 */
205 		const int n = tp - colonp;
206 		int i;
207 
208 		if (tp == endp)
209 			return (0);
210 		for (i = 1; i <= n; i++) {
211 			endp[- i] = colonp[n - i];
212 			colonp[n - i] = 0;
213 		}
214 		tp = endp;
215 	}
216 	if (tp != endp)
217 		return (0);
218 	(void) memcpy(dst, tmp, IN6ADDRSZ);
219 	return (1);
220 }
221