xref: /titanic_52/usr/src/lib/libnsl/nss/inet_pton.c (revision 911106dfb16696472af8c1b7b4c554a829354fa8)
1 /*
2  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
3  * Use is subject to license terms.
4  */
5 
6 /*
7  * Copyright (c) 1996 by Internet Software Consortium.
8  *
9  * Permission to use, copy, modify, and distribute this software for any
10  * purpose with or without fee is hereby granted, provided that the above
11  * copyright notice and this permission notice appear in all copies.
12  *
13  * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
14  * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
15  * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
16  * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
17  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
18  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
19  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
20  * SOFTWARE.
21  */
22 
23 #pragma ident	"%Z%%M%	%I%	%E% SMI"
24 
25 #include "mt.h"
26 #include <stdlib.h>
27 #include <ctype.h>
28 #include <string.h>
29 #include <strings.h>
30 #include <netdb.h>
31 #include <stdio.h>
32 #include <arpa/inet.h>
33 #include <netinet/in.h>
34 #include <sys/socket.h>
35 #include <errno.h>
36 
37 static int	inet_pton4(const char *src, uchar_t *dst);
38 static int	inet_pton6(const char *src, uchar_t *dst);
39 
40 /*
41  * int
42  * inet_pton(af, src, dst)
43  *	convert from presentation format (which usually means ASCII printable)
44  *	to network format (which is usually some kind of binary format).
45  * return:
46  *	1 if the address was valid for the specified address family
47  *	0 if the address wasn't valid (`dst' is untouched in this case)
48  *	-1 if some other error occurred (`dst' is untouched in this case, too)
49  * author:
50  *	Paul Vixie, 1996.  Taken from on297-gate:dns stuff
51  */
52 int
53 inet_pton(int af, const char *src, void *dst)
54 {
55 	switch (af) {
56 	case AF_INET:
57 		return (inet_pton4(src, dst));
58 	case AF_INET6:
59 		return (inet_pton6(src, dst));
60 	default:
61 		errno = EAFNOSUPPORT;
62 		return (-1);
63 	}
64 	/* NOTREACHED */
65 }
66 
67 /*
68  * int
69  * inet_pton4(src, dst)
70  *	like inet_aton() but without all the hexadecimal and shorthand.
71  * return:
72  *	1 if `src' is a valid dotted quad, else 0.
73  * notice:
74  *	does not touch `dst' unless it's returning 1.
75  *
76  */
77 #define	INADDRSZ	4
78 #define	IN6ADDRSZ	16
79 #define	INT16SZ		2
80 
81 static int
82 inet_pton4(const char *src, uchar_t *dst)
83 {
84 	static const char digits[] = "0123456789";
85 	int saw_digit, octets, ch;
86 	uchar_t tmp[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 			uint_t new = *tp * 10 + (pch - digits);
96 
97 			if (new > 255)
98 				return (0);
99 			*tp = new;
100 			if (!saw_digit) {
101 				if (++octets > 4)
102 					return (0);
103 				saw_digit = 1;
104 			}
105 		} else if (ch == '.' && saw_digit) {
106 			if (octets == 4)
107 				return (0);
108 			*++tp = 0;
109 			saw_digit = 0;
110 		} else
111 			return (0);
112 	}
113 	if (octets < 4)
114 		return (0);
115 
116 	(void) memcpy(dst, tmp, INADDRSZ);
117 	return (1);
118 }
119 
120 
121 /*
122  * int
123  * inet_pton6(src, dst)
124  *	convert presentation level address to network order binary form.
125  * return:
126  *	1 if `src' is a valid [RFC1884 2.2] address, else 0.
127  * notice:
128  *	(1) does not touch `dst' unless it's returning 1.
129  *	(2) :: in a full address is silently ignored.
130  * credit:
131  *	inspired by Mark Andrews.
132  *
133  */
134 
135 
136 static int
137 inet_pton6(const char *src, uchar_t *dst)
138 {
139 	static const char xdigits_l[] = "0123456789abcdef",
140 			xdigits_u[] = "0123456789ABCDEF";
141 	uchar_t tmp[IN6ADDRSZ], *tp, *endp, *colonp;
142 	const char *xdigits, *curtok;
143 	int ch, saw_xdigit;
144 	uint_t val;
145 
146 	(void) memset((tp = tmp), '\0', IN6ADDRSZ);
147 	endp = tp + IN6ADDRSZ;
148 	colonp = NULL;
149 	/* Leading :: requires some special handling. */
150 	if (*src == ':')
151 		if (*++src != ':')
152 			return (0);
153 	curtok = src;
154 	saw_xdigit = 0;
155 	val = 0;
156 	while ((ch = *src++) != '\0') {
157 		const char *pch;
158 
159 		if ((pch = strchr((xdigits = xdigits_l), ch)) == NULL)
160 			pch = strchr((xdigits = xdigits_u), ch);
161 		if (pch != NULL) {
162 			val <<= 4;
163 			val |= (pch - xdigits);
164 			if (val > 0xffff)
165 				return (0);
166 			saw_xdigit = 1;
167 			continue;
168 		}
169 		if (ch == ':') {
170 			curtok = src;
171 			if (!saw_xdigit) {
172 				if (colonp)
173 					return (0);
174 				colonp = tp;
175 				continue;
176 			} else if (*src == '\0') {
177 				return (0);
178 			}
179 			if (tp + INT16SZ > endp)
180 				return (0);
181 			*tp++ = (uchar_t)(val >> 8) & 0xff;
182 			*tp++ = (uchar_t)val & 0xff;
183 			saw_xdigit = 0;
184 			val = 0;
185 			continue;
186 		}
187 		if (ch == '.' && ((tp + INADDRSZ) <= endp) &&
188 		    inet_pton4(curtok, tp) > 0) {
189 			tp += INADDRSZ;
190 			saw_xdigit = 0;
191 			break;	/* '\0' was seen by inet_pton4(). */
192 		}
193 		return (0);
194 	}
195 	if (saw_xdigit) {
196 		if (tp + INT16SZ > endp)
197 			return (0);
198 		*tp++ = (uchar_t)(val >> 8) & 0xff;
199 		*tp++ = (uchar_t)val & 0xff;
200 	}
201 	if (colonp != NULL) {
202 		/*
203 		 * Since some memmove()'s erroneously fail to handle
204 		 * overlapping regions, we'll do the shift by hand.
205 		 */
206 		const int n = tp - colonp;
207 		int i;
208 
209 		if (tp == endp)
210 			return (0);
211 		for (i = 1; i <= n; i++) {
212 			endp[- i] = colonp[n - i];
213 			colonp[n - i] = 0;
214 		}
215 		tp = endp;
216 	}
217 	if (tp != endp)
218 		return (0);
219 	(void) memcpy(dst, tmp, IN6ADDRSZ);
220 	return (1);
221 }
222