xref: /illumos-gate/usr/src/lib/libc/port/inet/inet_pton.c (revision 7c478bd9)
1 /*
2  * Copyright (c) 1998, by Sun Microsystems, Inc.
3  * All rights reserved.
4  */
5 
6 /* Copyright (c) 1996 by Internet Software Consortium.
7  *
8  * Permission to use, copy, modify, and distribute this software for any
9  * purpose with or without fee is hereby granted, provided that the above
10  * copyright notice and this permission notice appear in all copies.
11  *
12  * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
13  * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
14  * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
15  * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
16  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
17  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
18  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
19  * SOFTWARE.
20  */
21 #pragma ident	"%Z%%M%	%I%	%E% SMI"
22 
23 #include <stdlib.h>
24 #include <ctype.h>
25 #include <string.h>
26 #include <strings.h>
27 #include <netdb.h>
28 #include <stdio.h>
29 #include <arpa/inet.h>
30 #include <netinet/in.h>
31 #include <sys/socket.h>
32 #include <errno.h>
33 
34 static int	inet_pton4 (const char *src, u_char *dst);
35 static int	inet_pton6 (const char *src, u_char *dst);
36 
37 /* int
38  * inet_pton(af, src, dst)
39  *	convert from presentation format (which usually means ASCII printable)
40  *	to network format (which is usually some kind of binary format).
41  * return:
42  *	1 if the address was valid for the specified address family
43  *	0 if the address wasn't valid (`dst' is untouched in this case)
44  *	-1 if some other error occurred (`dst' is untouched in this case, too)
45  * author:
46  *	Paul Vixie, 1996.  Taken from on297-gate:dns stuff
47  */
48 int
49 inet_pton(af, src, dst)
50 	int af;
51 	const char *src;
52 	void *dst;
53 {
54 	switch (af) {
55 	case AF_INET:
56 		return (inet_pton4(src, dst));
57 	case AF_INET6:
58 		return (inet_pton6(src, dst));
59 	default:
60 		errno = EAFNOSUPPORT;
61 		return (-1);
62 	}
63 	/* NOTREACHED */
64 }
65 
66 /* int
67  * inet_pton4(src, dst)
68  *	like inet_aton() but without all the hexadecimal and shorthand.
69  * return:
70  *	1 if `src' is a valid dotted quad, else 0.
71  * notice:
72  *	does not touch `dst' unless it's returning 1.
73  *
74  */
75 #define INADDRSZ	4
76 #define	IN6ADDRSZ	16
77 #define INT16SZ		2
78 static int
79 inet_pton4(src, dst)
80 	const char *src;
81 	u_char *dst;
82 {
83 	static const char digits[] = "0123456789";
84 	int saw_digit, octets, ch;
85 	u_char tmp[INADDRSZ], *tp;
86 
87 	saw_digit = 0;
88 	octets = 0;
89 	*(tp = tmp) = 0;
90 	while ((ch = *src++) != '\0') {
91 		const char *pch;
92 
93 		if ((pch = strchr(digits, ch)) != NULL) {
94 			u_int new = *tp * 10 + (pch - digits);
95 
96 			if (new > 255)
97 				return (0);
98 			*tp = new;
99 			if (! saw_digit) {
100 				if (++octets > 4)
101 					return (0);
102 				saw_digit = 1;
103 			}
104 		} else if (ch == '.' && saw_digit) {
105 			if (octets == 4)
106 				return (0);
107 			*++tp = 0;
108 			saw_digit = 0;
109 		} else
110 			return (0);
111 	}
112 	if (octets < 4)
113 		return (0);
114 
115 	memcpy(dst, tmp, INADDRSZ);
116 	return (1);
117 }
118 
119 
120 /* int
121  * inet_pton6(src, dst)
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  * notice:
126  *	(1) does not touch `dst' unless it's returning 1.
127  *	(2) :: in a full address is silently ignored.
128  * credit:
129  *	inspired by Mark Andrews.
130  *
131  */
132 
133 
134 static int
135 inet_pton6(src, dst)
136 	const char *src;
137 	u_char *dst;
138 {
139 	static const char xdigits_l[] = "0123456789abcdef",
140 			  xdigits_u[] = "0123456789ABCDEF";
141 	u_char tmp[IN6ADDRSZ], *tp, *endp, *colonp;
142 	const char *xdigits, *curtok;
143 	int ch, saw_xdigit;
144 	u_int val;
145 
146 	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++ = (u_char) (val >> 8) & 0xff;
182 			*tp++ = (u_char) 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++ = (u_char) (val >> 8) & 0xff;
199 		*tp++ = (u_char) 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 	memcpy(dst, tmp, IN6ADDRSZ);
220 	return (1);
221 }
222