xref: /minix/external/bsd/bind/dist/lib/lwres/lwinetpton.c (revision bb9622b5)
1 /*	$NetBSD: lwinetpton.c,v 1.6 2014/12/10 04:38:02 christos Exp $	*/
2 
3 /*
4  * Copyright (C) 2004, 2005, 2007, 2011-2014  Internet Systems Consortium, Inc. ("ISC")
5  * Copyright (C) 1996-2001  Internet Software Consortium.
6  *
7  * Permission to use, copy, modify, and/or distribute this software for any
8  * purpose with or without fee is hereby granted, provided that the above
9  * copyright notice and this permission notice appear in all copies.
10  *
11  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
12  * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
13  * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
14  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
15  * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
16  * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
17  * PERFORMANCE OF THIS SOFTWARE.
18  */
19 
20 /*! \file lwinetpton.c
21  */
22 
23 #if defined(LIBC_SCCS) && !defined(lint)
24 static char rcsid[] = "Id";
25 #endif /* LIBC_SCCS and not lint */
26 
27 #include <config.h>
28 
29 #include <errno.h>
30 #include <string.h>
31 
32 #include <lwres/net.h>
33 
34 #define NS_INT16SZ	 2
35 #define NS_INADDRSZ	 4
36 #define NS_IN6ADDRSZ	16
37 
38 /*
39  * WARNING: Don't even consider trying to compile this on a system where
40  * sizeof(int) < 4.  sizeof(int) > 4 is fine; all the world's not a VAX.
41  */
42 
43 static int inet_pton4(const char *src, unsigned char *dst);
44 static int inet_pton6(const char *src, unsigned char *dst);
45 
46 /*!
47  * int
48  * lwres_net_pton(af, src, dst)
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
59 lwres_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 /*! int
73  * inet_pton4(src, dst)
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  * notice:
78  *	does not touch `dst' unless it's returning 1.
79  * author:
80  *	Paul Vixie, 1996.
81  */
82 static int
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 			unsigned int new = *tp * 10;
96 
97 			new += (unsigned int)(pch - digits);
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 			/*
110 			 * "clang --analyse" generates warnings using:
111 			 * 		*++tp = 0;
112 			 */
113 			tp++;
114 			*tp = 0;
115 			saw_digit = 0;
116 		} else
117 			return (0);
118 	}
119 	if (octets < 4)
120 		return (0);
121 	memmove(dst, tmp, NS_INADDRSZ);
122 	return (1);
123 }
124 
125 /*! int
126  * inet_pton6(src, dst)
127  *	convert presentation level address to network order binary form.
128  * return:
129  *	1 if `src' is a valid [RFC1884 2.2] address, else 0.
130  * notice:
131  *	(1) does not touch `dst' unless it's returning 1.
132  *	(2) :: in a full address is silently ignored.
133  * credit:
134  *	inspired by Mark Andrews.
135  * author:
136  *	Paul Vixie, 1996.
137  */
138 static int
139 inet_pton6(const char *src, unsigned char *dst) {
140 	static const char xdigits_l[] = "0123456789abcdef",
141 			  xdigits_u[] = "0123456789ABCDEF";
142 	unsigned char tmp[NS_IN6ADDRSZ], *tp, *endp, *colonp;
143 	const char *xdigits, *curtok;
144 	int ch, seen_xdigits;
145 	unsigned int val;
146 
147 	memset((tp = tmp), '\0', NS_IN6ADDRSZ);
148 	endp = tp + NS_IN6ADDRSZ;
149 	colonp = NULL;
150 	/* Leading :: requires some special handling. */
151 	if (*src == ':')
152 		if (*++src != ':')
153 			return (0);
154 	curtok = src;
155 	seen_xdigits = 0;
156 	val = 0;
157 	while ((ch = *src++) != '\0') {
158 		const char *pch;
159 
160 		if ((pch = strchr((xdigits = xdigits_l), ch)) == NULL)
161 			pch = strchr((xdigits = xdigits_u), ch);
162 		if (pch != NULL) {
163 			val <<= 4;
164 			val |= (pch - xdigits);
165 			if (++seen_xdigits > 4)
166 				return (0);
167 			continue;
168 		}
169 		if (ch == ':') {
170 			curtok = src;
171 			if (!seen_xdigits) {
172 				if (colonp)
173 					return (0);
174 				colonp = tp;
175 				continue;
176 			}
177 			if (tp + NS_INT16SZ > endp)
178 				return (0);
179 			*tp++ = (unsigned char) (val >> 8) & 0xff;
180 			*tp++ = (unsigned char) val & 0xff;
181 			seen_xdigits = 0;
182 			val = 0;
183 			continue;
184 		}
185 		if (ch == '.' && ((tp + NS_INADDRSZ) <= endp) &&
186 		    inet_pton4(curtok, tp) > 0) {
187 			tp += NS_INADDRSZ;
188 			seen_xdigits = 0;
189 			break;	/* '\0' was seen by inet_pton4(). */
190 		}
191 		return (0);
192 	}
193 	if (seen_xdigits) {
194 		if (tp + NS_INT16SZ > endp)
195 			return (0);
196 		*tp++ = (unsigned char) (val >> 8) & 0xff;
197 		*tp++ = (unsigned char) val & 0xff;
198 	}
199 	if (colonp != NULL) {
200 		/*
201 		 * Since some memmove()'s erroneously fail to handle
202 		 * overlapping regions, we'll do the shift by hand.
203 		 */
204 		const int n = (int)(tp - colonp);
205 		int i;
206 
207 		for (i = 1; i <= n; i++) {
208 			endp[- i] = colonp[n - i];
209 			colonp[n - i] = 0;
210 		}
211 		tp = endp;
212 	}
213 	if (tp != endp)
214 		return (0);
215 	memmove(dst, tmp, NS_IN6ADDRSZ);
216 	return (1);
217 }
218