xref: /freebsd/contrib/unbound/compat/inet_aton.c (revision 40a8ac8f62b535d30349faf28cf47106b7041b83)
1 /* From openssh4.3p2 compat/inet_aton.c */
2 /*
3  * Copyright (c) 1983, 1990, 1993
4  *    The Regents of the University of California.  All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. Neither the name of the University nor the names of its contributors
15  *    may be used to endorse or promote products derived from this software
16  *    without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  * -
30  * Portions Copyright (c) 1993 by Digital Equipment Corporation.
31  *
32  * Permission to use, copy, modify, and distribute this software for any
33  * purpose with or without fee is hereby granted, provided that the above
34  * copyright notice and this permission notice appear in all copies, and that
35  * the name of Digital Equipment Corporation not be used in advertising or
36  * publicity pertaining to distribution of the document or software without
37  * specific, written prior permission.
38  *
39  * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
40  * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
41  * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
42  * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
43  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
44  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
45  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
46  * SOFTWARE.
47  * -
48  * --Copyright--
49  */
50 
51 /* OPENBSD ORIGINAL: lib/libc/net/inet_addr.c */
52 
53 #include <config.h>
54 
55 #if !defined(HAVE_INET_ATON)
56 
57 #include <sys/types.h>
58 #include <sys/param.h>
59 #ifdef HAVE_NETINET_IN_H
60 #include <netinet/in.h>
61 #endif
62 #ifdef HAVE_ARPA_INET_H
63 #include <arpa/inet.h>
64 #endif
65 #include <ctype.h>
66 
67 #if 0
68 /*
69  * Ascii internet address interpretation routine.
70  * The value returned is in network order.
71  */
72 in_addr_t
73 inet_addr(const char *cp)
74 {
75 	struct in_addr val;
76 
77 	if (inet_aton(cp, &val))
78 		return (val.s_addr);
79 	return (INADDR_NONE);
80 }
81 #endif
82 
83 /*
84  * Check whether "cp" is a valid ascii representation
85  * of an Internet address and convert to a binary address.
86  * Returns 1 if the address is valid, 0 if not.
87  * This replaces inet_addr, the return value from which
88  * cannot distinguish between failure and a local broadcast address.
89  */
90 int
91 inet_aton(const char *cp, struct in_addr *addr)
92 {
93 	uint32_t val;
94 	int base, n;
95 	char c;
96 	unsigned int parts[4];
97 	unsigned int *pp = parts;
98 
99 	c = *cp;
100 	for (;;) {
101 		/*
102 		 * Collect number up to ``.''.
103 		 * Values are specified as for C:
104 		 * 0x=hex, 0=octal, isdigit=decimal.
105 		 */
106 		if (!isdigit(c))
107 			return (0);
108 		val = 0; base = 10;
109 		if (c == '0') {
110 			c = *++cp;
111 			if (c == 'x' || c == 'X')
112 				base = 16, c = *++cp;
113 			else
114 				base = 8;
115 		}
116 		for (;;) {
117 			if (isascii(c) && isdigit(c)) {
118 				val = (val * base) + (c - '0');
119 				c = *++cp;
120 			} else if (base == 16 && isascii(c) && isxdigit(c)) {
121 				val = (val << 4) |
122 					(c + 10 - (islower(c) ? 'a' : 'A'));
123 				c = *++cp;
124 			} else
125 				break;
126 		}
127 		if (c == '.') {
128 			/*
129 			 * Internet format:
130 			 *	a.b.c.d
131 			 *	a.b.c	(with c treated as 16 bits)
132 			 *	a.b	(with b treated as 24 bits)
133 			 */
134 			if (pp >= parts + 3)
135 				return (0);
136 			*pp++ = val;
137 			c = *++cp;
138 		} else
139 			break;
140 	}
141 	/*
142 	 * Check for trailing characters.
143 	 */
144 	if (c != '\0' && (!isascii(c) || !isspace(c)))
145 		return (0);
146 	/*
147 	 * Concoct the address according to
148 	 * the number of parts specified.
149 	 */
150 	n = pp - parts + 1;
151 	switch (n) {
152 
153 	case 0:
154 		return (0);		/* initial nondigit */
155 
156 	case 1:				/* a -- 32 bits */
157 		break;
158 
159 	case 2:				/* a.b -- 8.24 bits */
160 		if ((val > 0xffffff) || (parts[0] > 0xff))
161 			return (0);
162 		val |= parts[0] << 24;
163 		break;
164 
165 	case 3:				/* a.b.c -- 8.8.16 bits */
166 		if ((val > 0xffff) || (parts[0] > 0xff) || (parts[1] > 0xff))
167 			return (0);
168 		val |= (parts[0] << 24) | (parts[1] << 16);
169 		break;
170 
171 	case 4:				/* a.b.c.d -- 8.8.8.8 bits */
172 		if ((val > 0xff) || (parts[0] > 0xff) || (parts[1] > 0xff) || (parts[2] > 0xff))
173 			return (0);
174 		val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
175 		break;
176 	}
177 	if (addr)
178 		addr->s_addr = htonl(val);
179 	return (1);
180 }
181 
182 #endif /* !defined(HAVE_INET_ATON) */
183