xref: /freebsd/crypto/openssh/openbsd-compat/inet_aton.c (revision 6b3455a7665208c366849f0b2b3bc916fb97516e)
1 /* OPENBSD ORIGINAL: lib/libc/net/inet_addr.c */
2 
3 /*	$OpenBSD: inet_addr.c,v 1.7 2003/06/02 20:18:35 millert Exp $	*/
4 
5 /*
6  * Copyright (c) 1983, 1990, 1993
7  *    The Regents of the University of California.  All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  * -
33  * Portions Copyright (c) 1993 by Digital Equipment Corporation.
34  *
35  * Permission to use, copy, modify, and distribute this software for any
36  * purpose with or without fee is hereby granted, provided that the above
37  * copyright notice and this permission notice appear in all copies, and that
38  * the name of Digital Equipment Corporation not be used in advertising or
39  * publicity pertaining to distribution of the document or software without
40  * specific, written prior permission.
41  *
42  * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
43  * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
44  * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
45  * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
46  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
47  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
48  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
49  * SOFTWARE.
50  * -
51  * --Copyright--
52  */
53 
54 #include "includes.h"
55 
56 #if !defined(HAVE_INET_ATON)
57 
58 #if defined(LIBC_SCCS) && !defined(lint)
59 #if 0
60 static char sccsid[] = "@(#)inet_addr.c	8.1 (Berkeley) 6/17/93";
61 static char rcsid[] = "$From: inet_addr.c,v 8.5 1996/08/05 08:31:35 vixie Exp $";
62 #else
63 static char rcsid[] = "$OpenBSD: inet_addr.c,v 1.7 2003/06/02 20:18:35 millert Exp $";
64 #endif
65 #endif /* LIBC_SCCS and not lint */
66 
67 #include <sys/types.h>
68 #include <sys/param.h>
69 #include <netinet/in.h>
70 #include <arpa/inet.h>
71 #include <ctype.h>
72 
73 #if 0
74 /*
75  * Ascii internet address interpretation routine.
76  * The value returned is in network order.
77  */
78 in_addr_t
79 inet_addr(cp)
80 	register const char *cp;
81 {
82 	struct in_addr val;
83 
84 	if (inet_aton(cp, &val))
85 		return (val.s_addr);
86 	return (INADDR_NONE);
87 }
88 #endif
89 
90 /*
91  * Check whether "cp" is a valid ascii representation
92  * of an Internet address and convert to a binary address.
93  * Returns 1 if the address is valid, 0 if not.
94  * This replaces inet_addr, the return value from which
95  * cannot distinguish between failure and a local broadcast address.
96  */
97 int
98 inet_aton(const char *cp, struct in_addr *addr)
99 {
100 	register u_int32_t val;
101 	register int base, n;
102 	register char c;
103 	unsigned int parts[4];
104 	register unsigned int *pp = parts;
105 
106 	c = *cp;
107 	for (;;) {
108 		/*
109 		 * Collect number up to ``.''.
110 		 * Values are specified as for C:
111 		 * 0x=hex, 0=octal, isdigit=decimal.
112 		 */
113 		if (!isdigit(c))
114 			return (0);
115 		val = 0; base = 10;
116 		if (c == '0') {
117 			c = *++cp;
118 			if (c == 'x' || c == 'X')
119 				base = 16, c = *++cp;
120 			else
121 				base = 8;
122 		}
123 		for (;;) {
124 			if (isascii(c) && isdigit(c)) {
125 				val = (val * base) + (c - '0');
126 				c = *++cp;
127 			} else if (base == 16 && isascii(c) && isxdigit(c)) {
128 				val = (val << 4) |
129 					(c + 10 - (islower(c) ? 'a' : 'A'));
130 				c = *++cp;
131 			} else
132 				break;
133 		}
134 		if (c == '.') {
135 			/*
136 			 * Internet format:
137 			 *	a.b.c.d
138 			 *	a.b.c	(with c treated as 16 bits)
139 			 *	a.b	(with b treated as 24 bits)
140 			 */
141 			if (pp >= parts + 3)
142 				return (0);
143 			*pp++ = val;
144 			c = *++cp;
145 		} else
146 			break;
147 	}
148 	/*
149 	 * Check for trailing characters.
150 	 */
151 	if (c != '\0' && (!isascii(c) || !isspace(c)))
152 		return (0);
153 	/*
154 	 * Concoct the address according to
155 	 * the number of parts specified.
156 	 */
157 	n = pp - parts + 1;
158 	switch (n) {
159 
160 	case 0:
161 		return (0);		/* initial nondigit */
162 
163 	case 1:				/* a -- 32 bits */
164 		break;
165 
166 	case 2:				/* a.b -- 8.24 bits */
167 		if ((val > 0xffffff) || (parts[0] > 0xff))
168 			return (0);
169 		val |= parts[0] << 24;
170 		break;
171 
172 	case 3:				/* a.b.c -- 8.8.16 bits */
173 		if ((val > 0xffff) || (parts[0] > 0xff) || (parts[1] > 0xff))
174 			return (0);
175 		val |= (parts[0] << 24) | (parts[1] << 16);
176 		break;
177 
178 	case 4:				/* a.b.c.d -- 8.8.8.8 bits */
179 		if ((val > 0xff) || (parts[0] > 0xff) || (parts[1] > 0xff) || (parts[2] > 0xff))
180 			return (0);
181 		val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
182 		break;
183 	}
184 	if (addr)
185 		addr->s_addr = htonl(val);
186 	return (1);
187 }
188 
189 #endif /* !defined(HAVE_INET_ATON) */
190