1 /*	$OpenBSD: inet_addr.c,v 1.9 2005/08/06 20:30:03 espie Exp $	*/
2 
3 /*
4  * Copyright (c) 1983, 1990, 1993
5  *    The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  * -
31  * Portions Copyright (c) 1993 by Digital Equipment Corporation.
32  *
33  * Permission to use, copy, modify, and distribute this software for any
34  * purpose with or without fee is hereby granted, provided that the above
35  * copyright notice and this permission notice appear in all copies, and that
36  * the name of Digital Equipment Corporation not be used in advertising or
37  * publicity pertaining to distribution of the document or software without
38  * specific, written prior permission.
39  *
40  * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
41  * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
42  * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
43  * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
44  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
45  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
46  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
47  * SOFTWARE.
48  * -
49  * --Copyright--
50  */
51 
52 /* OPENBSD ORIGINAL: lib/libc/net/inet_addr.c */
53 
54 #include "includes.h"
55 
56 #if !defined(HAVE_INET_ATON)
57 
58 #include <sys/types.h>
59 #include <sys/param.h>
60 #include <netinet/in.h>
61 #include <arpa/inet.h>
62 #include <ctype.h>
63 
64 #if 0
65 /*
66  * Ascii internet address interpretation routine.
67  * The value returned is in network order.
68  */
69 in_addr_t
70 inet_addr(const char *cp)
71 {
72 	struct in_addr val;
73 
74 	if (inet_aton(cp, &val))
75 		return (val.s_addr);
76 	return (INADDR_NONE);
77 }
78 #endif
79 
80 /*
81  * Check whether "cp" is a valid ascii representation
82  * of an Internet address and convert to a binary address.
83  * Returns 1 if the address is valid, 0 if not.
84  * This replaces inet_addr, the return value from which
85  * cannot distinguish between failure and a local broadcast address.
86  */
87 int
inet_aton(const char * cp,struct in_addr * addr)88 inet_aton(const char *cp, struct in_addr *addr)
89 {
90 	u_int32_t val;
91 	int base, n;
92 	char c;
93 	u_int parts[4];
94 	u_int *pp = parts;
95 
96 	c = *cp;
97 	for (;;) {
98 		/*
99 		 * Collect number up to ``.''.
100 		 * Values are specified as for C:
101 		 * 0x=hex, 0=octal, isdigit=decimal.
102 		 */
103 		if (!isdigit(c))
104 			return (0);
105 		val = 0; base = 10;
106 		if (c == '0') {
107 			c = *++cp;
108 			if (c == 'x' || c == 'X')
109 				base = 16, c = *++cp;
110 			else
111 				base = 8;
112 		}
113 		for (;;) {
114 			if (isascii(c) && isdigit(c)) {
115 				val = (val * base) + (c - '0');
116 				c = *++cp;
117 			} else if (base == 16 && isascii(c) && isxdigit(c)) {
118 				val = (val << 4) |
119 					(c + 10 - (islower(c) ? 'a' : 'A'));
120 				c = *++cp;
121 			} else
122 				break;
123 		}
124 		if (c == '.') {
125 			/*
126 			 * Internet format:
127 			 *	a.b.c.d
128 			 *	a.b.c	(with c treated as 16 bits)
129 			 *	a.b	(with b treated as 24 bits)
130 			 */
131 			if (pp >= parts + 3)
132 				return (0);
133 			*pp++ = val;
134 			c = *++cp;
135 		} else
136 			break;
137 	}
138 	/*
139 	 * Check for trailing characters.
140 	 */
141 	if (c != '\0' && (!isascii(c) || !isspace(c)))
142 		return (0);
143 	/*
144 	 * Concoct the address according to
145 	 * the number of parts specified.
146 	 */
147 	n = pp - parts + 1;
148 	switch (n) {
149 
150 	case 0:
151 		return (0);		/* initial nondigit */
152 
153 	case 1:				/* a -- 32 bits */
154 		break;
155 
156 	case 2:				/* a.b -- 8.24 bits */
157 		if ((val > 0xffffff) || (parts[0] > 0xff))
158 			return (0);
159 		val |= parts[0] << 24;
160 		break;
161 
162 	case 3:				/* a.b.c -- 8.8.16 bits */
163 		if ((val > 0xffff) || (parts[0] > 0xff) || (parts[1] > 0xff))
164 			return (0);
165 		val |= (parts[0] << 24) | (parts[1] << 16);
166 		break;
167 
168 	case 4:				/* a.b.c.d -- 8.8.8.8 bits */
169 		if ((val > 0xff) || (parts[0] > 0xff) || (parts[1] > 0xff) || (parts[2] > 0xff))
170 			return (0);
171 		val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
172 		break;
173 	}
174 	if (addr)
175 		addr->s_addr = htonl(val);
176 	return (1);
177 }
178 
179 #endif /* !defined(HAVE_INET_ATON) */
180