xref: /freebsd/lib/libc/inet/inet_addr.c (revision 273c26a3c3bea87a241d6879abd4f991db180bf0)
1 /*
2  * Copyright (c) 1983, 1990, 1993
3  *    The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 4. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
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 
50 /*
51  * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
52  * Portions Copyright (c) 1996-1999 by Internet Software Consortium.
53  *
54  * Permission to use, copy, modify, and distribute this software for any
55  * purpose with or without fee is hereby granted, provided that the above
56  * copyright notice and this permission notice appear in all copies.
57  *
58  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
59  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
60  * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
61  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
62  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
63  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
64  * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
65  */
66 
67 #if defined(LIBC_SCCS) && !defined(lint)
68 static const char sccsid[] = "@(#)inet_addr.c	8.1 (Berkeley) 6/17/93";
69 static const char rcsid[] = "$Id: inet_addr.c,v 1.5 2005/04/27 04:56:19 sra Exp $";
70 #endif /* LIBC_SCCS and not lint */
71 #include <sys/cdefs.h>
72 __FBSDID("$FreeBSD$");
73 
74 #include "port_before.h"
75 
76 #include <sys/param.h>
77 
78 #include <netinet/in.h>
79 #include <arpa/inet.h>
80 
81 #include <ctype.h>
82 
83 #include "port_after.h"
84 
85 /*%
86  * Ascii internet address interpretation routine.
87  * The value returned is in network order.
88  */
89 in_addr_t		/* XXX should be struct in_addr :( */
90 inet_addr(const char *cp) {
91 	struct in_addr val;
92 
93 	if (inet_aton(cp, &val))
94 		return (val.s_addr);
95 	return (INADDR_NONE);
96 }
97 
98 /*%
99  * Check whether "cp" is a valid ascii representation
100  * of an Internet address and convert to a binary address.
101  * Returns 1 if the address is valid, 0 if not.
102  * This replaces inet_addr, the return value from which
103  * cannot distinguish between failure and a local broadcast address.
104  */
105 int
106 inet_aton(const char *cp, struct in_addr *addr) {
107 	u_long val;
108 	int base, n;
109 	char c;
110 	u_int8_t parts[4];
111 	u_int8_t *pp = parts;
112 	int digit;
113 
114 	c = *cp;
115 	for (;;) {
116 		/*
117 		 * Collect number up to ``.''.
118 		 * Values are specified as for C:
119 		 * 0x=hex, 0=octal, isdigit=decimal.
120 		 */
121 		if (!isdigit((unsigned char)c))
122 			return (0);
123 		val = 0; base = 10; digit = 0;
124 		if (c == '0') {
125 			c = *++cp;
126 			if (c == 'x' || c == 'X')
127 				base = 16, c = *++cp;
128 			else {
129 				base = 8;
130 				digit = 1 ;
131 			}
132 		}
133 		for (;;) {
134 			if (isascii(c) && isdigit((unsigned char)c)) {
135 				if (base == 8 && (c == '8' || c == '9'))
136 					return (0);
137 				val = (val * base) + (c - '0');
138 				c = *++cp;
139 				digit = 1;
140 			} else if (base == 16 && isascii(c) &&
141 				   isxdigit((unsigned char)c)) {
142 				val = (val << 4) |
143 					(c + 10 - (islower((unsigned char)c) ? 'a' : 'A'));
144 				c = *++cp;
145 				digit = 1;
146 			} else
147 				break;
148 		}
149 		if (c == '.') {
150 			/*
151 			 * Internet format:
152 			 *	a.b.c.d
153 			 *	a.b.c	(with c treated as 16 bits)
154 			 *	a.b	(with b treated as 24 bits)
155 			 */
156 			if (pp >= parts + 3 || val > 0xffU)
157 				return (0);
158 			*pp++ = val;
159 			c = *++cp;
160 		} else
161 			break;
162 	}
163 	/*
164 	 * Check for trailing characters.
165 	 */
166 	if (c != '\0' && (!isascii(c) || !isspace((unsigned char)c)))
167 		return (0);
168 	/*
169 	 * Did we get a valid digit?
170 	 */
171 	if (!digit)
172 		return (0);
173 	/*
174 	 * Concoct the address according to
175 	 * the number of parts specified.
176 	 */
177 	n = pp - parts + 1;
178 	switch (n) {
179 	case 1:				/*%< a -- 32 bits */
180 		break;
181 
182 	case 2:				/*%< a.b -- 8.24 bits */
183 		if (val > 0xffffffU)
184 			return (0);
185 		val |= parts[0] << 24;
186 		break;
187 
188 	case 3:				/*%< a.b.c -- 8.8.16 bits */
189 		if (val > 0xffffU)
190 			return (0);
191 		val |= (parts[0] << 24) | (parts[1] << 16);
192 		break;
193 
194 	case 4:				/*%< a.b.c.d -- 8.8.8.8 bits */
195 		if (val > 0xffU)
196 			return (0);
197 		val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
198 		break;
199 	}
200 	if (addr != NULL)
201 		addr->s_addr = htonl(val);
202 	return (1);
203 }
204 
205 /*
206  * Weak aliases for applications that use certain private entry points,
207  * and fail to include <arpa/inet.h>.
208  */
209 #undef inet_addr
210 __weak_reference(__inet_addr, inet_addr);
211 #undef inet_aton
212 __weak_reference(__inet_aton, inet_aton);
213 
214 /*! \file */
215