xref: /freebsd/lib/libc/inet/inet_addr.c (revision 7431dfd4580e850375fe5478d92ec770344db098)
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/types.h>
77 #include <sys/param.h>
78 
79 #include <netinet/in.h>
80 #include <arpa/inet.h>
81 
82 #include <ctype.h>
83 
84 #include "port_after.h"
85 
86 /*%
87  * Ascii internet address interpretation routine.
88  * The value returned is in network order.
89  */
90 in_addr_t		/* XXX should be struct in_addr :( */
91 inet_addr(const char *cp) {
92 	struct in_addr val;
93 
94 	if (inet_aton(cp, &val))
95 		return (val.s_addr);
96 	return (INADDR_NONE);
97 }
98 
99 /*%
100  * Check whether "cp" is a valid ascii representation
101  * of an Internet address and convert to a binary address.
102  * Returns 1 if the address is valid, 0 if not.
103  * This replaces inet_addr, the return value from which
104  * cannot distinguish between failure and a local broadcast address.
105  */
106 int
107 inet_aton(const char *cp, struct in_addr *addr) {
108 	u_long val;
109 	int base, n;
110 	char c;
111 	u_int8_t parts[4];
112 	u_int8_t *pp = parts;
113 	int digit;
114 
115 	c = *cp;
116 	for (;;) {
117 		/*
118 		 * Collect number up to ``.''.
119 		 * Values are specified as for C:
120 		 * 0x=hex, 0=octal, isdigit=decimal.
121 		 */
122 		if (!isdigit((unsigned char)c))
123 			return (0);
124 		val = 0; base = 10; digit = 0;
125 		if (c == '0') {
126 			c = *++cp;
127 			if (c == 'x' || c == 'X')
128 				base = 16, c = *++cp;
129 			else {
130 				base = 8;
131 				digit = 1 ;
132 			}
133 		}
134 		for (;;) {
135 			if (isascii(c) && isdigit((unsigned char)c)) {
136 				if (base == 8 && (c == '8' || c == '9'))
137 					return (0);
138 				val = (val * base) + (c - '0');
139 				c = *++cp;
140 				digit = 1;
141 			} else if (base == 16 && isascii(c) &&
142 				   isxdigit((unsigned char)c)) {
143 				val = (val << 4) |
144 					(c + 10 - (islower((unsigned char)c) ? 'a' : 'A'));
145 				c = *++cp;
146 				digit = 1;
147 			} else
148 				break;
149 		}
150 		if (c == '.') {
151 			/*
152 			 * Internet format:
153 			 *	a.b.c.d
154 			 *	a.b.c	(with c treated as 16 bits)
155 			 *	a.b	(with b treated as 24 bits)
156 			 */
157 			if (pp >= parts + 3 || val > 0xffU)
158 				return (0);
159 			*pp++ = val;
160 			c = *++cp;
161 		} else
162 			break;
163 	}
164 	/*
165 	 * Check for trailing characters.
166 	 */
167 	if (c != '\0' && (!isascii(c) || !isspace((unsigned char)c)))
168 		return (0);
169 	/*
170 	 * Did we get a valid digit?
171 	 */
172 	if (!digit)
173 		return (0);
174 	/*
175 	 * Concoct the address according to
176 	 * the number of parts specified.
177 	 */
178 	n = pp - parts + 1;
179 	switch (n) {
180 	case 1:				/*%< a -- 32 bits */
181 		break;
182 
183 	case 2:				/*%< a.b -- 8.24 bits */
184 		if (val > 0xffffffU)
185 			return (0);
186 		val |= parts[0] << 24;
187 		break;
188 
189 	case 3:				/*%< a.b.c -- 8.8.16 bits */
190 		if (val > 0xffffU)
191 			return (0);
192 		val |= (parts[0] << 24) | (parts[1] << 16);
193 		break;
194 
195 	case 4:				/*%< a.b.c.d -- 8.8.8.8 bits */
196 		if (val > 0xffU)
197 			return (0);
198 		val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
199 		break;
200 	}
201 	if (addr != NULL)
202 		addr->s_addr = htonl(val);
203 	return (1);
204 }
205 
206 /*
207  * Weak aliases for applications that use certain private entry points,
208  * and fail to include <arpa/inet.h>.
209  */
210 #undef inet_addr
211 __weak_reference(__inet_addr, inet_addr);
212 #undef inet_aton
213 __weak_reference(__inet_aton, inet_aton);
214 
215 /*! \file */
216