xref: /freebsd/lib/libc/inet/inet_addr.c (revision 1a498d2e689f9e8220e2ad64b018eb1f0d11127e)
1 /*-
2  * SPDX-License-Identifier: (BSD-3-Clause AND ISC)
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 
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 
52 /*
53  * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
54  * Portions Copyright (c) 1996-1999 by Internet Software Consortium.
55  *
56  * Permission to use, copy, modify, and distribute this software for any
57  * purpose with or without fee is hereby granted, provided that the above
58  * copyright notice and this permission notice appear in all copies.
59  *
60  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
61  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
62  * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
63  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
64  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
65  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
66  * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
67  */
68 
69 #if defined(LIBC_SCCS) && !defined(lint)
70 static const char sccsid[] = "@(#)inet_addr.c	8.1 (Berkeley) 6/17/93";
71 static const char rcsid[] = "$Id: inet_addr.c,v 1.5 2005/04/27 04:56:19 sra Exp $";
72 #endif /* LIBC_SCCS and not lint */
73 #include <sys/cdefs.h>
74 __FBSDID("$FreeBSD$");
75 
76 #include "port_before.h"
77 
78 #include <sys/param.h>
79 
80 #include <netinet/in.h>
81 #include <arpa/inet.h>
82 
83 #include <ctype.h>
84 
85 #include "port_after.h"
86 
87 /*%
88  * Ascii internet address interpretation routine.
89  * The value returned is in network order.
90  */
91 in_addr_t		/* XXX should be struct in_addr :( */
92 inet_addr(const char *cp) {
93 	struct in_addr val;
94 
95 	if (inet_aton(cp, &val))
96 		return (val.s_addr);
97 	return (INADDR_NONE);
98 }
99 
100 /*%
101  * Check whether "cp" is a valid ascii representation
102  * of an Internet address and convert to a binary address.
103  * Returns 1 if the address is valid, 0 if not.
104  * This replaces inet_addr, the return value from which
105  * cannot distinguish between failure and a local broadcast address.
106  */
107 int
108 inet_aton(const char *cp, struct in_addr *addr) {
109 	u_long val;
110 	int base, n;
111 	char c;
112 	u_int8_t parts[4];
113 	u_int8_t *pp = parts;
114 	int digit;
115 
116 	c = *cp;
117 	for (;;) {
118 		/*
119 		 * Collect number up to ``.''.
120 		 * Values are specified as for C:
121 		 * 0x=hex, 0=octal, isdigit=decimal.
122 		 */
123 		if (!isdigit((unsigned char)c))
124 			return (0);
125 		val = 0; base = 10; digit = 0;
126 		if (c == '0') {
127 			c = *++cp;
128 			if (c == 'x' || c == 'X')
129 				base = 16, c = *++cp;
130 			else {
131 				base = 8;
132 				digit = 1 ;
133 			}
134 		}
135 		for (;;) {
136 			if (isascii(c) && isdigit((unsigned char)c)) {
137 				if (base == 8 && (c == '8' || c == '9'))
138 					return (0);
139 				val = (val * base) + (c - '0');
140 				c = *++cp;
141 				digit = 1;
142 			} else if (base == 16 && isascii(c) &&
143 				   isxdigit((unsigned char)c)) {
144 				val = (val << 4) |
145 					(c + 10 - (islower((unsigned char)c) ? 'a' : 'A'));
146 				c = *++cp;
147 				digit = 1;
148 			} else
149 				break;
150 		}
151 		if (c == '.') {
152 			/*
153 			 * Internet format:
154 			 *	a.b.c.d
155 			 *	a.b.c	(with c treated as 16 bits)
156 			 *	a.b	(with b treated as 24 bits)
157 			 */
158 			if (pp >= parts + 3 || val > 0xffU)
159 				return (0);
160 			*pp++ = val;
161 			c = *++cp;
162 		} else
163 			break;
164 	}
165 	/*
166 	 * Check for trailing characters.
167 	 */
168 	if (c != '\0' && (!isascii(c) || !isspace((unsigned char)c)))
169 		return (0);
170 	/*
171 	 * Did we get a valid digit?
172 	 */
173 	if (!digit)
174 		return (0);
175 	/*
176 	 * Concoct the address according to
177 	 * the number of parts specified.
178 	 */
179 	n = pp - parts + 1;
180 	switch (n) {
181 	case 1:				/*%< a -- 32 bits */
182 		break;
183 
184 	case 2:				/*%< a.b -- 8.24 bits */
185 		if (val > 0xffffffU)
186 			return (0);
187 		val |= (uint32_t)parts[0] << 24;
188 		break;
189 
190 	case 3:				/*%< a.b.c -- 8.8.16 bits */
191 		if (val > 0xffffU)
192 			return (0);
193 		val |= ((uint32_t)parts[0] << 24) | (parts[1] << 16);
194 		break;
195 
196 	case 4:				/*%< a.b.c.d -- 8.8.8.8 bits */
197 		if (val > 0xffU)
198 			return (0);
199 		val |= ((uint32_t)parts[0] << 24) | (parts[1] << 16) |
200 		    (parts[2] << 8);
201 		break;
202 	}
203 	if (addr != NULL)
204 		addr->s_addr = htonl(val);
205 	return (1);
206 }
207 
208 /*
209  * Weak aliases for applications that use certain private entry points,
210  * and fail to include <arpa/inet.h>.
211  */
212 #undef inet_addr
213 __weak_reference(__inet_addr, inet_addr);
214 #undef inet_aton
215 __weak_reference(__inet_aton, inet_aton);
216 
217 /*! \file */
218