xref: /freebsd/lib/libc/inet/inet_addr.c (revision 6137b5f7b8c183ee8806d79b3f1d8e5e3ddb3df3)
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 #include "port_before.h"
70 
71 #include <sys/param.h>
72 
73 #include <netinet/in.h>
74 #include <arpa/inet.h>
75 
76 #include <ctype.h>
77 
78 #include "port_after.h"
79 
80 /*%
81  * Ascii internet address interpretation routine.
82  * The value returned is in network order.
83  */
84 in_addr_t		/* XXX should be struct in_addr :( */
85 inet_addr(const char *cp) {
86 	struct in_addr val;
87 
88 	if (inet_aton(cp, &val))
89 		return (val.s_addr);
90 	return (INADDR_NONE);
91 }
92 
93 /*%
94  * Check whether "cp" is a valid ascii representation
95  * of an Internet address and convert to a binary address.
96  * Returns 1 if the address is valid, 0 if not.
97  * This replaces inet_addr, the return value from which
98  * cannot distinguish between failure and a local broadcast address.
99  */
100 int
101 inet_aton(const char *cp, struct in_addr *addr) {
102 	u_long val;
103 	int base, n;
104 	char c;
105 	u_int8_t parts[4];
106 	u_int8_t *pp = parts;
107 	int digit;
108 
109 	c = *cp;
110 	for (;;) {
111 		/*
112 		 * Collect number up to ``.''.
113 		 * Values are specified as for C:
114 		 * 0x=hex, 0=octal, isdigit=decimal.
115 		 */
116 		if (!isdigit((unsigned char)c))
117 			return (0);
118 		val = 0; base = 10; digit = 0;
119 		if (c == '0') {
120 			c = *++cp;
121 			if (c == 'x' || c == 'X')
122 				base = 16, c = *++cp;
123 			else {
124 				base = 8;
125 				digit = 1 ;
126 			}
127 		}
128 		for (;;) {
129 			if (isascii(c) && isdigit((unsigned char)c)) {
130 				if (base == 8 && (c == '8' || c == '9'))
131 					return (0);
132 				val = (val * base) + (c - '0');
133 				c = *++cp;
134 				digit = 1;
135 			} else if (base == 16 && isascii(c) &&
136 				   isxdigit((unsigned char)c)) {
137 				val = (val << 4) |
138 					(c + 10 - (islower((unsigned char)c) ? 'a' : 'A'));
139 				c = *++cp;
140 				digit = 1;
141 			} else
142 				break;
143 		}
144 		if (c == '.') {
145 			/*
146 			 * Internet format:
147 			 *	a.b.c.d
148 			 *	a.b.c	(with c treated as 16 bits)
149 			 *	a.b	(with b treated as 24 bits)
150 			 */
151 			if (pp >= parts + 3 || val > 0xffU)
152 				return (0);
153 			*pp++ = val;
154 			c = *++cp;
155 		} else
156 			break;
157 	}
158 	/*
159 	 * Check for trailing characters.
160 	 */
161 	if (c != '\0' && (!isascii(c) || !isspace((unsigned char)c)))
162 		return (0);
163 	/*
164 	 * Did we get a valid digit?
165 	 */
166 	if (!digit)
167 		return (0);
168 	/*
169 	 * Concoct the address according to
170 	 * the number of parts specified.
171 	 */
172 	n = pp - parts + 1;
173 	switch (n) {
174 	case 1:				/*%< a -- 32 bits */
175 		break;
176 
177 	case 2:				/*%< a.b -- 8.24 bits */
178 		if (val > 0xffffffU)
179 			return (0);
180 		val |= (uint32_t)parts[0] << 24;
181 		break;
182 
183 	case 3:				/*%< a.b.c -- 8.8.16 bits */
184 		if (val > 0xffffU)
185 			return (0);
186 		val |= ((uint32_t)parts[0] << 24) | (parts[1] << 16);
187 		break;
188 
189 	case 4:				/*%< a.b.c.d -- 8.8.8.8 bits */
190 		if (val > 0xffU)
191 			return (0);
192 		val |= ((uint32_t)parts[0] << 24) | (parts[1] << 16) |
193 		    (parts[2] << 8);
194 		break;
195 	}
196 	if (addr != NULL)
197 		addr->s_addr = htonl(val);
198 	return (1);
199 }
200 
201 /*
202  * Weak aliases for applications that use certain private entry points,
203  * and fail to include <arpa/inet.h>.
204  */
205 #undef inet_addr
206 __weak_reference(__inet_addr, inet_addr);
207 #undef inet_aton
208 __weak_reference(__inet_aton, inet_aton);
209 
210 /*! \file */
211