xref: /netbsd-src/external/bsd/nsd/dist/compat/inet_aton.c (revision d83a80ee7fb31190352cf1f781441e06ca6a86db)
1 /* From openssh4.3p2 compat/inet_aton.c */
2 /*
3  * Copyright (c) 1983, 1990, 1993
4  *    The Regents of the University of California.  All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. Neither the name of the University nor the names of its contributors
15  *    may be used to endorse or promote products derived from this software
16  *    without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  * -
30  * Portions Copyright (c) 1993 by Digital Equipment Corporation.
31  *
32  * Permission to use, copy, modify, and distribute this software for any
33  * purpose with or without fee is hereby granted, provided that the above
34  * copyright notice and this permission notice appear in all copies, and that
35  * the name of Digital Equipment Corporation not be used in advertising or
36  * publicity pertaining to distribution of the document or software without
37  * specific, written prior permission.
38  *
39  * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
40  * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
41  * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
42  * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
43  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
44  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
45  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
46  * SOFTWARE.
47  * -
48  * --Copyright--
49  */
50 
51 /* OPENBSD ORIGINAL: lib/libc/net/inet_addr.c */
52 
53 #include <config.h>
54 
55 #if !defined(HAVE_INET_ATON)
56 
57 #include <sys/types.h>
58 #include <sys/param.h>
59 #include <netinet/in.h>
60 #include <arpa/inet.h>
61 #include <ctype.h>
62 
63 #if 0
64 /*
65  * Ascii internet address interpretation routine.
66  * The value returned is in network order.
67  */
68 in_addr_t
69 inet_addr(const char *cp)
70 {
71 	struct in_addr val;
72 
73 	if (inet_aton(cp, &val))
74 		return (val.s_addr);
75 	return (INADDR_NONE);
76 }
77 #endif
78 
79 /*
80  * Check whether "cp" is a valid ascii representation
81  * of an Internet address and convert to a binary address.
82  * Returns 1 if the address is valid, 0 if not.
83  * This replaces inet_addr, the return value from which
84  * cannot distinguish between failure and a local broadcast address.
85  */
86 int
inet_aton(const char * cp,struct in_addr * addr)87 inet_aton(const char *cp, struct in_addr *addr)
88 {
89 	uint32_t val;
90 	int base, n;
91 	char c;
92 	unsigned int parts[4];
93 	unsigned int *pp = parts;
94 
95 	c = *cp;
96 	for (;;) {
97 		/*
98 		 * Collect number up to ``.''.
99 		 * Values are specified as for C:
100 		 * 0x=hex, 0=octal, isdigit=decimal.
101 		 */
102 		if (!isdigit((unsigned char)c))
103 			return (0);
104 		val = 0; base = 10;
105 		if (c == '0') {
106 			c = *++cp;
107 			if (c == 'x' || c == 'X')
108 				base = 16, c = *++cp;
109 			else
110 				base = 8;
111 		}
112 		for (;;) {
113 			if (isascii((unsigned char)c) && isdigit((unsigned char)c)) {
114 				val = (val * base) + (c - '0');
115 				c = *++cp;
116 			} else if (base == 16 && isascii((unsigned char)c) && isxdigit((unsigned char)c)) {
117 				val = (val << 4) |
118 					(c + 10 - (islower((unsigned char)c) ? 'a' : 'A'));
119 				c = *++cp;
120 			} else
121 				break;
122 		}
123 		if (c == '.') {
124 			/*
125 			 * Internet format:
126 			 *	a.b.c.d
127 			 *	a.b.c	(with c treated as 16 bits)
128 			 *	a.b	(with b treated as 24 bits)
129 			 */
130 			if (pp >= parts + 3)
131 				return (0);
132 			*pp++ = val;
133 			c = *++cp;
134 		} else
135 			break;
136 	}
137 	/*
138 	 * Check for trailing characters.
139 	 */
140 	if (c != '\0' && (!isascii((unsigned char)c) || !isspace((unsigned char)c)))
141 		return (0);
142 	/*
143 	 * Concoct the address according to
144 	 * the number of parts specified.
145 	 */
146 	n = pp - parts + 1;
147 	switch (n) {
148 
149 	case 0:
150 		return (0);		/* initial nondigit */
151 
152 	case 1:				/* a -- 32 bits */
153 		break;
154 
155 	case 2:				/* a.b -- 8.24 bits */
156 		if ((val > 0xffffff) || (parts[0] > 0xff))
157 			return (0);
158 		val |= parts[0] << 24;
159 		break;
160 
161 	case 3:				/* a.b.c -- 8.8.16 bits */
162 		if ((val > 0xffff) || (parts[0] > 0xff) || (parts[1] > 0xff))
163 			return (0);
164 		val |= (parts[0] << 24) | (parts[1] << 16);
165 		break;
166 
167 	case 4:				/* a.b.c.d -- 8.8.8.8 bits */
168 		if ((val > 0xff) || (parts[0] > 0xff) || (parts[1] > 0xff) || (parts[2] > 0xff))
169 			return (0);
170 		val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
171 		break;
172 	}
173 	if (addr)
174 		addr->s_addr = htonl(val);
175 	return (1);
176 }
177 
178 #endif /* !defined(HAVE_INET_ATON) */
179