xref: /freebsd-13.1/contrib/ntp/lib/isc/inet_aton.c (revision 3311ff84)
1 /*
2  * Portions Copyright (C) 2004, 2005, 2007, 2008  Internet Systems Consortium, Inc. ("ISC")
3  * Portions Copyright (C) 1996-2001  Internet Software Consortium.
4  *
5  * Permission to use, copy, modify, and/or distribute this software for any
6  * purpose with or without fee is hereby granted, provided that the above
7  * copyright notice and this permission notice appear in all copies.
8  *
9  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
10  * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
11  * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
12  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
13  * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
14  * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
15  * PERFORMANCE OF THIS SOFTWARE.
16  */
17 
18 /*
19  * Copyright (c) 1983, 1990, 1993
20  *    The Regents of the University of California.  All rights reserved.
21  *
22  * Redistribution and use in source and binary forms, with or without
23  * modification, are permitted provided that the following conditions
24  * are met:
25  * 1. Redistributions of source code must retain the above copyright
26  *    notice, this list of conditions and the following disclaimer.
27  * 2. Redistributions in binary form must reproduce the above copyright
28  *    notice, this list of conditions and the following disclaimer in the
29  *    documentation and/or other materials provided with the distribution.
30  * 3. All advertising materials mentioning features or use of this software
31  *    must display the following acknowledgement:
32  * 	This product includes software developed by the University of
33  * 	California, Berkeley and its contributors.
34  * 4. Neither the name of the University nor the names of its contributors
35  *    may be used to endorse or promote products derived from this software
36  *    without specific prior written permission.
37  *
38  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
39  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
40  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
41  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
42  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
43  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
44  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
45  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
46  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
47  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
48  * SUCH DAMAGE.
49  */
50 
51 /*
52  * Portions Copyright (c) 1993 by Digital Equipment Corporation.
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, and that
57  * the name of Digital Equipment Corporation not be used in advertising or
58  * publicity pertaining to distribution of the document or software without
59  * specific, written prior permission.
60  *
61  * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
62  * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
63  * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
64  * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
65  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
66  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
67  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
68  * SOFTWARE.
69  */
70 /*! \file */
71 
72 #if defined(LIBC_SCCS) && !defined(lint)
73 static char sccsid[] = "@(#)inet_addr.c	8.1 (Berkeley) 6/17/93";
74 static char rcsid[] = "$Id: inet_aton.c,v 1.23 2008/12/01 23:47:45 tbox Exp $";
75 #endif /* LIBC_SCCS and not lint */
76 
77 #include <config.h>
78 
79 #include <ctype.h>
80 #include <stddef.h>		/* Required for NULL. */
81 
82 #include <isc/types.h>
83 #include <isc/net.h>
84 
85 /*%
86  * Check whether "cp" is a valid ascii representation
87  * of an Internet address and convert to a binary address.
88  * Returns 1 if the address is valid, 0 if not.
89  * This replaces inet_addr, the return value from which
90  * cannot distinguish between failure and a local broadcast address.
91  */
92 int
isc_net_aton(const char * cp,struct in_addr * addr)93 isc_net_aton(const char *cp, struct in_addr *addr) {
94 	unsigned long val;
95 	int base;
96 	unsigned char c;
97 	isc_uint8_t parts[4];
98 	isc_uint8_t *pp = parts;
99 	int digit;
100 
101 	c = *cp;
102 	for (;;) {
103 		/*
104 		 * Collect number up to ``.''.
105 		 * Values are specified as for C:
106 		 * 0x=hex, 0=octal, isdigit=decimal.
107 		 */
108 		if (!isdigit(c & 0xff))
109 			return (0);
110 		val = 0; base = 10; digit = 0;
111 		if (c == '0') {
112 			c = *++cp;
113 			if (c == 'x' || c == 'X')
114 				base = 16, c = *++cp;
115 			else {
116 				base = 8;
117 				digit = 1;
118 			}
119 		}
120 		for (;;) {
121 			/*
122 			 * isascii() is valid for all integer values, and
123 			 * when it is true, c is known to be in scope
124 			 * for isdigit().  No cast necessary.  Similar
125 			 * comment applies for later ctype uses.
126 			 */
127 			if (isascii(c) && isdigit(c)) {
128 				if (base == 8 && (c == '8' || c == '9'))
129 					return (0);
130 				val = (val * base) + (c - '0');
131 				c = *++cp;
132 				digit = 1;
133 			} else if (base == 16 && isascii(c) && isxdigit(c)) {
134 				val = (val << 4) |
135 					(c + 10 - (islower(c) ? 'a' : 'A'));
136 				c = *++cp;
137 				digit = 1;
138 			} else
139 				break;
140 		}
141 		if (c == '.') {
142 			/*
143 			 * Internet format:
144 			 *	a.b.c.d
145 			 *	a.b.c	(with c treated as 16 bits)
146 			 *	a.b	(with b treated as 24 bits)
147 			 */
148 			if (pp >= parts + 3 || val > 0xffU)
149 				return (0);
150 			*pp++ = (isc_uint8_t)val;
151 			c = *++cp;
152 		} else
153 			break;
154 	}
155 	/*
156 	 * Check for trailing characters.
157 	 */
158 	if (c != '\0' && (!isascii(c) || !isspace(c)))
159 		return (0);
160 	/*
161 	 * Did we get a valid digit?
162 	 */
163 	if (!digit)
164 		return (0);
165 	/*
166 	 * Concoct the address according to
167 	 * the number of parts specified.
168 	 */
169 	switch (pp - parts + 1) {
170 	case 1:				/* a -- 32 bits */
171 		break;
172 
173 	case 2:				/* a.b -- 8.24 bits */
174 		if (val > 0xffffffU)
175 			return (0);
176 		val |= parts[0] << 24;
177 		break;
178 
179 	case 3:				/* a.b.c -- 8.8.16 bits */
180 		if (val > 0xffffU)
181 			return (0);
182 		val |= (parts[0] << 24) | (parts[1] << 16);
183 		break;
184 
185 	case 4:				/* a.b.c.d -- 8.8.8.8 bits */
186 		if (val > 0xffU)
187 			return (0);
188 		val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
189 		break;
190 	}
191 	if (addr != NULL)
192 		addr->s_addr = htonl(val);
193 
194 	return (1);
195 }
196