xref: /netbsd-src/external/mpl/dhcp/dist/omapip/inet_addr.c (revision ce893c7eea48d62b6f0d8ef9958789ad27d03f6f)
1 /*	$NetBSD: inet_addr.c,v 1.2 2018/04/07 22:37:30 christos Exp $	*/
2 
3 /*	NetBSD: inet_addr.c,v 1.6 1996/02/02 15:22:23 mrg Exp 	*/
4 
5 /*
6  * Copyright (c) 1983, 1990, 1993
7  *	The Regents of the University of California.  All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #include <sys/cdefs.h>
35 __RCSID("$NetBSD: inet_addr.c,v 1.2 2018/04/07 22:37:30 christos Exp $");
36 
37 
38 #include "dhcpd.h"
39 
40 #include "omapip/omapip_p.h"
41 
42 #ifdef NEED_INET_ATON
43 /*
44  * Check whether "cp" is a valid ascii representation
45  * of an Internet address and convert to a binary address.
46  * Returns 1 if the address is valid, 0 if not.
47  * This replaces inet_addr, the return value from which
48  * cannot distinguish between failure and a local broadcast address.
49  */
50 int
inet_aton(cp,addr)51 inet_aton(cp, addr)
52 	const char *cp;
53 	struct in_addr *addr;
54 {
55 	register u_long val;
56 	register int base, n;
57 	register char c;
58 	u_int parts[4];
59 	register u_int *pp = parts;
60 
61 	for (;;) {
62 		/*
63 		 * Collect number up to ``.''.
64 		 * Values are specified as for C:
65 		 * 0x=hex, 0=octal, other=decimal.
66 		 */
67 		val = 0; base = 10;
68 		if (*cp == '0') {
69 			if (*++cp == 'x' || *cp == 'X')
70 				base = 16, cp++;
71 			else
72 				base = 8;
73 		}
74 		while ((c = *cp) != '\0') {
75 			if (isascii(c) && isdigit((int)c)) {
76 				val = (val * base) + (c - '0');
77 				cp++;
78 				continue;
79 			}
80 			if (base == 16 && isascii(c) && isxdigit((int)c)) {
81 				val = (val << 4) +
82 				      (c + 10 - (islower((int)c) ? 'a' : 'A'));
83 				cp++;
84 				continue;
85 			}
86 			break;
87 		}
88 		if (*cp == '.') {
89 			/*
90 			 * Internet format:
91 			 *	a.b.c.d
92 			 *	a.b.c	(with c treated as 16-bits)
93 			 *	a.b	(with b treated as 24 bits)
94 			 */
95 			if (pp >= parts + 3 || val > 0xff)
96 				return (0);
97 			*pp++ = val, cp++;
98 		} else
99 			break;
100 	}
101 	/*
102 	 * Check for trailing characters.
103 	 */
104 	if (*cp && (!isascii(*cp) || !isspace((int)*cp)))
105 		return (0);
106 	/*
107 	 * Concoct the address according to
108 	 * the number of parts specified.
109 	 */
110 	n = pp - parts + 1;
111 	switch (n) {
112 
113 	case 0:
114 		return (0);		/* initial nondigit */
115 
116 	case 1:				/* a -- 32 bits */
117 		break;
118 
119 	case 2:				/* a.b -- 8.24 bits */
120 		if (val > 0xffffff)
121 			return (0);
122 		val |= parts[0] << 24;
123 		break;
124 
125 	case 3:				/* a.b.c -- 8.8.16 bits */
126 		if (val > 0xffff)
127 			return (0);
128 		val |= (parts[0] << 24) | (parts[1] << 16);
129 		break;
130 
131 	case 4:				/* a.b.c.d -- 8.8.8.8 bits */
132 		if (val > 0xff)
133 			return (0);
134 		val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
135 		break;
136 	}
137 	if (addr)
138 		addr->s_addr = htonl(val);
139 	return (1);
140 }
141 #endif
142