xref: /openbsd-src/lib/libc/net/inet_network.c (revision db3296cf5c1dd9058ceecc3a29fe4aaa0bd26000)
1 /*
2  * Copyright (c) 1983, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #if defined(LIBC_SCCS) && !defined(lint)
31 static char rcsid[] = "$OpenBSD: inet_network.c,v 1.8 2003/06/02 20:18:35 millert Exp $";
32 #endif /* LIBC_SCCS and not lint */
33 
34 #include <sys/types.h>
35 #include <netinet/in.h>
36 #include <arpa/inet.h>
37 #include <ctype.h>
38 
39 /*
40  * Internet network address interpretation routine.
41  * The library routines call this routine to interpret
42  * network numbers.
43  */
44 in_addr_t
45 inet_network(cp)
46 	register const char *cp;
47 {
48 	register in_addr_t val, base, n;
49 	register char c;
50 	in_addr_t parts[4], *pp = parts;
51 	register int i;
52 
53 again:
54 	val = 0; base = 10;
55 	if (*cp == '0')
56 		base = 8, cp++;
57 	if (*cp == 'x' || *cp == 'X')
58 		base = 16, cp++;
59 	while ((c = *cp)) {
60 		if (isdigit(c)) {
61 			val = (val * base) + (c - '0');
62 			cp++;
63 			continue;
64 		}
65 		if (base == 16 && isxdigit(c)) {
66 			val = (val << 4) + (c + 10 - (islower(c) ? 'a' : 'A'));
67 			cp++;
68 			continue;
69 		}
70 		break;
71 	}
72 	if (*cp == '.') {
73 		if (pp >= parts + 3)
74 			return (INADDR_NONE);
75 		*pp++ = val, cp++;
76 		goto again;
77 	}
78 	if (*cp && !isspace(*cp))
79 		return (INADDR_NONE);
80 	*pp++ = val;
81 	n = pp - parts;
82 	for (val = 0, i = 0; i < 4; i++) {
83 		val <<= 8;
84 		if (i < n)
85 			val |= parts[i] & 0xff;
86 	}
87 	return (val);
88 }
89