1/*	$OpenBSD: inet_addr.c,v 1.12 2015/09/13 21:36:08 guenther Exp $	*/
2
3/*
4 * ++Copyright++ 1983, 1990, 1993
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 * 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 * --Copyright--
52 */
53
54#include <sys/types.h>
55#include <netinet/in.h>
56#include <arpa/inet.h>
57#include <ctype.h>
58
59/*
60 * Ascii internet address interpretation routine.
61 * The value returned is in network order.
62 */
63in_addr_t
64inet_addr(const char *cp)
65{
66	struct in_addr val;
67
68	if (inet_aton(cp, &val))
69		return (val.s_addr);
70	return (INADDR_NONE);
71}
72
73/*
74 * Check whether "cp" is a valid ascii representation
75 * of an Internet address and convert to a binary address.
76 * Returns 1 if the address is valid, 0 if not.
77 * This replaces inet_addr, the return value from which
78 * cannot distinguish between failure and a local broadcast address.
79 */
80int
81inet_aton(const char *cp, struct in_addr *addr)
82{
83	in_addr_t val;
84	int base, n;
85	char c;
86	u_int parts[4];
87	u_int *pp = parts;
88
89	c = *cp;
90	for (;;) {
91		/*
92		 * Collect number up to ``.''.
93		 * Values are specified as for C:
94		 * 0x=hex, 0=octal, isdigit=decimal.
95		 */
96		if (!isdigit((unsigned char)c))
97			return (0);
98		val = 0; base = 10;
99		if (c == '0') {
100			c = *++cp;
101			if (c == 'x' || c == 'X')
102				base = 16, c = *++cp;
103			else
104				base = 8;
105		}
106		for (;;) {
107			if (isascii((unsigned char)c) &&
108			    isdigit((unsigned char)c)) {
109				val = (val * base) + (c - '0');
110				c = *++cp;
111			} else if (base == 16 &&
112			    isascii((unsigned char)c) &&
113			    isxdigit((unsigned char)c)) {
114				val = (val << 4) |
115				    (c + 10 - (islower((unsigned char)c) ? 'a' : 'A'));
116				c = *++cp;
117			} else
118				break;
119		}
120		if (c == '.') {
121			/*
122			 * Internet format:
123			 *	a.b.c.d
124			 *	a.b.c	(with c treated as 16 bits)
125			 *	a.b	(with b treated as 24 bits)
126			 */
127			if (pp >= parts + 3)
128				return (0);
129			*pp++ = val;
130			c = *++cp;
131		} else
132			break;
133	}
134	/*
135	 * Check for trailing characters.
136	 */
137	if (c != '\0' &&
138	    (!isascii((unsigned char)c) || !isspace((unsigned char)c)))
139		return (0);
140	/*
141	 * Concoct the address according to
142	 * the number of parts specified.
143	 */
144	n = pp - parts + 1;
145	switch (n) {
146
147	case 0:
148		return (0);		/* initial nondigit */
149
150	case 1:				/* a -- 32 bits */
151		break;
152
153	case 2:				/* a.b -- 8.24 bits */
154		if ((val > 0xffffff) || (parts[0] > 0xff))
155			return (0);
156		val |= parts[0] << 24;
157		break;
158
159	case 3:				/* a.b.c -- 8.8.16 bits */
160		if ((val > 0xffff) || (parts[0] > 0xff) || (parts[1] > 0xff))
161			return (0);
162		val |= (parts[0] << 24) | (parts[1] << 16);
163		break;
164
165	case 4:				/* a.b.c.d -- 8.8.8.8 bits */
166		if ((val > 0xff) || (parts[0] > 0xff) || (parts[1] > 0xff) || (parts[2] > 0xff))
167			return (0);
168		val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
169		break;
170	}
171	if (addr)
172		addr->s_addr = htonl(val);
173	return (1);
174}
175DEF_WEAK(inet_aton);
176