1/*-
2 * Copyright (c) 2001 Charles Mott <cm@linktel.net>
3 * 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 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26#include <sys/param.h>
27#include <sys/systm.h>
28
29#include <netinet/in.h>
30
31/* XXX ctype.h is missing, see libkern/stdio/scanf.c */
32#if 1
33static inline int
34isspace(char c)
35{
36        return (c == ' ' || c == '\t' || c == '\n' || c == '\12');
37}
38#endif
39
40int
41inet_aton(const char *cp, struct in_addr *addr)
42{
43	u_long parts[4];
44	in_addr_t val;
45	const char *c;
46	char *endptr;
47	int gotend, n;
48
49	c = (const char *)cp;
50	n = 0;
51
52	/*
53	 * Run through the string, grabbing numbers until
54	 * the end of the string, or some error
55	 */
56	gotend = 0;
57	while (!gotend) {
58		unsigned long l;
59
60		l = strtoul(c, &endptr, 0);
61
62		if (l == ULONG_MAX || (l == 0 && endptr == c))
63			return (0);
64
65		val = (in_addr_t)l;
66
67		/*
68		 * If the whole string is invalid, endptr will equal
69		 * c.. this way we can make sure someone hasn't
70		 * gone '.12' or something which would get past
71		 * the next check.
72		 */
73		if (endptr == c)
74			return (0);
75		parts[n] = val;
76		c = endptr;
77
78		/* Check the next character past the previous number's end */
79		switch (*c) {
80		case '.' :
81
82			/* Make sure we only do 3 dots .. */
83			if (n == 3)	/* Whoops. Quit. */
84				return (0);
85			n++;
86			c++;
87			break;
88
89		case '\0':
90			gotend = 1;
91			break;
92
93		default:
94			if (isspace((unsigned char)*c)) {
95				gotend = 1;
96				break;
97			} else {
98
99				/* Invalid character, then fail. */
100				return (0);
101			}
102		}
103
104	}
105
106	/* Concoct the address according to the number of parts specified. */
107	switch (n) {
108	case 0:				/* a -- 32 bits */
109
110		/*
111		 * Nothing is necessary here.  Overflow checking was
112		 * already done in strtoul().
113		 */
114		break;
115	case 1:				/* a.b -- 8.24 bits */
116		if (val > 0xffffff || parts[0] > 0xff)
117			return (0);
118		val |= parts[0] << 24;
119		break;
120
121	case 2:				/* a.b.c -- 8.8.16 bits */
122		if (val > 0xffff || parts[0] > 0xff || parts[1] > 0xff)
123			return (0);
124		val |= (parts[0] << 24) | (parts[1] << 16);
125		break;
126
127	case 3:				/* a.b.c.d -- 8.8.8.8 bits */
128		if (val > 0xff || parts[0] > 0xff || parts[1] > 0xff ||
129		    parts[2] > 0xff)
130			return (0);
131		val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
132		break;
133	}
134
135	if (addr != NULL)
136		addr->s_addr = htonl(val);
137	return (1);
138}
139