1 /* $OpenBSD: inet_addr.c,v 1.10 2013/11/24 23:51:28 deraadt 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 <sys/param.h>
56 #include <netinet/in.h>
57 #include <arpa/inet.h>
58 #include <ctype.h>
59
60 /*
61 * Ascii internet address interpretation routine.
62 * The value returned is in network order.
63 */
64 in_addr_t
inet_addr(const char * cp)65 inet_addr(const char *cp)
66 {
67 struct in_addr val;
68
69 if (inet_aton(cp, &val))
70 return (val.s_addr);
71 return (INADDR_NONE);
72 }
73
74 /*
75 * Check whether "cp" is a valid ascii representation
76 * of an Internet address and convert to a binary address.
77 * Returns 1 if the address is valid, 0 if not.
78 * This replaces inet_addr, the return value from which
79 * cannot distinguish between failure and a local broadcast address.
80 */
81 int
inet_aton(const char * cp,struct in_addr * addr)82 inet_aton(const char *cp, struct in_addr *addr)
83 {
84 in_addr_t val;
85 int base, n;
86 char c;
87 u_int parts[4];
88 u_int *pp = parts;
89
90 c = *cp;
91 for (;;) {
92 /*
93 * Collect number up to ``.''.
94 * Values are specified as for C:
95 * 0x=hex, 0=octal, isdigit=decimal.
96 */
97 if (!isdigit((unsigned char)c))
98 return (0);
99 val = 0; base = 10;
100 if (c == '0') {
101 c = *++cp;
102 if (c == 'x' || c == 'X')
103 base = 16, c = *++cp;
104 else
105 base = 8;
106 }
107 for (;;) {
108 if (isascii((unsigned char)c) &&
109 isdigit((unsigned char)c)) {
110 val = (val * base) + (c - '0');
111 c = *++cp;
112 } else if (base == 16 &&
113 isascii((unsigned char)c) &&
114 isxdigit((unsigned char)c)) {
115 val = (val << 4) |
116 (c + 10 - (islower((unsigned char)c) ? 'a' : 'A'));
117 c = *++cp;
118 } else
119 break;
120 }
121 if (c == '.') {
122 /*
123 * Internet format:
124 * a.b.c.d
125 * a.b.c (with c treated as 16 bits)
126 * a.b (with b treated as 24 bits)
127 */
128 if (pp >= parts + 3)
129 return (0);
130 *pp++ = val;
131 c = *++cp;
132 } else
133 break;
134 }
135 /*
136 * Check for trailing characters.
137 */
138 if (c != '\0' &&
139 (!isascii((unsigned char)c) || !isspace((unsigned char)c)))
140 return (0);
141 /*
142 * Concoct the address according to
143 * the number of parts specified.
144 */
145 n = pp - parts + 1;
146 switch (n) {
147
148 case 0:
149 return (0); /* initial nondigit */
150
151 case 1: /* a -- 32 bits */
152 break;
153
154 case 2: /* a.b -- 8.24 bits */
155 if ((val > 0xffffff) || (parts[0] > 0xff))
156 return (0);
157 val |= parts[0] << 24;
158 break;
159
160 case 3: /* a.b.c -- 8.8.16 bits */
161 if ((val > 0xffff) || (parts[0] > 0xff) || (parts[1] > 0xff))
162 return (0);
163 val |= (parts[0] << 24) | (parts[1] << 16);
164 break;
165
166 case 4: /* a.b.c.d -- 8.8.8.8 bits */
167 if ((val > 0xff) || (parts[0] > 0xff) || (parts[1] > 0xff) || (parts[2] > 0xff))
168 return (0);
169 val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
170 break;
171 }
172 if (addr)
173 addr->s_addr = htonl(val);
174 return (1);
175 }
176