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 */
63 in_addr_t
inet_addr(const char * cp)64 inet_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 */
80 int
inet_aton(const char * cp,struct in_addr * addr)81 inet_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 }
175 DEF_WEAK(inet_aton);
176