1 /*
2 * Portions Copyright (C) Internet Systems Consortium, Inc. ("ISC")
3 *
4 * This Source Code Form is subject to the terms of the Mozilla Public
5 * License, v. 2.0. If a copy of the MPL was not distributed with this
6 * file, you can obtain one at https://mozilla.org/MPL/2.0/.
7 *
8 * See the COPYRIGHT file distributed with this work for additional
9 * information regarding copyright ownership.
10 */
11
12 /*
13 * Copyright (c) 1983, 1990, 1993
14 * The Regents of the University of California. All rights reserved.
15 *
16 * Redistribution and use in source and binary forms, with or without
17 * modification, are permitted provided that the following conditions
18 * are met:
19 * 1. Redistributions of source code must retain the above copyright
20 * notice, this list of conditions and the following disclaimer.
21 * 2. Redistributions in binary form must reproduce the above copyright
22 * notice, this list of conditions and the following disclaimer in the
23 * documentation and/or other materials provided with the distribution.
24 * 3. Neither the name of the University nor the names of its contributors
25 * may be used to endorse or promote products derived from this software
26 * without specific prior written permission.
27 *
28 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
29 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
31 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
32 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
37 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38 * SUCH DAMAGE.
39 */
40
41 /*
42 * Portions Copyright (c) 1993 by Digital Equipment Corporation.
43 *
44 * Permission to use, copy, modify, and distribute this software for any
45 * purpose with or without fee is hereby granted, provided that the above
46 * copyright notice and this permission notice appear in all copies, and that
47 * the name of Digital Equipment Corporation not be used in advertising or
48 * publicity pertaining to distribution of the document or software without
49 * specific, written prior permission.
50 *
51 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
52 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
53 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT
54 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
55 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
56 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
57 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
58 * SOFTWARE.
59 */
60
61 /*! \file lwinetaton.c
62 */
63 #if defined(LIBC_SCCS) && !defined(lint)
64 static char sccsid[] = "@(#)inet_addr.c 8.1 (Berkeley) 6/17/93";
65 #endif /* LIBC_SCCS and not lint */
66
67 #include <config.h>
68
69 #include <ctype.h>
70 #include <inttypes.h>
71 #include <stddef.h>
72
73 #include <lwres/net.h>
74
75 #include "assert_p.h"
76
77 /*!
78 * Check whether "cp" is a valid ascii representation
79 * of an Internet address and convert to a binary address.
80 * Returns 1 if the address is valid, 0 if not.
81 * This replaces inet_addr, the return value from which
82 * cannot distinguish between failure and a local broadcast address.
83 */
84 int
lwres_net_aton(const char * cp,struct in_addr * addr)85 lwres_net_aton(const char *cp, struct in_addr *addr) {
86 uint32_t val;
87 int base;
88 ptrdiff_t n;
89 unsigned char c;
90 uint8_t parts[4];
91 uint8_t *pp = parts;
92 int digit;
93
94 REQUIRE(cp != NULL);
95
96 c = *cp;
97 for (;;) {
98 /*
99 * Collect number up to ``.''.
100 * Values are specified as for C:
101 * 0x=hex, 0=octal, isdigit=decimal.
102 */
103 if (!isdigit(c & 0xff))
104 return (0);
105 val = 0;
106 base = 10;
107 digit = 0;
108 if (c == '0') {
109 c = *++cp;
110 if (c == 'x' || c == 'X') {
111 base = 16;
112 c = *++cp;
113 } else {
114 base = 8;
115 digit = 1;
116 }
117 }
118 for (;;) {
119 /*
120 * isascii() is valid for all integer values, and
121 * when it is true, c is known to be in scope
122 * for isdigit(). No cast necessary. Similar
123 * comment applies for later ctype uses.
124 */
125 if (isascii(c) && isdigit(c)) {
126 if (base == 8 && (c == '8' || c == '9'))
127 return (0);
128 val = (val * base) + (c - '0');
129 c = *++cp;
130 digit = 1;
131 } else if (base == 16 && isascii(c) && isxdigit(c)) {
132 val = (val << 4) |
133 (c + 10 - (islower(c) ? 'a' : 'A'));
134 c = *++cp;
135 digit = 1;
136 } else
137 break;
138 }
139 if (c == '.') {
140 /*
141 * Internet format:
142 * a.b.c.d
143 * a.b.c (with c treated as 16 bits)
144 * a.b (with b treated as 24 bits)
145 */
146 if (pp >= parts + 3 || val > 0xffU)
147 return (0);
148 *pp++ = (uint8_t)val;
149 c = *++cp;
150 } else
151 break;
152 }
153 /*
154 * Check for trailing characters.
155 */
156 if (c != '\0' && (!isascii(c) || !isspace(c)))
157 return (0);
158 /*
159 * Did we get a valid digit?
160 */
161 if (!digit)
162 return (0);
163 /*
164 * Concoct the address according to
165 * the number of parts specified.
166 */
167 n = pp - parts + 1;
168 switch (n) {
169 case 1: /* a -- 32 bits */
170 break;
171
172 case 2: /* a.b -- 8.24 bits */
173 if (val > 0xffffffU)
174 return (0);
175 #define ulshift(x, n) ((unsigned int)(x) << (n))
176 val |= ulshift(parts[0], 24);
177 break;
178
179 case 3: /* a.b.c -- 8.8.16 bits */
180 if (val > 0xffffU)
181 return (0);
182 val |= ulshift(parts[0], 24) | ulshift(parts[1], 16);
183 break;
184
185 case 4: /* a.b.c.d -- 8.8.8.8 bits */
186 if (val > 0xffU)
187 return (0);
188 val |= ulshift(parts[0], 24) | ulshift(parts[1], 16) |
189 ulshift(parts[2], 8);
190 break;
191 }
192 if (addr != NULL)
193 addr->s_addr = htonl(val);
194
195 return (1);
196 }
197