ISC DHCP  4.3.0
A reference DHCPv4 and DHCPv6 implementation
inet_addr.c
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1 /* $NetBSD: inet_addr.c,v 1.6 1996/02/02 15:22:23 mrg Exp $ */
2 
3 /*
4  * Copyright (c) 1983, 1990, 1993
5  * The Regents of the University of California. All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  * notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  * notice, this list of conditions and the following disclaimer in the
14  * documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  * may be used to endorse or promote products derived from this software
17  * without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #if defined(LIBC_SCCS) && !defined(lint)
33 #if 0
34 static char sccsid[] = "@(#)inet_addr.c 8.1 (Berkeley) 6/17/93";
35 #else
36 static char rcsid[] = "$NetBSD: inet_addr.c,v 1.6 1996/02/02 15:22:23 mrg Exp $";
37 #endif
38 #endif /* LIBC_SCCS and not lint */
39 
40 #include "dhcpd.h"
41 
42 #include "omapip/omapip_p.h"
43 
44 #ifdef NEED_INET_ATON
45 /*
46  * Check whether "cp" is a valid ascii representation
47  * of an Internet address and convert to a binary address.
48  * Returns 1 if the address is valid, 0 if not.
49  * This replaces inet_addr, the return value from which
50  * cannot distinguish between failure and a local broadcast address.
51  */
52 int
53 inet_aton(cp, addr)
54  const char *cp;
55  struct in_addr *addr;
56 {
57  register u_long val;
58  register int base, n;
59  register char c;
60  u_int parts[4];
61  register u_int *pp = parts;
62 
63  for (;;) {
64  /*
65  * Collect number up to ``.''.
66  * Values are specified as for C:
67  * 0x=hex, 0=octal, other=decimal.
68  */
69  val = 0; base = 10;
70  if (*cp == '0') {
71  if (*++cp == 'x' || *cp == 'X')
72  base = 16, cp++;
73  else
74  base = 8;
75  }
76  while ((c = *cp) != '\0') {
77  if (isascii(c) && isdigit((int)c)) {
78  val = (val * base) + (c - '0');
79  cp++;
80  continue;
81  }
82  if (base == 16 && isascii(c) && isxdigit((int)c)) {
83  val = (val << 4) +
84  (c + 10 - (islower((int)c) ? 'a' : 'A'));
85  cp++;
86  continue;
87  }
88  break;
89  }
90  if (*cp == '.') {
91  /*
92  * Internet format:
93  * a.b.c.d
94  * a.b.c (with c treated as 16-bits)
95  * a.b (with b treated as 24 bits)
96  */
97  if (pp >= parts + 3 || val > 0xff)
98  return (0);
99  *pp++ = val, cp++;
100  } else
101  break;
102  }
103  /*
104  * Check for trailing characters.
105  */
106  if (*cp && (!isascii(*cp) || !isspace((int)*cp)))
107  return (0);
108  /*
109  * Concoct the address according to
110  * the number of parts specified.
111  */
112  n = pp - parts + 1;
113  switch (n) {
114 
115  case 0:
116  return (0); /* initial nondigit */
117 
118  case 1: /* a -- 32 bits */
119  break;
120 
121  case 2: /* a.b -- 8.24 bits */
122  if (val > 0xffffff)
123  return (0);
124  val |= parts[0] << 24;
125  break;
126 
127  case 3: /* a.b.c -- 8.8.16 bits */
128  if (val > 0xffff)
129  return (0);
130  val |= (parts[0] << 24) | (parts[1] << 16);
131  break;
132 
133  case 4: /* a.b.c.d -- 8.8.8.8 bits */
134  if (val > 0xff)
135  return (0);
136  val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
137  break;
138  }
139  if (addr)
140  addr->s_addr = htonl(val);
141  return (1);
142 }
143 #endif