inet_addr.c revision 1.8
1/* $OpenBSD: inet_addr.c,v 1.8 2005/03/25 13:24:12 otto 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#if defined(LIBC_SCCS) && !defined(lint) 55#if 0 56static char sccsid[] = "@(#)inet_addr.c 8.1 (Berkeley) 6/17/93"; 57static char rcsid[] = "$From: inet_addr.c,v 8.5 1996/08/05 08:31:35 vixie Exp $"; 58#else 59static char rcsid[] = "$OpenBSD: inet_addr.c,v 1.8 2005/03/25 13:24:12 otto Exp $"; 60#endif 61#endif /* LIBC_SCCS and not lint */ 62 63#include <sys/types.h> 64#include <sys/param.h> 65#include <netinet/in.h> 66#include <arpa/inet.h> 67#include <ctype.h> 68 69/* 70 * Ascii internet address interpretation routine. 71 * The value returned is in network order. 72 */ 73in_addr_t 74inet_addr(const char *cp) 75{ 76 struct in_addr val; 77 78 if (inet_aton(cp, &val)) 79 return (val.s_addr); 80 return (INADDR_NONE); 81} 82 83/* 84 * Check whether "cp" is a valid ascii representation 85 * of an Internet address and convert to a binary address. 86 * Returns 1 if the address is valid, 0 if not. 87 * This replaces inet_addr, the return value from which 88 * cannot distinguish between failure and a local broadcast address. 89 */ 90int 91inet_aton(const char *cp, struct in_addr *addr) 92{ 93 in_addr_t val; 94 int base, n; 95 char c; 96 u_int parts[4]; 97 u_int *pp = parts; 98 99 c = *cp; 100 for (;;) { 101 /* 102 * Collect number up to ``.''. 103 * Values are specified as for C: 104 * 0x=hex, 0=octal, isdigit=decimal. 105 */ 106 if (!isdigit(c)) 107 return (0); 108 val = 0; base = 10; 109 if (c == '0') { 110 c = *++cp; 111 if (c == 'x' || c == 'X') 112 base = 16, c = *++cp; 113 else 114 base = 8; 115 } 116 for (;;) { 117 if (isascii(c) && isdigit(c)) { 118 val = (val * base) + (c - '0'); 119 c = *++cp; 120 } else if (base == 16 && isascii(c) && isxdigit(c)) { 121 val = (val << 4) | 122 (c + 10 - (islower(c) ? 'a' : 'A')); 123 c = *++cp; 124 } else 125 break; 126 } 127 if (c == '.') { 128 /* 129 * Internet format: 130 * a.b.c.d 131 * a.b.c (with c treated as 16 bits) 132 * a.b (with b treated as 24 bits) 133 */ 134 if (pp >= parts + 3) 135 return (0); 136 *pp++ = val; 137 c = *++cp; 138 } else 139 break; 140 } 141 /* 142 * Check for trailing characters. 143 */ 144 if (c != '\0' && (!isascii(c) || !isspace(c))) 145 return (0); 146 /* 147 * Concoct the address according to 148 * the number of parts specified. 149 */ 150 n = pp - parts + 1; 151 switch (n) { 152 153 case 0: 154 return (0); /* initial nondigit */ 155 156 case 1: /* a -- 32 bits */ 157 break; 158 159 case 2: /* a.b -- 8.24 bits */ 160 if ((val > 0xffffff) || (parts[0] > 0xff)) 161 return (0); 162 val |= parts[0] << 24; 163 break; 164 165 case 3: /* a.b.c -- 8.8.16 bits */ 166 if ((val > 0xffff) || (parts[0] > 0xff) || (parts[1] > 0xff)) 167 return (0); 168 val |= (parts[0] << 24) | (parts[1] << 16); 169 break; 170 171 case 4: /* a.b.c.d -- 8.8.8.8 bits */ 172 if ((val > 0xff) || (parts[0] > 0xff) || (parts[1] > 0xff) || (parts[2] > 0xff)) 173 return (0); 174 val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8); 175 break; 176 } 177 if (addr) 178 addr->s_addr = htonl(val); 179 return (1); 180} 181