inet_addr.c revision 1.7
1/* $OpenBSD: inet_addr.c,v 1.7 2003/06/02 20:18:35 millert 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 1.7 2003/06/02 20:18:35 millert 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(cp) 75 register const char *cp; 76{ 77 struct in_addr val; 78 79 if (inet_aton(cp, &val)) 80 return (val.s_addr); 81 return (INADDR_NONE); 82} 83 84/* 85 * Check whether "cp" is a valid ascii representation 86 * of an Internet address and convert to a binary address. 87 * Returns 1 if the address is valid, 0 if not. 88 * This replaces inet_addr, the return value from which 89 * cannot distinguish between failure and a local broadcast address. 90 */ 91int 92inet_aton(cp, addr) 93 register const char *cp; 94 struct in_addr *addr; 95{ 96 register in_addr_t val; 97 register int base, n; 98 register char c; 99 u_int parts[4]; 100 register u_int *pp = parts; 101 102 c = *cp; 103 for (;;) { 104 /* 105 * Collect number up to ``.''. 106 * Values are specified as for C: 107 * 0x=hex, 0=octal, isdigit=decimal. 108 */ 109 if (!isdigit(c)) 110 return (0); 111 val = 0; base = 10; 112 if (c == '0') { 113 c = *++cp; 114 if (c == 'x' || c == 'X') 115 base = 16, c = *++cp; 116 else 117 base = 8; 118 } 119 for (;;) { 120 if (isascii(c) && isdigit(c)) { 121 val = (val * base) + (c - '0'); 122 c = *++cp; 123 } else if (base == 16 && isascii(c) && isxdigit(c)) { 124 val = (val << 4) | 125 (c + 10 - (islower(c) ? 'a' : 'A')); 126 c = *++cp; 127 } else 128 break; 129 } 130 if (c == '.') { 131 /* 132 * Internet format: 133 * a.b.c.d 134 * a.b.c (with c treated as 16 bits) 135 * a.b (with b treated as 24 bits) 136 */ 137 if (pp >= parts + 3) 138 return (0); 139 *pp++ = val; 140 c = *++cp; 141 } else 142 break; 143 } 144 /* 145 * Check for trailing characters. 146 */ 147 if (c != '\0' && (!isascii(c) || !isspace(c))) 148 return (0); 149 /* 150 * Concoct the address according to 151 * the number of parts specified. 152 */ 153 n = pp - parts + 1; 154 switch (n) { 155 156 case 0: 157 return (0); /* initial nondigit */ 158 159 case 1: /* a -- 32 bits */ 160 break; 161 162 case 2: /* a.b -- 8.24 bits */ 163 if ((val > 0xffffff) || (parts[0] > 0xff)) 164 return (0); 165 val |= parts[0] << 24; 166 break; 167 168 case 3: /* a.b.c -- 8.8.16 bits */ 169 if ((val > 0xffff) || (parts[0] > 0xff) || (parts[1] > 0xff)) 170 return (0); 171 val |= (parts[0] << 24) | (parts[1] << 16); 172 break; 173 174 case 4: /* a.b.c.d -- 8.8.8.8 bits */ 175 if ((val > 0xff) || (parts[0] > 0xff) || (parts[1] > 0xff) || (parts[2] > 0xff)) 176 return (0); 177 val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8); 178 break; 179 } 180 if (addr) 181 addr->s_addr = htonl(val); 182 return (1); 183} 184