inet_addr.c revision 1.4
1/* $OpenBSD: inet_addr.c,v 1.4 1997/03/13 19:07:29 downsj 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. All advertising materials mentioning features or use of this software 18 * must display the following acknowledgement: 19 * This product includes software developed by the University of 20 * California, Berkeley and its contributors. 21 * 4. Neither the name of the University nor the names of its contributors 22 * may be used to endorse or promote products derived from this software 23 * without specific prior written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 35 * SUCH DAMAGE. 36 * - 37 * Portions Copyright (c) 1993 by Digital Equipment Corporation. 38 * 39 * Permission to use, copy, modify, and distribute this software for any 40 * purpose with or without fee is hereby granted, provided that the above 41 * copyright notice and this permission notice appear in all copies, and that 42 * the name of Digital Equipment Corporation not be used in advertising or 43 * publicity pertaining to distribution of the document or software without 44 * specific, written prior permission. 45 * 46 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL 47 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES 48 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT 49 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL 50 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR 51 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS 52 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS 53 * SOFTWARE. 54 * - 55 * --Copyright-- 56 */ 57 58#if defined(LIBC_SCCS) && !defined(lint) 59#if 0 60static char sccsid[] = "@(#)inet_addr.c 8.1 (Berkeley) 6/17/93"; 61static char rcsid[] = "$From: inet_addr.c,v 8.5 1996/08/05 08:31:35 vixie Exp $"; 62#else 63static char rcsid[] = "$OpenBSD: inet_addr.c,v 1.4 1997/03/13 19:07:29 downsj Exp $"; 64#endif 65#endif /* LIBC_SCCS and not lint */ 66 67#include <sys/types.h> 68#include <sys/param.h> 69#include <netinet/in.h> 70#include <arpa/inet.h> 71#include <ctype.h> 72 73/* 74 * Ascii internet address interpretation routine. 75 * The value returned is in network order. 76 */ 77u_long 78inet_addr(cp) 79 register const char *cp; 80{ 81 struct in_addr val; 82 83 if (inet_aton(cp, &val)) 84 return (val.s_addr); 85 return (INADDR_NONE); 86} 87 88/* 89 * Check whether "cp" is a valid ascii representation 90 * of an Internet address and convert to a binary address. 91 * Returns 1 if the address is valid, 0 if not. 92 * This replaces inet_addr, the return value from which 93 * cannot distinguish between failure and a local broadcast address. 94 */ 95int 96inet_aton(cp, addr) 97 register const char *cp; 98 struct in_addr *addr; 99{ 100 register u_long val; 101 register int base, n; 102 register char c; 103 u_int parts[4]; 104 register u_int *pp = parts; 105 106 c = *cp; 107 for (;;) { 108 /* 109 * Collect number up to ``.''. 110 * Values are specified as for C: 111 * 0x=hex, 0=octal, isdigit=decimal. 112 */ 113 if (!isdigit(c)) 114 return (0); 115 val = 0; base = 10; 116 if (c == '0') { 117 c = *++cp; 118 if (c == 'x' || c == 'X') 119 base = 16, c = *++cp; 120 else 121 base = 8; 122 } 123 for (;;) { 124 if (isascii(c) && isdigit(c)) { 125 val = (val * base) + (c - '0'); 126 c = *++cp; 127 } else if (base == 16 && isascii(c) && isxdigit(c)) { 128 val = (val << 4) | 129 (c + 10 - (islower(c) ? 'a' : 'A')); 130 c = *++cp; 131 } else 132 break; 133 } 134 if (c == '.') { 135 /* 136 * Internet format: 137 * a.b.c.d 138 * a.b.c (with c treated as 16 bits) 139 * a.b (with b treated as 24 bits) 140 */ 141 if (pp >= parts + 3) 142 return (0); 143 *pp++ = val; 144 c = *++cp; 145 } else 146 break; 147 } 148 /* 149 * Check for trailing characters. 150 */ 151 if (c != '\0' && (!isascii(c) || !isspace(c))) 152 return (0); 153 /* 154 * Concoct the address according to 155 * the number of parts specified. 156 */ 157 n = pp - parts + 1; 158 switch (n) { 159 160 case 0: 161 return (0); /* initial nondigit */ 162 163 case 1: /* a -- 32 bits */ 164 break; 165 166 case 2: /* a.b -- 8.24 bits */ 167 if (val > 0xffffff) 168 return (0); 169 val |= parts[0] << 24; 170 break; 171 172 case 3: /* a.b.c -- 8.8.16 bits */ 173 if (val > 0xffff) 174 return (0); 175 val |= (parts[0] << 24) | (parts[1] << 16); 176 break; 177 178 case 4: /* a.b.c.d -- 8.8.8.8 bits */ 179 if (val > 0xff) 180 return (0); 181 val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8); 182 break; 183 } 184 if (addr) 185 addr->s_addr = htonl(val); 186 return (1); 187} 188