inet_addr.c revision 1.11
1/* $OpenBSD: inet_addr.c,v 1.11 2015/01/16 16:48:51 deraadt 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#include <sys/types.h> 55#include <netinet/in.h> 56#include <arpa/inet.h> 57#include <ctype.h> 58 59/* 60 * Ascii internet address interpretation routine. 61 * The value returned is in network order. 62 */ 63in_addr_t 64inet_addr(const char *cp) 65{ 66 struct in_addr val; 67 68 if (inet_aton(cp, &val)) 69 return (val.s_addr); 70 return (INADDR_NONE); 71} 72 73/* 74 * Check whether "cp" is a valid ascii representation 75 * of an Internet address and convert to a binary address. 76 * Returns 1 if the address is valid, 0 if not. 77 * This replaces inet_addr, the return value from which 78 * cannot distinguish between failure and a local broadcast address. 79 */ 80int 81inet_aton(const char *cp, struct in_addr *addr) 82{ 83 in_addr_t val; 84 int base, n; 85 char c; 86 u_int parts[4]; 87 u_int *pp = parts; 88 89 c = *cp; 90 for (;;) { 91 /* 92 * Collect number up to ``.''. 93 * Values are specified as for C: 94 * 0x=hex, 0=octal, isdigit=decimal. 95 */ 96 if (!isdigit((unsigned char)c)) 97 return (0); 98 val = 0; base = 10; 99 if (c == '0') { 100 c = *++cp; 101 if (c == 'x' || c == 'X') 102 base = 16, c = *++cp; 103 else 104 base = 8; 105 } 106 for (;;) { 107 if (isascii((unsigned char)c) && 108 isdigit((unsigned char)c)) { 109 val = (val * base) + (c - '0'); 110 c = *++cp; 111 } else if (base == 16 && 112 isascii((unsigned char)c) && 113 isxdigit((unsigned char)c)) { 114 val = (val << 4) | 115 (c + 10 - (islower((unsigned char)c) ? 'a' : 'A')); 116 c = *++cp; 117 } else 118 break; 119 } 120 if (c == '.') { 121 /* 122 * Internet format: 123 * a.b.c.d 124 * a.b.c (with c treated as 16 bits) 125 * a.b (with b treated as 24 bits) 126 */ 127 if (pp >= parts + 3) 128 return (0); 129 *pp++ = val; 130 c = *++cp; 131 } else 132 break; 133 } 134 /* 135 * Check for trailing characters. 136 */ 137 if (c != '\0' && 138 (!isascii((unsigned char)c) || !isspace((unsigned char)c))) 139 return (0); 140 /* 141 * Concoct the address according to 142 * the number of parts specified. 143 */ 144 n = pp - parts + 1; 145 switch (n) { 146 147 case 0: 148 return (0); /* initial nondigit */ 149 150 case 1: /* a -- 32 bits */ 151 break; 152 153 case 2: /* a.b -- 8.24 bits */ 154 if ((val > 0xffffff) || (parts[0] > 0xff)) 155 return (0); 156 val |= parts[0] << 24; 157 break; 158 159 case 3: /* a.b.c -- 8.8.16 bits */ 160 if ((val > 0xffff) || (parts[0] > 0xff) || (parts[1] > 0xff)) 161 return (0); 162 val |= (parts[0] << 24) | (parts[1] << 16); 163 break; 164 165 case 4: /* a.b.c.d -- 8.8.8.8 bits */ 166 if ((val > 0xff) || (parts[0] > 0xff) || (parts[1] > 0xff) || (parts[2] > 0xff)) 167 return (0); 168 val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8); 169 break; 170 } 171 if (addr) 172 addr->s_addr = htonl(val); 173 return (1); 174} 175