1 /* $OpenBSD: inet_addr.c,v 1.9 2005/08/06 20:30:03 espie 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 <sys/param.h> 56 #include <netinet/in.h> 57 #include <arpa/inet.h> 58 #include <ctype.h> 59 60 /* 61 * Ascii internet address interpretation routine. 62 * The value returned is in network order. 63 */ 64 in_addr_t 65 inet_addr(const char *cp) 66 { 67 struct in_addr val; 68 69 if (inet_aton(cp, &val)) 70 return (val.s_addr); 71 return (INADDR_NONE); 72 } 73 74 /* 75 * Check whether "cp" is a valid ascii representation 76 * of an Internet address and convert to a binary address. 77 * Returns 1 if the address is valid, 0 if not. 78 * This replaces inet_addr, the return value from which 79 * cannot distinguish between failure and a local broadcast address. 80 */ 81 int 82 inet_aton(const char *cp, struct in_addr *addr) 83 { 84 in_addr_t val; 85 int base, n; 86 char c; 87 u_int parts[4]; 88 u_int *pp = parts; 89 90 c = *cp; 91 for (;;) { 92 /* 93 * Collect number up to ``.''. 94 * Values are specified as for C: 95 * 0x=hex, 0=octal, isdigit=decimal. 96 */ 97 if (!isdigit(c)) 98 return (0); 99 val = 0; base = 10; 100 if (c == '0') { 101 c = *++cp; 102 if (c == 'x' || c == 'X') 103 base = 16, c = *++cp; 104 else 105 base = 8; 106 } 107 for (;;) { 108 if (isascii(c) && isdigit(c)) { 109 val = (val * base) + (c - '0'); 110 c = *++cp; 111 } else if (base == 16 && isascii(c) && isxdigit(c)) { 112 val = (val << 4) | 113 (c + 10 - (islower(c) ? 'a' : 'A')); 114 c = *++cp; 115 } else 116 break; 117 } 118 if (c == '.') { 119 /* 120 * Internet format: 121 * a.b.c.d 122 * a.b.c (with c treated as 16 bits) 123 * a.b (with b treated as 24 bits) 124 */ 125 if (pp >= parts + 3) 126 return (0); 127 *pp++ = val; 128 c = *++cp; 129 } else 130 break; 131 } 132 /* 133 * Check for trailing characters. 134 */ 135 if (c != '\0' && (!isascii(c) || !isspace(c))) 136 return (0); 137 /* 138 * Concoct the address according to 139 * the number of parts specified. 140 */ 141 n = pp - parts + 1; 142 switch (n) { 143 144 case 0: 145 return (0); /* initial nondigit */ 146 147 case 1: /* a -- 32 bits */ 148 break; 149 150 case 2: /* a.b -- 8.24 bits */ 151 if ((val > 0xffffff) || (parts[0] > 0xff)) 152 return (0); 153 val |= parts[0] << 24; 154 break; 155 156 case 3: /* a.b.c -- 8.8.16 bits */ 157 if ((val > 0xffff) || (parts[0] > 0xff) || (parts[1] > 0xff)) 158 return (0); 159 val |= (parts[0] << 24) | (parts[1] << 16); 160 break; 161 162 case 4: /* a.b.c.d -- 8.8.8.8 bits */ 163 if ((val > 0xff) || (parts[0] > 0xff) || (parts[1] > 0xff) || (parts[2] > 0xff)) 164 return (0); 165 val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8); 166 break; 167 } 168 if (addr) 169 addr->s_addr = htonl(val); 170 return (1); 171 } 172