1/* 2 * Copyright (C) 1996-2001 Internet Software Consortium. 3 * 4 * Permission to use, copy, modify, and distribute this software for any 5 * purpose with or without fee is hereby granted, provided that the above 6 * copyright notice and this permission notice appear in all copies. 7 * 8 * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM 9 * DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL 10 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL 11 * INTERNET SOFTWARE CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, 12 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING 13 * FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, 14 * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION 15 * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 16 */ 17/* 18 * Original code by Paul Vixie. "curlified" by Gisle Vanem. 19 */ 20 21#include "curl_setup.h" 22 23#ifndef HAVE_INET_NTOP 24 25#ifdef HAVE_SYS_PARAM_H 26#include <sys/param.h> 27#endif 28#ifdef HAVE_NETINET_IN_H 29#include <netinet/in.h> 30#endif 31#ifdef HAVE_ARPA_INET_H 32#include <arpa/inet.h> 33#endif 34 35#define _MPRINTF_REPLACE /* use our functions only */ 36#include <curl/mprintf.h> 37 38#include "inet_ntop.h" 39 40#define IN6ADDRSZ 16 41#define INADDRSZ 4 42#define INT16SZ 2 43 44/* 45 * Format an IPv4 address, more or less like inet_ntoa(). 46 * 47 * Returns `dst' (as a const) 48 * Note: 49 * - uses no statics 50 * - takes a unsigned char* not an in_addr as input 51 */ 52static char *inet_ntop4 (const unsigned char *src, char *dst, size_t size) 53{ 54 char tmp[sizeof "255.255.255.255"]; 55 size_t len; 56 57 DEBUGASSERT(size >= 16); 58 59 tmp[0] = '\0'; 60 (void)snprintf(tmp, sizeof(tmp), "%d.%d.%d.%d", 61 ((int)((unsigned char)src[0])) & 0xff, 62 ((int)((unsigned char)src[1])) & 0xff, 63 ((int)((unsigned char)src[2])) & 0xff, 64 ((int)((unsigned char)src[3])) & 0xff); 65 66 len = strlen(tmp); 67 if(len == 0 || len >= size) { 68 SET_ERRNO(ENOSPC); 69 return (NULL); 70 } 71 strcpy(dst, tmp); 72 return dst; 73} 74 75#ifdef ENABLE_IPV6 76/* 77 * Convert IPv6 binary address into presentation (printable) format. 78 */ 79static char *inet_ntop6 (const unsigned char *src, char *dst, size_t size) 80{ 81 /* 82 * Note that int32_t and int16_t need only be "at least" large enough 83 * to contain a value of the specified size. On some systems, like 84 * Crays, there is no such thing as an integer variable with 16 bits. 85 * Keep this in mind if you think this function should have been coded 86 * to use pointer overlays. All the world's not a VAX. 87 */ 88 char tmp[sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255")]; 89 char *tp; 90 struct { 91 long base; 92 long len; 93 } best, cur; 94 unsigned long words[IN6ADDRSZ / INT16SZ]; 95 int i; 96 97 /* Preprocess: 98 * Copy the input (bytewise) array into a wordwise array. 99 * Find the longest run of 0x00's in src[] for :: shorthanding. 100 */ 101 memset(words, '\0', sizeof(words)); 102 for(i = 0; i < IN6ADDRSZ; i++) 103 words[i/2] |= (src[i] << ((1 - (i % 2)) << 3)); 104 105 best.base = -1; 106 cur.base = -1; 107 best.len = 0; 108 cur.len = 0; 109 110 for(i = 0; i < (IN6ADDRSZ / INT16SZ); i++) { 111 if(words[i] == 0) { 112 if(cur.base == -1) 113 cur.base = i, cur.len = 1; 114 else 115 cur.len++; 116 } 117 else if(cur.base != -1) { 118 if(best.base == -1 || cur.len > best.len) 119 best = cur; 120 cur.base = -1; 121 } 122 } 123 if((cur.base != -1) && (best.base == -1 || cur.len > best.len)) 124 best = cur; 125 if(best.base != -1 && best.len < 2) 126 best.base = -1; 127 /* Format the result. */ 128 tp = tmp; 129 for(i = 0; i < (IN6ADDRSZ / INT16SZ); i++) { 130 /* Are we inside the best run of 0x00's? */ 131 if(best.base != -1 && i >= best.base && i < (best.base + best.len)) { 132 if(i == best.base) 133 *tp++ = ':'; 134 continue; 135 } 136 137 /* Are we following an initial run of 0x00s or any real hex? 138 */ 139 if(i != 0) 140 *tp++ = ':'; 141 142 /* Is this address an encapsulated IPv4? 143 */ 144 if(i == 6 && best.base == 0 && 145 (best.len == 6 || (best.len == 5 && words[5] == 0xffff))) { 146 if(!inet_ntop4(src+12, tp, sizeof(tmp) - (tp - tmp))) { 147 SET_ERRNO(ENOSPC); 148 return (NULL); 149 } 150 tp += strlen(tp); 151 break; 152 } 153 tp += snprintf(tp, 5, "%lx", words[i]); 154 } 155 156 /* Was it a trailing run of 0x00's? 157 */ 158 if(best.base != -1 && (best.base + best.len) == (IN6ADDRSZ / INT16SZ)) 159 *tp++ = ':'; 160 *tp++ = '\0'; 161 162 /* Check for overflow, copy, and we're done. 163 */ 164 if((size_t)(tp - tmp) > size) { 165 SET_ERRNO(ENOSPC); 166 return (NULL); 167 } 168 strcpy(dst, tmp); 169 return dst; 170} 171#endif /* ENABLE_IPV6 */ 172 173/* 174 * Convert a network format address to presentation format. 175 * 176 * Returns pointer to presentation format address (`buf'). 177 * Returns NULL on error and errno set with the specific 178 * error, EAFNOSUPPORT or ENOSPC. 179 * 180 * On Windows we store the error in the thread errno, not 181 * in the winsock error code. This is to avoid losing the 182 * actual last winsock error. So use macro ERRNO to fetch the 183 * errno this function sets when returning NULL, not SOCKERRNO. 184 */ 185char *Curl_inet_ntop(int af, const void *src, char *buf, size_t size) 186{ 187 switch (af) { 188 case AF_INET: 189 return inet_ntop4((const unsigned char*)src, buf, size); 190#ifdef ENABLE_IPV6 191 case AF_INET6: 192 return inet_ntop6((const unsigned char*)src, buf, size); 193#endif 194 default: 195 SET_ERRNO(EAFNOSUPPORT); 196 return NULL; 197 } 198} 199#endif /* HAVE_INET_NTOP */ 200