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 #include "curl_printf.h" 36 37 #include "inet_ntop.h" 38 39 #define IN6ADDRSZ 16 40 #define INADDRSZ 4 41 #define INT16SZ 2 42 43 /* 44 * Format an IPv4 address, more or less like inet_ntoa(). 45 * 46 * Returns `dst' (as a const) 47 * Note: 48 * - uses no statics 49 * - takes a unsigned char* not an in_addr as input 50 */ 51 static char *inet_ntop4 (const unsigned char *src, char *dst, size_t size) 52 { 53 char tmp[sizeof "255.255.255.255"]; 54 size_t len; 55 56 DEBUGASSERT(size >= 16); 57 58 tmp[0] = '\0'; 59 (void)snprintf(tmp, sizeof(tmp), "%d.%d.%d.%d", 60 ((int)((unsigned char)src[0])) & 0xff, 61 ((int)((unsigned char)src[1])) & 0xff, 62 ((int)((unsigned char)src[2])) & 0xff, 63 ((int)((unsigned char)src[3])) & 0xff); 64 65 len = strlen(tmp); 66 if(len == 0 || len >= size) { 67 SET_ERRNO(ENOSPC); 68 return (NULL); 69 } 70 strcpy(dst, tmp); 71 return dst; 72 } 73 74 #ifdef ENABLE_IPV6 75 /* 76 * Convert IPv6 binary address into presentation (printable) format. 77 */ 78 static char *inet_ntop6 (const unsigned char *src, char *dst, size_t size) 79 { 80 /* 81 * Note that int32_t and int16_t need only be "at least" large enough 82 * to contain a value of the specified size. On some systems, like 83 * Crays, there is no such thing as an integer variable with 16 bits. 84 * Keep this in mind if you think this function should have been coded 85 * to use pointer overlays. All the world's not a VAX. 86 */ 87 char tmp[sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255")]; 88 char *tp; 89 struct { 90 long base; 91 long len; 92 } best, cur; 93 unsigned long words[IN6ADDRSZ / INT16SZ]; 94 int i; 95 96 /* Preprocess: 97 * Copy the input (bytewise) array into a wordwise array. 98 * Find the longest run of 0x00's in src[] for :: shorthanding. 99 */ 100 memset(words, '\0', sizeof(words)); 101 for(i = 0; i < IN6ADDRSZ; i++) 102 words[i/2] |= (src[i] << ((1 - (i % 2)) << 3)); 103 104 best.base = -1; 105 cur.base = -1; 106 best.len = 0; 107 cur.len = 0; 108 109 for(i = 0; i < (IN6ADDRSZ / INT16SZ); i++) { 110 if(words[i] == 0) { 111 if(cur.base == -1) 112 cur.base = i, cur.len = 1; 113 else 114 cur.len++; 115 } 116 else if(cur.base != -1) { 117 if(best.base == -1 || cur.len > best.len) 118 best = cur; 119 cur.base = -1; 120 } 121 } 122 if((cur.base != -1) && (best.base == -1 || cur.len > best.len)) 123 best = cur; 124 if(best.base != -1 && best.len < 2) 125 best.base = -1; 126 /* Format the result. */ 127 tp = tmp; 128 for(i = 0; i < (IN6ADDRSZ / INT16SZ); i++) { 129 /* Are we inside the best run of 0x00's? */ 130 if(best.base != -1 && i >= best.base && i < (best.base + best.len)) { 131 if(i == best.base) 132 *tp++ = ':'; 133 continue; 134 } 135 136 /* Are we following an initial run of 0x00s or any real hex? 137 */ 138 if(i != 0) 139 *tp++ = ':'; 140 141 /* Is this address an encapsulated IPv4? 142 */ 143 if(i == 6 && best.base == 0 && 144 (best.len == 6 || (best.len == 5 && words[5] == 0xffff))) { 145 if(!inet_ntop4(src+12, tp, sizeof(tmp) - (tp - tmp))) { 146 SET_ERRNO(ENOSPC); 147 return (NULL); 148 } 149 tp += strlen(tp); 150 break; 151 } 152 tp += snprintf(tp, 5, "%lx", words[i]); 153 } 154 155 /* Was it a trailing run of 0x00's? 156 */ 157 if(best.base != -1 && (best.base + best.len) == (IN6ADDRSZ / INT16SZ)) 158 *tp++ = ':'; 159 *tp++ = '\0'; 160 161 /* Check for overflow, copy, and we're done. 162 */ 163 if((size_t)(tp - tmp) > size) { 164 SET_ERRNO(ENOSPC); 165 return (NULL); 166 } 167 strcpy(dst, tmp); 168 return dst; 169 } 170 #endif /* ENABLE_IPV6 */ 171 172 /* 173 * Convert a network format address to presentation format. 174 * 175 * Returns pointer to presentation format address (`buf'). 176 * Returns NULL on error and errno set with the specific 177 * error, EAFNOSUPPORT or ENOSPC. 178 * 179 * On Windows we store the error in the thread errno, not 180 * in the winsock error code. This is to avoid losing the 181 * actual last winsock error. So use macro ERRNO to fetch the 182 * errno this function sets when returning NULL, not SOCKERRNO. 183 */ 184 char *Curl_inet_ntop(int af, const void *src, char *buf, size_t size) 185 { 186 switch (af) { 187 case AF_INET: 188 return inet_ntop4((const unsigned char*)src, buf, size); 189 #ifdef ENABLE_IPV6 190 case AF_INET6: 191 return inet_ntop6((const unsigned char*)src, buf, size); 192 #endif 193 default: 194 SET_ERRNO(EAFNOSUPPORT); 195 return NULL; 196 } 197 } 198 #endif /* HAVE_INET_NTOP */ 199
