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