1 /* 2 * Copyright 2010, Haiku, Inc. All Rights Reserved. 3 * Distributed under the terms of the MIT License. 4 */ 5 6 /* 7 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC") 8 * Copyright (c) 1996-1999 by Internet Software Consortium. 9 * 10 * Permission to use, copy, modify, and distribute this software for any 11 * purpose with or without fee is hereby granted, provided that the above 12 * copyright notice and this permission notice appear in all copies. 13 * 14 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES 15 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 16 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR 17 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 18 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 19 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT 20 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 21 */ 22 23 24 #include <net_datalink.h> 25 26 #include <ByteOrder.h> 27 #include <KernelExport.h> 28 #include <NetUtilities.h> 29 30 #include <memory.h> 31 #include <netinet6/in6.h> 32 #include <stdio.h> 33 #include <stdlib.h> 34 #include <string.h> 35 36 #include "ipv6_utils.h" 37 38 39 #define NS_IN6ADDRSZ 16 40 #define NS_INT16SZ 2 41 42 #define SPRINTF(x) ((size_t)sprintf x) 43 44 45 /*! Convert IPv6 binary address into presentation (printable) format. 46 Author: Paul Vixie, 1996. 47 \return pointer to dst string if address as been printed 48 \return NULL if the buffer is too short 49 */ 50 const char * 51 ip6_sprintf(const in6_addr *srcaddr, char *dst, size_t size) 52 { 53 /* 54 * Note that int32_t and int16_t need only be "at least" large enough 55 * to contain a value of the specified size. On some systems, like 56 * Crays, there is no such thing as an integer variable with 16 bits. 57 * Keep this in mind if you think this function should have been coded 58 * to use pointer overlays. All the world's not a VAX. 59 */ 60 char tmp[INET6_ADDRSTRLEN], *tp; 61 struct { int base, len; } best, cur; 62 uint16 words[NS_IN6ADDRSZ / NS_INT16SZ]; 63 int i; 64 const uint8 *src = srcaddr->s6_addr; 65 66 /* 67 * Preprocess: 68 * Copy the input (bytewise) array into a wordwise array. 69 * Find the longest run of 0x00's in src[] for :: shorthanding. 70 */ 71 memset(words, '\0', sizeof words); 72 for (i = 0; i < NS_IN6ADDRSZ; i++) 73 words[i / 2] |= (src[i] << ((1 - (i % 2)) << 3)); 74 best.base = -1; 75 best.len = 0; 76 cur.base = -1; 77 cur.len = 0; 78 for (i = 0; i < (NS_IN6ADDRSZ / NS_INT16SZ); i++) { 79 if (words[i] == 0) { 80 if (cur.base == -1) 81 cur.base = i, cur.len = 1; 82 else 83 cur.len++; 84 } else { 85 if (cur.base != -1) { 86 if (best.base == -1 || cur.len > best.len) 87 best = cur; 88 cur.base = -1; 89 } 90 } 91 } 92 if (cur.base != -1) { 93 if (best.base == -1 || cur.len > best.len) 94 best = cur; 95 } 96 if (best.base != -1 && best.len < 2) 97 best.base = -1; 98 99 /* 100 * Format the result. 101 */ 102 tp = tmp; 103 for (i = 0; i < (NS_IN6ADDRSZ / NS_INT16SZ); i++) { 104 /* Are we inside the best run of 0x00's? */ 105 if (best.base != -1 && i >= best.base && 106 i < (best.base + best.len)) { 107 if (i == best.base) 108 *tp++ = ':'; 109 continue; 110 } 111 /* Are we following an initial run of 0x00s or any real hex? */ 112 if (i != 0) 113 *tp++ = ':'; 114 /* Is this address an encapsulated IPv4? */ 115 #if 0 116 if (i == 6 && best.base == 0 && (best.len == 6 || 117 (best.len == 7 && words[7] != 0x0001) || 118 (best.len == 5 && words[5] == 0xffff))) { 119 if (!inet_ntop4(src+12, tp, sizeof tmp - (tp - tmp))) 120 return (NULL); 121 tp += strlen(tp); 122 break; 123 } 124 #endif 125 tp += SPRINTF((tp, "%x", words[i])); 126 } 127 /* Was it a trailing run of 0x00's? */ 128 if (best.base != -1 && (best.base + best.len) == 129 (NS_IN6ADDRSZ / NS_INT16SZ)) 130 *tp++ = ':'; 131 *tp++ = '\0'; 132 133 /* 134 * Check for overflow, copy, and we're done. 135 */ 136 if ((size_t)(tp - tmp) > size) 137 return NULL; 138 139 strcpy(dst, tmp); 140 return dst; 141 } 142