1177633Sdfr/* 2177633Sdfr * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC") 3177633Sdfr * Copyright (c) 1996-1999 by Internet Software Consortium. 4177633Sdfr * 5177633Sdfr * Permission to use, copy, modify, and distribute this software for any 6177633Sdfr * purpose with or without fee is hereby granted, provided that the above 7177633Sdfr * copyright notice and this permission notice appear in all copies. 8177633Sdfr * 9177633Sdfr * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES 10177633Sdfr * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 11177633Sdfr * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR 12177633Sdfr * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 13177633Sdfr * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 14177633Sdfr * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT 15177633Sdfr * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 16177633Sdfr */ 17177633Sdfr 18177633Sdfr#if defined(LIBC_SCCS) && !defined(lint) 19177633Sdfrstatic const char rcsid[] = "$Id: inet_ntop.c,v 1.3.18.2 2005/11/03 23:02:22 marka Exp $"; 20177633Sdfr#endif /* LIBC_SCCS and not lint */ 21177633Sdfr#include <sys/cdefs.h> 22177633Sdfr__FBSDID("$FreeBSD$"); 23177633Sdfr 24177633Sdfr#include <sys/param.h> 25177633Sdfr#include <sys/socket.h> 26177633Sdfr#include <sys/systm.h> 27177633Sdfr 28213103Sattilio#include <netinet/in.h> 29177633Sdfr 30177633Sdfr/*% 31177633Sdfr * WARNING: Don't even consider trying to compile this on a system where 32177633Sdfr * sizeof(int) < 4. sizeof(int) > 4 is fine; all the world's not a VAX. 33177633Sdfr */ 34177633Sdfr 35213103Sattiliostatic char *inet_ntop4(const u_char *src, char *dst, socklen_t size); 36213103Sattiliostatic char *inet_ntop6(const u_char *src, char *dst, socklen_t size); 37177633Sdfr 38177633Sdfr/* char * 39177633Sdfr * inet_ntop(af, src, dst, size) 40177633Sdfr * convert a network format address to presentation format. 41177633Sdfr * return: 42177633Sdfr * pointer to presentation format address (`dst'), or NULL (see errno). 43177633Sdfr * author: 44177633Sdfr * Paul Vixie, 1996. 45177633Sdfr */ 46213103Sattiliochar * 47213103Sattilioinet_ntop(int af, const void *src, char *dst, socklen_t size) 48177633Sdfr{ 49177633Sdfr switch (af) { 50177633Sdfr case AF_INET: 51177633Sdfr return (inet_ntop4(src, dst, size)); 52177633Sdfr case AF_INET6: 53177633Sdfr return (inet_ntop6(src, dst, size)); 54177633Sdfr default: 55177633Sdfr return (NULL); 56177633Sdfr } 57177633Sdfr /* NOTREACHED */ 58177633Sdfr} 59177633Sdfr 60177633Sdfr/* const char * 61177633Sdfr * inet_ntop4(src, dst, size) 62177633Sdfr * format an IPv4 address 63177633Sdfr * return: 64177633Sdfr * `dst' (as a const) 65177633Sdfr * notes: 66177633Sdfr * (1) uses no statics 67177633Sdfr * (2) takes a u_char* not an in_addr as input 68177633Sdfr * author: 69177633Sdfr * Paul Vixie, 1996. 70177633Sdfr */ 71213103Sattiliostatic char * 72177633Sdfrinet_ntop4(const u_char *src, char *dst, socklen_t size) 73177633Sdfr{ 74177633Sdfr static const char fmt[] = "%u.%u.%u.%u"; 75177633Sdfr char tmp[sizeof "255.255.255.255"]; 76177633Sdfr int l; 77177633Sdfr 78177633Sdfr l = snprintf(tmp, sizeof(tmp), fmt, src[0], src[1], src[2], src[3]); 79177633Sdfr if (l <= 0 || (socklen_t) l >= size) { 80177633Sdfr return (NULL); 81177633Sdfr } 82177633Sdfr strlcpy(dst, tmp, size); 83177633Sdfr return (dst); 84177633Sdfr} 85177633Sdfr 86177633Sdfr/* const char * 87177633Sdfr * inet_ntop6(src, dst, size) 88177633Sdfr * convert IPv6 binary address into presentation (printable) format 89177633Sdfr * author: 90177633Sdfr * Paul Vixie, 1996. 91177633Sdfr */ 92213103Sattiliostatic char * 93177633Sdfrinet_ntop6(const u_char *src, char *dst, socklen_t size) 94177633Sdfr{ 95177633Sdfr /* 96177633Sdfr * Note that int32_t and int16_t need only be "at least" large enough 97177633Sdfr * to contain a value of the specified size. On some systems, like 98177633Sdfr * Crays, there is no such thing as an integer variable with 16 bits. 99177633Sdfr * Keep this in mind if you think this function should have been coded 100177633Sdfr * to use pointer overlays. All the world's not a VAX. 101177633Sdfr */ 102177633Sdfr char tmp[sizeof "ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255"], *tp; 103177633Sdfr struct { int base, len; } best, cur; 104177633Sdfr#define NS_IN6ADDRSZ 16 105177633Sdfr#define NS_INT16SZ 2 106177633Sdfr u_int words[NS_IN6ADDRSZ / NS_INT16SZ]; 107177633Sdfr int i; 108177633Sdfr 109177633Sdfr /* 110177633Sdfr * Preprocess: 111177633Sdfr * Copy the input (bytewise) array into a wordwise array. 112177633Sdfr * Find the longest run of 0x00's in src[] for :: shorthanding. 113177633Sdfr */ 114177633Sdfr memset(words, '\0', sizeof words); 115177633Sdfr for (i = 0; i < NS_IN6ADDRSZ; i++) 116177633Sdfr words[i / 2] |= (src[i] << ((1 - (i % 2)) << 3)); 117177633Sdfr best.base = -1; 118177633Sdfr best.len = 0; 119177633Sdfr cur.base = -1; 120177633Sdfr cur.len = 0; 121177633Sdfr for (i = 0; i < (NS_IN6ADDRSZ / NS_INT16SZ); i++) { 122177633Sdfr if (words[i] == 0) { 123177633Sdfr if (cur.base == -1) 124177633Sdfr cur.base = i, cur.len = 1; 125177633Sdfr else 126177633Sdfr cur.len++; 127177633Sdfr } else { 128177633Sdfr if (cur.base != -1) { 129177633Sdfr if (best.base == -1 || cur.len > best.len) 130177633Sdfr best = cur; 131177633Sdfr cur.base = -1; 132177633Sdfr } 133177633Sdfr } 134177633Sdfr } 135177633Sdfr if (cur.base != -1) { 136177633Sdfr if (best.base == -1 || cur.len > best.len) 137177633Sdfr best = cur; 138177633Sdfr } 139177633Sdfr if (best.base != -1 && best.len < 2) 140177633Sdfr best.base = -1; 141177633Sdfr 142177633Sdfr /* 143177633Sdfr * Format the result. 144177633Sdfr */ 145177633Sdfr tp = tmp; 146177633Sdfr for (i = 0; i < (NS_IN6ADDRSZ / NS_INT16SZ); i++) { 147177633Sdfr /* Are we inside the best run of 0x00's? */ 148177633Sdfr if (best.base != -1 && i >= best.base && 149177633Sdfr i < (best.base + best.len)) { 150177633Sdfr if (i == best.base) 151177633Sdfr *tp++ = ':'; 152177633Sdfr continue; 153177633Sdfr } 154177633Sdfr /* Are we following an initial run of 0x00s or any real hex? */ 155177633Sdfr if (i != 0) 156177633Sdfr *tp++ = ':'; 157177633Sdfr /* Is this address an encapsulated IPv4? */ 158177633Sdfr if (i == 6 && best.base == 0 && (best.len == 6 || 159177633Sdfr (best.len == 7 && words[7] != 0x0001) || 160177633Sdfr (best.len == 5 && words[5] == 0xffff))) { 161177633Sdfr if (!inet_ntop4(src+12, tp, sizeof tmp - (tp - tmp))) 162177633Sdfr return (NULL); 163177633Sdfr tp += strlen(tp); 164177633Sdfr break; 165177633Sdfr } 166177633Sdfr tp += sprintf(tp, "%x", words[i]); 167177633Sdfr } 168177633Sdfr /* Was it a trailing run of 0x00's? */ 169177633Sdfr if (best.base != -1 && (best.base + best.len) == 170177633Sdfr (NS_IN6ADDRSZ / NS_INT16SZ)) 171177633Sdfr *tp++ = ':'; 172177633Sdfr *tp++ = '\0'; 173177633Sdfr 174177633Sdfr /* 175177633Sdfr * Check for overflow, copy, and we're done. 176177633Sdfr */ 177177633Sdfr if ((socklen_t)(tp - tmp) > size) { 178177633Sdfr return (NULL); 179177633Sdfr } 180177633Sdfr strcpy(dst, tmp); 181177633Sdfr return (dst); 182177633Sdfr} 183177633Sdfr 184177633Sdfr/*! \file */ 185