1238106Sdes/* From openssh 4.3p2 compat/inet_ntop.c */ 2238106Sdes/* Copyright (c) 1996 by Internet Software Consortium. 3238106Sdes * 4238106Sdes * Permission to use, copy, modify, and distribute this software for any 5238106Sdes * purpose with or without fee is hereby granted, provided that the above 6238106Sdes * copyright notice and this permission notice appear in all copies. 7238106Sdes * 8238106Sdes * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS 9238106Sdes * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES 10238106Sdes * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE 11238106Sdes * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL 12238106Sdes * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR 13238106Sdes * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS 14238106Sdes * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS 15238106Sdes * SOFTWARE. 16238106Sdes */ 17238106Sdes 18238106Sdes/* OPENBSD ORIGINAL: lib/libc/net/inet_ntop.c */ 19238106Sdes 20238106Sdes#include <config.h> 21238106Sdes 22238106Sdes#ifndef HAVE_INET_NTOP 23238106Sdes 24238106Sdes#include <sys/param.h> 25238106Sdes#include <sys/types.h> 26238106Sdes#ifdef HAVE_SYS_SOCKET_H 27238106Sdes#include <sys/socket.h> 28238106Sdes#endif 29238106Sdes#ifdef HAVE_NETINET_IN_H 30238106Sdes#include <netinet/in.h> 31238106Sdes#endif 32238106Sdes#include <string.h> 33238106Sdes#include <errno.h> 34238106Sdes#include <stdio.h> 35238106Sdes 36238106Sdes#ifndef IN6ADDRSZ 37238106Sdes#define IN6ADDRSZ 16 /* IPv6 T_AAAA */ 38238106Sdes#endif 39238106Sdes 40238106Sdes#ifndef INT16SZ 41238106Sdes#define INT16SZ 2 /* for systems without 16-bit ints */ 42238106Sdes#endif 43238106Sdes 44238106Sdes/* 45238106Sdes * WARNING: Don't even consider trying to compile this on a system where 46238106Sdes * sizeof(int) < 4. sizeof(int) > 4 is fine; all the world's not a VAX. 47238106Sdes */ 48238106Sdes 49238106Sdesstatic const char *inet_ntop4(const u_char *src, char *dst, size_t size); 50238106Sdesstatic const char *inet_ntop6(const u_char *src, char *dst, size_t size); 51238106Sdes 52238106Sdes/* char * 53238106Sdes * inet_ntop(af, src, dst, size) 54238106Sdes * convert a network format address to presentation format. 55238106Sdes * return: 56238106Sdes * pointer to presentation format address (`dst'), or NULL (see errno). 57238106Sdes * author: 58238106Sdes * Paul Vixie, 1996. 59238106Sdes */ 60238106Sdesconst char * 61238106Sdesinet_ntop(int af, const void *src, char *dst, size_t size) 62238106Sdes{ 63238106Sdes switch (af) { 64238106Sdes case AF_INET: 65238106Sdes return (inet_ntop4(src, dst, size)); 66238106Sdes case AF_INET6: 67238106Sdes return (inet_ntop6(src, dst, size)); 68238106Sdes default: 69238106Sdes#ifdef EAFNOSUPPORT 70238106Sdes errno = EAFNOSUPPORT; 71238106Sdes#else 72238106Sdes errno = ENOSYS; 73238106Sdes#endif 74238106Sdes return (NULL); 75238106Sdes } 76238106Sdes /* NOTREACHED */ 77238106Sdes} 78238106Sdes 79238106Sdes/* const char * 80238106Sdes * inet_ntop4(src, dst, size) 81238106Sdes * format an IPv4 address, more or less like inet_ntoa() 82238106Sdes * return: 83238106Sdes * `dst' (as a const) 84238106Sdes * notes: 85238106Sdes * (1) uses no statics 86238106Sdes * (2) takes a u_char* not an in_addr as input 87238106Sdes * author: 88238106Sdes * Paul Vixie, 1996. 89238106Sdes */ 90238106Sdesstatic const char * 91238106Sdesinet_ntop4(const u_char *src, char *dst, size_t size) 92238106Sdes{ 93238106Sdes static const char fmt[] = "%u.%u.%u.%u"; 94238106Sdes char tmp[sizeof "255.255.255.255"]; 95238106Sdes int l; 96238106Sdes 97238106Sdes l = snprintf(tmp, size, fmt, src[0], src[1], src[2], src[3]); 98238106Sdes if (l <= 0 || l >= (int)size) { 99238106Sdes errno = ENOSPC; 100238106Sdes return (NULL); 101238106Sdes } 102238106Sdes strlcpy(dst, tmp, size); 103238106Sdes return (dst); 104238106Sdes} 105238106Sdes 106238106Sdes/* const char * 107238106Sdes * inet_ntop6(src, dst, size) 108238106Sdes * convert IPv6 binary address into presentation (printable) format 109238106Sdes * author: 110238106Sdes * Paul Vixie, 1996. 111238106Sdes */ 112238106Sdesstatic const char * 113238106Sdesinet_ntop6(const u_char *src, char *dst, size_t size) 114238106Sdes{ 115238106Sdes /* 116238106Sdes * Note that int32_t and int16_t need only be "at least" large enough 117238106Sdes * to contain a value of the specified size. On some systems, like 118238106Sdes * Crays, there is no such thing as an integer variable with 16 bits. 119238106Sdes * Keep this in mind if you think this function should have been coded 120238106Sdes * to use pointer overlays. All the world's not a VAX. 121238106Sdes */ 122238106Sdes char tmp[sizeof "ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255"]; 123238106Sdes char *tp, *ep; 124238106Sdes struct { int base, len; } best, cur; 125238106Sdes u_int words[IN6ADDRSZ / INT16SZ]; 126238106Sdes int i; 127238106Sdes int advance; 128238106Sdes 129238106Sdes /* 130238106Sdes * Preprocess: 131238106Sdes * Copy the input (bytewise) array into a wordwise array. 132238106Sdes * Find the longest run of 0x00's in src[] for :: shorthanding. 133238106Sdes */ 134238106Sdes memset(words, '\0', sizeof words); 135238106Sdes for (i = 0; i < IN6ADDRSZ; i++) 136238106Sdes words[i / 2] |= (src[i] << ((1 - (i % 2)) << 3)); 137238106Sdes best.base = -1; 138238106Sdes best.len = 0; 139238106Sdes cur.base = -1; 140238106Sdes cur.len = 0; 141238106Sdes for (i = 0; i < (IN6ADDRSZ / INT16SZ); i++) { 142238106Sdes if (words[i] == 0) { 143238106Sdes if (cur.base == -1) 144238106Sdes cur.base = i, cur.len = 1; 145238106Sdes else 146238106Sdes cur.len++; 147238106Sdes } else { 148238106Sdes if (cur.base != -1) { 149238106Sdes if (best.base == -1 || cur.len > best.len) 150238106Sdes best = cur; 151238106Sdes cur.base = -1; 152238106Sdes } 153238106Sdes } 154238106Sdes } 155238106Sdes if (cur.base != -1) { 156238106Sdes if (best.base == -1 || cur.len > best.len) 157238106Sdes best = cur; 158238106Sdes } 159238106Sdes if (best.base != -1 && best.len < 2) 160238106Sdes best.base = -1; 161238106Sdes 162238106Sdes /* 163238106Sdes * Format the result. 164238106Sdes */ 165238106Sdes tp = tmp; 166238106Sdes ep = tmp + sizeof(tmp); 167238106Sdes for (i = 0; i < (IN6ADDRSZ / INT16SZ) && tp < ep; i++) { 168238106Sdes /* Are we inside the best run of 0x00's? */ 169238106Sdes if (best.base != -1 && i >= best.base && 170238106Sdes i < (best.base + best.len)) { 171238106Sdes if (i == best.base) { 172238106Sdes if (tp + 1 >= ep) 173238106Sdes return (NULL); 174238106Sdes *tp++ = ':'; 175238106Sdes } 176238106Sdes continue; 177238106Sdes } 178238106Sdes /* Are we following an initial run of 0x00s or any real hex? */ 179238106Sdes if (i != 0) { 180238106Sdes if (tp + 1 >= ep) 181238106Sdes return (NULL); 182238106Sdes *tp++ = ':'; 183238106Sdes } 184238106Sdes /* Is this address an encapsulated IPv4? */ 185238106Sdes if (i == 6 && best.base == 0 && 186238106Sdes (best.len == 6 || (best.len == 5 && words[5] == 0xffff))) { 187238106Sdes if (!inet_ntop4(src+12, tp, (size_t)(ep - tp))) 188238106Sdes return (NULL); 189238106Sdes tp += strlen(tp); 190238106Sdes break; 191238106Sdes } 192238106Sdes advance = snprintf(tp, ep - tp, "%x", words[i]); 193238106Sdes if (advance <= 0 || advance >= ep - tp) 194238106Sdes return (NULL); 195238106Sdes tp += advance; 196238106Sdes } 197238106Sdes /* Was it a trailing run of 0x00's? */ 198238106Sdes if (best.base != -1 && (best.base + best.len) == (IN6ADDRSZ / INT16SZ)) { 199238106Sdes if (tp + 1 >= ep) 200238106Sdes return (NULL); 201238106Sdes *tp++ = ':'; 202238106Sdes } 203238106Sdes if (tp + 1 >= ep) 204238106Sdes return (NULL); 205238106Sdes *tp++ = '\0'; 206238106Sdes 207238106Sdes /* 208238106Sdes * Check for overflow, copy, and we're done. 209238106Sdes */ 210238106Sdes if ((size_t)(tp - tmp) > size) { 211238106Sdes errno = ENOSPC; 212238106Sdes return (NULL); 213238106Sdes } 214238106Sdes strlcpy(dst, tmp, size); 215238106Sdes return (dst); 216238106Sdes} 217238106Sdes 218238106Sdes#endif /* !HAVE_INET_NTOP */ 219