| /* |
| * Copyright (c) 1999 Kungliga Tekniska Högskolan |
| * (Royal Institute of Technology, Stockholm, Sweden). |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * |
| * 3. All advertising materials mentioning features or use of this software |
| * must display the following acknowledgement: |
| * This product includes software developed by the Kungliga Tekniska |
| * Högskolan and its contributors. |
| * |
| * 4. Neither the name of the Institute nor the names of its contributors |
| * may be used to endorse or promote products derived from this software |
| * without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND |
| * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE |
| * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| * SUCH DAMAGE. |
| */ |
| |
| /* $Id: inet_ntop.c,v 1.8 2005-02-09 02:25:46 guy Exp $ */ |
| |
| #ifndef lint |
| static const char rcsid[] _U_ = |
| "@(#) $Header: /tcpdump/master/tcpdump/missing/inet_ntop.c,v 1.8 2005-02-09 02:25:46 guy Exp $"; |
| #endif |
| |
| #include <tcpdump-stdinc.h> |
| |
| #include <stdio.h> |
| #include <errno.h> |
| |
| /* |
| * |
| */ |
| |
| #ifndef IN6ADDRSZ |
| #define IN6ADDRSZ 16 /* IPv6 T_AAAA */ |
| #endif |
| |
| #ifndef INT16SZ |
| #define INT16SZ 2 /* word size */ |
| #endif |
| |
| static const char * |
| inet_ntop_v4 (const void *src, char *dst, size_t size) |
| { |
| const char digits[] = "0123456789"; |
| int i; |
| struct in_addr *addr = (struct in_addr *)src; |
| u_long a = ntohl(addr->s_addr); |
| const char *orig_dst = dst; |
| |
| if (size < INET_ADDRSTRLEN) { |
| errno = ENOSPC; |
| return NULL; |
| } |
| for (i = 0; i < 4; ++i) { |
| int n = (a >> (24 - i * 8)) & 0xFF; |
| int non_zerop = 0; |
| |
| if (non_zerop || n / 100 > 0) { |
| *dst++ = digits[n / 100]; |
| n %= 100; |
| non_zerop = 1; |
| } |
| if (non_zerop || n / 10 > 0) { |
| *dst++ = digits[n / 10]; |
| n %= 10; |
| non_zerop = 1; |
| } |
| *dst++ = digits[n]; |
| if (i != 3) |
| *dst++ = '.'; |
| } |
| *dst++ = '\0'; |
| return orig_dst; |
| } |
| |
| #ifdef INET6 |
| /* |
| * Convert IPv6 binary address into presentation (printable) format. |
| */ |
| static const char * |
| inet_ntop_v6 (const u_char *src, char *dst, size_t size) |
| { |
| /* |
| * Note that int32_t and int16_t need only be "at least" large enough |
| * to contain a value of the specified size. On some systems, like |
| * Crays, there is no such thing as an integer variable with 16 bits. |
| * Keep this in mind if you think this function should have been coded |
| * to use pointer overlays. All the world's not a VAX. |
| */ |
| char tmp [INET6_ADDRSTRLEN+1]; |
| char *tp; |
| struct { |
| long base; |
| long len; |
| } best, cur; |
| u_long words [IN6ADDRSZ / INT16SZ]; |
| int i; |
| |
| /* Preprocess: |
| * Copy the input (bytewise) array into a wordwise array. |
| * Find the longest run of 0x00's in src[] for :: shorthanding. |
| */ |
| memset (words, 0, sizeof(words)); |
| for (i = 0; i < IN6ADDRSZ; i++) |
| words[i/2] |= (src[i] << ((1 - (i % 2)) << 3)); |
| |
| best.base = -1; |
| cur.base = -1; |
| for (i = 0; i < (IN6ADDRSZ / INT16SZ); i++) |
| { |
| if (words[i] == 0) |
| { |
| if (cur.base == -1) |
| cur.base = i, cur.len = 1; |
| else cur.len++; |
| } |
| else if (cur.base != -1) |
| { |
| if (best.base == -1 || cur.len > best.len) |
| best = cur; |
| cur.base = -1; |
| } |
| } |
| if ((cur.base != -1) && (best.base == -1 || cur.len > best.len)) |
| best = cur; |
| if (best.base != -1 && best.len < 2) |
| best.base = -1; |
| |
| /* Format the result. |
| */ |
| tp = tmp; |
| for (i = 0; i < (IN6ADDRSZ / INT16SZ); i++) |
| { |
| /* Are we inside the best run of 0x00's? |
| */ |
| if (best.base != -1 && i >= best.base && i < (best.base + best.len)) |
| { |
| if (i == best.base) |
| *tp++ = ':'; |
| continue; |
| } |
| |
| /* Are we following an initial run of 0x00s or any real hex? |
| */ |
| if (i != 0) |
| *tp++ = ':'; |
| |
| /* Is this address an encapsulated IPv4? |
| */ |
| if (i == 6 && best.base == 0 && |
| (best.len == 6 || (best.len == 5 && words[5] == 0xffff))) |
| { |
| if (!inet_ntop_v4(src+12, tp, sizeof(tmp) - (tp - tmp))) |
| { |
| errno = ENOSPC; |
| return (NULL); |
| } |
| tp += strlen(tp); |
| break; |
| } |
| tp += sprintf (tp, "%lX", words[i]); |
| } |
| |
| /* Was it a trailing run of 0x00's? |
| */ |
| if (best.base != -1 && (best.base + best.len) == (IN6ADDRSZ / INT16SZ)) |
| *tp++ = ':'; |
| *tp++ = '\0'; |
| |
| /* Check for overflow, copy, and we're done. |
| */ |
| if ((size_t)(tp - tmp) > size) |
| { |
| errno = ENOSPC; |
| return (NULL); |
| } |
| return strcpy (dst, tmp); |
| return (NULL); |
| } |
| #endif /* INET6 */ |
| |
| |
| const char * |
| inet_ntop(int af, const void *src, char *dst, size_t size) |
| { |
| switch (af) { |
| case AF_INET : |
| return inet_ntop_v4 (src, dst, size); |
| #ifdef INET6 |
| case AF_INET6: |
| return inet_ntop_v6 ((const u_char*)src, dst, size); |
| #endif |
| default : |
| errno = EAFNOSUPPORT; |
| return NULL; |
| } |
| } |