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Diffstat (limited to 'missing/inet_ntop.c')
| -rw-r--r-- | missing/inet_ntop.c | 219 |
1 files changed, 219 insertions, 0 deletions
diff --git a/missing/inet_ntop.c b/missing/inet_ntop.c new file mode 100644 index 0000000..d17d592 --- /dev/null +++ b/missing/inet_ntop.c @@ -0,0 +1,219 @@ +/* + * 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; + } +} |