diff options
Diffstat (limited to 'contrib/tcpdump/missing/inet_ntop.c')
| -rw-r--r-- | contrib/tcpdump/missing/inet_ntop.c | 123 |
1 files changed, 119 insertions, 4 deletions
diff --git a/contrib/tcpdump/missing/inet_ntop.c b/contrib/tcpdump/missing/inet_ntop.c index 175face..8bbbad6 100644 --- a/contrib/tcpdump/missing/inet_ntop.c +++ b/contrib/tcpdump/missing/inet_ntop.c @@ -36,11 +36,11 @@ * SUCH DAMAGE. */ -/* $Id: inet_ntop.c,v 1.5.2.2 2003/11/16 08:52:01 guy Exp $ */ +/* $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 1.5.2.2 2003/11/16 08:52:01 guy Exp $"; + "@(#) $Header: /tcpdump/master/tcpdump/missing/inet_ntop.c,v 1.8 2005/02/09 02:25:46 guy Exp $"; #endif #include <tcpdump-stdinc.h> @@ -52,8 +52,12 @@ static const char rcsid[] _U_ = * */ -#ifndef INET_ADDRSTRLEN -#define INET_ADDRSTRLEN 16 +#ifndef IN6ADDRSZ +#define IN6ADDRSZ 16 /* IPv6 T_AAAA */ +#endif + +#ifndef INT16SZ +#define INT16SZ 2 /* word size */ #endif static const char * @@ -91,12 +95,123 @@ inet_ntop_v4 (const void *src, char *dst, size_t size) 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; |
