/* Copyright (c) 1996 by Internet Software Consortium. * * Permission to use, copy, modify, and distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS * SOFTWARE. */ /* Modified by Fyodor (fyodor@nmap.org) for inclusion in the Nmap * Security Scanner. * * $Id$ */ #include "nbase.h" #if HAVE_SYS_TYPES_H #include #endif #if HAVE_SYS_SOCKET_H #include #endif #if HAVE_NETINET_IN_H #include #endif #if HAVE_ARPA_INET_H #include #endif #include #if HAVE_ERRNO_H #include #endif #include #ifndef IN6ADDRSZ #define IN6ADDRSZ 16 #endif #ifndef INT16SZ #define INT16SZ sizeof(u16) #endif #if !defined(EAFNOSUPPORT) && defined(WSAEAFNOSUPPORT) #define EAFNOSUPPORT WSAEAFNOSUPPORT #endif /* * WARNING: Don't even consider trying to compile this on a system where * sizeof(int) < 4. sizeof(int) > 4 is fine; all the world's not a VAX. */ static const char *inet_ntop4(const unsigned char *src, char *dst, size_t size); #if HAVE_IPV6 static const char *inet_ntop6(const unsigned char *src, char *dst, size_t size); #endif /* char * * inet_ntop(af, src, dst, size) * convert a network format address to presentation format. * return: * pointer to presentation format address (`dst'), or NULL (see errno). * author: * Paul Vixie, 1996. */ const char * inet_ntop(int af, const void *src, char *dst, size_t size) { switch (af) { case AF_INET: return (inet_ntop4((const unsigned char *) src, dst, size)); #if HAVE_IPV6 case AF_INET6: return (inet_ntop6((const unsigned char *) src, dst, size)); #endif default: #ifndef WIN32 errno = EAFNOSUPPORT; #endif return (NULL); } /* NOTREACHED */ } /* const char * * inet_ntop4(src, dst, size) * format an IPv4 address, more or less like inet_ntoa() * return: * `dst' (as a const) * notes: * (1) uses no statics * (2) takes a u_char* not an in_addr as input * author: * Paul Vixie, 1996. */ static const char * inet_ntop4(const unsigned char *src, char *dst, size_t size) { const size_t MIN_SIZE = 16; /* space for 255.255.255.255\0 */ int n = 0; char *next = dst; if (size < MIN_SIZE) { #ifndef WIN32 errno = ENOSPC; #endif return NULL; } do { unsigned char u = *src++; if (u > 99) { *next++ = '0' + u/100; u %= 100; *next++ = '0' + u/10; u %= 10; } else if (u > 9) { *next++ = '0' + u/10; u %= 10; } *next++ = '0' + u; *next++ = '.'; n++; } while (n < 4); *--next = 0; return dst; } #if HAVE_IPV6 /* const char * * inet_ntop6(src, dst, size) * convert IPv6 binary address into presentation (printable) format * author: * Paul Vixie, 1996. */ static const char * inet_ntop6(const unsigned 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[sizeof "ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255"], *tp; struct { int base, len; } best, cur; u16 words[IN6ADDRSZ / INT16SZ]; int i; const unsigned char *next_src, *src_end; u16 *next_dest; /* * Preprocess: * Copy the input (bytewise) array into a wordwise array. * Find the longest run of 0x00's in src[] for :: shorthanding. */ next_src = src; src_end = src + IN6ADDRSZ; next_dest = words; best.base = -1; cur.base = -1; i = 0; do { unsigned int next_word = (unsigned int)*next_src++; next_word <<= 8; next_word |= (unsigned int)*next_src++; *next_dest++ = next_word; if (next_word == 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; } } i++; } while (next_src < src_end); if (cur.base != -1) { if (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);) { /* Are we inside the best run of 0x00's? */ if (i == best.base) { *tp++ = ':'; i += best.len; 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_ntop4(src+12, tp, sizeof tmp - (tp - tmp))) { return (NULL); } tp += strlen(tp); break; } tp += Snprintf(tp, sizeof tmp - (tp - tmp), "%x", words[i]); 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) { #ifndef WIN32 errno = ENOSPC; #endif return (NULL); } strncpy(dst, tmp, size); return (dst); } #endif