/* * Copyright (c) 1996,1999 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. */ #if defined(LIBC_SCCS) && !defined(lint) static const char rcsid[] = "$BINDId: inet_net_ntop.c,v 1.6 1999/01/08 19:23:42 vixie Exp $"; #endif #include #include #include #include #include #include #include #include #ifdef SPRINTF_CHAR # define SPRINTF(x) strlen(sprintf/**/x) #else # define SPRINTF(x) ((size_t)sprintf x) #endif static char * inet_net_ntop_ipv4 (const u_char *src, int bits, char *dst, size_t size) __THROW; /* * char * * inet_net_ntop(af, src, bits, dst, size) * convert network number from network to presentation format. * generates CIDR style result always. * return: * pointer to dst, or NULL if an error occurred (check errno). * author: * Paul Vixie (ISC), July 1996 */ char * inet_net_ntop(af, src, bits, dst, size) int af; const void *src; int bits; char *dst; size_t size; { switch (af) { case AF_INET: return (inet_net_ntop_ipv4(src, bits, dst, size)); default: __set_errno (EAFNOSUPPORT); return (NULL); } } /* * static char * * inet_net_ntop_ipv4(src, bits, dst, size) * convert IPv4 network number from network to presentation format. * generates CIDR style result always. * return: * pointer to dst, or NULL if an error occurred (check errno). * note: * network byte order assumed. this means 192.5.5.240/28 has * 0b11110000 in its fourth octet. * author: * Paul Vixie (ISC), July 1996 */ static char * inet_net_ntop_ipv4(src, bits, dst, size) const u_char *src; int bits; char *dst; size_t size; { char *odst = dst; char *t; u_int m; int b; if (bits < 0 || bits > 32) { __set_errno (EINVAL); return (NULL); } if (bits == 0) { if (size < sizeof "0") goto emsgsize; *dst++ = '0'; size--; *dst = '\0'; } /* Format whole octets. */ for (b = bits / 8; b > 0; b--) { if (size < sizeof "255.") goto emsgsize; t = dst; dst += SPRINTF((dst, "%u", *src++)); if (b > 1) { *dst++ = '.'; *dst = '\0'; } size -= (size_t)(dst - t); } /* Format partial octet. */ b = bits % 8; if (b > 0) { if (size < sizeof ".255") goto emsgsize; t = dst; if (dst != odst) *dst++ = '.'; m = ((1 << b) - 1) << (8 - b); dst += SPRINTF((dst, "%u", *src & m)); size -= (size_t)(dst - t); } /* Format CIDR /width. */ if (size < sizeof "/32") goto emsgsize; dst += SPRINTF((dst, "/%u", bits)); return (odst); emsgsize: __set_errno (EMSGSIZE); return (NULL); }