diff options
Diffstat (limited to 'lib/bind/inet/inet_cidr_ntop.c')
-rw-r--r-- | lib/bind/inet/inet_cidr_ntop.c | 263 |
1 files changed, 263 insertions, 0 deletions
diff --git a/lib/bind/inet/inet_cidr_ntop.c b/lib/bind/inet/inet_cidr_ntop.c new file mode 100644 index 0000000..645b3cd --- /dev/null +++ b/lib/bind/inet/inet_cidr_ntop.c @@ -0,0 +1,263 @@ +/* + * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC") + * Copyright (c) 1998,1999 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 ISC DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC 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[] = "$Id: inet_cidr_ntop.c,v 1.4.18.3 2006/10/11 02:32:47 marka Exp $"; +#endif + +#include "port_before.h" + +#include <sys/types.h> +#include <sys/socket.h> +#include <netinet/in.h> +#include <arpa/nameser.h> +#include <arpa/inet.h> + +#include <errno.h> +#include <stdio.h> +#include <string.h> +#include <stdlib.h> + +#include "port_after.h" + +#ifdef SPRINTF_CHAR +# define SPRINTF(x) strlen(sprintf/**/x) +#else +# define SPRINTF(x) ((size_t)sprintf x) +#endif + +static char * +inet_cidr_ntop_ipv4(const u_char *src, int bits, char *dst, size_t size); +static char * +inet_cidr_ntop_ipv6(const u_char *src, int bits, char *dst, size_t size); + +/*% + * char * + * inet_cidr_ntop(af, src, bits, dst, size) + * convert network address from network to presentation format. + * "src"'s size is determined from its "af". + * return: + * pointer to dst, or NULL if an error occurred (check errno). + * note: + * 192.5.5.1/28 has a nonzero host part, which means it isn't a network + * as called for by inet_net_ntop() but it can be a host address with + * an included netmask. + * author: + * Paul Vixie (ISC), October 1998 + */ +char * +inet_cidr_ntop(int af, const void *src, int bits, char *dst, size_t size) { + switch (af) { + case AF_INET: + return (inet_cidr_ntop_ipv4(src, bits, dst, size)); + case AF_INET6: + return (inet_cidr_ntop_ipv6(src, bits, dst, size)); + default: + errno = EAFNOSUPPORT; + return (NULL); + } +} + +static int +decoct(const u_char *src, int bytes, char *dst, size_t size) { + char *odst = dst; + char *t; + int b; + + for (b = 1; b <= bytes; b++) { + if (size < sizeof "255.") + return (0); + t = dst; + dst += SPRINTF((dst, "%u", *src++)); + if (b != bytes) { + *dst++ = '.'; + *dst = '\0'; + } + size -= (size_t)(dst - t); + } + return (dst - odst); +} + +/*% + * static char * + * inet_cidr_ntop_ipv4(src, bits, dst, size) + * convert IPv4 network address from network to presentation format. + * "src"'s size is determined from its "af". + * 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), October 1998 + */ +static char * +inet_cidr_ntop_ipv4(const u_char *src, int bits, char *dst, size_t size) { + char *odst = dst; + size_t len = 4; + size_t b; + size_t bytes; + + if ((bits < -1) || (bits > 32)) { + errno = EINVAL; + return (NULL); + } + + /* Find number of significant bytes in address. */ + if (bits == -1) + len = 4; + else + for (len = 1, b = 1 ; b < 4U; b++) + if (*(src + b)) + len = b + 1; + + /* Format whole octets plus nonzero trailing octets. */ + bytes = (((bits <= 0) ? 1 : bits) + 7) / 8; + if (len > bytes) + bytes = len; + b = decoct(src, bytes, dst, size); + if (b == 0U) + goto emsgsize; + dst += b; + size -= b; + + if (bits != -1) { + /* Format CIDR /width. */ + if (size < sizeof "/32") + goto emsgsize; + dst += SPRINTF((dst, "/%u", bits)); + } + + return (odst); + + emsgsize: + errno = EMSGSIZE; + return (NULL); +} + +static char * +inet_cidr_ntop_ipv6(const u_char *src, int bits, 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:255.255.255.255/128"]; + char *tp; + struct { int base, len; } best, cur; + u_int words[NS_IN6ADDRSZ / NS_INT16SZ]; + int i; + + if ((bits < -1) || (bits > 128)) { + errno = EINVAL; + return (NULL); + } + + /* + * 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 < NS_IN6ADDRSZ; i++) + words[i / 2] |= (src[i] << ((1 - (i % 2)) << 3)); + best.base = -1; + best.len = 0; + cur.base = -1; + cur.len = 0; + for (i = 0; i < (NS_IN6ADDRSZ / NS_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) { + 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 < (NS_IN6ADDRSZ / NS_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 == 7 && words[7] != 0x0001) || + (best.len == 5 && words[5] == 0xffff))) { + int n; + + if (src[15] || bits == -1 || bits > 120) + n = 4; + else if (src[14] || bits > 112) + n = 3; + else + n = 2; + n = decoct(src+12, n, tp, sizeof tmp - (tp - tmp)); + if (n == 0) { + errno = EMSGSIZE; + return (NULL); + } + tp += strlen(tp); + break; + } + tp += SPRINTF((tp, "%x", words[i])); + } + + /* Was it a trailing run of 0x00's? */ + if (best.base != -1 && (best.base + best.len) == + (NS_IN6ADDRSZ / NS_INT16SZ)) + *tp++ = ':'; + *tp = '\0'; + + if (bits != -1) + tp += SPRINTF((tp, "/%u", bits)); + + /* + * Check for overflow, copy, and we're done. + */ + if ((size_t)(tp - tmp) > size) { + errno = EMSGSIZE; + return (NULL); + } + strcpy(dst, tmp); + return (dst); +} + +/*! \file */ |