diff options
Diffstat (limited to 'resolv/inet_net_ntop.c')
-rw-r--r-- | resolv/inet_net_ntop.c | 139 |
1 files changed, 139 insertions, 0 deletions
diff --git a/resolv/inet_net_ntop.c b/resolv/inet_net_ntop.c new file mode 100644 index 0000000000..80abefcba7 --- /dev/null +++ b/resolv/inet_net_ntop.c @@ -0,0 +1,139 @@ +/* + * 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. + */ + +#if defined(LIBC_SCCS) && !defined(lint) +static const char rcsid[] = "$Id$"; +#endif + +#include <sys/types.h> +#include <sys/socket.h> +#include <netinet/in.h> +#include <arpa/inet.h> + +#include <errno.h> +#include <stdio.h> +#include <string.h> +#include <stdlib.h> + +#ifdef SPRINTF_CHAR +# define SPRINTF(x) strlen(sprintf/**/x) +#else +# define SPRINTF(x) ((size_t)sprintf x) +#endif + +static char * inet_net_ntop_ipv4 __P((const u_char *src, int bits, + char *dst, size_t size)); + +/* + * 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: + 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 + * 0x11110000 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) { + errno = EINVAL; + return (NULL); + } + if (bits == 0) { + if (size < sizeof "0") + goto emsgsize; + *dst++ = '0'; + *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: + errno = EMSGSIZE; + return (NULL); +} |