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Diffstat (limited to 'lib/inet_ntop.c')
| -rw-r--r-- | lib/inet_ntop.c | 199 |
1 files changed, 199 insertions, 0 deletions
diff --git a/lib/inet_ntop.c b/lib/inet_ntop.c new file mode 100644 index 000000000..1ff975667 --- /dev/null +++ b/lib/inet_ntop.c @@ -0,0 +1,199 @@ +/* + * Copyright (C) 1996-2001 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. + */ +/* + * Original code by Paul Vixie. "curlified" by Gisle Vanem. + */ + +#include "setup.h" + +#ifndef HAVE_INET_NTOP + +#ifdef HAVE_SYS_PARAM_H +#include <sys/param.h> +#endif +#ifdef HAVE_NETINET_IN_H +#include <netinet/in.h> +#endif +#ifdef HAVE_ARPA_INET_H +#include <arpa/inet.h> +#endif + +#define _MPRINTF_REPLACE /* use our functions only */ +#include <curl/mprintf.h> + +#include "inet_ntop.h" + +#define IN6ADDRSZ 16 +#define INADDRSZ 4 +#define INT16SZ 2 + +/* + * Format an IPv4 address, more or less like inet_ntoa(). + * + * Returns `dst' (as a const) + * Note: + * - uses no statics + * - takes a unsigned char* not an in_addr as input + */ +static char *inet_ntop4 (const unsigned char *src, char *dst, size_t size) +{ + char tmp[sizeof "255.255.255.255"]; + size_t len; + + DEBUGASSERT(size >= 16); + + tmp[0] = '\0'; + (void)snprintf(tmp, sizeof(tmp), "%d.%d.%d.%d", + ((int)((unsigned char)src[0])) & 0xff, + ((int)((unsigned char)src[1])) & 0xff, + ((int)((unsigned char)src[2])) & 0xff, + ((int)((unsigned char)src[3])) & 0xff); + + len = strlen(tmp); + if(len == 0 || len >= size) { + SET_ERRNO(ENOSPC); + return (NULL); + } + strcpy(dst, tmp); + return dst; +} + +#ifdef ENABLE_IPV6 +/* + * Convert IPv6 binary address into presentation (printable) format. + */ +static 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")]; + char *tp; + struct { + long base; + long len; + } best, cur; + unsigned 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; + best.len = 0; + cur.len = 0; + + 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_ntop4(src+12, tp, sizeof(tmp) - (tp - tmp))) { + SET_ERRNO(ENOSPC); + return (NULL); + } + tp += strlen(tp); + break; + } + tp += snprintf(tp, 5, "%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) { + SET_ERRNO(ENOSPC); + return (NULL); + } + strcpy(dst, tmp); + return dst; +} +#endif /* ENABLE_IPV6 */ + +/* + * Convert a network format address to presentation format. + * + * Returns pointer to presentation format address (`buf'). + * Returns NULL on error and errno set with the specific + * error, EAFNOSUPPORT or ENOSPC. + * + * On Windows we store the error in the thread errno, not + * in the winsock error code. This is to avoid losing the + * actual last winsock error. So use macro ERRNO to fetch the + * errno this function sets when returning NULL, not SOCKERRNO. + */ +char *Curl_inet_ntop(int af, const void *src, char *buf, size_t size) +{ + switch (af) { + case AF_INET: + return inet_ntop4((const unsigned char*)src, buf, size); +#ifdef ENABLE_IPV6 + case AF_INET6: + return inet_ntop6((const unsigned char*)src, buf, size); +#endif + default: + SET_ERRNO(EAFNOSUPPORT); + return NULL; + } +} +#endif /* HAVE_INET_NTOP */ |