diff options
Diffstat (limited to 'lib/inet_ntop.c')
| -rw-r--r-- | lib/inet_ntop.c | 189 |
1 files changed, 189 insertions, 0 deletions
diff --git a/lib/inet_ntop.c b/lib/inet_ntop.c new file mode 100644 index 000000000..22c053e17 --- /dev/null +++ b/lib/inet_ntop.c @@ -0,0 +1,189 @@ +/* + * 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_SYS_TYPES_H +#include <sys/types.h> +#endif +#ifdef HAVE_SYS_SOCKET_H +#include <sys/socket.h> +#endif +#ifdef HAVE_NETINET_IN_H +#include <netinet/in.h> +#endif +#ifdef HAVE_ARPA_INET_H +#include <arpa/inet.h> +#endif +#include <string.h> +#include <errno.h> + +#include "inet_ntop.h" + +#define IN6ADDRSZ 16 +#define INADDRSZ 4 +#define INT16SZ 2 + +#ifdef WIN32 +#define EAFNOSUPPORT WSAEAFNOSUPPORT +#define SET_ERRNO(e) WSASetLastError(errno = (e)) +#else +#define SET_ERRNO(e) errno = e +#endif + +/* + * Format an IPv4 address, more or less like inet_ntoa(). + * + * Returns `dst' (as a const) + * Note: + * - uses no statics + * - takes a u_char* not an in_addr as input + */ +static const char *inet_ntop4 (const u_char *src, char *dst, size_t size) +{ +#ifdef HAVE_INET_NTOA_R + return inet_ntoa_r(*(struct in_addr*)src, dst, size); +#else + const char *addr = inet_ntoa(*(struct in_addr*)src); + + if (strlen(addr) >= size) + { + SET_ERRNO(ENOSPC); + return (NULL); + } + return strcpy(dst, addr); +#endif +} + +#ifdef ENABLE_IPV6 +/* + * Convert IPv6 binary address into presentation (printable) format. + */ +static const char *inet_ntop6 (const u_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; + u_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; + 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 += sprintf (tp, "%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); + } + return strcpy (dst, tmp); +} +#endif /* ENABLE_IPV6 */ + +/* + * Convert a network format address to presentation format. + * + * Returns pointer to presentation format address (`dst'), + * Returns NULL on error (see errno). + */ +const char *Curl_inet_ntop(int af, const void *src, char *buf, size_t size) +{ + switch (af) { + case AF_INET: + return inet_ntop4((const u_char*)src, buf, size); +#ifdef ENABLE_IPV6 + case AF_INET6: + return inet_ntop6((const u_char*)src, buf, size); +#endif + default: + SET_ERRNO(EAFNOSUPPORT); + return NULL; + } +} +#endif /* HAVE_INET_NTOP */ |