network_io/unix/inet_ntop.c - apr - Git at Google

 /* 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.
  */

 #include "apr_private.h"
 #include "apr_arch_networkio.h"
 #include "apr_strings.h"

 #if APR_HAVE_SYS_TYPES_H
 #include <sys/types.h>
 #endif
 #if APR_HAVE_SYS_SOCKET_H
 #include <sys/socket.h>
 #endif
 #if APR_HAVE_NETINET_IN_H
 #include <netinet/in.h>
 #endif
 #if APR_HAVE_ARPA_INET_H
 #include <arpa/inet.h>
 #endif
 #include <string.h>
 #if APR_HAVE_ERRNO_H
 #include <errno.h>
 #endif
 #include <stdio.h>

 #ifndef IN6ADDRSZ
 #define IN6ADDRSZ   16
 #endif

 #ifndef INT16SZ
 #define INT16SZ sizeof(apr_int16_t)
 #endif

 #ifndef __P
 #define __P(x) x
 #endif

 #if !defined(EAFNOSUPPORT) && defined(WSAEAFNOSUPPORT)
 #define EAFNOSUPPORT WSAEAFNOSUPPORT
 #endif

 /*
  * WARNING: Don't even consider trying to compile this on a system where
  * sizeof(int) < 4.  sizeof(int) > 4 is fine; all the world's not a VAX.
  */

 static const char *inet_ntop4 __P((const unsigned char *src, char *dst, apr_size_t size));
 #if APR_HAVE_IPV6
 static const char *inet_ntop6 __P((const unsigned char *src, char *dst, apr_size_t size));
 #endif

 /* char *
  * inet_ntop(af, src, dst, size)
  *	convert a network format address to presentation format.
  * return:
  *	pointer to presentation format address (`dst'), or NULL (see errno).
  * author:
  *	Paul Vixie, 1996.
  */
 const char *
 apr_inet_ntop(int af, const void *src, char *dst, apr_size_t size)
 {
 	switch (af) {
 	case AF_INET:
 		return (inet_ntop4(src, dst, size));
 #if APR_HAVE_IPV6
 	case AF_INET6:
 		return (inet_ntop6(src, dst, size));
 #endif
 	default:
 		errno = EAFNOSUPPORT;
 		return (NULL);
 	}
 	/* NOTREACHED */
 }

 /* const char *
  * inet_ntop4(src, dst, size)
  *	format an IPv4 address, more or less like inet_ntoa()
  * return:
  *	`dst' (as a const)
  * notes:
  *	(1) uses no statics
  *	(2) takes a u_char* not an in_addr as input
  * author:
  *	Paul Vixie, 1996.
  */
 static const char *
 inet_ntop4(const unsigned char *src, char *dst, apr_size_t size)
 {
 	const apr_size_t MIN_SIZE = 16; /* space for 255.255.255.255\0 */
 	int n = 0;
 	char *next = dst;

 	if (size < MIN_SIZE) {
 	    errno = ENOSPC;
 	    return NULL;
 	}
 	do {
 	    unsigned char u = *src++;
 	    if (u > 99) {
 		*next++ = '0' + u/100;
 		u %= 100;
 		*next++ = '0' + u/10;
 		u %= 10;
 	    }
 	    else if (u > 9) {
 		*next++ = '0' + u/10;
 		u %= 10;
 	    }
 	    *next++ = '0' + u;
 	    *next++ = '.';
 	    n++;
 	} while (n < 4);
 	*--next = 0;
 	return dst;
 }

 #if APR_HAVE_IPV6
 /* const char *
  * inet_ntop6(src, dst, size)
  *	convert IPv6 binary address into presentation (printable) format
  * author:
  *	Paul Vixie, 1996.
  */
 static const char *
 inet_ntop6(const unsigned char *src, char *dst, apr_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"], *tp;
     struct { int base, len; } best, cur;
     unsigned int words[IN6ADDRSZ / INT16SZ];
     int i;
     const unsigned char *next_src, *src_end;
     unsigned int *next_dest;

     /*
      * Preprocess:
      *	Copy the input (bytewise) array into a wordwise array.
      *	Find the longest run of 0x00's in src[] for :: shorthanding.
      */
     next_src = src;
     src_end = src + IN6ADDRSZ;
     next_dest = words;
     best.base = -1;
     cur.base = -1;
     cur.len = best.len = 0; /* silence gcc4 warning */
     i = 0;
     do {
         unsigned int next_word = (unsigned int)*next_src++;
         next_word <<= 8;
         next_word |= (unsigned int)*next_src++;
         *next_dest++ = next_word;

         if (next_word == 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;
             }
         }

         i++;
     } while (next_src < src_end);

     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 < (IN6ADDRSZ / INT16SZ);) {
         /* Are we inside the best run of 0x00's? */
         if (i == best.base) {
             *tp++ = ':';
             i += best.len;
             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))) {
                 return (NULL);
             }
             tp += strlen(tp);
             break;
         }
         tp += apr_snprintf(tp, sizeof tmp - (tp - tmp), "%x", words[i]);
         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 ((apr_size_t)(tp - tmp) > size) {
         errno = ENOSPC;
         return (NULL);
     }
     strcpy(dst, tmp);
     return (dst);
 }
 #endif
	/* 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.
	*/

	#include "apr_private.h"
	#include "apr_arch_networkio.h"
	#include "apr_strings.h"

	#if APR_HAVE_SYS_TYPES_H
	#include <sys/types.h>
	#endif
	#if APR_HAVE_SYS_SOCKET_H
	#include <sys/socket.h>
	#endif
	#if APR_HAVE_NETINET_IN_H
	#include <netinet/in.h>
	#endif
	#if APR_HAVE_ARPA_INET_H
	#include <arpa/inet.h>
	#endif
	#include <string.h>
	#if APR_HAVE_ERRNO_H
	#include <errno.h>
	#endif
	#include <stdio.h>

	#ifndef IN6ADDRSZ
	#define IN6ADDRSZ 16
	#endif

	#ifndef INT16SZ
	#define INT16SZ sizeof(apr_int16_t)
	#endif

	#ifndef __P
	#define __P(x) x
	#endif

	#if !defined(EAFNOSUPPORT) && defined(WSAEAFNOSUPPORT)
	#define EAFNOSUPPORT WSAEAFNOSUPPORT
	#endif

	/*
	* WARNING: Don't even consider trying to compile this on a system where
	* sizeof(int) < 4. sizeof(int) > 4 is fine; all the world's not a VAX.
	*/

	static const char inet_ntop4 __P((const unsigned char src, char *dst, apr_size_t size));
	#if APR_HAVE_IPV6
	static const char inet_ntop6 __P((const unsigned char src, char *dst, apr_size_t size));
	#endif

	/* char *
	* inet_ntop(af, src, dst, size)
	* convert a network format address to presentation format.
	* return:
	* pointer to presentation format address (`dst'), or NULL (see errno).
	* author:
	* Paul Vixie, 1996.
	*/
	const char *
	apr_inet_ntop(int af, const void src, char dst, apr_size_t size)
	{
	switch (af) {
	case AF_INET:
	return (inet_ntop4(src, dst, size));
	#if APR_HAVE_IPV6
	case AF_INET6:
	return (inet_ntop6(src, dst, size));
	#endif
	default:
	errno = EAFNOSUPPORT;
	return (NULL);
	}
	/* NOTREACHED */
	}

	/* const char *
	* inet_ntop4(src, dst, size)
	* format an IPv4 address, more or less like inet_ntoa()
	* return:
	* `dst' (as a const)
	* notes:
	* (1) uses no statics
	* (2) takes a u_char* not an in_addr as input
	* author:
	* Paul Vixie, 1996.
	*/
	static const char *
	inet_ntop4(const unsigned char src, char dst, apr_size_t size)
	{
	const apr_size_t MIN_SIZE = 16; /* space for 255.255.255.255\0 */
	int n = 0;
	char *next = dst;

	if (size < MIN_SIZE) {
	errno = ENOSPC;
	return NULL;
	}
	do {
	unsigned char u = *src++;
	if (u > 99) {
	*next++ = '0' + u/100;
	u %= 100;
	*next++ = '0' + u/10;
	u %= 10;
	}
	else if (u > 9) {
	*next++ = '0' + u/10;
	u %= 10;
	}
	*next++ = '0' + u;
	*next++ = '.';
	n++;
	} while (n < 4);
	*--next = 0;
	return dst;
	}

	#if APR_HAVE_IPV6
	/* const char *
	* inet_ntop6(src, dst, size)
	* convert IPv6 binary address into presentation (printable) format
	* author:
	* Paul Vixie, 1996.
	*/
	static const char *
	inet_ntop6(const unsigned char src, char dst, apr_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"], *tp;
	struct { int base, len; } best, cur;
	unsigned int words[IN6ADDRSZ / INT16SZ];
	int i;
	const unsigned char next_src, src_end;
	unsigned int *next_dest;

	/*
	* Preprocess:
	* Copy the input (bytewise) array into a wordwise array.
	* Find the longest run of 0x00's in src[] for :: shorthanding.
	*/
	next_src = src;
	src_end = src + IN6ADDRSZ;
	next_dest = words;
	best.base = -1;
	cur.base = -1;
	cur.len = best.len = 0; /* silence gcc4 warning */
	i = 0;
	do {
	unsigned int next_word = (unsigned int)*next_src++;
	next_word <<= 8;
	next_word \|= (unsigned int)*next_src++;
	*next_dest++ = next_word;

	if (next_word == 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;
	}
	}

	i++;
	} while (next_src < src_end);

	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 < (IN6ADDRSZ / INT16SZ);) {
	/* Are we inside the best run of 0x00's? */
	if (i == best.base) {
	*tp++ = ':';
	i += best.len;
	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))) {
	return (NULL);
	}
	tp += strlen(tp);
	break;
	}
	tp += apr_snprintf(tp, sizeof tmp - (tp - tmp), "%x", words[i]);
	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 ((apr_size_t)(tp - tmp) > size) {
	errno = ENOSPC;
	return (NULL);
	}
	strcpy(dst, tmp);
	return (dst);
	}
	#endif