/* Portions of this code are
* Copyright (c) 1985 Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms are permitted provided
* that: (1) source distributions retain this entire copyright notice and
* comment, and (2) distributions including binaries display the following
* acknowledgement: ``This product includes software developed by the
* University of California, Berkeley and its contributors'' in the
* documentation or other materials provided with the distribution and in
* all advertising materials mentioning features or use of this software.
* Neither the name of the University nor the names of its contributors may
* be used to endorse or promote products derived from this software without
* specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/
/* Portions of this code are
* Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
* Copyright (c) 1996,1999 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.
*/
/* Portions of this code are
* Copyright (c) 2005 RIPE NCC, Olaf Kolkman
*
*
* All Rights Reserved
*
* Permission to use, copy, modify, and distribute this software and
* its documentation for any purpose and without fee is hereby
* granted, provided that the above copyright notice appear in all
* copies and that both that copyright notice and this permission
* notice appear in supporting documentation, and that the name of the
* author not be used in advertising or publicity pertaining to
* distribution of the software without specific, written prior
* permission.
*
*
* THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
* INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS; IN
* NO EVENT SHALL AUTHOR BE LIABLE FOR ANY SPECIAL, 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 <stdio.h>
#include "./netdns.h"
#include <sys/types.h>
static int special(int);
static int printable(int);
static const char digits[] = "0123456789";
/*
* Expand compressed domain name 'comp_dn' to full domain name.
* 'msg' is a pointer to the begining of the message,
* 'eomorig' points to the first location after the message,
* 'exp_dn' is a pointer to a buffer of size 'length' for the result.
* Return size of compressed name or -1 if there was an error.
*/
int netdns_dn_expand(msg, eomorig, comp_dn, exp_dn, length)
u_char *msg, *eomorig, *comp_dn, *exp_dn;
int length;
{
register u_char *cp, *dn;
register int n, c;
u_char *eom;
int len = -1, checked = 0;
dn = exp_dn;
cp = comp_dn;
eom = exp_dn + length;
/*
* fetch next label in domain name
*/
while ( (n = *cp++) ) {
/*
* Check for indirection
*/
switch (n & INDIR_MASK) {
case 0:
if (dn != exp_dn) {
if (dn >= eom)
return (-1);
*dn++ = '.';
}
if (dn+n >= eom)
return (-1);
checked += n + 1;
while (--n >= 0) {
c = *cp++;
if (special(c)) {
if (dn + 1 >= eom) {
return (-1);
}
*dn++ = '\\';
*dn++ = (char)c;
}else if (!printable(c)) {
if (dn + 3 >= eom) {
return (-1);
}
*dn++ = '\\';
*dn++ = digits[c / 100];
*dn++ = digits[(c % 100) / 10];
*dn++ = digits[c % 10];
} else {
if (dn >= eom) {
return (-1);
}
*dn++ = (char)c;
}
if (cp >= eomorig)/* out of range */
return(-1);
}
break;
case INDIR_MASK:
if (len < 0)
len = cp - comp_dn + 1;
cp = msg + (((n & 0x3f) << 8) | (*cp & 0xff));
if (cp < msg || cp >= eomorig)/* out of range */
return(-1);
checked += 2;
/*
* Check for loops in the compressed name;
* if we've looked at the whole message,
* there must be a loop.
*/
if (checked >= eomorig - msg)
return (-1);
break;
default:
return (-1);/* flag error */
}
}
*dn = '\0';
if (len < 0)
len = cp - comp_dn;
return (len);
}
/*
* special(ch)
* Thinking in noninternationalized USASCII (per the DNS spec),
* is this characted special ("in need of quoting") ?
* return:
* boolean.
*/
static int
special(int ch) {
switch (ch) {
case 0x22: /* '"' */
case 0x2E: /* '.' */
case 0x3B: /* ';' */
case 0x5C: /* '\\' */
case 0x28: /* '(' */
case 0x29: /* ')' */
/* Special modifiers in zone files. */
case 0x40: /* '@' */
case 0x24: /* '$' */
return (1);
default:
return (0);
}
}
/*
* printable(ch)
* Thinking in noninternationalized USASCII (per the DNS spec),
* is this character visible and not a space when printed ?
* return:
* boolean.
*/
static int
printable(int ch) {
return (ch > 0x20 && ch < 0x7f);
}