minix/lib/libc/nameser/ns_samedomain.c
Ben Gras 2fe8fb192f Full switch to clang/ELF. Drop ack. Simplify.
There is important information about booting non-ack images in
docs/UPDATING. ack/aout-format images can't be built any more, and
booting clang/ELF-format ones is a little different. Updating to the
new boot monitor is recommended.

Changes in this commit:

	. drop boot monitor -> allowing dropping ack support
	. facility to copy ELF boot files to /boot so that old boot monitor
	  can still boot fairly easily, see UPDATING
	. no more ack-format libraries -> single-case libraries
	. some cleanup of OBJECT_FMT, COMPILER_TYPE, etc cases
	. drop several ack toolchain commands, but not all support
	  commands (e.g. aal is gone but acksize is not yet).
	. a few libc files moved to netbsd libc dir
	. new /bin/date as minix date used code in libc/
	. test compile fix
	. harmonize includes
	. /usr/lib is no longer special: without ack, /usr/lib plays no
	  kind of special bootstrapping role any more and bootstrapping
	  is done exclusively through packages, so releases depend even
	  less on the state of the machine making them now.
	. rename nbsd_lib* to lib*
	. reduce mtree
2012-02-14 14:52:02 +01:00

216 lines
4.9 KiB
C

/* $NetBSD: ns_samedomain.c,v 1.6 2009/04/12 17:07:17 christos Exp $ */
/*
* Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
* Copyright (c) 1995,1999 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.
*/
#include <sys/cdefs.h>
#ifndef lint
#ifdef notdef
static const char rcsid[] = "Id: ns_samedomain.c,v 1.6 2005/04/27 04:56:40 sra Exp";
#else
__RCSID("$NetBSD: ns_samedomain.c,v 1.6 2009/04/12 17:07:17 christos Exp $");
#endif
#endif
#include "port_before.h"
#include <sys/types.h>
#include <arpa/nameser.h>
#include <errno.h>
#include <string.h>
#include "port_after.h"
#ifndef _LIBC
/*%
* Check whether a name belongs to a domain.
*
* Inputs:
*\li a - the domain whose ancestory is being verified
*\li b - the potential ancestor we're checking against
*
* Return:
*\li boolean - is a at or below b?
*
* Notes:
*\li Trailing dots are first removed from name and domain.
* Always compare complete subdomains, not only whether the
* domain name is the trailing string of the given name.
*
*\li "host.foobar.top" lies in "foobar.top" and in "top" and in ""
* but NOT in "bar.top"
*/
int
ns_samedomain(const char *a, const char *b) {
size_t la, lb;
int diff, i, escaped;
const char *cp;
la = strlen(a);
lb = strlen(b);
/* Ignore a trailing label separator (i.e. an unescaped dot) in 'a'. */
if (la != 0U && a[la - 1] == '.') {
escaped = 0;
/* Note this loop doesn't get executed if la==1. */
for (i = la - 2; i >= 0; i--)
if (a[i] == '\\') {
if (escaped)
escaped = 0;
else
escaped = 1;
} else
break;
if (!escaped)
la--;
}
/* Ignore a trailing label separator (i.e. an unescaped dot) in 'b'. */
if (lb != 0U && b[lb - 1] == '.') {
escaped = 0;
/* note this loop doesn't get executed if lb==1 */
for (i = lb - 2; i >= 0; i--)
if (b[i] == '\\') {
if (escaped)
escaped = 0;
else
escaped = 1;
} else
break;
if (!escaped)
lb--;
}
/* lb == 0 means 'b' is the root domain, so 'a' must be in 'b'. */
if (lb == 0U)
return (1);
/* 'b' longer than 'a' means 'a' can't be in 'b'. */
if (lb > la)
return (0);
/* 'a' and 'b' being equal at this point indicates sameness. */
if (lb == la)
return (strncasecmp(a, b, lb) == 0);
/* Ok, we know la > lb. */
diff = la - lb;
/*
* If 'a' is only 1 character longer than 'b', then it can't be
* a subdomain of 'b' (because of the need for the '.' label
* separator).
*/
if (diff < 2)
return (0);
/*
* If the character before the last 'lb' characters of 'b'
* isn't '.', then it can't be a match (this lets us avoid
* having "foobar.com" match "bar.com").
*/
if (a[diff - 1] != '.')
return (0);
/*
* We're not sure about that '.', however. It could be escaped
* and thus not a really a label separator.
*/
escaped = 0;
for (i = diff - 2; i >= 0; i--)
if (a[i] == '\\') {
if (escaped)
escaped = 0;
else
escaped = 1;
} else
break;
if (escaped)
return (0);
/* Now compare aligned trailing substring. */
cp = a + diff;
return (strncasecmp(cp, b, lb) == 0);
}
/*%
* is "a" a subdomain of "b"?
*/
int
ns_subdomain(const char *a, const char *b) {
return (ns_samename(a, b) != 1 && ns_samedomain(a, b));
}
#endif
/*%
* make a canonical copy of domain name "src"
*
* notes:
* \code
* foo -> foo.
* foo. -> foo.
* foo.. -> foo.
* foo\. -> foo\..
* foo\\. -> foo\\.
* \endcode
*/
int
ns_makecanon(const char *src, char *dst, size_t dstsize) {
size_t n = strlen(src);
if (n + sizeof "." > dstsize) { /*%< Note: sizeof == 2 */
errno = EMSGSIZE;
return (-1);
}
strcpy(dst, src);
while (n >= 1U && dst[n - 1] == '.') /*%< Ends in "." */
if (n >= 2U && dst[n - 2] == '\\' && /*%< Ends in "\." */
(n < 3U || dst[n - 3] != '\\')) /*%< But not "\\." */
break;
else
dst[--n] = '\0';
dst[n++] = '.';
dst[n] = '\0';
return (0);
}
/*%
* determine whether domain name "a" is the same as domain name "b"
*
* return:
*\li -1 on error
*\li 0 if names differ
*\li 1 if names are the same
*/
int
ns_samename(const char *a, const char *b) {
char ta[NS_MAXDNAME], tb[NS_MAXDNAME];
if (ns_makecanon(a, ta, sizeof ta) < 0 ||
ns_makecanon(b, tb, sizeof tb) < 0)
return (-1);
if (strcasecmp(ta, tb) == 0)
return (1);
else
return (0);
}
/*! \file */