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/*
* This file or a portion of this file is licensed under the terms of
* the Globus Toolkit Public License, found in file GTPL, or at
* http://www.globus.org/toolkit/download/license.html. This notice must
* appear in redistributions of this file, with or without modification.
*
* Redistributions of this Software, with or without modification, must
* reproduce the GTPL in: (1) the Software, or (2) the Documentation or
* some other similar material which is provided with the Software (if
* any).
*
* Copyright 1999-2004 University of Chicago and The University of
* Southern California. All rights reserved.
*/
#include "mynss.h"
static const char* RCS_ID =
"$Id: mynss.c 50 2007-05-19 00:48:32Z gmehta $";
#ifdef LINUX
#include <setjmp.h>
#include <errno.h>
#include <memory.h>
#include <string.h>
#include "mysignal.h"
/*
* Linux statically linked binaries do not like libnss function calls.
*/
volatile sig_atomic_t noSymbolicLookups;
static volatile sig_atomic_t canJump;
static sigjmp_buf jump;
static
SIGRETTYPE
sigsegv_handler( SIGPARAM signo )
{
if ( canJump == 0 ) return; /* unexpected signal */
noSymbolicLookups = signo;
canJump = 0;
siglongjmp( jump, 1 );
}
static
int
setup_sigsegv( struct sigaction* old, struct sigaction* new )
{
memset( old, 0, sizeof(*old) );
memset( new, 0, sizeof(*new) );
new->sa_handler = sigsegv_handler;
sigemptyset( &(new->sa_mask) );
#ifdef SA_INTERRUPT
new->sa_flags |= SA_INTERRUPT; /* SunOS, obsoleted by POSIX */
#endif
return sigaction( SIGSEGV, new, old );
}
struct passwd*
wrap_getpwuid( uid_t uid )
{
struct sigaction old_segv, new_segv;
struct passwd* result;
if ( noSymbolicLookups ) return NULL;
if ( sigsetjmp( jump, 1 ) ) {
errno = ELIBACC;
return NULL;
}
canJump = 1;
setup_sigsegv( &old_segv, &new_segv );
result = getpwuid(uid);
sigaction( SIGSEGV, &old_segv, NULL );
return ( noSymbolicLookups ? NULL : result );
}
struct group*
wrap_getgrgid( gid_t gid )
{
struct sigaction old_segv, new_segv;
struct group* result;
if ( noSymbolicLookups ) return NULL;
if ( sigsetjmp( jump, 1 ) ) {
errno = ELIBACC;
return NULL;
}
canJump = 1;
setup_sigsegv( &old_segv, &new_segv );
result = getgrgid(gid);
sigaction( SIGSEGV, &old_segv, NULL );
return ( noSymbolicLookups ? NULL : result );
}
struct hostent*
wrap_gethostbyaddr( const char* addr, int len, int type )
{
struct sigaction old_segv, new_segv;
struct hostent* result;
if ( noSymbolicLookups ) return NULL;
if ( sigsetjmp( jump, 1 ) ) {
h_errno = NETDB_INTERNAL;
errno = ELIBACC;
return NULL;
}
canJump = 1;
setup_sigsegv( &old_segv, &new_segv );
result = gethostbyaddr(addr,len,type);
sigaction( SIGSEGV, &old_segv, NULL );
return ( noSymbolicLookups ? NULL : result );
}
#endif /* LINUX */
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