2005-04-17 02:20:36 +04:00
/*
* linux / fs / binfmt_script . c
*
2007-10-20 01:21:04 +04:00
* Copyright ( C ) 1996 Martin von Löwis
2005-04-17 02:20:36 +04:00
* original # ! - checking implemented by tytso .
*/
# include <linux/module.h>
# include <linux/string.h>
# include <linux/stat.h>
# include <linux/slab.h>
# include <linux/binfmts.h>
# include <linux/init.h>
# include <linux/file.h>
# include <linux/err.h>
# include <linux/fs.h>
static int load_script ( struct linux_binprm * bprm , struct pt_regs * regs )
{
char * cp , * i_name , * i_arg ;
struct file * file ;
char interp [ BINPRM_BUF_SIZE ] ;
int retval ;
if ( ( bprm - > buf [ 0 ] ! = ' # ' ) | | ( bprm - > buf [ 1 ] ! = ' ! ' ) | | ( bprm - > sh_bang ) )
return - ENOEXEC ;
/*
* This section does the # ! interpretation .
* Sorta complicated , but hopefully it will work . - TYT
*/
bprm - > sh_bang + + ;
allow_write_access ( bprm - > file ) ;
fput ( bprm - > file ) ;
bprm - > file = NULL ;
bprm - > buf [ BINPRM_BUF_SIZE - 1 ] = ' \0 ' ;
if ( ( cp = strchr ( bprm - > buf , ' \n ' ) ) = = NULL )
cp = bprm - > buf + BINPRM_BUF_SIZE - 1 ;
* cp = ' \0 ' ;
while ( cp > bprm - > buf ) {
cp - - ;
if ( ( * cp = = ' ' ) | | ( * cp = = ' \t ' ) )
* cp = ' \0 ' ;
else
break ;
}
for ( cp = bprm - > buf + 2 ; ( * cp = = ' ' ) | | ( * cp = = ' \t ' ) ; cp + + ) ;
if ( * cp = = ' \0 ' )
return - ENOEXEC ; /* No interpreter name found */
i_name = cp ;
i_arg = NULL ;
for ( ; * cp & & ( * cp ! = ' ' ) & & ( * cp ! = ' \t ' ) ; cp + + )
/* nothing */ ;
while ( ( * cp = = ' ' ) | | ( * cp = = ' \t ' ) )
* cp + + = ' \0 ' ;
if ( * cp )
i_arg = cp ;
strcpy ( interp , i_name ) ;
/*
* OK , we ' ve parsed out the interpreter name and
* ( optional ) argument .
* Splice in ( 1 ) the interpreter ' s name for argv [ 0 ]
* ( 2 ) ( optional ) argument to interpreter
* ( 3 ) filename of shell script ( replace argv [ 0 ] )
*
* This is done in reverse order , because of how the
* user environment and arguments are stored .
*/
2007-07-19 12:48:16 +04:00
retval = remove_arg_zero ( bprm ) ;
if ( retval )
return retval ;
2005-04-17 02:20:36 +04:00
retval = copy_strings_kernel ( 1 , & bprm - > interp , bprm ) ;
if ( retval < 0 ) return retval ;
bprm - > argc + + ;
if ( i_arg ) {
retval = copy_strings_kernel ( 1 , & i_arg , bprm ) ;
if ( retval < 0 ) return retval ;
bprm - > argc + + ;
}
retval = copy_strings_kernel ( 1 , & i_name , bprm ) ;
if ( retval ) return retval ;
bprm - > argc + + ;
bprm - > interp = interp ;
/*
* OK , now restart the process with the interpreter ' s dentry .
*/
file = open_exec ( interp ) ;
if ( IS_ERR ( file ) )
return PTR_ERR ( file ) ;
bprm - > file = file ;
retval = prepare_binprm ( bprm ) ;
if ( retval < 0 )
return retval ;
return search_binary_handler ( bprm , regs ) ;
}
static struct linux_binfmt script_format = {
. module = THIS_MODULE ,
. load_binary = load_script ,
} ;
static int __init init_script_binfmt ( void )
{
return register_binfmt ( & script_format ) ;
}
static void __exit exit_script_binfmt ( void )
{
unregister_binfmt ( & script_format ) ;
}
core_initcall ( init_script_binfmt ) ;
module_exit ( exit_script_binfmt ) ;
MODULE_LICENSE ( " GPL " ) ;