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* linux/fs/binfmt_script.c
*
* Copyright (C) 1996 Martin von Löwis
* original #!-checking implemented by tytso.
*/
#include <linux/module.h>
#include <linux/string.h>
#include <linux/stat.h>
#include <linux/malloc.h>
#include <linux/binfmts.h>
#include <linux/init.h>
static int do_load_script(struct linux_binprm *bprm,struct pt_regs *regs)
{
char *cp, *i_name, *i_name_start, *i_arg;
struct dentry * dentry;
char interp[128];
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++;
dput(bprm->dentry);
bprm->dentry = NULL;
bprm->buf[127] = '\0';
if ((cp = strchr(bprm->buf, '\n')) == NULL)
cp = bprm->buf+127;
*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_start = i_name = cp;
i_arg = 0;
for ( ; *cp && (*cp != ' ') && (*cp != '\t'); cp++) {
if (*cp == '/')
i_name = cp+1;
}
while ((*cp == ' ') || (*cp == '\t'))
*cp++ = '\0';
if (*cp)
i_arg = cp;
strcpy (interp, i_name_start);
/*
* 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.
*/
remove_arg_zero(bprm);
bprm->p = copy_strings(1, &bprm->filename, bprm->page, bprm->p, 2);
bprm->argc++;
if (i_arg) {
bprm->p = copy_strings(1, &i_arg, bprm->page, bprm->p, 2);
bprm->argc++;
}
bprm->p = copy_strings(1, &i_name, bprm->page, bprm->p, 2);
bprm->argc++;
if (!bprm->p)
return -E2BIG;
/*
* OK, now restart the process with the interpreter's dentry.
*/
dentry = open_namei(interp, 0, 0);
if (IS_ERR(dentry))
return PTR_ERR(dentry);
bprm->dentry = dentry;
retval = prepare_binprm(bprm);
if (retval < 0)
return retval;
return search_binary_handler(bprm,regs);
}
static int load_script(struct linux_binprm *bprm,struct pt_regs *regs)
{
int retval;
MOD_INC_USE_COUNT;
retval = do_load_script(bprm,regs);
MOD_DEC_USE_COUNT;
return retval;
}
struct linux_binfmt script_format = {
#ifndef MODULE
NULL, 0, load_script, NULL, NULL
#else
NULL, &__this_module, load_script, NULL, NULL
#endif
};
__initfunc(int init_script_binfmt(void))
{
return register_binfmt(&script_format);
}
#ifdef MODULE
int init_module(void)
{
return init_script_binfmt();
}
void cleanup_module( void) {
unregister_binfmt(&script_format);
}
#endif
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