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/*
* linux/fs/binfmt_em86.c
*
* Based on linux/fs/binfmt_script.c
* Copyright (C) 1996 Martin von Löwis
* original #!-checking implemented by tytso.
*
* em86 changes Copyright (C) 1997 Jim Paradis
*/
#include <linux/module.h>
#include <linux/string.h>
#include <linux/stat.h>
#include <linux/malloc.h>
#include <linux/binfmts.h>
#include <linux/elf.h>
#include <linux/init.h>
#define EM86_INTERP "/usr/bin/em86"
#define EM86_I_NAME "em86"
static int do_load_em86(struct linux_binprm *bprm,struct pt_regs *regs)
{
char *interp, *i_name, *i_arg;
struct dentry * dentry;
int retval;
struct elfhdr elf_ex;
/* Make sure this is a Linux/Intel ELF executable... */
elf_ex = *((struct elfhdr *)bprm->buf);
if (elf_ex.e_ident[0] != 0x7f ||
strncmp(&elf_ex.e_ident[1], "ELF",3) != 0) {
return -ENOEXEC;
}
/* First of all, some simple consistency checks */
if ((elf_ex.e_type != ET_EXEC &&
elf_ex.e_type != ET_DYN) ||
(!((elf_ex.e_machine == EM_386) || (elf_ex.e_machine == EM_486))) ||
(!bprm->dentry->d_inode->i_op || !bprm->dentry->d_inode->i_op->default_file_ops ||
!bprm->dentry->d_inode->i_op->default_file_ops->mmap)){
return -ENOEXEC;
}
bprm->sh_bang++; /* Well, the bang-shell is implicit... */
dput(bprm->dentry);
bprm->dentry = NULL;
/* Unlike in the script case, we don't have to do any hairy
* parsing to find our interpreter... it's hardcoded!
*/
interp = EM86_INTERP;
i_name = EM86_I_NAME;
i_arg = NULL; /* We reserve the right to add an arg later */
/*
* Splice in (1) the interpreter's name for argv[0]
* (2) (optional) argument to interpreter
* (3) filename of emulated file (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 inode.
* Note that we use open_namei() as the name is now in kernel
* space, and we don't need to copy it.
*/
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_em86(struct linux_binprm *bprm,struct pt_regs *regs)
{
int retval;
MOD_INC_USE_COUNT;
retval = do_load_em86(bprm,regs);
MOD_DEC_USE_COUNT;
return retval;
}
struct linux_binfmt em86_format = {
#ifndef MODULE
NULL, 0, load_em86, NULL, NULL
#else
NULL, &__this_module, load_em86, NULL, NULL
#endif
};
int __init init_em86_binfmt(void)
{
return register_binfmt(&em86_format);
}
#ifdef MODULE
int init_module(void)
{
return init_em86_binfmt();
}
void cleanup_module( void) {
unregister_binfmt(&em86_format);
}
#endif
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