2 * linux/fs/binfmt_script.c
4 * Copyright (C) 1996 Martin von Löwis
5 * original #!-checking implemented by tytso.
8 #include <linux/module.h>
9 #include <linux/string.h>
10 #include <linux/stat.h>
11 #include <linux/slab.h>
12 #include <linux/binfmts.h>
13 #include <linux/init.h>
14 #include <linux/file.h>
15 #include <linux/smp_lock.h>
17 static int load_script(struct linux_binprm *bprm,struct pt_regs *regs)
19 char *cp, *i_name, *i_arg;
21 char interp[BINPRM_BUF_SIZE];
24 if ((bprm->buf[0] != '#') || (bprm->buf[1] != '!') || (bprm->sh_bang))
27 * This section does the #! interpretation.
28 * Sorta complicated, but hopefully it will work. -TYT
32 allow_write_access(bprm->file);
36 bprm->buf[BINPRM_BUF_SIZE - 1] = '\0';
37 if ((cp = strchr(bprm->buf, '\n')) == NULL)
38 cp = bprm->buf+BINPRM_BUF_SIZE-1;
40 while (cp > bprm->buf) {
42 if ((*cp == ' ') || (*cp == '\t'))
47 for (cp = bprm->buf+2; (*cp == ' ') || (*cp == '\t'); cp++);
49 return -ENOEXEC; /* No interpreter name found */
52 for ( ; *cp && (*cp != ' ') && (*cp != '\t'); cp++)
54 while ((*cp == ' ') || (*cp == '\t'))
58 strcpy (interp, i_name);
60 * OK, we've parsed out the interpreter name and
61 * (optional) argument.
62 * Splice in (1) the interpreter's name for argv[0]
63 * (2) (optional) argument to interpreter
64 * (3) filename of shell script (replace argv[0])
66 * This is done in reverse order, because of how the
67 * user environment and arguments are stored.
69 remove_arg_zero(bprm);
70 retval = copy_strings_kernel(1, &bprm->filename, bprm);
71 if (retval < 0) return retval;
74 retval = copy_strings_kernel(1, &i_arg, bprm);
75 if (retval < 0) return retval;
78 retval = copy_strings_kernel(1, &i_name, bprm);
79 if (retval) return retval;
82 * OK, now restart the process with the interpreter's dentry.
84 file = open_exec(interp);
89 retval = prepare_binprm(bprm);
92 return search_binary_handler(bprm,regs);
95 struct linux_binfmt script_format = {
96 NULL, THIS_MODULE, load_script, NULL, NULL, 0
99 static int __init init_script_binfmt(void)
101 return register_binfmt(&script_format);
104 static void __exit exit_script_binfmt(void)
106 unregister_binfmt(&script_format);
109 module_init(init_script_binfmt)
110 module_exit(exit_script_binfmt)
111 MODULE_LICENSE("GPL");