/*
* Security plug functions
*
* Copyright (C) 2001 WireX Communications, Inc <chris@wirex.com>
* Copyright (C) 2001-2002 Greg Kroah-Hartman <greg@kroah.com>
* Copyright (C) 2001 Networks Associates Technology, Inc <ssmalley@nai.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*/
#include <linux/capability.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/security.h>
#include <linux/ima.h>
/* Boot-time LSM user choice */
static __initdata char chosen_lsm[SECURITY_NAME_MAX + 1] =
CONFIG_DEFAULT_SECURITY;
/* things that live in capability.c */
extern void __init security_fixup_ops(struct security_operations *ops);
static struct security_operations *security_ops;
static struct security_operations default_security_ops = {
.name = "default",
};
static inline int __init verify(struct security_operations *ops)
{
/* verify the security_operations structure exists */
if (!ops)
return -EINVAL;
security_fixup_ops(ops);
return 0;
}
static void __init do_security_initcalls(void)
{
initcall_t *call;
call = __security_initcall_start;
while (call < __security_initcall_end) {
(*call) ();
call++;
}
}
/**
* security_init - initializes the security framework
*
* This should be called early in the kernel initialization sequence.
*/
int __init security_init(void)
{
printk(KERN_INFO "Security Framework initialized\n");
security_fixup_ops(&default_security_ops);
security_ops = &default_security_ops;
do_security_initcalls();
return 0;
}
void reset_security_ops(void)
{
security_ops = &default_security_ops;
}
/* Save user chosen LSM */
static int __init choose_lsm(char *str)
{
strncpy(chosen_lsm, str, SECURITY_NAME_MAX);
return 1;
}
__setup("security=", choose_lsm);
/**
* security_module_enable - Load given security module on boot ?
* @ops: a pointer to the struct security_operations that is to be checked.
*
* Each LSM must pass this method before registering its own operations
* to avoid security registration races. This method may also be used
* to check if your LSM is currently loaded during kernel initialization.
*
* Return true if:
* -The passed LSM is the one chosen by user at boot time,
* -or the passed LSM is configured as the default and the user did not
* choose an alternate LSM at boot time.
* Otherwise, return false.
*/
int __init security_module_enable(struct security_operations *ops)
{
return !strcmp(ops->name, chosen_lsm);
}
/**
* register_security - registers a security framework with the kernel
* @ops: a pointer to the struct security_options that is to be registered
*
* This function allows a security module to register itself with the
* kernel security subsystem. Some rudimentary checking is done on the @ops
* value passed to this function. You'll need to check first if your LSM
* is allowed to register its @ops by calling security_module_enable(@ops).
*
* If there is already a security module registered with the kernel,
* an error will be returned. Otherwise %0 is returned on success.
*/
int __init register_security(struct security_operations *ops)
{
if (verify(ops)) {
pr