security

/* Helpers for initial module or kernel cmdline parsing
   Copyright (C) 2001 Rusty Russell.

    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.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/ctype.h>

#if 0
#define DEBUGP printk
#else
#define DEBUGP(fmt, a...)
#endif

/* Protects all parameters, and incidentally kmalloced_param list. */
static DEFINE_MUTEX(param_lock);

/* This just allows us to keep track of which parameters are kmalloced. */
struct kmalloced_param {
	struct list_head list;
	char val[];
};
static LIST_HEAD(kmalloced_params);

static void *kmalloc_parameter(unsigned int size)
{
	struct kmalloced_param *p;

	p = kmalloc(sizeof(*p) + size, GFP_KERNEL);
	if (!p)
		return NULL;

	list_add(&p->list, &kmalloced_params);
	return p->val;
}

/* Does nothing if parameter wasn't kmalloced above. */
static void maybe_kfree_parameter(void *param)
{
	struct kmalloced_param *p;

	list_for_each_entry(p, &kmalloced_params, list) {
		if (p->val == param) {
			list_del(&p->list);
			kfree(p);
			break;
		}
	}
}

static char dash2underscore(char c)
{
	if (c == '-')
		return '_';
	return c;
}

bool parameqn(const char *a, const char *b, size_t n)
{
	size_t i;

	for (i = 0; i < n; i++) {
		if (dash2underscore(a[i]) != dash2underscore(b[i]))
			return false;
	}
	return true;
}

bool parameq(const char *a, const char *b)
{
	return parameqn(a, b, strlen(a)+1);
}

static int parse_one(char *param,
		     char *val,
		     const struct kernel_param *params,
		     unsigned num_params,
		     int (*handle_unknown)(char *param, char *val))
{
	unsigned int i;
	int err;

	/* Find parameter */
	for (i = 0; i < num_params; i++) {
		if (parameq(param, params[i].name)) {
			/* No one handled NULL, so do it here. */
			if (!val && params[i].ops->set != param_set_bool)
				return -EINVAL;
			DEBUGP("They are equal!  Calling %p\n",
			       params[i].ops->set);
			mutex_lock(&param_lock);
			err = params[i].ops->set(val, &params[i]);
			mutex_unlock(&param_lock);
			return err;
		}
	}

	if (handle_unknown) {
		DEBUGP("Unknown argument: calling %p\n", handle_unknown);
		return handle_unknown(param, val);
	}

	DEBUGP("Unknown argument `%s'\n", param);
	return -ENOENT;
}

/* You can use " around spaces, but can't escape ". */
/* Hyphens and underscores equivalent in parameter names. */
static char *next_arg(char *args, char **param, char **val)
{
	unsigned int i, equals = 0;
	int in_quote = 0, quoted = 0;
	char *next;

	if (*args == '"') {
		args++;
		in_quote = 1;
		quoted = 1;
	}

	for (i = 0; args[i]; i++) {
		if (isspace(args[i]) && !in_quote)
			break;
		if (equals == 0) {
			if (args[i] == '=')
				equals = i;
		}
		if (args[i] == '"')
			in_quote = !in_quote;
	}

	*param = args;
	if (!equals)
		*val = NULL;
	else {
		args[equals] = '\0';
		*val = args + equals + 1;

		/* Don't include quotes in value. */
		if (**val == '"') {
			(*val)++;
			if (args[i-1] == '"')
				args[i-1] = '\0';
		}
		if (quoted && args[i-1] == '"')
			args[i-1] = '\0';
	}

	if (args[i]) {
		args[i] = '\0';
		next = args + i + 1;
	} else
		next = args + i;

	/* Chew up trailing spaces. */
	return skip_spaces(next);
}

/* Args looks like "foo=bar,bar2 baz=fuz wiz". */
int parse_args(const char *name,
	       char *args,
	       const struct kernel_param *params,
	       unsigned num,
	       int (*unknown)(char *param, char *val))
{
	char *param, *val;

	DEBUGP("Parsing ARGS: %s\n", args);

	/* Chew leading spaces */
	args = skip_spaces(args);

	while (*args) {
		int ret;
		int irq_was_disabled;

		args = next_arg(args, &param, &val);
		irq_was_disabled = irqs_disabled();
		ret = parse_one(param, val, params, num, unknown);
		if (irq_was_disabled && !irqs_disabled()) {
			printk(KERN_WARNING "parse_args(): option '%s' enabled "
					"irq's!\n", param);
		}
		switch (ret) {
		case -ENOENT:
			printk(KERN_ERR "%s: Unknown parameter `%s'\n",
			       name, param);
			return ret;
		case -ENOSPC:
			printk(KERN_ERR
			       "%s: `%s' too large for parameter `%s'\n",
			       name, val ?: "", param);
			return ret;
		case 0:
			break;
		default:
			printk(KERN_ERR
			       "%s: `%s' invalid for parameter `%s'\n",
			       name, val ?: "", param);
			return ret;
		}
	}

	/* All parsed OK. */
	return 0;
}

/* Lazy bastard, eh? */
#define STANDARD_PARAM_DEF(name, type, format, tmptype, strtolfn)      	\
	int param_set_##name(const char *val, const struct kernel_param *kp) \
	{								\
		tmptype l;						\
		int ret;						\
Mode	Name	Size
-rw-r--r--	Kconfig	5819	log stats plain blame
-rw-r--r--	Makefile	1029	log stats plain blame
d---------	apparmor	757	log stats plain
-rw-r--r--	capability.c	24893	log stats plain blame
-rw-r--r--	commoncap.c	28824	log stats plain blame
-rw-r--r--	device_cgroup.c	18299	log stats plain blame
-rw-r--r--	inode.c	6849	log stats plain blame
d---------	integrity	332	log stats plain
d---------	keys	679	log stats plain
-rw-r--r--	lsm_audit.c	9557	log stats plain blame
-rw-r--r--	min_addr.c	1345	log stats plain blame
-rw-r--r--	security.c	36624	log stats plain blame
d---------	selinux	572	log stats plain
d---------	smack	224	log stats plain
d---------	tomoyo	729	log stats plain
d---------	yama	109	log stats plain