[net-next-2.6.git] / security / apparmor / resource.c

/*
 * AppArmor security module
 *
 * This file contains AppArmor resource mediation and attachment
 *
 * Copyright (C) 1998-2008 Novell/SUSE
 * Copyright 2009-2010 Canonical Ltd.
 *
 * 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, version 2 of the
 * License.
 */

#include <linux/audit.h>

#include "include/audit.h"
#include "include/resource.h"
#include "include/policy.h"

/*
 * Table of rlimit names: we generate it from resource.h.
 */
#include "rlim_names.h"

/* audit callback for resource specific fields */
static void audit_cb(struct audit_buffer *ab, void *va)
{
	struct common_audit_data *sa = va;

	audit_log_format(ab, " rlimit=%s value=%lu",
			 rlim_names[sa->aad.rlim.rlim], sa->aad.rlim.max);
}

/**
 * audit_resource - audit setting resource limit
 * @profile: profile being enforced  (NOT NULL)
 * @resoure: rlimit being auditing
 * @value: value being set
 * @error: error value
 *
 * Returns: 0 or sa->error else other error code on failure
 */
static int audit_resource(struct aa_profile *profile, unsigned int resource,
			  unsigned long value, int error)
{
	struct common_audit_data sa;

	COMMON_AUDIT_DATA_INIT(&sa, NONE);
	sa.aad.op = OP_SETRLIMIT,
	sa.aad.rlim.rlim = resource;
	sa.aad.rlim.max = value;
	sa.aad.error = error;
	return aa_audit(AUDIT_APPARMOR_AUTO, profile, GFP_KERNEL, &sa,
			audit_cb);
}

/**
 * aa_map_resouce - map compiled policy resource to internal #
 * @resource: flattened policy resource number
 *
 * Returns: resource # for the current architecture.
 *
 * rlimit resource can vary based on architecture, map the compiled policy
 * resource # to the internal representation for the architecture.
 */
int aa_map_resource(int resource)
{
	return rlim_map[resource];
}

/**
 * aa_task_setrlimit - test permission to set an rlimit
 * @profile - profile confining the task  (NOT NULL)
 * @task - task the resource is being set on
 * @resource - the resource being set
 * @new_rlim - the new resource limit  (NOT NULL)
 *
 * Control raising the processes hard limit.
 *
 * Returns: 0 or error code if setting resource failed
 */
int aa_task_setrlimit(struct aa_profile *profile, struct task_struct *task,
		      unsigned int resource, struct rlimit *new_rlim)
{
	int error = 0;

	/* TODO: extend resource control to handle other (non current)
	 * processes.  AppArmor rules currently have the implicit assumption
	 * that the task is setting the resource of the current process
	 */
	if ((task != current->group_leader) ||
	    (profile->rlimits.mask & (1 << resource) &&
	     new_rlim->rlim_max > profile->rlimits.limits[resource].rlim_max))
		error = -EACCES;

	return audit_resource(profile, resource, new_rlim->rlim_max, error);
}

/**
 * __aa_transition_rlimits - apply new profile rlimits
 * @old: old profile on task  (NOT NULL)
 * @new: new profile with rlimits to apply  (NOT NULL)
 */
void __aa_transition_rlimits(struct aa_profile *old, struct aa_profile *new)
{
	unsigned int mask = 0;
	struct rlimit *rlim, *initrlim;
	int i;

	/* for any rlimits the profile controlled reset the soft limit
	 * to the less of the tasks hard limit and the init tasks soft limit
	 */
	if (old->rlimits.mask) {
		for (i = 0, mask = 1; i < RLIM_NLIMITS; i++, mask <<= 1) {
			if (old->rlimits.mask & mask) {
				rlim = current->signal->rlim + i;
				initrlim = init_task.signal->rlim + i;
				rlim->rlim_cur = min(rlim->rlim_max,
						     initrlim->rlim_cur);
			}
		}
	}

	/* set any new hard limits as dictated by the new profile */
	if (!new->rlimits.mask)
		return;
	for (i = 0, mask = 1; i < RLIM_NLIMITS; i++, mask <<= 1) {
		if (!(new->rlimits.mask & mask))
			continue;

		rlim = current->signal->rlim + i;
		rlim->rlim_max = min(rlim->rlim_max,
				     new->rlimits.limits[i].rlim_max);
		/* soft limit should not exceed hard limit */
		rlim->rlim_cur = min(rlim->rlim_cur, rlim->rlim_max);
	}
}
Commit	Line	Data
0ed3b28a JJ	1	/*
	2	* AppArmor security module
	3	*
	4	* This file contains AppArmor resource mediation and attachment
	5	*
	6	* Copyright (C) 1998-2008 Novell/SUSE
	7	* Copyright 2009-2010 Canonical Ltd.
	8	*
	9	* This program is free software; you can redistribute it and/or
	10	* modify it under the terms of the GNU General Public License as
	11	* published by the Free Software Foundation, version 2 of the
	12	* License.
	13	*/
	14
	15	#include <linux/audit.h>
	16
	17	#include "include/audit.h"
	18	#include "include/resource.h"
	19	#include "include/policy.h"
	20
	21	/*
	22	* Table of rlimit names: we generate it from resource.h.
	23	*/
	24	#include "rlim_names.h"
	25
	26	/* audit callback for resource specific fields */
	27	static void audit_cb(struct audit_buffer ab, void va)
	28	{
	29	struct common_audit_data *sa = va;
	30
	31	audit_log_format(ab, " rlimit=%s value=%lu",
	32	rlim_names[sa->aad.rlim.rlim], sa->aad.rlim.max);
	33	}
	34
	35	/**
	36	* audit_resource - audit setting resource limit
	37	* @profile: profile being enforced (NOT NULL)
	38	* @resoure: rlimit being auditing
	39	* @value: value being set
	40	* @error: error value
	41	*
	42	* Returns: 0 or sa->error else other error code on failure
	43	*/
	44	static int audit_resource(struct aa_profile *profile, unsigned int resource,
	45	unsigned long value, int error)
	46	{
	47	struct common_audit_data sa;
	48
	49	COMMON_AUDIT_DATA_INIT(&sa, NONE);
	50	sa.aad.op = OP_SETRLIMIT,
	51	sa.aad.rlim.rlim = resource;
	52	sa.aad.rlim.max = value;
	53	sa.aad.error = error;
	54	return aa_audit(AUDIT_APPARMOR_AUTO, profile, GFP_KERNEL, &sa,
	55	audit_cb);
	56	}
	57
	58	/**
	59	* aa_map_resouce - map compiled policy resource to internal #
	60	* @resource: flattened policy resource number
	61	*
	62	* Returns: resource # for the current architecture.
	63	*
	64	* rlimit resource can vary based on architecture, map the compiled policy
65	* resource # to the internal representation for the architecture.
66	*/
67	int aa_map_resource(int resource)
68	{
69	return rlim_map[resource];
70	}
71
72	/**
73	* aa_task_setrlimit - test permission to set an rlimit
74	* @profile - profile confining the task (NOT NULL)
3a2dc838	75	* @task - task the resource is being set on
0ed3b28a JJ	76	* @resource - the resource being set
	77	* @new_rlim - the new resource limit (NOT NULL)
	78	*
	79	* Control raising the processes hard limit.
	80	*
	81	* Returns: 0 or error code if setting resource failed
	82	*/
3a2dc838 JJ	83	int aa_task_setrlimit(struct aa_profile profile, struct task_struct task,
3a2dc838 JJ	84	unsigned int resource, struct rlimit *new_rlim)
0ed3b28a JJ	85	{
	86	int error = 0;
	87
3a2dc838 JJ	88	/* TODO: extend resource control to handle other (non current)
	89	* processes. AppArmor rules currently have the implicit assumption
	90	* that the task is setting the resource of the current process
	91	*/
	92	if ((task != current->group_leader) \|\|
	93	(profile->rlimits.mask & (1 << resource) &&
	94	new_rlim->rlim_max > profile->rlimits.limits[resource].rlim_max))
	95	error = -EACCES;
0ed3b28a	96
3a2dc838	97	return audit_resource(profile, resource, new_rlim->rlim_max, error);
0ed3b28a JJ	98	}
	99
	100	/**
	101	* __aa_transition_rlimits - apply new profile rlimits
	102	* @old: old profile on task (NOT NULL)
	103	* @new: new profile with rlimits to apply (NOT NULL)
	104	*/
	105	void __aa_transition_rlimits(struct aa_profile old, struct aa_profile new)
	106	{
	107	unsigned int mask = 0;
	108	struct rlimit rlim, initrlim;
	109	int i;
	110
	111	/* for any rlimits the profile controlled reset the soft limit
	112	* to the less of the tasks hard limit and the init tasks soft limit
	113	*/
	114	if (old->rlimits.mask) {
	115	for (i = 0, mask = 1; i < RLIM_NLIMITS; i++, mask <<= 1) {
	116	if (old->rlimits.mask & mask) {
	117	rlim = current->signal->rlim + i;
	118	initrlim = init_task.signal->rlim + i;
	119	rlim->rlim_cur = min(rlim->rlim_max,
	120	initrlim->rlim_cur);
	121	}
	122	}
	123	}
	124
	125	/* set any new hard limits as dictated by the new profile */
	126	if (!new->rlimits.mask)
	127	return;
	128	for (i = 0, mask = 1; i < RLIM_NLIMITS; i++, mask <<= 1) {
	129	if (!(new->rlimits.mask & mask))
	130	continue;
	131
	132	rlim = current->signal->rlim + i;
	133	rlim->rlim_max = min(rlim->rlim_max,
	134	new->rlimits.limits[i].rlim_max);
	135	/* soft limit should not exceed hard limit */
	136	rlim->rlim_cur = min(rlim->rlim_cur, rlim->rlim_max);
	137	}
	138	}