[mirror_ubuntu-bionic-kernel.git] / security / apparmor / include / file.h

/*
 * AppArmor security module
 *
 * This file contains AppArmor file mediation function definitions.
 *
 * 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.
 */

#ifndef __AA_FILE_H
#define __AA_FILE_H

#include <linux/spinlock.h>

#include "domain.h"
#include "match.h"
#include "perms.h"

struct aa_profile;
struct path;

#define mask_mode_t(X) (X & (MAY_EXEC | MAY_WRITE | MAY_READ | MAY_APPEND))

#define AA_AUDIT_FILE_MASK	(MAY_READ | MAY_WRITE | MAY_EXEC | MAY_APPEND |\
				 AA_MAY_CREATE | AA_MAY_DELETE |	\
				 AA_MAY_GETATTR | AA_MAY_SETATTR | \
				 AA_MAY_CHMOD | AA_MAY_CHOWN | AA_MAY_LOCK | \
				 AA_EXEC_MMAP | AA_MAY_LINK)

#define file_ctx(X) apparmor_file(X)

/* struct aa_file_ctx - the AppArmor context the file was opened in
 * @lock: lock to update the ctx
 * @label: label currently cached on the ctx
 * @perms: the permission the file was opened with
 */
struct aa_file_ctx {
	spinlock_t lock;
	struct aa_label __rcu *label;
	u32 allow;
};

/**
 * aa_alloc_file_ctx - allocate file_ctx
 * @label: initial label of task creating the file
 * @gfp: gfp flags for allocation
 *
 * Returns: file_ctx or NULL on failure
 */
static inline struct aa_file_ctx *aa_alloc_file_ctx(struct aa_label *label,
						    gfp_t gfp)
{
	struct aa_file_ctx *ctx;

	ctx = kzalloc(sizeof(struct aa_file_ctx), gfp);
	if (ctx) {
		spin_lock_init(&ctx->lock);
		rcu_assign_pointer(ctx->label, aa_get_label(label));
	}
	return ctx;
}

/**
 * aa_free_file_ctx - free a file_ctx
 * @ctx: file_ctx to free  (MAYBE_NULL)
 */
static inline void aa_free_file_ctx(struct aa_file_ctx *ctx)
{
	if (ctx) {
		aa_put_label(rcu_access_pointer(ctx->label));
		kzfree(ctx);
	}
}

static inline struct aa_label *aa_get_file_label(struct aa_file_ctx *ctx)
{
	return aa_get_label_rcu(&ctx->label);
}

/*
 * The xindex is broken into 3 parts
 * - index - an index into either the exec name table or the variable table
 * - exec type - which determines how the executable name and index are used
 * - flags - which modify how the destination name is applied
 */
#define AA_X_INDEX_MASK		0x03ff

#define AA_X_TYPE_MASK		0x0c00
#define AA_X_TYPE_SHIFT		10
#define AA_X_NONE		0x0000
#define AA_X_NAME		0x0400	/* use executable name px */
#define AA_X_TABLE		0x0800	/* use a specified name ->n# */

#define AA_X_UNSAFE		0x1000
#define AA_X_CHILD		0x2000	/* make >AA_X_NONE apply to children */
#define AA_X_INHERIT		0x4000
#define AA_X_UNCONFINED		0x8000

/* need to make conditional which ones are being set */
struct path_cond {
	kuid_t uid;
	umode_t mode;
};

#define COMBINED_PERM_MASK(X) ((X).allow | (X).audit | (X).quiet | (X).kill)

/* FIXME: split perms from dfa and match this to description
 *        also add delegation info.
 */
static inline u16 dfa_map_xindex(u16 mask)
{
	u16 old_index = (mask >> 10) & 0xf;
	u16 index = 0;

	if (mask & 0x100)
		index |= AA_X_UNSAFE;
	if (mask & 0x200)
		index |= AA_X_INHERIT;
	if (mask & 0x80)
		index |= AA_X_UNCONFINED;

	if (old_index == 1) {
		index |= AA_X_UNCONFINED;
	} else if (old_index == 2) {
		index |= AA_X_NAME;
	} else if (old_index == 3) {
		index |= AA_X_NAME | AA_X_CHILD;
	} else if (old_index) {
		index |= AA_X_TABLE;
		index |= old_index - 4;
	}

	return index;
}

/*
 * map old dfa inline permissions to new format
 */
#define dfa_user_allow(dfa, state) (((ACCEPT_TABLE(dfa)[state]) & 0x7f) | \
				    ((ACCEPT_TABLE(dfa)[state]) & 0x80000000))
#define dfa_user_audit(dfa, state) ((ACCEPT_TABLE2(dfa)[state]) & 0x7f)
#define dfa_user_quiet(dfa, state) (((ACCEPT_TABLE2(dfa)[state]) >> 7) & 0x7f)
#define dfa_user_xindex(dfa, state) \
	(dfa_map_xindex(ACCEPT_TABLE(dfa)[state] & 0x3fff))

#define dfa_other_allow(dfa, state) ((((ACCEPT_TABLE(dfa)[state]) >> 14) & \
				      0x7f) |				\
				     ((ACCEPT_TABLE(dfa)[state]) & 0x80000000))
#define dfa_other_audit(dfa, state) (((ACCEPT_TABLE2(dfa)[state]) >> 14) & 0x7f)
#define dfa_other_quiet(dfa, state) \
	((((ACCEPT_TABLE2(dfa)[state]) >> 7) >> 14) & 0x7f)
#define dfa_other_xindex(dfa, state) \
	dfa_map_xindex((ACCEPT_TABLE(dfa)[state] >> 14) & 0x3fff)

int aa_audit_file(struct aa_profile *profile, struct aa_perms *perms,
		  const char *op, u32 request, const char *name,
		  const char *target, struct aa_label *tlabel, kuid_t ouid,
		  const char *info, int error);

/**
 * struct aa_file_rules - components used for file rule permissions
 * @dfa: dfa to match path names and conditionals against
 * @perms: permission table indexed by the matched state accept entry of @dfa
 * @trans: transition table for indexed by named x transitions
 *
 * File permission are determined by matching a path against @dfa and then
 * then using the value of the accept entry for the matching state as
 * an index into @perms.  If a named exec transition is required it is
 * looked up in the transition table.
 */
struct aa_file_rules {
	unsigned int start;
	struct aa_dfa *dfa;
	/* struct perms perms; */
	struct aa_domain trans;
	/* TODO: add delegate table */
};

struct aa_perms aa_compute_fperms(struct aa_dfa *dfa, unsigned int state,
				    struct path_cond *cond);
unsigned int aa_str_perms(struct aa_dfa *dfa, unsigned int start,
			  const char *name, struct path_cond *cond,
			  struct aa_perms *perms);

int __aa_path_perm(const char *op, struct aa_profile *profile,
		   const char *name, u32 request, struct path_cond *cond,
		   int flags, struct aa_perms *perms);
int aa_path_perm(const char *op, struct aa_label *label,
		 const struct path *path, int flags, u32 request,
		 struct path_cond *cond);

int aa_path_link(struct aa_label *label, struct dentry *old_dentry,
		 const struct path *new_dir, struct dentry *new_dentry);

int aa_file_perm(const char *op, struct aa_label *label, struct file *file,
		 u32 request);

void aa_inherit_files(const struct cred *cred, struct files_struct *files);

static inline void aa_free_file_rules(struct aa_file_rules *rules)
{
	aa_put_dfa(rules->dfa);
	aa_free_domain_entries(&rules->trans);
}

/**
 * aa_map_file_perms - map file flags to AppArmor permissions
 * @file: open file to map flags to AppArmor permissions
 *
 * Returns: apparmor permission set for the file
 */
static inline u32 aa_map_file_to_perms(struct file *file)
{
	int flags = file->f_flags;
	u32 perms = 0;

	if (file->f_mode & FMODE_WRITE)
		perms |= MAY_WRITE;
	if (file->f_mode & FMODE_READ)
		perms |= MAY_READ;

	if ((flags & O_APPEND) && (perms & MAY_WRITE))
		perms = (perms & ~MAY_WRITE) | MAY_APPEND;
	/* trunc implies write permission */
	if (flags & O_TRUNC)
		perms |= MAY_WRITE;
	if (flags & O_CREAT)
		perms |= AA_MAY_CREATE;

	return perms;
}

#endif /* __AA_FILE_H */
Commit	Line	Data
	1	/*
	2	* AppArmor security module
	3	*
	4	* This file contains AppArmor file mediation function definitions.
	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	#ifndef __AA_FILE_H
	16	#define __AA_FILE_H
	17
	18	#include <linux/spinlock.h>
	19
	20	#include "domain.h"
	21	#include "match.h"
	22	#include "perms.h"
	23
	24	struct aa_profile;
	25	struct path;
	26
	27	#define mask_mode_t(X) (X & (MAY_EXEC \| MAY_WRITE \| MAY_READ \| MAY_APPEND))
	28
	29	#define AA_AUDIT_FILE_MASK (MAY_READ \| MAY_WRITE \| MAY_EXEC \| MAY_APPEND \|\
	30	AA_MAY_CREATE \| AA_MAY_DELETE \| \
	31	AA_MAY_GETATTR \| AA_MAY_SETATTR \| \
	32	AA_MAY_CHMOD \| AA_MAY_CHOWN \| AA_MAY_LOCK \| \
	33	AA_EXEC_MMAP \| AA_MAY_LINK)
	34
	35	#define file_ctx(X) apparmor_file(X)
	36
	37	/* struct aa_file_ctx - the AppArmor context the file was opened in
	38	* @lock: lock to update the ctx
	39	* @label: label currently cached on the ctx
	40	* @perms: the permission the file was opened with
	41	*/
	42	struct aa_file_ctx {
	43	spinlock_t lock;
	44	struct aa_label __rcu *label;
	45	u32 allow;
	46	};
	47
	48	/**
	49	* aa_alloc_file_ctx - allocate file_ctx
	50	* @label: initial label of task creating the file
	51	* @gfp: gfp flags for allocation
	52	*
	53	* Returns: file_ctx or NULL on failure
	54	*/
	55	static inline struct aa_file_ctx aa_alloc_file_ctx(struct aa_label label,
	56	gfp_t gfp)
	57	{
	58	struct aa_file_ctx *ctx;
	59
	60	ctx = kzalloc(sizeof(struct aa_file_ctx), gfp);
	61	if (ctx) {
	62	spin_lock_init(&ctx->lock);
	63	rcu_assign_pointer(ctx->label, aa_get_label(label));
	64	}
	65	return ctx;
	66	}
	67
	68	/**
	69	* aa_free_file_ctx - free a file_ctx
	70	* @ctx: file_ctx to free (MAYBE_NULL)
	71	*/
	72	static inline void aa_free_file_ctx(struct aa_file_ctx *ctx)
	73	{
	74	if (ctx) {
	75	aa_put_label(rcu_access_pointer(ctx->label));
	76	kzfree(ctx);
	77	}
	78	}
	79
	80	static inline struct aa_label aa_get_file_label(struct aa_file_ctx ctx)
	81	{
	82	return aa_get_label_rcu(&ctx->label);
	83	}
	84
	85	/*
	86	* The xindex is broken into 3 parts
	87	* - index - an index into either the exec name table or the variable table
	88	* - exec type - which determines how the executable name and index are used
	89	* - flags - which modify how the destination name is applied
	90	*/
	91	#define AA_X_INDEX_MASK 0x03ff
	92
	93	#define AA_X_TYPE_MASK 0x0c00
	94	#define AA_X_TYPE_SHIFT 10
	95	#define AA_X_NONE 0x0000
	96	#define AA_X_NAME 0x0400 /* use executable name px */
	97	#define AA_X_TABLE 0x0800 /* use a specified name ->n# */
	98
	99	#define AA_X_UNSAFE 0x1000
	100	#define AA_X_CHILD 0x2000 /* make >AA_X_NONE apply to children */
	101	#define AA_X_INHERIT 0x4000
	102	#define AA_X_UNCONFINED 0x8000
	103
	104	/* need to make conditional which ones are being set */
	105	struct path_cond {
	106	kuid_t uid;
	107	umode_t mode;
	108	};
	109
	110	#define COMBINED_PERM_MASK(X) ((X).allow \| (X).audit \| (X).quiet \| (X).kill)
	111
	112	/* FIXME: split perms from dfa and match this to description
	113	* also add delegation info.
	114	*/
	115	static inline u16 dfa_map_xindex(u16 mask)
	116	{
	117	u16 old_index = (mask >> 10) & 0xf;
	118	u16 index = 0;
	119
	120	if (mask & 0x100)
	121	index \|= AA_X_UNSAFE;
	122	if (mask & 0x200)
	123	index \|= AA_X_INHERIT;
	124	if (mask & 0x80)
	125	index \|= AA_X_UNCONFINED;
	126
	127	if (old_index == 1) {
	128	index \|= AA_X_UNCONFINED;
	129	} else if (old_index == 2) {
	130	index \|= AA_X_NAME;
	131	} else if (old_index == 3) {
	132	index \|= AA_X_NAME \| AA_X_CHILD;
	133	} else if (old_index) {
	134	index \|= AA_X_TABLE;
	135	index \|= old_index - 4;
	136	}
	137
	138	return index;
	139	}
	140
	141	/*
	142	* map old dfa inline permissions to new format
	143	*/
	144	#define dfa_user_allow(dfa, state) (((ACCEPT_TABLE(dfa)[state]) & 0x7f) \| \
	145	((ACCEPT_TABLE(dfa)[state]) & 0x80000000))
	146	#define dfa_user_audit(dfa, state) ((ACCEPT_TABLE2(dfa)[state]) & 0x7f)
	147	#define dfa_user_quiet(dfa, state) (((ACCEPT_TABLE2(dfa)[state]) >> 7) & 0x7f)
	148	#define dfa_user_xindex(dfa, state) \
	149	(dfa_map_xindex(ACCEPT_TABLE(dfa)[state] & 0x3fff))
	150
	151	#define dfa_other_allow(dfa, state) ((((ACCEPT_TABLE(dfa)[state]) >> 14) & \
	152	0x7f) \| \
	153	((ACCEPT_TABLE(dfa)[state]) & 0x80000000))
	154	#define dfa_other_audit(dfa, state) (((ACCEPT_TABLE2(dfa)[state]) >> 14) & 0x7f)
	155	#define dfa_other_quiet(dfa, state) \
	156	((((ACCEPT_TABLE2(dfa)[state]) >> 7) >> 14) & 0x7f)
	157	#define dfa_other_xindex(dfa, state) \
	158	dfa_map_xindex((ACCEPT_TABLE(dfa)[state] >> 14) & 0x3fff)
	159
	160	int aa_audit_file(struct aa_profile profile, struct aa_perms perms,
	161	const char op, u32 request, const char name,
	162	const char target, struct aa_label tlabel, kuid_t ouid,
	163	const char *info, int error);
	164
	165	/**
	166	* struct aa_file_rules - components used for file rule permissions
	167	* @dfa: dfa to match path names and conditionals against
	168	* @perms: permission table indexed by the matched state accept entry of @dfa
	169	* @trans: transition table for indexed by named x transitions
	170	*
	171	* File permission are determined by matching a path against @dfa and then
	172	* then using the value of the accept entry for the matching state as
	173	* an index into @perms. If a named exec transition is required it is
	174	* looked up in the transition table.
	175	*/
	176	struct aa_file_rules {
	177	unsigned int start;
	178	struct aa_dfa *dfa;
	179	/* struct perms perms; */
	180	struct aa_domain trans;
	181	/* TODO: add delegate table */
	182	};
	183
	184	struct aa_perms aa_compute_fperms(struct aa_dfa *dfa, unsigned int state,
	185	struct path_cond *cond);
	186	unsigned int aa_str_perms(struct aa_dfa *dfa, unsigned int start,
	187	const char name, struct path_cond cond,
	188	struct aa_perms *perms);
	189
	190	int __aa_path_perm(const char op, struct aa_profile profile,
	191	const char name, u32 request, struct path_cond cond,
	192	int flags, struct aa_perms *perms);
	193	int aa_path_perm(const char op, struct aa_label label,
	194	const struct path *path, int flags, u32 request,
	195	struct path_cond *cond);
	196
	197	int aa_path_link(struct aa_label label, struct dentry old_dentry,
	198	const struct path new_dir, struct dentry new_dentry);
	199
	200	int aa_file_perm(const char op, struct aa_label label, struct file *file,
	201	u32 request);
	202
	203	void aa_inherit_files(const struct cred cred, struct files_struct files);
	204
	205	static inline void aa_free_file_rules(struct aa_file_rules *rules)
	206	{
	207	aa_put_dfa(rules->dfa);
	208	aa_free_domain_entries(&rules->trans);
	209	}
	210
	211	/**
	212	* aa_map_file_perms - map file flags to AppArmor permissions
	213	* @file: open file to map flags to AppArmor permissions
	214	*
	215	* Returns: apparmor permission set for the file
	216	*/
	217	static inline u32 aa_map_file_to_perms(struct file *file)
	218	{
	219	int flags = file->f_flags;
	220	u32 perms = 0;
	221
	222	if (file->f_mode & FMODE_WRITE)
	223	perms \|= MAY_WRITE;
	224	if (file->f_mode & FMODE_READ)
	225	perms \|= MAY_READ;
	226
	227	if ((flags & O_APPEND) && (perms & MAY_WRITE))
	228	perms = (perms & ~MAY_WRITE) \| MAY_APPEND;
	229	/* trunc implies write permission */
	230	if (flags & O_TRUNC)
	231	perms \|= MAY_WRITE;
	232	if (flags & O_CREAT)
	233	perms \|= AA_MAY_CREATE;
	234
	235	return perms;
	236	}
	237
	238	#endif /* __AA_FILE_H */