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

struct aa_profile;
struct path;


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

/* struct aa_file_ctx - the AppArmor context the file was opened in
 * @perms: the permission the file was opened with
 *
 * The file_ctx could currently be directly stored in file->f_security
 * as the profile reference is now stored in the f_cred.  However the
 * ctx struct will expand in the future so we keep the struct.
 */
struct aa_file_ctx {
	u16 allow;
};

/**
 * aa_alloc_file_context - allocate file_ctx
 * @gfp: gfp flags for allocation
 *
 * Returns: file_ctx or NULL on failure
 */
static inline struct aa_file_ctx *aa_alloc_file_context(gfp_t gfp)
{
	return kzalloc(sizeof(struct aa_file_ctx), gfp);
}

/**
 * aa_free_file_context - free a file_ctx
 * @ctx: file_ctx to free  (MAYBE_NULL)
 */
static inline void aa_free_file_context(struct aa_file_ctx *ctx)
{
	if (ctx)
		kzfree(ctx);
}

/*
 * 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

/* AA_SECURE_X_NEEDED - is passed in the bprm->unsafe field */
#define AA_SECURE_X_NEEDED	0x8000

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

/* struct file_perms - file permission
 * @allow: mask of permissions that are allowed
 * @audit: mask of permissions to force an audit message for
 * @quiet: mask of permissions to quiet audit messages for
 * @kill: mask of permissions that when matched will kill the task
 * @xindex: exec transition index if @allow contains MAY_EXEC
 *
 * The @audit and @queit mask should be mutually exclusive.
 */
struct file_perms {
	u32 allow;
	u32 audit;
	u32 quiet;
	u32 kill;
	u16 xindex;
};

extern struct file_perms nullperms;

#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 file_perms *perms,
		  const char *op, u32 request, const char *name,
		  const char *target, 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 */
};

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

int aa_path_perm(const char *op, struct aa_profile *profile,
		 const struct path *path, int flags, u32 request,
		 struct path_cond *cond);

int aa_path_link(struct aa_profile *profile, struct dentry *old_dentry,
		 const struct path *new_dir, struct dentry *new_dentry);

int aa_file_perm(const char *op, struct aa_profile *profile, struct file *file,
		 u32 request);

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
6380bd8d JJ	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
6380bd8d JJ	18	#include "domain.h"
6380bd8d JJ	19	#include "match.h"
fc7e0b26	20	#include "perms.h"
6380bd8d JJ	21
6380bd8d JJ	22	struct aa_profile;
37721e1b	23	struct path;
6380bd8d	24
6380bd8d JJ	25
	26	#define AA_AUDIT_FILE_MASK (MAY_READ \| MAY_WRITE \| MAY_EXEC \| MAY_APPEND \|\
	27	AA_MAY_CREATE \| AA_MAY_DELETE \| \
	28	AA_MAY_META_READ \| AA_MAY_META_WRITE \| \
	29	AA_MAY_CHMOD \| AA_MAY_CHOWN \| AA_MAY_LOCK \| \
	30	AA_EXEC_MMAP \| AA_MAY_LINK)
	31
af7caa8f JJ	32	/* struct aa_file_ctx - the AppArmor context the file was opened in
	33	* @perms: the permission the file was opened with
	34	*
	35	* The file_ctx could currently be directly stored in file->f_security
	36	* as the profile reference is now stored in the f_cred. However the
	37	* ctx struct will expand in the future so we keep the struct.
	38	*/
	39	struct aa_file_ctx {
	40	u16 allow;
	41	};
	42
	43	/**
	44	* aa_alloc_file_context - allocate file_ctx
	45	* @gfp: gfp flags for allocation
	46	*
	47	* Returns: file_ctx or NULL on failure
	48	*/
	49	static inline struct aa_file_ctx *aa_alloc_file_context(gfp_t gfp)
	50	{
	51	return kzalloc(sizeof(struct aa_file_ctx), gfp);
	52	}
	53
	54	/**
	55	* aa_free_file_context - free a file_ctx
	56	* @ctx: file_ctx to free (MAYBE_NULL)
	57	*/
	58	static inline void aa_free_file_context(struct aa_file_ctx *ctx)
	59	{
	60	if (ctx)
	61	kzfree(ctx);
	62	}
	63
6380bd8d JJ	64	/*
	65	* The xindex is broken into 3 parts
	66	* - index - an index into either the exec name table or the variable table
	67	* - exec type - which determines how the executable name and index are used
	68	* - flags - which modify how the destination name is applied
	69	*/
	70	#define AA_X_INDEX_MASK 0x03ff
	71
	72	#define AA_X_TYPE_MASK 0x0c00
	73	#define AA_X_TYPE_SHIFT 10
	74	#define AA_X_NONE 0x0000
	75	#define AA_X_NAME 0x0400 /* use executable name px */
	76	#define AA_X_TABLE 0x0800 /* use a specified name ->n# */
	77
	78	#define AA_X_UNSAFE 0x1000
	79	#define AA_X_CHILD 0x2000 /* make >AA_X_NONE apply to children */
	80	#define AA_X_INHERIT 0x4000
	81	#define AA_X_UNCONFINED 0x8000
	82
	83	/* AA_SECURE_X_NEEDED - is passed in the bprm->unsafe field */
	84	#define AA_SECURE_X_NEEDED 0x8000
	85
	86	/* need to make conditional which ones are being set */
	87	struct path_cond {
2db81452	88	kuid_t uid;
6380bd8d JJ	89	umode_t mode;
	90	};
	91
	92	/* struct file_perms - file permission
	93	* @allow: mask of permissions that are allowed
	94	* @audit: mask of permissions to force an audit message for
	95	* @quiet: mask of permissions to quiet audit messages for
	96	* @kill: mask of permissions that when matched will kill the task
	97	* @xindex: exec transition index if @allow contains MAY_EXEC
	98	*
	99	* The @audit and @queit mask should be mutually exclusive.
	100	*/
	101	struct file_perms {
	102	u32 allow;
	103	u32 audit;
	104	u32 quiet;
	105	u32 kill;
	106	u16 xindex;
	107	};
	108
	109	extern struct file_perms nullperms;
	110
	111	#define COMBINED_PERM_MASK(X) ((X).allow \| (X).audit \| (X).quiet \| (X).kill)
	112
	113	/* FIXME: split perms from dfa and match this to description
	114	* also add delegation info.
	115	*/
	116	static inline u16 dfa_map_xindex(u16 mask)
	117	{
	118	u16 old_index = (mask >> 10) & 0xf;
	119	u16 index = 0;
	120
	121	if (mask & 0x100)
	122	index \|= AA_X_UNSAFE;
	123	if (mask & 0x200)
	124	index \|= AA_X_INHERIT;
	125	if (mask & 0x80)
	126	index \|= AA_X_UNCONFINED;
	127
	128	if (old_index == 1) {
	129	index \|= AA_X_UNCONFINED;
	130	} else if (old_index == 2) {
	131	index \|= AA_X_NAME;
	132	} else if (old_index == 3) {
	133	index \|= AA_X_NAME \| AA_X_CHILD;
8b964eae	134	} else if (old_index) {
6380bd8d JJ	135	index \|= AA_X_TABLE;
	136	index \|= old_index - 4;
	137	}
	138
	139	return index;
	140	}
	141
	142	/*
	143	* map old dfa inline permissions to new format
	144	*/
	145	#define dfa_user_allow(dfa, state) (((ACCEPT_TABLE(dfa)[state]) & 0x7f) \| \
	146	((ACCEPT_TABLE(dfa)[state]) & 0x80000000))
	147	#define dfa_user_audit(dfa, state) ((ACCEPT_TABLE2(dfa)[state]) & 0x7f)
	148	#define dfa_user_quiet(dfa, state) (((ACCEPT_TABLE2(dfa)[state]) >> 7) & 0x7f)
	149	#define dfa_user_xindex(dfa, state) \
	150	(dfa_map_xindex(ACCEPT_TABLE(dfa)[state] & 0x3fff))
	151
	152	#define dfa_other_allow(dfa, state) ((((ACCEPT_TABLE(dfa)[state]) >> 14) & \
	153	0x7f) \| \
	154	((ACCEPT_TABLE(dfa)[state]) & 0x80000000))
	155	#define dfa_other_audit(dfa, state) (((ACCEPT_TABLE2(dfa)[state]) >> 14) & 0x7f)
	156	#define dfa_other_quiet(dfa, state) \
	157	((((ACCEPT_TABLE2(dfa)[state]) >> 7) >> 14) & 0x7f)
	158	#define dfa_other_xindex(dfa, state) \
	159	dfa_map_xindex((ACCEPT_TABLE(dfa)[state] >> 14) & 0x3fff)
	160
	161	int aa_audit_file(struct aa_profile profile, struct file_perms perms,
ef88a7ac	162	const char op, u32 request, const char name,
2db81452	163	const char target, kuid_t ouid, const char info, int error);
6380bd8d JJ	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	unsigned int aa_str_perms(struct aa_dfa *dfa, unsigned int start,
	185	const char name, struct path_cond cond,
	186	struct file_perms *perms);
	187
47f6e5cc JJ	188	int aa_path_perm(const char op, struct aa_profile profile,
	189	const struct path *path, int flags, u32 request,
	190	struct path_cond *cond);
6380bd8d JJ	191
6380bd8d JJ	192	int aa_path_link(struct aa_profile profile, struct dentry old_dentry,
3539aaf6	193	const struct path new_dir, struct dentry new_dentry);
6380bd8d	194
47f6e5cc	195	int aa_file_perm(const char op, struct aa_profile profile, struct file *file,
6380bd8d JJ	196	u32 request);
	197
	198	static inline void aa_free_file_rules(struct aa_file_rules *rules)
	199	{
	200	aa_put_dfa(rules->dfa);
	201	aa_free_domain_entries(&rules->trans);
	202	}
	203
6380bd8d JJ	204	/**
	205	* aa_map_file_perms - map file flags to AppArmor permissions
	206	* @file: open file to map flags to AppArmor permissions
	207	*
	208	* Returns: apparmor permission set for the file
	209	*/
	210	static inline u32 aa_map_file_to_perms(struct file *file)
	211	{
53fe8b99 JJ	212	int flags = file->f_flags;
	213	u32 perms = 0;
	214
	215	if (file->f_mode & FMODE_WRITE)
	216	perms \|= MAY_WRITE;
	217	if (file->f_mode & FMODE_READ)
	218	perms \|= MAY_READ;
6380bd8d JJ	219
	220	if ((flags & O_APPEND) && (perms & MAY_WRITE))
	221	perms = (perms & ~MAY_WRITE) \| MAY_APPEND;
	222	/* trunc implies write permission */
	223	if (flags & O_TRUNC)
	224	perms \|= MAY_WRITE;
	225	if (flags & O_CREAT)
	226	perms \|= AA_MAY_CREATE;
	227
	228	return perms;
	229	}
	230
	231	#endif /* __AA_FILE_H */