[deliverable/linux.git] / Documentation / ABI / testing / ima_policy

What:		security/ima/policy
Date:		May 2008
Contact:	Mimi Zohar <zohar@us.ibm.com>
Description:
		The Trusted Computing Group(TCG) runtime Integrity
		Measurement Architecture(IMA) maintains a list of hash
		values of executables and other sensitive system files
		loaded into the run-time of this system.  At runtime,
		the policy can be constrained based on LSM specific data.
		Policies are loaded into the securityfs file ima/policy
		by opening the file, writing the rules one at a time and
		then closing the file.  The new policy takes effect after
		the file ima/policy is closed.

		IMA appraisal, if configured, uses these file measurements
		for local measurement appraisal.

		rule format: action [condition ...]

		action: measure | dont_measure | appraise | dont_appraise | audit
		condition:= base | lsm  [option]
			base:	[[func=] [mask=] [fsmagic=] [fsuuid=] [uid=]
				[euid=] [fowner=]]
			lsm:	[[subj_user=] [subj_role=] [subj_type=]
				 [obj_user=] [obj_role=] [obj_type=]]
			option:	[[appraise_type=]] [permit_directio]

		base: 	func:= [BPRM_CHECK][MMAP_CHECK][FILE_CHECK][MODULE_CHECK]
				[FIRMWARE_CHECK]
				[KEXEC_KERNEL_CHECK] [KEXEC_INITRAMFS_CHECK]
			mask:= [[^]MAY_READ] [[^]MAY_WRITE] [[^]MAY_APPEND]
			       [[^]MAY_EXEC]
			fsmagic:= hex value
			fsuuid:= file system UUID (e.g 8bcbe394-4f13-4144-be8e-5aa9ea2ce2f6)
			uid:= decimal value
			euid:= decimal value
			fowner:=decimal value
		lsm:  	are LSM specific
		option:	appraise_type:= [imasig]

		default policy:
			# PROC_SUPER_MAGIC
			dont_measure fsmagic=0x9fa0
			dont_appraise fsmagic=0x9fa0
			# SYSFS_MAGIC
			dont_measure fsmagic=0x62656572
			dont_appraise fsmagic=0x62656572
			# DEBUGFS_MAGIC
			dont_measure fsmagic=0x64626720
			dont_appraise fsmagic=0x64626720
			# TMPFS_MAGIC
			dont_measure fsmagic=0x01021994
			dont_appraise fsmagic=0x01021994
			# RAMFS_MAGIC
			dont_appraise fsmagic=0x858458f6
			# DEVPTS_SUPER_MAGIC
			dont_measure fsmagic=0x1cd1
			dont_appraise fsmagic=0x1cd1
			# BINFMTFS_MAGIC
			dont_measure fsmagic=0x42494e4d
			dont_appraise fsmagic=0x42494e4d
			# SECURITYFS_MAGIC
			dont_measure fsmagic=0x73636673
			dont_appraise fsmagic=0x73636673
			# SELINUX_MAGIC
			dont_measure fsmagic=0xf97cff8c
			dont_appraise fsmagic=0xf97cff8c
			# CGROUP_SUPER_MAGIC
			dont_measure fsmagic=0x27e0eb
			dont_appraise fsmagic=0x27e0eb
			# NSFS_MAGIC
			dont_measure fsmagic=0x6e736673
			dont_appraise fsmagic=0x6e736673

			measure func=BPRM_CHECK
			measure func=FILE_MMAP mask=MAY_EXEC
			measure func=FILE_CHECK mask=MAY_READ uid=0
			measure func=MODULE_CHECK
			measure func=FIRMWARE_CHECK
			appraise fowner=0

		The default policy measures all executables in bprm_check,
		all files mmapped executable in file_mmap, and all files
		open for read by root in do_filp_open.  The default appraisal
		policy appraises all files owned by root.

		Examples of LSM specific definitions:

		SELinux:
			dont_measure obj_type=var_log_t
			dont_appraise obj_type=var_log_t
			dont_measure obj_type=auditd_log_t
			dont_appraise obj_type=auditd_log_t
			measure subj_user=system_u func=FILE_CHECK mask=MAY_READ
			measure subj_role=system_r func=FILE_CHECK mask=MAY_READ

		Smack:
			measure subj_user=_ func=FILE_CHECK mask=MAY_READ
Commit	Line	Data
4af4662f MZ	1	What: security/ima/policy
	2	Date: May 2008
	3	Contact: Mimi Zohar <zohar@us.ibm.com>
	4	Description:
	5	The Trusted Computing Group(TCG) runtime Integrity
	6	Measurement Architecture(IMA) maintains a list of hash
	7	values of executables and other sensitive system files
	8	loaded into the run-time of this system. At runtime,
	9	the policy can be constrained based on LSM specific data.
	10	Policies are loaded into the securityfs file ima/policy
	11	by opening the file, writing the rules one at a time and
	12	then closing the file. The new policy takes effect after
	13	the file ima/policy is closed.
	14
07f6a794 MZ	15	IMA appraisal, if configured, uses these file measurements
	16	for local measurement appraisal.
	17
4af4662f MZ	18	rule format: action [condition ...]
4af4662f MZ	19
e7c568e0	20	action: measure \| dont_measure \| appraise \| dont_appraise \| audit
0e5a247c	21	condition:= base \| lsm [option]
85865c1f	22	base: [[func=] [mask=] [fsmagic=] [fsuuid=] [uid=]
139069ef	23	[euid=] [fowner=]]
4af4662f MZ	24	lsm: [[subj_user=] [subj_role=] [subj_type=]
4af4662f MZ	25	[obj_user=] [obj_role=] [obj_type=]]
f9b2a735	26	option: [[appraise_type=]] [permit_directio]
4af4662f	27
16cac49f	28	base: func:= [BPRM_CHECK][MMAP_CHECK][FILE_CHECK][MODULE_CHECK]
5a9196d7	29	[FIRMWARE_CHECK]
d9ddf077	30	[KEXEC_KERNEL_CHECK] [KEXEC_INITRAMFS_CHECK]
4351c294 MZ	31	mask:= [[^]MAY_READ] [[^]MAY_WRITE] [[^]MAY_APPEND]
4351c294 MZ	32	[[^]MAY_EXEC]
4af4662f	33	fsmagic:= hex value
85865c1f	34	fsuuid:= file system UUID (e.g 8bcbe394-4f13-4144-be8e-5aa9ea2ce2f6)
4af4662f	35	uid:= decimal value
139069ef	36	euid:= decimal value
07f6a794	37	fowner:=decimal value
4af4662f	38	lsm: are LSM specific
0e5a247c	39	option: appraise_type:= [imasig]
4af4662f MZ	40
	41	default policy:
	42	# PROC_SUPER_MAGIC
	43	dont_measure fsmagic=0x9fa0
07f6a794	44	dont_appraise fsmagic=0x9fa0
4af4662f MZ	45	# SYSFS_MAGIC
4af4662f MZ	46	dont_measure fsmagic=0x62656572
07f6a794	47	dont_appraise fsmagic=0x62656572
4af4662f MZ	48	# DEBUGFS_MAGIC
4af4662f MZ	49	dont_measure fsmagic=0x64626720
07f6a794	50	dont_appraise fsmagic=0x64626720
4af4662f MZ	51	# TMPFS_MAGIC
4af4662f MZ	52	dont_measure fsmagic=0x01021994
07f6a794 MZ	53	dont_appraise fsmagic=0x01021994
07f6a794 MZ	54	# RAMFS_MAGIC
07f6a794	55	dont_appraise fsmagic=0x858458f6
6438de9f RS	56	# DEVPTS_SUPER_MAGIC
	57	dont_measure fsmagic=0x1cd1
	58	dont_appraise fsmagic=0x1cd1
	59	# BINFMTFS_MAGIC
	60	dont_measure fsmagic=0x42494e4d
	61	dont_appraise fsmagic=0x42494e4d
4af4662f MZ	62	# SECURITYFS_MAGIC
4af4662f MZ	63	dont_measure fsmagic=0x73636673
07f6a794	64	dont_appraise fsmagic=0x73636673
6438de9f RS	65	# SELINUX_MAGIC
	66	dont_measure fsmagic=0xf97cff8c
	67	dont_appraise fsmagic=0xf97cff8c
	68	# CGROUP_SUPER_MAGIC
	69	dont_measure fsmagic=0x27e0eb
	70	dont_appraise fsmagic=0x27e0eb
cd025f7f MZ	71	# NSFS_MAGIC
	72	dont_measure fsmagic=0x6e736673
	73	dont_appraise fsmagic=0x6e736673
4af4662f MZ	74
	75	measure func=BPRM_CHECK
	76	measure func=FILE_MMAP mask=MAY_EXEC
1e93d005	77	measure func=FILE_CHECK mask=MAY_READ uid=0
5a9196d7 MZ	78	measure func=MODULE_CHECK
5a9196d7 MZ	79	measure func=FIRMWARE_CHECK
07f6a794	80	appraise fowner=0
4af4662f MZ	81
	82	The default policy measures all executables in bprm_check,
	83	all files mmapped executable in file_mmap, and all files
07f6a794 MZ	84	open for read by root in do_filp_open. The default appraisal
07f6a794 MZ	85	policy appraises all files owned by root.
4af4662f MZ	86
	87	Examples of LSM specific definitions:
	88
	89	SELinux:
4af4662f	90	dont_measure obj_type=var_log_t
07f6a794	91	dont_appraise obj_type=var_log_t
4af4662f	92	dont_measure obj_type=auditd_log_t
07f6a794	93	dont_appraise obj_type=auditd_log_t
1e93d005 MZ	94	measure subj_user=system_u func=FILE_CHECK mask=MAY_READ
1e93d005 MZ	95	measure subj_role=system_r func=FILE_CHECK mask=MAY_READ
4af4662f MZ	96
4af4662f MZ	97	Smack:
1e93d005	98	measure subj_user=_ func=FILE_CHECK mask=MAY_READ