Commit Graph

572 Commits

Author SHA1 Message Date
Eric Paris 932995f0ce IMA: Add __init notation to ima functions
A number of IMA functions only used during init are not marked with __init.
Add those notations so they are freed automatically.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-05-22 09:34:21 +10:00
Eric Paris 5789ba3bd0 IMA: Minimal IMA policy and boot param for TCB IMA policy
The IMA TCB policy is dangerous.  A normal use can use all of a system's
memory (which cannot be freed) simply by building and running lots of
executables.  The TCB policy is also nearly useless because logging in as root
often causes a policy violation when dealing with utmp, thus rendering the
measurements meaningless.

There is no good fix for this in the kernel.  A full TCB policy would need to
be loaded in userspace using LSM rule matching to get both a protected and
useful system.  But, if too little is measured before userspace can load a real
policy one again ends up with a meaningless set of measurements.  One option
would be to put the policy load inside the initrd in order to get it early
enough in the boot sequence to be useful, but this runs into trouble with the
LSM.  For IMA to measure the LSM policy and the LSM policy loading mechanism
it needs rules to do so, but we already talked about problems with defaulting
to such broad rules....

IMA also depends on the files being measured to be on an FS which implements
and supports i_version.  Since the only FS with this support (ext4) doesn't
even use it by default it seems silly to have any IMA rules by default.

This should reduce the performance overhead of IMA to near 0 while still
letting users who choose to configure their machine as such to inclue the
ima_tcb kernel paramenter and get measurements during boot before they can
load a customized, reasonable policy in userspace.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-05-22 09:31:20 +10:00
Eric Paris 75834fc3b6 SELinux: move SELINUX_MAGIC into magic.h
The selinuxfs superblock magic is used inside the IMA code, but is being
defined in two places and could someday get out of sync.  This patch moves the
declaration into magic.h so it is only done once.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-05-19 08:19:00 +10:00
Eric Paris c3d20103d0 IMA: do not measure everything opened by root by default
The IMA default policy measures every single file opened by root.  This is
terrible for most users.  Consider a system (like mine) with virtual machine
images.  When those images are touched (which happens at boot for me) those
images are measured.  This is just way too much for the default case.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-05-15 09:55:44 +10:00
Eric Paris f850a7c040 IMA: remove read permissions on the ima policy file
The IMA policy file does not implement read.  Trying to just open/read/close
the file will load a blank policy and you cannot then change the policy
without a reboot.  This removes the read permission from the file so one must
at least be attempting to write...

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-05-15 09:55:41 +10:00
Eric Paris 1a62e958fa IMA: open all files O_LARGEFILE
If IMA tried to measure a file which was larger than 4G dentry_open would fail
with -EOVERFLOW since IMA wasn't passing O_LARGEFILE.  This patch passes
O_LARGEFILE to all IMA opens to avoid this problem.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-05-12 11:06:08 +10:00
Eric Paris f06dd16a03 IMA: Handle dentry_open failures
Currently IMA does not handle failures from dentry_open().  This means that we
leave a pointer set to ERR_PTR(errno) and then try to use it just a few lines
later in fput().  Oops.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-05-12 11:06:04 +10:00
Eric Paris 37bcbf13d3 IMA: use current_cred() instead of current->cred
Proper invocation of the current credentials is to use current_cred() not
current->cred.  This patches makes IMA use the new method.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-05-12 11:06:01 +10:00
Mimi Zohar 07ff7a0b18 integrity: remove __setup auditing msgs
Remove integrity audit messages from __setup()

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-05-06 10:35:59 +10:00
Mimi Zohar e5e520a715 integrity: use audit_log_string
Based on a request from Eric Paris to simplify parsing, replace
audit_log_format statements containing "%s" with audit_log_string().

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-05-06 10:35:56 +10:00
Mimi Zohar 53fc0e2259 integrity: lsm audit rule matching fix
An audit subsystem change replaced AUDIT_EQUAL with Audit_equal.
Update calls to security_filter_rule_init()/match() to reflect
the change.

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-05-06 10:35:53 +10:00
Jiri Pirko 05725f7eb4 rculist: use list_entry_rcu in places where it's appropriate
Use previously introduced list_entry_rcu instead of an open-coded
list_entry + rcu_dereference combination.

Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: dipankar@in.ibm.com
LKML-Reference: <20090414181715.GA3634@psychotron.englab.brq.redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-04-15 12:05:25 +02:00
Mimi Zohar be38e0fd5f integrity: ima iint radix_tree_lookup locking fix
Based on Andrew Morton's comments:
- add missing locks around radix_tree_lookup in ima_iint_insert()

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: James Morris <jmorris@namei.org>
2009-02-23 09:54:53 +11:00
Mimi Zohar 0da0a420bb integrity: ima scatterlist bug fix
Based on Alexander Beregalov's post http://lkml.org/lkml/2009/2/19/198

- replaced sg_set_buf() with sg_init_one()

 kernel BUG at include/linux/scatterlist.h:65!
 invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
 last sysfs file:
 CPU 2
 Modules linked in:
 Pid: 1, comm: swapper Not tainted 2.6.29-rc5-next-20090219 #5 PowerEdge 1950
 RIP: 0010:[<ffffffff8045ec70>]  [<ffffffff8045ec70>] ima_calc_hash+0xc0/0x160
 RSP: 0018:ffff88007f46bc40  EFLAGS: 00010286
 RAX: ffffe200032c45e8 RBX: 00000000fffffff4 RCX: 0000000087654321
 RDX: 0000000000000002 RSI: 0000000000000001 RDI: ffff88007cf71048
 RBP: ffff88007f46bcd0 R08: 0000000000000000 R09: 0000000000000163
 R10: ffff88007f4707a8 R11: 0000000000000000 R12: ffff88007cf71048
 R13: 0000000000001000 R14: 0000000000000000 R15: 0000000000009d98
 FS:  0000000000000000(0000) GS:ffff8800051ac000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0018 ES: 0018 CR0: 000000008005003b
 CR2: 0000000000000000 CR3: 0000000000201000 CR4: 00000000000006e0
 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Tested-by: Alexander Beregalov <a.beregalov@gmail.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-02-21 00:29:59 +11:00
Randy Dunlap b53fab9d48 ima: fix build error
IMA_LSM_RULES requires AUDIT.  This is automatic if SECURITY_SELINUX=y
but not when SECURITY_SMACK=y (and SECURITY_SELINUX=n), so make the
dependency explicit.  This fixes the following build error:

security/integrity/ima/ima_policy.c:111:error: implicit declaration of function 'security_audit_rule_match'
security/integrity/ima/ima_policy.c:230:error: implicit declaration of function 'security_audit_rule_init'

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Acked-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-02-13 09:27:56 +11:00
Mimi Zohar 523979adfa integrity: audit update
Based on discussions on linux-audit, as per Steve Grubb's request
http://lkml.org/lkml/2009/2/6/269, the following changes were made:
- forced audit result to be either 0 or 1.
- made template names const
- Added new stand-alone message type: AUDIT_INTEGRITY_RULE

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Acked-by: Steve Grubb <sgrubb@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-02-12 09:40:14 +11:00
James Morris 64c61d80a6 IMA: fix ima_delete_rules() definition
Fix ima_delete_rules() definition so sparse doesn't complain.

Signed-off-by: James Morris <jmorris@namei.org>
2009-02-06 09:05:34 +11:00
Mimi Zohar 1df9f0a731 Integrity: IMA file free imbalance
The number of calls to ima_path_check()/ima_file_free()
should be balanced.  An extra call to fput(), indicates
the file could have been accessed without first being
measured.

Although f_count is incremented/decremented in places other
than fget/fput, like fget_light/fput_light and get_file, the
current task must already hold a file refcnt.  The call to
__fput() is delayed until the refcnt becomes 0, resulting
in ima_file_free() flagging any changes.

- add hook to increment opencount for IPC shared memory(SYSV),
  shmat files, and /dev/zero
- moved NULL iint test in opencount_get()

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-02-06 09:05:33 +11:00
Mimi Zohar f4bd857bc8 integrity: IMA policy open
Sequentialize access to the policy file
- permit multiple attempts to replace default policy with a valid policy

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-02-06 09:05:32 +11:00
Mimi Zohar 4af4662fa4 integrity: IMA policy
Support for a user loadable policy through securityfs
with support for LSM specific policy data.
- free invalid rule in ima_parse_add_rule()

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-02-06 09:05:31 +11:00
Mimi Zohar bab7393787 integrity: IMA display
Make the measurement lists available through securityfs.
- removed test for NULL return code from securityfs_create_file/dir

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-02-06 09:05:31 +11:00
Mimi Zohar 3323eec921 integrity: IMA as an integrity service provider
IMA provides hardware (TPM) based measurement and attestation for
file measurements. As the Trusted Computing (TPM) model requires,
IMA measures all files before they are accessed in any way (on the
integrity_bprm_check, integrity_path_check and integrity_file_mmap
hooks), and commits the measurements to the TPM. Once added to the
TPM, measurements can not be removed.

In addition, IMA maintains a list of these file measurements, which
can be used to validate the aggregate value stored in the TPM.  The
TPM can sign these measurements, and thus the system can prove, to
itself and to a third party, the system's integrity in a way that
cannot be circumvented by malicious or compromised software.

- alloc ima_template_entry before calling ima_store_template()
- log ima_add_boot_aggregate() failure
- removed unused IMA_TEMPLATE_NAME_LEN
- replaced hard coded string length with #define name

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-02-06 09:05:30 +11:00