add support for AUDIT_PERM predicate
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Add support for a rule key, which can be used to tie audit records to audit
rules.  This is useful when a watched file is accessed through a link or
symlink, as well as for general audit log analysis.

Because this patch uses a string key instead of an integer key, there is a bit
of extra overhead to do the kstrdup() when a rule fires.  However, we're also
allocating memory for the audit record buffer, so it's probably not that
significant.  I went ahead with a string key because it seems more
user-friendly.

Note that the user must ensure that filterkeys are unique.  The kernel only
checks for duplicate rules.
Signed-off-by: NAmy Griffis <amy.griffis@hpd.com>

When an audit event involves changes to a directory entry, include
a PATH record for the directory itself.  A few other notable changes:

    - fixed audit_inode_child() hooks in fsnotify_move()
    - removed unused flags arg from audit_inode()
    - added audit log routines for logging a portion of a string

Here's some sample output.

before patch:
type=SYSCALL msg=audit(1149821605.320:26): arch=40000003 syscall=39 success=yes exit=0 a0=bf8d3c7c a1=1ff a2=804e1b8 a3=bf8d3c7c items=1 ppid=739 pid=800 auid=0 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 tty=ttyS0 comm="mkdir" exe="/bin/mkdir" subj=root:system_r:unconfined_t:s0-s0:c0.c255
type=CWD msg=audit(1149821605.320:26):  cwd="/root"
type=PATH msg=audit(1149821605.320:26): item=0 name="foo" parent=164068 inode=164010 dev=03:00 mode=040755 ouid=0 ogid=0 rdev=00:00 obj=root:object_r:user_home_t:s0

after patch:
type=SYSCALL msg=audit(1149822032.332:24): arch=40000003 syscall=39 success=yes exit=0 a0=bfdd9c7c a1=1ff a2=804e1b8 a3=bfdd9c7c items=2 ppid=714 pid=777 auid=0 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 tty=ttyS0 comm="mkdir" exe="/bin/mkdir" subj=root:system_r:unconfined_t:s0-s0:c0.c255
type=CWD msg=audit(1149822032.332:24):  cwd="/root"
type=PATH msg=audit(1149822032.332:24): item=0 name="/root" inode=164068 dev=03:00 mode=040750 ouid=0 ogid=0 rdev=00:00 obj=root:object_r:user_home_dir_t:s0
type=PATH msg=audit(1149822032.332:24): item=1 name="foo" inode=164010 dev=03:00 mode=040755 ouid=0 ogid=0 rdev=00:00 obj=root:object_r:user_home_t:s0
Signed-off-by: NAmy Griffis <amy.griffis@hp.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

In this implementation, audit registers inotify watches on the parent
directories of paths specified in audit rules.  When audit's inotify
event handler is called, it updates any affected rules based on the
filesystem event.  If the parent directory is renamed, removed, or its
filesystem is unmounted, audit removes all rules referencing that
inotify watch.

To keep things simple, this implementation limits location-based
auditing to the directory entries in an existing directory.  Given
a path-based rule for /foo/bar/passwd, the following table applies:

    passwd modified -- audit event logged
    passwd replaced -- audit event logged, rules list updated
    bar renamed     -- rule removed
    foo renamed     -- untracked, meaning that the rule now applies to
		       the new location

Audit users typically want to have many rules referencing filesystem
objects, which can significantly impact filtering performance.  This
patch also adds an inode-number-based rule hash to mitigate this
situation.

The patch is relative to the audit git tree:
http://kernel.org/git/?p=linux/kernel/git/viro/audit-current.git;a=summary
and uses the inotify kernel API:
http://lkml.org/lkml/2006/6/1/145Signed-off-by: NAmy Griffis <amy.griffis@hp.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

We should not send a pile of replies while holding audit_netlink_mutex
since we hold the same mutex when we receive commands.  As the result,
we can get blocked while sending and sit there holding the mutex while
auditctl is unable to send the next command and get around to receiving
what we'd sent.

Solution: create skb and put them into a queue instead of sending;
once we are done, send what we've got on the list.  The former can
be done synchronously while we are handling AUDIT_LIST or AUDIT_LIST_RULES;
we are holding audit_netlink_mutex at that point.  The latter is done
asynchronously and without messing with audit_netlink_mutex.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

This patch provides the ability to filter audit messages based on the
elements of the process' SELinux context (user, role, type, mls sensitivity,
and mls clearance).  It uses the new interfaces from selinux to opaquely
store information related to the selinux context and to filter based on that
information.  It also uses the callback mechanism provided by selinux to
refresh the information when a new policy is loaded.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Semaphore to mutex conversion.

The conversion was generated via scripts, and the result was validated
automatically via a script as well.
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Updated patch to dynamically allocate audit rule fields in kernel's
internal representation.  Added unlikely() calls for testing memory
allocation result.

Amy Griffis wrote:     [Wed Jan 11 2006, 02:02:31PM EST]
> Modify audit's kernel-userspace interface to allow the specification
> of string fields in audit rules.
>
> Signed-off-by: Amy Griffis <amy.griffis@hp.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
(cherry picked from 5ffc4a863f92351b720fe3e9c5cd647accff9e03 commit)

This fixes the per-user and per-message-type filtering when syscall
auditing isn't enabled.

[AV: folded followup fix from the same author]
Signed-off-by: NDavid Woodhouse <dwmw2@infradead.org>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>