not trust jails enough to execute audit related system calls. An example of
this is with su(1), or login(1) within prisons. So, if the syscall request
comes from a jail return ENOSYS. This will cause these utilities to operate
as if audit is not present in the kernel.
Looking forward, this problem will be remedied by allowing non privileged
users to maintain and their own audit streams, but the details on exactly how
this will be implemented needs to be worked out.
This change should fix situations when options AUDIT has been compiled into
the kernel, and utilities like su(1), or login(1) fail due to audit system
call failures within jails.
This is a RELENG_6 candidate.
Reported by: Christian Brueffer
Discussed with: rwatson
MFC after: 3 days
written to the audit trail file:
- audit_record_write() now returns void, and all file system specific
error handling occurs inside this function. This pushes error handling
complexity out of the record demux routine that hands off to both the
trail and audit pipes, and makes trail behavior more consistent with
pipes as a record destination.
- Rate limit kernel printfs associated with running low on space. Rate
limit audit triggers for low space. Rate limit printfs for fail stop
events. Rate limit audit worker write error printfs.
- Document in detail the types of limits and space checks we perform, and
combine common cases.
This improves the audit subsystems tolerance to low space conditions by
avoiding toasting the console with printfs are waking up the audit daemon
continuously.
MFC after: 3 days
Obtained from: TrustedBSD Project
when allocating the record in the first place, allocate the final buffer
when closing the BSM record. At that point, more size information is
available, so a sufficiently large buffer can be allocated.
This allows the kernel to generate audit records in excess of
MAXAUDITDATA bytes, but is consistent with Solaris's behavior. This only
comes up when auditing command line arguments, in which case we presume
the administrator really does want the data as they have specified the
policy flag to gather them.
Obtained from: TrustedBSD Project
MFC after: 3 days
audit pipes. If the kernel record was not selected for the trail or the pipe,
any user supplied record attached to it would be tossed away, resulting in
otherwise selected events being lost.
- Introduce two new masks: AR_PRESELECT_USER_TRAIL AR_PRESELECT_USER_PIPE,
currently we have AR_PRESELECT_TRAIL and AR_PRESELECT_PIPE, which tells
the audit worker that we are interested in the kernel record, with
the additional masks we can determine if either the pipe or trail is
interested in seeing the kernel or user record.
- In audit(2), we unconditionally set the AR_PRESELECT_USER_TRAIL and
AR_PRESELECT_USER_PIPE masks under the assumption that userspace has
done the preselection [1].
Currently, there is work being done that allows the kernel to parse and
preselect user supplied records, so in the future preselection could occur
in either layer. But there is still a few details to work out here.
[1] At some point we need to teach au_preselect(3) about the interests of
all the individual audit pipes.
This is a RELENG_6 candidate.
Reviewed by: rwatson
Obtained from: TrustedBSD Project
MFC after: 1 week
Add the argument auditing functions for argv and env.
Add kernel-specific versions of the tokenizer functions for the
arg and env represented as a char array.
Implement the AUDIT_ARGV and AUDIT_ARGE audit policy commands to
enable/disable argv/env auditing.
Call the argument auditing from the exec system calls.
Obtained from: TrustedBSD Project
Approved by: rwatson (mentor)
audit record size at run-time, which can be used by the user
process to size the user space buffer it reads into from the audit
pipe.
Perforce change: 105098
Obtained from: TrustedBSD Project
progress the kernel audit code in CVS is considered authoritative.
This will ease $P4$-related merging issues during the CVS loopback.
Obtained from: TrustedBSD Project
- Correct audit_arg_socketaddr() argument name from so to sa.
- Assert arguments are non-NULL to many argument capture functions
rather than testing them. This may trip some bugs.
- Assert the process lock is held when auditing process
information.
- Test currecord in several more places.
- Test validity of more arguments with kasserts, such as flag
values when auditing vnode information.
Perforce change: 98825
Obtained from: TrustedBSD Project
whether we have an IPv6 address. Write the term ID as 4 or
16 bytes depending on address type. This change matches the recent
OpenBSM change, and what Solaris does.
Obtained from: TrustedBSD Project
Approved by: rwatson (mentor)
get a consistent snapshot, as well as get consistent values (i.e.,
that p_comm is properly nul-terminated).
Perforce CID: 98824
Obtained from: TrustedBSD Project
process was sucessfully audited. Otherwise, generate the PID
token. This change covers the pid < 0 cases, and pid lookup
failure cases.
Submitted by: wsalamon
Obtained from: TrustedBSD Project
global audit trail configuration. This allows applications consuming
audit trails to specify parameters for which audit records are of
interest, including selecting records not required by the global trail.
Allowing application interest specification without changing the global
configuration allows intrusion detection systems to run without
interfering with global auditing or each other (if multiple are
present). To implement this:
- Kernel audit records now carry a flag to indicate whether they have
been selected by the global trail or by the audit pipe subsystem,
set during record commit, so that this information is available
after BSM conversion when delivering the BSM to the trail and audit
pipes in the audit worker thread asynchronously. Preselection by
either record target will cause the record to be kept.
- Similar changes to preselection when the audit record is created
when the system call is entering: consult both the global trail and
pipes.
- au_preselect() now accepts the class in order to avoid repeatedly
looking up the mask for each preselection test.
- Define a series of ioctls that allow applications to specify whether
they want to track the global trail, or program their own
preselection parameters: they may specify their own flags and naflags
masks, similar to the global masks of the same name, as well as a set
of per-auid masks. They also set a per-pipe mode specifying whether
they track the global trail, or user their own -- the door is left
open for future additional modes. A new ioctl is defined to allow a
user process to flush the current audit pipe queue, which can be used
after reprogramming pre-selection to make sure that only records of
interest are received in future reads.
- Audit pipe data structures are extended to hold the additional fields
necessary to support preselection. By default, audit pipes track the
global trail, so "praudit /dev/auditpipe" will track the global audit
trail even though praudit doesn't program the audit pipe selection
model.
- Comment about the complexities of potentially adding partial read
support to audit pipes.
By using a set of ioctls, applications can select which records are of
interest, and toggle the preselection mode.
Obtained from: TrustedBSD Project
knowledge of user vs. kernel audit records into
audit_worker_process_record(). This largely confines vnode
knowledge to audit_record_write(), but avoids that logic knowing
about BSM as opposed to byte streams. This will allow us to
improve our ability to support real-time audit stream processing
by audit pipe consumers while auditing is disabled, but this
support is not yet complete.
Obtained from: TrustedBSD Project
Break out logic to call audit_record_write() and handle error
conditions into audit_worker_process_record(). This will be the
future home of some logic now present in audit_record_write()
also.
Obtained from: TrustedBSD Project
worker.
Rename audit_commit_cv to audit_watermark_cv, since it is there to
wake up threads waiting on hitting the low watermark. Describe
properly in comment.
Obtained from: TrustedBSD Project
src/sys/security/audit:
- Clarify and clean up AUR_ types to match Solaris.
- Clean up use of host vs. network byte order for IP addresses.
- Remove combined user/kernel implementations of some token creation
calls, such as au_to_file(), header calls, etc.
Obtained from: TrustedBSD Project
branch:
Integrate audit.c to audit_worker.c, so as to migrate the worker
thread implementation to its own .c file.
Populate audit_worker.c using parts now removed from audit.c:
- Move audit rotation global variables.
- Move audit_record_write(), audit_worker_rotate(),
audit_worker_drain(), audit_worker(), audit_rotate_vnode().
- Create audit_worker_init() from relevant parts of audit_init(),
which now calls this routine.
- Recreate audit_free(), which wraps uma_zfree() so that
audit_record_zone can be static to audit.c.
- Unstaticize various types and variables relating to the audit
record queue so that audit_worker can get to them. We may want
to wrap these in accessor methods at some point.
- Move AUDIT_PRINTF() to audit_private.h.
Addition of audit_worker.c to kernel configuration, missed in
earlier submit.
Obtained from: TrustedBSD Project
Add ioctls to audit pipes in order to allow querying of the current
record queue state, setting of the queue limit, and querying of pipe
statistics.
Obtained from: TrustedBSD Project
Change send_trigger() prototype to return an int, so that user
space callers can tell if the message was successfully placed
in the trigger queue. This isn't quite the same as it being
successfully received, but is close enough that we can generate
a more useful warning message in audit(8).
Obtained from: TrustedBSD Project
- Include audit_internal.h to get definition of internal audit record
structures, as it's no longer in audit.h. Forward declare au_record
in audit_private.h as not all audit_private.h consumers care about
it.
- Remove __APPLE__ compatibility bits that are subsumed by configure
for user space.
- Don't expose in6_addr internals (non-portable, but also cleaner
looking).
- Avoid nested include of audit.h in audit_private.h.
Obtained from: TrustedBSD Project
In the future, we may want to acquire the lock early in the function and
hold it across calls to vn_rdwr(), etc, to avoid multiple acquires.
Spotted by: kris (bugmagnet)
Obtained from: TrustedBSD Project
applications to insert a "tee" in the live audit event stream. Records
are inserted into a per-clone queue so that user processes can pull
discreet records out of the queue. Unlike delivery to disk, audit pipes
are "lossy", dropping records in low memory conditions or when the
process falls behind real-time events. This mechanism is appropriate
for use by live monitoring systems, host-based intrusion detection, etc,
and avoids applications having to dig through active on-disk trails that
are owned by the audit daemon.
Obtained from: TrustedBSD Project
initialization routines into a ctor, tear-down to a dtor, cleaning
up, etc. This will allow audit records to be allocated from
per-cpu caches.
On recent FreeBSD, dropping the audit_mtx around freeing to UMA is
no longer required (at one point it was possible to acquire Giant
on that path), so a mutex-free thread-local drain is no longer
required.
Obtained from: TrustedBSD Project
This should not happen, but with this assert, brueffer and I would
not have spent 45 minutes trying to figure out why he wasn't
seeing audit records with the audit version in CVS.
Obtained from: TrustedBSD Project
an incompatible conversion from a 64-bit pointer to a 32-bit integer on
64-bit platforms. We will investigate whether Solaris uses a 64-bit
token here, or a new record here, in order to avoid truncating user
pointers that are 64-bit. However, in the mean time, truncation is fine
as these are rarely/never used fields in audit records.
Obtained from: TrustedBSD Project
- td_ar to struct thread, which holds the in-progress audit record during
a system call.
- p_au to struct proc, which holds per-process audit state, such as the
audit identifier, audit terminal, and process audit masks.
In the earlier implementation, td_ar was added to the zero'd section of
struct thread. In order to facilitate merging to RELENG_6, it has been
moved to the end of the data structure, requiring explicit
initalization in the thread constructor.
Much help from: wsalamon
Obtained from: TrustedBSD Project
- Management of audit state on processes.
- Audit system calls to configure process and system audit state.
- Reliable audit record queue implementation, audit_worker kernel
thread to asynchronously store records on disk.
- Audit event argument.
- Internal audit data structure -> BSM audit trail conversion library.
- Audit event pre-selection.
- Audit pseudo-device permitting kernel->user upcalls to notify auditd
of kernel audit events.
Much work by: wsalamon
Obtained from: TrustedBSD Project, Apple Computer, Inc.
