privilege for threads and credentials. Unlike the existing suser(9)
interface, priv(9) exposes a named privilege identifier to the privilege
checking code, allowing more complex policies regarding the granting of
privilege to be expressed. Two interfaces are provided, replacing the
existing suser(9) interface:
suser(td) -> priv_check(td, priv)
suser_cred(cred, flags) -> priv_check_cred(cred, priv, flags)
A comprehensive list of currently available kernel privileges may be
found in priv.h. New privileges are easily added as required, but the
comments on adding privileges found in priv.h and priv(9) should be read
before doing so.
The new privilege interface exposed sufficient information to the
privilege checking routine that it will now be possible for jail to
determine whether a particular privilege is granted in the check routine,
rather than relying on hints from the calling context via the
SUSER_ALLOWJAIL flag. For now, the flag is maintained, but a new jail
check function, prison_priv_check(), is exposed from kern_jail.c and used
by the privilege check routine to determine if the privilege is permitted
in jail. As a result, a centralized list of privileges permitted in jail
is now present in kern_jail.c.
The MAC Framework is now also able to instrument privilege checks, both
to deny privileges otherwise granted (mac_priv_check()), and to grant
privileges otherwise denied (mac_priv_grant()), permitting MAC Policy
modules to implement privilege models, as well as control a much broader
range of system behavior in order to constrain processes running with
root privilege.
The suser() and suser_cred() functions remain implemented, now in terms
of priv_check() and the PRIV_ROOT privilege, for use during the transition
and possibly continuing use by third party kernel modules that have not
been updated. The PRIV_DRIVER privilege exists to allow device drivers to
check privilege without adopting a more specific privilege identifier.
This change does not modify the actual security policy, rather, it
modifies the interface for privilege checks so changes to the security
policy become more feasible.
Sponsored by: nCircle Network Security, Inc.
Obtained from: TrustedBSD Project
Discussed on: arch@
Reviewed (at least in part) by: mlaier, jmg, pjd, bde, ceri,
Alex Lyashkov <umka at sevcity dot net>,
Skip Ford <skip dot ford at verizon dot net>,
Antoine Brodin <antoine dot brodin at laposte dot net>
sockaddr_storage. This structure is defined in RFC 2553 and is a more
semantically correct structure for holding IP and IP6 sockaddr information.
struct sockaddr is not big enough to hold all the required information for
IP6, resulting in truncated addresses et al when auditing IP6 sockaddr
information.
We also need to assume that the sa->sa_len has been validated before the call to
audit_arg_sockaddr() is made, otherwise it could result in a buffer overflow.
This is being done to accommodate auditing of network related arguments (like
connect, bind et al) that will be added soon.
Discussed with: rwatson
Obtained from: TrustedBSD Project
MFC after: 2 weeks
begun with a repo-copy of mac.h to mac_framework.h. sys/mac.h now
contains the userspace and user<->kernel API and definitions, with all
in-kernel interfaces moved to mac_framework.h, which is now included
across most of the kernel instead.
This change is the first step in a larger cleanup and sweep of MAC
Framework interfaces in the kernel, and will not be MFC'd.
Obtained from: TrustedBSD Project
Sponsored by: SPARTA
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
other problems while labels were first being added to various kernel
objects. They have outlived their usefulness.
MFC after: 1 month
Suggested by: Christopher dot Vance at SPARTA dot com
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
with other commonly used sysctl name spaces, rather than declaring them
all over the place.
MFC after: 1 month
Sponsored by: nCircle Network Security, Inc.
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
exists to allow the mandatory access control policy to properly initialize
mbufs generated by the firewall. An example where this might happen is keep
alive packets, or ICMP error packets in response to other packets.
This takes care of kernel panics associated with un-initialize mbuf labels
when the firewall generates packets.
[1] I modified this patch from it's original version, the initial patch
introduced a number of entry points which were programmatically
equivalent. So I introduced only one. Instead, we should leverage
mac_create_mbuf_netlayer() which is used for similar situations,
an example being icmp_error()
This will minimize the impact associated with the MFC
Submitted by: mlaier [1]
MFC after: 1 week
This is a RELENG_6 candidate
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)
is loaded. This problem stems from the fact that the policy is not properly
initializing the mac label associated with the NFS daemon.
Obtained from: TrustedBSD Project
Discussed with: rwatson
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
we will initialize the label to biba/low for files that have been created
through an NFS RPC. This is a safe default given the default nature of our
NFS implementation, there is not a whole lot of data integrity there by
default. This also fixes kernel panics associated with file creation over NFS
while creating files on filesystems which have multilabel enabled with BIBA
enabled.
MFC after: 2 weeks
Discussed with: rwatson
- 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
