The current approach of injecting manifest into mac_veriexec is to
verify the integrity of it in userspace (veriexec (8)) and pass its
entries into kernel using a char device (/dev/veriexec).
This requires verifying root partition integrity in loader,
for example by using memory disk and checking its hash.
Otherwise if rootfs is compromised an attacker could inject their own data.
This patch introduces an option to parse manifest in kernel based on envs.
The loader sets manifest path and digest.
EVENTHANDLER is used to launch the module right after the rootfs is mounted.
It has to be done this way, since one might want to verify integrity of the init file.
This means that manifest is required to be present on the root partition.
Note that the envs have to be set right before boot to make sure that no one can spoof them.
Submitted by: Kornel Duleba <mindal@semihalf.com>
Reviewed by: sjg
Obtained from: Semihalf
Sponsored by: Stormshield
Differential Revision: https://reviews.freebsd.org/D19281
An integrity check such as a check-hash or a cross-correlation failed.
The integrity error falls between EINVAL that identifies errors in
parameters to a system call and EIO that identifies errors with the
underlying storage media. EINTEGRITY is typically raised by intermediate
kernel layers such as a filesystem or an in-kernel GEOM subsystem when
they detect inconsistencies. Uses include allowing the mount(8) command
to return a different exit value to automate the running of fsck(8)
during a system boot.
These changes make no use of the new error, they just add it. Later
commits will be made for the use of the new error number and it will
be added to additional manual pages as appropriate.
Reviewed by: gnn, dim, brueffer, imp
Discussed with: kib, cem, emaste, ed, jilles
Differential Revision: https://reviews.freebsd.org/D18765
Prior to the change the code would branch on return value and then check
if probes are enabled. Since vast majority of the time they are not, this
is clearly wasteful. Check probes first.
Sponsored by: The FreeBSD Foundation
These arguments are mostly paths handled by NAMEI*() macros which already
take const char * arguments.
This change improves the match between syscalls.master and the public
declerations of system calls.
Reviewed by: kib (prior version)
Obtained from: CheriBSD
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D17812
system-call entry and whenever audit arguments or return values are
captured:
1. Expose a single global, audit_syscalls_enabled, which controls
whether the audit framework is entered, rather than exposing
components of the policy -- e.g., if the trail is enabled,
suspended, etc.
2. Introduce a new function audit_syscalls_enabled_update(), which is
called to update audit_syscalls_enabled whenever an aspect of the
policy changes, so that the value can be updated.
3. Remove a check of trail enablement/suspension from audit_new() --
at the point where this function has been entered, we believe that
system-call auditing is already in force, or we wouldn't get here,
so simply proceed to more expensive policy checks.
4. Use an audit-provided global, audit_dtrace_enabled, rather than a
dtaudit-provided global, to provide policy indicating whether
dtaudit would like system calls to be audited.
5. Do some minor cosmetic renaming to clarify what various variables
are for.
These changes collectively arrange it so that traditional audit
(trail, pipes) or the DTrace audit provider can enable system-call
probes without the other configured. Otherwise, dtaudit cannot
capture system-call data without auditd(8) started.
Reviewed by: gnn
Sponsored by: DARPA, AFRL
Approved by: re (gjb)
Differential Revision: https://reviews.freebsd.org/D17348
/etc/security/audit_event to provide a list of audit event-number <->
name mappings. However, this occurs too late for anonymous tracing.
With this change, adding 'audit_event_load="YES"' to /boot/loader.conf
will cause the boot loader to preload the file, and then the kernel
audit code will parse it to register an initial set of audit event-number
<-> name mappings. Those mappings can later be updated by auditd(8) if
the configuration file changes.
Reviewed by: gnn, asomers, markj, allanjude
Discussed with: jhb
Approved by: re (kib)
MFC after: 1 week
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D16589
The buffer size may be used to initialize an sbuf in
MAC_POLICY_EXTERNALIZE, and without this constraint it's possible to
trigger an assertion failure in the sbuf code. With INVARIANTS
disabled, the first attempt to write to the sbuf will fail.
Reported by: pho
Reviewed by: delphij
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D16527
These syscalls were always supposed to have been auditted, but due to
oversights never were.
PR: 228374
Reported by: aniketp
Reviewed by: aniketp
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D16388
Code analysis and runtime analysis using truss(8) indicate that the only
privileged operations performed by ntpd are adjusting system time, and
(re-)binding to privileged UDP port 123. These changes add a new mac(4)
policy module, mac_ntpd(4), which grants just those privileges to any
process running with uid 123.
This also adds a new user and group, ntpd:ntpd, (uid:gid 123:123), and makes
them the owner of the /var/db/ntp directory, so that it can be used as a
location where the non-privileged daemon can write files such as the
driftfile, and any optional logfile or stats files.
Because there are so many ways to configure ntpd, the question of how to
configure it to run without root privs can be a bit complex, so that will be
addressed in a separate commit. These changes are just what's required to
grant the limited subset of privs to ntpd, and the small change to ntpd to
prevent it from exiting with an error if running as non-root.
Differential Revision: https://reviews.freebsd.org/D16281
A_SETPOLICY is supposed to work with either 64 or 32-bit values, but due to a
typo the 64-bit version has never worked correctly.
Submitted by: aniketp
Reviewed by: asomers, cem
MFC after: 2 weeks
Sponsored by: Google, Inc. (GSoC 2018)
Differential Revision: https://reviews.freebsd.org/D16222
fsid_t and ino_t are 64-bit entities, use uintmax_t typecast to ensure we
can print it on 32-bit or 64-bit architectures by using the %ju format for
prints.
Obtained from: Juniper Networks, Inc.
framework.
The code is organized into a few distinct pieces:
* The meta-data store (in veriexec_metadata.c) which maps a file system
identifier, file identifier, and generation key tuple to veriexec
meta-data record.
* Fingerprint management (in veriexec_fingerprint.c) which deals with
calculating the cryptographic hash for a file and verifying it. It also
manages the loadable fingerprint modules.
* MAC policy implementation (in mac_veriexec.c) which implements the
following MAC methods:
mpo_init
Initializes the veriexec state, meta-data store, fingerprint modules,
and registers mount and unmount EVENTHANDLERs
mpo_syscall
Implements the following per-policy system calls:
MAC_VERIEXEC_CHECK_FD_SYSCALL
Check a file descriptor to see if the referenced file has a valid
fingerprint.
MAC_VERIEXEC_CHECK_PATH_SYSCALL
Check a path to see if the referenced file has a valid fingerprint.
mpo_kld_check_load
Check if loading a kld is allowed. This checks if the referenced vnode
has a valid fingerprint.
mpo_mount_destroy_label
Clears the veriexec slot data in a mount point label.
mpo_mount_init_label
Initializes the veriexec slot data in a mount point label.
The file system identifier is saved in the veriexec slot data.
mpo_priv_check
Check if a process is allowed to write to /dev/kmem and /dev/mem
devices.
If a process is flagged as trusted, it is allowed to write.
mpo_proc_check_debug
Check if a process is allowed to be debugged. If a process is not
flagged with VERIEXEC_NOTRACE, then debugging is allowed.
mpo_vnode_check_exec
Check is an exectuable is allowed to run. If veriexec is not enforcing
or the executable has a valid fingerprint, then it is allowed to run.
NOTE: veriexec will complain about mismatched fingerprints if it is
active, regardless of the state of the enforcement.
mpo_vnode_check_open
Check is a file is allowed to be opened. If verification was not
requested, veriexec is not enforcing, or the file has a valid
fingerprint, then veriexec will allow the file to be opened.
mpo_vnode_copy_label
Copies the veriexec slot data from one label to another.
mpo_vnode_destroy_label
Clears the veriexec slot data in a vnode label.
mpo_vnode_init_label
Initializes the veriexec slot data in a vnode label.
The fingerprint status for the file is stored in the veriexec slot data.
* Some sysctls, under security.mac.veriexec, for setting debug level,
fetching the current state in a human-readable form, and dumping the
fingerprint database are implemented.
* The MAC policy implementation source file also contains some utility
functions.
* A set of fingerprint modules for the following cryptographic hash
algorithms:
RIPEMD-160, SHA1, SHA2-256, SHA2-384, SHA2-512
* Loadable module builds for MAC/veriexec and fingerprint modules.
WARNING: Using veriexec with NFS (or other network-based) file systems is
not recommended as one cannot guarantee the integrity of the files
served, nor the uniqueness of file system identifiers which are
used as key in the meta-data store.
Reviewed by: ian, jtl
Obtained from: Juniper Networks, Inc.
Differential Revision: https://reviews.freebsd.org/D8554
Due to a copy/paste error in r168688, ARG_TERMID_ADDR has the same
definition as ARG_SADDRUNIX. Fix it.
The header change, while publicly visible, is guarded by #ifdef KERNEL, and
I can't find any kmod ports that use it. So I'm not bumping
__FreeBSD_version.
PR: 228820
Submitted by: aniketp
Sponsored by: Google, Inc. (GSoC 2018)
Differential Revision: https://reviews.freebsd.org/D15702
security/audit/audit_ioctl.h uses a type from bsm/audit.h, so needs to
include it. And it needs to know the type's size, so it can't just
forward-declare.
PR: 228470
Submitted by: aniketp
MFC after: 2 weeks
Sponsored by: Google, Inc. (GSoC 2018)
Differential Revision: https://reviews.freebsd.org/D15561
Due to an oversight in r195280, auditon(A_SETCLASS, ...) would cause a tailq
element to get added to the tailq twice, resulting in a circular tailq. This
panics when INVARIANTS are on.
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D15381
This fixes 32-bit compat (no ioctl command defintions are required
as struct ifreq is the same size). This is believed to be sufficent to
fully support ifconfig on 32-bit systems.
Reviewed by: kib
Obtained from: CheriBSD
MFC after: 1 week
Relnotes: yes
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D14900
This reduces noise when kernel is compiled by newer GCC versions,
such as one used by external toolchain ports.
Reviewed by: kib, andrew(sys/arm and sys/arm64), emaste(partial), erj(partial)
Reviewed by: jhb (sys/dev/pci/* sys/kern/vfs_aio.c and sys/kern/kern_synch.c)
Differential Revision: https://reviews.freebsd.org/D10385
Mainly focus on files that use BSD 3-Clause license.
The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.
Extend the ino_t, dev_t, nlink_t types to 64-bit ints. Modify
struct dirent layout to add d_off, increase the size of d_fileno
to 64-bits, increase the size of d_namlen to 16-bits, and change
the required alignment. Increase struct statfs f_mntfromname[] and
f_mntonname[] array length MNAMELEN to 1024.
ABI breakage is mitigated by providing compatibility using versioned
symbols, ingenious use of the existing padding in structures, and
by employing other tricks. Unfortunately, not everything can be
fixed, especially outside the base system. For instance, third-party
APIs which pass struct stat around are broken in backward and
forward incompatible ways.
Kinfo sysctl MIBs ABI is changed in backward-compatible way, but
there is no general mechanism to handle other sysctl MIBS which
return structures where the layout has changed. It was considered
that the breakage is either in the management interfaces, where we
usually allow ABI slip, or is not important.
Struct xvnode changed layout, no compat shims are provided.
For struct xtty, dev_t tty device member was reduced to uint32_t.
It was decided that keeping ABI compat in this case is more useful
than reporting 64-bit dev_t, for the sake of pstat.
Update note: strictly follow the instructions in UPDATING. Build
and install the new kernel with COMPAT_FREEBSD11 option enabled,
then reboot, and only then install new world.
Credits: The 64-bit inode project, also known as ino64, started life
many years ago as a project by Gleb Kurtsou (gleb). Kirk McKusick
(mckusick) then picked up and updated the patch, and acted as a
flag-waver. Feedback, suggestions, and discussions were carried
by Ed Maste (emaste), John Baldwin (jhb), Jilles Tjoelker (jilles),
and Rick Macklem (rmacklem). Kris Moore (kris) performed an initial
ports investigation followed by an exp-run by Antoine Brodin (antoine).
Essential and all-embracing testing was done by Peter Holm (pho).
The heavy lifting of coordinating all these efforts and bringing the
project to completion were done by Konstantin Belousov (kib).
Sponsored by: The FreeBSD Foundation (emaste, kib)
Differential revision: https://reviews.freebsd.org/D10439
retaining various utility functions used during BSM generation,
and a second (audit_bsm_db.c) that contains the various in-kernel
databases supporting various audit activities (the class and
event-name tables).
(No functional change is intended.)
Obtained from: TrustedBSD Project
MFC after: 3 weeks
Sponsored by: DARPA, AFRL
This requires minor changes to the audit framework to allow capturing
paths that are not filesystem paths (i.e., will not be canonicalised
relative to the process current working directory and/or filesystem
root).
Obtained from: TrustedBSD Project
MFC after: 3 weeks
Sponsored by: DARPA, AFRL
AUE_PROCCTL, AUE_SENDFILE, AUE_ACL_*, and AUE_POSIX_FALLOCATE.
Audit AUE_SHMUNLINK path in the path token rather than as a
text string, and AUE_SHMOPEN flags as an integer token rather
than a System V IPC address token.
Obtained from: TrustedBSD Project
MFC after: 3 weeks
Sponsored by: DARPA, AFRL
definitions for the DTrace audit provider, so that the dtaudit module
can compile in the absence of kernel DTrace support. This doesn't
really make run-time sense (since the binary dependencies for the
module won't be present), but it allows the dtaudit module to compile
successfully regardless of the kernel configuration.
MFC after: 3 weeks
Sponsored by: DARPA, AFRL
Reported by: kib
map the 'which' argument into a suitable audit event identifier for the
specific operation requested.
Obtained from: TrustedBSD Project
MFC after: 3 weeks
Sponsored by: DARPA, AFRL
instrument security event auditing rather than relying on conventional BSM
trail files or audit pipes:
- Add a set of per-event 'commit' probes, which provide access to
particular auditable events at the time of commit in system-call return.
These probes gain access to audit data via the in-kernel audit_record
data structure, providing convenient access to system-call arguments and
return values in a single probe.
- Add a set of per-event 'bsm' probes, which provide access to particular
auditable events at the time of BSM record generation in the audit
worker thread. These probes have access to the in-kernel audit_record
data structure and BSM representation as would be written to a trail
file or audit pipe -- i.e., asynchronously in the audit worker thread.
DTrace probe arguments consist of the name of the audit event (to support
future mechanisms of instrumenting multiple events via a single probe --
e.g., using classes), a pointer to the in-kernel audit record, and an
optional pointer to the BSM data and its length. For human convenience,
upper-case audit event names (AUE_...) are converted to lower case in
DTrace.
DTrace scripts can now cause additional audit-based data to be collected
on system calls, and inspect internal and BSM representations of the data.
They do not affect data captured in the audit trail or audit pipes
configured in the system. auditd(8) must be configured and running in
order to provide a database of event information, as well as other audit
configuration parameters (e.g., to capture command-line arguments or
environmental variables) for the provider to operate.
Reviewed by: gnn, jonathan, markj
Sponsored by: DARPA, AFRL
MFC after: 3 weeks
Differential Revision: https://reviews.freebsd.org/D10149
database in the kernel audit implementation, similar the exist
class mapping database. This will be used by the DTrace audit
provider to map audit event identifiers originating in the
system-call table back into strings for the purposes of setting
probe names. The database is initialised and maintained by
auditd(8), which reads values in from the audit_events
configuration file, and then manages them using the A_GETEVENT
and A_SETEVENT auditon(2) operations.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, AFRL
MFC after: 3 weeks
always audit the file-descriptor number and vnode information for all
fnctl(2) commands, not just locking-related ones. This was likely an
oversight in the original adaptation of this code from XNU.
MFC after: 3 days
Sponsored by: DARPA, AFRL
(NB: This was likely a mismerge from XNU in audit support, where the
text argument to setlogin(2) is captured -- but as a text token,
whereas this change uses the dedicated login-name field in struct
audit_record.)
MFC after: 2 weeks
Sponsored by: DARPA, AFRL
console warnings when pread(2) and pwrite(2) are used with full
system-call auditing enabled. We audit the same file-descriptor data
for these calls as we do read(2) and write(2).
Approved by: re (kib)
MFC after: 3 days
Sponsored by: DARPA, AFRL
