Commit Graph

292 Commits

Author SHA1 Message Date
Ed Maste
532bc58628 pf: zero output buffer in pfioctl
Avoid potential structure padding leak.

Reported by:	Vlad Tsyrklevich <vlad@tsyrklevich.net>
Reviewed by:	kp
MFC after:	3 days
Security:	Potential kernel memory disclosure
Sponsored by:	The FreeBSD Foundation
2019-07-24 16:51:14 +00:00
Hans Petter Selasky
59854ecf55 Convert all IPv4 and IPv6 multicast memberships into using a STAILQ
instead of a linear array.

The multicast memberships for the inpcb structure are protected by a
non-sleepable lock, INP_WLOCK(), which needs to be dropped when
calling the underlying possibly sleeping if_ioctl() method. When using
a linear array to keep track of multicast memberships, the computed
memory location of the multicast filter may suddenly change, due to
concurrent insertion or removal of elements in the linear array. This
in turn leads to various invalid memory access issues and kernel
panics.

To avoid this problem, put all multicast memberships on a STAILQ based
list. Then the memory location of the IPv4 and IPv6 multicast filters
become fixed during their lifetime and use after free and memory leak
issues are easier to track, for example by: vmstat -m | grep multi

All list manipulation has been factored into inline functions
including some macros, to easily allow for a future hash-list
implementation, if needed.

This patch has been tested by pho@ .

Differential Revision: https://reviews.freebsd.org/D20080
Reviewed by:	markj @
MFC after:	1 week
Sponsored by:	Mellanox Technologies
2019-06-25 11:54:41 +00:00
Xin LI
f89d207279 Separate kernel crc32() implementation to its own header (gsb_crc32.h) and
rename the source to gsb_crc32.c.

This is a prerequisite of unifying kernel zlib instances.

PR:		229763
Submitted by:	Yoshihiro Ota <ota at j.email.ne.jp>
Differential Revision:	https://reviews.freebsd.org/D20193
2019-06-17 19:49:08 +00:00
Li-Wen Hsu
d086d41363 Remove an uneeded indentation introduced in r223637 to silence gcc warnging
MFC after:	3 days
Sponsored by:	The FreeBSD Foundation
2019-05-25 23:58:09 +00:00
Kristof Provost
1c75b9d2cd pf: No need to M_NOWAIT in DIOCRSETTFLAGS
Now that we don't hold a lock during DIOCRSETTFLAGS memory allocation we can
use M_WAITOK.

MFC after:	1 week
Event:		Aberdeen hackathon 2019
Pointed out by:	glebius@
2019-04-18 11:37:44 +00:00
Kristof Provost
f5e0d9fcb4 pf: Fix panic on invalid DIOCRSETTFLAGS
If during DIOCRSETTFLAGS pfrio_buffer is NULL copyin() will fault, which we're
not allowed to do with a lock held.
We must count the number of entries in the table and release the lock during
copyin(). Only then can we re-acquire the lock. Note that this is safe, because
pfr_set_tflags() will check if the table and entries exist.

This was discovered by a local syzcaller instance.

MFC after:	1 week
Event:		Aberdeen hackathon 2019
2019-04-17 16:42:54 +00:00
Rodney W. Grimes
6c1c6ae537 Use IN_foo() macros from sys/netinet/in.h inplace of handcrafted code
There are a few places that use hand crafted versions of the macros
from sys/netinet/in.h making it difficult to actually alter the
values in use by these macros.  Correct that by replacing handcrafted
code with proper macro usage.

Reviewed by:		karels, kristof
Approved by:		bde (mentor)
MFC after:		3 weeks
Sponsored by:		John Gilmore
Differential Revision:	https://reviews.freebsd.org/D19317
2019-04-04 19:01:13 +00:00
Conrad Meyer
a8a16c7128 Replace read_random(9) with more appropriate arc4rand(9) KPIs
Reviewed by:	ae, delphij
Sponsored by:	Dell EMC Isilon
Differential Revision:	https://reviews.freebsd.org/D19760
2019-04-04 01:02:50 +00:00
Ed Maste
a342f5772f pf: use UID_ROOT and GID_WHEEL named constants in make_dev
No functional change but improves consistency and greppability of
make_dev calls.

Discussed with: kp
2019-03-26 21:20:42 +00:00
Kristof Provost
64af73aade pf: Ensure that IP addresses match in ICMP error packets
States in pf(4) let ICMP and ICMP6 packets pass if they have a
packet in their payload that matches an exiting connection.  It was
not checked whether the outer ICMP packet has the same destination
IP as the source IP of the inner protocol packet.  Enforce that
these addresses match, to prevent ICMP packets that do not make
sense.

Reported by:	Nicolas Collignon, Corentin Bayet, Eloi Vanderbeken, Luca Moro at Synacktiv
Obtained from:	OpenBSD
Security:	CVE-2019-5598
2019-03-21 08:09:52 +00:00
Kristof Provost
812483c46e pf: Rename pfsync bucket lock
Previously the main pfsync lock and the bucket locks shared the same name.
This lead to spurious warnings from WITNESS like this:

    acquiring duplicate lock of same type: "pfsync"
     1st pfsync @ /usr/src/sys/netpfil/pf/if_pfsync.c:1402
     2nd pfsync @ /usr/src/sys/netpfil/pf/if_pfsync.c:1429

It's perfectly okay to grab both the main pfsync lock and a bucket lock at the
same time.

We don't need different names for each bucket lock, because we should always
only acquire a single one of those at a time.

MFC after:	1 week
2019-03-16 10:14:03 +00:00
Kristof Provost
5904868691 pf :Use counter(9) in pf tables.
The counters of pf tables are updated outside the rule lock. That means state
updates might overwrite each other. Furthermore allocation and
freeing of counters happens outside the lock as well.

Use counter(9) for the counters, and always allocate the counter table
element, so that the race condition cannot happen any more.

PR:		230619
Submitted by:	Kajetan Staszkiewicz <vegeta@tuxpowered.net>
Reviewed by:	glebius
MFC after:	2 weeks
Differential Revision:	https://reviews.freebsd.org/D19558
2019-03-15 11:08:44 +00:00
Gleb Smirnoff
1830dae3d3 Make second argument of ip_divert(), that specifies packet direction a bool.
This allows pf(4) to avoid including ipfw(4) private files.
2019-03-14 22:23:09 +00:00
Kristof Provost
f8e7fe32a4 pf: Fix DIOCGETSRCNODES
r343295 broke DIOCGETSRCNODES by failing to reset 'nr' after counting the
number of source tracking nodes.
This meant that we never copied the information to userspace, leading to '? ->
?' output from pfctl.

PR:		236368
MFC after:	1 week
2019-03-08 09:33:16 +00:00
Kristof Provost
6f4909de5f pf: IPv6 fragments with malformed extension headers could be erroneously passed by pf or cause a panic
We mistakenly used the extoff value from the last packet to patch the
next_header field. If a malicious host sends a chain of fragmented packets
where the first packet and the final packet have different lengths or number of
extension headers we'd patch the next_header at the wrong offset.
This can potentially lead to panics or rule bypasses.

Security:       CVE-2019-5597
Obtained from:  OpenBSD
Reported by:    Corentin Bayet, Nicolas Collignon, Luca Moro at Synacktiv
2019-03-01 07:37:45 +00:00
Kristof Provost
22c58991e3 pf: Small performance tweak
Because fetching a counter is a rather expansive function we should use
counter_u64_fetch() in pf_state_expires() only when necessary. A "rdr
pass" rule should not cause more effort than separate "rdr" and "pass"
rules. For rules with adaptive timeout values the call of
counter_u64_fetch() should be accepted, but otherwise not.

From the man page:
    The adaptive timeout values can be defined both globally and for
    each rule.  When used on a per-rule basis, the values relate to the
    number of states created by the rule, otherwise to the total number
    of states.

This handling of adaptive timeouts is done in pf_state_expires().  The
calculation needs three values: start, end and states.

1. Normal rules "pass .." without adaptive setting meaning "start = 0"
   runs in the else-section and therefore takes "start" and "end" from
   the global default settings and sets "states" to pf_status.states
   (= total number of states).

2. Special rules like
   "pass .. keep state (adaptive.start 500 adaptive.end 1000)"
   have start != 0, run in the if-section and take "start" and "end"
   from the rule and set "states" to the number of states created by
   their rule using counter_u64_fetch().

Thats all ok, but there is a third case without special handling in the
above code snippet:

3. All "rdr/nat pass .." statements use together the pf_default_rule.
   Therefore we have "start != 0" in this case and we run the
   if-section but we better should run the else-section in this case and
   do not fetch the counter of the pf_default_rule but take the total
   number of states.

Submitted by:	Andreas Longwitz <longwitz@incore.de>
MFC after:	2 weeks
2019-02-24 17:23:55 +00:00
Patrick Kelsey
d178fee632 Place pf_altq_get_nth_active() under the ALTQ ifdef
MFC after:	1 week
2019-02-11 05:39:38 +00:00
Patrick Kelsey
8f2ac65690 Reduce the time it takes the kernel to install a new PF config containing a large number of queues
In general, the time savings come from separating the active and
inactive queues lists into separate interface and non-interface queue
lists, and changing the rule and queue tag management from list-based
to hash-bashed.

In HFSC, a linear scan of the class table during each queue destroy
was also eliminated.

There are now two new tunables to control the hash size used for each
tag set (default for each is 128):

net.pf.queue_tag_hashsize
net.pf.rule_tag_hashsize

Reviewed by:	kp
MFC after:	1 week
Sponsored by:	RG Nets
Differential Revision:	https://reviews.freebsd.org/D19131
2019-02-11 05:17:31 +00:00
Gleb Smirnoff
d38ca3297c Return PFIL_CONSUMED if packet was consumed. While here gather all
the identical endings of pf_check_*() into single function.

PR:		235411
2019-02-02 05:49:05 +00:00
Gleb Smirnoff
b252313f0b New pfil(9) KPI together with newborn pfil API and control utility.
The KPI have been reviewed and cleansed of features that were planned
back 20 years ago and never implemented.  The pfil(9) internals have
been made opaque to protocols with only returned types and function
declarations exposed. The KPI is made more strict, but at the same time
more extensible, as kernel uses same command structures that userland
ioctl uses.

In nutshell [KA]PI is about declaring filtering points, declaring
filters and linking and unlinking them together.

New [KA]PI makes it possible to reconfigure pfil(9) configuration:
change order of hooks, rehook filter from one filtering point to a
different one, disconnect a hook on output leaving it on input only,
prepend/append a filter to existing list of filters.

Now it possible for a single packet filter to provide multiple rulesets
that may be linked to different points. Think of per-interface ACLs in
Cisco or Juniper. None of existing packet filters yet support that,
however limited usage is already possible, e.g. default ruleset can
be moved to single interface, as soon as interface would pride their
filtering points.

Another future feature is possiblity to create pfil heads, that provide
not an mbuf pointer but just a memory pointer with length. That would
allow filtering at very early stages of a packet lifecycle, e.g. when
packet has just been received by a NIC and no mbuf was yet allocated.

Differential Revision:	https://reviews.freebsd.org/D18951
2019-01-31 23:01:03 +00:00
Patrick Kelsey
59099cd385 Don't re-evaluate ALTQ kernel configuration due to events on non-ALTQ interfaces
Re-evaluating the ALTQ kernel configuration can be expensive,
particularly when there are a large number (hundreds or thousands) of
queues, and is wholly unnecessary in response to events on interfaces
that do not support ALTQ as such interfaces cannot be part of an ALTQ
configuration.

Reviewed by:	kp
MFC after:	1 week
Sponsored by:	RG Nets
Differential Revision:	https://reviews.freebsd.org/D18918
2019-01-28 20:26:09 +00:00
Kristof Provost
d9d146e67b pf: Fix use-after-free of counters
When cleaning up a vnet we free the counters in V_pf_default_rule and
V_pf_status from shutdown_pf(), but we can still use them later, for example
through pf_purge_expired_src_nodes().

Free them as the very last operation, as they rely on nothing else themselves.

PR:		235097
MFC after:	1 week
2019-01-25 01:06:06 +00:00
Kristof Provost
180b0dcbbb pf: Validate psn_len in DIOCGETSRCNODES
psn_len is controlled by user space, but we allocated memory based on it.
Check how much memory we might need at most (i.e. how many source nodes we
have) and limit the allocation to that.

Reported by:	markj
MFC after:	1 week
2019-01-22 02:13:33 +00:00
Kristof Provost
6a8ee0f715 pf: fix pfsync breaking carp
Fix missing initialisation of sc_flags into a valid sync state on clone which
breaks carp in pfsync.

This regression was introduce by r342051.

PR:		235005
Submitted by:	smh@FreeBSD.org
Pointy hat to:	kp
MFC after:	3 days
Differential Revision:	https://reviews.freebsd.org/D18882
2019-01-18 08:19:54 +00:00
Kristof Provost
032dff662c pf: silence a runtime warning
Sometimes, for negated tables, pf can log 'pfr_update_stats: assertion failed'.
This warning does not clarify anything for users, so silence it, just as
OpenBSD has.

PR:		234874
MFC after:	1 week
2019-01-15 08:59:51 +00:00
Gleb Smirnoff
a68cc38879 Mechanical cleanup of epoch(9) usage in network stack.
- Remove macros that covertly create epoch_tracker on thread stack. Such
  macros a quite unsafe, e.g. will produce a buggy code if same macro is
  used in embedded scopes. Explicitly declare epoch_tracker always.

- Unmask interface list IFNET_RLOCK_NOSLEEP(), interface address list
  IF_ADDR_RLOCK() and interface AF specific data IF_AFDATA_RLOCK() read
  locking macros to what they actually are - the net_epoch.
  Keeping them as is is very misleading. They all are named FOO_RLOCK(),
  while they no longer have lock semantics. Now they allow recursion and
  what's more important they now no longer guarantee protection against
  their companion WLOCK macros.
  Note: INP_HASH_RLOCK() has same problems, but not touched by this commit.

This is non functional mechanical change. The only functionally changed
functions are ni6_addrs() and ni6_store_addrs(), where we no longer enter
epoch recursively.

Discussed with:	jtl, gallatin
2019-01-09 01:11:19 +00:00
Kristof Provost
336683f24f pf: Fix endless loop on NAT exhaustion with sticky-address
When we try to find a source port in pf_get_sport() it's possible that
all available source ports will be in use. In that case we call
pf_map_addr() to try to find a new source IP to try from. If there are
no more available source IPs pf_map_addr() will return 1 and we stop
trying.

However, if sticky-address is set we'll always return the same IP
address, even if we've already tried that one.
We need to check the supplied address, because if that's the one we'd
set it means pf_get_sport() has already tried it, and we should error
out rather than keep trying.

PR:		233867
MFC after:	2 weeks
Differential Revision:	https://reviews.freebsd.org/D18483
2018-12-12 20:15:06 +00:00
Kristof Provost
5b551954ab pf: Prevent integer overflow in PF when calculating the adaptive timeout.
Mainly states of established TCP connections would be affected resulting
in immediate state removal once the number of states is bigger than
adaptive.start.  Disabling adaptive timeouts is a workaround to avoid this bug.
Issue found and initial diff by Mathieu Blanc (mathieu.blanc at cea dot fr)

Reported by: Andreas Longwitz <longwitz AT incore.de>
Obtained from:  OpenBSD
MFC after:	2 weeks
2018-12-11 21:44:39 +00:00
Kristof Provost
4fc65bcbe3 pfsync: Performance improvement
pfsync code is called for every new state, state update and state
deletion in pf. While pf itself can operate on multiple states at the
same time (on different cores, assuming the states hash to a different
hashrow), pfsync only had a single lock.
This greatly reduced throughput on multicore systems.

Address this by splitting the pfsync queues into buckets, based on the
state id. This ensures that updates for a given connection always end up
in the same bucket, which allows pfsync to still collapse multiple
updates into one, while allowing multiple cores to proceed at the same
time.

The number of buckets is tunable, but defaults to 2 x number of cpus.
Benchmarking has shown improvement, depending on hardware and setup, from ~30%
to ~100%.

MFC after:	1 week
Sponsored by:	Orange Business Services
Differential Revision:	https://reviews.freebsd.org/D18373
2018-12-06 19:27:15 +00:00
Kristof Provost
2b0a4ffadb pf: add a comment describing why do we call pf_map_addr again if port
selection process fails

Obtained from:	OpenBSD
2018-12-06 18:58:54 +00:00
Kristof Provost
b2e0b24f76 pf: Fix panic on overlapping interface names
In rare situations[*] it's possible for two different interfaces to have
the same name. This confuses pf, because kifs are indexed by name (which
is assumed to be unique). As a result we can end up trying to
if_rele(NULL), which panics.

Explicitly checking the ifp pointer before if_rele() prevents the panic.
Note pf will likely behave in unexpected ways on the the overlapping
interfaces.

[*] Insert an interface in a vnet jail. Rename it to an interface which
exists on the host. Remove the jail. There are now two interfaces with
the same name in the host.
2018-12-01 09:58:21 +00:00
Kristof Provost
87e4ca37d5 pf: Prevent tables referenced by rules in anchors from getting disabled.
PR:		183198
Obtained from:	OpenBSD
MFC after:	2 weeks
2018-11-08 21:54:40 +00:00
Kristof Provost
58ef854f8b pf: Fix build if INVARIANTS is not set
r340061 included a number of assertions pf_frent_remove(), but these assertions
were the only use of the 'prev' variable. As a result builds without
INVARIANTS had an unused variable, and failed.

Reported by:	vangyzen@
2018-11-02 19:23:50 +00:00
Kristof Provost
14624ab582 pf: Keep a reference to struct ifnets we're using
Ensure that the struct ifnet we use can't go away until we're done with
it.
2018-11-02 17:05:40 +00:00
Kristof Provost
dde6e1fecb pfsync: Add missing unlock
If we fail to set up the multicast entry for pfsync and return an error
we must release the pfsync lock first.

MFC after:	2 weeks
Sponsored by:	Orange Business Services
Differential Revision:	https://reviews.freebsd.org/D17506
2018-11-02 17:03:53 +00:00
Kristof Provost
04fe85f068 pfsync: Allow module to be unloaded
MFC after:	2 weeks
Sponsored by:	Orange Business Services
Differential Revision:	https://reviews.freebsd.org/D17505
2018-11-02 17:01:18 +00:00
Kristof Provost
fbbf436d56 pfsync: Handle syncdev going away
If the syncdev is removed we no longer need to clean up the multicast
entry we've got set up for that device.

Pass the ifnet detach event through pf to pfsync, and remove our
multicast handle, and mark us as no longer having a syncdev.

Note that this callback is always installed, even if the pfsync
interface is disabled (and thus it's not a per-vnet callback pointer).

MFC after:	2 weeks
Sponsored by:	Orange Business Services
Differential Revision:	https://reviews.freebsd.org/D17502
2018-11-02 16:57:23 +00:00
Kristof Provost
26549dfcad pfsync: Ensure uninit is done before pf
pfsync touches pf memory (for pf_state and the pfsync callback
pointers), not the other way around. We need to ensure that pfsync is
torn down before pf.

MFC after:	2 weeks
Sponsored by:	Orange Business Services
Differential Revision:	https://reviews.freebsd.org/D17501
2018-11-02 16:53:15 +00:00
Kristof Provost
5f6cf24e2d pfsync: Make pfsync callbacks per-vnet
The callbacks are installed and removed depending on the state of the
pfsync device, which is per-vnet. The callbacks must also be per-vnet.

MFC after:	2 weeks
Sponsored by:	Orange Business Services
Differential Revision:	https://reviews.freebsd.org/D17499
2018-11-02 16:47:07 +00:00
Kristof Provost
790194cd47 pf: Limit the fragment entry queue length to 64 per bucket.
So we have a global limit of 1024 fragments, but it is fine grained to
the region of the packet.  Smaller packets may have less fragments.
This costs another 16 bytes of memory per reassembly and devides the
worst case for searching by 8.

Obtained from:	OpenBSD
Differential Revision:	https://reviews.freebsd.org/D17734
2018-11-02 15:32:04 +00:00
Kristof Provost
fd2ea405e6 pf: Split the fragment reassembly queue into smaller parts
Remember 16 entry points based on the fragment offset.  Instead of
a worst case of 8196 list traversals we now check a maximum of 512
list entries or 16 array elements.

Obtained from:	OpenBSD
Differential Revision:	https://reviews.freebsd.org/D17733
2018-11-02 15:26:51 +00:00
Kristof Provost
2b1c354ee6 pf: Count holes rather than fragments for reassembly
Avoid traversing the list of fragment entris to check whether the
pf(4) reassembly is complete.  Instead count the holes that are
created when inserting a fragment.  If there are no holes left, the
fragments are continuous.

Obtained from:	OpenBSD
Differential Revision:	https://reviews.freebsd.org/D17732
2018-11-02 15:23:57 +00:00
Kristof Provost
19a22ae313 Revert "pf: Limit the maximum number of fragments per packet"
This reverts commit r337969.
We'll handle this the OpenBSD way, in upcoming commits.
2018-11-02 15:01:59 +00:00
Kristof Provost
99eb00558a pf: Make ':0' ignore link-local v6 addresses too
When users mark an interface to not use aliases they likely also don't
want to use the link-local v6 address there.

PR:		201695
Submitted by:	Russell Yount <Russell.Yount AT gmail.com>
Differential Revision:	https://reviews.freebsd.org/D17633
2018-10-28 05:32:50 +00:00
Kristof Provost
13d640d376 pf: Fix copy/paste error in IPv6 address rewriting
We checked the destination address, but replaced the source address. This was
fixed in OpenBSD as part of their NAT rework, which we don't want to import
right now.

CID:		1009561
MFC after:	3 weeks
2018-10-24 00:19:44 +00:00
Kristof Provost
73c9014569 pf: ifp can never be NULL in pfi_ifaddr_event()
There's no point in the NULL check for ifp, because we'll already have
dereferenced it by then. Moreover, the event will always have a valid ifp.

Replace the late check with an early assertion.

CID:		1357338
2018-10-23 23:15:44 +00:00
Kristof Provost
1563a27e1f pf synproxy will do the 3WHS on behalf of the target machine, and once
the 3WHS is completed, establish the backend connection. The trigger
for "3WHS completed" is the reception of the first ACK. However, we
should not proceed if that ACK also has RST or FIN set.

PR:		197484
Obtained from:	OpenBSD
MFC after:	2 weeks
2018-10-20 18:37:21 +00:00
John-Mark Gurney
032d3aaa96 Significantly improve pf purge cpu usage by only taking locks
when there is work to do.  This reduces CPU consumption to one
third on systems.  This will help keep the thread CPU usage under
control now that the default hash size has increased.

Reviewed by:	kp
Approved by:	re (kib)
Differential Revision:	https://reviews.freebsd.org/D17097
2018-09-16 00:44:23 +00:00
Patrick Kelsey
249cc75fd1 Extended pf(4) ioctl interface and pfctl(8) to allow bandwidths of
2^32 bps or greater to be used.  Prior to this, bandwidth parameters
would simply wrap at the 2^32 boundary.  The computations in the HFSC
scheduler and token bucket regulator have been modified to operate
correctly up to at least 100 Gbps.  No other algorithms have been
examined or modified for correct operation above 2^32 bps (some may
have existing computation resolution or overflow issues at rates below
that threshold).  pfctl(8) will now limit non-HFSC bandwidth
parameters to 2^32 - 1 before passing them to the kernel.

The extensions to the pf(4) ioctl interface have been made in a
backwards-compatible way by versioning affected data structures,
supporting all versions in the kernel, and implementing macros that
will cause existing code that consumes that interface to use version 0
without source modifications.  If version 0 consumers of the interface
are used against a new kernel that has had bandwidth parameters of
2^32 or greater configured by updated tools, such bandwidth parameters
will be reported as 2^32 - 1 bps by those old consumers.

All in-tree consumers of the pf(4) interface have been updated.  To
update out-of-tree consumers to the latest version of the interface,
define PFIOC_USE_LATEST ahead of any includes and use the code of
pfctl(8) as a guide for the ioctls of interest.

PR:	211730
Reviewed by:	jmallett, kp, loos
MFC after:	2 weeks
Relnotes:	yes
Sponsored by:	RG Nets
Differential Revision:	https://reviews.freebsd.org/D16782
2018-08-22 19:38:48 +00:00
Kristof Provost
d47023236c pf: Limit the maximum number of fragments per packet
Similar to the network stack issue fixed in r337782 pf did not limit the number
of fragments per packet, which could be exploited to generate high CPU loads
with a crafted series of packets.

Limit each packet to no more than 64 fragments. This should be sufficient on
typical networks to allow maximum-sized IP frames.

This addresses the issue for both IPv4 and IPv6.

MFC after:	3 days
Security:	CVE-2018-5391
Sponsored by:	Klara Systems
2018-08-17 15:00:10 +00:00