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
The pfil(9) system is about to be converted to epoch(9) synchronization, so
we need [temporarily] go back with ipfw internal locking.
Discussed with: ae
handling for protocols without ports numbers.
Since port numbers were uninitialized for protocols like ICMP/ICMPv6,
ipfw_chk() used some non-zero values to create dynamic states, and due
this it failed to match replies with created states.
Reported by: Oliver Hartmann, Boris Lytochkin
Obtained from: Yandex LLC
X-MFC after: r342908
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
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
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
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
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
CARP shares protocol number 112 with VRRP (RFC 5798). And the size of
VRRP packet may be smaller than CARP. ipfw_chk() does m_pullup() to at
least sizeof(struct carp_header) and can fail when packet is VRRP. This
leads to packet drop and message about failed pullup attempt.
Also, RFC 5798 defines version 3 of VRRP protocol, this version number
also unsupported by CARP and such check leads to packet drop.
carp_input() does its own checks for protocol version and packet size,
so we can remove these checks to be able pass VRRP packets.
PR: 234207
MFC after: 1 week
And refactor the code to avoid unneeded initialization to reduce overhead
of per-packet processing.
ipfw(4) can be invoked by pfil(9) framework for each packet several times.
Each call uses on-stack variable of type struct ip_fw_args to keep the
state of ipfw(4) processing. Currently this variable has 240 bytes size
on amd64. Each time ipfw(4) does bzero() on it, and then it initializes
some fields.
glebius@ has reported that they at Netflix discovered, that initialization
of this variable produces significant overhead on packet processing.
After patching I managed to increase performance of packet processing on
simple routing with ipfw(4) firewalling to about 11% from 9.8Mpps up to
11Mpps (Xeon E5-2660 v4@ + Mellanox 100G card).
Introduced new field flags, it is used to keep track of what fields was
initialized. Some fields were moved into the anonymous union, to reduce
the size. They all are mutually exclusive. dummypar field was unused, and
therefore it is removed. The hopstore6 field type was changed from
sockaddr_in6 to a bit smaller struct ip_fw_nh6. And now the size of struct
ip_fw_args is 128 bytes.
ipfw_chk() was modified to properly handle ip_fw_args.flags instead of
rely on checking for NULL pointers.
Reviewed by: gallatin
Obtained from: Yandex LLC
MFC after: 1 month
Sponsored by: Yandex LLC
Differential Revision: https://reviews.freebsd.org/D18690
- 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
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
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
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
This can be useful, when net.inet.ip.fw.dyn_keep_states is enabled, but
after rules reloading some state must be deleted. Added new flag '-D'
for such purpose.
Retire '-e' flag, since there can not be expired states in the meaning
that this flag historically had.
Also add "verbose" mode for listing of dynamic states, it can be enabled
with '-v' flag and adds additional information to states list. This can
be useful for debugging.
Obtained from: Yandex LLC
MFC after: 2 months
Sponsored by: Yandex LLC
Turning on of this feature allows to keep dynamic states when parent
rule is deleted. But it works only when the default rule is
"allow from any to any".
Now when rule with dynamic opcode is going to be deleted, and
net.inet.ip.fw.dyn_keep_states is enabled, existing states will reference
named objects corresponding to this rule, and also reference the rule.
And when ipfw_dyn_lookup_state() will find state for deleted parent rule,
it will return the pointer to the deleted rule, that is still valid.
This implementation doesn't support O_LIMIT_PARENT rules.
The refcnt field was added to struct ip_fw to keep reference, also
next pointer added to be able iterate rules and not damage the content
when deleted rules are chained.
Named objects are referenced only when states are going to be deleted to
be able reuse kidx of named objects when new parent rules will be
installed.
ipfw_dyn_get_count() function was modified and now it also looks into
dynamic states and constructs maps of existing named objects. This is
needed to correctly export orphaned states into userland.
ipfw_free_rule() was changed to be global, since now dynamic state can
free rule, when it is expired and references counters becomes 1.
External actions subsystem also modified, since external actions can be
deregisterd and instances can be destroyed. In these cases deleted rules,
that are referenced by orphaned states, must be modified to prevent access
to freed memory. ipfw_dyn_reset_eaction(), ipfw_reset_eaction_instance()
functions added for these purposes.
Obtained from: Yandex LLC
MFC after: 2 months
Sponsored by: Yandex LLC
Differential Revision: https://reviews.freebsd.org/D17532
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.
Now an interface name can be specified for nptv6 instance instead of
ext_prefix. The module will track if_addr_ext events and when suitable
IPv6 address will be added to specified interface, it will be configured
as external prefix. When address disappears instance becomes unusable,
i.e. it doesn't match any packets.
Reviewed by: 0mp (manpages)
Tested by: Dries Michiels <driesm dot michiels gmail com>
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D17765
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@
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
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
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
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
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
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
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
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
Kernel part of ipfw does not support and ignores rules other than
"pass", "deny" and dummynet-related for layer-2 (ethernet frames).
Others are processed as "pass".
Make it support ngtee/netgraph rules just like they are supported
for IP packets. For example, this allows us to mirror some frames
selectively to another interface for delivery to remote network analyzer
over RSPAN vlan. Assuming ng_ipfw(4) netgraph node has a hook named "900"
attached to "lower" hook of vlan900's ng_ether(4) node, that would be
as simple as:
ipfw add ngtee 900 ip from any to 8.8.8.8 layer2 out xmit igb0
PR: 213452
MFC after: 1 month
Tested-by: Fyodor Ustinov <ufm@ufm.su>
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
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
This allows use differen values configured by user for sysctl variable
net.inet.ip.fw.dyn_rst_lifetime.
Obtained from: Yandex LLC
MFC after: 3 weeks
Sponsored by: Yandex LLC
to switch the output method in run-time. Also document some sysctl
variables that can by changed for NAT64 module.
NAT64 had compile time option IPFIREWALL_NAT64_DIRECT_OUTPUT to use
if_output directly from nat64 module. By default is used netisr based
output method. Now both methods can be used, but they require different
handling by rules.
Obtained from: Yandex LLC
MFC after: 3 weeks
Sponsored by: Yandex LLC
Differential Revision: https://reviews.freebsd.org/D16647
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
not be used as condition for ternary operator.
Submitted by: Tatsuki Makino <tatsuki_makino at hotmail dot com>
Approved by: re (kib)
MFC after: 1 week
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
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
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
