Forwarded packets passed through PFIL_OUT, which made it difficult for
firewalls to figure out if they were forwarding or producing packets. This in
turn is an issue for pf for IPv6 fragment handling: it needs to call
ip6_output() or ip6_forward() to handle the fragments. Figuring out which was
difficult (and until now, incorrect).
Having pfil distinguish the two removes an ugly piece of code from pf.
Introduce a new variant of the netpfil callbacks with a flags variable, which
has PFIL_FWD set for forwarded packets. This allows pf to reliably work out if
a packet is forwarded.
Reviewed by: ae, kevans
Differential Revision: https://reviews.freebsd.org/D13715
If a user attempts to add two tables with the same name the duplicate table
will not be added, but we forgot to free the duplicate table, leaking memory.
Ensure we free the duplicate table in the error path.
Reported by: Coverity
CID: 1382111
MFC after: 3 weeks
If the user configures a states_hashsize or source_nodes_hashsize value we may
not have enough memory to allocate this. This used to lock up pf, because these
allocations used M_WAITOK.
Cope with this by attempting the allocation with M_NOWAIT and falling back to
the default sizes (with M_WAITOK) if these fail.
PR: 209475
Submitted by: Fehmi Noyan Isi <fnoyanisi AT yahoo.com>
MFC after: 3 weeks
Differential Revision: https://reviews.freebsd.org/D14367
When INVARIANTS is not set the 'last' variable is not used, which can generate
compiler warnings.
If this invariant is ever violated it'd result in a KASSERT failure in
refcount_release(), so this one is not strictly required.
pf_unlink_state() releases a reference to the state without checking if
this is the last reference. It can't be, because pf_state_insert()
initialises it to two. KASSERT() that this is always the case.
CID: 1347140
pfioctl() handles several ioctl that takes variable length input, these
include:
- DIOCRADDTABLES
- DIOCRDELTABLES
- DIOCRGETTABLES
- DIOCRGETTSTATS
- DIOCRCLRTSTATS
- DIOCRSETTFLAGS
All of them take a pfioc_table struct as input from userland. One of
its elements (pfrio_size) is used in a buffer length calculation.
The calculation contains an integer overflow which if triggered can lead
to out of bound reads and writes later on.
Reported by: Ilja Van Sprundel <ivansprundel@ioactive.com>
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.
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.
No functional change intended.
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.
This is an import of Alexander Bluhm's OpenBSD commit r1.60,
the first chunk had to be modified because on OpenBSD the
'cut' declaration is located elsewhere.
Upstream report by Jingmin Zhou:
https://marc.info/?l=openbsd-pf&m=150020133510896&w=2
OpenBSD commit message:
Use a 32 bit variable to detect integer overflow when searching for
an unused nat port. Prevents a possible endless loop if high port
is 65535 or low port is 0.
report and analysis Jingmin Zhou; OK sashan@ visa@
Quoted from: https://cvsweb.openbsd.org/cgi-bin/cvsweb/src/sys/net/pf_lb.c
PR: 221201
Submitted by: Fabian Keil <fk@fabiankeil.de>
Obtained from: OpenBSD via ElectroBSD
MFC after: 1 week
pf_purge_thread() breaks up the work of iterating all states (in
pf_purge_expired_states()) and tracks progress in the idx variable.
If multiple vnets exist this results in pf_purge_thread() only calling
pf_purge_expired_states() for part of the states (the first part of the
first vnet, second part of the second vnet and so on).
Combined with the mark-and-sweep approach to cleaning up old rules (in
V_pf_unlinked_rules) that resulted in pf freeing rules that were still
referenced by states. This in turn caused panics when pf_state_expires()
encounters that state and attempts to access the rule.
We need to track the progress per vnet, not globally, so idx is moved
into a per-vnet V_pf_purge_idx.
PR: 219251
Sponsored by: Hackathon Essen 2017
When running the vnet init code (pf_load_vnet()) we used to iterate over
all vnets, marking them as unhooked.
This is incorrect and leads to panics if pf is unloaded, as the unload
code does not unregister the pfil hooks (because the vnet is marked as
unhooked).
There's no need or reason to touch other vnets during initialisation.
Their pf_load_vnet() function will be triggered, which handles all
required initialisation.
Reviewed by: zec, gnn
Differential Revision: https://reviews.freebsd.org/D10592
vnet_pf_uninit() is called through vnet_deregister_sysuninit() and
linker_file_unload() when the pf module is unloaded. This is executed
after pf_unload() so we end up trying to take locks which have been
destroyed already.
Move pf_unload() to a separate SYSUNINIT() to ensure it's called after
all the vnet_pf_uninit() calls.
Differential Revision: https://reviews.freebsd.org/D10025
When forwarding pf tracks the size of the largest fragment in a fragmented
packet, and refragments based on this size.
It failed to ensure that this size was a multiple of 8 (as is required for all
but the last fragment), so it could end up generating incorrect fragments.
For example, if we received an 8 byte and 12 byte fragment pf would emit a first
fragment with 12 bytes of payload and the final fragment would claim to be at
offset 8 (not 12).
We now assert that the fragment size is a multiple of 8 in ip6_fragment(), so
other users won't make the same mistake.
Reported by: Antonios Atlasis <aatlasis at secfu net>
MFC after: 3 days
Prevent possible races in the pf_unload() / pf_purge_thread() shutdown
code. Lock the pf_purge_thread() with the new pf_end_lock to prevent
these races.
Use a shared/exclusive lock, as we need to also acquire another sx lock
(VNET_LIST_RLOCK). It's fine for both pf_purge_thread() and pf_unload()
to sleep,
Pointed out by: eri, glebius, jhb
Differential Revision: https://reviews.freebsd.org/D10026
In pf_route6() we re-run the ruleset with PF_FWD if the packet goes out
of a different interface. pf_test6() needs to know that the packet was
forwarded (in case it needs to refragment so it knows whether to call
ip6_output() or ip6_forward()).
This lead pf_test6() to try to evaluate rules against the PF_FWD
direction, which isn't supported, so it needs to treat PF_FWD as PF_OUT.
Once fwdir is set correctly the correct output/forward function will be
called.
PR: 217883
Submitted by: Kajetan Staszkiewicz
MFC after: 1 week
Sponsored by: InnoGames GmbH
Rules are unlinked in shutdown_pf(), so we must call
pf_unload_vnet_purge(), which frees unlinked rules, after that, not
before.
Reviewed by: eri, bz
Differential Revision: https://reviews.freebsd.org/D10040
When we unload we don't hold the pf_rules_lock, so we cannot call rw_sleep()
with it, because it would release a lock we do not hold. There's no need for the
lock either, so we can just tsleep().
While here also make the same change in pf_purge_thread(), because it explicitly
takes the lock before rw_sleep() and then immediately releases it afterwards.
If the call to pf_state_key_clone() in pf_get_translation() fails (i.e. there's
no more memory for it) it frees skp. This is wrong, because skp is a
pf_state_key **, so we need to free *skp, as is done later in the function.
Getting it wrong means we try to free a stack variable of the calling
pf_test_rule() function, and we panic.
inet_ntoa() cannot be used safely in a multithreaded environment
because it uses a static local buffer. Instead, use inet_ntoa_r()
with a buffer on the caller's stack.
This code had an INET6 conditional before this commit, but opt_inet6.h
was not included, so INET6 was never defined. Apparently, pf's OS
fingerprinting hasn't worked with IPv6 for quite some time.
This commit might fix it, but I didn't test that.
Reviewed by: gnn, kp
MFC after: 2 weeks
Relnotes: yes (if I/someone can test pf OS fingerprinting with IPv6)
Sponsored by: Dell EMC
Differential Revision: https://reviews.freebsd.org/D9625
initialized, this can cause a divide by zero (if the VNET initialization
takes to long to complete).
Obtained from: pfSense
MFC after: 2 weeks
Sponsored by: Rubicon Communications, LLC (Netgate)
Instead of taking an extra reference to deal with pfsync_q_ins()
and pfsync_q_del() taken and dropping a reference (resp,) make
it optional of those functions to take or drop a reference by
passing an extra argument.
Submitted by: glebius@
subrulenr is considered unset if it's set to -1, not if it's set to 1.
See contrib/tcpdump/print-pflog.c pflog_print() for a user.
This caused incorrect pflog output (tcpdump -n -e -ttt -i pflog0):
rule 0..16777216(match)
instead of the correct output of
rule 0/0(match)
PR: 214832
Submitted by: andywhite@gmail.com
Use after free happens for state that is deleted. The reference
count is what prevents the state from being freed. When the
state is dequeued, the reference count is dropped and the memory
freed. We can't dereference the next pointer or re-queue the
state.
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D8671
Ignore the ECN bits on 'tos' and 'set-tos' and allow to use
DCSP names instead of having to embed their TOS equivalents
as plain numbers.
Obtained from: OpenBSD
Sponsored by: OPNsense
Differential Revision: https://reviews.freebsd.org/D8165
The tag fastroute came from ipf and was removed in OpenBSD in 2011. The code
allows to skip the in pfil hooks and completely removes the out pfil invoke,
albeit looking up a route that the IP stack will likely find on its own.
The code between IPv4 and IPv6 is also inconsistent and marked as "XXX"
for years.
Submitted by: Franco Fichtner <franco@opnsense.org>
Differential Revision: https://reviews.freebsd.org/D8058
While here, prefer if_addrhead (FreeBSD) to if_addrlist (BSD compat) naming
for the interface address list in sctp_bsd_addr.c
Reviewed by: tuexen
Differential Revision: https://reviews.freebsd.org/D8051
Without this, rules using address ranges (e.g. "10.1.1.1 - 10.1.1.5") did not
match addresses correctly on little-endian systems.
PR: 211796
Obtained from: OpenBSD (sthen)
MFC after: 3 days
pf returns PF_PASS, PF_DROP, ... in the netpfil hooks, but the hook callers
expect to get E<foo> error codes.
Map the returns values. A pass is 0 (everything is OK), anything else means
pf ate the packet, so return EACCES, which tells the stack not to emit an ICMP
error message.
PR: 207598
teardown of VNETs once pf(4) has been shut down.
Properly split resources into VNET_SYS(UN)INITs and one time module
loading.
While here cover the INET parts in the uninit callpath with proper
#ifdefs.
Approved by: re (gjb)
Obtained from: projects/vnet
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
borrow pf's lock, and also make sure pflog goes after pf is gone
in order to avoid callouts in VNETs to an already freed instance.
Reported by: Ivan Klymenko, Johan Hendriks on current@ today
Obtained from: projects/vnet
Sponsored by: The FreeBSD Foundation
MFC after: 13 days
Approved by: re (gjb)
proper virtualisation, teardown, avoiding use-after-free, race conditions,
no longer creating a thread per VNET (which could easily be a couple of
thousand threads), gracefully ignoring global events (e.g., eventhandlers)
on teardown, clearing various globally cached pointers and checking
them before use.
Reviewed by: kp
Approved by: re (gjb)
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D6924
than removing the network interfaces first. This change is rather larger
and convoluted as the ordering requirements cannot be separated.
Move the pfil(9) framework to SI_SUB_PROTO_PFIL, move Firewalls and
related modules to their own SI_SUB_PROTO_FIREWALL.
Move initialization of "physical" interfaces to SI_SUB_DRIVERS,
move virtual (cloned) interfaces to SI_SUB_PSEUDO.
Move Multicast to SI_SUB_PROTO_MC.
Re-work parts of multicast initialisation and teardown, not taking the
huge amount of memory into account if used as a module yet.
For interface teardown we try to do as many of them as we can on
SI_SUB_INIT_IF, but for some this makes no sense, e.g., when tunnelling
over a higher layer protocol such as IP. In that case the interface
has to go along (or before) the higher layer protocol is shutdown.
Kernel hhooks need to go last on teardown as they may be used at various
higher layers and we cannot remove them before we cleaned up the higher
layers.
For interface teardown there are multiple paths:
(a) a cloned interface is destroyed (inside a VIMAGE or in the base system),
(b) any interface is moved from a virtual network stack to a different
network stack ("vmove"), or (c) a virtual network stack is being shut down.
All code paths go through if_detach_internal() where we, depending on the
vmove flag or the vnet state, make a decision on how much to shut down;
in case we are destroying a VNET the individual protocol layers will
cleanup their own parts thus we cannot do so again for each interface as
we end up with, e.g., double-frees, destroying locks twice or acquiring
already destroyed locks.
When calling into protocol cleanups we equally have to tell them
whether they need to detach upper layer protocols ("ulp") or not
(e.g., in6_ifdetach()).
Provide or enahnce helper functions to do proper cleanup at a protocol
rather than at an interface level.
Approved by: re (hrs)
Obtained from: projects/vnet
Reviewed by: gnn, jhb
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D6747
Adopt the OpenBSD syntax for setting and filtering on VLAN PCP values. This
introduces two new keywords: 'set prio' to set the PCP value, and 'prio' to
filter on it.
Reviewed by: allanjude, araujo
Approved by: re (gjb)
Obtained from: OpenBSD (mostly)
Differential Revision: https://reviews.freebsd.org/D6786
We were inconsistent about the use of time_second vs. time_uptime.
Always use time_uptime so the value can be meaningfully compared.
Submitted by: "Max" <maximos@als.nnov.ru>
MFC after: 4 days
When we guess the nature of the outbound packet (output vs. forwarding) we need
to take bridges into account. When bridging the input interface does not match
the output interface, but we're not forwarding. Similarly, it's possible for the
interface to actually be the bridge interface itself (and not a member interface).
PR: 202351
MFC after: 2 weeks
In the DIOCRSETADDRS ioctl() handler we allocate a table for struct pfr_addrs,
which is processed in pfr_set_addrs(). At the users request we also provide
feedback on the deleted addresses, by storing them after the new list
('bcopy(&ad, addr + size + i, sizeof(ad));' in pfr_set_addrs()).
This means we write outside the bounds of the buffer we've just allocated.
We need to look at pfrio_size2 instead (i.e. the size the user reserved for our
feedback). That'd allow a malicious user to specify a smaller pfrio_size2 than
pfrio_size though, in which case we'd still read outside of the allocated
buffer. Instead we allocate the largest of the two values.
Reported By: Paul J Murphy <paul@inetstat.net>
PR: 207463
MFC after: 5 days
Differential Revision: https://reviews.freebsd.org/D5426
There are number of radix consumers in kernel land (pf,ipfw,nfs,route)
with different requirements. In fact, first 3 don't have _any_ requirements
and first 2 does not use radix locking. On the other hand, routing
structure do have these requirements (rnh_gen, multipath, custom
to-be-added control plane functions, different locking).
Additionally, radix should not known anything about its consumers internals.
So, radix code now uses tiny 'struct radix_head' structure along with
internal 'struct radix_mask_head' instead of 'struct radix_node_head'.
Existing consumers still uses the same 'struct radix_node_head' with
slight modifications: they need to pass pointer to (embedded)
'struct radix_head' to all radix callbacks.
Routing code now uses new 'struct rib_head' with different locking macro:
RADIX_NODE_HEAD prefix was renamed to RIB_ (which stands for routing
information base).
New net/route_var.h header was added to hold routing subsystem internal
data. 'struct rib_head' was placed there. 'struct rtentry' will also
be moved there soon.
new return codes of -1 were mistakenly being considered "true". Callout_stop
now returns -1 to indicate the callout had either already completed or
was not running and 0 to indicate it could not be stopped. Also update
the manual page to make it more consistent no non-zero in the callout_stop
or callout_reset descriptions.
MFC after: 1 Month with associated callout change.
r289932 accidentally broke the rule skip calculation. The address family
argument to PF_ANEQ() is now important, and because it was set to 0 the macro
always evaluated to false.
This resulted in incorrect skip values, which in turn broke the rule
evaluations.
When using route-to (or reply-to) pf sends the packet directly to the output
interface. If that interface doesn't support checksum offloading the checksum
has to be calculated in software.
That was already done in the IPv4 case, but not for the IPv6 case. As a result
we'd emit packets with pseudo-header checksums (i.e. incorrect checksums).
This issue was exposed by the changes in r289316 when pf stopped performing full
checksum calculations for all packets.
Submitted by: Luoqi Chen
MFC after: 1 week
In certain configurations (mostly but not exclusively as a VM on Xen) pf
produced packets with an invalid TCP checksum.
The problem was that pf could only handle packets with a full checksum. The
FreeBSD IP stack produces TCP packets with a pseudo-header checksum (only
addresses, length and protocol).
Certain network interfaces expect to see the pseudo-header checksum, so they
end up producing packets with invalid checksums.
To fix this stop calculating the full checksum and teach pf to only update TCP
checksums if TSO is disabled or the change affects the pseudo-header checksum.
PR: 154428, 193579, 198868
Reviewed by: sbruno
MFC after: 1 week
Relnotes: yes
Sponsored by: RootBSD
Differential Revision: https://reviews.freebsd.org/D3779
Problem description:
How do we currently perform layer 2 resolution and header imposition:
For IPv4 we have the following chain:
ip_output() -> (ether|atm|whatever)_output() -> arpresolve()
Lookup is done in proper place (link-layer output routine) and it is possible
to provide cached lle data.
For IPv6 situation is more complex:
ip6_output() -> nd6_output() -> nd6_output_ifp() -> (whatever)_output() ->
nd6_storelladdr()
We have ip6_ouput() which calls nd6_output() instead of link output routine.
nd6_output() does the following:
* checks if lle exists, creates it if needed (similar to arpresolve())
* performes lle state transitions (similar to arpresolve())
* calls nd6_output_ifp() which pushes packets to link output routine along
with running SeND/MAC hooks regardless of lle state
(e.g. works as run-hooks placeholder).
After that, iface output routine like ether_output() calls nd6_storelladdr()
which performs lle lookup once again.
As a result, we perform lookup twice for each outgoing packet for most types
of interfaces. We also need to maintain runtime-checked table of 'nd6-free'
interfaces (see nd6_need_cache()).
Fix this behavior by eliminating first ND lookup. To be more specific:
* make all nd6_output() consumers use nd6_output_ifp() instead
* rename nd6_output[_slow]() to nd6_resolve_[slow]()
* convert nd6_resolve() and nd6_resolve_slow() to arpresolve() semantics,
e.g. copy L2 address to buffer instead of pushing packet towards lower
layers
* Make all nd6_storelladdr() users use nd6_resolve()
* eliminate nd6_storelladdr()
The resulting callchain is the following:
ip6_output() -> nd6_output_ifp() -> (whatever)_output() -> nd6_resolve()
Error handling:
Currently sending packet to non-existing la results in ip6_<output|forward>
-> nd6_output() -> nd6_output _lle() which returns 0.
In new scenario packet is propagated to <ether|whatever>_output() ->
nd6_resolve() which will return EWOULDBLOCK, and that result
will be converted to 0.
(And EWOULDBLOCK is actually used by IB/TOE code).
Sponsored by: Yandex LLC
Differential Revision: https://reviews.freebsd.org/D1469
If net.link.bridge.pfil_bridge is set we can end up thinking we're forwarding in
pf_test6() because the rcvif and the ifp (output interface) are different.
In that case we're bridging though, and the rcvif the the bridge member on which
the packet was received and ifp is the bridge itself.
If we'd set dir to PF_FWD we'd end up calling ip6_forward() which is incorrect.
Instead check if the rcvif is a member of the ifp bridge. (In other words, the
if_bridge is the ifp's softc). If that's the case we're not forwarding but
bridging.
PR: 202351
Reviewed by: eri
Differential Revision: https://reviews.freebsd.org/D3534
The crop/drop-ovl fragment scrub modes are not very useful and likely to confuse
users into making poor choices.
It's also a fairly large amount of complex code, so just remove the support
altogether.
Users who have 'scrub fragment crop|drop-ovl' in their pf configuration will be
implicitly converted to 'scrub fragment reassemble'.
Reviewed by: gnn, eri
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D3466
OpenBSD pf 4.5).
Fix argument ordering to memcpy as well as the size of the copy in the
(theoretical) case that pfi_buffer_cnt should be greater than ~_max.
This fix the failure when you hit the self table size and force it to be
resized.
MFC after: 3 days
Sponsored by: Rubicon Communications (Netgate)
CoDel is a parameterless queue discipline that handles variable bandwidth
and RTT.
It can be used as the single queue discipline on an interface or as a sub
discipline of existing queue disciplines such as PRIQ, CBQ, HFSC, FAIRQ.
Differential Revision: https://reviews.freebsd.org/D3272
Reviewd by: rpaulo, gnn (previous version)
Obtained from: pfSense
Sponsored by: Rubicon Communications (Netgate)
The size2 is the maximum userland buffer size (used when the addresses are
copied back to userland).
Obtained from: pfSense
MFC after: 3 days
Sponsored by: Rubicon Communications (Netgate)
When we allocate the struct pf_fragment in pf_fillup_fragment() we forgot to
initialise the fr_flags field. As a result we sometimes mistakenly thought the
fragment to not be a buffered fragment. This resulted in panics because we'd end
up freeing the pf_fragment but not removing it from V_pf_fragqueue (believing it
to be part of V_pf_cachequeue).
The next time we iterated V_pf_fragqueue we'd use a freed object and panic.
While here also fix a pf_fragment use after free in pf_normalize_ip().
pf_reassemble() frees the pf_fragment, so we can't use it any more.
PR: 201879, 201932
MFC after: 5 days
We don't use the direction of the fragments for anything. The frc_direction
field is assigned, but never read.
Just remove it.
Differential Revision: https://reviews.freebsd.org/D2773
Approved by: philip (mentor)
When we try to look up a pf_fragment with pf_find_fragment() we compare (see
pf_frag_compare()) addresses (and family), id but also protocol. We failed to
save the protocol to the pf_fragment in pf_fragcache(), resulting in failing
reassembly.
Differential Revision: https://reviews.freebsd.org/D2772
Fix a panic when handling fragmented ip4 packets with 'drop-ovl' set.
In that scenario we take a different branch in pf_normalize_ip(), taking us to
pf_fragcache() (rather than pf_reassemble()). In pf_fragcache() we create a
pf_fragment, but do not set the address family. This leads to a panic when we
try to insert that into pf_frag_tree because pf_addr_cmp(), which is used to
compare the pf_fragments doesn't know what to do if the address family is not
set.
Simply ensure that the address family is set correctly (always AF_INET in this
path).
PR: 200330
Differential Revision: https://reviews.freebsd.org/D2769
Approved by: philip (mentor), gnn (mentor)
years for head. However, it is continuously misused as the mpsafe argument
for callout_init(9). Deprecate the flag and clean up callout_init() calls
to make them more consistent.
Differential Revision: https://reviews.freebsd.org/D2613
Reviewed by: jhb
MFC after: 2 weeks
discontinued by its initial authors. In FreeBSD the code was already
slightly edited during the pf(4) SMP project. It is about to be edited
more in the projects/ifnet. Moving out of contrib also allows to remove
several hacks to the make glue.
Reviewed by: net@
If the direction is not PF_OUT we can never be forwarding. Some input packets
have rcvif != ifp (looped back packets), which lead us to ip6_forward() inbound
packets, causing panics.
Equally, we need to ensure that packets were really received and not locally
generated before trying to ip6_forward() them.
Differential Revision: https://reviews.freebsd.org/D2286
Approved by: gnn(mentor)
set past this point in the code. The packet should be dropped and
not massaged as it is here.
Differential Revision: https://reviews.freebsd.org/D2266
Submitted by: eri
Sponsored by: Rubicon Communications (Netgate)
In cases where we scrub (fragment reassemble) on both input and output
we risk ending up in infinite loops when forwarding packets.
Fragmented packets come in and get collected until we can defragment. At
that point the defragmented packet is handed back to the ip stack (at
the pfil point in ip6_input(). Normal processing continues.
Eventually we figure out that the packet has to be forwarded and we end
up at the pfil hook in ip6_forward(). After doing the inspection on the
defragmented packet we see that the packet has been defragmented and
because we're forwarding we have to refragment it.
In pf_refragment6() we split the packet up again and then ip6_forward()
the individual fragments. Those fragments hit the pfil hook on the way
out, so they're collected until we can reconstruct the full packet, at
which point we're right back where we left off and things continue until
we run out of stack.
Break that loop by marking the fragments generated by pf_refragment6()
as M_SKIP_FIREWALL. There's no point in processing those packets in the
firewall anyway. We've already filtered on the full packet.
Differential Revision: https://reviews.freebsd.org/D2197
Reviewed by: glebius, gnn
Approved by: gnn (mentor)
where we want to create a new IP datagram.
o Add support for RFC6864, which allows to set IP ID for atomic IP
datagrams to any value, to improve performance. The behaviour is
controlled by net.inet.ip.rfc6864 sysctl knob, which is enabled by
default.
o In case if we generate IP ID, use counter(9) to improve performance.
o Gather all code related to IP ID into ip_id.c.
Differential Revision: https://reviews.freebsd.org/D2177
Reviewed by: adrian, cy, rpaulo
Tested by: Emeric POUPON <emeric.poupon stormshield.eu>
Sponsored by: Netflix
Sponsored by: Nginx, Inc.
Relnotes: yes
On Ethernet packets have a minimal length, so very short packets get padding
appended to them. This padding is not stripped off in ip6_input() (due to
support for IPv6 Jumbograms, RFC2675).
That means PF needs to be careful when reassembling fragmented packets to not
include the padding in the reassembled packet.
While here also remove the 'Magic from ip_input.' bits. Splitting up and
re-joining an mbuf chain here doesn't make any sense.
Differential Revision: https://reviews.freebsd.org/D2189
Approved by: gnn (mentor)
When forwarding fragmented IPv6 packets and filtering with PF we
reassemble and refragment. That means we generate new fragment headers
and a new fragment ID.
We already save the fragment IDs so we can do the reassembly so it's
straightforward to apply the incoming fragment ID on the refragmented
packets.
Differential Revision: https://reviews.freebsd.org/D2188
Approved by: gnn (mentor)
size as they arrived in. This allows the sender to determine the optimal
fragment size by Path MTU Discovery.
Roughly based on the OpenBSD work by Alexander Bluhm.
Submitted by: Kristof Provost
Differential Revision: D1767
That partially fixes IPv6 fragment handling. Thanks to Kristof for
working on that.
Submitted by: Kristof Provost
Tested by: peter
Differential Revision: D1765
very questionable, since it makes vimages more dependent on each other. But
the reason for the backout is that it screwed up shutting down the pf purge
threads, and now kernel immedially panics on pf module unload. Although module
unloading isn't an advertised feature of pf, it is very important for
development process.
I'd like to not backout r276746, since in general it is good. But since it
has introduced numerous build breakages, that later were addressed in
r276841, r276756, r276747, I need to back it out as well. Better replay it
in clean fashion from scratch.
Split functions that initialize various pf parts into their
vimage parts and global parts.
Since global parts appeared to be only mutex initializations, just
abandon them and use MTX_SYSINIT() instead.
Kill my incorrect VNET_FOREACH() iterator and instead use correct
approach with VNET_SYSINIT().
PR: 194515
Differential Revision: D1309
Submitted by: glebius, Nikos Vassiliadis <nvass@gmx.com>
Reviewed by: trociny, zec, gnn
- Wrong integer type was specified.
- Wrong or missing "access" specifier. The "access" specifier
sometimes included the SYSCTL type, which it should not, except for
procedural SYSCTL nodes.
- Logical OR where binary OR was expected.
- Properly assert the "access" argument passed to all SYSCTL macros,
using the CTASSERT macro. This applies to both static- and dynamically
created SYSCTLs.
- Properly assert the the data type for both static and dynamic
SYSCTLs. In the case of static SYSCTLs we only assert that the data
pointed to by the SYSCTL data pointer has the correct size, hence
there is no easy way to assert types in the C language outside a
C-function.
- Rewrote some code which doesn't pass a constant "access" specifier
when creating dynamic SYSCTL nodes, which is now a requirement.
- Updated "EXAMPLES" section in SYSCTL manual page.
MFC after: 3 days
Sponsored by: Mellanox Technologies
struct ifnet if_oqdrops.
Some netgraph modules used ifqueue w/o ifnet. Accounting of queue drops
is simply removed from them. There were no API to read this statistic.
Sponsored by: Netflix
Sponsored by: Nginx, Inc.
otherwise bad consequences including a routing loop can occur.
Move pf_set_rt_ifp() earlier in state creation sequence and
inline it, cutting some extra code.
PR: 183997
Submitted by: Kajetan Staszkiewicz <vegeta tuxpowered.net>
Sponsored by: InnoGames GmbH
- Do not count global number of states and of src_nodes,
use uma_zone_get_cur() to obtain values.
- Struct pf_status becomes merely an ioctl API structure,
and moves to netpfil/pf/pf.h with its constants.
- V_pf_status is now of type struct pf_kstatus.
Submitted by: Kajetan Staszkiewicz <vegeta tuxpowered.net>
Sponsored by: InnoGames GmbH
These changes prevent sysctl(8) from returning proper output,
such as:
1) no output from sysctl(8)
2) erroneously returning ENOMEM with tools like truss(1)
or uname(1)
truss: can not get etype: Cannot allocate memory
there is an environment variable which shall initialize the SYSCTL
during early boot. This works for all SYSCTL types both statically and
dynamically created ones, except for the SYSCTL NODE type and SYSCTLs
which belong to VNETs. A new flag, CTLFLAG_NOFETCH, has been added to
be used in the case a tunable sysctl has a custom initialisation
function allowing the sysctl to still be marked as a tunable. The
kernel SYSCTL API is mostly the same, with a few exceptions for some
special operations like iterating childrens of a static/extern SYSCTL
node. This operation should probably be made into a factored out
common macro, hence some device drivers use this. The reason for
changing the SYSCTL API was the need for a SYSCTL parent OID pointer
and not only the SYSCTL parent OID list pointer in order to quickly
generate the sysctl path. The motivation behind this patch is to avoid
parameter loading cludges inside the OFED driver subsystem. Instead of
adding special code to the OFED driver subsystem to post-load tunables
into dynamically created sysctls, we generalize this in the kernel.
Other changes:
- Corrected a possibly incorrect sysctl name from "hw.cbb.intr_mask"
to "hw.pcic.intr_mask".
- Removed redundant TUNABLE statements throughout the kernel.
- Some minor code rewrites in connection to removing not needed
TUNABLE statements.
- Added a missing SYSCTL_DECL().
- Wrapped two very long lines.
- Avoid malloc()/free() inside sysctl string handling, in case it is
called to initialize a sysctl from a tunable, hence malloc()/free() is
not ready when sysctls from the sysctl dataset are registered.
- Bumped FreeBSD version to indicate SYSCTL API change.
MFC after: 2 weeks
Sponsored by: Mellanox Technologies
!(PFRULE_FRAGCROP|PFRULE_FRAGDROP) case.
o In the (PFRULE_FRAGCROP|PFRULE_FRAGDROP) case we should allocate mtag
if we don't find any.
Tested by: Ian FREISLICH <ianf cloudseed.co.za>
- DIOCADDADDR adds addresses and puts them into V_pf_pabuf
- DIOCADDRULE takes all addresses from V_pf_pabuf and links
them into rule.
The ugly part is that if address is a table, then it is initialized
in DIOCADDRULE, because we need ruleset, and DIOCADDADDR doesn't
supply ruleset. But if address is a dynaddr, we need address family,
and address family could be different for different addresses in one
rule, so dynaddr is initialized in DIOCADDADDR.
This leads to the entangled state of addresses on V_pf_pabuf. Some are
initialized, and some not. That's why running pf_empty_pool(&V_pf_pabuf)
can lead to a panic on a NULL table address.
Since proper fix requires API/ABI change, for now simply plug the panic
in pf_empty_pool().
Reported by: danger
De-virtualize UMA zone pf_mtag_z and move to global initialization part.
The m_tag struct does not know about vnet context and the pf_mtag_free()
callback is called unaware of current vnet. This causes a panic.
MFC after: 1 week
The m_tag struct does not know about vnet context and the pf_mtag_free()
callback is called unaware of current vnet. This causes a panic.
Reviewed by: Nikos Vassiliadis, trociny@
- Use counter(9) for rt_pksent (former rt_rmx.rmx_pksent). This
removes another cache trashing ++ from packet forwarding path.
- Create zini/fini methods for the rtentry UMA zone. Via initialize
mutex and counter in them.
- Fix reporting of rmx_pksent to routing socket.
- Fix netstat(1) to report "Use" both in kvm(3) and sysctl(3) mode.
The change is mostly targeted for stable/10 merge. For head,
rt_pksent is expected to just disappear.
Discussed with: melifaro
Sponsored by: Netflix
Sponsored by: Nginx, Inc.
race prone. Some just gather statistics, but some are later used in
different calculations.
A real problem was the race provoked underflow of the states_cur counter
on a rule. Once it goes below zero, it wraps to UINT32_MAX. Later this
value is used in pf_state_expires() and any state created by this rule
is immediately expired.
Thus, make fields states_cur, states_tot and src_nodes of struct
pf_rule be counter(9)s.
Thanks to Dennis for providing me shell access to problematic box and
his help with reproducing, debugging and investigating the problem.
Thanks to: Dennis Yusupoff <dyr smartspb.net>
Also reported by: dumbbell, pgj, Rambler
Sponsored by: Nginx, Inc.
where "m" is number of source nodes and "n" is number of states. Thus,
on heavy loaded router its processing consumed a lot of CPU time.
Reimplement it with O(m+n) complexity. We first scan through source
nodes and disconnect matching ones, putting them on the freelist and
marking with a cookie value in their expire field. Then we scan through
the states, detecting references to source nodes with a cookie, and
disconnect them as well. Then the freelist is passed to pf_free_src_nodes().
In collaboration with: Kajetan Staszkiewicz <kajetan.staszkiewicz innogames.de>
PR: kern/176763
Sponsored by: InnoGames GmbH
Sponsored by: Nginx, Inc.
- Removed pf_remove_src_node().
- Introduce pf_unlink_src_node() and pf_unlink_src_node_locked().
These function do not proceed with freeing of a node, just disconnect
it from storage.
- New function pf_free_src_nodes() works on a list of previously
disconnected nodes and frees them.
- Utilize new API in pf_purge_expired_src_nodes().
In collaboration with: Kajetan Staszkiewicz <kajetan.staszkiewicz innogames.de>
Sponsored by: InnoGames GmbH
Sponsored by: Nginx, Inc.
parts and global parts.
- Since global parts appeared to be only mutex initializations, just
abandon them and use MTX_SYSINIT() instead.
- Kill my incorrect VNET_FOREACH() iterator and instead use correct
approach with VNET_SYSINIT().
Submitted by: Nikos Vassiliadis <nvass gmx.com>
Reviewed by: trociny
- Do not return blindly if proto isn't ICMP.
- The dport is in network order, so fix comparisons.
- Remove ridiculous htonl(arc4random()).
- Push local variable to a narrower block.
Original log:
Make sure pd2 has a pointer to the icmp header in the payload; fixes
panic seen with some some icmp types in icmp error message payloads.
Obtained from: OpenBSD
Stricter state checking for ICMP and ICMPv6 packets: include the ICMP type
in one port of the state key, using the type to determine which
side should be the id, and which should be the type. Also:
- Handle ICMP6 messages which are typically sent to multicast
addresses but recieve unicast replies, by doing fallthrough lookups
against the correct multicast address. - Clear up some mistaken
assumptions in the PF code:
- Not all ICMP packets have an icmp_id, so simulate
one based on other data if we can, otherwise set it to 0.
- Don't modify the icmp id field in NAT unless it's echo
- Use the full range of possible id's when NATing icmp6 echoy
Difference with OpenBSD version:
- C99ify the new code
- WITHOUT_INET6 safe
Reviewed by: glebius
Obtained from: OpenBSD
in net, to avoid compatibility breakage for no sake.
The future plan is to split most of non-kernel parts of
pfvar.h into pf.h, and then make pfvar.h a kernel only
include breaking compatibility.
Discussed with: bz
to this event, adding if_var.h to files that do need it. Also, include
all includes that now are included due to implicit pollution via if_var.h
Sponsored by: Netflix
Sponsored by: Nginx, Inc.
date: 2010/02/04 14:10:12; author: sthen; state: Exp; lines: +24 -19;
pf_get_sport() picks a random port from the port range specified in a
nat rule. It should check to see if it's in-use (i.e. matches an existing
PF state), if it is, it cycles sequentially through other ports until
it finds a free one. However the check was being done with the state
keys the wrong way round so it was never actually finding the state
to be in-use.
- switch the keys to correct this, avoiding random state collisions
with nat. Fixes PR 6300 and problems reported by robert@ and viq.
- check pf_get_sport() return code in pf_test(); if port allocation
fails the packet should be dropped rather than sent out untranslated.
Help/ok claudio@.
Some additional changes to 1.12:
- We also need to bzero() the key to zero padding, otherwise key
won't match.
- Collapse two if blocks into one with ||, since both conditions
lead to the same processing.
- Only naddr changes in the cycle, so move initialization of other
fields above the cycle.
- s/u_intXX_t/uintXX_t/g
PR: kern/181690
Submitted by: Olivier Cochard-Labbé <olivier cochard.me>
Sponsored by: Nginx, Inc.
Before this change state creating sequence was:
1) lock wire key hash
2) link state's wire key
3) unlock wire key hash
4) lock stack key hash
5) link state's stack key
6) unlock stack key hash
7) lock ID hash
8) link into ID hash
9) unlock ID hash
What could happen here is that other thread finds the state via key
hash lookup after 6), locks ID hash and does some processing of the
state. When the thread creating state unblocks, it finds the state
it was inserting already non-virgin.
Now we perform proper interlocking between key hash locks and ID hash
lock:
1) lock wire & stack hashes
2) link state's keys
3) lock ID hash
4) unlock wire & stack hashes
5) link into ID hash
6) unlock ID hash
To achieve that, the following hacking was performed in pf_state_key_attach():
- Key hash mutex is marked with MTX_DUPOK.
- To avoid deadlock on 2 key hash mutexes, we lock them in order determined
by their address value.
- pf_state_key_attach() had a magic to reuse a > FIN_WAIT_2 state. It unlinked
the conflicting state synchronously. In theory this could require locking
a third key hash, which we can't do now.
Now we do not remove the state immediately, instead we leave this task to
the purge thread. To avoid conflicts in a short period before state is
purged, we push to the very end of the TAILQ.
- On success, before dropping key hash locks, pf_state_key_attach() locks
ID hash and returns.
Tested by: Ian FREISLICH <ianf clue.co.za>
and that can drive someone crazy. While m_get2() is young and not
documented yet, change its order of arguments to match m_getm2().
Sorry for churn, but better now than later.
length packets, which was actually harmless.
Note that peers with different version of head/ may grow this
counter, but it is harmless - all pfsync data is processed.
Reported & tested by: Anton Yuzhaninov <citrin citrin.ru>
Sponsored by: Nginx, Inc
- Add my copyright to files I've touched a lot this year.
- Add dash in front of all copyright notices according to style(9).
- Move $OpenBSD$ down below copyright notices.
- Remove extra line between cdefs.h and __FBSDID.
set.
As the checks don't require vnet context, this is fixed by setting
vnet after the checks.
PR: kern/160541
Submitted by: Nikos Vassiliadis (slightly different approach)
date: 2009/03/31 01:21:29; author: dlg; state: Exp; lines: +9 -16
...
this also firms up some of the input parsing so it handles short frames a
bit better.
This actually fixes reading beyond mbuf data area in pfsync_input(), that
may happen at certain pfsync datagrams.
as r242694):
do better detection of when we have a better version of the tcp sequence
windows than our peer.
this resolves the last of the pfsync traffic storm issues ive been able to
produce, and therefore makes it possible to do usable active-active
statuful firewalls with pf.
id hash. If a state has been disconnected from id hash, its rule pointers
can no longer be dereferenced, and referenced memory can't be modified.
Thus, move rule statistics from pf_free_rule() to pf_unlink_rule() and
update them prior to releasing id hash slot lock.
Reported by: Ian FREISLICH <ianf cloudseed.co.za>
from pfsync:
- Call into pfsync_delete_state() holding the state lock.
- Set the state timeout to PFTM_UNLINKED after state has been moved
to the PFSYNC_S_DEL queue in pfsync.
Reported by: Ian FREISLICH <ianf cloudseed.co.za>
date: 2009/06/12 02:03:51; author: dlg; state: Exp; lines: +59 -69
rewrite the way states from pfsync are merged into the local state tree
and the conditions on which pfsync will notify its peers on a stale update.
each side (ie, the sending and receiving side) of the state update is
compared separately. any side that is further along than the local state
tree is merged. if any side is further along in the local state table, an
update is sent out telling the peers about it.
case keys had already been freed. If encountering such state, then
just release last reference.
Not sure this can happen as a runtime race, but can be reproduced by
the following scenario:
- enable pfsync
- disable pfsync
- wait some time
- enable pfsync
on checksums directly from mbuf flags. This simplifies code.
o Clear CSUM_IP from the mbuf in ip_fragment() if we did checksums in
hardware. Some driver may not announce CSUM_IP in theur if_hwassist,
although try to do checksums if CSUM_IP set on mbuf. Example is em(4).
o While here, consistently use CSUM_IP instead of its alias CSUM_DELAY_IP.
After this change CSUM_DELAY_IP vanishes from the stack.
Submitted by: Sebastian Kuzminsky <seb lineratesystems.com>
in network byte order. Any host byte order processing is
done in local variables and host byte order values are
never[1] written to a packet.
After this change a packet processed by the stack isn't
modified at all[2] except for TTL.
After this change a network stack hacker doesn't need to
scratch his head trying to figure out what is the byte order
at the given place in the stack.
[1] One exception still remains. The raw sockets convert host
byte order before pass a packet to an application. Probably
this would remain for ages for compatibility.
[2] The ip_input() still subtructs header len from ip->ip_len,
but this is planned to be fixed soon.
Reviewed by: luigi, Maxim Dounin <mdounin mdounin.ru>
Tested by: ray, Olivier Cochard-Labbe <olivier cochard.me>
now use function calls:
if_clone_simple()
if_clone_advanced()
to initialize a cloner, instead of macros that initialize if_clone
structure.
Discussed with: brooks, bz, 1 year ago
host byte order, was sometimes called with net byte order. Since we are
moving towards net byte order throughout the stack, the function was
converted to expect net byte order, and its consumers fixed appropriately:
- ip_output(), ipfilter(4) not changed, since already call
in_delayed_cksum() with header in net byte order.
- divert(4), ng_nat(4), ipfw_nat(4) now don't need to swap byte order
there and back.
- mrouting code and IPv6 ipsec now need to switch byte order there and
back, but I hope, this is temporary solution.
- In ipsec(4) shifted switch to net byte order prior to in_delayed_cksum().
- pf_route() catches up on r241245 changes to ip_output().
- All packets in NETISR_IP queue are in net byte order.
- ip_input() is entered in net byte order and converts packet
to host byte order right _after_ processing pfil(9) hooks.
- ip_output() is entered in host byte order and converts packet
to net byte order right _before_ processing pfil(9) hooks.
- ip_fragment() accepts and emits packet in net byte order.
- ip_forward(), ip_mloopback() use host byte order (untouched actually).
- ip_fastforward() no longer modifies packet at all (except ip_ttl).
- Swapping of byte order there and back removed from the following modules:
pf(4), ipfw(4), enc(4), if_bridge(4).
- Swapping of byte order added to ipfilter(4), based on __FreeBSD_version
- __FreeBSD_version bumped.
- pfil(9) manual page updated.
Reviewed by: ray, luigi, eri, melifaro
Tested by: glebius (LE), ray (BE)
- Write method of a queue now is void,length of item is taken
as queue property.
- Write methods don't need to know about mbud, supply just buf
to them.
- No need for safe queue iterator in pfsync_sendout().
Obtained from: OpenBSD
pf_purge_expired_states().
Now pf purging daemon stores the current hash table index on stack
in pf_purge_thread(), and supplies it to next iteration of
pf_purge_expired_states(). The latter returns new index back.
The important change is that whenever pf_purge_expired_states() wraps
around the array it returns immediately. This makes our knowledge about
status of states expiry run more consistent. Prior to this change it
could happen that n-th run stopped on i-th entry, and returned (1) as
full run complete, then next (n+1) full run stopped on j-th entry, where
j < i, and that broke the mark-and-sweep algorythm that saves references
rules. A referenced rule was freed, and this later lead to a crash.
we are actually editing table, which means editing rules,
thus we need writer access to 'em.
Fix this by offloading the update of table to the same taskqueue,
we already use for flushing. Since taskqueues major task is now
overloading, and flushing is optional, do mechanical rename
s/flush/overload/ in the code related to the taskqueue.
Since overloading tasks do unsafe referencing of rules, provide
a bandaid in pf_purge_unlinked_rules(). If the latter sees any
queued tasks, then it skips purging for this run.
In table code:
- Assert any lock in pfr_lookup_addr().
- Assert writer lock in pfr_route_kentry().
This is important to secure a small timeframe at boot time, when
network is already configured, but pf(4) is not yet.
PR: kern/171622
Submitted by: Olivier Cochard-LabbИ <olivier cochard.me>
1) Ruleset parser uses a global variable for anchor stack.
2) When processing a wildcard anchor, matching anchors are marked.
To fix the first one:
o Allocate anchor processing stack on stack. To make this allocation
as small as possible, following measures taken:
- Maximum stack size reduced from 64 to 32.
- The struct pf_anchor_stackframe trimmed by one pointer - parent.
We can always obtain the parent via the rule pointer.
- When pf_test_rule() calls pf_get_translation(), the former lends
its stack to the latter, to avoid recursive allocation 32 entries.
The second one appeared more tricky. The code, that marks anchors was
added in OpenBSD rev. 1.516 of pf.c. According to commit log, the idea
is to enable the "quick" keyword on an anchor rule. The feature isn't
documented anywhere. The most obscure part of the 1.516 was that code
examines the "match" mark on a just processed child, which couldn't be
put here by current frame. Since this wasn't documented even in the
commit message and functionality of this is not clear to me, I decided
to drop this examination for now. The rest of 1.516 is redone in a
thread safe manner - the mark isn't put on the anchor itself, but on
current stack frame. To avoid growing stack frame, we utilize LSB
from the rule pointer, relying on kernel malloc(9) returning pointer
aligned addresses.
Discussed with: dhartmei
reside, and move there ipfw(4) and pf(4).
o Move most modified parts of pf out of contrib.
Actual movements:
sys/contrib/pf/net/*.c -> sys/netpfil/pf/
sys/contrib/pf/net/*.h -> sys/net/
contrib/pf/pfctl/*.c -> sbin/pfctl
contrib/pf/pfctl/*.h -> sbin/pfctl
contrib/pf/pfctl/pfctl.8 -> sbin/pfctl
contrib/pf/pfctl/*.4 -> share/man/man4
contrib/pf/pfctl/*.5 -> share/man/man5
sys/netinet/ipfw -> sys/netpfil/ipfw
The arguable movement is pf/net/*.h -> sys/net. There are
future plans to refactor pf includes, so I decided not to
break things twice.
Not modified bits of pf left in contrib: authpf, ftp-proxy,
tftp-proxy, pflogd.
The ipfw(4) movement is planned to be merged to stable/9,
to make head and stable match.
Discussed with: bz, luigi
