Packets only ever reference the flow while holding its lock. This
means than any code possibly evicting the flow will have to wait
for the existing users to complete their work. Therefore the use_cnt
serves no function anymore and can be removed.
Issue: 5718
This commit switches the majority of time handling to a new type --
SCTime_t -- which is a 64 bit container for time:
- 44 bits -- seconds
- 20 bits -- useconds
Adds a framework for setting exception policies. These would be called
when the engine reaches some kind of exception condition, like hitting
a memcap or some traffic processing error.
The policy gives control over what should happen next: drop the packet,
drop the packet and flow, bypass, etc.
Implements the policy for:
stream: If stream session or reassembly memcaps are hit call the
memcap policy on the packet and flow.
flow: Apply policy when memcap is reached and no flow could be
freed up.
defrag: Apply policy when no tracker could be picked up.
app-layer: Apply ppolicy if a parser reaches an error state.
All options default to 'ignore', which means the default behavior
is unchanged.
Adds commandline options: add simulation options for exceptions. These
are only exposed if compiled with `--enable-debug`.
Ticket: #5214.
Ticket: #5215.
Ticket: #5216.
Ticket: #5218.
Ticket: #5194.
Completes commit e2370d6861
for all the fuzz targets processing pcaps
using a generic function.
FlowShutdown is not used because it uses the loop to destroy
mutexes, which we want to reuse for fuzzing
Currently the ICMP emergency-bypassed value defined in suricata.conf is
overwriting the UDP value rather than correctly setting it for ICMP.
This commit corrects this bug so that the ICMP value can be set as
expected.
Goals:
- reduce locking
- take advantage of 'hot' caches
- better locality
Locking reduction
New flow spare pool. The global pool is implmented as a list of blocks,
where each block has a 100 spare flows. Worker threads fetch a block at
a time, storing the block in the local thread storage.
Flow Recycler now returns flows to the pool is blocks as well.
Flow Recycler fetches all flows to be processed in one step instead of
one at a time.
Cache 'hot'ness
Worker threads now check the timeout of flows they evaluate during lookup.
The worker will have to read the flow into cache anyway, so the added
overhead of checking the timeout value is minimal. When a flow is considered
timed out, one of 2 things happens:
- if the flow is 'owned' by the thread it is handled locally. Handling means
checking if the flow needs 'timeout' work.
- otherwise, the flow is added to a special 'evicted' list in the flow
bucket where it will be picked up by the flow manager.
Flow Manager timing
By default the flow manager now tries to do passes of the flow hash in
smaller steps, where the goal is to do full pass in 8 x the lowest timeout
value it has to enforce. So if the lowest timeout value is 30s, a full pass
will take 4 minutes. The goal here is to reduce locking overhead and not
get in the way of the workers.
In emergency mode each pass is full, and lower timeouts are used.
Timing of the flow manager is also no longer relying on pthread condition
variables, as these generally cause waking up much quicker than the desired
timout. Instead a simple (u)sleep loop is used.
Both changes reduce the number of hash passes a lot.
Emergency behavior
In emergency mode there a number of changes to the workers. In this scenario
the flow memcap is fully used up and it is unavoidable that some flows won't
be tracked.
1. flow spare pool fetches are reduced to once a second. This avoids locking
overhead, while the chance of success was very low.
2. getting an active flow directly from the hash skips flows that had very
recent activity to avoid the scenario where all flows get only into the
NEW state before getting reused. Rather allow some to have a chance of
completing.
3. TCP packets that are not SYN packets will not get a used flow, unless
stream.midstream is enabled. The goal here is again to avoid evicting
active flows unnecessarily.
Better Localily
Flow Manager injects flows into the worker threads now, instead of one or
two packets. Advantage of this is that the worker threads can get packets
from their local packet pools, avoiding constant overhead of packets returning
to 'foreign' pools.
Counters
A lot of flow counters have been added and some have been renamed.
Overall the worker threads increment 'flow.wrk.*' counters, while the flow
manager increments 'flow.mgr.*'.
Additionally, none of the counters are snapshots anymore, they all increment
over time. The flow.memuse and flow.spare counters are exceptions.
Misc
FlowQueue has been split into a FlowQueuePrivate (unlocked) and FlowQueue.
Flow no longer has 'prev' pointers and used a unified 'next' pointer for
both hash and queue use.
This commit adds MAC address output to the EVE-JSON format. We follow the
remarks made in Redmine ticket #962: for packets, log MAC src/dst as a
scalar field in EVE; for flows, log MAC src/dst as lists in EVE. Field names
are different between flow and packet context to avoid type confusion
(src_mac vs. src_macs). Configuration approach and JSON representation is
taken from previous GitHub PR #2700.
Replaces all patterns of SCLogError() followed by exit() with
FatalError(). Cocci script to do this:
@@
constant C;
constant char[] msg;
@@
- SCLogError(C,
+ FatalError(SC_ERR_FATAL,
msg);
- exit(EXIT_FAILURE);
Closes redmine ticket 3188.
Make sure to cleanup expectations for a flow as the first step, before
parts of the flow itself are getting cleaned/freed.
Also indicate use unlikely as flows with expectations should be relatively
rare.
When a flow timeout, we can have still existing expectations that
are linked to this flow. Given that there is a delay between the
real ending of the flow and its destruction by Suricata, the
expectation should be already honored so we can assume the risk
to clean the expectations that have been triggered by the
to-be-deleted flow.
This define is used to remove reference to capture bypass in case
no capture method implementing this is active.
This patch also introduces CAPTURE_OFFLOAD_MANAGER that is defined
if we need the flow bypass manager code.
Kernel time is not available (and/or costly) on NIC such as
Netronome so we update the logic to detect dead flows based on a
lack of update of packets counters. This way, the XDP filter will
be usable by network card.
This patch also updates the ebpf code to support per CPU and
regular mapping. Netronome is not supporting it and the structure
is using atomic for counter so the cost of simultaneous update
is really low.
This patch also updates the xdp_filter to be able to select if the
flow table is per CPU on shared. Second option will be used for
hardward offload. To deactivate the per cpu hash, you need to set
USE_PERCPU_HASH to 0.
This patch also adds an new option to af-packet named no-percpu-hash
If this option is set to yes then the Flow bypassed manager thread
will use one CPU instead of the number of cores. By doing that
we are able to handle the case where USE_PERCPU_HASH is unset (so
hardware offload for Netronome).
This patch also remove aligment indications in the eBPF filter. This
was not really needed and it seems it is causing problem with
some recent version of LLVM toolchain.
If a stream is async we see only on side of the traffic. This would
lead to the flow engine not flagging packets as 'established' even
if the flow state was in fact established. The flow was tagged as
such by the TCP engine.
This patch considers the flow state for setting the packet flag.
Bug #2491.
Main objective of the function is to be able to bypass a flow on
other interfaces. This is necessary in AF_PACKET case as the flow
table are per interface.
This adds new functions that will be called
through unix-socket and permit to update
and show memcap value.
The memcap value needs to be handled in a
thread safe way, so for this reason it is
declared as atomic var.
FlowGetMemuse() function is made as public
because the memuse value will be shown
through unix-socket.
This commit fixes multiple NULL-pointer dereferences in FlowInitConfig after reading in config-values(flow.hash-size, flow.prealloc and flow.memcap) for flow. Here is a sample ASAN-output:
=================================================================
ERROR: AddressSanitizer: SEGV on unknown address 0x000000000000 (pc 0x7fea73456646 bp 0x7fffd70e1ba0 sp 0x7fffd70e1328 T0)
0 0x7fea73456645 in strlen (/lib/x86_64-linux-gnu/libc.so.6+0x80645)
1 0x7fea76c98eec (/usr/lib/x86_64-linux-gnu/libasan.so.3+0x3beec)
2 0x5643efb4c205 in FlowInitConfig /root/suricata-1/src/flow.c:455
3 0x5643efcd1751 in PreRunInit /root/suricata-1/src/suricata.c:2247
4 0x5643efcd49f4 in PostConfLoadedSetup /root/suricata-1/src/suricata.c:2748
5 0x5643efcd5402 in main /root/suricata-1/src/suricata.c:2884
6 0x7fea733f62b0 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x202b0)
7 0x5643ef8761a9 in _start (/usr/local/bin/suricata+0xc51a9)
Ticketno: Bug #2349
Netflow entry collects the minimum and maximum
time to live during the life of the incoming flow.
This adds those field to a netflow event.
Signed-off-by: Eric Leblond <eric@regit.org>
Support changing the application level protocol for a flow. This is
needed by STARTTLS and HTTP CONNECT to switch from the original
alproto to tls.
This commit allows a flag to be set 'FLOW_CHANGE_PROTO', which
triggers a new protocol detection on the next packet for a flow.
Set flags by default:
-Wmissing-prototypes
-Wmissing-declarations
-Wstrict-prototypes
-Wwrite-strings
-Wcast-align
-Wbad-function-cast
-Wformat-security
-Wno-format-nonliteral
-Wmissing-format-attribute
-funsigned-char
Fix minor compiler warnings for these new flags on gcc and clang.