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
AF_XDP support is a recent technology introduced that aims at improving
capture performance. With this update, Suricata now provides a new
capture source 'af-xdp' that attaches an eBPF program to the network
interface card. Packets received in the NIC queue are forwarded to
a RX ring in user-space, bypassing the Linux network stack.
Note, there is a configuration option (force-xdp-mode) that forces the
packet through the normal Linux network stack.
libxdp and libbpf is required for this feature and is compile time
configured.
This capture source operates on single and multi-queue NIC's via
suricata.yaml. Here, various features can be enabled, disabled
or edited as required by the use case.
This feature currently only supports receiving packets via AF_XDP,
no TX support has been developed.
Ticket: https://redmine.openinfosecfoundation.org/issues/3306
Additional reading:
https://www.kernel.org/doc/html/latest/networking/af_xdp.html
Lock is only held to update/check ints, so spin lock will be more
efficient.
Place the member of Packet in a new "persistent" area to make it
clear this is not touched by the PacketReinit logic.
Ticket: #5592.
Update DROP action handling in tunnel packets. DROP/REJECT action is set
to outer (root) and inner packet.
Check action flags both against outer (root) and inner packet.
Remove PACKET_SET_ACTION macro. Replace with RESET for the one reset usecase.
The reason to remove is to make the logic easier to understand.
Reduce scope of RESET macros.
Rename PacketTestAction to PacketCheckAction except in unittests. Keep
PacketTestAction as a wrapper around PacketCheckAction. This makes it
easier to trace the action handling in the real code.
Fix rate_filter setting actions directly.
General code cleanups.
Bug: #5571.
Track packets that updated the app-layer, and for those run
the transaction housekeeping and output-tx logging loops.
Do the same of end of flow packets.
This skips needless iterations over the transaction stores.
Work towards making `suricata-common.h` only introduce system headers
and other things that are independent of complex internal Suricata
data structures.
Update files to compile after this.
Remove special DPDK handling for strlcpy and strlcat, as this caused
many compilation failures w/o including DPDK headers for all files.
Remove packet macros from decode.h and move them into their own file,
turn them into functions and rename them to match our function naming
policy.
This allows to set a midstream-policy that can:
- fail closed (stream.midstream-policy=drop-flow)
- fail open (stream.midstream-policy=pass-flow)
- bypass stream (stream.midstream-policy=bypass)
- do nothing (default behavior)
Usage and behavior:
If stream.midstream-policy is set then if Suricata identifies a midstream flow
it will apply the corresponding action associated with the policy.
No setting means Suricata will not apply such policies, either inspecting the
flow (if stream.midstream=true) or ignoring it stream.midstream=false.
Task #5468
A Packet may be dropped due to several different reasons. This change
adds action as a parameter, so we can update the packet action when we
drop it, instead of setting it to drop.
Related to
Bug #5458
The maximum of possible alerts triggered by a unique packet was
hardcoded to 15. With usage of 'noalert' rules, that limit could be
reached somewhat easily. Make that configurable via suricata.yaml.
Conf Bug#4941
Task #4207
Register a new runmode - DPDK. This enables a new flag on Suricata start
(--dpdk).
With the flag given, DPDK runmode is enabled.
Runmode loads the configuration and then initializes EAL.
If successful, it configures the physical NICs according to the configuration
file. After that, worker threads are initialized and then are in continuous
receive loop.
Unify handling of signature matches between various rule types and
between noalert and regular rules.
"noalert" sigs are added to the alert queue initially, but removed
from it after handling their actions. This way all actions are applied
from a single place.
Make sure flow drop and pass are mutually exclusive.
The above addresses issue with pass and drops not getting applied
correctly in various cases.
Bug: #4663
Bug: #4670
Allow a plugin to register itself as a capture source. This isn't that
much different than how current sources register, it just happens
a little later on during startup.
One "slot" is reserved for capture plugins, but multiple plugins
implementing a capture can be loaded. The --capture-plugin command
line option must be used to tell Suricata which plugin
to use.
This is still very much a work in progress, but can load
PF_RING as a capture plugin.
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.