app-layer.[ch], app-layer-detect-proto.[ch] and app-layer-parser.[ch].
Things addressed in this commit:
- Brings out a proper separation between protocol detection phase and the
parser phase.
- The dns app layer now is registered such that we don't use "dnstcp" and
"dnsudp" in the rules. A user who previously wrote a rule like this -
"alert dnstcp....." or
"alert dnsudp....."
would now have to use,
alert dns (ipproto:tcp;) or
alert udp (app-layer-protocol:dns;) or
alert ip (ipproto:udp; app-layer-protocol:dns;)
The same rules extend to other another such protocol, dcerpc.
- The app layer parser api now takes in the ipproto while registering
callbacks.
- The app inspection/detection engine also takes an ipproto.
- All app layer parser functions now take direction as STREAM_TOSERVER or
STREAM_TOCLIENT, as opposed to 0 or 1, which was taken by some of the
functions.
- FlowInitialize() and FlowRecycle() now resets proto to 0. This is
needed by unittests, which would try to clean the flow, and that would
call the api, AppLayerParserCleanupParserState(), which would try to
clean the app state, but the app layer now needs an ipproto to figure
out which api to internally call to clean the state, and if the ipproto
is 0, it would return without trying to clean the state.
- A lot of unittests are now updated where if they are using a flow and
they need to use the app layer, we would set a flow ipproto.
- The "app-layer" section in the yaml conf has also been updated as well.
In debug validation mode, it is required to call application layer
parsing and other functions with a lock on flow. This patch updates
the code to do so.
Now depth is kept in mind when we inspect chunks in client/server body.
This takes care of FPs originating from inspecting subsequent chunks that
match with depth, but shouldn't.
Improved accuracy, improved performance. Performance improvement
noticeable with http heavy traffic and ruleset.
A lot of other cosmetic changes carried out as well. Wrappers introduced
for a lot of app layer functions.
Failing dce unittests disabled. Will be reintroduced in the updated dce
engine.
Cross transaction matching taken care of. FPs emanating from these
matches have now disappeared. Double inspection of transactions taken
care of as well.
In some cases AppLayerTransactionGetInspectId can return -1, which is
now handled by all it's callers.
Improve logic of selecting which transactions are inspected by the various
HTTP keywords.
Introduce a separate FlowAddress structure for holding the ipv4 or ipv6 address
that doesn't have the family in it like the Address structure. Instead, the
family is stored in the flow as a flag: FLOW_IPV4 and FLOW_IPV6.
Add macro's to check the family, copy the address, etc.
Update many unittests to reflect these changes. Introduce unittest helper
functions for creating and initializing a flow and freeing it again.
On 64 bit this shrinks the flow with 8 bytes.
Removal of per flow 'aldata' array. It contained a ptr for each ALPROTO. Instead now we have 2 ptrs in the flow: alparser and alstate.
Various cleanups and dead code removal from the app layer API.
Should safe 100+ bytes memory per flow on 64 bit.
Updated lots of unittests to reflect these changes.
Victor Julien
Anoop Saldanha
Eric Leblond
Anoop Saldanha
Eileen Donlon