This patch provides a working expectation system. This will allow
suricata to have a way to identify parallel connections opened by
a protocol such as FTP.
Expectation are a chained list and there is a cleaning by timeout
of the entries.
This patch also defined a counter of expectations that is also
used to check if we need to query IPPairs. This way we only query
the IPPairs store if we have an expectation.
Add API calls to upgrade to TLS or to request a protocol change
without a specific protocol expectation.
If the HTTP CONNECT session includes a port on the url, use that to
look up the probing parser during protocol detection. Solves a
missed detection of a SSLv2 session that upgrades to TLSv1. SSLv2
relies on the probing parser which is limited to certain ports.
In case of STARTTLS in SMTP and FTP, the port is hardcoded to 443.
A new event APPLAYER_UNEXPECTED_PROTOCOL is set if there was a
mismatch.
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.
When registering a probing parser allow to_server and
to_client parsers to be registered. Previously the
probing parser may be called for both directions which
in some cases works OK, but in others can cause
the to_client side to be detected as failed.
The probing parser registration function
AppLayerProtoDetectPPParseConfPorts was a void, meaning it would
give no feedback to the registering protocol implementation. If a
config was missing, it would just give up.
This patch changes it to return a bool. 0 if no config was found,
1 if a config was found.
This allows the caller to setup a default case.
Remove unnecessay inlining.
Rename functions with wrong naming scheme. E.g. AllocAppLayer.. instead
of AppLayer..Alloc.
Use AppProto instead of uint16_t.
Convert u16 ipproto cases to u8.
For AppLayerThreadCtx, AppLayerParserState, AppLayerParserThreadCtx
and AppLayerProtoDetectThreadCtx, use opaque pointers instead of
void pointers.
AppLayerParserState is declared in flow.h as it's part of the Flow
structure.
AppLayerThreadCtx is declared in decode.h, as it's part of the
DecodeThreadVars structure.
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.
If a session only has data in one direction, like ftp data sessions,
protocol detection will only run in one direction. This led to a
situation where reassembly would hold all the segments as proto
detection was never flagged as complete.
This patch introduces a limit for protocol detection in this case.
If the limit is reached, detection will give up.
In case of recursive call to protocol detection from within protocol
detection, and the recursively invoked stream still hasn't been ack'ed
yet, protocol detection doesn't take place. In such cases we will end up
still calling the app layer with the wrong direction data. Introduce a
check to not call app layer with wrong direction data.
When sockets are re-used reset all relevant vars correctly.
This commit fixes a bug where we were not reseting app proto detection
vars.
While fixing #989, we discovered some other bugs which have also been
fixed, or rather some features which are now updated. One of the feature
update being if we recieve wrong direction data first, we don't reset the
protocol values for the flow. We let the flow retain the detected
values.
Unittests have been modified to accomodate the above change.
PM and PP phase.
Replace the areas of the code that would otherwise rely on setting/reading
these flags with these macros.
Other minor tweaks to some api calls.
First version of a simple pattern based L7 proto detection engine. Currently just works by matching a single pattern in the initial data. Implemented HTTP, SSL, MSN, JABBER, SMTP and a few more.
Couple of pattern matcher cleanups.
Eric Leblond
Victor Julien
Mats Klepsland
Jason Ish
Anoop Saldanha
Anoop Saldanha
Pablo Rincon
Gurvinder Singh
William Metcalf
Brian Rectanus