Due to a logic error in AppLayerProtoDetectGetProtoByName invalid
protocols would not be detected as such. Instead of ALPROTO_UNKNOWN
ALPROTO_MAX was returned.
Bug #1329
Whenever DETECT_CONTENT_NOCASE is set for a BoyerMoore matcher, the
function BoyerMooreCtxToNocase() must be called. This call was missing
in AppLayerProtoDetectPMRegisterPattern().
Also created BoyerMooreNocaseCtxInit() that calls BoyerMooreCtxToNocase()
to make some code cleaner and safer.
Rather than converting the search string to lower case while searching,
convert it to lowercase during initialization.
Changes the Boyer Moore search API for take BmCtx
Change the API for BoyerMoore to take a BmCtx rather than the two parts that
are stored in the context. Which is how it is mostly used. This enforces
always calling BoyerMooreCtxToNocase() to convert to no-case.
Use CtxInit and CtxDeinit functions to create and destroy the context,
even in unit tests.
The direction specific masks were not used correctly. The toserver ones
were only used for 'dp' registrations, the toclient ones only for 'sp'.
The patch merges them.
If a flow matches both an 'sp' based PP registration and a 'dp' based,
until now we would only check the 'dp' one. This patch changes that. It
will inspect both.
Instead of the notion of toserver and toclient protocol detection, use
destination port and source port.
Independent of the data direction, the flow's port settings will be used
to find the correct probing parser, where we first try the dest port,
and if that fails the source port.
Update the configuration file format, where toserver is replaced by 'dp'
and toclient by 'sp'. Toserver is intrepreted as 'dp' and toclient as
'sp' for backwards compatibility.
Example for dns:
dns:
# memcaps. Globally and per flow/state.
#global-memcap: 16mb
#state-memcap: 512kb
# How many unreplied DNS requests are considered a flood.
# If the limit is reached, app-layer-event:dns.flooded; will match.
#request-flood: 500
tcp:
enabled: yes
detection-ports:
dp: 53
udp:
enabled: yes
detection-ports:
dp: 53
Like before, progress of protocol detection is tracked per flow direction.
Bug #1142.
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.
AppLayer Proto detection code uses a mix of pattern search and
"probing parsers". The pattern search validates potential matches
using a single pattern search algo. The code was using SpmSearch
for this, but this made it inefficient as it builds a BoyerMoore
context for each search. This lead to significant memory pressure,
especially on high speed/bandwidth boxes.
This patch switches the search calls to BoyerMoore and BoyerMoore-
Nocase directly. This can be done as the ctx' were available already.
Don't use FlowGetProtoMapping at runtime, use f->protomap instead.
Add safety check to make sure its value is within range, as it's
used to index an array.
Update unittests to initialized flows (somewhat).
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.
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.
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.
This patch fixes a compilation failure on Solaris. Compiler does
not support when a function returning void is used in return of
an other function returning void.
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.
When handling error case on SCMallog, SCCalloc or SCStrdup
we are in an unlikely case. This patch adds the unlikely()
expression to indicate this to gcc.
This patch has been obtained via coccinelle. The transformation
is the following:
@istested@
identifier x;
statement S1;
identifier func =~ "(SCMalloc|SCStrdup|SCCalloc)";
@@
x = func(...)
... when != x
- if (x == NULL) S1
+ if (unlikely(x == NULL)) S1
Jason Ish
Victor Julien
DIALLO David
Ken Steele
jeka
Anoop Saldanha
Eric Leblond
Last G
Anoop Saldanha