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.
Remove all flags indicating the buffer type. They were only used
at parse time.
Because of this the DetectPcreData_ structure could shrink to 32
bytes.
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.
sigs(priority wise) inside staging.
Previously we would assign signums before sig ordering, and hence the
order didn't actually reflect the order of the sig in the
sig_list(assuming sig reordering changed the sig_list). Staging would
use the old sig_nums to decide the priority of sigs.
2. Fix sig ordering for flowvar, flowbits, flowint, pktvar sigs. We have
introduced a new priority to treat sigs with set + read as lower
priority compared to set only sigs.
3. Previously we treated sigs with a "priority(keyword)" > another sig's
priority, as a sig with greater priority than the later. We have
reversed it. Now the sig priority ordering is 1,2,.etc. Updated
sigordering unittests to reflect the same.
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.
Bug #802
Flowvars are set from pcre, and lock the flow when being set. However
when HTTP buffers were inspected, flow was already locked: deadlock.
This patch introduces a post-match list in the detection engine thread
ctx, where store candidates are kept. Then a post-match function is used
to finalize the storing if the rule matches.
Solves the deadlock and brings the handling of flowvars more in line
with flowbits and flowints.
Previously we would have forced all users to use nocase with http_host
keywords(since the hostname buffer is lowercase).
We now error out on sigs that has nocase set with http_host set. Also if
the http_host pattern or http_host pcre has an uppercase character set, we
invalidate such sigs. Unittests also updated to reflect the above change.
The output of the list-keyword is modified to include the url to
the keyword documentation when this is available. All documented
keywords should have their link set.
list-keyword can be used with an optional value:
no option or short: display list of keywords
csv: display a csv output on info an all keywords
all: display a human readable output of keywords info
$KWD: display the info about one keyword.
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