This changeset makes changes to the TX logging path. Since the txn
is passed to the TX logger, the TX can be used directly instead of
through the TX id.
When Suricata picks up a flow it assumes the first packet is
toserver. In a perfect world without packet loss and where all
sessions neatly start after Suricata itself started, this would be
true. However, in reality we have to account for packet loss and
Suricata starting to get packets for flows already active be for
Suricata is (re)started.
The protocol records on the wire would often be able to tell us more
though. For example in SMB1 and SMB2 records there is a flag that
indicates whether the record is a request or a response. This patch
is enabling the procotol detection engine to utilize this information
to 'reverse' the flow.
There are three ways in which this is supported in this patch:
1. patterns for detection are registered per direction. If the proto
was not recognized in the traffic direction, and midstream is
enabled, the pattern set for the opposing direction is also
evaluated. If that matches, the flow is considered to be in the
wrong direction and is reversed.
2. probing parsers now have a way to feed back their understanding
of the flow direction. They are now passed the direction as
Suricata sees the traffic when calling the probing parsers. The
parser can then see if its own observation matches that, and
pass back it's own view to the caller.
3. a new pattern + probing parser set up: probing parsers can now
be registered with a pattern, so that when the pattern matches
the probing parser is called as well. The probing parser can
then provide the protocol detection engine with the direction
of the traffic.
The process of reversing takes a multi step approach as well:
a. reverse the current packets direction
b. reverse most of the flows direction sensitive flags
c. tag the flow as 'reversed'. This is because the 5 tuple is
*not* reversed, since it is immutable after the flows creation.
Most of the currently registered parsers benefit already:
- HTTP/SMTP/FTP/TLS patterns are registered per direction already
so they will benefit from the pattern midstream logic in (1)
above.
- the Rust based SMB parser uses a mix of pattern + probing parser
as described in (3) above.
- the NFS detection is purely done by probing parser and is updated
to consider the direction in that parser.
Other protocols, such as DNS, are still to do.
Ticket: #2572
Implement SMB app-layer parser for SMB1/2/3. Features:
- file extraction
- eve logging
- existing dce keyword support
- smb_share/smb_named_pipe keyword support (stickybuffers)
- auth meta data extraction (ntlmssp, kerberos5)
Also remove the now useless 'state' argument from the SetTxDetectState
calls. For those app-layer parsers that use a state == tx approach,
the state pointer is passed as tx.
Update app-layer parsers to remove the unused call and update the
modified call.
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.
To be able to add a transaction counter we will need a ThreadVars
in the AppLayerParserParse function.
This function is massively used in unittests
and this result in an long commit.
When DCERPC was wrapped in SMB it wasn't being initialized or
cleaned up properly. To fix, expose DCERPC initialization and
cleanup functions for use by the SMB application layer.
Redmine ticket:
https://redmine.openinfosecfoundation.org/issues/1708
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.
1. Proto detection
2. Parsers
For app layer protocols.
libhtp has now been moved to the section under app-layer.protocols.http,
but we still provide backward compatibility with older conf files.
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.
Also, update StateTransactionFree to take an u64 tx id, so it's
consistant with the rest of the engine.
To reflect these changes, AppLayerRegisterTransactionIdFuncs has
been renamed to AppLayerRegisterTxFreeFunc.
HTP, DNS, SMB, DCERPC parsers updated.
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
Victor Julien
Philippe Antoine
Jeff Lucovsky
Eric Leblond
Jason Ish
Giuseppe Longo
Ken Steele
Anoop Saldanha