Replaces all patterns of SCLogError() followed by exit() with
FatalError(). Cocci script to do this:
@@
constant C;
constant char[] msg;
@@
- SCLogError(C,
+ FatalError(SC_ERR_FATAL,
msg);
- exit(EXIT_FAILURE);
Closes redmine ticket 3188.
This commit adds support for the Remote Framebuffer Protocol (RFB) as
used, for example, by various VNC implementations. It targets the
official versions 3.3, 3.7 and 3.8 of the protocol and provides logging
for the RFB handshake communication for now. Logged events include
endpoint versions, details of the security (i.e. authentication)
exchange as well as metadata about the image transfer parameters.
Detection is enabled using keywords for:
- rfb.name: Session name as sticky buffer
- rfb.sectype: Security type, e.g. VNC-style challenge-response
- rfb.secresult: Result of the security exchange, e.g. OK, FAIL, ...
The latter could be used, for example, to detect brute-force attempts
on open VNC servers, while the name could be used to map unwanted VNC
sessions to the desktop owners or machines.
We also ship example EVE-JSON output and keyword docs as part of the
Sphinx source for Suricata's RTD documentation.
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
The DCERPC UDP detection would misfire on DNS with transaction
ID 0x0400. This would happen as the protocol detection engine
gives preference to pattern based detection over probing parsers for
performance reasons.
This hack/workaround fixes this specific case by still running the
probing parser if DCERPC has been detected on UDP. The probing
parser result will take precedence.
Bug #2736.
This is a DHCP decoder and logger written in Rust. Unlike most
parsers, this one is stateless so responses are not matched
up to requests by Suricata. However, the output does contain
enough fields to match them up in post-processing.
Rules are included to alert of malformed or truncated options.
Add a new parser for Internet Key Exchange version (IKEv2), defined in
RFC 7296.
The IKEv2 parser itself is external. The embedded code includes the
parser state and associated variables, the state machine, and the
detection code.
The parser looks the first two messages of a connection, and analyzes
the client and server proposals to check the cryptographic parameters.
TFTP parsing and logging written in Rust.
Log on eve.json the type of request (read or write), the name of the file and
the mode.
Example of output:
"tftp":{"packet":"read","file":"rfc1350.txt","mode":"octet"}
Use expectation to be able to identify connections that are
ftp data. It parses the PASV response, STOR message and the
RETR message to provide extraction of files.
Implementation in Rust of FTP messages parsing is available.
Also this patch changes some var name prefixed by ssh to ftp.
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.
Since the parser now also does nfs2, the name nfs3 became confusing.
As it's still in beta, we can rename so this patch renames all 'nfs3'
logic to simply 'nfs'.
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.
Remove the 'StreamMsg' approach from the engine. In this approach the
stream engine would create a list of chunks for inspection by the
detection engine. There were several issues:
1. the messages had a fixed size, so blocks of data bigger than ~4k
would be cut into multiple messages
2. it lead to lots of data copying and unnecessary memory use
3. the StreamMsgs used a central pool
The Stream engine switched over to the streaming buffer API, which
means that the reassembled data is always available. This made the
StreamMsg approach even clunkier.
The new approach exposes the streaming buffer data to the detection
engine. It has to pay attention to an important issue though: packet
loss. The data may have gaps. The streaming buffer API tracks the
blocks of continuous data.
To access the data for inspection a callback approach is used. The
'StreamReassembleRaw' function is called with a callback and data.
This way it runs the MPM and individual rule inspection code. At
the end of each detection run the stream engine is notified that it
can move forward it's 'progress'.
The new Hyperscan 4.4 API provides a function to check for SSSE3
presence at runtime. This allows us to fall back to non-Hyperscan
matchers on systems without SSSE3 even when the suricata executable
is built with Hyperscan support. Addresses Redmine issue #2010.
Signed-off-by: Sascha Steinbiss <sascha@steinbiss.name>
Tested-by: Arturo Borrero Gonzalez <arturo@debian.org>
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.