Victor Julien [Mon, 24 Jan 2022 22:30:51 +0000 (23:30 +0100)]
detect/frames: fix crash when parsing bad rule
Indexing of Signature::init_data::smlists would fail for a rule that
used a frame w/o content, as the array would only be expanded when
adding a content. Adding a check to see if there list id is in bounds
is an implicit check for the "no content" case.
smb/dce_iface: avoid deleting current ifaces from state
The smb dce_iface keyword must match for all those dcerpc requests
and responses sent in the context of the given interface. They are
not matching as the current bind interfaces are deleted by any
non bind message.
The smb dce_iface keyword must match for all those dcerpc requests and
responses sent in the context of the given interface. They are not
matching because in rs_smb_tx_get_dce_iface, x.req_cmd is erroneously
compared with 1. Fix this by comparing with DCERPC_TYPE_REQUEST instead.
The smb dce_opnum matches all the opnums that are higher that the
indicated opnum. This is due the range comparison if was put in the
exact comparison context, and in case the opnum doesn't match exactly,
then the range comparison is triggered (the upper limit is always true).
Move the erroneus if to the outer context, as else option of the block
checks if comparison should be exact or range.
The smb dce_opnum keyword doesn't match the dcerpc requests/responses.
This occurs because in the rs_smb_tx_match_dce_opnum function, the
x.req_cmd is matched against the erroneous code 1. Fix this by using
DCERPC_TYPE_REQUEST for the comparison instead.
dcerpc: avoid delete the rpc state interface context
The bug:
The dcerpc dce_iface keyword just match the packet following the bind. Only the
next request after the rpc is sent will match. However the expected behaviour it
that all the rpc requests/responses sent under the context of the given
interface would match.
In the Open Group c706 the following is indicated:
In 2.2.1 Binding-related Operations, indicates that one category of binding
operations are those that "operations that establish internal call routing
information for the server." (The other are to establish the protocol which is
not relevant here). And the following statement can be found:
Operations in the second category establish a set of mappings that the server
can use to route calls internally to the appropriate manager routine. This
routing is based on the interface and version, operation and any object
requested by the call.
It indicates that server routes (to call methods) are based on the operation,
interface and object.
- Operation: To indicate the method to call, and operation number is
specified as indicated in the second step of 2.3.3.2 (Client
Binding Steps).
- Interface: An interface is a set of remotely callable operations offered by a
server and invokable by clients. (2.1.1.1)
- Object: Is the manager that implements the interface, as stated in section
Interface and Manager Selection of 2.3.3.3. It is not mandatory, can
be nil.
To call a method, a client must send a request message as defined in 2.6.4.9,
that contains these identifiers:
- opnum: The opnum field identifies the operation being invoked within the
interface.
- p_cont_id (Context ID in Wireshark): The p_cont_id field holds a presentation
context identifier that identifies the
data representation and interface, as
defined in 12.6.3.4 (Context Identifiers).
- object: The object field is contained if the PFC_OBJECT_UUID is set. (Could be
interesting to create a keyword dce_object for matching this UUID)
Therefore, to get the correct method to invoke, the server must map the context
to the correct interface. This is negotiated by the bind request
Interfaces are first negotiated using the bind message (12.6.4.3), contained in
the p_context_elem array. Then they are accepted or rejected using the bind_ack
message (12.6.4.4).
Once these contexts are established, both client and server can use the context
id, which is the index of the p_context_elem array, to refer the interface they
are using.
Moreover, in the middle of the connection, the context can be changed with the
alter_context message.
This is way suricata shouldn't delete the bindack attribute, that contains
the contexts, used by match_backuuid. This is the only way to know the interface
a request message is referring to.
Pgsql was using bitwise operations to assign password output config to
its context flags, but mixing that with logic negation of the default
value, resulting in the expressions having a constant value as result.
Jason Ish [Thu, 20 Jan 2022 18:08:33 +0000 (12:08 -0600)]
logging: change ownership of application log if needed
When running with privilege dropping, the application log file
is opened before privileges are dropped resulting in Suricata
failing to re-open the file for file rotation.
If needed, chown the application to the run-as user/group after
opening.
Jason Ish [Thu, 20 Jan 2022 17:40:24 +0000 (11:40 -0600)]
startup: initialize run as user info sooner
Initialize the run-as user info after loading the config, but
before setting up logging (previously it was done while initializing
signal handlers). This will allow the log file to be given the
correct permissions if Suricata is configured to run as a non-root
user.
This rule will only inspect the data portion of SMB1 frames. It will not affect
any other protocol, and it won't need special patterns to "search" for the
SMB1 frame in the raw stream.
Victor Julien [Fri, 3 Dec 2021 06:40:56 +0000 (07:40 +0100)]
app/frames: initial support
The idea of stream frames is that the applayer parsers can tag PDUs and
other arbitrary frames in the stream while parsing. These frames can then
be inspected from the rule language. This will allow rules that are more
precise and less costly.
The frames are stored per direction in the `AppLayerParserState` and will only
be initialized when actual frames are in use. The per direction storage has a
fixed size static portion and dynamic support for a larger number. This is done
for effeciency.
When the Stream Buffer slides, frames are updated as they use offsets relative
to the stream. A negative offset is used for frames that started before the
current window.
Frames have events to inspect/log parser errors that don't fit the TX model.
Frame id starts at 1. So implementations can keep track of frame ids where 0
is not set.
Frames affect TCP window sliding. The frames keep a "left edge" which
signifies how much data to keep for frames that are still in progress.
Victor Julien [Thu, 13 Jan 2022 11:13:43 +0000 (12:13 +0100)]
stream: fix stream pruning being too aggressive
Pruning of StreamBufferBlocks could remove blocks that fell entirely
after the target offset due to a logic error. This could lead to data
being evicted that was still meant to be processed in theapp-layer
parsers.
Jeff Lucovsky [Sun, 26 Dec 2021 15:22:34 +0000 (10:22 -0500)]
detect: Avoid recomputing ntohl() in addr match
This commit makes a small optimization when comparing IPv4 and IPv6
addresses by making the host order value invariant and calculating the
value once, before entering the loop.
projects / thirdparty / suricata.git / log
