This commit adds
- Parser for the entropy keyword
- Calculation of content the Shannon entropy value
Issue: 4162
The entropy keyword syntax is the keyword entropy followed by options
and the entropy value for comparison.
The minimum entropy keyword specification is:
entropy: value <entropy-spec>
This results in the calculated entropy value being compared with
<entropy-spec> with the equality operator.
Calculated entropy values are between 0.0 and 8.0, inclusive.
A match occurs when the values and operator agree. This example matches
if the calculated and entropy value are the same.
When entropy keyword options are specified, all options and "value" must
be comma-separated. Options and value may be specified in any order.
Options have default values:
- bytes is equal to the current content length
- offset is 0
- comparison with value is equality
entropy: [bytes <byteval>] [offset <offsetval>] value <entropy-spec>
Using default values:
entropy: bytes 0, offset 0, value =<entropy-spec>
<entropy-spec> is: <operator> (see below) and a value, e.g., "< 4.1"
The following operators are available from the float crate:
- = (default): Match when calculated entropy value equals specified entropy value
- < Match when calculated entropy value is strictly less than specified entropy value
- <= Match when calculated entropy value is less than or equal to specified entropy value
- > Match when calculated entropy value is strictly greater than specified entropy value
- >= Match when calculated entropy value is greater than or equal to specified entropy value
- != Match when calculated entropy value is not equal to specified entropy value
- x-y Match when calculated entropy value is in the range, exclusive
- !x-y Match when calculated entropy value is not in the range, exclusive
Have bindgen generate bindings for app-layer-protos.h, then use the
generated definitions of AppProto/AppProtoEnum instead if defining
them ourselves.
This header was chosen as its used by Rust, and its a simple header
with no circular dependencies.
Ticket: #7341
In a recent warning reported by scan-build, datasets were found to be
using a blocking call in a critical section.
datasets.c:187:12: warning: Call to blocking function 'fgets' inside of critical section [unix.BlockInCriticalSection]
187 | while (fgets(line, (int)sizeof(line), fp) != NULL) {
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
datasets.c:292:12: warning: Call to blocking function 'fgets' inside of critical section [unix.BlockInCriticalSection]
292 | while (fgets(line, (int)sizeof(line), fp) != NULL) {
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
datasets.c:368:12: warning: Call to blocking function 'fgets' inside of critical section [unix.BlockInCriticalSection]
368 | while (fgets(line, (int)sizeof(line), fp) != NULL) {
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
datasets.c:442:12: warning: Call to blocking function 'fgets' inside of critical section [unix.BlockInCriticalSection]
442 | while (fgets(line, (int)sizeof(line), fp) != NULL) {
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
datasets.c:512:12: warning: Call to blocking function 'fgets' inside of critical section [unix.BlockInCriticalSection]
512 | while (fgets(line, (int)sizeof(line), fp) != NULL) {
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
5 warnings generated.
These calls are blocking in the multi tenant mode where several tenants
may be trying to load the same dataset in parallel.
In a single tenant mode, this operation is performed as a part of a
single thread before the engine startup.
In order to evade the warning and simplify the code, the initial file
reading is moved to Rust with this commit with a much simpler handling
of dataset and datarep.
Bug 7398
Ticket: 4863
On the way, convert some keywords to use the first-class integer
support.
And helpers for pure rust the support for multi-buffer.
Move the C unit tests about keyword mqtt.protocol_version
to unit tests for generic integer parsing, and test version 5
instead of testing twice version 3.
Also iterate all tx's messages for reason code as is done for other
keywords.
And allow detection on empty topics.
Add a new rule keyword "requires" that allows a rule to require specific
Suricata versions and/or Suricata features to be enabled.
Example:
requires: feature geoip, version >= 7.0.0, version < 8;
requires: version >= 7.0.3 < 8
requires: version >= 7.0.3 < 8 | >= 8.0.3
Feature: #5972
Co-authored-by: Philippe Antoine <pantoine@oisf.net>
This commit creates a module named "detect" for rule parsing logic. As
part of this commit, detect.rs is moved from its toplevel position into
the new module. Thus, use crate::detect::detect to refer to items within
detect.rs (instead of create::detect).
Ticket: 5077