Document transform_result and both forms of absent, the transforms
that can signal an error, how must_error and error_or treat bodies and
files inspected in parts, and the rule-load constraints. Note the
behavior changes in upgrade.rst: absent's mode string in the analyzer,
absent: or_else rejected after a transform that can fail, gunzip and
zlib_deflate keeping their input on failure, pcrexform's empty capture,
and from_base64's bytes handling.
Issue: 7313
Issue: 7114
Pygments 2.21 lexes "x < 0 or x > y" in Lua as a Lua 5.4 variable
attribute (e.g. "<const>"), producing an error token on the "0". Sphinx
reports this as a highlighting failure warning, and as the PDF build
treats warnings as errors, "make dist" fails while building the PDF.
Reorder the comparisons so the Lua example is lexed correctly. The logic
of the example is unchanged.
Add user-facing documentation for the xor transform's 'extract <nbytes>
<offset>' syntax and offset parameter in rules/transforms.rst.
Add a devguide section (devguide/extending/detect/transforms.rst)
covering the detection pipeline execution order, how transforms run
before detection-time keywords, and how xor reads key bytes directly
from the raw buffer at a specified position and width. Explains how
the engine deduplicates inspection buffers for rules with variable
keys at different buffer positions.
Issue: 8671
Extend the xor transform to accept a variable-position key using
the 'extract <nbytes> <offset>' syntax. The engine reads <nbytes> bytes
at buffer position <offset> at transform time.
The optional 'offset' parameter specifies where XOR decoding
starts in the buffer; bytes before that position are left unchanged.
Syntax:
xor:"<hex_key>"
xor:extract <nbytes> <offset>
xor:offset <N>,"<hex_key>"
xor:offset <N>,extract <nbytes> <offset>
Variable-key helpers (VariableKeyLocation, variable_key_bytes,
parse_key_location, strip_keyword_prefix) are imported from the new
varkey module.
The variable key bytes are copied out of the inspection buffer before
decoding, so an in-place transform cannot corrupt the key when the key
region overlaps the decoded range.
Issue: 8671
Issue: 8035
The `luaxform` transform doesn't support the `init` function. This
commit removes that from the example and clarifies how functions in the
Lua script are used.
Fixes https://redmine.openinfosecfoundation.org/issues/2689
Adds a new source file to handle this keyword.
And modifies documentation, Makefile, and registration accordingly.
url_decode decodes url-encoded data, ie replacing '+' with space
and '%HH' with its value.
Jeff Lucovsky
Jason Ish
Philippe Antoine
Eric Leblond
Philippe Antoine
Jeff Lucovsky
Victor Julien