This adds a signatures/http-body-match btest to verify how the signature
framework matches HTTP body in requests and responses.
It currently fails because the 'http-request-body' and 'http-reply-body'
clauses never match anything when there is a '$' in their regular
expressions.
The other pattern clauses such as the 'payload' clause do not suffer
from that restriction and it is not documented as a limitation of HTTP
body pattern clauses either, so it is probably a bug.
The "http-body-match" btest shows that without a fix any signatures
which ends with a '$' in a http-request-body or http-reply-body rule
will never raise a signature_match() event, and that signatures which do
not end with a '$' cannot distinguish an HTTP body prefixed by the
matching pattern (ex: ABCD) from an HTTP body consisting entirely of the
matching pattern (ex: AB).
Test cases by source port:
- 13579:
- GET without body, plain res body (CD, only)
- 13578:
- GET without body, plain res body (CDEF, prefix)
- 24680:
- POST plain req body (AB, only), plain res body (CD, only)
- 24681:
- POST plain req body (ABCD, prefix), plain res body (CDEF, prefix)
- 24682:
- POST gzipped req body (AB, only), gzipped res body (CD, only)
- POST plain req body (CD, only), plain res body (EF, only)
- 33210:
- POST multipart plain req body (AB;CD;EF, prefix)
- plain res body (CD, only)
- 33211:
- POST multipart plain req body (ABCD;EF, prefix)
- plain res body (CDEF, prefix)
- 34527:
- POST chunked gzipped req body (AB, only)
- chunked gzipped res body (CD, only)
- 34528:
- POST chunked gzipped req body (ABCD, prefix)
- chunked gzipped res body (CDEF, prefix)
The tests with source ports 24680, 24682 and 34527 should
match the signature http_request_body_AB_only and the signature
http_request_body_AB_prefix, but they only match the latter.
The tests with source ports 13579, 24680, 24682, 33210 and 34527 should
match the signature http_response_body_CD_only and the signature
http_response_body_CD_prefix, but they only match the latter.
The tests with source ports 24680, 24681, 33210 and 33211 show how the
http_request_body_AB_then_CD signature with two http-request-body
conditions match either on one or multiple requests (documented
behaviour).
The test cases with other source ports show where the
http_request_body_AB_only and http_response_body_CD_only signatures
should not match because their bodies include more than the searched
patterns.