stacklok / toolhive / 29408585325

68%

Build Type

push

github

Committed by web-flow

Commit Message

Stop SSE filter from leaking tools/list on undecodable lines (#5304)

* Stop SSE filter from leaking tools/list on undecodable lines

processSSEResponse used to write the entire raw upstream payload and
return whenever a single SSE data line failed jsonrpc2.DecodeMessage or
decoded to a non-Response message (e.g. a notifications/* frame). On a
tools/list reply that meant every subsequent data line, including the
real Response, reached the client unfiltered, silently bypassing the
cedar authorization filter and producing the superfluous WriteHeader
warning at response_filter.go:191.

Treat undecodable or non-Response data lines as pass-through for that
line only: fall through to the existing line writer instead of dumping
rawResponse. The explicit WriteHeader calls go away with them, which
also removes the double-header warning that surfaced the bug. Skipped
filtering on tools/list now emits a WARN so future bypasses are
visible in audit logs.

Adds a table-driven regression test covering both branches (decode
error and non-Response). It fails on the old code with the unfiltered
admin_tool entry reaching the recorder.

Closes #5257

* Broaden SSE filter logging and tests across list methods

Address review feedback on #5304:

The WARN log paths in processSSEResponse were gated on the
tools/list method, but the underlying bypass applies to every
method routed through requiresResponseFiltering (tools/list,
prompts/list, resources/list, find_tool). Drop the gating so
the WARN fires for any of them.

The regression test only exercised tools/list. Restructure it
into a method-by-preceding-line table so the same notification
and undecodable line cases run against prompts/list and
resources/list as well. Verified the WARN now logs for all
three methods and the unauthorized entry never reaches the
recorder.

* authz: drop disguised result frames and fix SSE line termination

A non-Response SSE frame carrying both a method field and a result (for
example notifi... (continued)

Coverage Stats

67 of 79 new or added lines in 1 file covered. (84.81%)

14 existing lines in 4 files now uncovered.

73504 of 108076 relevant lines covered (68.01%)

64.37 hits per line