Remove every bare `#[allow(dead_code)]` in io-core, object-capacity, targets, rio, and scanner. Each allow was stripped first and clippy was then asked which ones the compiler actually missed, so the verdicts rest on the diagnostic rather than on inspection.
23 were inert: they sat on `pub fn`s inside `pub mod`s, where `dead_code` does not apply, or on scanner integration-test helpers that the tests in the same file do call.
The remaining 3 are in rio's private `compress_index` module and the code behind them is deleted rather than annotated. `remove_index_headers` is dead and also wrong — after skipping the 4-byte chunk header it matches against `S2_INDEX_TRAILER` where `S2_INDEX_HEADER` sits, so it returns `None` for every well-formed index; rio-v2 carries the correct equivalent that is actually in use. `restore_index_headers` is its unreachable counterpart, likewise duplicated live in rio-v2. `Index::reset` is a private method with no caller.
Refs backlog#1823
extract_params_header copied every request/response header verbatim into
the maps that feed audit entries (requestQuery/responseHeader) and
notification events (req_params). Sensitive headers such as
Authorization and X-Amz-Security-Token were serialized in plaintext and
forwarded to external sinks (webhook/kafka/file), leaking long-lived
credentials.
Redact credential-bearing headers at this single chokepoint: the header
name is kept for correlation, but its value is replaced with the shared
REDACTED_SECRET placeholder. A case-insensitive sensitive-header list
covers authorization, x-amz-security-token, x-amz-content-sha256,
cookie, and set-cookie. Non-sensitive headers keep their existing
behavior.
Refs: https://github.com/rustfs/backlog/issues/963
Zhengchao An