- test_credentials.c: NUL-terminate the overlong-line stack buffer before
make_tmp_file's strlen() (was a stack-buffer-overflow READ under ASan);
still exercises the overlong-rejection path.
- Add redacted protocol string variants (protocol_send_str_redacted /
receive + fd send_str_redacted/receive_str_redacted) and use them for the
daemon auth username/digest so --verbose / LOG_DEBUG_ALL never logs a
replayable credential while other protocol strings keep their debug trace.
- credentials_verify/gate: replace byte-wise-short-circuiting strcmp with a
fixed-length constant-time username compare (closes user-enumeration oracle);
update doc comment to match.
- read_secret_file: preserve password exact bytes (only strip trailing CR/LF)
and burn the stack line buffer; document the whitespace behavior.
- test_server_cli.c: note the parser zero-inits opts on failure.
- Add debug-level daemon test asserting the digest never appears under --verbose.
PROTOCOL_VERSION stays 2.15.0.