The unauthenticated stream ciphers (aes-*-cfb, aes-*-ctr, camellia-*-cfb,
chacha20, chacha20-ietf, salsa20) are gone from every build, together
with the SS_ENABLE_LEGACY option, the C++ stream codecs, their C test
oracle and the stream-only tests and configurations. A configuration
naming one of them, or RC4/table, now fails at startup with a message
pointing to an AEAD method, and test_cli checks that.
Shell completions list only the supported methods (and now include the
2022 ones), and the docs and the compatibility contract say the stream
ciphers were removed.
One engine (src/relay/tcp) for the four TCP relays: connections live in a
fixed pool owned through PoolPtr, handshake, cipher state and buffers are
inline, timeouts are intrusive deadline lists on one timer and DNS answers
come back through generation-checked handles. A full pool refuses new
connections and pauses accepting until a slot frees.
ss-tunnel is the first user; its hand-written relay callbacks are gone.
tests/tunnel_interop.py covers every method against ss-server and
shadowsocks-rust.