Add optional one-way TLS to the MFC server (server/2015Remote) so the device
port can serve both TLS clients and legacy plaintext clients on the same port,
mirroring the Go server.
Server: on a connection's first bytes, sniff for a TLS ClientHello (0x16 0x03
+ handshake type 0x01). When [tls] Enabled=1 and the identity loads, hand the
socket to a short-lived blocking handshake thread (Option A) running Schannel
AcceptSecurityContext, then decrypt on recv and encrypt on send; plaintext
connections replay the sniffed bytes straight into the existing parse path, so
the plaintext code path is otherwise unchanged. The identity is loaded once
from [tls] CertPath/KeyPath as PEM + CNG (PKCS#8) — the same key pair the Go
server uses — and a missing [tls] section, an empty value, or a load failure
leaves plaintext serving intact and fail-closes any TLS ClientHello.
Also fix two transport-reliability bugs that surfaced end-to-end:
- send path: encrypt only the freshly appended plaintext tail and post a
single IOWrite wake-up guarded by a bSendPending flag, so back-to-back small
sends (terminal resize -> COMMAND_NEXT -> resize) no longer run concurrent
WSASends over the same mutable buffer (client saw DecryptMessage failures,
with WSAGetLastError() = 6001 / ERROR_DECRYPTION_FAILED);
- client Recv: keep the handshake's unconsumed tail bytes in m_raw and drain
them before the next recv, and log the real SECURITY_STATUS on
DecryptMessage failure instead of the stale Winsock error.
Co-Authored-By: deepseek-v4-pro
Add optional one-way TLS on the device port (6543), enabled per client via a
pinned trust anchor, so new clients encrypt their transport while legacy
plaintext clients keep working unchanged.
Server (server/go): sniff each accepted connection and wrap TLS peers
(ClientHello 0x16 0x03 + handshake type 0x01) in crypto/tls with MinVersion
TLS 1.2; everything else stays on the plaintext path. TLS is enabled only when
both YAMA_TLS_CERT and YAMA_TLS_KEY are set, and a cert/key load failure fails
startup loudly rather than silently serving plaintext.
Client (client/, Windows): Schannel one-way TLS. When the trust anchor is
present — registry value Software\<exehash>\settings\tls_cert (REG_SZ holding
the PEM), with fallback to settings.ini [settings] tls_cert or yama-ca.pem
beside the exe — every outbound connection (main + sub-connections) completes
a TLS 1.2 handshake before the app protocol and is strictly pinned to that
anchor via a chain engine with hExclusiveRoot; any handshake/cert failure is
fail-closed (no plaintext downgrade). Send uses EncryptMessage; Recv uses
DecryptMessage and reads plaintext from the stream-mode DATA segment (bufs[1])
rather than the record header.
Co-Authored-By: deepseek-v4-pro
