Expand description

This section documents rustls itself: what protocol features are and are not implemented.

Current features

  • TLS1.2 and TLS1.3.
  • ECDSA, Ed25519 or RSA server authentication by clients.
  • ECDSA, Ed25519 or RSA server authentication by servers.
  • Forward secrecy using ECDHE; with curve25519, nistp256 or nistp384 curves.
  • AES128-GCM and AES256-GCM bulk encryption, with safe nonces.
  • ChaCha20-Poly1305 bulk encryption (RFC7905).
  • ALPN support.
  • SNI support.
  • Tunable MTU to make TLS messages match size of underlying transport.
  • Optional use of vectored IO to minimise system calls.
  • TLS1.2 session resumption.
  • TLS1.2 resumption via tickets (RFC5077).
  • TLS1.3 resumption via tickets or session storage.
  • TLS1.3 0-RTT data for clients.
  • Client authentication by clients.
  • Client authentication by servers.
  • Extended master secret support (RFC7627).
  • Exporters (RFC5705).
  • OCSP stapling by servers.
  • SCT stapling by servers.
  • SCT verification by clients.

Possible future features

  • PSK support.
  • OCSP verification by clients.
  • Certificate pinning.

Non-features

For reasons explained in the other sections of this manual, rustls does not and will not support:

  • SSL1, SSL2, SSL3, TLS1 or TLS1.1.
  • RC4.
  • DES or triple DES.
  • EXPORT ciphersuites.
  • MAC-then-encrypt ciphersuites.
  • Ciphersuites without forward secrecy.
  • Renegotiation.
  • Kerberos.
  • Compression.
  • Discrete-log Diffie-Hellman.
  • Automatic protocol version downgrade.