SCRAM-SHA-1(-PLUS) + SCRAM-SHA-256(-PLUS) + SCRAM-SHA-512(-PLUS) + SCRAM-SHA3-512(-PLUS) supports

Dear @ruby team,

In first, I wish you a Happy New Year!

Can you add supports of :

• SCRAM-SHA-1
• SCRAM-SHA-1-PLUS
• SCRAM-SHA-256
• SCRAM-SHA-256-PLUS
• SCRAM-SHA-512
• SCRAM-SHA-512-PLUS
• SCRAM-SHA3-512
• SCRAM-SHA3-512-PLUS

You can add too:

• SCRAM-SHA-224
• SCRAM-SHA-224-PLUS
• SCRAM-SHA-384
• SCRAM-SHA-384-PLUS

"When using the SASL SCRAM mechanism, the SCRAM-SHA-256-PLUS variant SHOULD be preferred over the SCRAM-SHA-256 variant, and SHA-256 variants [RFC7677] SHOULD be preferred over SHA-1 variants [RFC5802]".

• SCRAM-SHA-1(-PLUS):
  -- https://tools.ietf.org/html/rfc5802
  -- https://tools.ietf.org/html/rfc6120

• SCRAM-SHA-256(-PLUS):
  -- https://tools.ietf.org/html/rfc7677 since 2015-11-02
  -- https://tools.ietf.org/html/rfc8600 since 2019-06-21: https://mailarchive.ietf.org/arch/msg/ietf-announce/suJMmeMhuAOmGn_PJYgX5Vm8lNA

• SCRAM-SHA-512(-PLUS):
  -- https://tools.ietf.org/html/draft-melnikov-scram-sha-512

• SCRAM-SHA3-512(-PLUS):
  -- https://tools.ietf.org/html/draft-melnikov-scram-sha3-512

https://xmpp.org/extensions/inbox/hash-recommendations.html

-PLUS variants:

• RFC5056: On the Use of Channel Bindings to Secure Channels: https://tools.ietf.org/html/rfc5056
• RFC5929: Channel Bindings for TLS: https://tools.ietf.org/html/rfc5929
• Channel-Binding Types: https://www.iana.org/assignments/channel-binding-types/channel-binding-types.xhtml
• RFC 9266: Channel Bindings for TLS 1.3: https://tools.ietf.org/html/rfc9266

IMAP:

• RFC9051: Internet Message Access Protocol (IMAP) - Version 4rev2: https://tools.ietf.org/html/rfc9051

LDAP:

• RFC5803: Lightweight Directory Access Protocol (LDAP) Schema for Storing Salted: Challenge Response Authentication Mechanism (SCRAM) Secrets: https://tools.ietf.org/html/rfc5803

HTTP:

• RFC7804: Salted Challenge Response HTTP Authentication Mechanism: https://tools.ietf.org/html/rfc7804

2FA:

• Extensions to Salted Challenge Response (SCRAM) for 2 factor authentication: https://tools.ietf.org/html/draft-melnikov-scram-2fa

IANA:

• Simple Authentication and Security Layer (SASL) Mechanisms: https://www.iana.org/assignments/sasl-mechanisms/sasl-mechanisms.xhtml

Linked to:

• https://github.com/scram-xmpp/info/issues/1

Start by inspecting net-smtp's existing authentication entry points and tests to determine how SMTP mechanisms are registered and negotiated. Compare the current implementation with the listed SCRAM specifications; done means the requested SCRAM variants, including channel-binding variants where supported, are implemented and covered by tests.