Crate rusmes_imap 

IMAP protocol implementation for RusMES

This crate provides a full-featured, RFC-compliant IMAP server implementation built on Tokio for asynchronous I/O.

RFC Compliance

• RFC 9051 (IMAP4rev2) / RFC 3501 (IMAP4rev1): Core IMAP protocol
• RFC 7162 (CONDSTORE / QRESYNC): Efficient mailbox synchronization with MODSEQ tracking, CHANGEDSINCE/UNCHANGEDSINCE modifiers, and VANISHED responses
• RFC 6154 (SPECIAL-USE): \Drafts, \Sent, \Trash, \Junk, etc.
• RFC 4315 (UIDPLUS): APPENDUID and COPYUID response codes
• RFC 6851 (MOVE): MOVE command and COPYUID response for moves
• RFC 2177 (IDLE): Server-push idle notification
• RFC 2342 (NAMESPACE): Personal, shared, and other-users namespaces
• RFC 2449 (CAPABILITY): Capability advertisement

Supported Commands

Not Authenticated State

• CAPABILITY — List server capabilities
• NOOP — No-operation (keep-alive)
• LOGOUT — Disconnect
• LOGIN user password — Plain-text authentication
• AUTHENTICATE mechanism — SASL authentication (PLAIN, LOGIN, CRAM-MD5, SCRAM-SHA-256, XOAUTH2)

Authenticated State

• SELECT mailbox — Open mailbox read-write
• EXAMINE mailbox — Open mailbox read-only
• CREATE mailbox — Create new mailbox (with optional SPECIAL-USE flag)
• DELETE mailbox — Delete a mailbox
• RENAME old new — Rename a mailbox
• SUBSCRIBE mailbox — Subscribe to a mailbox
• UNSUBSCRIBE mailbox — Unsubscribe from a mailbox
• LIST reference mailbox — List mailboxes matching a pattern
• LSUB reference mailbox — List subscribed mailboxes matching a pattern
• NAMESPACE — Query server namespaces
• APPEND mailbox ... — Append a message to a mailbox

Selected State

• FETCH sequence items — Retrieve message data
• STORE sequence flags — Modify message flags
• SEARCH criteria — Search for messages
• COPY sequence mailbox — Copy messages to another mailbox
• MOVE sequence mailbox — Move messages to another mailbox
• EXPUNGE — Permanently delete messages with \Deleted flag
• CLOSE — Implicit expunge and deselect
• IDLE — Enter server-push idle mode (RFC 2177)
• UID FETCH/STORE/SEARCH/COPY/MOVE/EXPUNGE — UID-based variants

Modules

• authenticate: SASL multi-step authentication (PLAIN, LOGIN, CRAM-MD5, SCRAM-SHA-256, XOAUTH2)
• command: IMAP command enumeration and types
• condstore: CONDSTORE extension — MODSEQ, CHANGEDSINCE, UNCHANGEDSINCE
• config: Server configuration (ImapConfig)
• handler: Command dispatcher (HandlerContext, handle_command)
• handler_auth: LOGIN and LOGOUT handlers
• handler_mailbox: Mailbox-level command handlers
• handler_message: Message-level command handlers (FETCH, STORE, etc.)
• mailbox_watcher: Watches for mailbox changes to support IDLE push notifications
• parser: IMAP command-line parser including APPEND literal handling
• qresync: QRESYNC extension — UID range sets, vanished responses
• response: IMAP response formatting (tagged OK/NO/BAD, untagged *)
• server: Async TCP listener accepting IMAP connections
• session: Per-connection state machine (NotAuthenticated → Authenticated → Selected ↔ Idle → Logout)
• special_use: SPECIAL-USE mailbox attributes (RFC 6154)

Security

All random challenge material (CRAM-MD5, SCRAM nonces) is generated via getrandom for cryptographic-quality entropy. In production deployments, TLS should be enabled to protect LOGIN/PLAIN credentials in transit.

Re-exports

pub use authenticate::create_default_sasl_server;

pub use authenticate::handle_authenticate;

pub use authenticate::handle_authenticate_continue;

pub use authenticate::parse_authenticate_args;

pub use authenticate::AuthenticateContext;

pub use authenticate::AuthenticateState;

pub use command::ImapCommand;

pub use command::StoreMode;

pub use condstore::ChangedSince;

pub use condstore::CondStoreError;

pub use condstore::CondStoreResponse;

pub use condstore::CondStoreState;

pub use condstore::CondStoreStatus;

pub use condstore::UnchangedSince;

pub use config::ImapConfig;

pub use handler::handle_command;

pub use handler::HandlerContext;

pub use mailbox_watcher::MailboxChanges;

pub use mailbox_watcher::MailboxWatcher;

pub use parser::has_literal;

pub use parser::parse_append_command;

pub use parser::parse_command;

pub use parser::LiteralType;

pub use qresync::QResyncError;

pub use qresync::QResyncLogic;

pub use qresync::QResyncParams;

pub use qresync::QResyncState;

pub use qresync::SeqMatchData;

pub use qresync::UidRange;

pub use qresync::UidSet;

pub use qresync::VanishedResponse;

pub use response::ImapResponse;

pub use server::ImapServer;

pub use session::ImapSession;

pub use session::ImapState;

pub use session::MailboxSnapshot;

pub use special_use::format_capability_response;

pub use special_use::format_list_extended;

pub use special_use::parse_create_special_use;

pub use special_use::suggest_special_use;

pub use special_use::validate_special_use_flags;

pub use special_use::SpecialUse;

pub use special_use::SpecialUseError;

pub use special_use::SpecialUseFlags;

pub use special_use::LIST_EXTENDED_CAPABILITY;

pub use special_use::SPECIAL_USE_CAPABILITY;

Modules

authenticate

IMAP AUTHENTICATE command implementation with SASL integration

command

IMAP command types

condstore

IMAP CONDSTORE Extension - RFC 7162

config

IMAP server configuration

handler

IMAP command handler dispatcher

handler_auth

IMAP authentication command handlers (LOGIN, LOGOUT)

handler_mailbox

IMAP mailbox command handlers

handler_message

IMAP message command handlers

mailbox_watcher

Mailbox change detection for IDLE support

parser

IMAP command parser

qresync

IMAP QRESYNC Extension - RFC 7162

response

IMAP response types

server

IMAP server implementation

session

IMAP session state machine

special_use

IMAP SPECIAL-USE extension (RFC 6154)