Module imap 

IMAP (Internet Message Access Protocol) layer implementation.

Implements RFC 3501 IMAP4rev1 packet parsing as a zero-copy view into a packet buffer.

Protocol Overview

IMAP operates over TCP port 143 (993 for IMAPS). Unlike POP3, IMAP keeps messages on the server and supports folders, multiple clients, and partial message fetching.

Message Format

Client Command:

tag COMMAND [arguments]\r\n

Where tag is an alphanumeric identifier assigned by the client (e.g., “A001”).

Server Untagged Response (data/status):

* STATUS [data]\r\n
* NUMBER TYPE [data]\r\n

Server Tagged Response (command completion):

tag OK [text]\r\n
tag NO [text]\r\n
tag BAD [text]\r\n

Server Continuation Request:

+ [text]\r\n

Server Response Status Codes

Code	Meaning
OK	Command completed successfully
NO	Command failed
BAD	Protocol error
BYE	Server closing connection
PREAUTH	Already authenticated

Common IMAP Commands (RFC 3501)

Command	State	Description
CAPABILITY	Any	List server capabilities
NOOP	Any	No-op
LOGOUT	Any	End session
AUTHENTICATE	NonAuth	SASL authentication
LOGIN	NonAuth	Plaintext login
STARTTLS	NonAuth	TLS upgrade (RFC 2595)
SELECT	Auth	Select mailbox (read-write)
EXAMINE	Auth	Select mailbox (read-only)
CREATE	Auth	Create mailbox
DELETE	Auth	Delete mailbox
RENAME	Auth	Rename mailbox
SUBSCRIBE	Auth	Add to subscription list
UNSUBSCRIBE	Auth	Remove from subscription list
LIST	Auth	List mailboxes
LSUB	Auth	List subscribed mailboxes
STATUS	Auth	Request mailbox status
APPEND	Auth	Append message to mailbox
CHECK	Select	Checkpoint mailbox
CLOSE	Select	Close selected mailbox
EXPUNGE	Select	Remove deleted messages
SEARCH	Select	Search messages
FETCH	Select	Retrieve message data
STORE	Select	Alter message flags
COPY	Select	Copy messages to another mailbox
UID	Select	UID variant of COPY/FETCH/SEARCH/STORE

Re-exports

pub use builder::ImapBuilder;

Modules

builder

IMAP packet builder.

Structs

ImapLayer

A zero-copy view into an IMAP layer within a packet buffer.

Constants

CMD_APPEND

CMD_AUTHENTICATE

CMD_CAPABILITY

CMD_CHECK

CMD_CLOSE

CMD_COPY

CMD_CREATE

CMD_DELETE

CMD_EXAMINE

CMD_EXPUNGE

CMD_FETCH

CMD_LIST

CMD_LOGIN

CMD_LOGOUT

CMD_LSUB

CMD_NOOP

CMD_RENAME

CMD_SEARCH

CMD_SELECT

CMD_STARTTLS

CMD_STATUS

CMD_STORE

CMD_SUBSCRIBE

CMD_UID

CMD_UNSUBSCRIBE

IMAPS_PORT

IMAPS (over TLS) port.

IMAP_MIN_HEADER_LEN

Minimum IMAP payload size.

IMAP_PORT

IMAP standard port.

STATUS_BAD

STATUS_BYE

STATUS_NO

STATUS_OK

IMAP tagged response status strings.

STATUS_PREAUTH

Statics

IMAP_COMMANDS

IMAP_FIELD_NAMES

Field names for Python/generic access.

Functions

imap_show_fields

Returns a human-readable display of IMAP layer fields.

is_imap_payload

Returns true if buf looks like an IMAP payload.