Relevant RFCs

Collating a list of RFC documents and how they are relevant to K-9.

Email addresses

• RFC 3696 - Application Techniques for Checking and Transformation of Names
• RFC 5321 - Internet Message Format (and errata)

We obviously must support e-mail address formats

MIME

• RFC 2045 - Multipurpose Internet Mail Extensions (MIME) Part One: Format of Internet Message Bodies
• RFC 2046 - Multipurpose Internet Mail Extensions (MIME) Part Two: Media Types (obsoletes 1521, 1522, 1590)
• RFC 2047 - MIME (Multipurpose Internet Mail Extensions) Part Three: Message Header Extensions for Non-ASCII Text (obsoletes 1521, 1522, 1590)
• RFC 2048 - Multipurpose Internet Mail Extensions (MIME) Part Four: Registration Procedures
• RFC 2049 - Multipurpose Internet Mail Extensions (MIME) Part Five: Conformance Criteria and Examples
• RFC 2369 - The Use of URLs as Meta-Syntax for Core Mail List Commands and their Transport through Message Header Fields
• RFC 4021 - Registration of Mail and MIME Header Fields
• RFC 4288 - Media Type Specifications and Registration Procedures
• RFC 4289 - Multipurpose Internet Mail Extensions (MIME) Part Four: Registration Procedures (obsoletes 2048)

We receive and send MIME formatted e-mail

IMAP

• RFC 2177 - IMAP4 IDLE command
• RFC 3051 - INTERNET MESSAGE ACCESS PROTOCOL - VERSION 4rev1
• RFC 4551 - IMAP Extension for Conditional STORE Operation or Quick Flag Changes Resynchronization

See also: http://www.imapwiki.org/ImapRFCList for lots more

We support IMAP for receiving e-mail

SMTP

• RFC 281 - Simple Mail Transfer Protocol

We support SMTP for sending e-mail

POP3

• RFC 918 – POST OFFICE
• RFC 937 – POST OFFICE PROTOCOL – VERSION 2
• RFC 1081 – Post Office Protocol – Version 3
• RFC 1939 – Post Office Protocol – Version 3 (STD 53)
• RFC 1957 – Some Observations on Implementations of the Post Office Protocol (POP3)
• RFC 2195 – IMAP/POP AUTHorize Extension for Simple Challenge/Response
• RFC 2384 – POP URL Scheme
• RFC 2449 – POP3 Extension Mechanism
• RFC 2595 – Using TLS with IMAP, POP3 and ACAP
• RFC 3206 – The SYS and AUTH POP Response Codes
• RFC 5034 – The Post Office Protocol (POP3) Simple Authentication and Security Layer (SASL) Authentication Mechanism

We support POP3 for receiving e-mail

WebDAV

• RFC 2518 - HTTP Extensions for Distributed Authoring -- WEBDAV
• RFC 4918 - HTTP Extensions for Web Distributed Authoring and Versioning (WebDAV)

We support WebDAV for receiving e-mail

PGP/MIME

• RFC 1847 - Security Multiparts for MIME: Multipart/Signed and Multipart/Encrypted
• RFC 3156 - MIME Security with OpenPGP
• RFC 4880 - OpenPGP Message Format

We support OpenPGP for reading and writing encrypted e-mail

HTML

• RFC 2854 - The 'text/html' Media Type

While we don't parse HTML ourselves currently, we do want to support detecting HTML e-mail

URLs

• RFC 2368 - The mailto URL scheme

E-mails often contain URLs which we want to be able to parse and interpret usefully

TLS

• RFC 2854 - Transport Layer Security (TLS) Extensions

We support secure transmission of e-mail

SASL / CRAM / etc

• RFC 2195 - IMAP/POP AUTHorize Extension for Simple Challenge/Response
• RFC 4422 - Simple Authentication and Security Layer (SASL)
• SASL Mechanisms

We currently support this encryption protocol

GSSAPI / SCRAM / etc

• RFC 5802 - Salted Challenge Response Authentication Mechanism (SCRAM) SASL and GSS-API Mechanisms
• RFC 1508, RFC 1509, RFC 1964, RFC 2078, RFC 2222, RFC 2743, RFC 2744 - GSSAPI RFCs
• RFC 6749 - OAuth 2.0

We have requests for these encryption protocols

SMIME

• RFC 3369 - Cryptographic Message Syntax
• RFC 3370 - Cryptographic Message Syntax (CMS) Algorithms
• RFC 3850 - Secure/Multipurpose Internet Mail Extensions (S/MIME) Version 3.1 Certificate Handling
• RFC 3851 - Secure/Multipurpose Internet Mail Extensions (S/MIME) Version 3.1 Message Specification
• RFC 5751 - Secure/Multipurpose Internet Mail Extensions (S/MIME) Version 3.2 Message Specification

We want to receive and send S/MIME formatted e-mail in the future