| Internet-Draft | Abbreviated Title | February 2025 |
| Melnikov | Expires 25 August 2025 | [Page] |
While EMAILCORE working group was working on update to SMTP specification, it became clear that existing SMTP related registries need to be restructured and existing entries need to be updated. This document describes these tasks.¶
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While EMAILCORE working group was working on update to SMTP specification [I-D.ietf-emailcore-rfc5321bis], it became clear that existing SMTP related registries need to be restructured and some existing entries need to be updated. This document describes these tasks, assuming IANA actions specified in [I-D.ietf-emailcore-rfc5321bis] were already performed.¶
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here.¶
Updates to the "Simple Mail Transfer Protocol (SMTP) Service Extensions" registry are described as an ordered list of steps that should be performed sequentually. Each step is described by a subsection of this section.¶
IANA is requested to change values of the "References" field for "EXPN" and "HELP" extensions to [I-D.ietf-emailcore-rfc5321bis]. The "References" field values for "SEND", "SOML", "SAML" and "TURN" remain unchanged, as they were obsoleted and there are no newer reference than RFC 821.¶
IANA is requested to update the following values in this field:¶
The value corresponding to the DELIVERBY extension should be changed to "A comma separated list of options (optional)".¶
The value corresponding to the FUTURERELEASE extension should be changed to "max-future-release-interval and max-future-release-date-time".¶
The value corresponding to the LIMITS extension should be changed to "List of limits".¶
IANA is requested to update values corresponding to "HELP", "BURL", "FUTURERELEASE", "SMTPUTF8", "MT-PRIORITY", "RRVS", "REQUIRETLS" and "LIMITS" extensions to "MAY".¶
IANA is requested to update "Additional verbs" and "MAIL/RCPT Parameter Values" fields as per the table specified below:¶
| EHLO Keyword | Additional verbs | MAIL/RCPT Parameter Values |
|---|---|---|
| SEND | SEND | none |
| SOML | SOML | none |
| SAML | SAML | none |
| EXPN | EXPN | none |
| HELP | HELP | none |
| TURN | TURN | none |
| 8BITMIME | none | BODY parameter to MAIL command |
| SIZE | none | SIZE parameter to MAIL command |
| CHUNKING | BDAT | none |
| BINARYMIME | none | BODY parameter to MAIL command (an extra choice was added) |
| CHECKPOINT | none | TRANSID parameter to the MAIL command |
| DELIVERBY | none | BY parameter to MAIL command |
| PIPELINING | none | none |
| DSN | none | NOTIFY and ORCPT parameters to RCPT command. RET and ENVID parameters to MAIL command |
| ETRN | ETRN | none |
| ENHANCEDSTATUSCODES | none | none |
| STARTTLS | STARTTLS | none |
| NO-SOLICITING | none | SOLICIT parameter to MAIL command |
| MTRK | none | MTRK parameters to MAIL command. Also see DSN extension parameters |
| SUBMITTER | none | SUBMITTER parameters to MAIL command |
| ATRN | ATRN | none |
| AUTH | AUTH | AUTH parameter to MAIL command |
| BURL | BURL | none |
| FUTURERELEASE | none | HOLDFOR and HOLDUNTIL parameters to MAIL command. |
| UTF8SMTP | none | One optional parameter, ALT-ADDRESS, is added to the MAIL and RCPT commands |
| CONPERM | none | CONPERM parameter to MAIL command |
| CONNEG | none | CONNEG parameter to RCPT command |
| SMTPUTF8 | none | SMTPUTF8 parameter to the MAIL command |
| MT-PRIORITY | none | MT-PRIORITY parameter to MAIL command |
| RRVS | none | RRVS parameter to RCPT command |
| REQUIRETLS | none | REQUIRETLS parameter to MAIL command |
| LIMITS | none | none |
TBD: Add and/or calculate "Length Added" values.¶
This document only specifies IANA related actions, thus it doesn't directly affect security on SMTP or its extensions. However better documentation of SMTP extensions in IANA registries can, hopefully, lead to better and more secure implementations.¶