S/MIME signature verification extension to JMAP
draft-ietf-jmap-smime-01
The information below is for an old version of the document.
| Document | Type | Active Internet-Draft (jmap WG) | |
|---|---|---|---|
| Author | Alexey Melnikov | ||
| Last updated | 2020-02-10 | ||
| Stream | Internet Engineering Task Force (IETF) | ||
| Formats | plain text xml htmlized pdfized bibtex | ||
| Reviews |
GENART Telechat review
(of
-09)
Ready with Nits
ARTART Last Call review
(of
-08)
Ready with Issues
OPSDIR Last Call review
(of
-07)
Has Nits
GENART Last Call review
(of
-07)
Ready with Issues
|
||
| Stream | WG state | WG Document | |
| Associated WG milestone |
|
||
| Document shepherd | (None) | ||
| IESG | IESG state | I-D Exists | |
| Consensus boilerplate | Yes | ||
| Telechat date | (None) | ||
| Responsible AD | (None) | ||
| Send notices to | (None) |
draft-ietf-jmap-smime-01
Network Working Group A. Melnikov
Internet-Draft Isode Ltd
Intended status: Informational February 10, 2020
Expires: August 13, 2020
S/MIME signature verification extension to JMAP
draft-ietf-jmap-smime-01
Abstract
This document specifies an extension to JMAP for returning S/MIME
signature verification status.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on August 13, 2020.
Copyright Notice
Copyright (c) 2020 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(https://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Melnikov Expires August 13, 2020 [Page 1]
Internet-Draft JMAP extension for S/MIME February 2020
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Conventions Used in This Document . . . . . . . . . . . . . . 2
3. Addition to the capabilities object . . . . . . . . . . . . . 2
4. Extension to Email/get for S/MIME signature verification . . 2
5. Open Issues . . . . . . . . . . . . . . . . . . . . . . . . . 5
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 5
6.1. JMAP capability registration for "smime" . . . . . . . . 5
7. Security Considerations . . . . . . . . . . . . . . . . . . . 6
8. Normative References . . . . . . . . . . . . . . . . . . . . 6
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 6
1. Introduction
[RFC8621] is a JSON based application protocol for synchronising
email data between a client and a server.
This document describes an extension to JMAP for returning S/MIME
[RFC8551] signature verification status, without requiring a JMAP
client to download the signature body part and all signed body parts
(when multipart/signed media type is used) or to download and decode
CMS (when application/pkcs7-mime media type is used).
2. Conventions Used in This Document
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119].
3. Addition to the capabilities object
The capabilities object is returned as part of the standard JMAP
Session object; see the JMAP spec. Servers supporting _this_
specification MUST add a property called "urn:ietf:params:jmap:smime"
to the capabilities object.
The value of this property is an empty object in both the JMAP
session _capabilities_ property and an account's
_accountCapabilities_ property.
4. Extension to Email/get for S/MIME signature verification
[RFC8621] defines Email/get method for retrieving message specific
information. This document defines the following pseudo values in
the _properties_ argument:
Melnikov Expires August 13, 2020 [Page 2]
Internet-Draft JMAP extension for S/MIME February 2020
o *smimeStatus*: If "smimeStatus" is included in the list of
requested properties, it MUST be interpreted by the server as a
request to return "smimeStatus" response property.
o *smimeErrors*: If "smimeErrors" is included in the list of
requested properties, it MUST be interpreted by the server as a
request to return "smimeErrors" response property.
The "smimeStatus" response property is defined as follows:
smimeStatus: "String|null". null signifies that the message doesn't
contain any signature. This property contains the S/MIME signature
and certificate verification status calculated according to [RFC8551]
and [RFC8550]. Possible string values of the property are listed
below. Servers MAY return other values not defined below. Client
MUST treat unrecognized values as "unknown" or "signed/failed". Note
that the value of this property might change over time.
unknown S/MIME message, but it is neither signed, nor encrypted.
This can also be returned for a multipart/signed message which
contains unrecognized signing protocol (for example OpenPGP).
signed S/MIME signed message, but the signature was not yet
verified. Some servers might not attempt to verify signature
until a particular message is requested by the client. JMAP
servers compliant with this document SHOULD return "signed/
verified" or "signed/failed" instead of this signature status.
signed/verified S/MIME signed message and the sender's signature was
successfully verified, sender matches the From header field and
the sender's certificate (and the certificate chain) is trusted
for signing.
signed/failed S/MIME signed message, but the signature failed to
verify. This might be a policy related decision (message signer
doesn't match the From header field), message was modified, the
signer's certificate has expired or was revoked, etc.
The "smimeErrors" response property is defined as follows:
smimeErrors: "String[]|null". null signifies that the message doesn't
contain any signature or that there were no errors when verifying
S/MIME signature. (I.e. this property is non null only when the
corresponding "smimeStatus" response property value is "signed/
failed".) Each string in the array is a human readable description
of a problem with the signature or the signing certificate. For
example, the signing certificate might be expired and the message
From email address might not correspond to any of the email addresses
in the signing certificate. Or the certificate might be expired and
Melnikov Expires August 13, 2020 [Page 3]
Internet-Draft JMAP extension for S/MIME February 2020
the JMAP server might be unable to retrieve CRL for the certificate.
In both of these cases there would be 2 elements in the array.
"smimeStatus" and "smimeErrors" values are calculated at the time the
corresponding JMAP request was processed, not at the time when the
message was generated (according to it's Date header field value).
It MAY be calculated at the time the message was delivered to the
mailbox. As recalculating these values is expensive for the server
they MAY be cached for up to 10 minutes from the moment when they
were calculated.
["Email/get", {
"ids": [ "f123u987" ],
"properties": [ "mailboxIds", "from", "subject", "date",
"smimeStatus" ]
}, "#1"]
This will result in the following response:
[["Email/get", {
"accountId": "abc",
"state": "41234123231",
"list": [
{
id: "f123u457",
mailboxIds: { "f123": true },
from: [{name: "Joe Bloggs", email: "joe@bloggs.example.net"}],
subject: "Dinner on Thursday?",
date: "2013-10-13T14:12:00Z",
smimeStatus: "signed/verified"
}
]
}, "#1"]]
Example 1:
Melnikov Expires August 13, 2020 [Page 4]
Internet-Draft JMAP extension for S/MIME February 2020
["Email/get", {
"ids": [ "af123u123" ],
"properties": [ "mailboxIds", "from", "subject", "date",
"smimeStatus", "smimeErrors" ]
}, "#1"]
This will result in the following response:
[["Email/get", {
"accountId": "abc",
"state": "41234123231",
"list": [
{
id: "af123u123",
mailboxIds: { "f123": true },
from: [{name: "Jane Doe", email: "jdoe@example.com"}],
subject: "Company takeover",
date: "2020-01-31T23:00:00Z",
smimeStatus: "signed/failed",
smimeErrors: ["From email address doesn't match the certificate",
"Can't retrieve CRL from the CRL URL"]
}
]
}, "#1"]]
Example 2:
5. Open Issues
[[This section should be empty before publication]]
1. Should the date/time of [the last] verification be returned as a
response property?
6. IANA Considerations
6.1. JMAP capability registration for "smime"
IANA is requested to register the "smime" JMAP Capability as follows:
Capability Name: "urn:ietf:params:jmap:smime"
Specification document: this document
Intended use: common
Change Controller: IETF
Melnikov Expires August 13, 2020 [Page 5]
Internet-Draft JMAP extension for S/MIME February 2020
Security and privacy considerations: this document, Section 7
7. Security Considerations
Server side S/MIME signature verification requires the client to
trust server verification code and configuration to perform S/MIME
signature verification. For example, if the server is not configured
with some Trust Anchors, some messages will have "signed/failed"
status instead of "signed/verified".
TBD.
8. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC8550] Schaad, J., Ramsdell, B., and S. Turner, "Secure/
Multipurpose Internet Mail Extensions (S/MIME) Version 4.0
Certificate Handling", RFC 8550, DOI 10.17487/RFC8550,
April 2019, <https://www.rfc-editor.org/info/rfc8550>.
[RFC8551] Schaad, J., Ramsdell, B., and S. Turner, "Secure/
Multipurpose Internet Mail Extensions (S/MIME) Version 4.0
Message Specification", RFC 8551, DOI 10.17487/RFC8551,
April 2019, <https://www.rfc-editor.org/info/rfc8551>.
[RFC8620] Jenkins, N. and C. Newman, "The JSON Meta Application
Protocol (JMAP)", RFC 8620, DOI 10.17487/RFC8620, July
2019, <https://www.rfc-editor.org/info/rfc8620>.
[RFC8621] Jenkins, N. and C. Newman, "The JSON Meta Application
Protocol (JMAP) for Mail", RFC 8621, DOI 10.17487/RFC8621,
August 2019, <https://www.rfc-editor.org/info/rfc8621>.
Author's Address
Alexey Melnikov
Isode Ltd
14 Castle Mews
Hampton, Middlesex TW12 2NP
UK
EMail: Alexey.Melnikov@isode.com
Melnikov Expires August 13, 2020 [Page 6]