JMAP Blob management extension
draft-ietf-jmap-blob-08
The information below is for an old version of the document.
| Document | Type | Active Internet-Draft (jmap WG) | |
|---|---|---|---|
| Author | Bron Gondwana | ||
| Last updated | 2021-12-20 (Latest revision 2021-11-22) | ||
| Replaces | draft-gondwana-jmap-blob | ||
| Stream | Internet Engineering Task Force (IETF) | ||
| Formats | plain text html xml htmlized pdfized bibtex | ||
| Stream | WG state | Waiting for WG Chair Go-Ahead | |
| Associated WG milestone |
|
||
| Document shepherd | Jim Fenton | ||
| IESG | IESG state | I-D Exists | |
| Consensus boilerplate | Unknown | ||
| Telechat date | (None) | ||
| Responsible AD | (None) | ||
| Send notices to | fenton@bluepopcorn.net |
draft-ietf-jmap-blob-08
JMAP B. Gondwana, Ed.
Internet-Draft Fastmail
Updates: 8620 (if approved) 20 December 2021
Intended status: Standards Track
Expires: 23 June 2022
JMAP Blob management extension
draft-ietf-jmap-blob-08
Abstract
The JMAP base protocol (RFC8620) provides the ability to upload and
download arbitrary binary data via HTTP POST and GET on defined
endpoint. This binary data is called a "blob".
This extension adds additional ways to create and access blobs, by
making inline method calls within a standard JMAP request.
This extension also adds a reverse lookup mechanism to discover where
blobs are referenced within other data types.
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 23 June 2022.
Copyright Notice
Copyright (c) 2021 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
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and restrictions with respect to this document. Code Components
extracted from this document must include Revised BSD License text as
described in Section 4.e of the Trust Legal Provisions and are
provided without warranty as described in the Revised BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Conventions Used In This Document . . . . . . . . . . . . . . 3
3. Addition to the Capabilities Object . . . . . . . . . . . . . 3
3.1. urn:ietf:params:jmap:blob . . . . . . . . . . . . . . . . 3
3.1.1. Capability Example . . . . . . . . . . . . . . . . . 4
4. Blob Methods . . . . . . . . . . . . . . . . . . . . . . . . 5
4.1. Blob/set . . . . . . . . . . . . . . . . . . . . . . . . 5
4.1.1. create . . . . . . . . . . . . . . . . . . . . . . . 5
4.1.2. update . . . . . . . . . . . . . . . . . . . . . . . 7
4.1.3. destroy . . . . . . . . . . . . . . . . . . . . . . . 7
4.1.4. Blob/set simple example . . . . . . . . . . . . . . . 7
4.1.5. Blob/set complex example with catenate . . . . . . . 8
4.2. Blob/get . . . . . . . . . . . . . . . . . . . . . . . . 11
4.2.1. Blob/get simple example . . . . . . . . . . . . . . . 12
4.2.2. Blob/get example with range and encoding errors . . . 13
4.3. Blob/lookup . . . . . . . . . . . . . . . . . . . . . . . 19
4.3.1. Blob/lookup example . . . . . . . . . . . . . . . . . 20
5. Security considerations . . . . . . . . . . . . . . . . . . . 22
6. IANA considerations . . . . . . . . . . . . . . . . . . . . . 22
6.1. JMAP Capability registration for "blob" . . . . . . . . . 22
6.2. JMAP Error Codes Registration for "unknownDataType" . . . 23
6.3. Creation of "JMAP Data Types" Registry . . . . . . . . . 23
7. Changes . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 27
9. Normative References . . . . . . . . . . . . . . . . . . . . 27
10. Informative References . . . . . . . . . . . . . . . . . . . 27
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 27
1. Introduction
Sometimes JMAP ([RFC8620]) interactions require creating a blob and
then referencing it. In the same way that IMAP Literals ([RFC7888])
were extended to reduce roundtrips for simple data, embedding simple
small blobs into the JMAP method stream can reduce roundtrips.
Likewise, when fetching an object, it can be useful to also fetch the
raw content of that object without a separate roundtrip.
Since raw blobs could contain arbitrary binary data, this document
allows the use of the base64 coding specified in [RFC4648].
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Where JMAP is being proxied through a system which applies additional
access restrictions, it can be useful to know where a blob is
referenced in order to decide whether to allow it to be downloaded,
so this document defines a way to look up where a particular blobId
is referenced.
2. Conventions Used In This Document
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.
3. Addition to the Capabilities Object
The capabilities object is returned as part of the JMAP Session
object; see [RFC8620], Section 2.
This document defines an additional capability URI.
3.1. urn:ietf:params:jmap:blob
The capability urn:ietf:params:jmap:blob being present in the
"accountCapabilities" property of an account represents support for
additional API methods on the Blob datatype. Servers that include
the capability in one or more "accountCapabilities" properties MUST
also include the property in the "capabilities" property.
The value of this property in the JMAP session "capabilities"
property MUST be an empty object.
The value of this property in an account's "accountCapabilities"
property is an object that MAY contain the following information on
server capabilities and permissions for that account:
* maxSizeBlobSet: UnsignedInt|null
if set, gives the maximum size of a blob in octets that the server
will allow to be created (size of the final output of catenate or
of encoded forms).
Clients MUST NOT attempt to create blobs larger than this size.
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If this value is not set, clients MUST NOT attempt to create blobs
larger than the value of maxSizeUpload specified in [RFC8620]. If
neither of those limits are specified by the server, then clients
are not required to limit the size of blob they try to create,
though servers can always reject creation of blobs regardless of
size, e.g. due to lack of disk space or per-user rate limits.
* maxCatenateItems: UnsignedInt|null
if set, gives the maximum number of of CatenateSourceObjects
allowed per creation in a Blob/set. Servers MUST allow at least
64 items.
If not set, clients SHOULD assume a limit of 64 items.
* supportedTypeNames: [String]|null
an array of data type names that are supported for Blob/lookup.
May be null or not present if the account does not support reverse
lookups.
3.1.1. Capability Example
{
"capabilities": {
...,
"urn:ietf:params:jmap:blob": {}
},
"accounts": {
"A13842": {
...
"accountCapabilities": {
"urn:ietf:params:jmap:blob": {
"maxSizeBlobSet": 50000000,
"maxCatenateItems": 100,
"supportedTypeNames" : [
"Mailbox",
"Thread",
"Email"
]
}
}
}
}
}
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4. Blob Methods
A blob is a sequence of zero or more octets.
The JMAP base spec [RFC8620] defines the Blob/copy method, which is
unchanged by this specfication, and is selected by the
urn:ietf:params:jmap:core capability.
The following JMAP Methods are selected by the
urn:ietf:params:jmap:blob capability.
4.1. Blob/set
This is a standard JMAP set method.
4.1.1. create
*Properties:*
Exactly one of:
* data:asText: String
data which can be represented as utf-8 encoded text
* data:asBase64: String
binary data encoded as a ([RFC4648] Section 4) Base 64 string
* catenate: [CatenateSourceObject]
list of one or more octet sources in order
Also optionally:
* type: String|null (default: null)
hint for media type of the data
Result is:
* id: Id
the blobId which was created
* type: String|null
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the media type as given in the creation (if any); or detected from
content; or null
* size: UnsignedInt
as per RFC8620 - the size of the created blob in octets
Plus any other properties identical to those that would be returned
in the JSON response of the RFC8620 upload endpoint (which may be
extended in the future - this document anticipates that
implementations will extend both the upload endpoint and the Blob/set
responses in the same way)
CatenateSourceObject:
Exactly one of:
* data:asText: String|null
* data:asBase64: String|null
or a blobId source:
* blobId: Id
* offset: UnsignedInt|null (MAY be zero)
* length: UnsignedInt|null (MUST NOT be zero)
If null then offset is assumed to be zero.
If null then length is the remaining octets in the blob.
If the range can not be fully satisfied (i.e. extends past the end of
the data in the blob) then the catenate itself is invalid and results
in a notCreated response for this creation id.
If the data properties or catenate properties have any invalid
references or invalid data contained in them, the server MUST NOT
guess as to the user's intent, and MUST reject the creation and
return a notCreated response for that creation id.
Likewise, invalid characters in the base64 of data:asBase64, or
invalid UTF-8 in data:asText MUST result in a nonCreated response.
It is legal to create a blob by calling catenate with a single
CatenateSourceObject. Please note that a catenate source MUST NOT
contain additional sub-catenates, only data or blob sources.
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It is envisaged that catenate sources might be extended in future,
for example to fetch external content.
A server SHOULD accept at least 64 catenate items.
4.1.2. update
It is not possible to update a Blob, so any update will result in a
notUpdated response.
4.1.3. destroy
It is not possible to destroy a Blob, so any destroy will result in a
notDestroyed response.
4.1.4. Blob/set simple example
The data:asBase64 field is set over multiple lines for ease of
publication here, however all data:asBase64 would be sent as a
continuous string with no whitespace on the wire.
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Method Call:
[
"Blob/set",
{
"accountId": "account1",
"create": {
"1": {
"data:asBase64": "iVBORw0KGgoAAAANSUhEUgAAAAEAAAABAQMAAAAl21bKA
AAAA1BMVEX/AAAZ4gk3AAAAAXRSTlN/gFy0ywAAAApJRE
FUeJxjYgAAAAYAAzY3fKgAAAAASUVORK5CYII=",
"type": "image/png"
},
},
},
"R1"
]
Response:
[
"Blob/set",
{
"accountId" : "account1",
"created" : {
"1": {
"id" : "G4c6751edf9dd6903ff54b792e432fba781271beb",
"type" : "image/png",
"size" : 95
},
},
},
"R1"
]
4.1.5. Blob/set complex example with catenate
Method Calls:
[
[
"Blob/set",
{
"create": {
"b4": {
"data:asText": "The quick brown fox jumped over the lazy dog."
}
}
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},
"S4"
],
[
"Blob/set",
{
"create": {
"cat": {
"catenate": [
{
"data:asText": "How"
},
{
"blobId": "#b4",
"length": 7,
"offset": 3
},
{
"data:asText": "was t"
},
{
"blobId": "#b4",
"length": 1,
"offset": 1
},
{
"data:asBase64": "YXQ/"
}
]
}
}
},
"CAT"
],
[
"Blob/get",
{
"properties": [
"data:asText",
"size"
],
"ids": [
"#cat"
]
},
"G4"
]
]
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Responses:
[
[
"Blob/set",
{
"oldState": null,
"created": {
"b4": {
"id": "Gc0854fb9fb03c41cce3802cb0d220529e6eef94e",
"size": 45,
"type": "application/octet-stream"
}
},
"updated": null,
"destroyed": null,
"notCreated": null,
"notUpdated": null,
"notDestroyed": null,
"accountId": "account1"
},
"S4"
],
[
"Blob/set",
{
"oldState": null,
"created": {
"cat": {
"id": "Gcc60576f036321ae6e8037ffc56bdee589bd3e23",
"size": 19,
"type": "application/octet-stream"
}
},
"updated": null,
"destroyed": null,
"notCreated": null,
"notUpdated": null,
"notDestroyed": null,
"accountId": "account1"
},
"CAT"
],
[
"Blob/get",
{
"list": [
{
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"id": "Gcc60576f036321ae6e8037ffc56bdee589bd3e23",
"data:asText": "How quick was that?",
"size": 19
}
],
"notFound": [],
"accountId": "account1"
},
"G4"
]
]
4.2. Blob/get
A standard JMAP get, with two additional optional parameters:
* offset: UnsignedInt|null
start this many octets into the blob data. If null or
unspecified, this defaults to zero.
* length: UnsignedInt|null
return at most this many octets of the blob data. If null or
unspecified, then all remaining octets in the blob are returned.
This can be considered equivalent to an infinitely large length
value, except that the isTruncated warning is not given unless the
start offset is past the end of the blob.
*Request Properties:*
Any of
* data:asText
* data:asBase64
* data (returns data:asText if the selected octets are valid UTF-8,
or data:asBase64)
* size
If not given, properties defaults to data and size.
*Result Properties:*
* data:asText: String|null
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the raw octets of the selected range if they are valid UTF-8,
otherwise null
* data:asBase64: String
the base64 encoding of the octets in the selected range
* isEncodingProblem: Boolean (default: false)
* isTruncated: Boolean (default: false)
* size: UnsignedInt
the number of octets in the entire blob
The size value MUST always be the number of octets in the underlying
blob, regardless of offset and length.
The data fields contain a representation of the octets within the
selected range that are present in the blob. If the octets selected
are not valid UTF-8 (including truncating in the middle of a multi-
octet sequence) and data or data:asText was requested, then the key
isEncodingProblem MUST be set to true and the data:asText response
value MUST be null. In the case where data was requested and the
data is not valid UTF-8, then data:asBase64 MUST be returned.
If the selected range requests data outside the blob (i.e. the
offset+length is larger than the blob) then the result is either just
the octets from the offset to the end of the blob, or an empty string
if the offset is past the end of the blob. Either way, the
isTruncated property in the result MUST be set to true to tell the
client that the requested range could not be fully satisfied.
4.2.1. Blob/get simple example
Where a blob containing the string "The quick brown fox jumped over
the lazy dog!" has blobId G6ec94756e3e046be78fcb33953b85b944e70673e.
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Method Call:
[
"Blob/get",
{
"accountId" : "account1",
"ids" : [
"G6ec94756e3e046be78fcb33953b85b944e70673e",
"not-a-blob"
],
"properties" : [
"data:asText",
"data:asBase64",
"size"
],
"offset" : 4,
"length" : 9
},
"R1"
]
Response:
[
"Blob/get",
{
"accountId": "account1",
"list": [
{
"id": "G6ec94756e3e046be78fcb33953b85b944e70673e",
"data:asText": "quick bro",
"data:asBase64": "cXVpY2sgYnJvCg==",
"size": 46
}
],
"notFound": [
"not-a-blob"
]
},
"R1"
]
4.2.2. Blob/get example with range and encoding errors
The b1 value is the text: "The quick brown fox jumped over the
\x81\x81 fox" which contains an invalid utf8 sequence.
The results have the following interesting properties:
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* G1: defaults to data and size - so b1 returns isEncodingProblem
and a base64 value.
* G2: since data:asText was explicitly selected, does not attempt to
return a value for the data, just isEncodingProblem for b1.
* G3: since only data:asBase64 was requested, there is no encoding
problem and both values are returned.
* G4: since the requested range could be satisfied as text, both
blobs are returned as data:asText and there is no encoding
problem.
* G5: both blobs cannot satisfy the requested range, so isTruncated
is true for both.
Note: some values have been wrapped for line length - there would be
no whitespace in the data:asBase64 values on the wire
Method calls:
[
[
"Blob/set",
{
"create": {
"b1": {
"data:asBase64": "VGhlIHF1aWNrIGJyb3duIGZveCBqdW1wZW
Qgb3ZlciB0aGUggYEgZG9nLg=="
},
"b2": {
"data:asText": "hello world",
"type" : "text/plain"
}
}
},
"S1"
],
[
"Blob/get",
{
"ids": [
"#b1",
"#b2"
]
},
"G1"
],
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[
"Blob/get",
{
"ids": [
"#b1",
"#b2"
],
"properties": [
"data:asText",
"size"
]
},
"G2"
],
[
"Blob/get",
{
"ids": [
"#b1",
"#b2"
],
"properties": [
"data:asBase64",
"size"
]
},
"G3"
],
[
"Blob/get",
{
"offset": 0,
"length": 5,
"ids": [
"#b1",
"#b2"
]
},
"G4"
],
[
"Blob/get",
{
"offset": 20,
"length": 100,
"ids": [
"#b1",
"#b2"
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]
},
"G5"
]
]
Responses:
[
[
"Blob/set",
{
"oldState": null,
"created": {
"b2": {
"id": "G2aae6c35c94fcfb415dbe95f408b9ce91ee846ed",
"size": 11,
"type": "application/octet-stream"
},
"b1": {
"id": "G72cfa4804194563685d9a4b695f7ba20e7739576",
"size": 43,
"type": "text/plain"
}
},
"updated": null,
"destroyed": null,
"notCreated": null,
"notUpdated": null,
"notDestroyed": null,
"accountId": "account1"
},
"S1"
],
[
"Blob/get",
{
"list": [
{
"id": "G72cfa4804194563685d9a4b695f7ba20e7739576",
"isEncodingProblem": true,
"data:asBase64": "VGhlIHF1aWNrIGJyb3duIGZveCBqdW1wZW
Qgb3ZlciB0aGUggYEgZG9nLg==",
"size": 43
},
{
"id": "G2aae6c35c94fcfb415dbe95f408b9ce91ee846ed",
"data:asText": "hello world",
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"size": 11
}
],
"notFound": [],
"accountId": "account1"
},
"G1"
],
[
"Blob/get",
{
"list": [
{
"id": "G72cfa4804194563685d9a4b695f7ba20e7739576",
"isEncodingProblem": true,
"size": 43
},
{
"id": "G2aae6c35c94fcfb415dbe95f408b9ce91ee846ed",
"data:asText": "hello world",
"size": 11
}
],
"notFound": [],
"accountId": "account1"
},
"G2"
],
[
"Blob/get",
{
"list": [
{
"id": "G72cfa4804194563685d9a4b695f7ba20e7739576",
"data:asBase64": "VGhlIHF1aWNrIGJyb3duIGZveCBqdW1wZW
Qgb3ZlciB0aGUggYEgZG9nLg==",
"size": 43
},
{
"id": "G2aae6c35c94fcfb415dbe95f408b9ce91ee846ed",
"data:asBase64": "aGVsbG8gd29ybGQ=",
"size": 11
}
],
"notFound": [],
"accountId": "account1"
},
"G3"
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],
[
"Blob/get",
{
"list": [
{
"id": "G72cfa4804194563685d9a4b695f7ba20e7739576",
"data:asText": "The q",
"size": 43
},
{
"id": "G2aae6c35c94fcfb415dbe95f408b9ce91ee846ed",
"data:asText": "hello",
"size": 11
}
],
"notFound": [],
"accountId": "account1"
},
"G4"
],
[
"Blob/get",
{
"list": [
{
"id": "G72cfa4804194563685d9a4b695f7ba20e7739576",
"isTruncated": true,
"isEncodingProblem": true,
"data:asBase64": "anVtcGVkIG92ZXIgdGhlIIGBIGRvZy4=",
"size": 43
},
{
"id": "G2aae6c35c94fcfb415dbe95f408b9ce91ee846ed",
"isTruncated": true,
"data:asText": "",
"size": 11
}
],
"notFound": [],
"accountId": "account1"
},
"G5"
]
]
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4.3. Blob/lookup
Given a list of blobIds, this method does a reverse lookup in each of
the provided type names to find the list of Ids within that data type
which reference the provided blob.
The definition of reference is somewhat loosely defined, but roughly
means "you could discover this blobId by looking inside this object",
for example if a Mailbox contains an Email which references the
blobId, then it references that blobId. Likewise for a Thread.
*Parameters*
* accountId: Id
The id of the account used for the call.
* typeNames: [String]
A list of names from the "JMAP Data Types" registry. Only names
for which "Can reference blobs" is true may be specified, and the
capability which defines each type must also be used by the
overall JMAP request in which this method is called.
If a type name is not known by the server, or the associated
capability has not been requested, then the server returns an
"unknownDataType" error.
* ids: [Id]
A list of blobId values to be looked for.
*Response*
* list: [BlobInfo]
A list of BlobInfo objects.
*BlobInfo Object*
* id: Id
The Blob Identifier.
* matchedIds: String[Id List]
A map from type name to list of Ids of that data type (e.g. the
name "Email" maps to a list of emailIds)
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If a blob is not visible to a user at all, then the server SHOULD
return that blobId in the notFound array, however it may also return
an empty list for each type name, as it may not be able to know if
other data types do reference that blob.
4.3.1. Blob/lookup example
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Method call:
[
"Blob/lookup",
{
"typeNames": [
"Mailbox",
"Thread",
"Email"
],
"ids": [
"Gd2f81008cf07d2425418f7f02a3ca63a8bc82003",
"not-a-blob"
]
},
"R1"
]
Response:
[
"Blob/lookup",
{
"list": [
{
"id": "Gd2f81008cf07d2425418f7f02a3ca63a8bc82003",
"matchedIds": {
"Mailbox": [
"M54e97373",
"Mcbe6b662"
],
"Thread": [
"T1530616e"
],
"Email": [
"E16e70a73eb4",
"E84b0930cf16"
]
}
}
],
"notFound": [
"not-a-blob"
]
},
"R1"
]
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5. Security considerations
JSON parsers are not all consistent in handling non-UTF-8 data. JMAP
requires that all JSON data be UTF-8 encoded, so servers MUST only
return a null value if data:asText is requested for a range of octets
which is not valid UTF-8, and set isEncodingProblem: true.
Servers MUST apply any access controls, such that if the
authenticated user would be unable to discover the blobId by making
queries, then this fact can't be discovered via a Blob/lookup. For
example, if an Email exists in a Mailbox which the authenticated user
does not have access to see, then that emailId MUST not be returned
in a lookup for a blob which is referenced by that email.
If a server might sometimes return all names empty rather than
putting a blobId in the notFound response to a Blob/get, then the
server SHOULD always return the same type of response, regardless of
whether a blob exists but the user can't access it, or doesn't exist
at all. This avoids leaking information about the existence of the
blob.
The server MUST NOT trust that the data given to a Blob/set is a well
formed instance of the specified media type, and if the server
attempts to parse the given blob, only hardened parsers designed to
deal with arbitrary untrusted data should be used. The server SHOULD
NOT reject data on the grounds that it is not a valid specimen of the
stated type.
Blob/set catenate can be used to recreate dangerous content on the
far side of security scanners (anti-virus or exfiltration scanners
for example) which may be watching the upload endpoint. Server
implementations SHOULD provide a hook to allow security scanners to
check the resulting blobId from a catenate in the same way that they
do for the upload endpoint.
6. IANA considerations
6.1. JMAP Capability registration for "blob"
IANA is requested to register the "blob" JMAP Capability as follows:
Capability Name: urn:ietf:params:jmap:blob
Specification document: this document
Intended use: common
Change Controller: IETF
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Security and privacy considerations: this document, Section XXX
6.2. JMAP Error Codes Registration for "unknownDataType"
IANA is requested to register the "unknownDataType" JMAP Error Code
as follows:
JMAP Error Code: unknownDataType
Intended use: common
Change Controller: IETF
Reference: this document
Description: The server does not recognise this data type, or the
capability to enable it was not present.
6.3. Creation of "JMAP Data Types" Registry
IANA is requested to create a new registry "JMAP Data Types" with the
initial content:
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+================+=========+======+=====================================+=========+
|Type Name |Can |Can |Capability |Reference|
| |reference|use | | |
| |blobs |for | | |
| | |state | | |
| | |change| | |
+================+=========+======+=====================================+=========+
|Core |No |No |urn:ietf:params:jmap:core |[RFC8620]|
+----------------+---------+------+-------------------------------------+---------+
|PushSubscription|No |No |urn:ietf:params:jmap:core |[RFC8620]|
+----------------+---------+------+-------------------------------------+---------+
|Mailbox |Yes |Yes |urn:ietf:params:jmap:mail |[RFC8621]|
+----------------+---------+------+-------------------------------------+---------+
|Thread |Yes |Yes |urn:ietf:params:jmap:mail |[RFC8621]|
+----------------+---------+------+-------------------------------------+---------+
|Email |Yes |Yes |urn:ietf:params:jmap:mail |[RFC8621]|
+----------------+---------+------+-------------------------------------+---------+
|EmailDelivery |No |Yes |urn:ietf:params:jmap:mail |[RFC8621]|
+----------------+---------+------+-------------------------------------+---------+
|SearchSnippet |No |No |urn:ietf:params:jmap:mail |[RFC8621]|
+----------------+---------+------+-------------------------------------+---------+
|Identity |No |Yes |urn:ietf:params:jmap:submission |[RFC8621]|
+----------------+---------+------+-------------------------------------+---------+
|EmailSubmission |No |Yes |urn:ietf:params:jmap:submission |[RFC8621]|
+----------------+---------+------+-------------------------------------+---------+
|VacationResponse|No |Yes |urn:ietf:params:jmap:vacationresponse|[RFC8621]|
+----------------+---------+------+-------------------------------------+---------+
|MDN |No |No |urn:ietf:params:jmap:mdn |[RFC9007]|
+----------------+---------+------+-------------------------------------+---------+
Table 1
7. Changes
EDITOR: please remove this section before publication.
The source of this document exists on github at:
https://github.com/brong/draft-gondwana-jmap-blob/
(https://github.com/brong/draft-gondwana-jmap-blob/)
*draft-ietf-jmap-blob-08*:
* Fixed spelling of Neil's name in acknowledgements
* Last call review (thanks Jim Fenton)
- fixed mmark sillyness causing RFC8620 to be non-normative in
the references
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- clarified the capability object and accountCapability object
requirements
- made capability keys much more tightly defined, with mandatory
minimum catenate limit and default values.
- increased use of normative language generally
- lowercased 'blob' anywhere it wasn't explicitly the object
- lowercased titles of the columns in the registry
*draft-ietf-jmap-blob-07*:
* more examples to cover the interactions of offset, length and
encoding checks.
*draft-ietf-jmap-blob-06*:
* removed asHex - we only need base64 and text
* added reference to where base64 is defined
* made 'destroy' not be allowed
* expanded JSON examples for readability
* removed 'expires' from examples
*draft-ietf-jmap-blob-05*:
* discovered I hadn't actually included typeNames and matchedIds
anywhere except the updates section, oops!
* added a catenate example
* tightened up some text
*draft-ieft-jmap-blob-04*:
* added security considerations for scanning catenate results
*draft-ieft-jmap-blob-03*:
* added capabilities object
* renamed types to typeNames and matchedIds
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* added details of how to handle non-UTF8 data and truncation in
Blob/get
* added isTruncated and isEncodingProblem to Blob/get to tell the
client if the request wasn't entirely satisfied.
*draft-ieft-jmap-blob-02*:
* fixed incorrect RFC number in reference and HTTP PUT -> POST,
thanks Ken.
* added acknowledgements section
* removed all 'datatype' text and changed to 'data type' or 'type
name' as appropriate (issue #1 proposal)
* expanded security considerations section and moved optional Blob/
lookup empty case into Blob/lookup section
*draft-ieft-jmap-blob-01*:
* renamed 'datatypes' to 'types' to align with PushSubscription from
RFC8620.
* added example for Blob/get
* specified offset and length precisely
*draft-ieft-jmap-blob-00*:
* initial adoption as an IETF document, otherwise identical to
draft-gondwana-jmap-blob-02
*draft-gondwana-jmap-blob-02*
* renamed 'objects' to 'datatypes'
* specified Blob/lookup
* added IANA registry for datatypes
*draft-gondwana-jmap-blob-01*
* added an example
*draft-gondwana-jmap-blob-00*
* initial proposal
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8. Acknowledgements
Joris Baum, Jim Fenton, Neil Jenkins, Alexey Melnikov, Ken Murchison,
Robert Stepanek and the JMAP working group at the IETF.
9. Normative References
[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>.
[RFC4648] Josefsson, S., "The Base16, Base32, and Base64 Data
Encodings", RFC 4648, DOI 10.17487/RFC4648, October 2006,
<https://www.rfc-editor.org/info/rfc4648>.
[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>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
10. Informative References
[RFC7888] Melnikov, A., Ed., "IMAP4 Non-synchronizing Literals",
RFC 7888, DOI 10.17487/RFC7888, May 2016,
<https://www.rfc-editor.org/info/rfc7888>.
[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
Bron Gondwana (editor)
Fastmail
Level 2, 114 William St
Melbourne VIC 3000
Australia
Email: brong@fastmailteam.com
URI: https://www.fastmail.com
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