mirror of
https://codeberg.org/fediverse/fep.git
synced 2026-08-05 19:55:46 +00:00
FEP-ef61: Media integrity protection (#450)
- Added new section, "Media". - Added digestMultibase to FEP context. - Updated "History" section. - Removed context.jsonld file. Reviewed-on: https://codeberg.org/fediverse/fep/pulls/450 Co-authored-by: silverpill <silverpill@firemail.cc> Co-committed-by: silverpill <silverpill@firemail.cc>
This commit is contained in:
silverpill
silverpill
@@ -1,9 +0,0 @@
|
||||
{
|
||||
"@context": {
|
||||
"gateways": {
|
||||
"@id": "https://w3id.org/fep/ef61/gateways",
|
||||
"@type": "http://www.w3.org/2001/XMLSchema#anyURI",
|
||||
"@container": "@list"
|
||||
}
|
||||
}
|
||||
}
|
||||
@@ -4,6 +4,7 @@
|
||||
"@id": "https://w3id.org/fep/ef61/gateways",
|
||||
"@type": "http://www.w3.org/2001/XMLSchema#anyURI",
|
||||
"@container": "@list"
|
||||
}
|
||||
},
|
||||
"digestMultibase": "https://www.w3.org/ns/credentials/v2#digestMultibase"
|
||||
}
|
||||
}
|
||||
|
||||
+34
-14
@@ -26,9 +26,9 @@ The proposed solution should satisfy the following constraints:
|
||||
|
||||
## History
|
||||
|
||||
[Streams](https://codeberg.org/streams/streams) implemented [Nomadic Identity](https://codeberg.org/streams/streams/src/commit/5a20e0102b73a2c05e72bead13ddd712e4c2f885/FEDERATION.md#nomadic-identity) mechanism, that makes identity independent from a server. Nomadic accounts were not supported by ActivityPub but were available via the [Nomad protocol](https://codeberg.org/streams/streams/src/commit/11f5174fdd3dfcd8714974f93d8b8fc50378a193/spec/Nomad/Home.md).
|
||||
[Streams](https://codeberg.org/streams/streams) implemented [Nomadic Identity](https://codeberg.org/streams/streams/src/commit/5a20e0102b73a2c05e72bead13ddd712e4c2f885/FEDERATION.md#nomadic-identity) mechanism, that makes identity independent from a server. Nomadic accounts were not supported by ActivityPub at the time, but were available via the [Nomad protocol](https://codeberg.org/streams/streams/src/commit/11f5174fdd3dfcd8714974f93d8b8fc50378a193/spec/Nomad/Home.md).
|
||||
|
||||
[Decentralized Identifiers (DIDs) v1.0][DID] specification suggests that DIDs might be assigned to web resources in section [B.8 Assigning DIDs to existing web resources](https://www.w3.org/TR/did-core/#assigning-dids-to-existing-web-resources).
|
||||
[FEP-c390](https://codeberg.org/fediverse/fep/src/branch/main/fep/c390/fep-c390.md) (2022) introduced a decentralized identity solution compatible with ActivityPub. It enabled permissionless migration of followers between servers, but didn't provide full data portability.
|
||||
|
||||
## Requirements
|
||||
|
||||
@@ -171,7 +171,8 @@ Example:
|
||||
{
|
||||
"@context": [
|
||||
"https://www.w3.org/ns/activitystreams",
|
||||
"https://w3id.org/security/data-integrity/v1"
|
||||
"https://w3id.org/security/data-integrity/v1",
|
||||
"https://w3id.org/fep/ef61"
|
||||
],
|
||||
"type": "Note",
|
||||
"id": "ap://did:key:z6MkrJVnaZkeFzdQyMZu1cgjg7k1pZZ6pvBQ7XJPt4swbTQ2/objects/dc505858-08ec-4a80-81dd-e6670fd8c55f",
|
||||
@@ -181,7 +182,7 @@ Example:
|
||||
"attachment": [
|
||||
{
|
||||
"type": "Image",
|
||||
"href": "ap://did:key:z6MkrJVnaZkeFzdQyMZu1cgjg7k1pZZ6pvBQ7XJPt4swbTQ2/media/image123.png",
|
||||
"url": "hl:zQmdfTbBqBPQ7VNxZEYEj14VmRuZBkqFbiwReogJgS1zR1n",
|
||||
"mediaType": "image/png",
|
||||
"digestMultibase": "zQmdfTbBqBPQ7VNxZEYEj14VmRuZBkqFbiwReogJgS1zR1n"
|
||||
}
|
||||
@@ -218,6 +219,33 @@ And the origin of a [DID URL][DID-URL] MUST be computed by the following algorit
|
||||
3. Let `uri-port` be the number 0.
|
||||
4. Return the triple `(uri-scheme, uri-host, uri-port)`.
|
||||
|
||||
## Media
|
||||
|
||||
Integrity of an external resource is attested with a digest. When a portable object contains a reference to an external resource (such as image), it MUST also contain a [`digestMultibase`](https://w3c.github.io/vc-data-integrity/#resource-integrity) property representing the integrity digest of that resource. The digest MUST be computed using the SHA-256 algorithm.
|
||||
|
||||
The URI of an external resource SHOULD be a [hashlink][Hashlinks].
|
||||
|
||||
Example of an `Image` attachment:
|
||||
|
||||
```json
|
||||
{
|
||||
"type": "Image",
|
||||
"url": "hl:zQmdfTbBqBPQ7VNxZEYEj14VmRuZBkqFbiwReogJgS1zR1n",
|
||||
"mediaType": "image/png",
|
||||
"digestMultibase": "zQmdfTbBqBPQ7VNxZEYEj14VmRuZBkqFbiwReogJgS1zR1n"
|
||||
}
|
||||
```
|
||||
|
||||
After retrieving a resource, the client MUST verify its integrity by computing its digest and comparing the result with the value encoded in `digestMultibase` property.
|
||||
|
||||
Resources attached to portable objects using hashlinks can be stored by gateways. To retrieve a resource from a gateway, the client MUST make an HTTP GET request to the gateway endpoint at [well-known] location `/.well-known/apgateway`. The value of a hashlink URI MUST be appended to the gateway base URL.
|
||||
|
||||
Example of a request:
|
||||
|
||||
```
|
||||
GET https://social.example/.well-known/apgateway/hl:zQmdfTbBqBPQ7VNxZEYEj14VmRuZBkqFbiwReogJgS1zR1n
|
||||
```
|
||||
|
||||
## Compatibility
|
||||
|
||||
### Identifiers
|
||||
@@ -260,16 +288,6 @@ This proposal makes use of the `gateways` property, but the following alternativ
|
||||
|
||||
Also, `gateways` array can contain HTTP(S) URL with a path component, thus enabling discovery based on ["follow your nose"](https://indieweb.org/follow_your_nose) principle, as opposed to discovery based on a [well-known] location.
|
||||
|
||||
### Media
|
||||
|
||||
Integrity of external resources can be attested using the [`digestMultibase`](https://w3c.github.io/vc-data-integrity/#resource-integrity) property.
|
||||
|
||||
Gateways can be used to store resources attached to portable objects. Consuming implementations can retrieve these resources by their content hashes:
|
||||
|
||||
```
|
||||
https://social.example/.well-known/apgateway/urn:sha256:11a8c27212f7bbc47a952494581f3bc92e84883ac343cd11a1e4f8eaa1254f4b
|
||||
```
|
||||
|
||||
### Compatibility
|
||||
|
||||
The following alternatives to gateway-based compatible IDs are being considered:
|
||||
@@ -295,6 +313,7 @@ The following alternatives to gateway-based compatible IDs are being considered:
|
||||
- silverpill, [FEP-ae97: Client-side activity signing][FEP-ae97], 2023
|
||||
- silverpill, [FEP-fe34: Origin-based security model][FEP-fe34], 2024
|
||||
- A. Barth, [The Web Origin Concept][RFC-6454], 2011
|
||||
- M. Sporny, L. Rosenthol, [Cryptographic Hyperlinks][Hashlinks], 2021
|
||||
- silverpill, [FEP-521a: Representing actor's public keys][FEP-521a], 2023
|
||||
- a, Evan Prodromou, [ActivityPub and WebFinger][WebFinger], 2024
|
||||
- Dave Longley, Manu Sporny, [Verifiable Credential Data Integrity 1.0][Data Integrity], 2024
|
||||
@@ -313,6 +332,7 @@ The following alternatives to gateway-based compatible IDs are being considered:
|
||||
[FEP-ae97]: https://codeberg.org/fediverse/fep/src/branch/main/fep/ae97/fep-ae97.md
|
||||
[FEP-fe34]: https://codeberg.org/fediverse/fep/src/branch/main/fep/fe34/fep-fe34.md
|
||||
[RFC-6454]: https://www.rfc-editor.org/rfc/rfc6454.html
|
||||
[Hashlinks]: https://datatracker.ietf.org/doc/html/draft-sporny-hashlink-07
|
||||
[FEP-521a]: https://codeberg.org/fediverse/fep/src/branch/main/fep/521a/fep-521a.md
|
||||
[WebFinger]: https://swicg.github.io/activitypub-webfinger/
|
||||
[Data Integrity]: https://w3c.github.io/vc-data-integrity/
|
||||
|
||||
Reference in New Issue
Block a user