FEP-8fcf, received. When a delivery's Collection-Synchronization header digests the sender's followers on PrivaPub
otherwise than the personas following it, a job reads the list the header names (on the sender's origin, signed by the
instance actor): a follow the list leaves out ends, only when the list is the one the digest describes; a request it
lists is taken as accepted; a persona it lists that follows nothing there sends Undo{Follow}, as Mastodon does. Each
claiming delivery is compared once.
Checked live (scenarios/followsync.sh, now 15 checks): PrivaPub ends a follow Mastodon lost and undoes one only
Mastodon remembered.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01LsXgEaXee4GCU1hwYgPJXw
Owner decision of 2026-10-06 (FEP-8fcf). A persona's delivery addressed to its followers carries a signed
Collection-Synchronization header naming its followers, its roll-call (…/groupies/roll-call) and the digest of its
accepted followers on the receiving server only. The roll-call answers a signed request with the persona's followers
on the signer's server and nobody else's.
Mastodon gives every Undo{Follow} it sends after reading a roll-call the same id (…#follows//undo), so a second one
looked like a copy: an Undo of a Follow that comes again while the follow it ends exists again is now kept once per
follow.
Checked live (scenarios/followsync.sh): Mastodon drops a follow PrivaPub lost, and undoes one it lost itself.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01LsXgEaXee4GCU1hwYgPJXw
Three shapes Funkwhale 2.0 sends, each of which lost something:
- its Accept is named after the Follow it answers, on our origin (`…#follows/<uuid>/accept`), and was refused as off its
actor's origin, so no follow of a channel completed: an Accept or Reject whose id extends the id of the activity it
answers, on our origin, is now taken;
- a channel deletes its uploads in one Delete without an id, their ids in a list as the object's id: each is deleted;
- its NodeInfo discovery names the document under its swagger schema's URL: a link whose path names NodeInfo is taken
when no rel is known.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01LsXgEaXee4GCU1hwYgPJXw
Mobilizon's organiser sends the Create, Update and Delete of an event attributed to the group, which announces the
Event itself. PrivaPub refused the organiser's activities as misattributed (400) and kept the event through the
group's Announce, so an edit was lost and a deletion left the event in place. An object attributed to another account
of the actor's own server is now that server's to vouch for: created or edited as the server has it, under the account
it is attributed to, and deleted once the server answers 404 or 410. Attributed to an account elsewhere, it is still
refused. Checked against Mobilizon 5.2.4 in the pasture.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01LsXgEaXee4GCU1hwYgPJXw
Friendica's activity ids are uniqid(): a short prefix and the microsecond. Two of its processes answering two follows at
once gave both Accepts one id, and PrivaPub, queueing each inbox activity once per id, dropped the second as a copy:
that follow stayed pending on our side while Friendica counted the persona as a follower (seen in the town's Friendica
pair). An id that comes back carrying another type, actor or object is now queued apart; a true copy is still dropped.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01LsXgEaXee4GCU1hwYgPJXw
A thread's server passes on what happens in it, signed with its own key: Mastodon forwards the replies to its
accounts' posts and their deletions, Friendica every activity in its threads. PrivaPub answered them 401, which also
tells a sender its signature failed. Now they get 202 and nothing in them is believed: a forwarded Create or Update is
taken as its object reads at the actor's origin, a Delete of a public or unlisted copy once that origin answers 404 or
410 (RemoteActorService.IsGone; FederationHttp remembers the status of a refusal), anything else is let go, and our own
activities coming back are ignored. A forwarded copy has its own dedupe key, so one that failed never hides the
author's own delivery.
A reply in the thread of someone followed here is kept, as Mastodon keeps them. Mastodon delivers a reply to the
followers of the account it answers; PrivaPub dropped those as unaddressed, which the pasture showed: the outsider's
reply its Mastodon scenario said was never delivered had been, and was thrown away.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01LsXgEaXee4GCU1hwYgPJXw
WordPress's ActivityPub plugin (and Ghost and Fedify) sign with RFC 9421
first and fall back to draft-cavage only after a refusal, so each first
delivery cost two requests and a 401 in our statistics. Now a request
carrying Signature-Input is verified as an HTTP message signature: its
covered components (the method and our own public target, the body's
Content-Digest), its created and expires, with the actor's RSA key under
PKCS#1 v1.5 or PSS. Deliveries and signed fetches both take it; the
ledger names the scheme (rfc9421:rsa-v1_5-sha256). What PrivaPub sends
stays draft-cavage, which every server reads. Ed25519 waits for FEP-521a
keys.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01LsXgEaXee4GCU1hwYgPJXw
- HttpScope (AsyncLocal) tags each outbound request with a purpose and a trigger:
- purpose is set by the caller: actor, key, object, webfinger, context, nodeinfo;
- trigger is set by the job kind, by "verify" during inbox verification, or defaults
to "request".
- FederationHttp records every JSON, media and stream fetch: status, time, bytes, hops,
and an outcome of ok, refused or failed, with a reason: disallowed, remembered,
bad-redirect, too-many-redirects, content-type, too-large, bad-json, private-address,
timeout, network, or the status. A fetch a reader caused (trigger "request") is only
counted per server per day.
- Link previews record a 'preview' event: card, no-card or failed.
- The media proxy counts cache hits.
- TrafficMeter counts the client API per endpoint group, method and status class. It
counts our served documents (actor, outbox, collection, object, activity, licence,
webfinger, nodeinfo) by kind, status and whether signed, per day and never per server,
and never names a circle's collections.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01ELjqpznMFMNrJoJUj6K5p2
InboxReceiver records each answer once, in a finally, with a reason: too-large, not-json,
not-activity, missing-type-or-actor, no-signature, the signature check's own codes
(headers-unsigned, digest-mismatch, header-unreadable, date-skew, expired,
algorithm-unsupported), signature-invalid, actor-not-key-owner, key-unavailable,
id-cross-origin, undo-foreign, misattributed, unknown-recipient, and for 202s queued,
duplicate, suspended or self-delete-unknown-key. Each event carries the activity and object
type, the inbox, the signature scheme, the bytes and the time taken. A 404 for an unknown
/mouth and a rate-limited inbox (429, from OnRejected) are recorded too.
Until the signature verifies, the host is only claimed, so it is kept only if the server is
already known. A suspended server is recorded under its own name.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01ELjqpznMFMNrJoJUj6K5p2
- When a sender's key cannot be fetched because its server timed out or answered 5xx, the inbox answers 503 with
Retry-After: 300 instead of 401, so Mastodon 4.7 retries rather than switching to RFC 9421 signatures we do not
verify yet. The fetcher's failure cache now remembers whether a failure was temporary.
- Follow, Like, Block, Accept, Reject and Undo ids are deliberately not dereferenceable: serving them would publish
who follows, likes and blocks whom. They are always sent with their object embedded.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_012CzABvBkbcFqoHdmi8b9WB
- ObjectRecord, one per stored remote object: the raw JSON (up to 256 KB, always hashed), delivered or fetched,
refetched from origin or not, the activity that brought it (or caused the fetch), shared or personal inbox, the
signature's key, algorithm and signed headers, received time, published and updated, the delivering activity's
@context, and up to ten later revisions from Update.
- Delivery details travel from InboxReceiver through the inbox job to the handlers as Arrival.Current.
- A host is described from its NodeInfo when we first hear from it, at most weekly (DescribeInstance job), never when
someone opens the details view.
- GET /api/privapub/v1/statuses/:id/provenance and /api/privapub/v1/instances/:host, with the extensions an object
used detected from its raw form (044f quotes, interaction policies, contexts, proofs, Misskey fields, MFM, FEP-8967
links, emoji, polls, language maps, url variants, Markdown content).
Checked live: a GoToSocial reply shows as delivered to the shared inbox, signed hs2019 with GoToSocial's fragment-less
key id, with its interaction policy detected, and gts.test is described as gotosocial 0.22.1.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_012CzABvBkbcFqoHdmi8b9WB
DomainBlock (domain, severity, reject-media, public and private comment)
covers the domain and its subdomains. Admins manage them under
/clientapi/admin/domainblocks/{list,insert,delete}; the set is kept in
memory, reloaded on every change and at most five minutes stale.
A suspended domain is refused by FederationHttp.IsAllowed, so nothing is
fetched from it and no job delivers to it, and the inbox drops its
activities with a 202 before fetching any key. Reject-media strips the
attachments of posts from that domain. Silence is recorded for the
timelines and notifications that arrive in P1.2.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_012CzABvBkbcFqoHdmi8b9WB
InboxService is split the way the roadmap lays out Federation/Inbox:
- InboxReceiver reads and verifies the request exactly as before, runs
the checks that need no fetch (the activity id's origin, a Follow of a
missing or local-only actor, an Undo of someone else's activity, an
embedded object attributed to someone else), queues a ProcessInbox job
and answers 202. The job's dedupe key is the activity id, so a peer that
delivers the same activity twice is processed once.
- InboxProcessor (two at a time, eight attempts) loads the verified actor
and hands the activity to the handler for its type.
- Handlers/{Follow,Undo,Create,Delete,Update}Handler are the old methods,
unchanged except that they no longer produce status codes; the JSON
helpers live in Objects/ActivityJson and the group membership helpers in
Inbox/ForeignMembers.
A slow fetch of an object or a remote actor now delays the job, not the
sender's HTTP request.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_012CzABvBkbcFqoHdmi8b9WB
thepraandClaude Opus 5.5