eleven / messenger Public

home: enrolment reuses the tab's live session — no re-ceremony after create (#1378) (#1382)

Co-authored-by: Claude Fable 5 <noreply@anthropic.com>

Paul Campbell 2 months ago d2c4092728cc9a1614afc4357f55d8a331cf4c7f parent 97d318a

5 files changed, +101 −3

changelog/2026-07-28-enrol-session-reuse.md +5 −0
home/test/sessionreuse.test.mjs +35 −0
home/web/static/enroll.js +43 −2
home/web/static/sessionreuse.js +17 −0
package.json +1 −1

diff --git a/changelog/2026-07-28-enrol-session-reuse.md b/changelog/2026-07-28-enrol-session-reuse.md

new file mode 100644

index 0000000..d7bd6a4

--- /dev/null

+++ b/changelog/2026-07-28-enrol-session-reuse.md

@@ -0,0 +1,5 @@

+🤖 Create a space from your Eleven account and, when Eleven asks you to sign

+in during setup, one tap now finishes it — no second Face ID for the account

+you're already signed into, and no wrong turn toward accidentally creating a

+second one. Everything still checks out against your account first; if the

+sign-in isn't live any more, the usual ceremony runs exactly as before.

diff --git a/home/test/sessionreuse.test.mjs b/home/test/sessionreuse.test.mjs

new file mode 100644

index 0000000..569ba61

--- /dev/null

+++ b/home/test/sessionreuse.test.mjs

@@ -0,0 +1,35 @@

+// Tests for the enrolment live-session fast-path decision (#1378), run in

+// Node. Same harness style as home/test/serverlist.test.mjs.

+// node home/test/sessionreuse.test.mjs

+import assert from "node:assert/strict";

+import { reuseCandidate } from "../web/static/sessionreuse.js";

+const store = (entries) => ({ getItem: (k) => (k in entries ? entries[k] : null) });

+let pass = 0;

+function test(name, fn) {

+ fn();

+ pass++;

+ console.log("PASS ", name);

+test("both halves present → candidate with token + dek", () => {

+ assert.deepEqual(

+ reuseCandidate(store({ home_token: "tok", home_dek: "dek64" })),

+ { token: "tok", dek: "dek64" },

+ );

+});

+test("either half missing → null (ceremony path)", () => {

+ assert.equal(reuseCandidate(store({ home_token: "tok" })), null, "no DEK — a persisted token alone never skips the ceremony");

+ assert.equal(reuseCandidate(store({ home_dek: "dek64" })), null, "no token");

+ assert.equal(reuseCandidate(store({})), null, "cold tab");

+ assert.equal(reuseCandidate(store({ home_token: "", home_dek: "" })), null, "empty strings are absent");

+});

+test("throwing or absent storage → null, never a crash", () => {

+ assert.equal(reuseCandidate({ getItem: () => { throw new Error("denied"); } }), null);

+ assert.equal(reuseCandidate(null), null);

+});

+console.log("\nALL PASSED (" + pass + ")");

diff --git a/home/web/static/enroll.js b/home/web/static/enroll.js

index c502b32..675d999 100644

--- a/home/web/static/enroll.js

+++ b/home/web/static/enroll.js

@@ -14,10 +14,11 @@

// below — the user sees what's being added before anything is written.

import {

- b64urlToBytes, kekFromPRF, generateDEK, wrapDEK, unwrapDEK,

+ b64urlToBytes, kekFromPRF, generateDEK, importDEK, wrapDEK, unwrapDEK,

sealBlob, unpackBlob, openBlob,

} from "/static/crypto.js";

import { beginRegister, beginLogin, runRegister, runLogin, fetchBlob, putBlob } from "/static/backup-core.js";

+import { reuseCandidate } from "/static/sessionreuse.js";

import { formatCeremonyError } from "/static/ceremony-errors.js";

import { clearTombstone } from "/static/serverlist.js";

@@ -122,6 +123,15 @@ function prefetch() {

// up-front "I'm new" button (createAndAdd) runs the register path directly.

async function saveSecurely() {

disable();

+ // The live-session fast path (#1378): the create→setup→enrol journey is

+ // same-tab by design, so the tab that just created this space usually still

+ // holds a live session — the link token plus the tab-scoped DEK

+ // (home.js § session state). Both were minted by a full ceremony in this

+ // very tab, and both are validated against the server below, so reusing

+ // them grants nothing a fresh assertion wouldn't — it just spares the user

+ // a Face ID for an account this tab is already signed into, and closes the

+ // second-account trapdoor a dismissed assertion opened (offerCreate).

+ if (await trySessionReuse()) return;

setStatus("Looking for your sign-in…", "busy");

let login;

try {

@@ -136,6 +146,30 @@ async function saveSecurely() {

await addWithLogin(login);

}

+// trySessionReuse: false = no usable live session, run the ceremony. True =

+// the save was handled end-to-end (or genuinely failed — those errors

+// propagate to onError like the ceremony path's). Every soft failure —

+// missing halves, a dead token, a stale DEK that can't open the blob — falls

+// back to the ceremony rather than guessing.

+async function trySessionReuse() {

+ let cand = null;

+ try { cand = reuseCandidate(sessionStorage); } catch { return false; }

+ if (!cand) return false;

+ let got, dek, opened;

+ try {

+ setStatus("Checking your sign-in…", "busy");

+ got = await fetchBlob(cand.token); // throws on a dead token (401)

+ if (!got) return false; // signed in but no backup yet — the ceremony path knows that case

+ dek = await importDEK(cand.dek);

+ opened = await openBlob(got.bytes, dek);

+ } catch {

+ setStatus("", "");

+ return false;

+ }

+ await applyEntry({ token: cand.token, dek, got, opened });

+ return true;

// createBlobFor writes a fresh backup whose only server is this entry, keyed to

// the given credential. Shared by "create a new passkey" and the "signed in but

// no backup yet" case, so both start a backup rather than fragmenting.

@@ -194,7 +228,14 @@ async function addWithLogin({ token, credId, prf }) {

return;

}

const dek = await unwrapDEK(wrapped, kek);

+ await applyEntry({ token, dek, got, opened: await openBlob(got.bytes, dek) });

+// applyEntry merges the payload entry into an unlocked blob and saves it —

+// the shared tail of the ceremony path (addWithLogin) and the live-session

+// fast path (trySessionReuse). Ends in succeed(), a terminal keep-what-I-have

+// message, or a thrown error for onError.

+async function applyEntry({ token, dek, got, opened }) {

// If an entry with DIFFERENT credentials already exists for this host, adding

// would overwrite the credentials the user already trusts. Anyone can open

// this page with an arbitrary fragment, so a page that knows the host could

@@ -204,7 +245,7 @@ async function addWithLogin({ token, credId, prf }) {

// and an existing entry with NO credentials — the address-only stub the

// create-a-space flow saves. There's nothing to clobber; enrolment upgrades

// the stub with this space's key (and its real name).

- let cur = got, opened = await openBlob(got.bytes, dek);

+ let cur = got;

const existing = (opened.obj.servers || []).find((s) => s.url === payload.entry.url);

if (existing && existing.credentials && credFingerprint(existing) !== credFingerprint(payload.entry)) {

const ok = await confirmReplace(existing);

diff --git a/home/web/static/sessionreuse.js b/home/web/static/sessionreuse.js

new file mode 100644

index 0000000..5303c3f

--- /dev/null

+++ b/home/web/static/sessionreuse.js

@@ -0,0 +1,17 @@

+// The enrolment live-session fast path's DECISION, pure and dependency-free

+// so it's unit-testable in Node (#1378; the harness style of serverlist.js).

+// A candidate exists only when both halves of a live home session are present

+// in the given store — the link token AND the tab-scoped DEK (home.js

+// § session state; the DEK never outlives the tab by design). The caller

+// (enroll.js trySessionReuse) still validates both against the server — fetch

+// the blob, unseal it — before trusting them; this only decides whether

+// there's anything to try instead of a fresh passkey ceremony.

+export function reuseCandidate(store) {

+ try {

+ const token = (store && store.getItem("home_token")) || "";

+ const dek = (store && store.getItem("home_dek")) || "";

+ return token && dek ? { token, dek } : null;

+ } catch {

+ return null; // storage unavailable (private mode) — ceremony it is

+ }

diff --git a/package.json b/package.json

index 1934512..4aaaa19 100644

--- a/package.json

+++ b/package.json

@@ -3,6 +3,6 @@

"private": true,

"type": "module",

"scripts": {

- "test": "node --test test/module-refs.test.mjs && node test/apps-dir.test.mjs && node test/crypto.test.mjs && node test/vaultcrypto.test.mjs && node test/integrity.test.mjs && node test/ui.test.mjs && node test/blurhash.test.mjs && node test/format.test.mjs && node test/markdown.test.mjs && node test/composer.test.mjs && node test/composer-vectors.test.mjs && node test/bootscene.test.mjs && node test/message.test.mjs && node test/threadkey.test.mjs && node test/nicknames.test.mjs && node test/messageblob.test.mjs && node test/blobbytes.test.mjs && node test/nativeblob.test.mjs && node test/apps.test.mjs && node test/appcatalog.test.mjs && node test/appcatalog-seed.test.mjs && node test/cards.test.mjs && node test/event-vectors.test.mjs && node test/views.test.mjs && node test/schema-engine.test.mjs && node test/flow.test.mjs && node test/quickform.test.mjs && node test/tutorial.test.mjs && node test/actions.test.mjs && node test/commands.test.mjs && node test/context.test.mjs && node test/knowledge.test.mjs && node test/invite.test.mjs && node test/backup.test.mjs && node test/connect.test.mjs && node test/serviceop.test.mjs && node test/github.test.mjs && node test/github-render.test.mjs && node test/linear.test.mjs && node test/linear-render.test.mjs && node test/check-app.test.mjs && node test/sandbox.test.mjs && node test/sandbox-bridge.test.mjs && node test/sandbox-theme.test.mjs && node test/status-contract.test.mjs && node test/ledgerchain.test.mjs && node test/hardening-posture.test.mjs && node test/store.test.mjs && node test/memory.test.mjs && node test/search.test.mjs && node test/stripe-band-prices.test.mjs && node test/waterfall.test.mjs && node home/test/crypto.test.mjs && node home/test/restore-payload.test.mjs && node home/test/serverlist.test.mjs && node home/test/ceremony-errors.test.mjs && node home/test/fader.test.mjs && node home/test/fx.test.mjs"

+ "test": "node --test test/module-refs.test.mjs && node test/apps-dir.test.mjs && node test/crypto.test.mjs && node test/vaultcrypto.test.mjs && node test/integrity.test.mjs && node test/ui.test.mjs && node test/blurhash.test.mjs && node test/format.test.mjs && node test/markdown.test.mjs && node test/composer.test.mjs && node test/composer-vectors.test.mjs && node test/bootscene.test.mjs && node test/message.test.mjs && node test/threadkey.test.mjs && node test/nicknames.test.mjs && node test/messageblob.test.mjs && node test/blobbytes.test.mjs && node test/nativeblob.test.mjs && node test/apps.test.mjs && node test/appcatalog.test.mjs && node test/appcatalog-seed.test.mjs && node test/cards.test.mjs && node test/event-vectors.test.mjs && node test/views.test.mjs && node test/schema-engine.test.mjs && node test/flow.test.mjs && node test/quickform.test.mjs && node test/tutorial.test.mjs && node test/actions.test.mjs && node test/commands.test.mjs && node test/context.test.mjs && node test/knowledge.test.mjs && node test/invite.test.mjs && node test/backup.test.mjs && node test/connect.test.mjs && node test/serviceop.test.mjs && node test/github.test.mjs && node test/github-render.test.mjs && node test/linear.test.mjs && node test/linear-render.test.mjs && node test/check-app.test.mjs && node test/sandbox.test.mjs && node test/sandbox-bridge.test.mjs && node test/sandbox-theme.test.mjs && node test/status-contract.test.mjs && node test/ledgerchain.test.mjs && node test/hardening-posture.test.mjs && node test/store.test.mjs && node test/memory.test.mjs && node test/search.test.mjs && node test/stripe-band-prices.test.mjs && node test/waterfall.test.mjs && node home/test/crypto.test.mjs && node home/test/restore-payload.test.mjs && node home/test/serverlist.test.mjs && node home/test/ceremony-errors.test.mjs && node home/test/fader.test.mjs && node home/test/fx.test.mjs && node home/test/sessionreuse.test.mjs"

}