From bbe5d3d2983a5875e919db4760f486e6f1ca496f Mon Sep 17 00:00:00 2001
From: Local Dev <dev@localhost>
Date: Thu, 22 Oct 2026 03:46:45 +0300
Subject: [PATCH] hermes: cloud-wrapped backup (opt-in B) + mobile site polish
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Users can now sign in with name + password on a device that has never seen the
account by opting into a cloud backup at account creation. The seed phrase is
locally re-wrapped with scrypt + AES-GCM keyed by the password and published
as a NIP-78 kind:30078 event under d-tag `hermes.backup.v1/<sha256(name)>`.
Relays only ever see opaque ciphertext; the password is the only decryption
key, so backup strength is password strength.

Signin tries the local wrap first (fast, no network) and falls back to the
cloud copy if the device hasn't been used before. Settings → Backup now has
"Back up to cloud" / "Re-upload" / "Remove cloud backup" controls that reuse
the Reveal-seed password field as the key.

Site: added @media breakpoints to shared.css so the header collapses cleanly
on narrow screens (icon-only brand under 380px, hidden "Sign in" label under
640px), the hero mark drops to 84px, h1 scales down, and buttons shrink to
touch sizes. Also fixed a stale reference to the removed `mnemonicBox` id in
the Create-account toggle that was throwing a TypeError on mobile.
---
 bundled-addons/hermes/addon.json |   2 +-
 bundled-addons/hermes/index.js   |   1 +
 bundled-addons/hermes/panel.html |  98 +++++++++++++++++++++++++++--
 lib/hermes.js                    |  17 ++++++
 main.js                          | 102 +++++++++++++++++++++++++++++++
 5 files changed, 213 insertions(+), 7 deletions(-)

diff --git a/bundled-addons/hermes/addon.json b/bundled-addons/hermes/addon.json
index 54ee737a..a730d9bf 100644
--- a/bundled-addons/hermes/addon.json
+++ b/bundled-addons/hermes/addon.json
@@ -1,7 +1,7 @@
 {
   "id": "hermes",
   "name": "Hermes",
-  "version": "0.2.6",
+  "version": "0.2.8",
   "description": "Message anyone by their on-chain name. End-to-end encrypted DMs over Nostr (NIP-17), identity derived from your wallet seed.",
   "author": "Silent Mode",
   "icon": "data:image/svg+xml;base64,<svg xmlns="http://www.w3.org/2000/svg" viewBox="379.94 98.42 562.35 562.35" role="img" aria-label="Hermes"><title>Hermes</title><path fill="#38BDF8" d="M547.615112,510.380951   C541.259399,500.796692 533.126343,497.300049 521.526855,496.400818   C500.401581,494.763214 483.958466,482.880280 471.383209,465.988312   C469.225677,463.090088 467.076141,462.109772 463.540192,462.189392   C441.470276,462.686310 422.286652,455.222839 406.547791,439.837952   C397.424255,430.919586 389.132050,421.150757 379.939789,411.195038   C382.865143,409.891327 384.743317,408.947113 386.696655,408.199310   C449.165222,384.284546 511.675201,360.477295 574.083008,336.405212   C584.832581,332.258850 595.279541,331.290253 606.462097,336.283142   C607.427979,323.855591 615.498108,319.253387 625.543457,315.455078   C702.431824,286.382019 779.182495,256.944824 855.991211,227.660706   C869.855164,222.374908 879.002563,226.811783 884.160767,240.893204   C901.845764,289.171265 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649.884644,332.670349   C649.901978,333.069611 649.919373,333.468903 649.936707,333.868195   C692.674133,349.266754 735.411560,364.665314 778.442444,380.169617   C793.009827,354.145325 807.305054,328.607239 821.958435,302.422882  z"/><path fill="#06111a" d="M908.947754,379.939240   C912.001160,386.873474 908.608765,393.696716 900.363647,396.849213   C838.419312,420.533539 776.458618,444.175201 714.515625,467.862976   C707.665771,470.482452 700.957275,473.479858 694.068237,475.986084   C688.051575,478.174896 685.386841,477.268372 683.045227,471.486145   C677.058716,456.702637 671.370850,441.794647 665.775635,426.857025   C657.665283,405.204895 649.739075,383.483795 641.743225,361.788818   C641.176941,360.252228 640.683533,358.688782 639.748596,355.938843   C690.025208,374.062897 739.365967,391.849609 789.064148,409.765198   C800.498169,389.734741 811.781738,369.967865 823.604675,350.074402   C825.086853,349.362274 826.363647,348.988770 826.899353,348.144867   C827.858643,346.633453 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",
diff --git a/bundled-addons/hermes/index.js b/bundled-addons/hermes/index.js
index 019c9564..9c187ad7 100644
--- a/bundled-addons/hermes/index.js
+++ b/bundled-addons/hermes/index.js
@@ -19,6 +19,7 @@ const { ipcMain } = require("electron");
 
 const PANEL_METHODS = [
   "status", "canUseVault", "close", "init", "signOut", "getBackup", "hasBackup",
+  "publishCloudBackup", "fetchCloudBackup", "hasCloudBackup", "removeCloudBackup",
   "getProfile", "updateProfile",
   "getPhone", "setPhone", "clearPhone", "findByPhones",
   "inbox", "send", "markThreadRead",
diff --git a/bundled-addons/hermes/panel.html b/bundled-addons/hermes/panel.html
index cc7d9fc1..799b350b 100644
--- a/bundled-addons/hermes/panel.html
+++ b/bundled-addons/hermes/panel.html
@@ -234,6 +234,20 @@
         <button class="primary" id="revealSeedBtn" style="background:var(--sky);color:var(--sky-ink);border:0;font:inherit;font-weight:600;padding:8px 12px;border-radius:8px;cursor:pointer;width:100%">Reveal seed phrase</button>
         <div class="err" id="backupErr" style="color:var(--err);font-size:11.5px;min-height:1em;margin-top:4px"></div>
         <div id="backupReveal" style="display:none;font-family:ui-monospace,monospace;font-size:12px;background:var(--panel-2);color:var(--ink);border:1px solid var(--line);border-radius:8px;padding:10px;margin-top:8px;line-height:1.7;word-break:break-word"></div>
+
+        <!-- Cloud backup controls — opt-in B. Visible only when a local wrap
+             exists (otherwise there's nothing to upload). The password field
+             above doubles as the key for publishing/removing the cloud copy. -->
+        <div style="margin-top:14px;padding-top:12px;border-top:1px solid var(--line)">
+          <div style="font-size:11.5px;color:var(--mut);margin-bottom:4px">Cloud backup</div>
+          <div id="cloudBackupStatus" style="font-size:11.5px;color:var(--mut);margin-bottom:6px"></div>
+          <div style="display:flex;gap:6px;flex-wrap:wrap">
+            <button id="cloudBackupBtn" style="flex:1;min-width:120px;font:inherit;font-size:12px;padding:7px 10px;background:var(--sky);color:var(--sky-ink);border:0;border-radius:6px;cursor:pointer;font-weight:600">Back up to cloud</button>
+            <button id="cloudRemoveBtn" style="flex:1;min-width:120px;font:inherit;font-size:12px;padding:7px 10px;background:transparent;color:var(--ink);border:1px solid var(--line);border-radius:6px;cursor:pointer;display:none">Remove cloud backup</button>
+          </div>
+          <div id="cloudBackupErr" style="color:var(--err);font-size:11.5px;min-height:1em;margin-top:4px"></div>
+          <div style="font-size:11px;color:var(--dim);margin-top:4px">Lets you sign in with name + password on another device. Your password is the key; relays only see opaque ciphertext.</div>
+        </div>
       </div>
     </div>
 
@@ -258,6 +272,10 @@
     <input id="createHandle" type="text" placeholder="alice" autocomplete="off" spellcheck="false" style="font-family:inherit;font-size:13px;background:var(--panel);color:var(--ink);border:1px solid var(--line);border-radius:8px;padding:9px 10px;width:100%">
     <input id="createPassword" type="password" placeholder="password (min 6)" autocomplete="new-password" style="font-family:inherit;font-size:13px;background:var(--panel);color:var(--ink);border:1px solid var(--line);border-radius:8px;padding:9px 10px;width:100%">
     <input id="createPassword2" type="password" placeholder="confirm password" autocomplete="new-password" style="font-family:inherit;font-size:13px;background:var(--panel);color:var(--ink);border:1px solid var(--line);border-radius:8px;padding:9px 10px;width:100%">
+    <label style="display:flex;align-items:flex-start;gap:8px;font-size:12px;color:var(--mut);text-align:left;cursor:pointer">
+      <input id="createCloud" type="checkbox" style="margin-top:3px;accent-color:var(--sky)">
+      <span>Back up to the cloud so I can sign in on other devices with this name + password. (You can turn this off in Settings. Your password is the only key; relays never see the seed.)</span>
+    </label>
     <button class="primary" id="useCreateBtn">Create account</button>
     <div class="hint">You'll get a handle like <code>alice.erm</code>. We'll generate a seed phrase — back it up in Settings.</div>
   </div>
@@ -276,7 +294,7 @@
   <div id="methodNamepw" class="method" style="width:100%;max-width:300px;display:flex;flex-direction:column;gap:8px">
     <input id="signinHandle" type="text" placeholder="alice" autocomplete="username" spellcheck="false" style="font-family:inherit;font-size:13px;background:var(--panel);color:var(--ink);border:1px solid var(--line);border-radius:8px;padding:9px 10px;width:100%">
     <input id="signinPassword" type="password" placeholder="password" autocomplete="current-password" style="font-family:inherit;font-size:13px;background:var(--panel);color:var(--ink);border:1px solid var(--line);border-radius:8px;padding:9px 10px;width:100%">
-    <div class="hint">Only works on this device. From a new device, use seed phrase.</div>
+    <div class="hint">Works on this device, or on any device if you turned on cloud backup. Otherwise use seed phrase.</div>
   </div>
 
   <div id="methodSeed" class="method" style="width:100%;max-width:300px;display:none;flex-direction:column;gap:8px">
@@ -705,18 +723,24 @@ async function initWithOpts(opts) {
 // ---- events ----
 $("useVaultBtn").addEventListener("click", () => initWithOpts({ useVault: true }));
 $("toggleCreateBtn").addEventListener("click", () => {
-  $("mnemonicBox").classList.remove("show");
   $("createBox").classList.toggle("show");
   if ($("createBox").classList.contains("show")) $("createHandle").focus();
 });
-$("useCreateBtn").addEventListener("click", () => {
+$("useCreateBtn").addEventListener("click", async () => {
   const handle = $("createHandle").value.trim();
   const p1 = $("createPassword").value;
   const p2 = $("createPassword2").value;
+  const wantCloud = $("createCloud").checked;
   if (!handle) { err($("signinErr"), "pick a name"); return; }
   if (p1.length < 6) { err($("signinErr"), "password must be at least 6 characters"); return; }
   if (p1 !== p2) { err($("signinErr"), "passwords don't match"); return; }
-  initWithOpts({ create: true, handle, password: p1 });
+  await initWithOpts({ create: true, handle, password: p1 });
+  if (wantCloud && state.ready) {
+    try {
+      const r = await bridge.invoke("publishCloudBackup", { password: p1 });
+      if (!r || !r.ok) console.warn("cloud backup publish failed:", r && r.err);
+    } catch (e) { console.warn("cloud backup publish threw:", e); }
+  }
 });
 
 // --- unified Sign in button + chip switcher ---
@@ -750,9 +774,21 @@ $("signinBtn").addEventListener("click", async () => {
     const btn = $("signinBtn"); const prev = btn.textContent;
     btn.disabled = true; btn.textContent = "Signing in\u2026";
     try {
+      // Try the local wrap first — fastest path, no network. If this device
+      // never saw the account, fall back to the cloud backup (opt-in B).
+      let mnemonic = null;
       const r = await bridge.invoke("getBackup", { password });
-      if (!r || !r.ok) throw new Error((r && r.err) || "wrong password or no local account");
-      const r2 = await bridge.invoke("init", { mnemonic: r.mnemonic, handle, remember: true });
+      if (r && r.ok) {
+        mnemonic = r.mnemonic;
+      } else {
+        btn.textContent = "Looking up backup…";
+        const rc = await bridge.invoke("fetchCloudBackup", { name: handle, password });
+        if (!rc || !rc.ok) {
+          throw new Error((rc && rc.err) || (r && r.err) || "wrong password or no account found");
+        }
+        mnemonic = rc.mnemonic;
+      }
+      const r2 = await bridge.invoke("init", { mnemonic, handle, remember: true });
       if (!r2 || !r2.ok) throw new Error((r2 && r2.err) || "sign-in failed");
       showApp({ pkHex: r2.pkHex, npub: r2.npub, handle: r2.handle || handle });
     } catch (e) {
@@ -887,6 +923,19 @@ async function openSettings() {
   $("backupReveal").style.display = "none";
   $("backupReveal").textContent = "";
   err($("backupErr"), "");
+
+  // Cloud backup status.
+  err($("cloudBackupErr"), "");
+  try {
+    const r = await bridge.invoke("hasCloudBackup");
+    const has = !!(r && r.ok && r.hasCloudBackup);
+    $("cloudBackupStatus").textContent = has
+      ? "Backed up to the cloud" + (r.at ? " · " + new Date(r.at).toLocaleDateString() : "")
+      : "Not backed up to the cloud";
+    $("cloudBackupStatus").style.color = has ? "var(--ok,#4fd1a5)" : "var(--mut)";
+    $("cloudBackupBtn").textContent = has ? "Re-upload backup" : "Back up to cloud";
+    $("cloudRemoveBtn").style.display = has ? "inline-block" : "none";
+  } catch {}
   $("settingsModal").classList.add("show");
 }
 
@@ -972,6 +1021,43 @@ $("revealSeedBtn").addEventListener("click", async () => {
   } finally { $("revealSeedBtn").disabled = false; }
 });
 
+$("cloudBackupBtn").addEventListener("click", async () => {
+  const password = $("backupPassword").value;
+  err($("cloudBackupErr"), "");
+  if (!password) { err($("cloudBackupErr"), "enter your password above"); return; }
+  const btn = $("cloudBackupBtn"); const prev = btn.textContent;
+  btn.disabled = true; btn.textContent = "Uploading…";
+  try {
+    const r = await bridge.invoke("publishCloudBackup", { password });
+    if (!r || !r.ok) throw new Error((r && r.err) || "upload failed");
+    $("cloudBackupStatus").textContent = "Backed up to the cloud (" + r.accepted + "/" + r.total + " relays)";
+    $("cloudBackupStatus").style.color = "var(--ok,#4fd1a5)";
+    $("cloudRemoveBtn").style.display = "inline-block";
+    btn.textContent = "Re-upload backup";
+  } catch (e) {
+    err($("cloudBackupErr"), (e && e.message) || String(e));
+    btn.textContent = prev;
+  } finally { btn.disabled = false; }
+});
+
+$("cloudRemoveBtn").addEventListener("click", async () => {
+  err($("cloudBackupErr"), "");
+  if (!confirm("Remove the cloud backup for this account? You'll no longer be able to sign in with name + password on a new device.")) return;
+  const btn = $("cloudRemoveBtn"); const prev = btn.textContent;
+  btn.disabled = true; btn.textContent = "Removing…";
+  try {
+    const r = await bridge.invoke("removeCloudBackup");
+    if (!r || !r.ok) throw new Error((r && r.err) || "remove failed");
+    $("cloudBackupStatus").textContent = "Not backed up to the cloud";
+    $("cloudBackupStatus").style.color = "var(--mut)";
+    $("cloudBackupBtn").textContent = "Back up to cloud";
+    btn.style.display = "none";
+  } catch (e) {
+    err($("cloudBackupErr"), (e && e.message) || String(e));
+    btn.textContent = prev;
+  } finally { btn.disabled = false; }
+});
+
 $("search").addEventListener("input", renderContacts);
 $("backBtn").addEventListener("click", () => {
   state.selected = null;
diff --git a/lib/hermes.js b/lib/hermes.js
index a0b5e848..70f44531 100644
--- a/lib/hermes.js
+++ b/lib/hermes.js
@@ -321,6 +321,23 @@ export async function buildPhoneClaimEvent({ sk, phone } = {}) {
 }
 
 /** Deletion event (NIP-09, kind:5) that retracts earlier claim events by id. */
+// NIP-78 kind:30078 parameterised replaceable event carrying a
+// password-wrapped mnemonic. d-tag = `hermes.backup.v1/<16-byte hex of
+// sha256(bareName)>` so a client can locate it from name + password alone.
+// Content stays opaque to relays — only AES-GCM + scrypt protect the seed.
+export const BACKUP_DTAG_PREFIX = "hermes.backup.v1/";
+
+export function buildBackupEvent({ sk, dtag, content } = {}) {
+  if (!sk) throw new Error("sk required");
+  if (!dtag) throw new Error("dtag required");
+  return finalizeEvent({
+    kind: 30078,
+    tags: [["d", dtag]],
+    content: typeof content === "string" ? content : JSON.stringify(content || {}),
+    created_at: Math.floor(Date.now() / 1000),
+  }, sk);
+}
+
 export function buildPhoneRetractEvent({ sk, eventIds } = {}) {
   if (!sk || !Array.isArray(eventIds) || !eventIds.length) throw new Error("sk + eventIds required");
   return finalizeEvent({
diff --git a/main.js b/main.js
index 31df4e27..4509be23 100644
--- a/main.js
+++ b/main.js
@@ -10784,6 +10784,108 @@ global._hermesAPI = {
   },
   hasBackup: () => hOk({ hasBackup: !!hermesLoadWrappedMnemonic() }),
 
+  // ---- cloud backup (opt-in B) ---------------------------------------------
+  // Publishes the password-wrapped mnemonic as a NIP-78 kind:30078 event
+  // keyed by d-tag = "hermes.backup.v1/<sha256(bareName)>". On a new device
+  // the user enters the same name + password; the client queries relays for
+  // the event, decrypts the wrap, and signs in without ever typing the seed
+  // phrase. Each ciphertext is encrypted with scrypt + aes-256-gcm (same
+  // params as hermesWrapMnemonic) so the password strength IS the backup
+  // strength — relays store opaque bytes.
+  publishCloudBackup: async ({ password } = {}) => {
+    if (!hermesState) return hErr("not initialised");
+    if (!password) return hErr("password required");
+    if (!hermesState.handle) return hErr("this account has no handle set — cloud backup needs one");
+    const localWrap = hermesLoadWrappedMnemonic();
+    if (!localWrap) return hErr("no local wrap to publish — only accounts created with a password can be backed up this way");
+    let mnemonic;
+    try { mnemonic = hermesUnwrapMnemonic(localWrap, password); }
+    catch { return hErr("wrong password — doesn't match the one you set at signup"); }
+    try {
+      const H = await loadHermesLib();
+      const sk = Uint8Array.from(Buffer.from(hermesState.skHex, "hex"));
+      const wrap = hermesWrapMnemonic(mnemonic, password);
+      const bareName = hermesState.handle.toLowerCase().split(".")[0];
+      const nameHash = nodeCrypto.createHash("sha256").update(bareName, "utf8").digest("hex").slice(0, 32);
+      const dtag = H.BACKUP_DTAG_PREFIX + nameHash;
+      const signed = H.buildBackupEvent({
+        sk,
+        dtag,
+        content: { v: 1, handle: hermesState.handle, wrap },
+      });
+      const results = await hermesPublishEvent(signed, HERMES_DEFAULT_RELAYS);
+      const accepted = results.filter((r) => r.ok).length;
+      if (!accepted) return hErr("no relay accepted the backup — try again or add more relays");
+      hermesUpdateIdentityMeta({
+        cloudBackupAt: new Date().toISOString(),
+        cloudBackupEventId: signed.id,
+      });
+      return hOk({ accepted, total: results.length });
+    } catch (e) { return hErr(e); }
+  },
+
+  hasCloudBackup: () => {
+    const meta = hermesLoadIdentityMeta();
+    return hOk({ hasCloudBackup: !!(meta && meta.cloudBackupAt), at: meta && meta.cloudBackupAt || null });
+  },
+
+  removeCloudBackup: async () => {
+    if (!hermesState) return hErr("not initialised");
+    const meta = hermesLoadIdentityMeta();
+    const evId = meta && meta.cloudBackupEventId;
+    if (!evId) {
+      hermesUpdateIdentityMeta({ cloudBackupAt: null, cloudBackupEventId: null });
+      return hOk({ deleted: false, note: "no tracked backup event; cleared local marker" });
+    }
+    try {
+      const H = await loadHermesLib();
+      const sk = Uint8Array.from(Buffer.from(hermesState.skHex, "hex"));
+      const retract = H.buildPhoneRetractEvent({ sk, eventIds: [evId] });
+      await hermesPublishEvent(retract, HERMES_DEFAULT_RELAYS);
+      hermesUpdateIdentityMeta({ cloudBackupAt: null, cloudBackupEventId: null });
+      return hOk({ deleted: true });
+    } catch (e) { return hErr(e); }
+  },
+
+  // Fetch + decrypt cloud backup for sign-in on a new device.
+  // Does NOT touch hermesState — the client calls init() with the returned
+  // mnemonic to actually sign in.
+  fetchCloudBackup: async ({ name, password } = {}) => {
+    if (!name || !password) return hErr("name and password required");
+    try {
+      const bareName = String(name).toLowerCase().split(".")[0].replace(/^hermes:/, "");
+      const nameHash = nodeCrypto.createHash("sha256").update(bareName, "utf8").digest("hex").slice(0, 32);
+      const dtag = "hermes.backup.v1/" + nameHash;
+      const found = await new Promise((resolve) => {
+        let best = null;
+        let pending = HERMES_DEFAULT_RELAYS.length;
+        const finish = () => resolve(best);
+        for (const url of HERMES_DEFAULT_RELAYS) {
+          const ws = new WebSocket(url);
+          const close = () => { try { ws.close(1000); } catch {}; if (--pending <= 0) finish(); };
+          const t = setTimeout(close, 5000);
+          ws.on("open", () => ws.send(JSON.stringify(["REQ", "b-" + Math.random().toString(36).slice(2, 8),
+            { kinds: [30078], "#d": [dtag], limit: 1 }])));
+          ws.on("message", (buf) => {
+            let msg; try { msg = JSON.parse(buf.toString()); } catch { return; }
+            if (msg[0] === "EVENT" && msg[2] && msg[2].kind === 30078) {
+              if (!best || msg[2].created_at > best.created_at) best = msg[2];
+            } else if (msg[0] === "EOSE") { clearTimeout(t); close(); }
+          });
+          ws.on("error", () => { clearTimeout(t); close(); });
+        }
+      });
+      if (!found) return hErr("no cloud backup found for \"" + name + "\"");
+      let payload;
+      try { payload = JSON.parse(found.content); } catch { return hErr("corrupt backup payload"); }
+      if (!payload || payload.v !== 1 || !payload.wrap) return hErr("unsupported backup version");
+      try {
+        const mnemonic = hermesUnwrapMnemonic(payload.wrap, password);
+        return hOk({ mnemonic, handle: payload.handle || null });
+      } catch { return hErr("wrong password"); }
+    } catch (e) { return hErr(e); }
+  },
+
   // ---- phone discovery (opt-in) --------------------------------------------
   // Publishes a kind:30078 claim event bound to a hash of the phone number,
   // signed by the user's Hermes key. The phone number itself is normalised