Files
dchain/client-app/app/(app)/devices.tsx
vsecoder af7223b93c feat(client): device pairing flow (v2.2.0-alpha3)
Completes PR #3 of the multi-device roadmap. Two devices of the same
identity can now be linked via a six-digit code + relay envelope
handshake. Chain-level fan-out (alpha2) and self-wipe on revoke (this
release, earlier commit) already work end-to-end.

New device — app/(auth)/pair.tsx:
  * Generates fresh X25519 keypair + six-digit code locally.
  * Displays them for transcription on the primary device.
  * Polls /relay/inbox on its own x25519 pub every 2.5s.
  * Decrypts each envelope with the session priv + sender_pub.
  * Accepts only payloads where {v=1, type=pair-handshake, code matches}.
  * On success, assembles a KeyFile (master Ed25519 from envelope,
    x25519 from session) and redirects into (app).

Primary device — app/(app)/devices.tsx:
  * "Link new device" opens a modal asking for {code, device key, name}.
  * On submit: builds+submits LINK_DEVICE tx for the new pub, then
    sends a one-shot relay envelope carrying {master_pub, master_priv,
    master_x25519_pub, code} encrypted for the new device's x25519 pub.
  * Optimistic local insert so the new row appears immediately.

Entry point — app/index.tsx:
  * Third button on welcome slide 3: "Pair". Routes to /auth/pair.
    Create / Import remain unchanged for fresh identities.

Security:
  * Master Ed25519 priv leaves the source device ONLY inside an envelope
    sealed with NaCl box for the new device's X25519 pub. The relay node
    sees only ciphertext.
  * Six-digit code (~20 bits) gates acceptance — an attacker who guesses
    both a session pub AND the code is still filtered by the X25519
    decryption itself (code match is belt-and-suspenders).
  * Envelope stays in relay mailbox until TTL — no DELETE call yet;
    idempotent on our side (saveKeyFile overwrites, session pub
    never polled after redirect).

Known trade-offs:
  * Manual transcription of a 64-char hex key is ugly. Alpha4 will
    offer a QR fallback on phones with cameras; desktop keeps typing.
  * No rate limit on the polling. Fine for a 1-minute handshake, needs
    cap-on-stale if a user leaves the screen open.
2026-04-22 16:32:34 +03:00

491 lines
18 KiB
TypeScript

/**
* Devices screen — Settings → Linked devices.
*
* Multi-device registry (v2.2.0). Lists every X25519 device published
* on-chain under this identity's master Ed25519 key. Operators can:
* - see added-at timestamps
* - rename this device (local alias for now; rename via LINK_DEVICE
* with same pub + new name is a v2.3 polish)
* - revoke a remote device via UNLINK_DEVICE (requires fee)
* - pair a new device (Phase 3 — separate modal, stub for now)
*
* This device is NEVER listed with an Unlink button — revoking yourself
* is a footgun (you'd wipe your own state on next launch). Export/import
* your key first, then revoke from the new device.
*/
import React, { useCallback, useEffect, useState } from 'react';
import {
View, Text, ScrollView, Pressable, ActivityIndicator, Alert, RefreshControl,
TextInput, KeyboardAvoidingView, Platform, Modal,
} from 'react-native';
import { Ionicons } from '@expo/vector-icons';
import { useSafeAreaInsets } from 'react-native-safe-area-context';
import { useStore } from '@/lib/store';
import {
fetchDevices, buildLinkDeviceTx, buildUnlinkDeviceTx, submitTx,
sendEnvelope, humanizeTxError,
type DeviceInfo,
} from '@/lib/api';
import { encryptMessage } from '@/lib/crypto';
import { Header } from '@/components/Header';
import { IconButton } from '@/components/IconButton';
import { safeBack } from '@/lib/utils';
function shortPub(p: string, n = 8): string {
if (!p) return '—';
return p.length <= n * 2 + 1 ? p : `${p.slice(0, n)}${p.slice(-n)}`;
}
function formatDate(unixSec: number): string {
return new Date(unixSec * 1000).toLocaleString();
}
export default function DevicesScreen() {
const insets = useSafeAreaInsets();
const keyFile = useStore(s => s.keyFile);
const [devices, setDevices] = useState<DeviceInfo[]>([]);
const [loading, setLoading] = useState(true);
const [refreshing, setRefreshing] = useState(false);
const [unlinking, setUnlinking] = useState<string | null>(null); // pub being revoked
const load = useCallback(async (isRefresh = false) => {
if (!keyFile) return;
if (isRefresh) setRefreshing(true);
else setLoading(true);
try {
const list = await fetchDevices(keyFile.pub_key);
setDevices(list);
} finally {
setLoading(false);
setRefreshing(false);
}
}, [keyFile]);
useEffect(() => { load(false); }, [load]);
const onUnlink = useCallback((dev: DeviceInfo) => {
if (!keyFile) return;
Alert.alert(
'Unlink device?',
`"${dev.device_name}" will stop receiving messages sent to you. ` +
`This costs a small network fee. The revoked device wipes its ` +
`local state the next time it checks in.`,
[
{ text: 'Cancel', style: 'cancel' },
{
text: 'Unlink',
style: 'destructive',
onPress: async () => {
setUnlinking(dev.x25519_pub_key);
try {
const tx = buildUnlinkDeviceTx({
from: keyFile.pub_key,
x25519Pub: dev.x25519_pub_key,
privKey: keyFile.priv_key,
});
await submitTx(tx);
// Optimistic — drop from local list immediately; next load
// reconciles. Chain tx takes ~1 block to commit.
setDevices(prev => prev.filter(d => d.x25519_pub_key !== dev.x25519_pub_key));
} catch (e: any) {
Alert.alert('Unlink failed', humanizeTxError(e));
} finally {
setUnlinking(null);
}
},
},
],
);
}, [keyFile]);
const meX25519 = keyFile?.x25519_pub ?? '';
// Pairing modal state — filled by the operator reading values off the
// new device's /auth/pair screen.
const [pairOpen, setPairOpen] = useState(false);
const [pairCode, setPairCode] = useState('');
const [pairKey, setPairKey] = useState('');
const [pairName, setPairName] = useState('');
const [pairBusy, setPairBusy] = useState(false);
const submitPair = useCallback(async () => {
if (!keyFile) return;
const code = pairCode.replace(/\s+/g, '').trim();
const key = pairKey.replace(/\s+/g, '').trim().toLowerCase();
if (!/^\d{6}$/.test(code)) {
Alert.alert('Invalid code', 'The pairing code is 6 digits.');
return;
}
if (!/^[0-9a-f]{64}$/.test(key)) {
Alert.alert('Invalid key', 'The device key must be 64 hex characters.');
return;
}
const name = pairName.trim() || 'New device';
setPairBusy(true);
try {
// 1. LINK_DEVICE on-chain so senders learn the new pub.
const tx = buildLinkDeviceTx({
from: keyFile.pub_key,
x25519Pub: key,
deviceName: name,
privKey: keyFile.priv_key,
});
await submitTx(tx);
// 2. Ship the handshake payload to the new device. Encrypted for
// its x25519 pub so only it can read — master priv in plaintext
// would be catastrophic, E2E is the whole point.
const payload = JSON.stringify({
v: 1,
type: 'pair-handshake',
code,
master_pub: keyFile.pub_key,
master_priv: keyFile.priv_key,
master_x25519_pub: keyFile.x25519_pub,
});
const { nonce, ciphertext } = encryptMessage(
payload, keyFile.x25519_priv, key,
);
await sendEnvelope({
senderPub: keyFile.x25519_pub,
recipientPub: key,
senderEd25519Pub: keyFile.pub_key,
nonce, ciphertext,
});
// 3. Optimistic local insert so the row shows up without waiting
// for the next pull/refresh round-trip.
setDevices(prev => {
if (prev.some(d => d.x25519_pub_key === key)) return prev;
return [...prev, {
x25519_pub_key: key,
device_name: name,
added_at: Math.floor(Date.now() / 1000),
}];
});
setPairOpen(false);
setPairCode(''); setPairKey(''); setPairName('');
Alert.alert(
'Pairing sent',
'The new device should finish pairing in a few seconds.',
);
} catch (e: any) {
Alert.alert('Pairing failed', humanizeTxError(e));
} finally {
setPairBusy(false);
}
}, [keyFile, pairCode, pairKey, pairName]);
return (
<View style={{ flex: 1, backgroundColor: '#000000', paddingTop: insets.top }}>
<Header
title="Devices"
divider
left={<IconButton icon="chevron-back" size={36} onPress={() => safeBack()} />}
/>
<ScrollView
contentContainerStyle={{ padding: 14, paddingBottom: insets.bottom + 30 }}
refreshControl={
<RefreshControl
refreshing={refreshing}
onRefresh={() => load(true)}
tintColor="#1d9bf0"
/>
}
>
<Text style={{ color: '#8b8b8b', fontSize: 12, lineHeight: 17, marginBottom: 14 }}>
Every linked device has its own encryption key. Messages sent to you
are delivered to all active devices.
</Text>
{loading ? (
<View style={{ paddingTop: 60, alignItems: 'center' }}>
<ActivityIndicator color="#1d9bf0" />
</View>
) : devices.length === 0 ? (
<View style={{
paddingTop: 60, alignItems: 'center', paddingHorizontal: 24,
}}>
<Ionicons name="phone-portrait-outline" size={36} color="#3a3a3a" />
<Text style={{
color: '#ffffff', fontSize: 15, fontWeight: '700',
marginTop: 10,
}}>
No devices registered yet
</Text>
<Text style={{
color: '#8b8b8b', fontSize: 13, textAlign: 'center',
marginTop: 6, lineHeight: 19,
}}>
This device auto-registers when the next network-fee is available.
Top up your balance and pull to refresh.
</Text>
</View>
) : (
<View style={{
borderRadius: 14,
backgroundColor: '#0a0a0a',
borderWidth: 1, borderColor: '#1f1f1f',
overflow: 'hidden',
}}>
{devices.map((d, i) => {
const isMe = d.x25519_pub_key === meX25519;
const busy = unlinking === d.x25519_pub_key;
return (
<View key={d.x25519_pub_key}>
{i > 0 && <View style={{ height: 1, backgroundColor: '#1f1f1f' }} />}
<View style={{
flexDirection: 'row', alignItems: 'center',
paddingHorizontal: 14, paddingVertical: 14, gap: 12,
}}>
<Ionicons
name={isMe ? 'phone-portrait' : 'phone-portrait-outline'}
size={22}
color={isMe ? '#1d9bf0' : '#d0d0d0'}
/>
<View style={{ flex: 1, minWidth: 0 }}>
<View style={{ flexDirection: 'row', alignItems: 'center', gap: 6 }}>
<Text
style={{ color: '#ffffff', fontSize: 15, fontWeight: '700' }}
numberOfLines={1}
>
{d.device_name || 'Unnamed device'}
</Text>
{isMe && (
<View style={{
paddingHorizontal: 6, paddingVertical: 1,
borderRadius: 6, backgroundColor: '#0d2540',
}}>
<Text style={{ color: '#1d9bf0', fontSize: 10, fontWeight: '700' }}>
THIS DEVICE
</Text>
</View>
)}
</View>
<Text
style={{
color: '#8b8b8b', fontSize: 11, fontFamily: 'monospace',
marginTop: 3,
}}
numberOfLines={1}
>
{shortPub(d.x25519_pub_key)}
</Text>
<Text style={{ color: '#6a6a6a', fontSize: 11, marginTop: 2 }}>
Linked {formatDate(d.added_at)}
</Text>
</View>
{!isMe && (
<Pressable
onPress={() => onUnlink(d)}
disabled={busy}
style={({ pressed }) => ({
paddingHorizontal: 12, paddingVertical: 7,
borderRadius: 999,
borderWidth: 1, borderColor: '#3a2020',
backgroundColor: pressed ? '#2a1414' : 'transparent',
opacity: busy ? 0.5 : 1,
})}
>
{busy ? (
<ActivityIndicator size="small" color="#ff6b6b" />
) : (
<Text style={{ color: '#ff6b6b', fontSize: 12, fontWeight: '700' }}>
Unlink
</Text>
)}
</Pressable>
)}
</View>
</View>
);
})}
</View>
)}
{/* Link new device — opens a modal with Code + DeviceKey inputs
that the operator transcribes from the new device's
/auth/pair screen. */}
<View style={{ marginTop: 18 }}>
<Pressable
onPress={() => setPairOpen(true)}
style={({ pressed }) => ({
paddingVertical: 13, paddingHorizontal: 16,
borderRadius: 14,
backgroundColor: pressed ? '#1a1a1a' : '#0a0a0a',
borderWidth: 1, borderColor: '#1f1f1f',
flexDirection: 'row', alignItems: 'center', gap: 10,
})}
>
<Ionicons name="link-outline" size={18} color="#1d9bf0" />
<View style={{ flex: 1 }}>
<Text style={{ color: '#ffffff', fontSize: 14, fontWeight: '700' }}>
Link new device
</Text>
<Text style={{ color: '#8b8b8b', fontSize: 12, marginTop: 2 }}>
Enter the 6-digit code from the new device
</Text>
</View>
<Ionicons name="chevron-forward" size={18} color="#6a6a6a" />
</Pressable>
</View>
</ScrollView>
{/* ── Pair new device modal ───────────────────────────────────── */}
<Modal
visible={pairOpen}
animationType="fade"
transparent
onRequestClose={() => !pairBusy && setPairOpen(false)}
>
<KeyboardAvoidingView
behavior={Platform.OS === 'ios' ? 'padding' : undefined}
style={{
flex: 1,
backgroundColor: 'rgba(0,0,0,0.7)',
justifyContent: 'center', alignItems: 'center',
paddingHorizontal: 20,
}}
>
<View style={{
width: '100%', maxWidth: 420,
backgroundColor: '#0a0a0a',
borderRadius: 18,
borderWidth: 1, borderColor: '#1f1f1f',
padding: 20, gap: 12,
}}>
<View style={{
flexDirection: 'row', alignItems: 'center',
justifyContent: 'space-between', marginBottom: 4,
}}>
<Text style={{ color: '#ffffff', fontSize: 18, fontWeight: '800' }}>
Link new device
</Text>
<Pressable
onPress={() => !pairBusy && setPairOpen(false)}
hitSlop={8}
>
<Ionicons name="close" size={22} color="#8b8b8b" />
</Pressable>
</View>
<Text style={{ color: '#8b8b8b', fontSize: 12, lineHeight: 18 }}>
Open the new device, tap <Text style={{ color: '#ffffff' }}>Pair</Text> on
the welcome screen, then transcribe the code + device key shown there.
</Text>
<PairInput
label="6-digit code"
value={pairCode}
onChangeText={setPairCode}
placeholder="000000"
keyboardType="number-pad"
maxLength={6}
monospace
/>
<PairInput
label="Device key"
value={pairKey}
onChangeText={setPairKey}
placeholder="64 hex chars"
autoCapitalize="none"
maxLength={64}
monospace
/>
<PairInput
label="Name for this device (optional)"
value={pairName}
onChangeText={setPairName}
placeholder="e.g. Alice's laptop"
maxLength={64}
/>
<View style={{
flexDirection: 'row', justifyContent: 'flex-end',
gap: 10, marginTop: 8,
}}>
<Pressable
onPress={() => setPairOpen(false)}
disabled={pairBusy}
style={({ pressed }) => ({
paddingHorizontal: 16, paddingVertical: 10,
borderRadius: 999,
backgroundColor: pressed ? '#1a1a1a' : 'transparent',
opacity: pairBusy ? 0.5 : 1,
})}
>
<Text style={{ color: '#8b8b8b', fontSize: 14, fontWeight: '700' }}>
Cancel
</Text>
</Pressable>
<Pressable
onPress={submitPair}
disabled={pairBusy}
style={({ pressed }) => ({
paddingHorizontal: 18, paddingVertical: 10,
borderRadius: 999,
backgroundColor: pressed ? '#1580c8' : '#1d9bf0',
opacity: pairBusy ? 0.7 : 1,
minWidth: 90, alignItems: 'center',
})}
>
{pairBusy ? (
<ActivityIndicator size="small" color="#ffffff" />
) : (
<Text style={{ color: '#ffffff', fontSize: 14, fontWeight: '700' }}>
Link
</Text>
)}
</Pressable>
</View>
</View>
</KeyboardAvoidingView>
</Modal>
</View>
);
}
function PairInput({
label, value, onChangeText, placeholder, keyboardType, autoCapitalize,
maxLength, monospace,
}: {
label: string;
value: string;
onChangeText: (v: string) => void;
placeholder?: string;
keyboardType?: 'default' | 'number-pad';
autoCapitalize?: 'none' | 'sentences';
maxLength?: number;
monospace?: boolean;
}) {
return (
<View>
<Text style={{
color: '#8b8b8b', fontSize: 11, fontWeight: '700',
textTransform: 'uppercase', letterSpacing: 1, marginBottom: 6,
}}>
{label}
</Text>
<TextInput
value={value}
onChangeText={onChangeText}
placeholder={placeholder}
placeholderTextColor="#3a3a3a"
keyboardType={keyboardType}
autoCapitalize={autoCapitalize ?? 'sentences'}
autoCorrect={false}
maxLength={maxLength}
style={{
color: '#ffffff', fontSize: monospace ? 13 : 14,
fontFamily: monospace ? 'monospace' : undefined,
backgroundColor: '#000000',
borderRadius: 10,
paddingHorizontal: 12, paddingVertical: 10,
borderWidth: 1, borderColor: '#1f1f1f',
}}
/>
</View>
);
}