| 1 | import Foundation |
| 2 | import Security |
| 3 | |
| 4 | // Thread keys + display titles shared with the notification extension: the APNs |
| 5 | // payload is ciphertext (the server never sees plaintext), so the NSE decrypts |
| 6 | // on-device with the key stored here. The app refreshes entries whenever a |
| 7 | // ThreadStore loads; the NSE only reads. |
| 8 | // |
| 9 | // Storage is the keychain (they're message keys), accessible after first unlock |
| 10 | // so a notification arriving while the phone is locked can still be decrypted. |
| 11 | // On properly-signed builds both targets opt into the same keychain access |
| 12 | // group; ad-hoc/dev builds can't mint that entitlement, so writes retry without |
| 13 | // the group (simulator keychains aren't segmented, which is what makes the |
| 14 | // simulator end-to-end push test work). |
| 15 | public enum SharedThreadKeys { |
| 16 | public struct Entry: Codable { |
| 17 | public let key: Data // raw AES-GCM thread key |
| 18 | public let title: String // decrypted chat title (never stored server-side) |
| 19 | public let origin: String // owning instance, for notification → chat routing |
| 20 | public let group: Bool // groups prefix the sender name in the banner |
| 21 | // This user's uid on the owning instance: the NSE compares it to a |
| 22 | // reaction event's targetUid to show "X reacted" only to the reacted-to |
| 23 | // message's author. Optional so entries parked by older builds still |
| 24 | // decode (they fall back to the quiet non-author path). |
| 25 | public var myUid: String? |
| 26 | // This thread's members, uid → the name THIS member shows for them |
| 27 | // (per-viewer names resolved, #577) — the NSE names senders with it |
| 28 | // instead of the payload's snapshot. Optional: older entries decode |
| 29 | // and fall back to the snapshot. |
| 30 | public var names: [String: String]? |
| 31 | // This user muted the chat (#578): the NSE delivers its pushes as |
| 32 | // passive, silent entries. Belt-and-braces — the server already skips |
| 33 | // pushes for muted threads; this covers entries parked before an |
| 34 | // unmute raced a stale park, and older servers. Optional so entries |
| 35 | // parked by older builds decode as unmuted. |
| 36 | public var muted: Bool? |
| 37 | } |
| 38 | |
| 39 | private static let service = "com.lchat.client.threadkeys" |
| 40 | // TeamID prefix + shared suffix; only valid with the keychain-sharing |
| 41 | // entitlement (paid signing). See the go-live notes in ios/README.md. |
| 42 | private static let accessGroup = "J5NDF5PCD8.com.elevenmessenger.messenger.shared" |
| 43 | |
| 44 | // Every ThreadStore.refresh re-parks every thread — but a Keychain write |
| 45 | // costs 5-50ms ON MAIN, so a busy instance stalled scrolling for hundreds |
| 46 | // of ms per refresh. Skip unchanged payloads (the overwhelmingly common |
| 47 | // case) and do the real writes off the main thread (Keychain is |
| 48 | // thread-safe). |
| 49 | private static var savedFingerprints: [String: Int] = [:] |
| 50 | private static let fingerprintLock = NSLock() |
| 51 | private static let writeQueue = DispatchQueue(label: "shared-thread-keys", qos: .utility) |
| 52 | |
| 53 | public static func save(threadID: String, entry: Entry) { |
| 54 | guard let data = try? JSONEncoder().encode(entry) else { return } |
| 55 | let fingerprint = data.hashValue |
| 56 | fingerprintLock.lock() |
| 57 | let unchanged = savedFingerprints[threadID] == fingerprint |
| 58 | if !unchanged { savedFingerprints[threadID] = fingerprint } |
| 59 | fingerprintLock.unlock() |
| 60 | if unchanged { return } |
| 61 | writeQueue.async { write(threadID: threadID, data: data) } |
| 62 | } |
| 63 | |
| 64 | private static func write(threadID: String, data: Data) { |
| 65 | var base: [String: Any] = [ |
| 66 | kSecClass as String: kSecClassGenericPassword, |
| 67 | kSecAttrService as String: service, |
| 68 | kSecAttrAccount as String: threadID, |
| 69 | kSecUseDataProtectionKeychain as String: true, |
| 70 | kSecAttrAccessGroup as String: accessGroup, |
| 71 | ] |
| 72 | base[kSecAttrAccount as String] = threadID |
| 73 | var add = base |
| 74 | add[kSecValueData as String] = data |
| 75 | add[kSecAttrAccessible as String] = kSecAttrAccessibleAfterFirstUnlock |
| 76 | SecItemDelete(base as CFDictionary) |
| 77 | if SecItemAdd(add as CFDictionary, nil) == errSecSuccess { return } |
| 78 | // No sharing entitlement (dev build): keep it app-local so the rest of |
| 79 | // the flow still works; the NSE then falls back to the generic banner. |
| 80 | base.removeValue(forKey: kSecAttrAccessGroup as String) |
| 81 | add.removeValue(forKey: kSecAttrAccessGroup as String) |
| 82 | SecItemDelete(base as CFDictionary) |
| 83 | SecItemAdd(add as CFDictionary, nil) |
| 84 | } |
| 85 | |
| 86 | public static func lookup(threadID: String) -> Entry? { |
| 87 | for withGroup in [true, false] { |
| 88 | var query: [String: Any] = [ |
| 89 | kSecClass as String: kSecClassGenericPassword, |
| 90 | kSecAttrService as String: service, |
| 91 | kSecAttrAccount as String: threadID, |
| 92 | kSecUseDataProtectionKeychain as String: true, |
| 93 | kSecReturnData as String: true, |
| 94 | kSecMatchLimit as String: kSecMatchLimitOne, |
| 95 | ] |
| 96 | if withGroup { query[kSecAttrAccessGroup as String] = accessGroup } |
| 97 | var item: CFTypeRef? |
| 98 | if SecItemCopyMatching(query as CFDictionary, &item) == errSecSuccess, |
| 99 | let data = item as? Data, |
| 100 | let entry = try? JSONDecoder().decode(Entry.self, from: data) { |
| 101 | return entry |
| 102 | } |
| 103 | } |
| 104 | return nil |
| 105 | } |
| 106 | } |
| 107 | |
| 108 | // The muted-people set (#578), parked for the notification extension the way |
| 109 | // SharedThreadKeys parks thread keys: the NSE decides AFTER decrypting whether |
| 110 | // the sender is muted (the uid rides inside the ciphertext, so the server — |
| 111 | // which never learns who's muted — can't skip these pushes for us), and goes |
| 112 | // passive when they are. One entry per instance origin; plaintext uids are |
| 113 | // fine here — the shared keychain is the same trust domain as the parked |
| 114 | // thread keys beside them. Refreshed whenever the prefs blob loads or saves. |
| 115 | public enum SharedMutedPeople { |
| 116 | private static let service = "com.lchat.client.mutedpeople" |
| 117 | private static let accessGroup = "J5NDF5PCD8.com.elevenmessenger.messenger.shared" |
| 118 | |
| 119 | // Same skip-unchanged + off-main write posture as SharedThreadKeys — |
| 120 | // saves fire on every prefs load and a Keychain write costs main-thread ms. |
| 121 | private static var savedFingerprints: [String: Int] = [:] |
| 122 | private static let fingerprintLock = NSLock() |
| 123 | private static let writeQueue = DispatchQueue(label: "shared-muted-people", qos: .utility) |
| 124 | |
| 125 | public static func save(origin: String, uids: Set<String>) { |
| 126 | guard let data = try? JSONEncoder().encode(uids.sorted()) else { return } |
| 127 | let fingerprint = data.hashValue |
| 128 | fingerprintLock.lock() |
| 129 | let unchanged = savedFingerprints[origin] == fingerprint |
| 130 | if !unchanged { savedFingerprints[origin] = fingerprint } |
| 131 | fingerprintLock.unlock() |
| 132 | if unchanged { return } |
| 133 | writeQueue.async { write(origin: origin, data: data) } |
| 134 | } |
| 135 | |
| 136 | private static func write(origin: String, data: Data) { |
| 137 | var base: [String: Any] = [ |
| 138 | kSecClass as String: kSecClassGenericPassword, |
| 139 | kSecAttrService as String: service, |
| 140 | kSecAttrAccount as String: origin, |
| 141 | kSecUseDataProtectionKeychain as String: true, |
| 142 | kSecAttrAccessGroup as String: accessGroup, |
| 143 | ] |
| 144 | var add = base |
| 145 | add[kSecValueData as String] = data |
| 146 | add[kSecAttrAccessible as String] = kSecAttrAccessibleAfterFirstUnlock |
| 147 | SecItemDelete(base as CFDictionary) |
| 148 | if SecItemAdd(add as CFDictionary, nil) == errSecSuccess { return } |
| 149 | // No sharing entitlement (dev build): keep it app-local; the NSE then |
| 150 | // simply sees nobody muted — the banner degrades, never errors. |
| 151 | base.removeValue(forKey: kSecAttrAccessGroup as String) |
| 152 | add.removeValue(forKey: kSecAttrAccessGroup as String) |
| 153 | SecItemDelete(base as CFDictionary) |
| 154 | SecItemAdd(add as CFDictionary, nil) |
| 155 | } |
| 156 | |
| 157 | public static func lookup(origin: String) -> Set<String> { |
| 158 | for withGroup in [true, false] { |
| 159 | var query: [String: Any] = [ |
| 160 | kSecClass as String: kSecClassGenericPassword, |
| 161 | kSecAttrService as String: service, |
| 162 | kSecAttrAccount as String: origin, |
| 163 | kSecUseDataProtectionKeychain as String: true, |
| 164 | kSecReturnData as String: true, |
| 165 | kSecMatchLimit as String: kSecMatchLimitOne, |
| 166 | ] |
| 167 | if withGroup { query[kSecAttrAccessGroup as String] = accessGroup } |
| 168 | var item: CFTypeRef? |
| 169 | if SecItemCopyMatching(query as CFDictionary, &item) == errSecSuccess, |
| 170 | let data = item as? Data, |
| 171 | let uids = try? JSONDecoder().decode([String].self, from: data) { |
| 172 | return Set(uids) |
| 173 | } |
| 174 | } |
| 175 | return [] |
| 176 | } |
| 177 | } |
| 178 | |
amadan