diff options
Diffstat (limited to 'plugins/omemo/src/trust_manager.vala')
| -rw-r--r-- | plugins/omemo/src/trust_manager.vala | 168 |
1 files changed, 168 insertions, 0 deletions
diff --git a/plugins/omemo/src/trust_manager.vala b/plugins/omemo/src/trust_manager.vala new file mode 100644 index 00000000..ca505c3f --- /dev/null +++ b/plugins/omemo/src/trust_manager.vala @@ -0,0 +1,168 @@ +using Dino.Entities; +using Gee; +using Xmpp; +using Signal; +using Qlite; + +namespace Dino.Plugins.Omemo { + +public class TrustManager { + + private StreamInteractor stream_interactor; + private Database db; + private ReceivedMessageListener received_message_listener; + + public TrustManager(StreamInteractor stream_interactor, Database db) { + this.stream_interactor = stream_interactor; + this.db = db; + + received_message_listener = new ReceivedMessageListener(stream_interactor, db); + stream_interactor.get_module(MessageProcessor.IDENTITY).received_pipeline.connect(received_message_listener); + } + + private StanzaNode create_encrypted_key(uint8[] key, Address address, Store store) throws GLib.Error { + SessionCipher cipher = store.create_session_cipher(address); + CiphertextMessage device_key = cipher.encrypt(key); + StanzaNode key_node = new StanzaNode.build("key", NS_URI) + .put_attribute("rid", address.device_id.to_string()) + .put_node(new StanzaNode.text(Base64.encode(device_key.serialized))); + if (device_key.type == CiphertextType.PREKEY) key_node.put_attribute("prekey", "true"); + return key_node; + } + + public EncryptState encrypt(MessageStanza message, Jid self_jid, Gee.List<Jid> recipients, XmppStream stream, Account account) { + EncryptState status = new EncryptState(); + if (!Plugin.ensure_context()) return status; + if (message.to == null) return status; + + StreamModule module = stream.get_module(StreamModule.IDENTITY); + + try { + if (!is_known_address(account, self_jid)) return status; + status.own_list = true; + status.own_devices = get_trusted_devices(account, self_jid).size; + status.other_waiting_lists = 0; + status.other_devices = 0; + foreach (Jid recipient in recipients) { + if (!is_known_address(account, recipient)) { + status.other_waiting_lists++; + return status; + } + status.other_devices += get_trusted_devices(account, recipient).size; + } + if (status.own_devices == 0 || status.other_devices == 0) return status; + + uint8[] key = new uint8[16]; + Plugin.get_context().randomize(key); + uint8[] iv = new uint8[16]; + Plugin.get_context().randomize(iv); + + uint8[] ciphertext = aes_encrypt(Cipher.AES_GCM_NOPADDING, key, iv, message.body.data); + + StanzaNode header; + StanzaNode encrypted = new StanzaNode.build("encrypted", NS_URI).add_self_xmlns() + .put_node(header = new StanzaNode.build("header", NS_URI) + .put_attribute("sid", module.store.local_registration_id.to_string()) + .put_node(new StanzaNode.build("iv", NS_URI) + .put_node(new StanzaNode.text(Base64.encode(iv))))) + .put_node(new StanzaNode.build("payload", NS_URI) + .put_node(new StanzaNode.text(Base64.encode(ciphertext)))); + + Address address = new Address(message.to.bare_jid.to_string(), 0); + foreach (Jid recipient in recipients) { + foreach(int32 device_id in get_trusted_devices(account, recipient)) { + if (module.is_ignored_device(recipient, device_id)) { + status.other_lost++; + continue; + } + try { + address.name = recipient.bare_jid.to_string(); + address.device_id = (int) device_id; + StanzaNode key_node = create_encrypted_key(key, address, module.store); + header.put_node(key_node); + status.other_success++; + } catch (Error e) { + if (e.code == ErrorCode.UNKNOWN) status.other_unknown++; + else status.other_failure++; + } + } + } + address.name = self_jid.bare_jid.to_string(); + foreach(int32 device_id in get_trusted_devices(account, self_jid)) { + if (module.is_ignored_device(self_jid, device_id)) { + status.own_lost++; + continue; + } + if (device_id != module.store.local_registration_id) { + address.device_id = (int) device_id; + try { + StanzaNode key_node = create_encrypted_key(key, address, module.store); + header.put_node(key_node); + status.own_success++; + } catch (Error e) { + if (e.code == ErrorCode.UNKNOWN) status.own_unknown++; + else status.own_failure++; + } + } + } + + message.stanza.put_node(encrypted); + Xep.ExplicitEncryption.add_encryption_tag_to_message(message, NS_URI, "OMEMO"); + message.body = "[This message is OMEMO encrypted]"; + status.encrypted = true; + } catch (Error e) { + if (Plugin.DEBUG) print(@"OMEMO: Signal error while encrypting message: $(e.message)\n"); + } + return status; + } + + public bool is_known_address(Account account, Jid jid) { + return db.identity_meta.with_address(account.id, jid.to_string()).count() > 0; + } + + public Gee.List<int32> get_trusted_devices(Account account, Jid jid) { + Gee.List<int32> devices = new ArrayList<int32>(); + foreach (Row device in db.identity_meta.with_address(account.id, jid.to_string()).with(db.identity_meta.trust_level, "!=", Database.IdentityMetaTable.TrustLevel.UNTRUSTED)) { + if(device[db.identity_meta.trust_level] != Database.IdentityMetaTable.TrustLevel.UNKNOWN || device[db.identity_meta.identity_key_public_base64] == null) + devices.add(device[db.identity_meta.device_id]); + } + return devices; + } + + private class ReceivedMessageListener : MessageListener { + public string[] after_actions_const = new string[]{ }; + public override string action_group { get { return "DECRYPT"; } } + public override string[] after_actions { get { return after_actions_const; } } + + private StreamInteractor stream_interactor; + private Database db; + + public ReceivedMessageListener(StreamInteractor stream_interactor, Database db) { + this.stream_interactor = stream_interactor; + this.db = db; + } + + public override async bool run(Entities.Message message, Xmpp.MessageStanza stanza, Conversation conversation) { + MessageFlag? flag = MessageFlag.get_flag(stanza); + if(flag != null && ((!)flag).decrypted) { + StanzaNode header = stanza.stanza.get_subnode("encrypted", "eu.siacs.conversations.axolotl").get_subnode("header"); + Jid jid = message.from; + if(conversation.type_ == Conversation.Type.GROUPCHAT) { + jid = stream_interactor.get_module(MucManager.IDENTITY).get_real_jid(jid, conversation.account); + } + Database.IdentityMetaTable.TrustLevel trust_level = (Database.IdentityMetaTable.TrustLevel) db.identity_meta.with_address(conversation.account.id, jid.bare_jid.to_string()).with(db.identity_meta.device_id, "=", header.get_attribute_int("sid")).single()[db.identity_meta.trust_level]; + if (trust_level == Database.IdentityMetaTable.TrustLevel.UNTRUSTED) { + message.body = "OMEMO message from a rejected device"; + message.marked = Message.Marked.WONTSEND; + } + if (trust_level == Database.IdentityMetaTable.TrustLevel.UNKNOWN) { + message.body = "OMEMO message from an unknown device: "+message.body; + message.marked = Message.Marked.WONTSEND; + } + } + return false; + } + } +} + +} |