From 421f43dd8bd993eb88581e1b5011cc061ceb4fc8 Mon Sep 17 00:00:00 2001 From: fiaxh Date: Sun, 25 Apr 2021 19:49:10 +0200 Subject: Add support for OMEMO call encryption --- plugins/omemo/src/logic/decrypt.vala | 210 ++++++++++++++++++++ plugins/omemo/src/logic/encrypt.vala | 131 +++++++++++++ plugins/omemo/src/logic/encrypt_state.vala | 24 --- plugins/omemo/src/logic/manager.vala | 16 +- plugins/omemo/src/logic/trust_manager.vala | 302 +---------------------------- 5 files changed, 351 insertions(+), 332 deletions(-) create mode 100644 plugins/omemo/src/logic/decrypt.vala create mode 100644 plugins/omemo/src/logic/encrypt.vala delete mode 100644 plugins/omemo/src/logic/encrypt_state.vala (limited to 'plugins/omemo/src/logic') diff --git a/plugins/omemo/src/logic/decrypt.vala b/plugins/omemo/src/logic/decrypt.vala new file mode 100644 index 00000000..3cdacbf7 --- /dev/null +++ b/plugins/omemo/src/logic/decrypt.vala @@ -0,0 +1,210 @@ +using Dino.Entities; +using Qlite; +using Gee; +using Signal; +using Xmpp; + +namespace Dino.Plugins.Omemo { + + public class OmemoDecryptor : Xep.Omemo.OmemoDecryptor { + + private Account account; + private Store store; + private Database db; + private StreamInteractor stream_interactor; + private TrustManager trust_manager; + + public override uint32 own_device_id { get { return store.local_registration_id; }} + + public OmemoDecryptor(Account account, StreamInteractor stream_interactor, TrustManager trust_manager, Database db, Store store) { + this.account = account; + this.stream_interactor = stream_interactor; + this.trust_manager = trust_manager; + this.db = db; + this.store = store; + } + + public bool decrypt_message(Entities.Message message, Xmpp.MessageStanza stanza, Conversation conversation) { + StanzaNode? encrypted_node = stanza.stanza.get_subnode("encrypted", NS_URI); + if (encrypted_node == null || MessageFlag.get_flag(stanza) != null || stanza.from == null) return false; + + if (message.body == null && Xep.ExplicitEncryption.get_encryption_tag(stanza) == NS_URI) { + message.body = "[This message is OMEMO encrypted]"; // TODO temporary + } + if (!Plugin.ensure_context()) return false; + int identity_id = db.identity.get_id(conversation.account.id); + + MessageFlag flag = new MessageFlag(); + stanza.add_flag(flag); + + Xep.Omemo.ParsedData? data = parse_node(encrypted_node); + if (data == null || data.ciphertext == null) return false; + + + foreach (Bytes encr_key in data.our_potential_encrypted_keys.keys) { + data.is_prekey = data.our_potential_encrypted_keys[encr_key]; + data.encrypted_key = encr_key.get_data(); + Gee.List possible_jids = get_potential_message_jids(message, data, identity_id); + if (possible_jids.size == 0) { + debug("Received message from unknown entity with device id %d", data.sid); + } + + foreach (Jid possible_jid in possible_jids) { + try { + uint8[] key = decrypt_key(data, possible_jid); + string cleartext = arr_to_str(aes_decrypt(Cipher.AES_GCM_NOPADDING, key, data.iv, data.ciphertext)); + + // If we figured out which real jid a message comes from due to decryption working, save it + if (conversation.type_ == Conversation.Type.GROUPCHAT && message.real_jid == null) { + message.real_jid = possible_jid; + } + + trust_manager.message_device_id_map[message] = data.sid; + message.body = cleartext; + message.encryption = Encryption.OMEMO; + return true; + } catch (Error e) { + debug("Decrypting message from %s/%d failed: %s", possible_jid.to_string(), data.sid, e.message); + } + } + } + + if ( + encrypted_node.get_deep_string_content("payload") != null && // Ratchet forwarding doesn't contain payload and might not include us, which is ok + data.our_potential_encrypted_keys.size == 0 && // The message was not encrypted to us + stream_interactor.module_manager.get_module(message.account, StreamModule.IDENTITY).store.local_registration_id != data.sid // Message from this device. Never encrypted to itself. + ) { + db.identity_meta.update_last_message_undecryptable(identity_id, data.sid, message.time); + trust_manager.bad_message_state_updated(conversation.account, message.from, data.sid); + } + + debug("Received OMEMO encryped message that could not be decrypted."); + return false; + } + + public Gee.List get_potential_message_jids(Entities.Message message, Xmpp.Xep.Omemo.ParsedData data, int identity_id) { + Gee.List possible_jids = new ArrayList(); + if (message.type_ == Message.Type.CHAT) { + possible_jids.add(message.from.bare_jid); + } else { + if (message.real_jid != null) { + possible_jids.add(message.real_jid.bare_jid); + } else if (data.is_prekey) { + // pre key messages do store the identity key, so we can use that to find the real jid + PreKeySignalMessage msg = Plugin.get_context().deserialize_pre_key_signal_message(data.encrypted_key); + string identity_key = Base64.encode(msg.identity_key.serialize()); + foreach (Row row in db.identity_meta.get_with_device_id(identity_id, data.sid).with(db.identity_meta.identity_key_public_base64, "=", identity_key)) { + try { + possible_jids.add(new Jid(row[db.identity_meta.address_name])); + } catch (InvalidJidError e) { + warning("Ignoring invalid jid from database: %s", e.message); + } + } + } else { + // If we don't know the device name (MUC history w/o MAM), test decryption with all keys with fitting device id + foreach (Row row in db.identity_meta.get_with_device_id(identity_id, data.sid)) { + try { + possible_jids.add(new Jid(row[db.identity_meta.address_name])); + } catch (InvalidJidError e) { + warning("Ignoring invalid jid from database: %s", e.message); + } + } + } + } + return possible_jids; + } + + public override uint8[] decrypt_key(Xmpp.Xep.Omemo.ParsedData data, Jid from_jid) throws GLib.Error { + int sid = data.sid; + uint8[] ciphertext = data.ciphertext; + uint8[] encrypted_key = data.encrypted_key; + + Address address = new Address(from_jid.to_string(), sid); + uint8[] key; + + if (data.is_prekey) { + int identity_id = db.identity.get_id(account.id); + PreKeySignalMessage msg = Plugin.get_context().deserialize_pre_key_signal_message(encrypted_key); + string identity_key = Base64.encode(msg.identity_key.serialize()); + + bool ok = update_db_for_prekey(identity_id, identity_key, from_jid, sid); + if (!ok) return null; + + debug("Starting new session for decryption with device from %s/%d", from_jid.to_string(), sid); + SessionCipher cipher = store.create_session_cipher(address); + key = cipher.decrypt_pre_key_signal_message(msg); + // TODO: Finish session + } else { + debug("Continuing session for decryption with device from %s/%d", from_jid.to_string(), sid); + SignalMessage msg = Plugin.get_context().deserialize_signal_message(encrypted_key); + SessionCipher cipher = store.create_session_cipher(address); + key = cipher.decrypt_signal_message(msg); + } + + if (key.length >= 32) { + int authtaglength = key.length - 16; + uint8[] new_ciphertext = new uint8[ciphertext.length + authtaglength]; + uint8[] new_key = new uint8[16]; + Memory.copy(new_ciphertext, ciphertext, ciphertext.length); + Memory.copy((uint8*)new_ciphertext + ciphertext.length, (uint8*)key + 16, authtaglength); + Memory.copy(new_key, key, 16); + data.ciphertext = new_ciphertext; + key = new_key; + } + + return key; + } + + public override string decrypt(uint8[] ciphertext, uint8[] key, uint8[] iv) throws GLib.Error { + return arr_to_str(aes_decrypt(Cipher.AES_GCM_NOPADDING, key, iv, ciphertext)); + } + + private bool update_db_for_prekey(int identity_id, string identity_key, Jid from_jid, int sid) { + Row? device = db.identity_meta.get_device(identity_id, from_jid.to_string(), sid); + if (device != null && device[db.identity_meta.identity_key_public_base64] != null) { + if (device[db.identity_meta.identity_key_public_base64] != identity_key) { + critical("Tried to use a different identity key for a known device id."); + return false; + } + } else { + debug("Learn new device from incoming message from %s/%d", from_jid.to_string(), sid); + bool blind_trust = db.trust.get_blind_trust(identity_id, from_jid.to_string(), true); + if (db.identity_meta.insert_device_session(identity_id, from_jid.to_string(), sid, identity_key, blind_trust ? TrustLevel.TRUSTED : TrustLevel.UNKNOWN) < 0) { + critical("Failed learning a device."); + return false; + } + + XmppStream? stream = stream_interactor.get_stream(account); + if (device == null && stream != null) { + stream.get_module(StreamModule.IDENTITY).request_user_devicelist.begin(stream, from_jid); + } + } + return true; + } + + private string arr_to_str(uint8[] arr) { + // null-terminate the array + uint8[] rarr = new uint8[arr.length+1]; + Memory.copy(rarr, arr, arr.length); + return (string)rarr; + } + } + + public class DecryptMessageListener : 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 HashMap decryptors; + + public DecryptMessageListener(HashMap decryptors) { + this.decryptors = decryptors; + } + + public override async bool run(Entities.Message message, Xmpp.MessageStanza stanza, Conversation conversation) { + decryptors[message.account].decrypt_message(message, stanza, conversation); + return false; + } + } +} + diff --git a/plugins/omemo/src/logic/encrypt.vala b/plugins/omemo/src/logic/encrypt.vala new file mode 100644 index 00000000..cd994c3a --- /dev/null +++ b/plugins/omemo/src/logic/encrypt.vala @@ -0,0 +1,131 @@ +using Gee; +using Signal; +using Dino.Entities; +using Xmpp; +using Xmpp.Xep.Omemo; + +namespace Dino.Plugins.Omemo { + + public class OmemoEncryptor : Xep.Omemo.OmemoEncryptor { + + private Account account; + private Store store; + private TrustManager trust_manager; + + public override uint32 own_device_id { get { return store.local_registration_id; }} + + public OmemoEncryptor(Account account, TrustManager trust_manager, Store store) { + this.account = account; + this.trust_manager = trust_manager; + this.store = store; + } + + public override Xep.Omemo.EncryptionData encrypt_plaintext(string plaintext) throws GLib.Error { + const uint KEY_SIZE = 16; + const uint IV_SIZE = 12; + + //Create a key and use it to encrypt the message + uint8[] key = new uint8[KEY_SIZE]; + Plugin.get_context().randomize(key); + uint8[] iv = new uint8[IV_SIZE]; + Plugin.get_context().randomize(iv); + + uint8[] aes_encrypt_result = aes_encrypt(Cipher.AES_GCM_NOPADDING, key, iv, plaintext.data); + uint8[] ciphertext = aes_encrypt_result[0:aes_encrypt_result.length - 16]; + uint8[] tag = aes_encrypt_result[aes_encrypt_result.length - 16:aes_encrypt_result.length]; + uint8[] keytag = new uint8[key.length + tag.length]; + Memory.copy(keytag, key, key.length); + Memory.copy((uint8*)keytag + key.length, tag, tag.length); + + var ret = new Xep.Omemo.EncryptionData(own_device_id); + ret.ciphertext = ciphertext; + ret.keytag = keytag; + ret.iv = iv; + return ret; + } + + public EncryptState encrypt(MessageStanza message, Jid self_jid, Gee.List recipients, XmppStream stream) { + + EncryptState status = new EncryptState(); + if (!Plugin.ensure_context()) return status; + if (message.to == null) return status; + + try { + EncryptionData enc_data = encrypt_plaintext(message.body); + status = encrypt_key_to_recipients(enc_data, self_jid, recipients, stream); + + message.stanza.put_node(enc_data.get_encrypted_node()); + Xep.ExplicitEncryption.add_encryption_tag_to_message(message, NS_URI, "OMEMO"); + message.body = "[This message is OMEMO encrypted]"; + status.encrypted = true; + } catch (Error e) { + warning(@"Signal error while encrypting message: $(e.message)\n"); + message.body = "[OMEMO encryption failed]"; + status.encrypted = false; + } + return status; + } + + internal EncryptState encrypt_key_to_recipients(EncryptionData enc_data, Jid self_jid, Gee.List recipients, XmppStream stream) throws Error { + EncryptState status = new EncryptState(); + + //Check we have the bundles and device lists needed to send the message + if (!trust_manager.is_known_address(account, self_jid)) return status; + status.own_list = true; + status.own_devices = trust_manager.get_trusted_devices(account, self_jid).size; + status.other_waiting_lists = 0; + status.other_devices = 0; + foreach (Jid recipient in recipients) { + if (!trust_manager.is_known_address(account, recipient)) { + status.other_waiting_lists++; + } + if (status.other_waiting_lists > 0) return status; + status.other_devices += trust_manager.get_trusted_devices(account, recipient).size; + } + if (status.own_devices == 0 || status.other_devices == 0) return status; + + + //Encrypt the key for each recipient's device individually + foreach (Jid recipient in recipients) { + EncryptionResult enc_res = encrypt_key_to_recipient(stream, enc_data, recipient); + status.add_result(enc_res, false); + } + + // Encrypt the key for each own device + EncryptionResult enc_res = encrypt_key_to_recipient(stream, enc_data, self_jid); + status.add_result(enc_res, true); + + return status; + } + + public override EncryptionResult encrypt_key_to_recipient(XmppStream stream, Xep.Omemo.EncryptionData enc_data, Jid recipient) throws GLib.Error { + var result = new EncryptionResult(); + StreamModule module = stream.get_module(StreamModule.IDENTITY); + + foreach(int32 device_id in trust_manager.get_trusted_devices(account, recipient)) { + if (module.is_ignored_device(recipient, device_id)) { + result.lost++; + continue; + } + try { + encrypt_key(enc_data, recipient, device_id); + result.success++; + } catch (Error e) { + if (e.code == ErrorCode.UNKNOWN) result.unknown++; + else result.failure++; + } + } + return result; + } + + public override void encrypt_key(Xep.Omemo.EncryptionData encryption_data, Jid jid, int32 device_id) throws GLib.Error { + Address address = new Address(jid.to_string(), device_id); + SessionCipher cipher = store.create_session_cipher(address); + CiphertextMessage device_key = cipher.encrypt(encryption_data.keytag); + address.device_id = 0; + debug("Created encrypted key for %s/%d", jid.to_string(), device_id); + + encryption_data.add_device_key(device_id, device_key.serialized, device_key.type == CiphertextType.PREKEY); + } + } +} \ No newline at end of file diff --git a/plugins/omemo/src/logic/encrypt_state.vala b/plugins/omemo/src/logic/encrypt_state.vala deleted file mode 100644 index fd72faf4..00000000 --- a/plugins/omemo/src/logic/encrypt_state.vala +++ /dev/null @@ -1,24 +0,0 @@ -namespace Dino.Plugins.Omemo { - -public class EncryptState { - public bool encrypted { get; internal set; } - public int other_devices { get; internal set; } - public int other_success { get; internal set; } - public int other_lost { get; internal set; } - public int other_unknown { get; internal set; } - public int other_failure { get; internal set; } - public int other_waiting_lists { get; internal set; } - - public int own_devices { get; internal set; } - public int own_success { get; internal set; } - public int own_lost { get; internal set; } - public int own_unknown { get; internal set; } - public int own_failure { get; internal set; } - public bool own_list { get; internal set; } - - public string to_string() { - return @"EncryptState (encrypted=$encrypted, other=(devices=$other_devices, success=$other_success, lost=$other_lost, unknown=$other_unknown, failure=$other_failure, waiting_lists=$other_waiting_lists, own=(devices=$own_devices, success=$own_success, lost=$own_lost, unknown=$own_unknown, failure=$own_failure, list=$own_list))"; - } -} - -} diff --git a/plugins/omemo/src/logic/manager.vala b/plugins/omemo/src/logic/manager.vala index 64b117c7..5552e212 100644 --- a/plugins/omemo/src/logic/manager.vala +++ b/plugins/omemo/src/logic/manager.vala @@ -13,11 +13,12 @@ public class Manager : StreamInteractionModule, Object { private StreamInteractor stream_interactor; private Database db; private TrustManager trust_manager; + private HashMap encryptors; private Map message_states = new HashMap(Entities.Message.hash_func, Entities.Message.equals_func); private class MessageState { public Entities.Message msg { get; private set; } - public EncryptState last_try { get; private set; } + public Xep.Omemo.EncryptState last_try { get; private set; } public int waiting_other_sessions { get; set; } public int waiting_own_sessions { get; set; } public bool waiting_own_devicelist { get; set; } @@ -26,11 +27,11 @@ public class Manager : StreamInteractionModule, Object { public bool will_send_now { get; private set; } public bool active_send_attempt { get; set; } - public MessageState(Entities.Message msg, EncryptState last_try) { + public MessageState(Entities.Message msg, Xep.Omemo.EncryptState last_try) { update_from_encrypt_status(msg, last_try); } - public void update_from_encrypt_status(Entities.Message msg, EncryptState new_try) { + public void update_from_encrypt_status(Entities.Message msg, Xep.Omemo.EncryptState new_try) { this.msg = msg; this.last_try = new_try; this.waiting_other_sessions = new_try.other_unknown; @@ -59,10 +60,11 @@ public class Manager : StreamInteractionModule, Object { } } - private Manager(StreamInteractor stream_interactor, Database db, TrustManager trust_manager) { + private Manager(StreamInteractor stream_interactor, Database db, TrustManager trust_manager, HashMap encryptors) { this.stream_interactor = stream_interactor; this.db = db; this.trust_manager = trust_manager; + this.encryptors = encryptors; stream_interactor.stream_negotiated.connect(on_stream_negotiated); stream_interactor.get_module(MessageProcessor.IDENTITY).pre_message_send.connect(on_pre_message_send); @@ -125,7 +127,7 @@ public class Manager : StreamInteractionModule, Object { } //Attempt to encrypt the message - EncryptState enc_state = trust_manager.encrypt(message_stanza, conversation.account.bare_jid, recipients, stream, conversation.account); + Xep.Omemo.EncryptState enc_state = encryptors[conversation.account].encrypt(message_stanza, conversation.account.bare_jid, recipients, stream); MessageState state; lock (message_states) { if (message_states.has_key(message)) { @@ -411,8 +413,8 @@ public class Manager : StreamInteractionModule, Object { return true; // TODO wait for stream? } - public static void start(StreamInteractor stream_interactor, Database db, TrustManager trust_manager) { - Manager m = new Manager(stream_interactor, db, trust_manager); + public static void start(StreamInteractor stream_interactor, Database db, TrustManager trust_manager, HashMap encryptors) { + Manager m = new Manager(stream_interactor, db, trust_manager, encryptors); stream_interactor.add_module(m); } } diff --git a/plugins/omemo/src/logic/trust_manager.vala b/plugins/omemo/src/logic/trust_manager.vala index 1e61b201..20076a43 100644 --- a/plugins/omemo/src/logic/trust_manager.vala +++ b/plugins/omemo/src/logic/trust_manager.vala @@ -12,18 +12,15 @@ public class TrustManager { private StreamInteractor stream_interactor; private Database db; - private DecryptMessageListener decrypt_message_listener; private TagMessageListener tag_message_listener; - private HashMap message_device_id_map = new HashMap(Message.hash_func, Message.equals_func); + public HashMap message_device_id_map = new HashMap(Message.hash_func, Message.equals_func); public TrustManager(StreamInteractor stream_interactor, Database db) { this.stream_interactor = stream_interactor; this.db = db; - decrypt_message_listener = new DecryptMessageListener(stream_interactor, this, db, message_device_id_map); tag_message_listener = new TagMessageListener(stream_interactor, this, db, message_device_id_map); - stream_interactor.get_module(MessageProcessor.IDENTITY).received_pipeline.connect(decrypt_message_listener); stream_interactor.get_module(MessageProcessor.IDENTITY).received_pipeline.connect(tag_message_listener); } @@ -69,127 +66,6 @@ public class TrustManager { } } - private StanzaNode create_encrypted_key_node(uint8[] key, Address address, Store store) throws GLib.Error { - SessionCipher cipher = store.create_session_cipher(address); - CiphertextMessage device_key = cipher.encrypt(key); - debug("Created encrypted key for %s/%d", address.name, address.device_id); - 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; - } - - internal EncryptState encrypt_key(StanzaNode header_node, uint8[] keytag, Jid self_jid, Gee.List recipients, XmppStream stream, Account account) throws Error { - EncryptState status = new EncryptState(); - StreamModule module = stream.get_module(StreamModule.IDENTITY); - - //Check we have the bundles and device lists needed to send the message - 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++; - } - if (status.other_waiting_lists > 0) return status; - status.other_devices += get_trusted_devices(account, recipient).size; - } - if (status.own_devices == 0 || status.other_devices == 0) return status; - - - //Encrypt the key for each recipient's device individually - Address address = new Address("", 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_node(keytag, address, module.store); - header_node.put_node(key_node); - status.other_success++; - } catch (Error e) { - if (e.code == ErrorCode.UNKNOWN) status.other_unknown++; - else status.other_failure++; - } - } - } - - // Encrypt the key for each own device - 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_node(keytag, address, module.store); - header_node.put_node(key_node); - status.own_success++; - } catch (Error e) { - if (e.code == ErrorCode.UNKNOWN) status.own_unknown++; - else status.own_failure++; - } - } - } - - return status; - } - - public EncryptState encrypt(MessageStanza message, Jid self_jid, Gee.List recipients, XmppStream stream, Account account) { - const uint KEY_SIZE = 16; - const uint IV_SIZE = 12; - EncryptState status = new EncryptState(); - if (!Plugin.ensure_context()) return status; - if (message.to == null) return status; - - StreamModule module = stream.get_module(StreamModule.IDENTITY); - - try { - //Create a key and use it to encrypt the message - uint8[] key = new uint8[KEY_SIZE]; - Plugin.get_context().randomize(key); - uint8[] iv = new uint8[IV_SIZE]; - Plugin.get_context().randomize(iv); - - uint8[] aes_encrypt_result = aes_encrypt(Cipher.AES_GCM_NOPADDING, key, iv, message.body.data); - uint8[] ciphertext = aes_encrypt_result[0:aes_encrypt_result.length-16]; - uint8[] tag = aes_encrypt_result[aes_encrypt_result.length-16:aes_encrypt_result.length]; - uint8[] keytag = new uint8[key.length + tag.length]; - Memory.copy(keytag, key, key.length); - Memory.copy((uint8*)keytag + key.length, tag, tag.length); - - StanzaNode header_node; - StanzaNode encrypted_node = new StanzaNode.build("encrypted", NS_URI).add_self_xmlns() - .put_node(header_node = 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)))); - - status = encrypt_key(header_node, keytag, self_jid, recipients, stream, account); - - message.stanza.put_node(encrypted_node); - Xep.ExplicitEncryption.add_encryption_tag_to_message(message, NS_URI, "OMEMO"); - message.body = "[This message is OMEMO encrypted]"; - status.encrypted = true; - } catch (Error e) { - warning(@"Signal error while encrypting message: $(e.message)\n"); - message.body = "[OMEMO encryption failed]"; - status.encrypted = false; - } - return status; - } - public bool is_known_address(Account account, Jid jid) { int identity_id = db.identity.get_id(account.id); if (identity_id < 0) return false; @@ -260,182 +136,6 @@ public class TrustManager { return false; } } - - private class DecryptMessageListener : 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 TrustManager trust_manager; - private Database db; - private HashMap message_device_id_map; - - public DecryptMessageListener(StreamInteractor stream_interactor, TrustManager trust_manager, Database db, HashMap message_device_id_map) { - this.stream_interactor = stream_interactor; - this.trust_manager = trust_manager; - this.db = db; - this.message_device_id_map = message_device_id_map; - } - - public override async bool run(Entities.Message message, Xmpp.MessageStanza stanza, Conversation conversation) { - StreamModule module = stream_interactor.module_manager.get_module(conversation.account, StreamModule.IDENTITY); - Store store = module.store; - - StanzaNode? _encrypted = stanza.stanza.get_subnode("encrypted", NS_URI); - if (_encrypted == null || MessageFlag.get_flag(stanza) != null || stanza.from == null) return false; - StanzaNode encrypted = (!)_encrypted; - if (message.body == null && Xep.ExplicitEncryption.get_encryption_tag(stanza) == NS_URI) { - message.body = "[This message is OMEMO encrypted]"; // TODO temporary - }; - if (!Plugin.ensure_context()) return false; - int identity_id = db.identity.get_id(conversation.account.id); - MessageFlag flag = new MessageFlag(); - stanza.add_flag(flag); - StanzaNode? _header = encrypted.get_subnode("header"); - if (_header == null) return false; - StanzaNode header = (!)_header; - int sid = header.get_attribute_int("sid"); - if (sid <= 0) return false; - - var our_nodes = new ArrayList(); - foreach (StanzaNode key_node in header.get_subnodes("key")) { - debug("Is ours? %d =? %u", key_node.get_attribute_int("rid"), store.local_registration_id); - if (key_node.get_attribute_int("rid") == store.local_registration_id) { - our_nodes.add(key_node); - } - } - - string? payload = encrypted.get_deep_string_content("payload"); - string? iv_node = header.get_deep_string_content("iv"); - - foreach (StanzaNode key_node in our_nodes) { - string? key_node_content = key_node.get_string_content(); - if (payload == null || iv_node == null || key_node_content == null) continue; - uint8[] key; - uint8[] ciphertext = Base64.decode((!)payload); - uint8[] iv = Base64.decode((!)iv_node); - Gee.List possible_jids = new ArrayList(); - if (conversation.type_ == Conversation.Type.CHAT) { - possible_jids.add(stanza.from.bare_jid); - } else { - Jid? real_jid = message.real_jid; - if (real_jid != null) { - possible_jids.add(real_jid.bare_jid); - } else if (key_node.get_attribute_bool("prekey")) { - // pre key messages do store the identity key, so we can use that to find the real jid - PreKeySignalMessage msg = Plugin.get_context().deserialize_pre_key_signal_message(Base64.decode((!)key_node_content)); - string identity_key = Base64.encode(msg.identity_key.serialize()); - foreach (Row row in db.identity_meta.get_with_device_id(identity_id, sid).with(db.identity_meta.identity_key_public_base64, "=", identity_key)) { - try { - possible_jids.add(new Jid(row[db.identity_meta.address_name])); - } catch (InvalidJidError e) { - warning("Ignoring invalid jid from database: %s", e.message); - } - } - if (possible_jids.size != 1) { - continue; - } - } else { - // If we don't know the device name (MUC history w/o MAM), test decryption with all keys with fitting device id - foreach (Row row in db.identity_meta.get_with_device_id(identity_id, sid)) { - try { - possible_jids.add(new Jid(row[db.identity_meta.address_name])); - } catch (InvalidJidError e) { - warning("Ignoring invalid jid from database: %s", e.message); - } - } - } - } - - if (possible_jids.size == 0) { - debug("Received message from unknown entity with device id %d", sid); - } - - foreach (Jid possible_jid in possible_jids) { - try { - Address address = new Address(possible_jid.to_string(), sid); - if (key_node.get_attribute_bool("prekey")) { - Row? device = db.identity_meta.get_device(identity_id, possible_jid.to_string(), sid); - PreKeySignalMessage msg = Plugin.get_context().deserialize_pre_key_signal_message(Base64.decode((!)key_node_content)); - string identity_key = Base64.encode(msg.identity_key.serialize()); - if (device != null && device[db.identity_meta.identity_key_public_base64] != null) { - if (device[db.identity_meta.identity_key_public_base64] != identity_key) { - critical("Tried to use a different identity key for a known device id."); - continue; - } - } else { - debug("Learn new device from incoming message from %s/%d", possible_jid.to_string(), sid); - bool blind_trust = db.trust.get_blind_trust(identity_id, possible_jid.to_string(), true); - if (db.identity_meta.insert_device_session(identity_id, possible_jid.to_string(), sid, identity_key, blind_trust ? TrustLevel.TRUSTED : TrustLevel.UNKNOWN) < 0) { - critical("Failed learning a device."); - continue; - } - XmppStream? stream = stream_interactor.get_stream(conversation.account); - if (device == null && stream != null) { - module.request_user_devicelist.begin(stream, possible_jid); - } - } - debug("Starting new session for decryption with device from %s/%d", possible_jid.to_string(), sid); - SessionCipher cipher = store.create_session_cipher(address); - key = cipher.decrypt_pre_key_signal_message(msg); - // TODO: Finish session - } else { - debug("Continuing session for decryption with device from %s/%d", possible_jid.to_string(), sid); - SignalMessage msg = Plugin.get_context().deserialize_signal_message(Base64.decode((!)key_node_content)); - SessionCipher cipher = store.create_session_cipher(address); - key = cipher.decrypt_signal_message(msg); - } - //address.device_id = 0; // TODO: Hack to have address obj live longer - - if (key.length >= 32) { - int authtaglength = key.length - 16; - uint8[] new_ciphertext = new uint8[ciphertext.length + authtaglength]; - uint8[] new_key = new uint8[16]; - Memory.copy(new_ciphertext, ciphertext, ciphertext.length); - Memory.copy((uint8*)new_ciphertext + ciphertext.length, (uint8*)key + 16, authtaglength); - Memory.copy(new_key, key, 16); - ciphertext = new_ciphertext; - key = new_key; - } - - message.body = arr_to_str(aes_decrypt(Cipher.AES_GCM_NOPADDING, key, iv, ciphertext)); - message_device_id_map[message] = address.device_id; - message.encryption = Encryption.OMEMO; - flag.decrypted = true; - } catch (Error e) { - debug("Decrypting message from %s/%d failed: %s", possible_jid.to_string(), sid, e.message); - continue; - } - - // If we figured out which real jid a message comes from due to decryption working, save it - if (conversation.type_ == Conversation.Type.GROUPCHAT && message.real_jid == null) { - message.real_jid = possible_jid; - } - return false; - } - } - - if ( - payload != null && // Ratchet forwarding doesn't contain payload and might not include us, which is ok - our_nodes.size == 0 && // The message was not encrypted to us - module.store.local_registration_id != sid // Message from this device. Never encrypted to itself. - ) { - db.identity_meta.update_last_message_undecryptable(identity_id, sid, message.time); - trust_manager.bad_message_state_updated(conversation.account, message.from, sid); - } - - debug("Received OMEMO encryped message that could not be decrypted."); - return false; - } - - private string arr_to_str(uint8[] arr) { - // null-terminate the array - uint8[] rarr = new uint8[arr.length+1]; - Memory.copy(rarr, arr, arr.length); - return (string)rarr; - } - } } } -- cgit v1.2.3-54-g00ecf