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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);
}
public void set_blind_trust(Account account, Jid jid, bool blind_trust) {
db.trust.update()
.with(db.trust.identity_id, "=", account.id)
.with(db.trust.address_name, "=", jid.bare_jid.to_string())
.set(db.trust.blind_trust, blind_trust);
}
public void set_device_trust(Account account, Jid jid, int device_id, Database.IdentityMetaTable.TrustLevel trust_level) {
db.identity_meta.update()
.with(db.identity_meta.identity_id, "=", account.id)
.with(db.identity_meta.address_name, "=", jid.bare_jid.to_string())
.with(db.identity_meta.device_id, "=", device_id)
.set(db.identity_meta.trust_level, trust_level).perform();
}
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 {
//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;
//Create a key and use it to encrypt the message
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))));
//Encrypt the key for each recipient's device individually
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.get_trusted_devices(account.id, jid.bare_jid.to_string())) {
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.get_device(conversation.account.id, jid.bare_jid.to_string(), header.get_attribute_int("sid"))[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;
}
}
}
}
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