package eu.siacs.conversations.crypto.axolotl; import android.support.annotation.NonNull; import android.support.annotation.Nullable; import android.util.Log; import org.whispersystems.libaxolotl.AxolotlAddress; import org.whispersystems.libaxolotl.DuplicateMessageException; import org.whispersystems.libaxolotl.InvalidKeyException; import org.whispersystems.libaxolotl.InvalidKeyIdException; import org.whispersystems.libaxolotl.InvalidMessageException; import org.whispersystems.libaxolotl.InvalidVersionException; import org.whispersystems.libaxolotl.LegacyMessageException; import org.whispersystems.libaxolotl.NoSessionException; import org.whispersystems.libaxolotl.SessionCipher; import org.whispersystems.libaxolotl.UntrustedIdentityException; import org.whispersystems.libaxolotl.protocol.CiphertextMessage; import org.whispersystems.libaxolotl.protocol.PreKeyWhisperMessage; import org.whispersystems.libaxolotl.protocol.WhisperMessage; import eu.siacs.conversations.Config; import eu.siacs.conversations.entities.Account; public class XmppAxolotlSession { private final SessionCipher cipher; private Integer preKeyId = null; private final SQLiteAxolotlStore sqLiteAxolotlStore; public AxolotlAddress getRemoteAddress() { return remoteAddress; } private final AxolotlAddress remoteAddress; private final Account account; private String fingerprint = null; public XmppAxolotlSession(Account account, SQLiteAxolotlStore store, AxolotlAddress remoteAddress, String fingerprint) { this(account, store, remoteAddress); this.fingerprint = fingerprint; } public XmppAxolotlSession(Account account, SQLiteAxolotlStore store, AxolotlAddress remoteAddress) { this.cipher = new SessionCipher(store, remoteAddress); this.remoteAddress = remoteAddress; this.sqLiteAxolotlStore = store; this.account = account; } public Integer getPreKeyId() { return preKeyId; } public void resetPreKeyId() { preKeyId = null; } public String getFingerprint() { return fingerprint; } protected void setTrust(SQLiteAxolotlStore.Trust trust) { sqLiteAxolotlStore.setFingerprintTrust(fingerprint, trust); } protected SQLiteAxolotlStore.Trust getTrust() { return sqLiteAxolotlStore.getFingerprintTrust(fingerprint); } @Nullable public byte[] processReceiving(XmppAxolotlMessage.XmppAxolotlMessageHeader incomingHeader) { byte[] plaintext = null; SQLiteAxolotlStore.Trust trust = getTrust(); switch (trust) { case INACTIVE: case UNDECIDED: case UNTRUSTED: case TRUSTED: try { try { PreKeyWhisperMessage message = new PreKeyWhisperMessage(incomingHeader.getContents()); Log.i(Config.LOGTAG, AxolotlService.getLogprefix(account) + "PreKeyWhisperMessage received, new session ID:" + message.getSignedPreKeyId() + "/" + message.getPreKeyId()); String fingerprint = message.getIdentityKey().getFingerprint().replaceAll("\\s", ""); if (this.fingerprint != null && !this.fingerprint.equals(fingerprint)) { Log.e(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Had session with fingerprint " + this.fingerprint + ", received message with fingerprint " + fingerprint); } else { this.fingerprint = fingerprint; plaintext = cipher.decrypt(message); if (message.getPreKeyId().isPresent()) { preKeyId = message.getPreKeyId().get(); } } } catch (InvalidMessageException | InvalidVersionException e) { Log.i(Config.LOGTAG, AxolotlService.getLogprefix(account) + "WhisperMessage received"); WhisperMessage message = new WhisperMessage(incomingHeader.getContents()); plaintext = cipher.decrypt(message); } catch (InvalidKeyException | InvalidKeyIdException | UntrustedIdentityException e) { Log.w(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Error decrypting axolotl header, " + e.getClass().getName() + ": " + e.getMessage()); } } catch (LegacyMessageException | InvalidMessageException | DuplicateMessageException | NoSessionException e) { Log.w(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Error decrypting axolotl header, " + e.getClass().getName() + ": " + e.getMessage()); } if (plaintext != null && trust == SQLiteAxolotlStore.Trust.INACTIVE) { setTrust(SQLiteAxolotlStore.Trust.TRUSTED); } break; case COMPROMISED: default: // ignore break; } return plaintext; } @Nullable public XmppAxolotlMessage.XmppAxolotlMessageHeader processSending(@NonNull byte[] outgoingMessage) { SQLiteAxolotlStore.Trust trust = getTrust(); if (trust == SQLiteAxolotlStore.Trust.TRUSTED) { CiphertextMessage ciphertextMessage = cipher.encrypt(outgoingMessage); XmppAxolotlMessage.XmppAxolotlMessageHeader header = new XmppAxolotlMessage.XmppAxolotlMessageHeader(remoteAddress.getDeviceId(), ciphertextMessage.serialize()); return header; } else { return null; } } }