Signal-Desktop/js/signal_protocol_store.js

(function() {
  'use strict';
  var TIMESTAMP_THRESHOLD = 5 * 1000; // 5 seconds
  var Direction = {
    SENDING: 1,
    RECEIVING: 2,
  };

  var VerifiedStatus = {
    DEFAULT: 0,
    VERIFIED: 1,
    UNVERIFIED: 2,
  };

  function validateVerifiedStatus(status) {
    if (
      status === VerifiedStatus.DEFAULT ||
      status === VerifiedStatus.VERIFIED ||
      status === VerifiedStatus.UNVERIFIED
    ) {
      return true;
    }
    return false;
  }

  var StaticByteBufferProto = new dcodeIO.ByteBuffer().__proto__;
  var StaticArrayBufferProto = new ArrayBuffer().__proto__;
  var StaticUint8ArrayProto = new Uint8Array().__proto__;

  function isStringable(thing) {
    return (
      thing === Object(thing) &&
      (thing.__proto__ == StaticArrayBufferProto ||
        thing.__proto__ == StaticUint8ArrayProto ||
        thing.__proto__ == StaticByteBufferProto)
    );
  }
  function convertToArrayBuffer(thing) {
    if (thing === undefined) {
      return undefined;
    }
    if (thing === Object(thing)) {
      if (thing.__proto__ == StaticArrayBufferProto) {
        return thing;
      }
      //TODO: Several more cases here...
    }

    if (thing instanceof Array) {
      // Assuming Uint16Array from curve25519
      var res = new ArrayBuffer(thing.length * 2);
      var uint = new Uint16Array(res);
      for (var i = 0; i < thing.length; i++) {
        uint[i] = thing[i];
      }
      return res;
    }

    var str;
    if (isStringable(thing)) {
      str = stringObject(thing);
    } else if (typeof thing == 'string') {
      str = thing;
    } else {
      throw new Error(
        'Tried to convert a non-stringable thing of type ' +
          typeof thing +
          ' to an array buffer'
      );
    }
    var res = new ArrayBuffer(str.length);
    var uint = new Uint8Array(res);
    for (var i = 0; i < str.length; i++) {
      uint[i] = str.charCodeAt(i);
    }
    return res;
  }

  function equalArrayBuffers(ab1, ab2) {
    if (!(ab1 instanceof ArrayBuffer && ab2 instanceof ArrayBuffer)) {
      return false;
    }
    if (ab1.byteLength !== ab2.byteLength) {
      return false;
    }
    var result = 0;
    var ta1 = new Uint8Array(ab1);
    var ta2 = new Uint8Array(ab2);
    for (var i = 0; i < ab1.byteLength; ++i) {
      result = result | (ta1[i] ^ ta2[i]);
    }
    return result === 0;
  }

  var Model = Backbone.Model.extend({ database: Whisper.Database });
  var PreKey = Model.extend({ storeName: 'preKeys' });
  var PreKeyCollection = Backbone.Collection.extend({
    storeName: 'preKeys',
    database: Whisper.Database,
    model: PreKey,
  });
  var SignedPreKey = Model.extend({ storeName: 'signedPreKeys' });
  var SignedPreKeyCollection = Backbone.Collection.extend({
    storeName: 'signedPreKeys',
    database: Whisper.Database,
    model: SignedPreKey,
  });
  var Session = Model.extend({ storeName: 'sessions' });
  var SessionCollection = Backbone.Collection.extend({
    storeName: 'sessions',
    database: Whisper.Database,
    model: Session,
    fetchSessionsForNumber: function(number) {
      return this.fetch({ range: [number + '.1', number + '.' + ':'] });
    },
  });
  var Unprocessed = Model.extend({ storeName: 'unprocessed' });
  var UnprocessedCollection = Backbone.Collection.extend({
    storeName: 'unprocessed',
    database: Whisper.Database,
    model: Unprocessed,
    comparator: 'timestamp',
  });
  var IdentityRecord = Model.extend({
    storeName: 'identityKeys',
    validAttributes: [
      'id',
      'publicKey',
      'firstUse',
      'timestamp',
      'verified',
      'nonblockingApproval',
    ],
    validate: function(attrs, options) {
      var attributeNames = _.keys(attrs);
      var validAttributes = this.validAttributes;
      var allValid = _.all(attributeNames, function(attributeName) {
        return _.contains(validAttributes, attributeName);
      });
      if (!allValid) {
        return new Error('Invalid identity key attribute names');
      }
      var allPresent = _.all(validAttributes, function(attributeName) {
        return _.contains(attributeNames, attributeName);
      });
      if (!allPresent) {
        return new Error('Missing identity key attributes');
      }

      if (typeof attrs.id !== 'string') {
        return new Error('Invalid identity key id');
      }
      if (!(attrs.publicKey instanceof ArrayBuffer)) {
        return new Error('Invalid identity key publicKey');
      }
      if (typeof attrs.firstUse !== 'boolean') {
        return new Error('Invalid identity key firstUse');
      }
      if (typeof attrs.timestamp !== 'number' || !(attrs.timestamp >= 0)) {
        return new Error('Invalid identity key timestamp');
      }
      if (!validateVerifiedStatus(attrs.verified)) {
        return new Error('Invalid identity key verified');
      }
      if (typeof attrs.nonblockingApproval !== 'boolean') {
        return new Error('Invalid identity key nonblockingApproval');
      }
    },
  });
  var Group = Model.extend({ storeName: 'groups' });
  var Item = Model.extend({ storeName: 'items' });

  function SignalProtocolStore() {}

  SignalProtocolStore.prototype = {
    constructor: SignalProtocolStore,
    getIdentityKeyPair: function() {
      var item = new Item({ id: 'identityKey' });
      return new Promise(function(resolve, reject) {
        item.fetch().then(function() {
          resolve(item.get('value'));
        }, reject);
      });
    },
    getLocalRegistrationId: function() {
      var item = new Item({ id: 'registrationId' });
      return new Promise(function(resolve, reject) {
        item.fetch().then(function() {
          resolve(item.get('value'));
        }, reject);
      });
    },

    /* Returns a prekeypair object or undefined */
    loadPreKey: function(keyId) {
      var prekey = new PreKey({ id: keyId });
      return new Promise(function(resolve) {
        prekey.fetch().then(
          function() {
            console.log('Successfully fetched prekey:', keyId);
            resolve({
              pubKey: prekey.get('publicKey'),
              privKey: prekey.get('privateKey'),
            });
          },
          function() {
            console.log('Failed to fetch prekey:', keyId);
            resolve();
          }
        );
      });
    },
    storePreKey: function(keyId, keyPair) {
      var prekey = new PreKey({
        id: keyId,
        publicKey: keyPair.pubKey,
        privateKey: keyPair.privKey,
      });
      return new Promise(function(resolve) {
        prekey.save().always(function() {
          resolve();
        });
      });
    },
    removePreKey: function(keyId) {
      var prekey = new PreKey({ id: keyId });

      this.trigger('removePreKey');

      return new Promise(function(resolve) {
        var deferred = prekey.destroy();
        if (!deferred) {
          return resolve();
        }

        return deferred.then(resolve, function(error) {
          console.log(
            'removePreKey error:',
            error && error.stack ? error.stack : error
          );
          resolve();
        });
      });
    },
    clearPreKeyStore: function() {
      return new Promise(function(resolve) {
        var preKeys = new PreKeyCollection();
        preKeys.sync('delete', preKeys, {}).always(resolve);
      });
    },

    /* Returns a signed keypair object or undefined */
    loadSignedPreKey: function(keyId) {
      var prekey = new SignedPreKey({ id: keyId });
      return new Promise(function(resolve) {
        prekey
          .fetch()
          .then(function() {
            console.log(
              'Successfully fetched signed prekey:',
              prekey.get('id')
            );
            resolve({
              pubKey: prekey.get('publicKey'),
              privKey: prekey.get('privateKey'),
              created_at: prekey.get('created_at'),
              keyId: prekey.get('id'),
              confirmed: prekey.get('confirmed'),
            });
          })
          .fail(function() {
            console.log('Failed to fetch signed prekey:', keyId);
            resolve();
          });
      });
    },
    loadSignedPreKeys: function() {
      if (arguments.length > 0) {
        return Promise.reject(
          new Error('loadSignedPreKeys takes no arguments')
        );
      }
      var signedPreKeys = new SignedPreKeyCollection();
      return new Promise(function(resolve) {
        signedPreKeys.fetch().then(function() {
          resolve(
            signedPreKeys.map(function(prekey) {
              return {
                pubKey: prekey.get('publicKey'),
                privKey: prekey.get('privateKey'),
                created_at: prekey.get('created_at'),
                keyId: prekey.get('id'),
                confirmed: prekey.get('confirmed'),
              };
            })
          );
        });
      });
    },
    storeSignedPreKey: function(keyId, keyPair, confirmed) {
      var prekey = new SignedPreKey({
        id: keyId,
        publicKey: keyPair.pubKey,
        privateKey: keyPair.privKey,
        created_at: Date.now(),
        confirmed: Boolean(confirmed),
      });
      return new Promise(function(resolve) {
        prekey.save().always(function() {
          resolve();
        });
      });
    },
    removeSignedPreKey: function(keyId) {
      var prekey = new SignedPreKey({ id: keyId });
      return new Promise(function(resolve, reject) {
        var deferred = prekey.destroy();
        if (!deferred) {
          return resolve();
        }

        deferred.then(resolve, reject);
      });
    },
    clearSignedPreKeysStore: function() {
      return new Promise(function(resolve) {
        var signedPreKeys = new SignedPreKeyCollection();
        signedPreKeys.sync('delete', signedPreKeys, {}).always(resolve);
      });
    },

    loadSession: function(encodedNumber) {
      if (encodedNumber === null || encodedNumber === undefined) {
        throw new Error('Tried to get session for undefined/null number');
      }
      return new Promise(function(resolve) {
        var session = new Session({ id: encodedNumber });
        session.fetch().always(function() {
          resolve(session.get('record'));
        });
      });
    },
    storeSession: function(encodedNumber, record) {
      if (encodedNumber === null || encodedNumber === undefined) {
        throw new Error('Tried to put session for undefined/null number');
      }
      return new Promise(function(resolve) {
        var number = textsecure.utils.unencodeNumber(encodedNumber)[0];
        var deviceId = parseInt(
          textsecure.utils.unencodeNumber(encodedNumber)[1]
        );

        var session = new Session({ id: encodedNumber });
        session.fetch().always(function() {
          session
            .save({
              record: record,
              deviceId: deviceId,
              number: number,
            })
            .fail(function(e) {
              console.log('Failed to save session', encodedNumber, e);
            })
            .always(function() {
              resolve();
            });
        });
      });
    },
    getDeviceIds: function(number) {
      if (number === null || number === undefined) {
        throw new Error('Tried to get device ids for undefined/null number');
      }
      return new Promise(function(resolve) {
        var sessions = new SessionCollection();
        sessions.fetchSessionsForNumber(number).always(function() {
          resolve(sessions.pluck('deviceId'));
        });
      });
    },
    removeSession: function(encodedNumber) {
      console.log('deleting session for ', encodedNumber);
      return new Promise(function(resolve) {
        var session = new Session({ id: encodedNumber });
        session
          .fetch()
          .then(function() {
            session.destroy().then(resolve);
          })
          .fail(resolve);
      });
    },
    removeAllSessions: function(number) {
      if (number === null || number === undefined) {
        throw new Error('Tried to remove sessions for undefined/null number');
      }
      return new Promise(function(resolve, reject) {
        var sessions = new SessionCollection();
        sessions.fetchSessionsForNumber(number).always(function() {
          var promises = [];
          while (sessions.length > 0) {
            promises.push(
              new Promise(function(res, rej) {
                sessions
                  .pop()
                  .destroy()
                  .then(res, rej);
              })
            );
          }
          Promise.all(promises).then(resolve, reject);
        });
      });
    },
    archiveSiblingSessions: function(identifier) {
      var address = libsignal.SignalProtocolAddress.fromString(identifier);
      return this.getDeviceIds(address.getName()).then(function(deviceIds) {
        var deviceIds = _.without(deviceIds, address.getDeviceId());
        return Promise.all(
          deviceIds.map(function(deviceId) {
            var sibling = new libsignal.SignalProtocolAddress(
              address.getName(),
              deviceId
            );
            console.log('closing session for', sibling.toString());
            var sessionCipher = new libsignal.SessionCipher(
              textsecure.storage.protocol,
              sibling
            );
            return sessionCipher.closeOpenSessionForDevice();
          })
        );
      });
    },
    archiveAllSessions: function(number) {
      return this.getDeviceIds(number).then(function(deviceIds) {
        return Promise.all(
          deviceIds.map(function(deviceId) {
            var address = new libsignal.SignalProtocolAddress(number, deviceId);
            console.log('closing session for', address.toString());
            var sessionCipher = new libsignal.SessionCipher(
              textsecure.storage.protocol,
              address
            );
            return sessionCipher.closeOpenSessionForDevice();
          })
        );
      });
    },
    clearSessionStore: function() {
      return new Promise(function(resolve) {
        var sessions = new SessionCollection();
        sessions.sync('delete', sessions, {}).always(resolve);
      });
    },
    isTrustedIdentity: function(identifier, publicKey, direction) {
      if (identifier === null || identifier === undefined) {
        throw new Error('Tried to get identity key for undefined/null key');
      }
      var number = textsecure.utils.unencodeNumber(identifier)[0];
      var isOurNumber = number === textsecure.storage.user.getNumber();
      var identityRecord = new IdentityRecord({ id: number });
      return new Promise(function(resolve) {
        identityRecord.fetch().always(resolve);
      }).then(
        function() {
          var existing = identityRecord.get('publicKey');

          if (isOurNumber) {
            return equalArrayBuffers(existing, publicKey);
          }

          switch (direction) {
            case Direction.SENDING:
              return this.isTrustedForSending(publicKey, identityRecord);
            case Direction.RECEIVING:
              return true;
            default:
              throw new Error('Unknown direction: ' + direction);
          }
        }.bind(this)
      );
    },
    isTrustedForSending: function(publicKey, identityRecord) {
      var existing = identityRecord.get('publicKey');

      if (!existing) {
        console.log('isTrustedForSending: Nothing here, returning true...');
        return true;
      }
      if (!equalArrayBuffers(existing, publicKey)) {
        console.log("isTrustedForSending: Identity keys don't match...");
        return false;
      }
      if (identityRecord.get('verified') === VerifiedStatus.UNVERIFIED) {
        console.log('Needs unverified approval!');
        return false;
      }
      if (this.isNonBlockingApprovalRequired(identityRecord)) {
        console.log('isTrustedForSending: Needs non-blocking approval!');
        return false;
      }

      return true;
    },
    loadIdentityKey: function(identifier) {
      if (identifier === null || identifier === undefined) {
        throw new Error('Tried to get identity key for undefined/null key');
      }
      var number = textsecure.utils.unencodeNumber(identifier)[0];
      return new Promise(function(resolve) {
        var identityRecord = new IdentityRecord({ id: number });
        identityRecord.fetch().always(function() {
          resolve(identityRecord.get('publicKey'));
        });
      });
    },
    saveIdentity: function(identifier, publicKey, nonblockingApproval) {
      if (identifier === null || identifier === undefined) {
        throw new Error('Tried to put identity key for undefined/null key');
      }
      if (!(publicKey instanceof ArrayBuffer)) {
        publicKey = convertToArrayBuffer(publicKey);
      }
      if (typeof nonblockingApproval !== 'boolean') {
        nonblockingApproval = false;
      }
      var number = textsecure.utils.unencodeNumber(identifier)[0];
      return new Promise(
        function(resolve, reject) {
          var identityRecord = new IdentityRecord({ id: number });
          identityRecord.fetch().always(
            function() {
              var oldpublicKey = identityRecord.get('publicKey');
              if (!oldpublicKey) {
                // Lookup failed, or the current key was removed, so save this one.
                console.log('Saving new identity...');
                identityRecord
                  .save({
                    publicKey: publicKey,
                    firstUse: true,
                    timestamp: Date.now(),
                    verified: VerifiedStatus.DEFAULT,
                    nonblockingApproval: nonblockingApproval,
                  })
                  .then(function() {
                    resolve(false);
                  }, reject);
              } else if (!equalArrayBuffers(oldpublicKey, publicKey)) {
                console.log('Replacing existing identity...');
                var previousStatus = identityRecord.get('verified');
                var verifiedStatus;
                if (
                  previousStatus === VerifiedStatus.VERIFIED ||
                  previousStatus === VerifiedStatus.UNVERIFIED
                ) {
                  verifiedStatus = VerifiedStatus.UNVERIFIED;
                } else {
                  verifiedStatus = VerifiedStatus.DEFAULT;
                }
                identityRecord
                  .save({
                    publicKey: publicKey,
                    firstUse: false,
                    timestamp: Date.now(),
                    verified: verifiedStatus,
                    nonblockingApproval: nonblockingApproval,
                  })
                  .then(
                    function() {
                      this.trigger('keychange', number);
                      this.archiveSiblingSessions(identifier).then(function() {
                        resolve(true);
                      }, reject);
                    }.bind(this),
                    reject
                  );
              } else if (this.isNonBlockingApprovalRequired(identityRecord)) {
                console.log('Setting approval status...');
                identityRecord
                  .save({
                    nonblockingApproval: nonblockingApproval,
                  })
                  .then(function() {
                    resolve(false);
                  }, reject);
              } else {
                resolve(false);
              }
            }.bind(this)
          );
        }.bind(this)
      );
    },
    isNonBlockingApprovalRequired: function(identityRecord) {
      return (
        !identityRecord.get('firstUse') &&
        Date.now() - identityRecord.get('timestamp') < TIMESTAMP_THRESHOLD &&
        !identityRecord.get('nonblockingApproval')
      );
    },
    saveIdentityWithAttributes: function(identifier, attributes) {
      if (identifier === null || identifier === undefined) {
        throw new Error('Tried to put identity key for undefined/null key');
      }
      var number = textsecure.utils.unencodeNumber(identifier)[0];
      return new Promise(function(resolve, reject) {
        var identityRecord = new IdentityRecord({ id: number });
        identityRecord.set(attributes);
        if (identityRecord.isValid()) {
          // false if invalid attributes
          identityRecord.save().then(resolve);
        } else {
          reject(identityRecord.validationError);
        }
      });
    },
    setApproval: function(identifier, nonblockingApproval) {
      if (identifier === null || identifier === undefined) {
        throw new Error('Tried to set approval for undefined/null identifier');
      }
      if (typeof nonblockingApproval !== 'boolean') {
        throw new Error('Invalid approval status');
      }
      var number = textsecure.utils.unencodeNumber(identifier)[0];
      return new Promise(function(resolve, reject) {
        var identityRecord = new IdentityRecord({ id: number });
        identityRecord.fetch().then(function() {
          identityRecord
            .save({
              nonblockingApproval: nonblockingApproval,
            })
            .then(
              function() {
                resolve();
              },
              function() {
                // catch
                reject(new Error('No identity record for ' + number));
              }
            );
        });
      });
    },
    setVerified: function(identifier, verifiedStatus, publicKey) {
      if (identifier === null || identifier === undefined) {
        throw new Error('Tried to set verified for undefined/null key');
      }
      if (!validateVerifiedStatus(verifiedStatus)) {
        throw new Error('Invalid verified status');
      }
      if (arguments.length > 2 && !(publicKey instanceof ArrayBuffer)) {
        throw new Error('Invalid public key');
      }
      return new Promise(function(resolve, reject) {
        var identityRecord = new IdentityRecord({ id: identifier });
        identityRecord.fetch().then(
          function() {
            if (
              !publicKey ||
              equalArrayBuffers(identityRecord.get('publicKey'), publicKey)
            ) {
              identityRecord.set({ verified: verifiedStatus });

              if (identityRecord.isValid()) {
                identityRecord.save({}).then(function() {
                  resolve();
                }, reject);
              } else {
                reject(identityRecord.validationError);
              }
            } else {
              console.log('No identity record for specified publicKey');
              resolve();
            }
          },
          function() {
            // catch
            reject(new Error('No identity record for ' + identifier));
          }
        );
      });
    },
    getVerified: function(identifier) {
      if (identifier === null || identifier === undefined) {
        throw new Error('Tried to set verified for undefined/null key');
      }
      return new Promise(function(resolve, reject) {
        var identityRecord = new IdentityRecord({ id: identifier });
        identityRecord.fetch().then(
          function() {
            var verifiedStatus = identityRecord.get('verified');
            if (validateVerifiedStatus(verifiedStatus)) {
              resolve(verifiedStatus);
            } else {
              resolve(VerifiedStatus.DEFAULT);
            }
          },
          function() {
            // catch
            reject(new Error('No identity record for ' + identifier));
          }
        );
      });
    },
    // Resolves to true if a new identity key was saved
    processContactSyncVerificationState: function(
      identifier,
      verifiedStatus,
      publicKey
    ) {
      if (verifiedStatus === VerifiedStatus.UNVERIFIED) {
        return this.processUnverifiedMessage(
          identifier,
          verifiedStatus,
          publicKey
        );
      } else {
        return this.processVerifiedMessage(
          identifier,
          verifiedStatus,
          publicKey
        );
      }
    },
    // This function encapsulates the non-Java behavior, since the mobile apps don't
    //   currently receive contact syncs and therefore will see a verify sync with
    //   UNVERIFIED status
    processUnverifiedMessage: function(identifier, verifiedStatus, publicKey) {
      if (identifier === null || identifier === undefined) {
        throw new Error('Tried to set verified for undefined/null key');
      }
      if (publicKey !== undefined && !(publicKey instanceof ArrayBuffer)) {
        throw new Error('Invalid public key');
      }
      return new Promise(
        function(resolve, reject) {
          var identityRecord = new IdentityRecord({ id: identifier });
          var isPresent = false;
          var isEqual = false;
          identityRecord
            .fetch()
            .then(function() {
              isPresent = true;
              if (publicKey) {
                isEqual = equalArrayBuffers(
                  publicKey,
                  identityRecord.get('publicKey')
                );
              }
            })
            .always(
              function() {
                if (
                  isPresent &&
                  isEqual &&
                  identityRecord.get('verified') !== VerifiedStatus.UNVERIFIED
                ) {
                  return textsecure.storage.protocol
                    .setVerified(identifier, verifiedStatus, publicKey)
                    .then(resolve, reject);
                }

                if (!isPresent || !isEqual) {
                  return textsecure.storage.protocol
                    .saveIdentityWithAttributes(identifier, {
                      publicKey: publicKey,
                      verified: verifiedStatus,
                      firstUse: false,
                      timestamp: Date.now(),
                      nonblockingApproval: true,
                    })
                    .then(
                      function() {
                        if (isPresent && !isEqual) {
                          this.trigger('keychange', identifier);
                          return this.archiveAllSessions(identifier).then(
                            function() {
                              // true signifies that we overwrote a previous key with a new one
                              return resolve(true);
                            },
                            reject
                          );
                        }

                        return resolve();
                      }.bind(this),
                      reject
                    );
                }

                // The situation which could get us here is:
                //   1. had a previous key
                //   2. new key is the same
                //   3. desired new status is same as what we had before
                return resolve();
              }.bind(this)
            );
        }.bind(this)
      );
    },
    // This matches the Java method as of
    //   https://github.com/signalapp/Signal-Android/blob/d0bb68e1378f689e4d10ac6a46014164992ca4e4/src/org/thoughtcrime/securesms/util/IdentityUtil.java#L188
    processVerifiedMessage: function(identifier, verifiedStatus, publicKey) {
      if (identifier === null || identifier === undefined) {
        throw new Error('Tried to set verified for undefined/null key');
      }
      if (!validateVerifiedStatus(verifiedStatus)) {
        throw new Error('Invalid verified status');
      }
      if (publicKey !== undefined && !(publicKey instanceof ArrayBuffer)) {
        throw new Error('Invalid public key');
      }
      return new Promise(
        function(resolve, reject) {
          var identityRecord = new IdentityRecord({ id: identifier });
          var isPresent = false;
          var isEqual = false;
          identityRecord
            .fetch()
            .then(function() {
              isPresent = true;
              if (publicKey) {
                isEqual = equalArrayBuffers(
                  publicKey,
                  identityRecord.get('publicKey')
                );
              }
            })
            .always(
              function() {
                if (!isPresent && verifiedStatus === VerifiedStatus.DEFAULT) {
                  console.log('No existing record for default status');
                  return resolve();
                }

                if (
                  isPresent &&
                  isEqual &&
                  identityRecord.get('verified') !== VerifiedStatus.DEFAULT &&
                  verifiedStatus === VerifiedStatus.DEFAULT
                ) {
                  return textsecure.storage.protocol
                    .setVerified(identifier, verifiedStatus, publicKey)
                    .then(resolve, reject);
                }

                if (
                  verifiedStatus === VerifiedStatus.VERIFIED &&
                  (!isPresent ||
                    (isPresent && !isEqual) ||
                    (isPresent &&
                      identityRecord.get('verified') !==
                        VerifiedStatus.VERIFIED))
                ) {
                  return textsecure.storage.protocol
                    .saveIdentityWithAttributes(identifier, {
                      publicKey: publicKey,
                      verified: verifiedStatus,
                      firstUse: false,
                      timestamp: Date.now(),
                      nonblockingApproval: true,
                    })
                    .then(
                      function() {
                        if (isPresent && !isEqual) {
                          this.trigger('keychange', identifier);
                          return this.archiveAllSessions(identifier).then(
                            function() {
                              // true signifies that we overwrote a previous key with a new one
                              return resolve(true);
                            },
                            reject
                          );
                        }

                        return resolve();
                      }.bind(this),
                      reject
                    );
                }

                // We get here if we got a new key and the status is DEFAULT. If the
                //   message is out of date, we don't want to lose whatever more-secure
                //   state we had before.
                return resolve();
              }.bind(this)
            );
        }.bind(this)
      );
    },
    isUntrusted: function(identifier) {
      if (identifier === null || identifier === undefined) {
        throw new Error('Tried to set verified for undefined/null key');
      }
      return new Promise(function(resolve, reject) {
        var identityRecord = new IdentityRecord({ id: identifier });
        identityRecord.fetch().then(
          function() {
            if (
              Date.now() - identityRecord.get('timestamp') <
                TIMESTAMP_THRESHOLD &&
              !identityRecord.get('nonblockingApproval') &&
              !identityRecord.get('firstUse')
            ) {
              resolve(true);
            } else {
              resolve(false);
            }
          },
          function() {
            // catch
            reject(new Error('No identity record for ' + identifier));
          }
        );
      });
    },
    removeIdentityKey: async function(number) {
      const identityRecord = new IdentityRecord({ id: number });
      try {
        await wrapDeferred(identityRecord.fetch());
        await wrapDeferred(identityRecord.destroy());
        return textsecure.storage.protocol.removeAllSessions(number);
      } catch (error) {
        throw new Error('Tried to remove identity for unknown number');
      }
    },

    // Groups
    getGroup: function(groupId) {
      if (groupId === null || groupId === undefined) {
        throw new Error('Tried to get group for undefined/null id');
      }
      return new Promise(function(resolve) {
        var group = new Group({ id: groupId });
        group.fetch().always(function() {
          resolve(group.get('data'));
        });
      });
    },
    putGroup: function(groupId, group) {
      if (groupId === null || groupId === undefined) {
        throw new Error('Tried to put group key for undefined/null id');
      }
      if (group === null || group === undefined) {
        throw new Error('Tried to put undefined/null group object');
      }
      var group = new Group({ id: groupId, data: group });
      return new Promise(function(resolve) {
        group.save().always(resolve);
      });
    },
    removeGroup: function(groupId) {
      if (groupId === null || groupId === undefined) {
        throw new Error('Tried to remove group key for undefined/null id');
      }
      return new Promise(function(resolve) {
        var group = new Group({ id: groupId });
        group.destroy().always(resolve);
      });
    },

    // Not yet processed messages - for resiliency
    getAllUnprocessed: function() {
      var collection;
      return new Promise(function(resolve, reject) {
        collection = new UnprocessedCollection();
        return collection.fetch().then(resolve, reject);
      }).then(function() {
        // Return a plain array of plain objects
        return collection.map(model => model.attributes);
      });
    },
    addUnprocessed: function(data) {
      return new Promise(function(resolve, reject) {
        var unprocessed = new Unprocessed(data);
        return unprocessed.save().then(resolve, reject);
      });
    },
    updateUnprocessed: function(id, updates) {
      return new Promise(
        function(resolve, reject) {
          var unprocessed = new Unprocessed({
            id: id,
          });
          return unprocessed.fetch().then(function() {
            return unprocessed.save(updates).then(resolve, reject);
          }, reject);
        }.bind(this)
      );
    },
    removeUnprocessed: function(id) {
      return new Promise(
        function(resolve, reject) {
          var unprocessed = new Unprocessed({
            id: id,
          });
          return unprocessed.destroy().then(resolve, reject);
        }.bind(this)
      );
    },
    removeAllData: function() {
      // First the in-memory caches:
      window.storage.reset(); // items store
      ConversationController.reset(); // conversations store

      // Then, the entire database:
      return Whisper.Database.clear();
    },
    removeAllConfiguration: function() {
      // First the in-memory cache for the items store:
      window.storage.reset();

      // Then anything in the database that isn't a message/conversation/group:
      return Whisper.Database.clearStores([
        'items',
        'identityKeys',
        'sessions',
        'signedPreKeys',
        'preKeys',
        'unprocessed',
      ]);
    },
  };
  _.extend(SignalProtocolStore.prototype, Backbone.Events);

  window.SignalProtocolStore = SignalProtocolStore;
  window.SignalProtocolStore.prototype.Direction = Direction;
  window.SignalProtocolStore.prototype.VerifiedStatus = VerifiedStatus;
})();