diff options
Diffstat (limited to 'client')
| -rw-r--r-- | client/changes/next-changelog.rst | 1 | ||||
| -rw-r--r-- | client/src/leap/soledad/client/secrets.py | 91 |
2 files changed, 79 insertions, 13 deletions
diff --git a/client/changes/next-changelog.rst b/client/changes/next-changelog.rst index cffe4954..7ddb3a57 100644 --- a/client/changes/next-changelog.rst +++ b/client/changes/next-changelog.rst @@ -10,6 +10,7 @@ I've added a new category `Misc` so we can track doc/style/packaging stuff. Features ~~~~~~~~ +- Add recovery document format version for future migrations. - Use DeferredLock instead of its locking cousin. - `#1234 <https://leap.se/code/issues/1234>`_: Description of the new feature corresponding with issue #1234. - New feature without related issue number. diff --git a/client/src/leap/soledad/client/secrets.py b/client/src/leap/soledad/client/secrets.py index 714b2dfe..c35b881e 100644 --- a/client/src/leap/soledad/client/secrets.py +++ b/client/src/leap/soledad/client/secrets.py @@ -143,6 +143,8 @@ class SoledadSecrets(object): KDF_LENGTH_KEY = 'kdf_length' KDF_SCRYPT = 'scrypt' CIPHER_AES256 = 'aes256' + RECOVERY_DOC_VERSION_KEY = 'version' + RECOVERY_DOC_VERSION = 1 """ Keys used to access storage secrets in recovery documents. """ @@ -192,9 +194,15 @@ class SoledadSecrets(object): # STAGE 1 - verify if secrets exist locally try: logger.info("Trying to load secrets from local storage...") - self._load_secrets_from_local_file() + version = self._load_secrets_from_local_file() + # eventually migrate local and remote stored documents from old + # format version + if version < self.RECOVERY_DOC_VERSION: + self._store_secrets() + self._upload_crypto_secrets() logger.info("Found secrets in local storage.") return + except NoStorageSecret: logger.info("Could not find secrets in local storage.") @@ -204,7 +212,12 @@ class SoledadSecrets(object): # server. try: logger.info('Trying to fetch secrets from remote storage...') - self._download_crypto_secrets() + version = self._download_crypto_secrets() + self._store_secrets() + # eventually migrate remote stored document from old format + # version + if version < self.RECOVERY_DOC_VERSION: + self._upload_crypto_secrets() logger.info('Found secrets in remote storage.') return except NoStorageSecret: @@ -240,6 +253,9 @@ class SoledadSecrets(object): def _load_secrets_from_local_file(self): """ Load storage secrets from local file. + + :return version: The version of the locally stored recovery document. + :raise NoStorageSecret: Raised if there are no secrets available in local storage. """ @@ -251,13 +267,18 @@ class SoledadSecrets(object): content = None with open(self._secrets_path, 'r') as f: content = json.loads(f.read()) - _, active_secret = self._import_recovery_document(content) + _, active_secret, version = self._import_recovery_document(content) + self._maybe_set_active_secret(active_secret) + return version + def _download_crypto_secrets(self): """ Download crypto secrets. + :return version: The version of the remotelly stored recovery document. + :raise NoStorageSecret: Raised if there are no secrets available in remote storage. """ @@ -268,9 +289,10 @@ class SoledadSecrets(object): if doc is None: raise NoStorageSecret - _, active_secret = self._import_recovery_document(doc.content) + _, active_secret, version = self._import_recovery_document(doc.content) self._maybe_set_active_secret(active_secret) - self._store_secrets() # save new secrets in local file + + return version def _gen_crypto_secrets(self): """ @@ -325,7 +347,7 @@ class SoledadSecrets(object): """ Export the storage secrets. - A recovery document has the following structure: + Current format of recovery document has the following structure: { 'storage_secrets': { @@ -336,6 +358,7 @@ class SoledadSecrets(object): }, }, 'active_secret': '<secret_id>', + 'version': '<recovery document format version>', } Note that multiple storage secrets might be stored in one recovery @@ -353,13 +376,14 @@ class SoledadSecrets(object): data = { self.STORAGE_SECRETS_KEY: encrypted_secrets, self.ACTIVE_SECRET_KEY: self._secret_id, + self.RECOVERY_DOC_VERSION_KEY: self.RECOVERY_DOC_VERSION, } return data def _import_recovery_document(self, data): """ - Import storage secrets for symmetric encryption and uuid (if present) - from a recovery document. + Import storage secrets for symmetric encryption from a recovery + document. Note that this method does not store the imported data on disk. For that, use C{self._store_secrets()}. @@ -367,11 +391,44 @@ class SoledadSecrets(object): :param data: The recovery document. :type data: dict - :return: A tuple containing the number of imported secrets and the - secret_id of the last active secret. - :rtype: (int, str) + :return: A tuple containing the number of imported secrets, the + secret_id of the last active secret, and the recovery + document format version. + :rtype: (int, str, int) """ soledad_assert(self.STORAGE_SECRETS_KEY in data) + version = data.get(self.RECOVERY_DOC_VERSION_KEY, 1) + meth = getattr(self, '_import_recovery_document_version_%d' % version) + secret_count, active_secret = meth(data) + return secret_count, active_secret, version + + def _import_recovery_document_version_1(self, data): + """ + Import storage secrets for symmetric encryption from a recovery + document with format version 1. + + Version 1 of recovery document has the following structure: + + { + 'storage_secrets': { + '<storage_secret id>': { + 'cipher': 'aes256', + 'length': <secret length>, + 'secret': '<encrypted storage_secret>', + }, + }, + 'active_secret': '<secret_id>', + 'version': '<recovery document format version>', + } + + :param data: The recovery document. + :type data: dict + + :return: A tuple containing the number of imported secrets, the + secret_id of the last active secret, and the recovery + document format version. + :rtype: (int, str, int) + """ # include secrets in the secret pool. secret_count = 0 secrets = data[self.STORAGE_SECRETS_KEY].items() @@ -384,7 +441,7 @@ class SoledadSecrets(object): if secret_id not in self._secrets: try: self._secrets[secret_id] = \ - self._decrypt_storage_secret(encrypted_secret) + self._decrypt_storage_secret_version_1(encrypted_secret) secret_count += 1 except SecretsException as e: logger.error("Failed to decrypt storage secret: %s" @@ -443,13 +500,21 @@ class SoledadSecrets(object): # Management of secret for symmetric encryption. # - def _decrypt_storage_secret(self, encrypted_secret_dict): + def _decrypt_storage_secret_version_1(self, encrypted_secret_dict): """ Decrypt the storage secret. Storage secret is encrypted before being stored. This method decrypts and returns the decrypted storage secret. + Version 1 of storage secret format has the following structure: + + '<storage_secret id>': { + 'cipher': 'aes256', + 'length': <secret length>, + 'secret': '<encrypted storage_secret>', + }, + :param encrypted_secret_dict: The encrypted storage secret. :type encrypted_secret_dict: dict |