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diff --git a/src/leap/soledad/client/_db/pragmas.py b/src/leap/soledad/client/_db/pragmas.py
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+++ b/src/leap/soledad/client/_db/pragmas.py
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+# -*- coding: utf-8 -*-
+# pragmas.py
+# Copyright (C) 2013, 2014 LEAP
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program. If not, see <http://www.gnu.org/licenses/>.
+"""
+Different pragmas used in the initialization of the SQLCipher database.
+"""
+import string
+import threading
+import os
+
+from leap.soledad.common import soledad_assert
+from leap.soledad.common.log import getLogger
+
+
+logger = getLogger(__name__)
+
+
+_db_init_lock = threading.Lock()
+
+
+def set_init_pragmas(conn, opts=None, extra_queries=None):
+    """
+    Set the initialization pragmas.
+
+    This includes the crypto pragmas, and any other options that must
+    be passed early to sqlcipher db.
+    """
+    soledad_assert(opts is not None)
+    extra_queries = [] if extra_queries is None else extra_queries
+    with _db_init_lock:
+        # only one execution path should initialize the db
+        _set_init_pragmas(conn, opts, extra_queries)
+
+
+def _set_init_pragmas(conn, opts, extra_queries):
+
+    sync_off = os.environ.get('LEAP_SQLITE_NOSYNC')
+    memstore = os.environ.get('LEAP_SQLITE_MEMSTORE')
+    nowal = os.environ.get('LEAP_SQLITE_NOWAL')
+
+    set_crypto_pragmas(conn, opts)
+
+    if not nowal:
+        set_write_ahead_logging(conn)
+    if sync_off:
+        set_synchronous_off(conn)
+    else:
+        set_synchronous_normal(conn)
+    if memstore:
+        set_mem_temp_store(conn)
+
+    for query in extra_queries:
+        conn.cursor().execute(query)
+
+
+def set_crypto_pragmas(db_handle, sqlcipher_opts):
+    """
+    Set cryptographic params (key, cipher, KDF number of iterations and
+    cipher page size).
+
+    :param db_handle:
+    :type db_handle:
+    :param sqlcipher_opts: options for the SQLCipherDatabase
+    :type sqlcipher_opts: SQLCipherOpts instance
+    """
+    # XXX assert CryptoOptions
+    opts = sqlcipher_opts
+    _set_key(db_handle, opts.key, opts.is_raw_key)
+    _set_cipher(db_handle, opts.cipher)
+    _set_kdf_iter(db_handle, opts.kdf_iter)
+    _set_cipher_page_size(db_handle, opts.cipher_page_size)
+
+
+def _set_key(db_handle, key, is_raw_key):
+    """
+    Set the ``key`` for use with the database.
+
+    The process of creating a new, encrypted database is called 'keying'
+    the database. SQLCipher uses just-in-time key derivation at the point
+    it is first needed for an operation. This means that the key (and any
+    options) must be set before the first operation on the database. As
+    soon as the database is touched (e.g. SELECT, CREATE TABLE, UPDATE,
+    etc.) and pages need to be read or written, the key is prepared for
+    use.
+
+    Implementation Notes:
+
+    * PRAGMA key should generally be called as the first operation on a
+        database.
+
+    :param key: The key for use with the database.
+    :type key: str
+    :param is_raw_key:
+        Whether C{key} is a raw 64-char hex string or a passphrase that should
+        be hashed to obtain the encyrption key.
+    :type is_raw_key: bool
+    """
+    if is_raw_key:
+        _set_key_raw(db_handle, key)
+    else:
+        _set_key_passphrase(db_handle, key)
+
+
+def _set_key_passphrase(db_handle, passphrase):
+    """
+    Set a passphrase for encryption key derivation.
+
+    The key itself can be a passphrase, which is converted to a key using
+    PBKDF2 key derivation. The result is used as the encryption key for
+    the database. By using this method, there is no way to alter the KDF;
+    if you want to do so you should use a raw key instead and derive the
+    key using your own KDF.
+
+    :param db_handle: A handle to the SQLCipher database.
+    :type db_handle: pysqlcipher.Connection
+    :param passphrase: The passphrase used to derive the encryption key.
+    :type passphrase: str
+    """
+    db_handle.cursor().execute("PRAGMA key = '%s'" % passphrase)
+
+
+def _set_key_raw(db_handle, key):
+    """
+    Set a raw hexadecimal encryption key.
+
+    It is possible to specify an exact byte sequence using a blob literal.
+    With this method, it is the calling application's responsibility to
+    ensure that the data provided is a 64 character hex string, which will
+    be converted directly to 32 bytes (256 bits) of key data.
+
+    :param db_handle: A handle to the SQLCipher database.
+    :type db_handle: pysqlcipher.Connection
+    :param key: A 64 character hex string.
+    :type key: str
+    """
+    if not all(c in string.hexdigits for c in key):
+        raise NotAnHexString(key)
+    db_handle.cursor().execute('PRAGMA key = "x\'%s"' % key)
+
+
+def _set_cipher(db_handle, cipher='aes-256-cbc'):
+    """
+    Set the cipher and mode to use for symmetric encryption.
+
+    SQLCipher uses aes-256-cbc as the default cipher and mode of
+    operation. It is possible to change this, though not generally
+    recommended, using PRAGMA cipher.
+
+    SQLCipher makes direct use of libssl, so all cipher options available
+    to libssl are also available for use with SQLCipher. See `man enc` for
+    OpenSSL's supported ciphers.
+
+    Implementation Notes:
+
+    * PRAGMA cipher must be called after PRAGMA key and before the first
+        actual database operation or it will have no effect.
+
+    * If a non-default value is used PRAGMA cipher to create a database,
+        it must also be called every time that database is opened.
+
+    * SQLCipher does not implement its own encryption. Instead it uses the
+        widely available and peer-reviewed OpenSSL libcrypto for all
+        cryptographic functions.
+
+    :param db_handle: A handle to the SQLCipher database.
+    :type db_handle: pysqlcipher.Connection
+    :param cipher: The cipher and mode to use.
+    :type cipher: str
+    """
+    db_handle.cursor().execute("PRAGMA cipher = '%s'" % cipher)
+
+
+def _set_kdf_iter(db_handle, kdf_iter=4000):
+    """
+    Set the number of iterations for the key derivation function.
+
+    SQLCipher uses PBKDF2 key derivation to strengthen the key and make it
+    resistent to brute force and dictionary attacks. The default
+    configuration uses 4000 PBKDF2 iterations (effectively 16,000 SHA1
+    operations). PRAGMA kdf_iter can be used to increase or decrease the
+    number of iterations used.
+
+    Implementation Notes:
+
+    * PRAGMA kdf_iter must be called after PRAGMA key and before the first
+        actual database operation or it will have no effect.
+
+    * If a non-default value is used PRAGMA kdf_iter to create a database,
+        it must also be called every time that database is opened.
+
+    * It is not recommended to reduce the number of iterations if a
+        passphrase is in use.
+
+    :param db_handle: A handle to the SQLCipher database.
+    :type db_handle: pysqlcipher.Connection
+    :param kdf_iter: The number of iterations to use.
+    :type kdf_iter: int
+    """
+    db_handle.cursor().execute("PRAGMA kdf_iter = '%d'" % kdf_iter)
+
+
+def _set_cipher_page_size(db_handle, cipher_page_size=1024):
+    """
+    Set the page size of the encrypted database.
+
+    SQLCipher 2 introduced the new PRAGMA cipher_page_size that can be
+    used to adjust the page size for the encrypted database. The default
+    page size is 1024 bytes, but it can be desirable for some applications
+    to use a larger page size for increased performance. For instance,
+    some recent testing shows that increasing the page size can noticeably
+    improve performance (5-30%) for certain queries that manipulate a
+    large number of pages (e.g. selects without an index, large inserts in
+    a transaction, big deletes).
+
+    To adjust the page size, call the pragma immediately after setting the
+    key for the first time and each subsequent time that you open the
+    database.
+
+    Implementation Notes:
+
+    * PRAGMA cipher_page_size must be called after PRAGMA key and before
+        the first actual database operation or it will have no effect.
+
+    * If a non-default value is used PRAGMA cipher_page_size to create a
+        database, it must also be called every time that database is opened.
+
+    :param db_handle: A handle to the SQLCipher database.
+    :type db_handle: pysqlcipher.Connection
+    :param cipher_page_size: The page size.
+    :type cipher_page_size: int
+    """
+    db_handle.cursor().execute(
+        "PRAGMA cipher_page_size = '%d'" % cipher_page_size)
+
+
+# XXX UNUSED ?
+def set_rekey(db_handle, new_key, is_raw_key):
+    """
+    Change the key of an existing encrypted database.
+
+    To change the key on an existing encrypted database, it must first be
+    unlocked with the current encryption key. Once the database is
+    readable and writeable, PRAGMA rekey can be used to re-encrypt every
+    page in the database with a new key.
+
+    * PRAGMA rekey must be called after PRAGMA key. It can be called at any
+        time once the database is readable.
+
+    * PRAGMA rekey can not be used to encrypted a standard SQLite
+        database! It is only useful for changing the key on an existing
+        database.
+
+    * Previous versions of SQLCipher provided a PRAGMA rekey_cipher and
+        code>PRAGMA rekey_kdf_iter. These are deprecated and should not be
+        used. Instead, use sqlcipher_export().
+
+    :param db_handle: A handle to the SQLCipher database.
+    :type db_handle: pysqlcipher.Connection
+    :param new_key: The new key.
+    :type new_key: str
+    :param is_raw_key: Whether C{password} is a raw 64-char hex string or a
+                    passphrase that should be hashed to obtain the encyrption
+                    key.
+    :type is_raw_key: bool
+    """
+    if is_raw_key:
+        _set_rekey_raw(db_handle, new_key)
+    else:
+        _set_rekey_passphrase(db_handle, new_key)
+
+
+def _set_rekey_passphrase(db_handle, passphrase):
+    """
+    Change the passphrase for encryption key derivation.
+
+    The key itself can be a passphrase, which is converted to a key using
+    PBKDF2 key derivation. The result is used as the encryption key for
+    the database.
+
+    :param db_handle: A handle to the SQLCipher database.
+    :type db_handle: pysqlcipher.Connection
+    :param passphrase: The passphrase used to derive the encryption key.
+    :type passphrase: str
+    """
+    db_handle.cursor().execute("PRAGMA rekey = '%s'" % passphrase)
+
+
+def _set_rekey_raw(db_handle, key):
+    """
+    Change the raw hexadecimal encryption key.
+
+    It is possible to specify an exact byte sequence using a blob literal.
+    With this method, it is the calling application's responsibility to
+    ensure that the data provided is a 64 character hex string, which will
+    be converted directly to 32 bytes (256 bits) of key data.
+
+    :param db_handle: A handle to the SQLCipher database.
+    :type db_handle: pysqlcipher.Connection
+    :param key: A 64 character hex string.
+    :type key: str
+    """
+    if not all(c in string.hexdigits for c in key):
+        raise NotAnHexString(key)
+    db_handle.cursor().execute('PRAGMA rekey = "x\'%s"' % key)
+
+
+def set_synchronous_off(db_handle):
+    """
+    Change the setting of the "synchronous" flag to OFF.
+    """
+    logger.debug("sqlcipher: setting synchronous off")
+    db_handle.cursor().execute('PRAGMA synchronous=OFF')
+
+
+def set_synchronous_normal(db_handle):
+    """
+    Change the setting of the "synchronous" flag to NORMAL.
+    """
+    logger.debug("sqlcipher: setting synchronous normal")
+    db_handle.cursor().execute('PRAGMA synchronous=NORMAL')
+
+
+def set_mem_temp_store(db_handle):
+    """
+    Use a in-memory store for temporary tables.
+    """
+    logger.debug("sqlcipher: setting temp_store memory")
+    db_handle.cursor().execute('PRAGMA temp_store=MEMORY')
+
+
+def set_write_ahead_logging(db_handle):
+    """
+    Enable write-ahead logging, and set the autocheckpoint to 50 pages.
+
+    Setting the autocheckpoint to a small value, we make the reads not
+    suffer too much performance degradation.
+
+    From the sqlite docs:
+
+    "There is a tradeoff between average read performance and average write
+    performance. To maximize the read performance, one wants to keep the
+    WAL as small as possible and hence run checkpoints frequently, perhaps
+    as often as every COMMIT. To maximize write performance, one wants to
+    amortize the cost of each checkpoint over as many writes as possible,
+    meaning that one wants to run checkpoints infrequently and let the WAL
+    grow as large as possible before each checkpoint. The decision of how
+    often to run checkpoints may therefore vary from one application to
+    another depending on the relative read and write performance
+    requirements of the application. The default strategy is to run a
+    checkpoint once the WAL reaches 1000 pages"
+    """
+    logger.debug("sqlcipher: setting write-ahead logging")
+    db_handle.cursor().execute('PRAGMA journal_mode=WAL')
+
+    # The optimum value can still use a little bit of tuning, but we favor
+    # small sizes of the WAL file to get fast reads, since we assume that
+    # the writes will be quick enough to not block too much.
+
+    db_handle.cursor().execute('PRAGMA wal_autocheckpoint=50')
+
+
+class NotAnHexString(Exception):
+    """
+    Raised when trying to (raw) key the database with a non-hex string.
+    """
+    pass