Function db_connect

Scripts/ButSystem.py:650–663

db_connect. Database helper for connecting to or initializing the SQLite database. This docstring was expanded to make future maintenance easier. Returns: Varies.

()

"""
    with open(src_path, "rb") as f:
        hdr = f.read(HDR_LEN)
        if len(hdr) != HDR_LEN or hdr[:len(MAGIC)] != MAGIC:
            raise ValueError("Not an encrypted ButSystem blob.")
        nonce = hdr[len(MAGIC):len(MAGIC)+NONCE_LEN]
        tag = hdr[len(MAGIC)+NONCE_LEN:HDR_LEN]

        cipher = Cipher(algorithms.AES(MASTER_KEY), modes.GCM(nonce, tag))
        decryptor = cipher.decryptor()

        while True:
            chunk = f.read(CHUNK)
            if not chunk:
                break
            out = decryptor.update(chunk)
            if out:
                yield out
        out = decryptor.finalize()