import hashlib
import os
import binascii

__ROUNDS=100000

def gen_salt(size=16):
    return binascii.hexlify(os.urandom(size))

def encrypt_password(password,salt=None):
    salt=binascii.unhexlify(salt) if salt else ''
    return binascii.hexlify(hashlib.pbkdf2_hmac("sha512",password,salt,__ROUNDS))

def check_password(encrypted_password,clear_password,salt=None):
    salt=binascii.unhexlify(salt) if salt else ''
    return encrypted_password==binascii.hexlify(hashlib.pbkdf2_hmac("sha512",clear_password,salt,__ROUNDS))

def login_validation(auth,auth_value):
    #TBD
    return True