1*2abb3134SXin Li# Copyright 2014 Google Inc. All rights reserved. 2*2abb3134SXin Li# 3*2abb3134SXin Li# Licensed under the Apache License, Version 2.0 (the "License"); 4*2abb3134SXin Li# you may not use this file except in compliance with the License. 5*2abb3134SXin Li# You may obtain a copy of the License at 6*2abb3134SXin Li# 7*2abb3134SXin Li# http://www.apache.org/licenses/LICENSE-2.0 8*2abb3134SXin Li# 9*2abb3134SXin Li# Unless required by applicable law or agreed to in writing, software 10*2abb3134SXin Li# distributed under the License is distributed on an "AS IS" BASIS, 11*2abb3134SXin Li# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12*2abb3134SXin Li# See the License for the specific language governing permissions and 13*2abb3134SXin Li# limitations under the License. 14*2abb3134SXin Li 15*2abb3134SXin Li"""fastrand.py - Python wrapper for _fastrand.""" 16*2abb3134SXin Li 17*2abb3134SXin Li# NOTE: We could retire this module in favor of the C++ client? One reason to 18*2abb3134SXin Li# keep it is if it supports a wider range of params (e.g. more than 32 or 64 19*2abb3134SXin Li# bits.) 20*2abb3134SXin Li 21*2abb3134SXin Liimport random 22*2abb3134SXin Li 23*2abb3134SXin Liimport _fastrand 24*2abb3134SXin Li 25*2abb3134SXin Li 26*2abb3134SXin Liclass FastIrrRand(object): 27*2abb3134SXin Li """Fast insecure version of rappor.SecureIrrRand.""" 28*2abb3134SXin Li 29*2abb3134SXin Li def __init__(self, params): 30*2abb3134SXin Li randbits = _fastrand.randbits # accelerated function 31*2abb3134SXin Li num_bits = params.num_bloombits 32*2abb3134SXin Li 33*2abb3134SXin Li # IRR probabilities 34*2abb3134SXin Li self.p_gen = lambda: randbits(params.prob_p, num_bits) 35*2abb3134SXin Li self.q_gen = lambda: randbits(params.prob_q, num_bits) 36