private_recommendations/client.cpp

Go to the documentation of this file.

/*
SeComLib
Copyright 2012-2013 TU Delft, Information Security & Privacy Lab (http://isplab.tudelft.nl/)

Contributors:
Inald Lagendijk (R.L.Lagendijk@TUDelft.nl)
Mihai Todor (todormihai@gmail.com)
Thijs Veugen (P.J.M.Veugen@tudelft.nl)
Zekeriya Erkin (z.erkin@tudelft.nl)

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
#include "client.h"

namespace SeComLib {
namespace PrivateRecommendations {
    const std::string Client::configurationPath("PrivateRecommendations");

    Client::Client (const std::shared_ptr<ServiceProvider> &serviceProvider, const std::shared_ptr<PrivacyServiceProvider> &privacyServiceProvider, const PaillierPublicKey &publicKey) :
        serviceProvider(serviceProvider),
        privacyServiceProvider(privacyServiceProvider),
        paillierCryptoProvider(publicKey),
        blindingFactorCache(paillierCryptoProvider, BlindingFactorCacheParameters(configurationPath + ".BlindingFactorCache", Utils::Config::GetInstance().GetParameter<size_t>(configurationPath + ".l"))),
        userCount(Utils::Config::GetInstance().GetParameter<size_t>(configurationPath + ".userCount")) {
    }

    void Client::ComputeRecommendations () {
    #ifdef FIRST_USER_ONLY
        for (size_t user = 0; user < 1; ++user) {
    #else
        for (size_t user = 0; user < this->userCount; ++user) {
    #endif
            //measure the time it takes to decrypt the recommendations for each user
            Utils::CpuTimer recommendationsProcessingTimer;

            /*
            std::cout << "User " << user << ":" << std::endl << std::endl;
            */

            Paillier::Ciphertext encryptedL = this->serviceProvider->GetEncryptedL(user);
            ServiceProvider::EncryptedUserData encryptedURSum = this->serviceProvider->GetEncryptedURSum(user);

            const BlindingFactorContainer &LblindingFactor = this->blindingFactorCache.Pop();

            unsigned long L = (this->privacyServiceProvider->SecureDecryption(encryptedL + LblindingFactor.encryptedR) - LblindingFactor.r).ToUnsignedLong();

            /*
            std::cout << "L:" << L << std::endl;
            */
            if (L == 0) {
                std::cout << "No similar users found." << std::endl;
                continue;
            }

            std::vector<unsigned long> URSum;
            for (ServiceProvider::EncryptedUserData::iterator encryptedURSumIterator = encryptedURSum.begin(); encryptedURSumIterator != encryptedURSum.end(); ++encryptedURSumIterator) {
                const BlindingFactorContainer &URSumblindingFactor = this->blindingFactorCache.Pop();

                URSum.push_back((this->privacyServiceProvider->SecureDecryption(*encryptedURSumIterator + URSumblindingFactor.encryptedR) - URSumblindingFactor.r).ToUnsignedLong());
            }

            /*
            std::cout << "UR_sum:" << std::endl;
            for (std::vector<unsigned long>::const_iterator URSumIterator = URSum.begin(); URSumIterator != URSum.end(); ++URSumIterator) {
                std::cout << *URSumIterator << std::endl;
            }

            std::cout << "Recommendations:" << std::endl;
            for (std::vector<unsigned long>::const_iterator URSumIterator = URSum.begin(); URSumIterator != URSum.end(); ++URSumIterator) {
                std::cout << static_cast<double>(*URSumIterator) / static_cast<double>(L) << std::endl;
            }
            */

            std::cout << std::endl;

            std::cout << "Processed recommendations for user " << user << " in " << recommendationsProcessingTimer.ToString() << std::endl;
        }
    }

}//namespace PrivateRecommendations
}//namespace SeComLib