forked from openfheorg/openfhe-development
-
Notifications
You must be signed in to change notification settings - Fork 0
/
function-evaluation.cpp
174 lines (145 loc) · 7.09 KB
/
function-evaluation.cpp
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
//==================================================================================
// BSD 2-Clause License
//
// Copyright (c) 2014-2022, NJIT, Duality Technologies Inc. and other contributors
//
// All rights reserved.
//
// Author TPOC: contact@openfhe.org
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
// 1. Redistributions of source code must retain the above copyright notice, this
// list of conditions and the following disclaimer.
//
// 2. Redistributions in binary form must reproduce the above copyright notice,
// this list of conditions and the following disclaimer in the documentation
// and/or other materials provided with the distribution.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
// CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
// OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//==================================================================================
/*
Example of evaluating arbitrary smooth functions with the Chebyshev approximation using CKKS.
*/
#include "openfhe.h"
using namespace lbcrypto;
void EvalLogisticExample();
void EvalFunctionExample();
int main(int argc, char* argv[]) {
EvalLogisticExample();
EvalFunctionExample();
return 0;
}
// In this example, we evaluate the logistic function 1 / (1 + exp(-x)) on an input of doubles
void EvalLogisticExample() {
std::cout << "--------------------------------- EVAL LOGISTIC FUNCTION ---------------------------------"
<< std::endl;
CCParams<CryptoContextCKKSRNS> parameters;
// We set a smaller ring dimension to improve performance for this example.
// In production environments, the security level should be set to
// HEStd_128_classic, HEStd_192_classic, or HEStd_256_classic for 128-bit, 192-bit,
// or 256-bit security, respectively.
parameters.SetSecurityLevel(HEStd_NotSet);
parameters.SetRingDim(1 << 10);
#if NATIVEINT == 128
usint scalingModSize = 78;
usint firstModSize = 89;
#else
usint scalingModSize = 50;
usint firstModSize = 60;
#endif
parameters.SetScalingModSize(scalingModSize);
parameters.SetFirstModSize(firstModSize);
// Choosing a higher degree yields better precision, but a longer runtime.
uint32_t polyDegree = 16;
// The multiplicative depth depends on the polynomial degree.
// See the FUNCTION_EVALUATION.md file for a table mapping polynomial degrees to multiplicative depths.
uint32_t multDepth = 6;
parameters.SetMultiplicativeDepth(multDepth);
CryptoContext<DCRTPoly> cc = GenCryptoContext(parameters);
cc->Enable(PKE);
cc->Enable(KEYSWITCH);
cc->Enable(LEVELEDSHE);
// We need to enable Advanced SHE to use the Chebyshev approximation.
cc->Enable(ADVANCEDSHE);
auto keyPair = cc->KeyGen();
// We need to generate mult keys to run Chebyshev approximations.
cc->EvalMultKeyGen(keyPair.secretKey);
std::vector<std::complex<double>> input{-4.0, -3.0, -2.0, -1.0, 0.0, 1.0, 2.0, 3.0, 4.0};
size_t encodedLength = input.size();
Plaintext plaintext = cc->MakeCKKSPackedPlaintext(input);
auto ciphertext = cc->Encrypt(keyPair.publicKey, plaintext);
double lowerBound = -5;
double upperBound = 5;
auto result = cc->EvalLogistic(ciphertext, lowerBound, upperBound, polyDegree);
Plaintext plaintextDec;
cc->Decrypt(keyPair.secretKey, result, &plaintextDec);
plaintextDec->SetLength(encodedLength);
std::vector<std::complex<double>> expectedOutput(
{0.0179885, 0.0474289, 0.119205, 0.268936, 0.5, 0.731064, 0.880795, 0.952571, 0.982011});
std::cout << "Expected output\n\t" << expectedOutput << std::endl;
std::vector<std::complex<double>> finalResult = plaintextDec->GetCKKSPackedValue();
std::cout << "Actual output\n\t" << finalResult << std::endl << std::endl;
}
void EvalFunctionExample() {
std::cout << "--------------------------------- EVAL SQUARE ROOT FUNCTION ---------------------------------"
<< std::endl;
CCParams<CryptoContextCKKSRNS> parameters;
// We set a smaller ring dimension to improve performance for this example.
// In production environments, the security level should be set to
// HEStd_128_classic, HEStd_192_classic, or HEStd_256_classic for 128-bit, 192-bit,
// or 256-bit security, respectively.
parameters.SetSecurityLevel(HEStd_NotSet);
parameters.SetRingDim(1 << 10);
#if NATIVEINT == 128
usint scalingModSize = 78;
usint firstModSize = 89;
#else
usint scalingModSize = 50;
usint firstModSize = 60;
#endif
parameters.SetScalingModSize(scalingModSize);
parameters.SetFirstModSize(firstModSize);
// Choosing a higher degree yields better precision, but a longer runtime.
uint32_t polyDegree = 50;
// The multiplicative depth depends on the polynomial degree.
// See the FUNCTION_EVALUATION.md file for a table mapping polynomial degrees to multiplicative depths.
uint32_t multDepth = 7;
parameters.SetMultiplicativeDepth(multDepth);
CryptoContext<DCRTPoly> cc = GenCryptoContext(parameters);
cc->Enable(PKE);
cc->Enable(KEYSWITCH);
cc->Enable(LEVELEDSHE);
// We need to enable Advanced SHE to use the Chebyshev approximation.
cc->Enable(ADVANCEDSHE);
auto keyPair = cc->KeyGen();
// We need to generate mult keys to run Chebyshev approximations.
cc->EvalMultKeyGen(keyPair.secretKey);
std::vector<std::complex<double>> input{1, 2, 3, 4, 5, 6, 7, 8, 9};
size_t encodedLength = input.size();
Plaintext plaintext = cc->MakeCKKSPackedPlaintext(input);
auto ciphertext = cc->Encrypt(keyPair.publicKey, plaintext);
double lowerBound = 0;
double upperBound = 10;
// We can input any lambda function, which inputs a double and returns a double.
auto result = cc->EvalChebyshevFunction([](double x) -> double { return std::sqrt(x); }, ciphertext, lowerBound,
upperBound, polyDegree);
Plaintext plaintextDec;
cc->Decrypt(keyPair.secretKey, result, &plaintextDec);
plaintextDec->SetLength(encodedLength);
std::vector<std::complex<double>> expectedOutput(
{1, 1.414213, 1.732050, 2, 2.236067, 2.449489, 2.645751, 2.828427, 3});
std::cout << "Expected output\n\t" << expectedOutput << std::endl;
std::vector<std::complex<double>> finalResult = plaintextDec->GetCKKSPackedValue();
std::cout << "Actual output\n\t" << finalResult << std::endl << std::endl;
}