Files
MP-SPDZ/FHE/FHE_Params.cpp
Marcel Keller 6cc3fccef0 Maintenance.
2023-05-09 14:50:53 +10:00

126 lines
2.6 KiB
C++

#include "FHE_Params.h"
#include "NTL-Subs.h"
#include "FHE/Ring_Element.h"
#include "Tools/Exceptions.h"
#include "Protocols/HemiOptions.h"
#include "Processor/OnlineOptions.h"
FHE_Params::FHE_Params(int n_mults, int drown_sec) :
FFTData(n_mults + 1), Chi(0.7), sec_p(drown_sec), matrix_dim(1)
{
}
void FHE_Params::set(const Ring& R,
const vector<bigint>& primes)
{
if (primes.size() != FFTData.size())
throw runtime_error("wrong number of primes");
for (size_t i = 0; i < FFTData.size(); i++)
FFTData[i].init(R,primes[i]);
set_sec(sec_p);
}
void FHE_Params::set_sec(int sec)
{
assert(sec >= 0);
sec_p=sec;
Bval=1; Bval=Bval<<sec_p;
Bval=FFTData[0].get_prime()/(2*(1+Bval));
}
void FHE_Params::set_min_sec(int sec)
{
set_sec(max(sec, sec_p));
}
void FHE_Params::set_matrix_dim(int matrix_dim)
{
assert(matrix_dim > 0);
if (FFTData[0].get_prime() != 0)
throw runtime_error("cannot change matrix dimension after parameter generation");
this->matrix_dim = matrix_dim;
}
void FHE_Params::set_matrix_dim_from_options()
{
set_matrix_dim(
HemiOptions::singleton.plain_matmul ?
1 : OnlineOptions::singleton.batch_size);
}
bigint FHE_Params::Q() const
{
bigint res = FFTData[0].get_prime();
for (size_t i = 1; i < FFTData.size(); i++)
res *= FFTData[i].get_prime();
return res;
}
void FHE_Params::pack(octetStream& o) const
{
o.store(FFTData.size());
for(auto& fd: FFTData)
fd.pack(o);
Chi.pack(o);
Bval.pack(o);
o.store(sec_p);
o.store(matrix_dim);
fd.pack(o);
}
void FHE_Params::unpack(octetStream& o)
{
size_t size;
o.get(size);
FFTData.resize(size);
for (auto& fd : FFTData)
fd.unpack(o);
Chi.unpack(o);
Bval.unpack(o);
o.get(sec_p);
o.get(matrix_dim);
fd.unpack(o);
}
bool FHE_Params::operator!=(const FHE_Params& other) const
{
if (FFTData != other.FFTData or Chi != other.Chi or sec_p != other.sec_p
or Bval != other.Bval)
{
return true;
}
else
return false;
}
void FHE_Params::basic_generation_mod_prime(int plaintext_length)
{
if (n_mults() == 0)
generate_semi_setup(plaintext_length, 0, *this, fd, false);
else
{
Parameters parameters(1, plaintext_length, 0);
parameters.generate_setup(*this, fd);
}
}
template<>
const FFT_Data& FHE_Params::get_plaintext_field_data() const
{
return fd;
}
template<>
const P2Data& FHE_Params::get_plaintext_field_data() const
{
throw not_implemented();
}
bigint FHE_Params::get_plaintext_modulus() const
{
return fd.get_prime();
}