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#include "pch.h"
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#include "rabin.h"
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#include "nbtheory.h"
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#include "asn.h"
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#include "sha.h"
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#include "modarith.h"
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00010
#include "oaep.cpp"
00011
00012 NAMESPACE_BEGIN(CryptoPP)
00013
00014 void
RabinFunction::BERDecode(
BufferedTransformation &bt)
00015 {
00016
BERSequenceDecoder seq(bt);
00017 m_n.BERDecode(seq);
00018 m_r.BERDecode(seq);
00019 m_s.BERDecode(seq);
00020 seq.
MessageEnd();
00021 }
00022
00023
void RabinFunction::DEREncode(
BufferedTransformation &bt)
const
00024
{
00025
DERSequenceEncoder seq(bt);
00026 m_n.
DEREncode(seq);
00027 m_r.
DEREncode(seq);
00028 m_s.
DEREncode(seq);
00029 seq.
MessageEnd();
00030 }
00031
00032
Integer RabinFunction::ApplyFunction(
const Integer &in)
const
00033
{
00034 DoQuickSanityCheck();
00035
00036
Integer out = in.
Squared()%m_n;
00037
if (in.
IsOdd())
00038 out = out*m_r%m_n;
00039
if (Jacobi(in, m_n)==-1)
00040 out = out*m_s%m_n;
00041
return out;
00042 }
00043
00044 bool RabinFunction::Validate(
RandomNumberGenerator &rng,
unsigned int level)
const
00045
{
00046
bool pass =
true;
00047 pass = pass && m_n >
Integer::One() && m_n%4 == 1;
00048 pass = pass && m_r >
Integer::One() && m_r < m_n;
00049 pass = pass && m_s >
Integer::One() && m_s < m_n;
00050
if (level >= 1)
00051 pass = pass && Jacobi(m_r, m_n) == -1 && Jacobi(m_s, m_n) == -1;
00052
return pass;
00053 }
00054
00055 bool RabinFunction::GetVoidValue(
const char *name,
const std::type_info &valueType,
void *pValue)
const
00056
{
00057
return GetValueHelper(
this, name, valueType, pValue).Assignable()
00058 CRYPTOPP_GET_FUNCTION_ENTRY(Modulus)
00059 CRYPTOPP_GET_FUNCTION_ENTRY(QuadraticResidueModPrime1)
00060 CRYPTOPP_GET_FUNCTION_ENTRY(QuadraticResidueModPrime2)
00061 ;
00062 }
00063
00064 void RabinFunction::AssignFrom(
const NameValuePairs &source)
00065 {
00066 AssignFromHelper(
this, source)
00067 CRYPTOPP_SET_FUNCTION_ENTRY(Modulus)
00068 CRYPTOPP_SET_FUNCTION_ENTRY(QuadraticResidueModPrime1)
00069 CRYPTOPP_SET_FUNCTION_ENTRY(QuadraticResidueModPrime2)
00070 ;
00071 }
00072
00073
00074
00075
00076
00077 void InvertibleRabinFunction::GenerateRandom(
RandomNumberGenerator &rng,
const NameValuePairs &alg)
00078 {
00079
int modulusSize = 2048;
00080 alg.
GetIntValue(
"ModulusSize", modulusSize) || alg.
GetIntValue(
"KeySize", modulusSize);
00081
00082
if (modulusSize < 16)
00083
throw InvalidArgument(
"InvertibleRabinFunction: specified modulus size is too small");
00084
00085
00086
bool rFound=
false, sFound=
false;
00087
Integer t=2;
00088
00089
const NameValuePairs &primeParam = MakeParametersForTwoPrimesOfEqualSize(modulusSize)
00090 (
"EquivalentTo", 3)(
"Mod", 4);
00091 m_p.
GenerateRandom(rng, primeParam);
00092 m_q.
GenerateRandom(rng, primeParam);
00093
00094
while (!(rFound && sFound))
00095 {
00096
int jp = Jacobi(t, m_p);
00097
int jq = Jacobi(t, m_q);
00098
00099
if (!rFound && jp==1 && jq==-1)
00100 {
00101 m_r = t;
00102 rFound =
true;
00103 }
00104
00105
if (!sFound && jp==-1 && jq==1)
00106 {
00107 m_s = t;
00108 sFound =
true;
00109 }
00110
00111 ++t;
00112 }
00113
00114 m_n = m_p * m_q;
00115 m_u = m_q.
InverseMod(m_p);
00116 }
00117
00118
void InvertibleRabinFunction::BERDecode(
BufferedTransformation &bt)
00119 {
00120
BERSequenceDecoder seq(bt);
00121 m_n.
BERDecode(seq);
00122 m_r.
BERDecode(seq);
00123 m_s.
BERDecode(seq);
00124 m_p.
BERDecode(seq);
00125 m_q.
BERDecode(seq);
00126 m_u.
BERDecode(seq);
00127 seq.
MessageEnd();
00128 }
00129
00130
void InvertibleRabinFunction::DEREncode(
BufferedTransformation &bt)
const
00131
{
00132
DERSequenceEncoder seq(bt);
00133 m_n.
DEREncode(seq);
00134 m_r.
DEREncode(seq);
00135 m_s.
DEREncode(seq);
00136 m_p.
DEREncode(seq);
00137 m_q.
DEREncode(seq);
00138 m_u.
DEREncode(seq);
00139 seq.
MessageEnd();
00140 }
00141
00142
Integer InvertibleRabinFunction::CalculateInverse(
RandomNumberGenerator &rng,
const Integer &in)
const
00143
{
00144 DoQuickSanityCheck();
00145
00146
ModularArithmetic modn(m_n);
00147
Integer r(rng, Integer::One(), m_n - Integer::One());
00148 r = modn.
Square(r);
00149
Integer r2 = modn.
Square(r);
00150
Integer c = modn.
Multiply(in, r2);
00151
00152
Integer cp=c%m_p, cq=c%m_q;
00153
00154
int jp = Jacobi(cp, m_p);
00155
int jq = Jacobi(cq, m_q);
00156
00157
if (jq==-1)
00158 {
00159 cp = cp*EuclideanMultiplicativeInverse(m_r, m_p)%m_p;
00160 cq = cq*EuclideanMultiplicativeInverse(m_r, m_q)%m_q;
00161 }
00162
00163
if (jp==-1)
00164 {
00165 cp = cp*EuclideanMultiplicativeInverse(m_s, m_p)%m_p;
00166 cq = cq*EuclideanMultiplicativeInverse(m_s, m_q)%m_q;
00167 }
00168
00169 cp = ModularSquareRoot(cp, m_p);
00170 cq = ModularSquareRoot(cq, m_q);
00171
00172
if (jp==-1)
00173 cp = m_p-cp;
00174
00175
Integer out = CRT(cq, m_q, cp, m_p, m_u);
00176
00177 out = modn.
Divide(out, r);
00178
00179
if ((jq==-1 && out.
IsEven()) || (jq==1 && out.
IsOdd()))
00180 out = m_n-out;
00181
00182
return out;
00183 }
00184
00185 bool InvertibleRabinFunction::Validate(
RandomNumberGenerator &rng,
unsigned int level)
const
00186
{
00187
bool pass = RabinFunction::Validate(rng, level);
00188 pass = pass && m_p >
Integer::One() && m_p%4 == 3 && m_p < m_n;
00189 pass = pass && m_q >
Integer::One() && m_q%4 == 3 && m_q < m_n;
00190 pass = pass && m_u.
IsPositive() && m_u < m_p;
00191
if (level >= 1)
00192 {
00193 pass = pass && m_p * m_q == m_n;
00194 pass = pass && m_u * m_q % m_p == 1;
00195 pass = pass && Jacobi(m_r, m_p) == 1;
00196 pass = pass && Jacobi(m_r, m_q) == -1;
00197 pass = pass && Jacobi(m_s, m_p) == -1;
00198 pass = pass && Jacobi(m_s, m_q) == 1;
00199 }
00200
if (level >= 2)
00201 pass = pass && VerifyPrime(rng, m_p, level-2) && VerifyPrime(rng, m_q, level-2);
00202
return pass;
00203 }
00204
00205 bool InvertibleRabinFunction::GetVoidValue(
const char *name,
const std::type_info &valueType,
void *pValue)
const
00206
{
00207
return GetValueHelper<RabinFunction>(
this, name, valueType, pValue).Assignable()
00208 CRYPTOPP_GET_FUNCTION_ENTRY(Prime1)
00209 CRYPTOPP_GET_FUNCTION_ENTRY(Prime2)
00210 CRYPTOPP_GET_FUNCTION_ENTRY(MultiplicativeInverseOfPrime2ModPrime1)
00211 ;
00212 }
00213
00214 void InvertibleRabinFunction::AssignFrom(
const NameValuePairs &source)
00215 {
00216 AssignFromHelper<RabinFunction>(
this, source)
00217 CRYPTOPP_SET_FUNCTION_ENTRY(Prime1)
00218 CRYPTOPP_SET_FUNCTION_ENTRY(Prime2)
00219 CRYPTOPP_SET_FUNCTION_ENTRY(MultiplicativeInverseOfPrime2ModPrime1)
00220 ;
00221 }
00222
00223 NAMESPACE_END