mirror of https://github.com/PurpleI2P/i2pd.git
I2P: End-to-End encrypted and anonymous Internet
https://i2pd.website/
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
122 lines
4.1 KiB
122 lines
4.1 KiB
10 years ago
|
#include <memory>
|
||
10 years ago
|
#include <cryptopp/integer.h>
|
||
|
#include <cryptopp/eccrypto.h>
|
||
10 years ago
|
#include "Log.h"
|
||
10 years ago
|
#include "Signature.h"
|
||
|
|
||
|
namespace i2p
|
||
|
{
|
||
|
namespace crypto
|
||
|
{
|
||
10 years ago
|
class Ed25519
|
||
|
{
|
||
|
public:
|
||
|
|
||
|
Ed25519 ()
|
||
|
{
|
||
|
q = CryptoPP::Integer::Power2 (255) - CryptoPP::Integer (19); // 2^255-19
|
||
|
l = CryptoPP::Integer::Power2 (252) + CryptoPP::Integer ("27742317777372353535851937790883648493");
|
||
|
// 2^252 + 27742317777372353535851937790883648493
|
||
|
d = CryptoPP::Integer (-121665) * CryptoPP::Integer (121666).InverseMod (q); // -121665/121666
|
||
|
I = a_exp_b_mod_c (CryptoPP::Integer::Two (), (q - CryptoPP::Integer::One ()).DividedBy (4), q);
|
||
|
B = DecodePoint (CryptoPP::Integer (4)*CryptoPP::Integer (5).InverseMod (q));
|
||
|
}
|
||
|
|
||
|
CryptoPP::ECP::Point DecodePublicKey (const uint8_t * key) const
|
||
|
{
|
||
|
return DecodePoint (CryptoPP::Integer (key, 32));
|
||
|
}
|
||
|
|
||
|
CryptoPP::ECP::Point GeneratePublicKey (const uint8_t * privateKey) const
|
||
|
{
|
||
|
return Mul (B, CryptoPP::Integer (privateKey, 32));
|
||
|
}
|
||
|
|
||
|
private:
|
||
|
|
||
|
CryptoPP::ECP::Point Sum (const CryptoPP::ECP::Point& p1, const CryptoPP::ECP::Point& p2) const
|
||
|
{
|
||
|
CryptoPP::Integer m = d*p1.x*p2.x*p1.y*p2.y,
|
||
|
x = a_times_b_mod_c (p1.x*p2.y + p2.x*p1.y, (CryptoPP::Integer::One() + m).InverseMod (q), q),
|
||
|
y = a_times_b_mod_c (p1.y*p2.y + p1.x*p2.x, (CryptoPP::Integer::One() - m).InverseMod (q), q);
|
||
|
return CryptoPP::ECP::Point {x, y};
|
||
|
}
|
||
|
|
||
|
CryptoPP::ECP::Point Mul (const CryptoPP::ECP::Point& p, const CryptoPP::Integer& e) const
|
||
|
{
|
||
|
CryptoPP::ECP::Point res {0, 1};
|
||
|
if (!e.IsZero ())
|
||
|
{
|
||
|
auto bitCount = e.BitCount ();
|
||
|
for (int i = bitCount - 1; i >= 0; i--)
|
||
|
{
|
||
|
res = Sum (res, res);
|
||
|
if (e.GetBit (i)) res = Sum (res, p);
|
||
|
}
|
||
|
}
|
||
|
return res;
|
||
|
}
|
||
|
|
||
|
bool IsOnCurve (const CryptoPP::ECP::Point& p) const
|
||
|
{
|
||
|
auto x2 = p.x.Squared(), y2 = p.y.Squared ();
|
||
|
return (y2 - x2 - CryptoPP::Integer::One() - d*x2*y2).Modulo (q).IsZero ();
|
||
|
}
|
||
|
|
||
|
CryptoPP::Integer RecoverX (const CryptoPP::Integer& y) const
|
||
|
{
|
||
|
auto y2 = y.Squared ();
|
||
|
auto xx = (y2 - CryptoPP::Integer::One())*(d*y2 + CryptoPP::Integer::One()).InverseMod (q);
|
||
|
auto x = a_exp_b_mod_c (xx, (q + CryptoPP::Integer (3)).DividedBy (8), q);
|
||
|
if (!(x.Squared () - xx).Modulo (q).IsZero ())
|
||
|
x = a_times_b_mod_c (x, I, q);
|
||
|
if (x.IsOdd ()) x = q - x;
|
||
|
return x;
|
||
|
}
|
||
|
|
||
|
CryptoPP::ECP::Point DecodePoint (const CryptoPP::Integer& y) const
|
||
|
{
|
||
|
auto x = RecoverX (y);
|
||
|
CryptoPP::ECP::Point p {x, y};
|
||
|
if (!IsOnCurve (p))
|
||
|
{
|
||
|
LogPrint (eLogError, "Decoded point is not on 25519");
|
||
|
return CryptoPP::ECP::Point {0, 1};
|
||
|
}
|
||
|
return p;
|
||
|
}
|
||
|
|
||
|
private:
|
||
|
|
||
|
CryptoPP::Integer q, l, d, I;
|
||
|
CryptoPP::ECP::Point B; // base point
|
||
|
};
|
||
|
|
||
|
static std::unique_ptr<Ed25519> g_Ed25519;
|
||
|
std::unique_ptr<Ed25519>& GetEd25519 ()
|
||
|
{
|
||
|
if (!g_Ed25519)
|
||
|
g_Ed25519.reset (new Ed25519 ());
|
||
|
return g_Ed25519;
|
||
|
}
|
||
|
|
||
|
|
||
|
EDDSA25519Verifier::EDDSA25519Verifier (const uint8_t * signingKey):
|
||
|
m_PublicKey (GetEd25519 ()->DecodePublicKey (signingKey))
|
||
|
{
|
||
|
}
|
||
|
|
||
|
bool EDDSA25519Verifier::Verify (const uint8_t * buf, size_t len, const uint8_t * signature) const
|
||
|
{
|
||
|
return true; // TODO:
|
||
|
}
|
||
|
|
||
|
void EDDSA25519Signer::Sign (CryptoPP::RandomNumberGenerator& rnd, const uint8_t * buf, int len, uint8_t * signature) const
|
||
|
{
|
||
|
// TODO
|
||
|
}
|
||
10 years ago
|
}
|
||
|
}
|
||
|
|
||
|
|