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Tabs -> spaces (yes this breaks compatiblity with upstream)

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EinMByte 2015-07-16 23:29:52 +02:00
parent 5d78e2f5e4
commit 4412dd198d
96 changed files with 22253 additions and 22254 deletions
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120
ElGamal.h
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@ -14,74 +14,74 @@ namespace i2p
namespace crypto
{
class ElGamalEncryption
{
public:
class ElGamalEncryption
{
public:
ElGamalEncryption (const uint8_t * key)
{
CryptoPP::AutoSeededRandomPool rnd;
CryptoPP::Integer y (key, 256), k (rnd, CryptoPP::Integer::One(), elgp-1);
a = a_exp_b_mod_c (elgg, k, elgp);
b1 = a_exp_b_mod_c (y, k, elgp);
}
ElGamalEncryption (const uint8_t * key)
{
CryptoPP::AutoSeededRandomPool rnd;
CryptoPP::Integer y (key, 256), k (rnd, CryptoPP::Integer::One(), elgp-1);
a = a_exp_b_mod_c (elgg, k, elgp);
b1 = a_exp_b_mod_c (y, k, elgp);
}
void Encrypt (const uint8_t * data, int len, uint8_t * encrypted, bool zeroPadding = false) const
{
// calculate b = b1*m mod p
uint8_t m[255];
m[0] = 0xFF;
memcpy (m+33, data, len);
CryptoPP::SHA256().CalculateDigest(m+1, m+33, 222);
CryptoPP::Integer b (a_times_b_mod_c (b1, CryptoPP::Integer (m, 255), elgp));
void Encrypt (const uint8_t * data, int len, uint8_t * encrypted, bool zeroPadding = false) const
{
// calculate b = b1*m mod p
uint8_t m[255];
m[0] = 0xFF;
memcpy (m+33, data, len);
CryptoPP::SHA256().CalculateDigest(m+1, m+33, 222);
CryptoPP::Integer b (a_times_b_mod_c (b1, CryptoPP::Integer (m, 255), elgp));
// copy a and b
if (zeroPadding)
{
encrypted[0] = 0;
a.Encode (encrypted + 1, 256);
encrypted[257] = 0;
b.Encode (encrypted + 258, 256);
}
else
{
a.Encode (encrypted, 256);
b.Encode (encrypted + 256, 256);
}
}
// copy a and b
if (zeroPadding)
{
encrypted[0] = 0;
a.Encode (encrypted + 1, 256);
encrypted[257] = 0;
b.Encode (encrypted + 258, 256);
}
else
{
a.Encode (encrypted, 256);
b.Encode (encrypted + 256, 256);
}
}
private:
private:
CryptoPP::Integer a, b1;
};
CryptoPP::Integer a, b1;
};
inline bool ElGamalDecrypt (const uint8_t * key, const uint8_t * encrypted,
uint8_t * data, bool zeroPadding = false)
{
CryptoPP::Integer x(key, 256), a(zeroPadding? encrypted +1 : encrypted, 256),
b(zeroPadding? encrypted + 258 :encrypted + 256, 256);
uint8_t m[255];
a_times_b_mod_c (b, a_exp_b_mod_c (a, elgp - x - 1, elgp), elgp).Encode (m, 255);
if (!CryptoPP::SHA256().VerifyDigest (m + 1, m + 33, 222))
{
LogPrint ("ElGamal decrypt hash doesn't match");
return false;
}
memcpy (data, m + 33, 222);
return true;
}
inline bool ElGamalDecrypt (const uint8_t * key, const uint8_t * encrypted,
uint8_t * data, bool zeroPadding = false)
{
CryptoPP::Integer x(key, 256), a(zeroPadding? encrypted +1 : encrypted, 256),
b(zeroPadding? encrypted + 258 :encrypted + 256, 256);
uint8_t m[255];
a_times_b_mod_c (b, a_exp_b_mod_c (a, elgp - x - 1, elgp), elgp).Encode (m, 255);
if (!CryptoPP::SHA256().VerifyDigest (m + 1, m + 33, 222))
{
LogPrint ("ElGamal decrypt hash doesn't match");
return false;
}
memcpy (data, m + 33, 222);
return true;
}
inline void GenerateElGamalKeyPair (CryptoPP::RandomNumberGenerator& rnd, uint8_t * priv, uint8_t * pub)
{
#if defined(__x86_64__) || defined(__i386__) || defined(_MSC_VER)
rnd.GenerateBlock (priv, 256);
a_exp_b_mod_c (elgg, CryptoPP::Integer (priv, 256), elgp).Encode (pub, 256);
inline void GenerateElGamalKeyPair (CryptoPP::RandomNumberGenerator& rnd, uint8_t * priv, uint8_t * pub)
{
#if defined(__x86_64__) || defined(__i386__) || defined(_MSC_VER)
rnd.GenerateBlock (priv, 256);
a_exp_b_mod_c (elgg, CryptoPP::Integer (priv, 256), elgp).Encode (pub, 256);
#else
CryptoPP::DH dh (elgp, elgg);
dh.GenerateKeyPair(rnd, priv, pub);
#endif
}
CryptoPP::DH dh (elgp, elgg);
dh.GenerateKeyPair(rnd, priv, pub);
#endif
}
}
}
}
#endif