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@ -17,14 +17,13 @@ namespace crypto
@@ -17,14 +17,13 @@ namespace crypto
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{ |
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public: |
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ElGamalEncryption (const uint8_t * key, bool zeroPadding = false): |
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ElGamalEncryption (const uint8_t * key): |
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y (key, 256), k (rnd, CryptoPP::Integer::One(), elgp-1), |
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a (a_exp_b_mod_c (elgg, k, elgp)), b1 (a_exp_b_mod_c (y, k, elgp)), |
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m_ZeroPadding (zeroPadding) |
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a (a_exp_b_mod_c (elgg, k, elgp)), b1 (a_exp_b_mod_c (y, k, elgp)) |
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{ |
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} |
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void Encrypt (const uint8_t * data, int len, uint8_t * encrypted) |
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void Encrypt (const uint8_t * data, int len, uint8_t * encrypted, bool zeroPadding = false) |
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{ |
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// calculate b = b1*m mod p
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uint8_t m[255]; |
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@ -34,7 +33,7 @@ namespace crypto
@@ -34,7 +33,7 @@ namespace crypto
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CryptoPP::Integer b (a_times_b_mod_c (b1, CryptoPP::Integer (m, 255), elgp)); |
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// copy a and b
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if (m_ZeroPadding) |
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if (zeroPadding) |
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{ |
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encrypted[0] = 0; |
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a.Encode (encrypted + 1, 256); |
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@ -72,29 +71,6 @@ namespace crypto
@@ -72,29 +71,6 @@ namespace crypto
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memcpy (data, m + 33, 222); |
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return true; |
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} |
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// deprecated
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inline void ElGamalEncrypt (const uint8_t * key, const uint8_t * data, int len, |
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uint8_t * encrypted, bool zeroPadding = false) // 514 with padding and 512 without
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{ |
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CryptoPP::AutoSeededRandomPool rnd; |
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CryptoPP::Integer y(key, 256), k(rnd, CryptoPP::Integer::One(), elgp-1); |
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if (zeroPadding) |
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{ |
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encrypted[0] = 0; |
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encrypted[257] = 0; |
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} |
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a_exp_b_mod_c (elgg, k, elgp).Encode (zeroPadding ? encrypted + 1 : encrypted, 256); |
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uint8_t m[255]; |
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m[0] = 0xFF; |
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memcpy (m+33, data, len); |
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CryptoPP::SHA256().CalculateDigest(m+1, m+33, 222); |
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a_times_b_mod_c (a_exp_b_mod_c (y, k, elgp), |
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CryptoPP::Integer (m, 255), elgp).Encode (zeroPadding ? encrypted + 258 : encrypted + 256, 256); |
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} |
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} |
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} |
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