diff --git a/Gost.cpp b/Gost.cpp
index 6c5d7f24..b142dbb3 100644
--- a/Gost.cpp
+++ b/Gost.cpp
@@ -131,6 +131,14 @@ namespace crypto
 				"91E38443A5E82C0D880923425712B2BB658B9196932E02C78B2582FE742DAA28",
 				"32879423AB1A0375895786C4BB46E9565FDE0B5344766740AF268ADB32322E5C"		
 			}, // tc26-2012-paramSetA-256
+			{
+				"FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFDC4",
+				"E8C2505DEDFC86DDC1BD0B2B6667F1DA34B82574761CB0E879BD081CFD0B6265EE3CB090F30D27614CB4574010DA90DD862EF9D4EBEE4761503190785A71C760",
+				"FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFDC7",
+				"FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF27E69532F48D89116FF22B8D4E0560609B4B38ABFAD2B85DCACDB1411F10B275",
+				"3",
+				"7503CFE87A836AE3A61B8816E25450E6CE5E1C93ACF1ABC1778064FDCBEFA921DF1626BE4FD036E93D75E6A50E3A41E98028FE5FC235F5B889A589CB5215F2A"		
+			}, // tc26-2012-paramSetA-512
 			{
 				"DC9203E514A721875485A529D2C722FB187BC8980EB866644DE41C68E143064546E861C0E2C9EDD92ADE71F46FCF50FF2AD97F951FDA9F2A2EB6546F39689BD3",
 				"B4C4EE28CEBC6C2C8AC12952CF37F16AC7EFB6A9F69F4B57FFDA2E4F0DE5ADE038CBC2FFF719D2C18DE0284B8BFEF3B52B8CC7A5F5BF0A3C8D2319A5312557E1",	
diff --git a/Gost.h b/Gost.h
index eb8e79f6..39a57bb2 100644
--- a/Gost.h
+++ b/Gost.h
@@ -22,6 +22,7 @@ namespace crypto
 		//eGOSTR3410CryptoProXchB,	// 1.2.643.2.2.36.1
 		// GOST R 34.10-2012		
 		eGOSTR3410TC26A256,		// 1.2.643.7.1.2.1.1.1 
+		eGOSTR3410TC26A512,		// 1.2.643.7.1.2.1.2.1
 		eGOSTR3410TC26C512,		// 1.2.643.7.1.2.1.2.3 
 		eGOSTR3410NumParamSets
 	};	
diff --git a/Signature.h b/Signature.h
index 9a8bbb06..aee8c487 100644
--- a/Signature.h
+++ b/Signature.h
@@ -535,7 +535,7 @@ namespace crypto
 			{
 				uint8_t digest[Hash::hashLen];
 				Hash::CalculateHash (buf, len, digest);
-				BIGNUM * d = BN_bin2bn (digest, 32, nullptr); 
+				BIGNUM * d = BN_bin2bn (digest, Hash::hashLen, nullptr); 
 				BIGNUM * r = BN_new (), * s = BN_new ();
 				GetGOSTR3410Curve (m_ParamSet)->Sign (m_PrivateKey, d, r, s);
 				bn2buf (r, signature, keyLen);