correct param set for GOST R 34.10 verification

Identity.cpp

@@ -97,14 +97,14 @@ namespace data
 				}	
 				case SIGNING_KEY_TYPE_EDDSA_SHA512_ED25519:
 				{
-					size_t padding =  128 - i2p::crypto::EDDSA25519_PUBLIC_KEY_LENGTH; // 96 = 128 - 32
+					size_t padding = 128 - i2p::crypto::EDDSA25519_PUBLIC_KEY_LENGTH; // 96 = 128 - 32
 					RAND_bytes (m_StandardIdentity.signingKey, padding);
 					memcpy (m_StandardIdentity.signingKey + padding, signingKey, i2p::crypto::EDDSA25519_PUBLIC_KEY_LENGTH);
 					break;
 				}	
 				case SIGNING_KEY_TYPE_GOSTR3410_A_GOSTR3411:
 				{	
-					size_t padding =  128 - i2p::crypto::GOSTR3410_PUBLIC_KEY_LENGTH; // 64 = 128 - 64
+					size_t padding = 128 - i2p::crypto::GOSTR3410_PUBLIC_KEY_LENGTH; // 64 = 128 - 64
 					RAND_bytes (m_StandardIdentity.signingKey, padding);
 					memcpy (m_StandardIdentity.signingKey + padding, signingKey, i2p::crypto::GOSTR3410_PUBLIC_KEY_LENGTH);
 					break;
@@ -380,7 +380,7 @@ namespace data
 			case SIGNING_KEY_TYPE_GOSTR3410_A_GOSTR3411:
 			{	
 				size_t padding =  128 - i2p::crypto::GOSTR3410_PUBLIC_KEY_LENGTH; // 64 = 128 - 64
-				UpdateVerifier (new i2p::crypto::GOSTR3410Verifier (m_StandardIdentity.signingKey + padding));
+				UpdateVerifier (new i2p::crypto::GOSTR3410Verifier (i2p::crypto::eGOSTR3410CryptoProA, m_StandardIdentity.signingKey + padding));
 				break;
 			}		
 			default:

Signature.cpp

@@ -532,6 +532,13 @@ namespace crypto
 				return EC_POINT_get_affine_coordinates_GFp (m_Group, p, x, y, nullptr);
 			}
 
+			EC_POINT * CreatePoint (const BIGNUM * x, const BIGNUM * y) const
+			{
+				EC_POINT * p = EC_POINT_new (m_Group);
+				EC_POINT_set_affine_coordinates_GFp (m_Group, p, x, y, nullptr);
+				return p;
+			}
+
 			void Sign (const BIGNUM * priv, const BIGNUM * digest, BIGNUM * r, BIGNUM * s)
 			{
 				BN_CTX * ctx = BN_CTX_new ();
@@ -551,6 +558,31 @@ namespace crypto
 				BN_CTX_free (ctx);
 			}
 
+			bool Verify (const EC_POINT * pub, const BIGNUM * digest, const BIGNUM * r, const BIGNUM * s)
+			{
+				BN_CTX * ctx = BN_CTX_new ();
+				BN_CTX_start (ctx);
+				BIGNUM * q = BN_CTX_get (ctx);
+				EC_GROUP_get_order(m_Group, q, ctx);
+				BIGNUM * h = BN_CTX_get (ctx);
+				BN_mod (h, digest, q, ctx); // h = digest % q
+				BN_mod_inverse (h, h, q, ctx); // 1/h mod q
+				BIGNUM * z1 = BN_CTX_get (ctx);
+				BN_mod_mul (z1, s, h, q, ctx); // z1 = s/h
+				BIGNUM * z2 = BN_CTX_get (ctx);				
+				BN_sub (z2, q, r); // z2 = -r
+ 				BN_mod_mul (z2, z2, h, q, ctx); // z2 = -r/h
+				EC_POINT * C = EC_POINT_new (m_Group);
+				EC_POINT_mul (m_Group, C, z1, pub, z2, ctx); // z1*P + z2*pub
+				BIGNUM * x = BN_CTX_get (ctx);	
+				GetXY  (C, x, nullptr); // Cx
+				BN_mod (x, x, q, ctx); // Cx % q
+				bool ret = !BN_cmp (x, r); // Cx = r ?
+				EC_POINT_free (C);
+				BN_CTX_end (ctx);
+				BN_CTX_free (ctx);
+				return ret;
+			}
 			
 		private:
 
@@ -614,14 +646,34 @@ namespace crypto
 		return g_GOSTR3410Curves[paramSet]; 
 	}	
 
+	GOSTR3410Verifier::GOSTR3410Verifier (GOSTR3410ParamSet paramSet, const uint8_t * signingKey):
+		m_ParamSet (paramSet)
+	{ 
+		BIGNUM * x = BN_bin2bn (signingKey, GOSTR3410_PUBLIC_KEY_LENGTH/2, NULL);
+		BIGNUM * y = BN_bin2bn (signingKey + GOSTR3410_PUBLIC_KEY_LENGTH/2, GOSTR3410_PUBLIC_KEY_LENGTH/2, NULL);
+		m_PublicKey = GetGOSTR3410Curve (m_ParamSet)->CreatePoint (x, y);
+		BN_free (x); BN_free (y);
+	} 
+
+	bool GOSTR3410Verifier::Verify (const uint8_t * buf, size_t len, const uint8_t * signature) const
+	{
+		uint8_t digest[32];
+		GOSTR3411 (buf, len, digest);
+		BIGNUM * d = BN_bin2bn (digest, 32, nullptr);
+		BIGNUM * r = BN_bin2bn (signature, GetSignatureLen ()/2, NULL);
+		BIGNUM * s = BN_bin2bn (signature + GetSignatureLen ()/2, GetSignatureLen ()/2, NULL);
+		bool ret = GetGOSTR3410Curve (m_ParamSet)->Verify (m_PublicKey, d, r, s);
+		BN_free (d); BN_free (r); BN_free (s);	
+		return ret;
+	}
+
 	void GOSTR3410Signer::Sign (const uint8_t * buf, int len, uint8_t * signature) const
 	{
 		uint8_t digest[32];
 		GOSTR3411 (buf, len, digest);
 		BIGNUM * d = BN_bin2bn (digest, 32, nullptr); 
 		BIGNUM * r = BN_new (), * s = BN_new ();
-		const auto& curve = GetGOSTR3410Curve (m_ParamSet);
+		GetGOSTR3410Curve (m_ParamSet)->Sign (m_PrivateKey, d, r, s);
-		curve->Sign (m_PrivateKey, d, r, s);
 		bn2buf (r, signature, GOSTR3410_SIGNATURE_LENGTH/2);
 		bn2buf (s, signature + GOSTR3410_SIGNATURE_LENGTH/2, GOSTR3410_SIGNATURE_LENGTH/2);
 		BN_free (d); BN_free (r); BN_free (s);

Signature.h

@@ -462,36 +462,18 @@ namespace crypto
 	{
 		public:
 
-			GOSTR3410Verifier (const uint8_t * signingKey) 
+			GOSTR3410Verifier (GOSTR3410ParamSet paramSet, const uint8_t * signingKey);
-			{ 
+			~GOSTR3410Verifier () { EC_POINT_free (m_PublicKey); }
-				m_PublicKey = EVP_PKEY_new (); 
-				EC_KEY * ecKey = EC_KEY_new ();
-				EVP_PKEY_assign (m_PublicKey, NID_id_GostR3410_2001, ecKey);
-				EVP_PKEY_copy_parameters (m_PublicKey, GetGostPKEY ());		
-				BIGNUM * x = BN_bin2bn (signingKey, GOSTR3410_PUBLIC_KEY_LENGTH/2, NULL);
-				BIGNUM * y = BN_bin2bn (signingKey + GOSTR3410_PUBLIC_KEY_LENGTH/2, GOSTR3410_PUBLIC_KEY_LENGTH/2, NULL);
-				EC_KEY_set_public_key_affine_coordinates (ecKey, x, y);
-				BN_free (x); BN_free (y);
-			} 
-			~GOSTR3410Verifier () { EVP_PKEY_free (m_PublicKey); }
 			
-			bool Verify (const uint8_t * buf, size_t len, const uint8_t * signature) const
+			bool Verify (const uint8_t * buf, size_t len, const uint8_t * signature) const;
-			{
-				uint8_t digest[32];
-				GOSTR3411 (buf, len, digest);
-				EVP_PKEY_CTX *ctx = EVP_PKEY_CTX_new (m_PublicKey, nullptr);
-				EVP_PKEY_verify_init (ctx);
-				int ret = EVP_PKEY_verify (ctx, signature, GOSTR3410_SIGNATURE_LENGTH, digest, 32);
-				EVP_PKEY_CTX_free (ctx);
-				return ret == 1;
-			}
 			
 			size_t GetPublicKeyLen () const { return GOSTR3410_PUBLIC_KEY_LENGTH; }
 			size_t GetSignatureLen () const { return GOSTR3410_SIGNATURE_LENGTH; }
 
 		private:
 
-			EVP_PKEY * m_PublicKey;
+			GOSTR3410ParamSet m_ParamSet;
+			EC_POINT * m_PublicKey;
 	};	
 
 	class GOSTR3410Signer: public Signer