Post-Quantum. MLDSA44 verifier

libi2pd/Crypto.h

@@ -33,6 +33,9 @@
 #	if (!defined(LIBRESSL_VERSION_NUMBER) && (OPENSSL_VERSION_NUMBER != 0x030000000)) // 3.0.0, regression in SipHash, not implemented in LibreSSL
 #		define OPENSSL_SIPHASH 1
 #	endif
+#	if (OPENSSL_VERSION_NUMBER >= 0x030500000) // 3.5.0
+#		define OPENSSL_PQ 1
+#	endif
 #endif
 
 namespace i2p

libi2pd/Identity.cpp

@@ -119,6 +119,16 @@ namespace data
 					memcpy (m_StandardIdentity.signingKey, signingKey, i2p::crypto::GOSTR3410_512_PUBLIC_KEY_LENGTH);
 					break;
 				}
+#if OPENSSL_PQ
+				case SIGNING_KEY_TYPE_MLDSA44:
+				{
+					memcpy (m_StandardIdentity, signingKey, 384);
+					excessLen = i2p::crypto::MLDSA44_PUBLIC_KEY_LENGTH - 384;
+					excessBuf = new uint8_t[excessLen];
+					memcpy (excessBuf, signingKey + 384, excessLen);
+					break;
+				}	
+#endif					
 				default:
 					LogPrint (eLogError, "Identity: Signing key type ", (int)type, " is not supported");
 			}
@@ -352,6 +362,10 @@ namespace data
 				return new i2p::crypto::GOSTR3410_512_Verifier (i2p::crypto::eGOSTR3410TC26A512);
 			case SIGNING_KEY_TYPE_REDDSA_SHA512_ED25519:
 				return new i2p::crypto::RedDSA25519Verifier ();
+#if OPENSSL_PQ				
+			case SIGNING_KEY_TYPE_MLDSA44:
+				return new i2p::crypto::MLDSA44Verifier ();
+#endif				
 			case SIGNING_KEY_TYPE_RSA_SHA256_2048:
 			case SIGNING_KEY_TYPE_RSA_SHA384_3072:
 			case SIGNING_KEY_TYPE_RSA_SHA512_4096:
@@ -373,6 +387,18 @@ namespace data
 				auto keyLen = verifier->GetPublicKeyLen ();
 				if (keyLen <= 128)
 					verifier->SetPublicKey (m_StandardIdentity.signingKey + 128 - keyLen);
+#if OPENSSL_PQ
+				else if (keyLen > 384)
+				{
+					// for post-quantum
+					uint8_t * signingKey = new uint8_t[keyLen];
+					memcpy (signingKey, m_StandardIdentity.signingKey, 384);
+					size_t excessLen = keyLen - 384;
+					memcpy (signingKey + 384, m_ExtendedBuffer + 4, excessLen); // right after signing and crypto key types
+					verifier->SetPublicKey (signingKey);
+					delete[] signingKey;
+				}	
+#endif				
 				else
 				{
 					// for P521

libi2pd/Identity.h

@@ -55,6 +55,8 @@ namespace data
 		Identity& operator=(const Keys& keys);
 		size_t FromBuffer (const uint8_t * buf, size_t len);
 		IdentHash Hash () const;
+		operator uint8_t * () { return reinterpret_cast<uint8_t *>(this); }
+		operator const uint8_t * () const { return reinterpret_cast<const uint8_t *>(this); }
 	};
 
 	Keys CreateRandomKeys ();
@@ -77,7 +79,8 @@ namespace data
 	const uint16_t SIGNING_KEY_TYPE_GOSTR3410_CRYPTO_PRO_A_GOSTR3411_256 = 9;
 	const uint16_t SIGNING_KEY_TYPE_GOSTR3410_TC26_A_512_GOSTR3411_512 = 10; // approved by FSB
 	const uint16_t SIGNING_KEY_TYPE_REDDSA_SHA512_ED25519 = 11; // for LeaseSet2 only
-
+	const uint16_t SIGNING_KEY_TYPE_MLDSA44 = 15;
+	
 	typedef uint16_t SigningKeyType;
 	typedef uint16_t CryptoKeyType;
 
@@ -132,7 +135,7 @@ namespace data
 			IdentHash m_IdentHash;
 			std::unique_ptr<i2p::crypto::Verifier> m_Verifier;
 			size_t m_ExtendedLen;
-			uint8_t m_ExtendedBuffer[MAX_EXTENDED_BUFFER_SIZE];
+			uint8_t m_ExtendedBuffer[MAX_EXTENDED_BUFFER_SIZE]; // TODO: support PQ keys
 	};
 
 	size_t GetIdentityBufferLen (const uint8_t * buf, size_t len); // return actual identity length in buffer

libi2pd/Signature.cpp

@@ -199,6 +199,40 @@ namespace crypto
 		else
 			LogPrint (eLogError, "EdDSA signing key is not set");
 	}		
+#endif	
+		
+#if OPENSSL_PQ
+	MLDSA44Verifier::MLDSA44Verifier ():
+		m_Pkey (nullptr)
+	{
+	}
+
+	MLDSA44Verifier::~MLDSA44Verifier ()
+	{
+		EVP_PKEY_free (m_Pkey);
+	}
+
+	void MLDSA44Verifier::SetPublicKey (const uint8_t * signingKey)
+	{
+		if (m_Pkey) EVP_PKEY_free (m_Pkey);
+		m_Pkey = EVP_PKEY_new_raw_public_key (EVP_PKEY_ML_DSA_44, NULL, signingKey, GetPublicKeyLen ());
+	}
+
+	bool MLDSA44Verifier::Verify (const uint8_t * buf, size_t len, const uint8_t * signature) const
+	{
+		if (m_Pkey)
+		{	
+			EVP_MD_CTX * ctx = EVP_MD_CTX_create ();
+			EVP_DigestVerifyInit (ctx, NULL, NULL, NULL, m_Pkey);
+			auto ret = EVP_DigestVerify (ctx, signature, GetSignatureLen (), buf, len);
+			EVP_MD_CTX_destroy (ctx);	
+			return ret;	
+		}	
+		else
+			LogPrint (eLogError, "MLDSA44 verification key is not set");
+		return false;
+	}
+		
 #endif		
 }
 }

libi2pd/Signature.h

@@ -560,6 +560,30 @@ namespace crypto
 		RedDSA25519Signer signer (signingPrivateKey);
 		memcpy (signingPublicKey, signer.GetPublicKey (), EDDSA25519_PUBLIC_KEY_LENGTH);
 	}
+	
+#if OPENSSL_PQ
+	
+	// Post-Quantum
+	const size_t MLDSA44_PUBLIC_KEY_LENGTH = 1312;
+	const size_t MLDSA44_SIGNATURE_LENGTH = 2420;
+	class MLDSA44Verifier: public Verifier
+	{
+		public:
+
+			MLDSA44Verifier ();
+			void SetPublicKey (const uint8_t * signingKey);
+			~MLDSA44Verifier ();
+
+			bool Verify (const uint8_t * buf, size_t len, const uint8_t * signature) const;
+
+			size_t GetPublicKeyLen () const { return MLDSA44_PUBLIC_KEY_LENGTH; };
+			size_t GetSignatureLen () const { return MLDSA44_SIGNATURE_LENGTH; };
+
+		private:
+			
+			EVP_PKEY * m_Pkey;
+	};
+#endif	
 }
 }