#ifndef SIGNATURE_H__
#define SIGNATURE_H__

#include <inttypes.h>
#include <cryptopp/dsa.h>
#include <cryptopp/asn.h>
#include <cryptopp/oids.h>
#include <cryptopp/osrng.h>
#include <cryptopp/eccrypto.h>
#include "CryptoConst.h"

namespace i2p
{
namespace crypto
{
	class Verifier
	{
		public:
			
			virtual ~Verifier () {};
			virtual bool Verify (const uint8_t * buf, size_t len, const uint8_t * signature) const = 0;
			virtual size_t GetPublicKeyLen () const = 0;
			virtual size_t GetSignatureLen () const = 0;
	};

	class Signer
	{
		public:

			virtual ~Signer () {};		
			virtual void Sign (CryptoPP::RandomNumberGenerator& rnd, const uint8_t * buf, int len, uint8_t * signature) const = 0; 
	};

	const size_t DSA_PUBLIC_KEY_LENGTH = 128;
	const size_t DSA_SIGNATURE_LENGTH = 40;	
	const size_t DSA_PRIVATE_KEY_LENGTH = DSA_SIGNATURE_LENGTH/2;
	class DSAVerifier: public Verifier
	{
		public:

			DSAVerifier (const uint8_t * signingKey)
			{
				m_PublicKey.Initialize (dsap, dsaq, dsag, CryptoPP::Integer (signingKey, DSA_PUBLIC_KEY_LENGTH));
			}
	
			bool Verify (const uint8_t * buf, size_t len, const uint8_t * signature) const
			{
				CryptoPP::DSA::Verifier verifier (m_PublicKey);
				return verifier.VerifyMessage (buf, len, signature, DSA_SIGNATURE_LENGTH);
			}	

			size_t GetPublicKeyLen () const { return DSA_PUBLIC_KEY_LENGTH; };
			size_t GetSignatureLen () const { return DSA_SIGNATURE_LENGTH; };
			
		private:

			CryptoPP::DSA::PublicKey m_PublicKey;
	};

	class DSASigner: public Signer
	{
		public:

			DSASigner (const uint8_t * signingPrivateKey)
			{
				m_PrivateKey.Initialize (dsap, dsaq, dsag, CryptoPP::Integer (signingPrivateKey, DSA_PRIVATE_KEY_LENGTH));
			}

			void Sign (CryptoPP::RandomNumberGenerator& rnd, const uint8_t * buf, int len, uint8_t * signature) const
			{
				CryptoPP::DSA::Signer signer (m_PrivateKey);
				signer.SignMessage (rnd, buf, len, signature);
			}

		private:

			CryptoPP::DSA::PrivateKey m_PrivateKey;
	};

	inline void CreateDSARandomKeys (CryptoPP::RandomNumberGenerator& rnd, uint8_t * signingPrivateKey, uint8_t * signingPublicKey)
	{
		CryptoPP::DSA::PrivateKey privateKey;
		CryptoPP::DSA::PublicKey publicKey;
		privateKey.Initialize (rnd, dsap, dsaq, dsag);
		privateKey.MakePublicKey (publicKey);
		privateKey.GetPrivateExponent ().Encode (signingPrivateKey, DSA_PRIVATE_KEY_LENGTH);	
		publicKey.GetPublicElement ().Encode (signingPublicKey, DSA_PUBLIC_KEY_LENGTH);
	}	


	const size_t ECDSAP256_PUBLIC_KEY_LENGTH = 64;
	const size_t ECDSAP256_PUBLIC_KEY_HALF_LENGTH = ECDSAP256_PUBLIC_KEY_LENGTH/2;
	const size_t ECDSAP256_SIGNATURE_LENGTH = 64;
	const size_t ECDSAP256_PRIVATE_KEY_LENGTH = ECDSAP256_SIGNATURE_LENGTH/2;		
	class ECDSAP256Verifier: public Verifier
	{
		public:

			ECDSAP256Verifier (const uint8_t * signingKey)
			{
				m_PublicKey.Initialize (CryptoPP::ASN1::secp256r1(), 
					CryptoPP::ECP::Point (CryptoPP::Integer (signingKey, ECDSAP256_PUBLIC_KEY_HALF_LENGTH), 
					CryptoPP::Integer (signingKey + ECDSAP256_PUBLIC_KEY_HALF_LENGTH, ECDSAP256_PUBLIC_KEY_HALF_LENGTH)));
			}			

			bool Verify (const uint8_t * buf, size_t len, const uint8_t * signature) const
			{
				CryptoPP::ECDSA<CryptoPP::ECP, CryptoPP::SHA256>::Verifier verifier (m_PublicKey);
				return verifier.VerifyMessage (buf, len, signature, ECDSAP256_SIGNATURE_LENGTH);
			}	

			size_t GetPublicKeyLen () const { returHTTP/1.1 200 OK
Content-Disposition: inline; filename="Signature.h"; filename*=UTF-8''Signature.h
Content-Length: 4912
Etag: "fbc02c4ecb4453b2b25f5894e54068f264f05e1e"
Last-Modified: Wed, 15 Oct 2014 18:04:23 GMT
Set-Cookie: i_like_gitea=bfedfb14fff5b19d; Path=/; HttpOnly; Secure; SameSite=Lax
Set-Cookie: _csrf=hgttsHnbP9WrY3kc2V6VFzanv9c6MTc1MzI2NzkzMzI0NDg5NTE2NA; Path=/; Max-Age=86400; HttpOnly; Secure; SameSite=Lax
Connection: close
Access-Control-Expose-Headers: Content-Disposition
Content-Type: text/plain; charset=utf-8
X-Frame-Options: SAMEORIGIN
X-Content-Type-Options: nosniff
Date: Wed, 23 Jul 2025 10:52:13 GMT
Cache-Control: public, max-age=21600, no-transform
X-Cache-Status: HIT
X-Cache-Age: 0

#ifndef SIGNATURE_H__
#define SIGNATURE_H__

#include <inttypes.h>
#include <cryptopp/dsa.h>
#include <cryptopp/asn.h>
#include <cryptopp/oids.h>
#include <cryptopp/osrng.h>
#include <cryptopp/eccrypto.h>
#include "CryptoConst.h"

namespace i2p
{
namespace crypto
{
	class Verifier
	{
		public:
			
			virtual ~Verifier () {};
			virtual bool Verify (const uint8_t * buf, size_t len, const uint8_t * signature) const = 0;
			virtual size_t GetPublicKeyLen () const = 0;
			virtual size_t GetSignatureLen () const = 0;
	};

	class Signer
	{
		public:

			virtual ~Signer () {};		
			virtual void Sign (CryptoPP::RandomNumberGenerator& rnd, const uint8_t * buf, int len, uint8_t * signature) const = 0; 
	};

	const size_t DSA_PUBLIC_KEY_LENGTH = 128;
	const size_t DSA_SIGNATURE_L