/ libi2pd / Identity.h
Identity.h
  1  /*
  2  * Copyright (c) 2013-2026, The PurpleI2P Project
  3  *
  4  * This file is part of Purple i2pd project and licensed under BSD3
  5  *
  6  * See full license text in LICENSE file at top of project tree
  7  */
  8  
  9  #ifndef IDENTITY_H__
 10  #define IDENTITY_H__
 11  
 12  #include <inttypes.h>
 13  #include <string.h>
 14  #include <string>
 15  #include <string_view>
 16  #include <memory>
 17  #include <vector>
 18  #include "Base.h"
 19  #include "Signature.h"
 20  
 21  namespace i2p
 22  {
 23  namespace crypto
 24  {
 25  	class CryptoKeyEncryptor;
 26  	class CryptoKeyDecryptor;
 27  }
 28  namespace data
 29  {
 30  	typedef Tag<32> IdentHash;
 31  	inline std::string GetIdentHashAbbreviation (const IdentHash& ident)
 32  	{
 33  		return ident.ToBase64 ().substr (0, 4);
 34  	}
 35  
 36  	std::vector<IdentHash> ExtractIdentHashes (std::string_view hashes);
 37  
 38  	struct Keys
 39  	{
 40  		uint8_t privateKey[256];
 41  		uint8_t signingPrivateKey[20];
 42  		uint8_t publicKey[256];
 43  		uint8_t signingKey[128];
 44  	};
 45  
 46  	const uint8_t CERTIFICATE_TYPE_NULL = 0;
 47  	const uint8_t CERTIFICATE_TYPE_HASHCASH = 1;
 48  	const uint8_t CERTIFICATE_TYPE_HIDDEN = 2;
 49  	const uint8_t CERTIFICATE_TYPE_SIGNED = 3;
 50  	const uint8_t CERTIFICATE_TYPE_MULTIPLE = 4;
 51  	const uint8_t CERTIFICATE_TYPE_KEY = 5;
 52  
 53  	struct Identity
 54  	{
 55  		uint8_t publicKey[256];
 56  		uint8_t signingKey[128];
 57  		uint8_t certificate[3];	// byte 1 - type, bytes 2-3 - length
 58  
 59  		Identity () = default;
 60  		Identity (const Keys& keys) { *this = keys; };
 61  		Identity& operator=(const Keys& keys);
 62  		size_t FromBuffer (const uint8_t * buf, size_t len);
 63  		IdentHash Hash () const;
 64  		operator uint8_t * () { return reinterpret_cast<uint8_t *>(this); }
 65  		operator const uint8_t * () const { return reinterpret_cast<const uint8_t *>(this); }
 66  	};
 67  
 68  	Keys CreateRandomKeys ();
 69  
 70  	const size_t DEFAULT_IDENTITY_SIZE = sizeof (Identity); // 387 bytes
 71  
 72  	const uint16_t CRYPTO_KEY_TYPE_ELGAMAL = 0;
 73  	const uint16_t CRYPTO_KEY_TYPE_ECIES_P256_SHA256_AES256CBC = 1;
 74  	const uint16_t CRYPTO_KEY_TYPE_ECIES_X25519_AEAD = 4;
 75  	const uint16_t CRYPTO_KEY_TYPE_ECIES_MLKEM512_X25519_AEAD = 5;
 76  	const uint16_t CRYPTO_KEY_TYPE_ECIES_MLKEM768_X25519_AEAD = 6;
 77  	const uint16_t CRYPTO_KEY_TYPE_ECIES_MLKEM1024_X25519_AEAD = 7;
 78  
 79  	const uint16_t SIGNING_KEY_TYPE_DSA_SHA1 = 0;
 80  	const uint16_t SIGNING_KEY_TYPE_ECDSA_SHA256_P256 = 1;
 81  	const uint16_t SIGNING_KEY_TYPE_ECDSA_SHA384_P384 = 2;
 82  	const uint16_t SIGNING_KEY_TYPE_ECDSA_SHA512_P521 = 3;
 83  	const uint16_t SIGNING_KEY_TYPE_RSA_SHA256_2048 = 4;
 84  	const uint16_t SIGNING_KEY_TYPE_RSA_SHA384_3072 = 5;
 85  	const uint16_t SIGNING_KEY_TYPE_RSA_SHA512_4096 = 6;
 86  	const uint16_t SIGNING_KEY_TYPE_EDDSA_SHA512_ED25519 = 7;
 87  	const uint16_t SIGNING_KEY_TYPE_EDDSA_SHA512_ED25519ph = 8; // since openssl 3.0.0
 88  	const uint16_t SIGNING_KEY_TYPE_GOSTR3410_CRYPTO_PRO_A_GOSTR3411_256 = 9;
 89  	const uint16_t SIGNING_KEY_TYPE_GOSTR3410_TC26_A_512_GOSTR3411_512 = 10; // approved by FSB
 90  	const uint16_t SIGNING_KEY_TYPE_REDDSA_SHA512_ED25519 = 11; // for LeaseSet2 only
 91  	const uint16_t SIGNING_KEY_TYPE_MLDSA44 = 12;
 92  
 93  	typedef uint16_t SigningKeyType;
 94  	typedef uint16_t CryptoKeyType;
 95  
 96  	const size_t MAX_EXTENDED_BUFFER_SIZE = 8; // cryptoKeyType + signingKeyType + 4 extra bytes of P521
 97  	class IdentityEx
 98  	{
 99  		public:
100  
101  			IdentityEx ();
102  			IdentityEx (const uint8_t * publicKey, const uint8_t * signingKey,
103  				SigningKeyType type = SIGNING_KEY_TYPE_DSA_SHA1, CryptoKeyType cryptoType = CRYPTO_KEY_TYPE_ELGAMAL);
104  			IdentityEx (const uint8_t * buf, size_t len);
105  			IdentityEx (const IdentityEx& other);
106  			IdentityEx (const Identity& standard);
107  			~IdentityEx ();
108  			IdentityEx& operator=(const IdentityEx& other);
109  			IdentityEx& operator=(const Identity& standard);
110  
111  			size_t FromBuffer (const uint8_t * buf, size_t len);
112  			size_t ToBuffer (uint8_t * buf, size_t len) const;
113  			size_t FromBase64(std::string_view s);
114  			std::string ToBase64 () const;
115  			const Identity& GetStandardIdentity () const { return m_StandardIdentity; };
116  
117  			const IdentHash& GetIdentHash () const { return m_IdentHash; };
118  			const uint8_t * GetEncryptionPublicKey () const { return m_StandardIdentity.publicKey; };
119  			uint8_t * GetEncryptionPublicKeyBuffer () { return m_StandardIdentity.publicKey; };
120  			std::shared_ptr<i2p::crypto::CryptoKeyEncryptor> CreateEncryptor (const uint8_t * key) const;
121  			size_t GetFullLen () const { return m_ExtendedLen + DEFAULT_IDENTITY_SIZE; };
122  			size_t GetSigningPublicKeyLen () const;
123  			const uint8_t * GetSigningPublicKeyBuffer () const; // returns NULL for P521
124  			size_t GetSigningPrivateKeyLen () const;
125  			size_t GetSignatureLen () const;
126  			bool Verify (const uint8_t * buf, size_t len, const uint8_t * signature) const;
127  			SigningKeyType GetSigningKeyType () const;
128  			bool IsRSA () const; // signing key type
129  			CryptoKeyType GetCryptoKeyType () const;
130  
131  			bool operator == (const IdentityEx & other) const { return GetIdentHash() == other.GetIdentHash(); }
132  			void RecalculateIdentHash(uint8_t * buff=nullptr);
133  
134  			static i2p::crypto::Verifier * CreateVerifier (SigningKeyType keyType);
135  			static std::shared_ptr<i2p::crypto::CryptoKeyEncryptor> CreateEncryptor (CryptoKeyType keyType, const uint8_t * key);
136  
137  		private:
138  
139  			void CreateVerifier ();
140  
141  		private:
142  
143  			Identity m_StandardIdentity;
144  			IdentHash m_IdentHash;
145  			std::unique_ptr<i2p::crypto::Verifier> m_Verifier;
146  			size_t m_ExtendedLen;
147  			union
148  			{
149  				uint8_t m_ExtendedBuffer[MAX_EXTENDED_BUFFER_SIZE];
150  				uint8_t * m_ExtendedBufferPtr;
151  			};
152  	};
153  
154  	size_t GetIdentityBufferLen (const uint8_t * buf, size_t len); // return actual identity length in buffer
155  
156  	class PrivateKeys // for eepsites
157  	{
158  		public:
159  
160  			PrivateKeys () = default;
161  			PrivateKeys (const PrivateKeys& other) { *this = other; };
162  			PrivateKeys (const Keys& keys) { *this = keys; };
163  			PrivateKeys& operator=(const Keys& keys);
164  			PrivateKeys& operator=(const PrivateKeys& other);
165  			~PrivateKeys () = default;
166  
167  			std::shared_ptr<const IdentityEx> GetPublic () const { return m_Public; };
168  			const uint8_t * GetPrivateKey () const { return m_PrivateKey; };
169  			const uint8_t * GetSigningPrivateKey () const { return m_SigningPrivateKey.data (); };
170  			size_t GetSignatureLen () const; // might not match identity
171  			bool IsOfflineSignature () const { return m_TransientSignatureLen > 0; };
172  			uint8_t * GetPadding();
173  			void RecalculateIdentHash(uint8_t * buf=nullptr) { m_Public->RecalculateIdentHash(buf); }
174  			void Sign (const uint8_t * buf, int len, uint8_t * signature) const;
175  
176  			size_t GetFullLen () const;
177  			size_t FromBuffer (const uint8_t * buf, size_t len);
178  			size_t ToBuffer (uint8_t * buf, size_t len) const;
179  
180  			size_t FromBase64(std::string_view s);
181  			std::string ToBase64 () const;
182  
183  			std::shared_ptr<i2p::crypto::CryptoKeyDecryptor> CreateDecryptor (const uint8_t * key) const;
184  
185  			static std::shared_ptr<i2p::crypto::CryptoKeyDecryptor> CreateDecryptor (CryptoKeyType cryptoType, const uint8_t * key);
186  			static PrivateKeys CreateRandomKeys (SigningKeyType type = SIGNING_KEY_TYPE_DSA_SHA1, CryptoKeyType cryptoType = CRYPTO_KEY_TYPE_ELGAMAL, bool isDestination = false);
187  			static void GenerateSigningKeyPair (SigningKeyType type, uint8_t * priv, uint8_t * pub);
188  			static void GenerateCryptoKeyPair (CryptoKeyType type, uint8_t * priv, uint8_t * pub); // priv and pub are 256 bytes long
189  			static i2p::crypto::Signer * CreateSigner (SigningKeyType keyType, const uint8_t * priv);
190  
191  			// offline keys
192  			PrivateKeys CreateOfflineKeys (SigningKeyType type, uint32_t expires) const;
193  			const std::vector<uint8_t>& GetOfflineSignature () const { return m_OfflineSignature; };
194  
195  		private:
196  
197  			void CreateSigner () const;
198  			void CreateSigner (SigningKeyType keyType) const;
199  			size_t GetPrivateKeyLen () const;
200  
201  		private:
202  
203  			std::shared_ptr<IdentityEx> m_Public;
204  			uint8_t m_PrivateKey[256];
205  			std::vector<uint8_t> m_SigningPrivateKey;
206  			mutable std::unique_ptr<i2p::crypto::Signer> m_Signer;
207  			std::vector<uint8_t> m_OfflineSignature; // non zero length, if applicable
208  			size_t m_TransientSignatureLen = 0;
209  			size_t m_TransientSigningPrivateKeyLen = 0;
210  	};
211  
212  	// kademlia
213  	struct XORMetric
214  	{
215  		union
216  		{
217  			uint8_t metric[32];
218  			uint64_t metric_ll[4];
219  		};
220  
221  		void SetMin () { memset (metric, 0, 32); };
222  		void SetMax () { memset (metric, 0xFF, 32); };
223  		bool operator< (const XORMetric& other) const { return memcmp (metric, other.metric, 32) < 0; };
224  	};
225  
226  	IdentHash CreateRoutingKey (const IdentHash& ident, bool nextDay = false);
227  	XORMetric operator^(const IdentHash& key1, const IdentHash& key2);
228  
229  	// destination for delivery instructions
230  	class RoutingDestination
231  	{
232  		public:
233  
234  			RoutingDestination () {};
235  			virtual ~RoutingDestination () {};
236  
237  			virtual std::shared_ptr<const IdentityEx> GetIdentity () const = 0;
238  			virtual void Encrypt (const uint8_t * data, uint8_t * encrypted) const = 0; // encrypt data for
239  			virtual bool IsDestination () const = 0; // for garlic
240  
241  			const IdentHash& GetIdentHash () const { return GetIdentity ()->GetIdentHash (); };
242  			virtual CryptoKeyType GetEncryptionType () const { return GetIdentity ()->GetCryptoKeyType (); }; // override in LeaseSet2
243  	};
244  
245  	class LocalDestination
246  	{
247  		public:
248  
249  			virtual ~LocalDestination() {};
250  			virtual bool Decrypt (const uint8_t * encrypted, uint8_t * data, CryptoKeyType preferredCrypto = CRYPTO_KEY_TYPE_ELGAMAL) const = 0;
251  			virtual std::shared_ptr<const IdentityEx> GetIdentity () const = 0;
252  
253  			const IdentHash& GetIdentHash () const { return GetIdentity ()->GetIdentHash (); };
254  			virtual bool SupportsEncryptionType (CryptoKeyType keyType) const { return GetIdentity ()->GetCryptoKeyType () == keyType; }; // override for LeaseSet
255  			virtual const uint8_t * GetEncryptionPublicKey (CryptoKeyType keyType) const { return GetIdentity ()->GetEncryptionPublicKey (); }; // override for LeaseSet
256  	};
257  }
258  }
259  
260  #endif