i2pd/Crypto.h
2015-11-03 09:15:49 -05:00

322 lines
6.5 KiB
C++

#ifndef CRYPTO_H__
#define CRYPTO_H__
#include <inttypes.h>
#include <string>
#include <openssl/bn.h>
#include <openssl/dh.h>
#include <openssl/aes.h>
#include "Base.h"
namespace i2p
{
namespace crypto
{
struct CryptoConstants
{
// DH/ElGamal
BIGNUM * elgp;
BIGNUM * elgg;
// DSA
BIGNUM * dsap;
BIGNUM * dsaq;
BIGNUM * dsag;
// RSA
BIGNUM * rsae;
CryptoConstants (const uint8_t * elgp_, int elgg_, const uint8_t * dsap_,
const uint8_t * dsaq_, const uint8_t * dsag_, int rsae_)
{
elgp = BN_new ();
BN_bin2bn (elgp_, 256, elgp);
elgg = BN_new ();
BN_set_word (elgg, elgg_);
dsap = BN_new ();
BN_bin2bn (dsap_, 128, dsap);
dsaq = BN_new ();
BN_bin2bn (dsaq_, 20, dsaq);
dsag = BN_new ();
BN_bin2bn (dsag_, 128, dsag);
rsae = BN_new ();
BN_set_word (rsae, rsae_);
}
~CryptoConstants ()
{
BN_free (elgp); BN_free (elgg); BN_free (dsap); BN_free (dsaq); BN_free (dsag); BN_free (rsae);
}
};
const CryptoConstants& GetCryptoConstants ();
// DH/ElGamal
#define elgp GetCryptoConstants ().elgp
#define elgg GetCryptoConstants ().elgg
// DSA
#define dsap GetCryptoConstants ().dsap
#define dsaq GetCryptoConstants ().dsaq
#define dsag GetCryptoConstants ().dsag
// RSA
#define rsae GetCryptoConstants ().rsae
bool bn2buf (const BIGNUM * bn, uint8_t * buf, size_t len);
// DH
class DHKeys
{
public:
DHKeys ();
~DHKeys ();
void GenerateKeys (uint8_t * priv = nullptr, uint8_t * pub = nullptr);
const uint8_t * GetPublicKey ();
void Agree (const uint8_t * pub, uint8_t * shared);
private:
DH * m_DH;
uint8_t m_PublicKey[256];
bool m_IsUpdated;
};
// ElGamal
class ElGamalEncryption
{
public:
ElGamalEncryption (const uint8_t * key);
~ElGamalEncryption ();
void Encrypt (const uint8_t * data, int len, uint8_t * encrypted, bool zeroPadding = false) const;
private:
BN_CTX * ctx;
BIGNUM * a, * b1;
};
bool ElGamalDecrypt (const uint8_t * key, const uint8_t * encrypted, uint8_t * data, bool zeroPadding = false);
void GenerateElGamalKeyPair (uint8_t * priv, uint8_t * pub);
// HMAC
typedef i2p::data::Tag<32> MACKey;
void HMACMD5Digest (uint8_t * msg, size_t len, const MACKey& key, uint8_t * digest);
// AES
struct ChipherBlock
{
uint8_t buf[16];
void operator^=(const ChipherBlock& other) // XOR
{
#if defined(__x86_64__) // for Intel x64
__asm__
(
"movups (%[buf]), %%xmm0 \n"
"movups (%[other]), %%xmm1 \n"
"pxor %%xmm1, %%xmm0 \n"
"movups %%xmm0, (%[buf]) \n"
:
: [buf]"r"(buf), [other]"r"(other.buf)
: "%xmm0", "%xmm1", "memory"
);
#else
// TODO: implement it better
for (int i = 0; i < 16; i++)
buf[i] ^= other.buf[i];
#endif
}
};
typedef i2p::data::Tag<32> AESKey;
template<size_t sz>
class AESAlignedBuffer // 16 bytes alignment
{
public:
AESAlignedBuffer ()
{
m_Buf = m_UnalignedBuffer;
uint8_t rem = ((size_t)m_Buf) & 0x0f;
if (rem)
m_Buf += (16 - rem);
}
operator uint8_t * () { return m_Buf; };
operator const uint8_t * () const { return m_Buf; };
private:
uint8_t m_UnalignedBuffer[sz + 15]; // up to 15 bytes alignment
uint8_t * m_Buf;
};
#ifdef AESNI
class ECBCryptoAESNI
{
public:
uint8_t * GetKeySchedule () { return m_KeySchedule; };
protected:
void ExpandKey (const AESKey& key);
private:
AESAlignedBuffer<240> m_KeySchedule; // 14 rounds for AES-256, 240 bytes
};
class ECBEncryptionAESNI: public ECBCryptoAESNI
{
public:
void SetKey (const AESKey& key) { ExpandKey (key); };
void Encrypt (const ChipherBlock * in, ChipherBlock * out);
};
class ECBDecryptionAESNI: public ECBCryptoAESNI
{
public:
void SetKey (const AESKey& key);
void Decrypt (const ChipherBlock * in, ChipherBlock * out);
};
typedef ECBEncryptionAESNI ECBEncryption;
typedef ECBDecryptionAESNI ECBDecryption;
#else // use openssl
class ECBEncryption
{
public:
void SetKey (const AESKey& key)
{
AES_set_encrypt_key (key, 256, &m_Key);
}
void Encrypt (const ChipherBlock * in, ChipherBlock * out)
{
AES_encrypt (in->buf, out->buf, &m_Key);
}
private:
AES_KEY m_Key;
};
class ECBDecryption
{
public:
void SetKey (const AESKey& key)
{
AES_set_decrypt_key (key, 256, &m_Key);
}
void Decrypt (const ChipherBlock * in, ChipherBlock * out)
{
AES_decrypt (in->buf, out->buf, &m_Key);
}
private:
AES_KEY m_Key;
};
#endif
class CBCEncryption
{
public:
CBCEncryption () { memset (m_LastBlock.buf, 0, 16); };
void SetKey (const AESKey& key) { m_ECBEncryption.SetKey (key); }; // 32 bytes
void SetIV (const uint8_t * iv) { memcpy (m_LastBlock.buf, iv, 16); }; // 16 bytes
void Encrypt (int numBlocks, const ChipherBlock * in, ChipherBlock * out);
void Encrypt (const uint8_t * in, std::size_t len, uint8_t * out);
void Encrypt (const uint8_t * in, uint8_t * out); // one block
private:
ChipherBlock m_LastBlock;
ECBEncryption m_ECBEncryption;
};
class CBCDecryption
{
public:
CBCDecryption () { memset (m_IV.buf, 0, 16); };
void SetKey (const AESKey& key) { m_ECBDecryption.SetKey (key); }; // 32 bytes
void SetIV (const uint8_t * iv) { memcpy (m_IV.buf, iv, 16); }; // 16 bytes
void Decrypt (int numBlocks, const ChipherBlock * in, ChipherBlock * out);
void Decrypt (const uint8_t * in, std::size_t len, uint8_t * out);
void Decrypt (const uint8_t * in, uint8_t * out); // one block
private:
ChipherBlock m_IV;
ECBDecryption m_ECBDecryption;
};
class TunnelEncryption // with double IV encryption
{
public:
void SetKeys (const AESKey& layerKey, const AESKey& ivKey)
{
m_LayerEncryption.SetKey (layerKey);
m_IVEncryption.SetKey (ivKey);
}
void Encrypt (const uint8_t * in, uint8_t * out); // 1024 bytes (16 IV + 1008 data)
private:
ECBEncryption m_IVEncryption;
#ifdef AESNI
ECBEncryption m_LayerEncryption;
#else
CBCEncryption m_LayerEncryption;
#endif
};
class TunnelDecryption // with double IV encryption
{
public:
void SetKeys (const AESKey& layerKey, const AESKey& ivKey)
{
m_LayerDecryption.SetKey (layerKey);
m_IVDecryption.SetKey (ivKey);
}
void Decrypt (const uint8_t * in, uint8_t * out); // 1024 bytes (16 IV + 1008 data)
private:
ECBDecryption m_IVDecryption;
#ifdef AESNI
ECBDecryption m_LayerDecryption;
#else
CBCDecryption m_LayerDecryption;
#endif
};
}
}
#endif