// blake2.h - written and placed in the public domain by Jeffrey Walton
//            and Zooko Wilcox-O'Hearn. Based on Aumasson, Neves,
//            Wilcox-O'Hearn and Winnerlein's reference BLAKE2
//            implementation at http://github.com/BLAKE2/BLAKE2.

/// \file blake2.h
/// \brief Classes for BLAKE2b and BLAKE2s message digests and keyed message digests
/// \details This implementation follows Aumasson, Neves, Wilcox-O'Hearn and Winnerlein's
///   <A HREF="http://blake2.net/blake2.pdf">BLAKE2: simpler, smaller, fast as MD5</A> (2013.01.29).
///   Static algorithm name return either "BLAKE2b" or "BLAKE2s". An object algorithm name follows
///   the naming described in <A HREF="http://tools.ietf.org/html/rfc7693#section-4">RFC 7693, The
///   BLAKE2 Cryptographic Hash and Message Authentication Code (MAC)</A>.
/// \since C++ since Crypto++ 5.6.4, SSE since Crypto++ 5.6.4, NEON since Crypto++ 6.0,
///   Power8 since Crypto++ 8.0

#ifndef CRYPTOPP_BLAKE2_H
#define CRYPTOPP_BLAKE2_H

#include "cryptlib.h"
#include "secblock.h"
#include "seckey.h"

NAMESPACE_BEGIN(CryptoPP)

/// \brief BLAKE2s hash information
/// \since Crypto++ 5.6.4
struct BLAKE2s_Info : public VariableKeyLength<32,0,32,1,SimpleKeyingInterface::NOT_RESYNCHRONIZABLE>
{
    typedef VariableKeyLength<32,0,32,1,SimpleKeyingInterface::NOT_RESYNCHRONIZABLE> KeyBase;
    CRYPTOPP_CONSTANT(MIN_KEYLENGTH = KeyBase::MIN_KEYLENGTH)
    CRYPTOPP_CONSTANT(MAX_KEYLENGTH = KeyBase::MAX_KEYLENGTH)
    CRYPTOPP_CONSTANT(DEFAULT_KEYLENGTH = KeyBase::DEFAULT_KEYLENGTH)

    CRYPTOPP_CONSTANT(BLOCKSIZE = 64)
    CRYPTOPP_CONSTANT(DIGESTSIZE = 32)
    CRYPTOPP_CONSTANT(SALTSIZE = 8)
    CRYPTOPP_CONSTANT(PERSONALIZATIONSIZE = 8)

    CRYPTOPP_STATIC_CONSTEXPR const char* StaticAlgorithmName() {return "BLAKE2s";}
};

/// \brief BLAKE2b hash information
/// \since Crypto++ 5.6.4
struct BLAKE2b_Info : public VariableKeyLength<64,0,64,1,SimpleKeyingInterface::NOT_RESYNCHRONIZABLE>
{
    typedef VariableKeyLength<64,0,64,1,SimpleKeyingInterface::NOT_RESYNCHRONIZABLE> KeyBase;
    CRYPTOPP_CONSTANT(MIN_KEYLENGTH = KeyBase::MIN_KEYLENGTH)
    CRYPTOPP_CONSTANT(MAX_KEYLENGTH = KeyBase::MAX_KEYLENGTH)
    CRYPTOPP_CONSTANT(DEFAULT_KEYLENGTH = KeyBase::DEFAULT_KEYLENGTH)

    CRYPTOPP_CONSTANT(BLOCKSIZE = 128)
    CRYPTOPP_CONSTANT(DIGESTSIZE = 64)
    CRYPTOPP_CONSTANT(SALTSIZE = 16)
    CRYPTOPP_CONSTANT(PERSONALIZATIONSIZE = 16)

    CRYPTOPP_STATIC_CONSTEXPR const char* StaticAlgorithmName() {return "BLAKE2b";}
};

/// \brief BLAKE2s parameter block
struct CRYPTOPP_NO_VTABLE BLAKE2s_ParameterBlock
{
    CRYPTOPP_CONSTANT(SALTSIZE = BLAKE2s_Info::SALTSIZE)
    CRYPTOPP_CONSTANT(DIGESTSIZE = BLAKE2s_Info::DIGESTSIZE)
    CRYPTOPP_CONSTANT(PERSONALIZATIONSIZE = BLAKE2s_Info::PERSONALIZATIONSIZE)

    BLAKE2s_ParameterBlock()
    {
        Reset();
    }

    BLAKE2s_ParameterBlock(size_t digestSize)
    {
        Reset(digestSize);
    }

    BLAKE2s_ParameterBlock(size_t digestSize, size_t keyLength, const byte* salt, size_t saltLength,
        const byte* personalization, size_t personalizationLength);

    void Reset(size_t digestLength=DIGESTSIZE, size_t keyLength=0);

    byte* data() {
        return m_data.data();
    }

    const byte* data() const {
        return m_data.data();
    }

    size_t size() const {
        return m_data.size();
    }

    byte* salt() {
        return m_data + SaltOff;
    }

    byte* personalization() {
        return m_data + PersonalizationOff;
    }

    // Offsets into the byte array
    enum {
        DigestOff = 0, KeyOff = 1, FanoutOff = 2, DepthOff = 3, LeafOff = 4, NodeOff = 8,
        NodeDepthOff = 14, InnerOff = 15, SaltOff = 16, PersonalizationOff = 24
    };

    FixedSizeAlignedSecBlock<byte, 32, true> m_data;
};

/// \brief BLAKE2b parameter block
struct CRYPTOPP_NO_VTABLE BLAKE2b_ParameterBlock
{
    CRYPTOPP_CONSTANT(SALTSIZE = BLAKE2b_Info::SALTSIZE)
    CRYPTOPP_CONSTANT(DIGESTSIZE = BLAKE2b_Info::DIGESTSIZE)
    CRYPTOPP_CONSTANT(PERSONALIZATIONSIZE = BLAKE2b_Info::PERSONALIZATIONSIZE)

    BLAKE2b_ParameterBlock()
    {
        Reset();
    }

    BLAKE2b_ParameterBlock(size_t digestSize)
    {
        Reset(digestSize);
    }

    BLAKE2b_ParameterBlock(size_t digestSize, size_t keyLength, const byte* salt, size_t saltLength,
        const byte* personalization, size_t personalizationLength);

    void Reset(size_t digestLength=DIGESTSIZE, size_t keyLength=0);

    byte* data() {
        return m_data.data();
    }

    const byte* data() const {
        return m_data.data();
    }

    size_t size() const {
        return m_data.size();
    }

    byte* salt() {
        return m_data + SaltOff;
    }

    byte* personalization() {
        return m_data + PersonalizationOff;
    }

    // Offsets into the byte array
    enum {
        DigestOff = 0, KeyOff = 1, FanoutOff = 2, DepthOff = 3, LeafOff = 4, NodeOff = 8,
        NodeDepthOff = 16, InnerOff = 17, RfuOff = 18, SaltOff = 32, PersonalizationOff = 48
    };

    FixedSizeAlignedSecBlock<byte, 64, true> m_data;
};

/// \brief BLAKE2s state information
/// \since Crypto++ 5.6.4
struct CRYPTOPP_NO_VTABLE BLAKE2s_State
{
    BLAKE2s_State() {
        Reset();
    }

    void Reset();

    inline word32* h() {
        return m_hft.data();
    }

    inline word32* t() {
        return m_hft.data() + 8;
    }

    inline word32* f() {
        return m_hft.data() + 10;
    }

    inline byte* data() {
        return m_buf.data();
    }

    // SSE4, Power7 and NEON depend upon t[] and f[] being side-by-side
    CRYPTOPP_CONSTANT(BLOCKSIZE = BLAKE2s_Info::BLOCKSIZE)
    FixedSizeAlignedSecBlock<word32, 8+2+2, true> m_hft;
    FixedSizeAlignedSecBlock<byte, BLOCKSIZE, true> m_buf;
    size_t m_len;
};

/// \brief BLAKE2b state information
/// \since Crypto++ 5.6.4
struct CRYPTOPP_NO_VTABLE BLAKE2b_State
{
    BLAKE2b_State() {
        Reset();
    }

    void Reset();

    inline word64* h() {
        return m_hft.data();
    }

    inline word64* t() {
        return m_hft.data() + 8;
    }

    inline word64* f() {
        return m_hft.data() + 10;
    }

    inline byte* data() {
        return m_buf.data();
    }

    // SSE4, Power8 and NEON depend upon t[] and f[] being side-by-side
    CRYPTOPP_CONSTANT(BLOCKSIZE = BLAKE2b_Info::BLOCKSIZE)
    FixedSizeAlignedSecBlock<word64, 8+2+2, true> m_hft;
    FixedSizeAlignedSecBlock<byte, BLOCKSIZE, true> m_buf;
    size_t m_len;
};

/// \brief The BLAKE2s cryptographic hash function
/// \details BLAKE2s can function as both a hash and keyed hash. If you want only the hash,
///   then use the BLAKE2s constructor that accepts no parameters or digest size. If you
///   want a keyed hash, then use the constructor that accpts the key as a parameter.
///   Once a key and digest size are selected, its effectively immutable. The Restart()
///   method that accepts a ParameterBlock does not allow you to change it.
/// \sa Aumasson, Neves, Wilcox-O'Hearn and Winnerlein's
///   <A HREF="http://blake2.net/blake2.pdf">BLAKE2: simpler, smaller, fast as MD5</A> (2013.01.29).
/// \since C++ since Crypto++ 5.6.4, SSE since Crypto++ 5.6.4, NEON since Crypto++ 6.0,
///   Power8 since Crypto++ 8.0
class BLAKE2s : public SimpleKeyingInterfaceImpl<MessageAuthenticationCode, BLAKE2s_Info>
{
public:
    CRYPTOPP_CONSTANT(DEFAULT_KEYLENGTH = BLAKE2s_Info::DEFAULT_KEYLENGTH)
    CRYPTOPP_CONSTANT(MIN_KEYLENGTH = BLAKE2s_Info::MIN_KEYLENGTH)
    CRYPTOPP_CONSTANT(MAX_KEYLENGTH = BLAKE2s_Info::MAX_KEYLENGTH)

    CRYPTOPP_CONSTANT(DIGESTSIZE = BLAKE2s_Info::DIGESTSIZE)
    CRYPTOPP_CONSTANT(BLOCKSIZE = BLAKE2s_Info::BLOCKSIZE)
    CRYPTOPP_CONSTANT(SALTSIZE = BLAKE2s_Info::SALTSIZE)
    CRYPTOPP_CONSTANT(PERSONALIZATIONSIZE = BLAKE2s_Info::PERSONALIZATIONSIZE)

    typedef BLAKE2s_State State;
    typedef BLAKE2s_ParameterBlock ParameterBlock;

    CRYPTOPP_STATIC_CONSTEXPR const char* StaticAlgorithmName() {return "BLAKE2s";}

    virtual ~BLAKE2s() {}

    /// \brief Construct a BLAKE2s hash
    /// \param digestSize the digest size, in bytes
    /// \param treeMode flag indicating tree mode
    BLAKE2s(bool treeMode=false, unsigned int digestSize = DIGESTSIZE);

    /// \brief Construct a BLAKE2s hash
    /// \param key a byte array used to key the cipher
    /// \param keyLength the size of the byte array
    /// \param salt a byte array used as salt
    /// \param saltLength the size of the byte array
    /// \param personalization a byte array used as prsonalization string
    /// \param personalizationLength the size of the byte array
    /// \param treeMode flag indicating tree mode
    /// \param digestSize the digest size, in bytes
    BLAKE2s(const byte *key, size_t keyLength, const byte* salt = NULLPTR, size_t saltLength = 0,
        const byte* personalization = NULLPTR, size_t personalizationLength = 0,
        bool treeMode=false, unsigned int digestSize = DIGESTSIZE);

    /// \brief Retrieve the object's name
    /// \returns the object's algorithm name following RFC 7693
    /// \details Object algorithm name follows the naming described in
    ///   <A HREF="http://tools.ietf.org/html/rfc7693#section-4">RFC 7693, The BLAKE2 Cryptographic Hash and
    /// Message Authentication Code (MAC)</A>. For example, "BLAKE2b-512" and "BLAKE2s-256".
    std::string AlgorithmName() const {return std::string(BLAKE2s_Info::StaticAlgorithmName()) + "-" + IntToString(DigestSize()*8);}

    unsigned int DigestSize() const {return m_digestSize;}
    unsigned int OptimalDataAlignment() const;

    void Update(const byte *input, size_t length);
    void Restart();

    /// \brief Restart a hash with parameter block and counter
    /// \param block parameter block
    /// \param counter counter array
    /// \details Parameter block is persisted across calls to Restart().
    void Restart(const BLAKE2s_ParameterBlock& block, const word32 counter[2]);

    /// \brief Set tree mode
    /// \param mode the new tree mode
    /// \details BLAKE2 has two finalization flags, called State::f[0] and State::f[1].
    ///   If <tt>treeMode=false</tt> (default), then State::f[1] is never set. If
    ///   <tt>treeMode=true</tt>, then State::f[1] is set when State::f[0] is set.
    ///   Tree mode is persisted across calls to Restart().
    void SetTreeMode(bool mode) {m_treeMode=mode;}

    /// \brief Get tree mode
    /// \returns the current tree mode
    /// \details Tree mode is persisted across calls to Restart().
    bool GetTreeMode() const {return m_treeMode;}

    void TruncatedFinal(byte *hash, size_t size);

    std::string AlgorithmProvider() const;

protected:
    // Operates on state buffer and/or input. Must be BLOCKSIZE, final block will pad with 0's.
    void Compress(const byte *input);
    inline void IncrementCounter(size_t count=BLOCKSIZE);

    void UncheckedSetKey(const byte* key, unsigned int length, const CryptoPP::NameValuePairs& params);

private:
    State m_state;
    ParameterBlock m_block;
    AlignedSecByteBlock m_key;
    word32 m_digestSize, m_keyLength;
    bool m_treeMode;
};

/// \brief The BLAKE2b cryptographic hash function
/// \details BLAKE2b can function as both a hash and keyed hash. If you want only the hash,
///   then use the BLAKE2b constructor that accepts no parameters or digest size. If you
///   want a keyed hash, then use the constructor that accpts the key as a parameter.
///   Once a key and digest size are selected, its effectively immutable. The Restart()
///   method that accepts a ParameterBlock does not allow you to change it.
/// \sa Aumasson, Neves, Wilcox-O'Hearn and Winnerlein's
///   <A HREF="http://blake2.net/blake2.pdf">BLAKE2: simpler, smaller, fast as MD5</A> (2013.01.29).
/// \since C++ since Crypto++ 5.6.4, SSE since Crypto++ 5.6.4, NEON since Crypto++ 6.0,
///   Power8 since Crypto++ 8.0
class BLAKE2b : public SimpleKeyingInterfaceImpl<MessageAuthenticationCode, BLAKE2b_Info>
{
public:
    CRYPTOPP_CONSTANT(DEFAULT_KEYLENGTH = BLAKE2b_Info::DEFAULT_KEYLENGTH)
    CRYPTOPP_CONSTANT(MIN_KEYLENGTH = BLAKE2b_Info::MIN_KEYLENGTH)
    CRYPTOPP_CONSTANT(MAX_KEYLENGTH = BLAKE2b_Info::MAX_KEYLENGTH)

    CRYPTOPP_CONSTANT(DIGESTSIZE = BLAKE2b_Info::DIGESTSIZE)
    CRYPTOPP_CONSTANT(BLOCKSIZE = BLAKE2b_Info::BLOCKSIZE)
    CRYPTOPP_CONSTANT(SALTSIZE = BLAKE2b_Info::SALTSIZE)
    CRYPTOPP_CONSTANT(PERSONALIZATIONSIZE = BLAKE2b_Info::PERSONALIZATIONSIZE)

    typedef BLAKE2b_State State;
    typedef BLAKE2b_ParameterBlock ParameterBlock;

    CRYPTOPP_STATIC_CONSTEXPR const char* StaticAlgorithmName() {return "BLAKE2b";}

    virtual ~BLAKE2b() {}

    /// \brief Construct a BLAKE2b hash
    /// \param digestSize the digest size, in bytes
    /// \param treeMode flag indicating tree mode
    BLAKE2b(bool treeMode=false, unsigned int digestSize = DIGESTSIZE);

    /// \brief Construct a BLAKE2b hash
    /// \param key a byte array used to key the cipher
    /// \param keyLength the size of the byte array
    /// \param salt a byte array used as salt
    /// \param saltLength the size of the byte array
    /// \param personalization a byte array used as prsonalization string
    /// \param personalizationLength the size of the byte array
    /// \param treeMode flag indicating tree mode
    /// \param digestSize the digest size, in bytes
    BLAKE2b(const byte *key, size_t keyLength, const byte* salt = NULLPTR, size_t saltLength = 0,
        const byte* personalization = NULLPTR, size_t personalizationLength = 0,
        bool treeMode=false, unsigned int digestSize = DIGESTSIZE);

    /// \brief Retrieve the object's name
    /// \returns the object's algorithm name following RFC 7693
    /// \details Object algorithm name follows the naming described in
    ///   <A HREF="http://tools.ietf.org/html/rfc7693#section-4">RFC 7693, The BLAKE2 Cryptographic Hash and
    /// Message Authentication Code (MAC)</A>. For example, "BLAKE2b-512" and "BLAKE2s-256".
    std::string AlgorithmName() const {return std::string(BLAKE2b_Info::StaticAlgorithmName()) + "-" + IntToString(DigestSize()*8);}

    unsigned int DigestSize() const {return m_digestSize;}
    unsigned int OptimalDataAlignment() const;

    void Update(const byte *input, size_t length);
    void Restart();

    /// \brief Restart a hash with parameter block and counter
    /// \param block parameter block
    /// \param counter counter array
    /// \details Parameter block is persisted across calls to Restart().
    void Restart(const BLAKE2b_ParameterBlock& block, const word64 counter[2]);

    /// \brief Set tree mode
    /// \param mode the new tree mode
    /// \details BLAKE2 has two finalization flags, called State::f[0] and State::f[1].
    ///   If <tt>treeMode=false</tt> (default), then State::f[1] is never set. If
    ///   <tt>treeMode=true</tt>, then State::f[1] is set when State::f[0] is set.
    ///   Tree mode is persisted across calls to Restart().
    void SetTreeMode(bool mode) {m_treeMode=mode;}

    /// \brief Get tree mode
    /// \returns the current tree mode
    /// \details Tree mode is persisted across calls to Restart().
    bool GetTreeMode() const {return m_treeMode;}

    void TruncatedFinal(byte *hash, size_t size);

    std::string AlgorithmProvider() const;

protected:

    // Operates on state buffer and/or input. Must be BLOCKSIZE, final block will pad with 0's.
    void Compress(const byte *input);
    inline void IncrementCounter(size_t count=BLOCKSIZE);

    void UncheckedSetKey(const byte* key, unsigned int length, const CryptoPP::NameValuePairs& params);

private:
    State m_state;
    ParameterBlock m_block;
    AlignedSecByteBlock m_key;
    word32 m_digestSize, m_keyLength;
    bool m_treeMode;
};

NAMESPACE_END

#endif
