SHA_384.hpp

#ifndef _SNARKFRONT_SHA_384_HPP_
#define _SNARKFRONT_SHA_384_HPP_

#include <array>
#include <cstdint>
#include "Alg.hpp"
#include "Alg_uint.hpp"
#include "AST.hpp"
#include "BitwiseOps.hpp"
#include "Lazy.hpp"
#include "SHA_512.hpp"

namespace snarkfront {

////////////////////////////////////////////////////////////////////////////////
// SHA-384
//

template <typename T, typename MSG, typename F>
class SHA_384 : public SHA_512<T, MSG, F>
{
public:
    typedef T WordType;
    typedef std::array<T, 16> MsgType;
    typedef std::array<T, 6> DigType;

    SHA_384()
        : m_setDigest(false)
    {}

    // overrides base class SHA-512
    const std::array<T, 6>& digest() {
        if (m_setDigest) {
            for (std::size_t i = 0; i < 6; ++i) {
                m_Hleft384[i] = this->m_H[i];
            }

            m_setDigest = false;
        }

        return m_Hleft384;
    }

    // overrides base class SHA-512
    virtual void initHashValue() {
        // set initial hash value (NIST FIPS 180-4 section 5.3.4)
        const std::array<uint64_t, 8> a {
            0xcbbb9d5dc1059ed8, 0x629a292a367cd507,
            0x9159015a3070dd17, 0x152fecd8f70e5939,

            0x67332667ffc00b31, 0x8eb44a8768581511,
            0xdb0c2e0d64f98fa7, 0x47b5481dbefa4fa4 };

        for (std::size_t i = 0; i < 8; ++i) {
            this->m_H[i] = F::constant(a[i]);
        }
    }

    virtual void afterHash() {
        m_setDigest = true;
    }

private:
    // truncated 384-bit message digest
    std::array<T, 6> m_Hleft384;

    bool m_setDigest;
};

////////////////////////////////////////////////////////////////////////////////
// typedefs
//

namespace zk {
    template <typename FR> using
    SHA384 = SHA_384<AST_Var<Alg_uint64<FR>>,
                     Lazy<AST_Var<Alg_uint64<FR>>, std::uint64_t>,
                     SHA_Functions<AST_Node<Alg_uint64<FR>>,
                                   AST_Op<Alg_uint64<FR>>,
                                   BitwiseAST<Alg_uint64<FR>, Alg_uint64<FR>>>>;
} // namespace zk

namespace eval {
typedef SHA_384<std::uint64_t,
                std::uint64_t,
                SHA_Functions<std::uint64_t,
                              std::uint64_t,
                              BitwiseINT<std::uint64_t, std::uint64_t>>>
    SHA384;
} // namespace eval

} // namespace snarkfront

#endif