digest.h

//------------------------------------------------------------------------------
/*
    This file is part of rippled: https://github.com/ripple/rippled
    Copyright (c) 2012, 2013 Ripple Labs Inc.
 
    Permission to use, copy, modify, and/or distribute this software for any
    purpose  with  or without fee is hereby granted, provided that the above
    copyright notice and this permission notice appear in all copies.
 
    THE  SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
    WITH  REGARD  TO  THIS  SOFTWARE  INCLUDING  ALL  IMPLIED  WARRANTIES  OF
    MERCHANTABILITY  AND  FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
    ANY  SPECIAL ,  DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
    WHATSOEVER  RESULTING  FROM  LOSS  OF USE, DATA OR PROFITS, WHETHER IN AN
    ACTION  OF  CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
//==============================================================================
 
#ifndef RIPPLE_PROTOCOL_DIGEST_H_INCLUDED
#define RIPPLE_PROTOCOL_DIGEST_H_INCLUDED
 
#include <xrpl/basics/base_uint.h>
#include <xrpl/crypto/secure_erase.h>
#include <boost/endian/conversion.hpp>
#include <algorithm>
#include <array>
 
namespace ripple {
 
//------------------------------------------------------------------------------
 
struct openssl_ripemd160_hasher
{
public:
    static constexpr auto const endian = boost::endian::order::native;
 
    using result_type = std::array<std::uint8_t, 20>;
 
    openssl_ripemd160_hasher();
 
    void
    operator()(void const* data, std::size_t size) noexcept;
 
    explicit
    operator result_type() noexcept;
 
private:
    char ctx_[96];
};
 
struct openssl_sha512_hasher
{
public:
    static constexpr auto const endian = boost::endian::order::native;
 
    using result_type = std::array<std::uint8_t, 64>;
 
    openssl_sha512_hasher();
 
    void
    operator()(void const* data, std::size_t size) noexcept;
 
    explicit
    operator result_type() noexcept;
 
private:
    char ctx_[216];
};
 
struct openssl_sha256_hasher
{
public:
    static constexpr auto const endian = boost::endian::order::native;
 
    using result_type = std::array<std::uint8_t, 32>;
 
    openssl_sha256_hasher();
 
    void
    operator()(void const* data, std::size_t size) noexcept;
 
    explicit
    operator result_type() noexcept;
 
private:
    char ctx_[112];
};
 
//------------------------------------------------------------------------------
 
using ripemd160_hasher = openssl_ripemd160_hasher;
using sha256_hasher = openssl_sha256_hasher;
using sha512_hasher = openssl_sha512_hasher;
 
//------------------------------------------------------------------------------
 
struct ripesha_hasher
{
private:
    sha256_hasher h_;
 
public:
    static constexpr auto const endian = boost::endian::order::native;
 
    using result_type = std::array<std::uint8_t, 20>;
 
    void
    operator()(void const* data, std::size_t size) noexcept
    {
        h_(data, size);
    }
 
    explicit
    operator result_type() noexcept
    {
        auto const d0 = sha256_hasher::result_type(h_);
        ripemd160_hasher rh;
        rh(d0.data(), d0.size());
        return ripemd160_hasher::result_type(rh);
    }
};
 
//------------------------------------------------------------------------------
 
namespace detail {
 
template <bool Secure>
struct basic_sha512_half_hasher
{
private:
    sha512_hasher h_;
 
public:
    static constexpr auto const endian = boost::endian::order::big;
 
    using result_type = uint256;
 
    ~basic_sha512_half_hasher()
    {
        erase(std::integral_constant<bool, Secure>{});
    }
 
    void
    operator()(void const* data, std::size_t size) noexcept
    {
        h_(data, size);
    }
 
    explicit
    operator result_type() noexcept
    {
        auto const digest = sha512_hasher::result_type(h_);
        return result_type::fromVoid(digest.data());
    }
 
private:
    inline void
    erase(std::false_type)
    {
    }
 
    inline void
    erase(std::true_type)
    {
        secure_erase(&h_, sizeof(h_));
    }
};
 
}  // namespace detail
 
using sha512_half_hasher = detail::basic_sha512_half_hasher<false>;
 
// secure version
using sha512_half_hasher_s = detail::basic_sha512_half_hasher<true>;
 
//------------------------------------------------------------------------------
 
template <class... Args>
sha512_half_hasher::result_type
sha512Half(Args const&... args)
{
    sha512_half_hasher h;
    using beast::hash_append;
    hash_append(h, args...);
    return static_cast<typename sha512_half_hasher::result_type>(h);
}
 
template <class... Args>
sha512_half_hasher_s::result_type
sha512Half_s(Args const&... args)
{
    sha512_half_hasher_s h;
    using beast::hash_append;
    hash_append(h, args...);
    return static_cast<typename sha512_half_hasher_s::result_type>(h);
}
 
}  // namespace ripple
 
#endif