HMAC は関数一発で計算できたんかい。

hmac.h

#pragma once

#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif

#pragma comment (lib, "bcrypt")

#include <Windows.h>
#include <bcrypt.h>

#include <array>
#include <system_error>


class ntstatus_error_category : public std::error_category
{
public:
	const char * name() const noexcept override
	{
		return "ntstatus";
	}

	std::string message(int ev) const override
	{
		std::string msg;

		if (HMODULE src = ::LoadLibrary(TEXT("NTDLL.DLL")))
		{
			void * buf{};

			constexpr DWORD flags = FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_FROM_HMODULE;

			if (::FormatMessageA(flags, src, ev, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), (LPSTR) &buf, 0, nullptr))
			{
				msg = (const char *) buf;
			}

			::LocalFree(buf);

			::FreeLibrary(src);
		}

		return msg;
	}
};


inline void hmac_md5(unsigned char * data, size_t data_len, unsigned char * key, size_t key_len, std::array<unsigned char, 16> & digest)
{
	if (auto status = ::BCryptHash(BCRYPT_HMAC_MD5_ALG_HANDLE, key, key_len, data, data_len, digest.data(), digest.size()))
	{
		throw std::system_error(status, ntstatus_error_category(), __FUNCTION__);
	}
}


inline void hmac_sha1(unsigned char * data, size_t data_len, unsigned char * key, size_t key_len, std::array<unsigned char, 20> & digest)
{
	if (auto status = ::BCryptHash(BCRYPT_HMAC_SHA1_ALG_HANDLE, key, key_len, data, data_len, digest.data(), digest.size()))
	{
		throw std::system_error(status, ntstatus_error_category(), __FUNCTION__);
	}
}

test.cpp

#include "gtest/gtest.h"
#include "hmac.h"
#include <numeric>

TEST(RFC2202, MD5_test_case_1)
{
	std::array<unsigned char, 16> key;
	key.fill(0x0b);

	unsigned char data[] = "Hi There";

	std::array<unsigned char, 16> expected{ 0x92, 0x94, 0x72, 0x7a, 0x36, 0x38, 0xbb, 0x1c, 0x13, 0xf4, 0x8e, 0xf8, 0x15, 0x8b, 0xfc, 0x9d };
	std::array<unsigned char, 16> actual;

	hmac_md5(data, sizeof(data) - 1, key.data(), key.size(), actual);

	EXPECT_EQ(actual, expected);
}

TEST(RFC2202, MD5_test_case_2)
{
	unsigned char key[] = "Jefe";
	unsigned char data[] = "what do ya want for nothing?";

	std::array<unsigned char, 16> expected{ 0x75, 0x0c, 0x78, 0x3e, 0x6a, 0xb0, 0xb5, 0x03, 0xea, 0xa8, 0x6e, 0x31, 0x0a, 0x5d, 0xb7, 0x38 };
	std::array<unsigned char, 16> actual;

	hmac_md5(data, sizeof(data) - 1, key, sizeof(key) - 1, actual);

	EXPECT_EQ(actual, expected);
}

TEST(RFC2202, MD5_test_case_3)
{
	std::array<unsigned char, 16> key;
	key.fill(0xAA);

	std::array<unsigned char, 50> data;
	data.fill(0xDD);

	std::array<unsigned char, 16> expected{ 0x56, 0xbe, 0x34, 0x52, 0x1d, 0x14, 0x4c, 0x88, 0xdb, 0xb8, 0xc7, 0x33, 0xf0, 0xe8, 0xb3, 0xf6 };
	std::array<unsigned char, 16> actual;

	hmac_md5(data.data(), data.size(), key.data(), key.size(), actual);

	EXPECT_EQ(actual, expected);
}

TEST(RFC2202, MD5_test_case_4)
{
	std::array<unsigned char, 25> key;
	std::iota(key.begin(), key.end(), 1);

	std::array<unsigned char, 50> data;
	data.fill(0xCD);

	std::array<unsigned char, 16> expected{ 0x69, 0x7e, 0xaf, 0x0a, 0xca, 0x3a, 0x3a, 0xea, 0x3a, 0x75, 0x16, 0x47, 0x46, 0xff, 0xaa, 0x79 };
	std::array<unsigned char, 16> actual;

	hmac_md5(data.data(), data.size(), key.data(), key.size(), actual);

	EXPECT_EQ(actual, expected);
}

TEST(RFC2202, MD5_test_case_5)
{
	std::array<unsigned char, 16> key;
	key.fill(0x0C);

	unsigned char data[] = "Test With Truncation";

	std::array<unsigned char, 16> expected{ 0x56, 0x46, 0x1e, 0xf2, 0x34, 0x2e, 0xdc, 0x00, 0xf9, 0xba, 0xb9, 0x95, 0x69, 0x0e, 0xfd, 0x4c };
	std::array<unsigned char, 16> actual;

	hmac_md5(data, sizeof(data) - 1, key.data(), key.size(), actual);

	EXPECT_EQ(actual, expected);
}

TEST(RFC2202, MD5_test_case_6)
{
	std::array<unsigned char, 80> key;
	key.fill(0xAA);

	unsigned char data[] = "Test Using Larger Than Block-Size Key - Hash Key First";

	std::array<unsigned char, 16> expected{ 0x6b, 0x1a, 0xb7, 0xfe, 0x4b, 0xd7, 0xbf, 0x8f, 0x0b, 0x62, 0xe6, 0xce, 0x61, 0xb9, 0xd0, 0xcd };
	std::array<unsigned char, 16> actual;

	hmac_md5(data, sizeof(data) - 1, key.data(), key.size(), actual);

	EXPECT_EQ(actual, expected);
}

TEST(RFC2202, MD5_test_case_7)
{
	std::array<unsigned char, 80> key;
	key.fill(0xAA);

	unsigned char data[] = "Test Using Larger Than Block-Size Key and Larger Than One Block-Size Data";

	std::array<unsigned char, 16> expected{ 0x6f, 0x63, 0x0f, 0xad, 0x67, 0xcd, 0xa0, 0xee, 0x1f, 0xb1, 0xf5, 0x62, 0xdb, 0x3a, 0xa5, 0x3e };
	std::array<unsigned char, 16> actual;

	hmac_md5(data, sizeof(data) - 1, key.data(), key.size(), actual);

	EXPECT_EQ(actual, expected);
}

TEST(RFC2202, SHA1_test_case_1)
{
	std::array<unsigned char, 20> key;
	key.fill(0x0B);

	unsigned char data[] = "Hi There";

	std::array<unsigned char, 20> expected{ 0xb6, 0x17, 0x31, 0x86, 0x55, 0x05, 0x72, 0x64, 0xe2, 0x8b, 0xc0, 0xb6, 0xfb, 0x37, 0x8c, 0x8e, 0xf1, 0x46, 0xbe, 0x00 };
	std::array<unsigned char, 20> actual;

	hmac_sha1(data, sizeof(data) - 1, key.data(), key.size(), actual);

	EXPECT_EQ(actual, expected);
}

TEST(RFC2202, SHA1_test_case_2)
{
	unsigned char key[] = "Jefe";
	unsigned char data[] = "what do ya want for nothing?";

	std::array<unsigned char, 20> expected{ 0xef, 0xfc, 0xdf, 0x6a, 0xe5, 0xeb, 0x2f, 0xa2, 0xd2, 0x74, 0x16, 0xd5, 0xf1, 0x84, 0xdf, 0x9c, 0x25, 0x9a, 0x7c, 0x79 };
	std::array<unsigned char, 20> actual;

	hmac_sha1(data, sizeof(data) - 1, key, sizeof(key) - 1, actual);

	EXPECT_EQ(actual, expected);
}

TEST(RFC2202, SHA1_test_case_3)
{
	std::array<unsigned char, 20> key;
	key.fill(0xAA);

	std::array<unsigned char, 50> data;
	data.fill(0xDD);

	std::array<unsigned char, 20> expected{ 0x12, 0x5d, 0x73, 0x42, 0xb9, 0xac, 0x11, 0xcd, 0x91, 0xa3, 0x9a, 0xf4, 0x8a, 0xa1, 0x7b, 0x4f, 0x63, 0xf1, 0x75, 0xd3 };
	std::array<unsigned char, 20> actual;

	hmac_sha1(data.data(), data.size(), key.data(), key.size(), actual);

	EXPECT_EQ(actual, expected);
}

TEST(RFC2202, SHA1_test_case_4)
{
	std::array<unsigned char, 25> key;
	std::iota(key.begin(), key.end(), 1);

	std::array<unsigned char, 50> data;
	data.fill(0xCD);

	std::array<unsigned char, 20> expected{ 0x4c, 0x90, 0x07, 0xf4, 0x02, 0x62, 0x50, 0xc6, 0xbc, 0x84, 0x14, 0xf9, 0xbf, 0x50, 0xc8, 0x6c, 0x2d, 0x72, 0x35, 0xda };
	std::array<unsigned char, 20> actual;

	hmac_sha1(data.data(), data.size(), key.data(), key.size(), actual);

	EXPECT_EQ(actual, expected);
}

TEST(RFC2202, SHA1_test_case_5)
{
	std::array<unsigned char, 20> key;
	key.fill(0x0C);

	unsigned char data[] = "Test With Truncation";

	std::array<unsigned char, 20> expected{ 0x4c, 0x1a, 0x03, 0x42, 0x4b, 0x55, 0xe0, 0x7f, 0xe7, 0xf2, 0x7b, 0xe1, 0xd5, 0x8b, 0xb9, 0x32, 0x4a, 0x9a, 0x5a, 0x04 };
	std::array<unsigned char, 20> actual;

	hmac_sha1(data, sizeof(data) - 1, key.data(), key.size(), actual);

	EXPECT_EQ(actual, expected);
}

TEST(RFC2202, SHA1_test_case_6)
{
	std::array<unsigned char, 80> key;
	key.fill(0xAA);

	unsigned char data[] = "Test Using Larger Than Block-Size Key - Hash Key First";

	std::array<unsigned char, 20> expected{ 0xaa, 0x4a, 0xe5, 0xe1, 0x52, 0x72, 0xd0, 0x0e, 0x95, 0x70, 0x56, 0x37, 0xce, 0x8a, 0x3b, 0x55, 0xed, 0x40, 0x21, 0x12 };
	std::array<unsigned char, 20> actual;

	hmac_sha1(data, sizeof(data) - 1, key.data(), key.size(), actual);

	EXPECT_EQ(actual, expected);
}

TEST(RFC2202, SHA1_test_case_7)
{
	std::array<unsigned char, 80> key;
	key.fill(0xAA);

	unsigned char data[] = "Test Using Larger Than Block-Size Key and Larger Than One Block-Size Data";

	std::array<unsigned char, 20> expected{ 0xe8, 0xe9, 0x9d, 0x0f, 0x45, 0x23, 0x7d, 0x78, 0x6d, 0x6b, 0xba, 0xa7, 0x96, 0x5c, 0x78, 0x08, 0xbb, 0xff, 0x1a, 0x91 };
	std::array<unsigned char, 20> actual;

	hmac_sha1(data, sizeof(data) - 1, key.data(), key.size(), actual);

	EXPECT_EQ(actual, expected);
}

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