StdCrypt:

- stronger randomizer;
- ability to validate passwords;
- anti-brutforce key encryption

git-svn-id: http://svn.miranda-ng.org/main/trunk@6919 1316c22d-e87f-b044-9b9b-93d7a3e3ba9c

12 files changed, 459 insertions, 47 deletions

diff --git a/src/core/stdcrypt/Rijndael.cpp b/src/core/stdcrypt/Rijndael.cpp
index 150589f83b..fd9cf84d83 100644
--- a/src/core/stdcrypt/Rijndael.cpp
+++ b/src/core/stdcrypt/Rijndael.cpp
@@ -951,7 +951,7 @@ CRijndael::~CRijndael()
 // chain      - initial chain block

 // keylength  - 16, 24 or 32 bytes

 // blockSize  - The block size in bytes of this Rijndael (16, 24 or 32 bytes).

-int CRijndael::MakeKey(char const* key, char const* chain, int keylength, int blockSize)

+int CRijndael::MakeKey(BYTE const* key, char const* chain, int keylength, int blockSize)

 {

 	if (NULL == key)

 		return 1;

@@ -992,12 +992,12 @@ int CRijndael::MakeKey(char const* key, char const* chain, int keylength, int bl
 	int KC = m_keylength / 4;

 	//Copy user material bytes into temporary ints

 	int* pi = tk;

-	char const* pc = key;

+	BYTE const* pc = key;

 	for (i = 0; i < KC; i++) {

-		*pi = (unsigned char)*(pc++) << 24;

-		*pi |= (unsigned char)*(pc++) << 16;

-		*pi |= (unsigned char)*(pc++) << 8;

-		*(pi++) |= (unsigned char)*(pc++);

+		*pi = *(pc++) << 24;

+		*pi |= *(pc++) << 16;

+		*pi |= *(pc++) << 8;

+		*(pi++) |= *(pc++);

 	}

 	//Copy values into round key arrays

 	int t = 0;

@@ -1296,7 +1296,7 @@ void CRijndael::DecryptBlock(char const* in, char* result)
 	}

 }

 

-int CRijndael::Encrypt(char const* in, char* result, size_t n)

+int CRijndael::Encrypt(void const* in, void* result, size_t n)

 {

 	if (!m_bKeyInit)

 		return 1;

@@ -1305,11 +1305,10 @@ int CRijndael::Encrypt(char const* in, char* result, size_t n)
 	if (0 == n || n%m_blockSize != 0)

 		return 2;

 

-	int i;

-	char const* pin;

-	char* presult;

+	char const* pin = (char const*)in;

+	char* presult = (char*)result;

 

-	for (i = 0, pin = in, presult = result; i < n / m_blockSize; i++) {

+	for (int i = 0; i < n / m_blockSize; i++) {

 		Xor(m_chain, pin);

 		EncryptBlock(m_chain, presult);

 		memcpy(m_chain, presult, m_blockSize);

@@ -1319,7 +1318,7 @@ int CRijndael::Encrypt(char const* in, char* result, size_t n)
 	return 0;

 }

 

-int CRijndael::Decrypt(char const* in, char* result, size_t n)

+int CRijndael::Decrypt(void const* in, void* result, size_t n)

 {

 	if (!m_bKeyInit)

 		return 1;

@@ -1327,11 +1326,10 @@ int CRijndael::Decrypt(char const* in, char* result, size_t n)
 	if (0 == n || n%m_blockSize != 0)

 		return 2;

 

-	int i;

-	char const* pin;

-	char* presult;

+	char const* pin = (char const*)in;

+	char* presult = (char*)result;

 

-	for (i = 0, pin = in, presult = result; i < n / m_blockSize; i++) {

+	for (int i = 0; i < n / m_blockSize; i++) {

 		DecryptBlock(pin, presult);

 		Xor(presult, m_chain);

 		memcpy(m_chain, pin, m_blockSize);

diff --git a/src/core/stdcrypt/Rijndael.h b/src/core/stdcrypt/Rijndael.h
index a904259eb5..a69409b929 100644
--- a/src/core/stdcrypt/Rijndael.h
+++ b/src/core/stdcrypt/Rijndael.h
@@ -33,7 +33,7 @@ public:
 	// chain      - initial chain block

 	// keylength  - 16, 24 or 32 bytes

 	// blockSize  - The block size in bytes of this Rijndael (16, 24 or 32 bytes).

-	int MakeKey(char const* key, char const* chain, int keylength, int blockSize);

+	int MakeKey(BYTE const* key, char const* chain, int keylength, int blockSize);

 

 private:

 	//Auxiliary Function

@@ -66,9 +66,9 @@ public:
 	// result     - The plaintext generated from a ciphertext using the session key.

 	void DecryptBlock(char const* in, char* result);

 

-	int Encrypt(char const* in, char* result, size_t n);

+	int Encrypt(void const* in, void* result, size_t n);

 	

-	int Decrypt(char const* in, char* result, size_t n);

+	int Decrypt(void const* in, void* result, size_t n);

 

 	//Get Key Length

 	int GetKeyLength()

diff --git a/src/core/stdcrypt/commonheaders.h b/src/core/stdcrypt/commonheaders.h
index f89df739dd..37168497d8 100644
--- a/src/core/stdcrypt/commonheaders.h
+++ b/src/core/stdcrypt/commonheaders.h
@@ -76,3 +76,6 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 #include "stdcrypt.h"

 

 extern HINSTANCE hInst;

+

+bool getRandomBytes(BYTE *buf, size_t bufLen);

+void slow_hash(const void *buf, size_t bufLen, BYTE tmpHash[32]);

diff --git a/src/core/stdcrypt/encrypt.cpp b/src/core/stdcrypt/encrypt.cpp
index 7414d999f3..00e52935d8 100644
--- a/src/core/stdcrypt/encrypt.cpp
+++ b/src/core/stdcrypt/encrypt.cpp
@@ -23,6 +23,15 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 

 #include "commonheaders.h"

 

+#include "..\..\..\plugins\zlib\src\zlib.h"

+

+struct ExternalKey

+{

+	BYTE  m_key[KEY_LENGTH];

+	DWORD m_crc32;

+	BYTE  slack[BLOCK_SIZE - sizeof(DWORD)];

+};

+

 CStdCrypt::CStdCrypt() :

 	m_password("Miranda")

 {}

@@ -34,47 +43,61 @@ void CStdCrypt::destroy()
 

 size_t CStdCrypt::getKeyLength()

 {

-	return KEY_LENGTH;

+	return sizeof(ExternalKey);

 }

 

 bool CStdCrypt::getKey(BYTE *pKey, size_t cbKeyLen)

 {

-	if (!m_valid || cbKeyLen < KEY_LENGTH)

+	if (!m_valid || cbKeyLen < sizeof(ExternalKey))

 		return false;

 

-	memcpy(pKey, m_key, sizeof(m_key));

-	if (cbKeyLen > KEY_LENGTH)

-		memset(pKey + KEY_LENGTH, 0, cbKeyLen - KEY_LENGTH);

+	ExternalKey tmp = { 0 };

+	memcpy(&tmp.m_key, m_key, KEY_LENGTH);

+	tmp.m_crc32 = crc32(0xAbbaDead, (LPCBYTE)m_password.GetString(), m_password.GetLength());

+	getRandomBytes(tmp.slack, sizeof(tmp.slack));

+

+	BYTE tmpHash[32];

+	slow_hash(m_password, m_password.GetLength(), tmpHash);

+

+	CRijndael tmpAes;

+	tmpAes.MakeKey(tmpHash, tmpAes.sm_chain0, KEY_LENGTH, BLOCK_SIZE);

+	tmpAes.Encrypt(&tmp, pKey, sizeof(tmp));

 	return true;

 }

 

-int CStdCrypt::setKey(const BYTE *pKey, size_t cbKeyLen)

+bool CStdCrypt::setKey(const BYTE *pKey, size_t cbKeyLen)

 {

-	if (cbKeyLen > KEY_LENGTH)

-		return false;

-

-	memcpy(m_key, pKey, cbKeyLen);

-	if (cbKeyLen < KEY_LENGTH)

-		memset(m_key + cbKeyLen, 0, KEY_LENGTH - cbKeyLen);

+	ExternalKey tmp = { 0 };

+

+	// full external key. decode & check password

+	if (cbKeyLen == sizeof(tmp)) { 

+		BYTE tmpHash[32];

+		slow_hash(m_password, m_password.GetLength(), tmpHash);

+

+		CRijndael tmpAes;

+		tmpAes.MakeKey(tmpHash, tmpAes.sm_chain0, KEY_LENGTH, BLOCK_SIZE);

+		tmpAes.Decrypt(pKey, &tmp, sizeof(tmp));

+		if (tmp.m_crc32 != crc32(0xAbbaDead, (LPCBYTE)m_password.GetString(), m_password.GetLength()))

+			return false;

+	}

+	// new key. simply copy it

+	else if (cbKeyLen == KEY_LENGTH) {

+		memcpy(&tmp.m_key, pKey, KEY_LENGTH);

+	}

+	else return false;

 

+	memcpy(m_key, &tmp.m_key, KEY_LENGTH);

 	m_aes.MakeKey(m_key, m_password, KEY_LENGTH, BLOCK_SIZE);

-	m_valid = true;

-	return 0;

+	return m_valid = true;

 }

 

-void CStdCrypt::generateKey(void)

+bool CStdCrypt::generateKey(void)

 {

-	LARGE_INTEGER counter;

-	QueryPerformanceCounter(&counter);

-	srand(counter.LowPart);

-

-	for (int i = 0; i < sizeof(m_key); i++) {

-		m_key[i] = (BYTE)rand();

-		Sleep(0);

-	}

+	BYTE tmp[KEY_LENGTH];

+	if (!getRandomBytes(tmp, sizeof(tmp)))

+		return false;

 

-	m_aes.MakeKey(m_key, m_password, KEY_LENGTH, BLOCK_SIZE);

-	m_valid = true;

+	return setKey(tmp, sizeof(tmp));

 }

 

 void CStdCrypt::purgeKey(void)

diff --git a/src/core/stdcrypt/stdcrypt.h b/src/core/stdcrypt/stdcrypt.h
index f685152461..c9a3a72315 100644
--- a/src/core/stdcrypt/stdcrypt.h
+++ b/src/core/stdcrypt/stdcrypt.h
@@ -31,7 +31,7 @@ struct CStdCrypt : public MICryptoEngine, public MZeroedObject
 	BOOL      m_valid;

 	CMStringA m_password;

 

-	char      m_key[KEY_LENGTH];

+	BYTE      m_key[KEY_LENGTH];

 	CRijndael m_aes;

 

 	STDMETHODIMP_(void) destroy();

@@ -39,9 +39,9 @@ struct CStdCrypt : public MICryptoEngine, public MZeroedObject
 	// get/set the instance key

 	STDMETHODIMP_(size_t) getKeyLength(void);

 	STDMETHODIMP_(bool) getKey(BYTE *pKey, size_t cbKeyLen);

-	STDMETHODIMP_(int) setKey(const BYTE *pKey, size_t cbKeyLen);

+	STDMETHODIMP_(bool) setKey(const BYTE *pKey, size_t cbKeyLen);

 

-	STDMETHODIMP_(void) generateKey(void); // creates a new key inside

+	STDMETHODIMP_(bool) generateKey(void); // creates a new key inside

 	STDMETHODIMP_(void) purgeKey(void);    // purges a key from memory

 

 	// sets the master password (in utf-8)

diff --git a/src/core/stdcrypt/stdcrypt_10.vcxproj b/src/core/stdcrypt/stdcrypt_10.vcxproj
index 8f190d3c66..4d5c61ade3 100644
--- a/src/core/stdcrypt/stdcrypt_10.vcxproj
+++ b/src/core/stdcrypt/stdcrypt_10.vcxproj
@@ -208,6 +208,7 @@
     <ClCompile Include="encrypt.cpp" />

     <ClCompile Include="main.cpp" />

     <ClCompile Include="Rijndael.cpp" />

+    <ClCompile Include="utils.cpp" />

   </ItemGroup>

   <ItemGroup>

     <ClInclude Include="..\..\..\include\m_crypto.h" />

@@ -220,6 +221,11 @@
     <ResourceCompile Include="resource.rc" />

     <ResourceCompile Include="version.rc" />

   </ItemGroup>

+  <ItemGroup>

+    <ProjectReference Include="..\..\..\plugins\Zlib\zlib_10.vcxproj">

+      <Project>{e2a369cd-eda3-414f-8ad0-e732cd7ee68c}</Project>

+    </ProjectReference>

+  </ItemGroup>

   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />

   <ImportGroup Label="ExtensionTargets">

   </ImportGroup>

diff --git a/src/core/stdcrypt/stdcrypt_10.vcxproj.filters b/src/core/stdcrypt/stdcrypt_10.vcxproj.filters
index 3976d8f7be..970fd73212 100644
--- a/src/core/stdcrypt/stdcrypt_10.vcxproj.filters
+++ b/src/core/stdcrypt/stdcrypt_10.vcxproj.filters
@@ -27,6 +27,9 @@
     <ClCompile Include="Rijndael.cpp">

       <Filter>Source Files</Filter>

     </ClCompile>

+    <ClCompile Include="utils.cpp">

+      <Filter>Source Files</Filter>

+    </ClCompile>

   </ItemGroup>

   <ItemGroup>

     <ClInclude Include="..\stdplug.h">

diff --git a/src/core/stdcrypt/stdcrypt_11.vcxproj b/src/core/stdcrypt/stdcrypt_11.vcxproj
index 387bea51e3..84aa88e8f7 100644
--- a/src/core/stdcrypt/stdcrypt_11.vcxproj
+++ b/src/core/stdcrypt/stdcrypt_11.vcxproj
@@ -211,6 +211,7 @@
     <ClCompile Include="encrypt.cpp" />

     <ClCompile Include="main.cpp" />

     <ClCompile Include="Rijndael.cpp" />

+    <ClCompile Include="utils.cpp" />

   </ItemGroup>

   <ItemGroup>

     <ClInclude Include="..\..\..\include\m_crypto.h" />

@@ -223,6 +224,11 @@
     <ResourceCompile Include="resource.rc" />

     <ResourceCompile Include="version.rc" />

   </ItemGroup>

+  <ItemGroup>

+    <ProjectReference Include="..\..\..\plugins\Zlib\zlib_11.vcxproj">

+      <Project>{e2a369cd-eda3-414f-8ad0-e732cd7ee68c}</Project>

+    </ProjectReference>

+  </ItemGroup>

   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />

   <ImportGroup Label="ExtensionTargets">

   </ImportGroup>

diff --git a/src/core/stdcrypt/stdcrypt_11.vcxproj.filters b/src/core/stdcrypt/stdcrypt_11.vcxproj.filters
index 3976d8f7be..970fd73212 100644
--- a/src/core/stdcrypt/stdcrypt_11.vcxproj.filters
+++ b/src/core/stdcrypt/stdcrypt_11.vcxproj.filters
@@ -27,6 +27,9 @@
     <ClCompile Include="Rijndael.cpp">

       <Filter>Source Files</Filter>

     </ClCompile>

+    <ClCompile Include="utils.cpp">

+      <Filter>Source Files</Filter>

+    </ClCompile>

   </ItemGroup>

   <ItemGroup>

     <ClInclude Include="..\stdplug.h">

diff --git a/src/core/stdcrypt/stdcrypt_12.vcxproj b/src/core/stdcrypt/stdcrypt_12.vcxproj
index 1ba2bf66ef..a80aca86c6 100644
--- a/src/core/stdcrypt/stdcrypt_12.vcxproj
+++ b/src/core/stdcrypt/stdcrypt_12.vcxproj
@@ -211,6 +211,7 @@
     <ClCompile Include="encrypt.cpp" />

     <ClCompile Include="main.cpp" />

     <ClCompile Include="Rijndael.cpp" />

+    <ClCompile Include="utils.cpp" />

   </ItemGroup>

   <ItemGroup>

     <ClInclude Include="..\..\..\include\m_crypto.h" />

@@ -223,6 +224,11 @@
     <ResourceCompile Include="resource.rc" />

     <ResourceCompile Include="version.rc" />

   </ItemGroup>

+  <ItemGroup>

+    <ProjectReference Include="..\..\..\plugins\Zlib\zlib_12.vcxproj">

+      <Project>{e2a369cd-eda3-414f-8ad0-e732cd7ee68c}</Project>

+    </ProjectReference>

+  </ItemGroup>

   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />

   <ImportGroup Label="ExtensionTargets">

   </ImportGroup>

diff --git a/src/core/stdcrypt/stdcrypt_12.vcxproj.filters b/src/core/stdcrypt/stdcrypt_12.vcxproj.filters
index 3976d8f7be..970fd73212 100644
--- a/src/core/stdcrypt/stdcrypt_12.vcxproj.filters
+++ b/src/core/stdcrypt/stdcrypt_12.vcxproj.filters
@@ -27,6 +27,9 @@
     <ClCompile Include="Rijndael.cpp">

       <Filter>Source Files</Filter>

     </ClCompile>

+    <ClCompile Include="utils.cpp">

+      <Filter>Source Files</Filter>

+    </ClCompile>

   </ItemGroup>

   <ItemGroup>

     <ClInclude Include="..\stdplug.h">

diff --git a/src/core/stdcrypt/utils.cpp b/src/core/stdcrypt/utils.cpp
new file mode 100644
index 0000000000..c9bdb70c43
--- /dev/null
+++ b/src/core/stdcrypt/utils.cpp
@@ -0,0 +1,361 @@
+/*

+

+Miranda NG: the free IM client for Microsoft* Windows*

+

+Copyright (C) 2012-13 Miranda NG project,

+all portions of this codebase are copyrighted to the people

+listed in contributors.txt.

+

+This program is free software; you can redistribute it and/or

+modify it under the terms of the GNU General Public License

+as published by the Free Software Foundation; either version 2

+of the License, or (at your option) any later version.

+

+This program is distributed in the hope that it will be useful,

+but WITHOUT ANY WARRANTY; without even the implied warranty of

+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

+GNU General Public License for more details.

+

+You should have received a copy of the GNU General Public License

+along with this program; if not, write to the Free Software

+Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

+*/

+

+#include "commonheaders.h"

+

+bool getRandomBytes(BYTE *buf, size_t bufLen)

+{

+	// try to use Intel hardware randomizer first

+	HCRYPTPROV hProvider = NULL;

+	if (::CryptAcquireContext(&hProvider, NULL, _T("Intel Hardware Cryptographic Service Provider"), PROV_INTEL_SEC, 0)) {

+		::CryptGenRandom(hProvider, DWORD(bufLen), buf);

+		::CryptReleaseContext(hProvider, 0);

+	}

+	// no luck? try to use RSA

+	else if (::CryptAcquireContext(&hProvider, NULL, NULL, PROV_RSA_FULL, CRYPT_VERIFYCONTEXT)) {

+		::CryptGenRandom(hProvider, DWORD(bufLen), buf);

+		::CryptReleaseContext(hProvider, 0);

+	}

+	// no luck? try to use Windows NT RTL

+	else {

+		typedef BOOL(WINAPI *pfnGetRandom)(PVOID RandomBuffer, ULONG RandomBufferLength);

+		pfnGetRandom fnGetRandom = (pfnGetRandom)GetProcAddress(GetModuleHandleA("advapi32.dll"), "SystemFunction036");

+		if (fnGetRandom == NULL)

+			return false;

+

+		fnGetRandom(buf, DWORD(bufLen));

+	}

+	return true;

+}

+

+/////////////////////////////////////////////////////////////////////////////////////////

+

+struct SHA256_CONTEXT
+{
+	UINT32  h0, h1, h2, h3, h4, h5, h6, h7;
+	UINT32  nblocks;
+	BYTE buf[64];
+	int  count;
+};
+
+static void sha256_init(SHA256_CONTEXT *hd)
+{
+	hd->h0 = 0x6a09e667;
+	hd->h1 = 0xbb67ae85;
+	hd->h2 = 0x3c6ef372;
+	hd->h3 = 0xa54ff53a;
+	hd->h4 = 0x510e527f;
+	hd->h5 = 0x9b05688c;
+	hd->h6 = 0x1f83d9ab;
+	hd->h7 = 0x5be0cd19;
+
+	hd->nblocks = 0;
+	hd->count = 0;
+}
+
+/*
+Transform the message X which consists of 16 32-bit-words. See FIPS
+180-2 for details.  */
+#define ror(x,n) ( ((x) >> (n)) | ((x) << (32-(n))) )
+#define S0(x) (ror ((x), 7) ^ ror ((x), 18) ^ ((x) >> 3))       /* (4.6) */
+#define S1(x) (ror ((x), 17) ^ ror ((x), 19) ^ ((x) >> 10))     /* (4.7) */
+#define R(a,b,c,d,e,f,g,h,k,w) do                                 \
+{                                                       \
+	t1 = (h)+Sum1((e)) + Cho((e), (f), (g)) + (k)+(w);  \
+	t2 = Sum0((a)) + Maj((a), (b), (c));                    \
+	h = g;                                                \
+	g = f;                                                \
+	f = e;                                                \
+	e = d + t1;                                           \
+	d = c;                                                \
+	c = b;                                                \
+	b = a;                                                \
+	a = t1 + t2;                                          \
+} while (0)
+
+/* (4.2) same as SHA-1's F1.  */
+static inline UINT32
+Cho(UINT32 x, UINT32 y, UINT32 z)
+{
+	return (z ^ (x & (y ^ z)));
+}
+
+/* (4.3) same as SHA-1's F3 */
+static inline UINT32
+Maj(UINT32 x, UINT32 y, UINT32 z)
+{
+	return ((x & y) | (z & (x | y)));
+}
+
+/* (4.4) */
+static inline UINT32 Sum0(UINT32 x)
+{
+	return (ror(x, 2) ^ ror(x, 13) ^ ror(x, 22));
+}
+
+/* (4.5) */
+static inline UINT32
+Sum1(UINT32 x)
+{
+	return (ror(x, 6) ^ ror(x, 11) ^ ror(x, 25));
+}
+
+
+static void transform(SHA256_CONTEXT *hd, const unsigned char *data)
+{
+	static const UINT32 K[64] = {
+		0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5,
+		0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5,
+		0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3,
+		0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174,
+		0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc,
+		0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
+		0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7,
+		0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967,
+		0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13,
+		0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85,
+		0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3,
+		0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
+		0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5,
+		0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3,
+		0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208,
+		0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2
+	};
+
+	UINT32 a, b, c, d, e, f, g, h, t1, t2;
+	UINT32 x[16];
+	UINT32 w[64];
+	int i;
+
+	a = hd->h0;
+	b = hd->h1;
+	c = hd->h2;
+	d = hd->h3;
+	e = hd->h4;
+	f = hd->h5;
+	g = hd->h6;
+	h = hd->h7;
+
+#ifdef WORDS_BIGENDIAN
+	memcpy(x, data, 64);
+#else
+	{
+		BYTE *p2;
+
+		for (i = 0, p2 = (BYTE*)x; i < 16; i++, p2 += 4) {
+			p2[3] = *data++;
+			p2[2] = *data++;
+			p2[1] = *data++;
+			p2[0] = *data++;
+		}
+	}
+#endif
+
+	for (i = 0; i < 16; i++)
+		w[i] = x[i];
+	for (; i < 64; i++)
+		w[i] = S1(w[i - 2]) + w[i - 7] + S0(w[i - 15]) + w[i - 16];
+
+	for (i = 0; i < 64;)
+	{
+#if 0
+		R(a, b, c, d, e, f, g, h, K[i], w[i]);
+		i++;
+#else
+		t1 = h + Sum1(e) + Cho(e, f, g) + K[i] + w[i];
+		t2 = Sum0(a) + Maj(a, b, c);
+		d += t1;
+		h = t1 + t2;
+
+		t1 = g + Sum1(d) + Cho(d, e, f) + K[i + 1] + w[i + 1];
+		t2 = Sum0(h) + Maj(h, a, b);
+		c += t1;
+		g = t1 + t2;
+
+		t1 = f + Sum1(c) + Cho(c, d, e) + K[i + 2] + w[i + 2];
+		t2 = Sum0(g) + Maj(g, h, a);
+		b += t1;
+		f = t1 + t2;
+
+		t1 = e + Sum1(b) + Cho(b, c, d) + K[i + 3] + w[i + 3];
+		t2 = Sum0(f) + Maj(f, g, h);
+		a += t1;
+		e = t1 + t2;
+
+		t1 = d + Sum1(a) + Cho(a, b, c) + K[i + 4] + w[i + 4];
+		t2 = Sum0(e) + Maj(e, f, g);
+		h += t1;
+		d = t1 + t2;
+
+		t1 = c + Sum1(h) + Cho(h, a, b) + K[i + 5] + w[i + 5];
+		t2 = Sum0(d) + Maj(d, e, f);
+		g += t1;
+		c = t1 + t2;
+
+		t1 = b + Sum1(g) + Cho(g, h, a) + K[i + 6] + w[i + 6];
+		t2 = Sum0(c) + Maj(c, d, e);
+		f += t1;
+		b = t1 + t2;
+
+		t1 = a + Sum1(f) + Cho(f, g, h) + K[i + 7] + w[i + 7];
+		t2 = Sum0(b) + Maj(b, c, d);
+		e += t1;
+		a = t1 + t2;
+
+		i += 8;
+#endif
+	}
+
+	hd->h0 += a;
+	hd->h1 += b;
+	hd->h2 += c;
+	hd->h3 += d;
+	hd->h4 += e;
+	hd->h5 += f;
+	hd->h6 += g;
+	hd->h7 += h;
+}
+#undef S0
+#undef S1
+#undef R
+
+
+/* Update the message digest with the contents of INBUF with length
+INLEN.  */
+static void sha256_write(SHA256_CONTEXT *hd, const void *inbuf_arg, size_t inlen)
+{
+	const unsigned char *inbuf = (const unsigned char *)inbuf_arg;
+
+	if (hd->count == 64)
+	{ /* flush the buffer */
+		transform(hd, hd->buf);
+		hd->count = 0;
+		hd->nblocks++;
+	}
+	if (!inbuf)
+		return;
+	if (hd->count)
+	{
+		for (; inlen && hd->count < 64; inlen--)
+			hd->buf[hd->count++] = *inbuf++;
+		sha256_write(hd, NULL, 0);
+		if (!inlen)
+			return;
+	}
+
+	while (inlen >= 64)
+	{
+		transform(hd, inbuf);
+		hd->count = 0;
+		hd->nblocks++;
+		inlen -= 64;
+		inbuf += 64;
+	}
+	for (; inlen && hd->count < 64; inlen--)
+		hd->buf[hd->count++] = *inbuf++;
+}
+
+
+/*
+The routine finally terminates the computation and returns the
+digest.  The handle is prepared for a new cycle, but adding bytes
+to the handle will the destroy the returned buffer.  Returns: 32
+bytes with the message the digest.  */
+static void sha256_final(SHA256_CONTEXT *hd, BYTE tmpHash[32])
+{
+	UINT32 t, msb, lsb;
+
+	sha256_write(hd, NULL, 0); /* flush */;
+
+	t = hd->nblocks;
+	/* multiply by 64 to make a BYTE count */
+	lsb = t << 6;
+	msb = t >> 26;
+	/* add the count */
+	t = lsb;
+	if ((lsb += hd->count) < t)
+		msb++;
+	/* multiply by 8 to make a bit count */
+	t = lsb;
+	lsb <<= 3;
+	msb <<= 3;
+	msb |= t >> 29;
+
+	if (hd->count < 56)
+	{ /* enough room */
+		hd->buf[hd->count++] = 0x80; /* pad */
+		while (hd->count < 56)
+			hd->buf[hd->count++] = 0;  /* pad */
+	}
+	else
+	{ /* need one extra block */
+		hd->buf[hd->count++] = 0x80; /* pad character */
+		while (hd->count < 64)
+			hd->buf[hd->count++] = 0;
+		sha256_write(hd, NULL, 0);  /* flush */;
+		memset(hd->buf, 0, 56); /* fill next block with zeroes */
+	}
+	/* append the 64 bit count */
+	hd->buf[56] = msb >> 24;
+	hd->buf[57] = msb >> 16;
+	hd->buf[58] = msb >> 8;
+	hd->buf[59] = msb;
+	hd->buf[60] = lsb >> 24;
+	hd->buf[61] = lsb >> 16;
+	hd->buf[62] = lsb >> 8;
+	hd->buf[63] = lsb;
+	transform(hd, hd->buf);
+
+	BYTE *p = tmpHash;
+#ifdef WORDS_BIGENDIAN
+#define X(a) do { *(UINT32*)p = hd->h##a ; p += 4; } while(0)
+#else /* little endian */
+#define X(a) do { *p++ = hd->h##a >> 24; *p++ = hd->h##a >> 16;	 \
+	*p++ = hd->h##a >> 8; *p++ = hd->h##a; } while (0)
+#endif
+	X(0);
+	X(1);
+	X(2);
+	X(3);
+	X(4);
+	X(5);
+	X(6);
+	X(7);
+#undef X
+}
+

+static void make_sha256(const void *buf, size_t bufLen, BYTE tmpHash[32])

+{

+	SHA256_CONTEXT tmp;

+	sha256_init(&tmp);

+	sha256_write(&tmp, buf, bufLen);

+	sha256_final(&tmp, tmpHash);

+}

+

+void slow_hash(const void *buf, size_t bufLen, BYTE tmpHash[32])

+{

+	make_sha256(buf, bufLen, tmpHash);

+

+	for (int i = 0; i < 50000; i++)

+		make_sha256(tmpHash, sizeof(tmpHash), tmpHash);

+}