rlm@1: // 7zAes.cpp
rlm@1: 
rlm@1: #include "StdAfx.h"
rlm@1: 
rlm@1: extern "C"
rlm@1: {
rlm@1: #include "../../../C/Sha256.h"
rlm@1: }
rlm@1: 
rlm@1: #include "Windows/Synchronization.h"
rlm@1: #include "../Common/StreamObjects.h"
rlm@1: #include "../Common/StreamUtils.h"
rlm@1: #include "7zAes.h"
rlm@1: #include "MyAes.h"
rlm@1: 
rlm@1: #ifndef EXTRACT_ONLY
rlm@1: #include "RandGen.h"
rlm@1: #endif
rlm@1: 
rlm@1: using namespace NWindows;
rlm@1: 
rlm@1: namespace NCrypto {
rlm@1: namespace NSevenZ {
rlm@1: 
rlm@1: bool CKeyInfo::IsEqualTo(const CKeyInfo &a) const
rlm@1: {
rlm@1:   if (SaltSize != a.SaltSize || NumCyclesPower != a.NumCyclesPower)
rlm@1:     return false;
rlm@1:   for (UInt32 i = 0; i < SaltSize; i++)
rlm@1:     if (Salt[i] != a.Salt[i])
rlm@1:       return false;
rlm@1:   return (Password == a.Password);
rlm@1: }
rlm@1: 
rlm@1: void CKeyInfo::CalculateDigest()
rlm@1: {
rlm@1:   if (NumCyclesPower == 0x3F)
rlm@1:   {
rlm@1:     UInt32 pos;
rlm@1:     for (pos = 0; pos < SaltSize; pos++)
rlm@1:       Key[pos] = Salt[pos];
rlm@1:     for (UInt32 i = 0; i < Password.GetCapacity() && pos < kKeySize; i++)
rlm@1:       Key[pos++] = Password[i];
rlm@1:     for (; pos < kKeySize; pos++)
rlm@1:       Key[pos] = 0;
rlm@1:   }
rlm@1:   else
rlm@1:   {
rlm@1:     CSha256 sha;
rlm@1:     Sha256_Init(&sha);
rlm@1:     const UInt64 numRounds = UInt64(1) << (NumCyclesPower);
rlm@1:     Byte temp[8] = { 0,0,0,0,0,0,0,0 };
rlm@1:     for (UInt64 round = 0; round < numRounds; round++)
rlm@1:     {
rlm@1:       Sha256_Update(&sha, Salt, (size_t)SaltSize);
rlm@1:       Sha256_Update(&sha, Password, Password.GetCapacity());
rlm@1:       Sha256_Update(&sha, temp, 8);
rlm@1:       for (int i = 0; i < 8; i++)
rlm@1:         if (++(temp[i]) != 0)
rlm@1:           break;
rlm@1:     }
rlm@1:     Sha256_Final(&sha, Key);
rlm@1:   }
rlm@1: }
rlm@1: 
rlm@1: bool CKeyInfoCache::Find(CKeyInfo &key)
rlm@1: {
rlm@1:   for (int i = 0; i < Keys.Size(); i++)
rlm@1:   {
rlm@1:     const CKeyInfo &cached = Keys[i];
rlm@1:     if (key.IsEqualTo(cached))
rlm@1:     {
rlm@1:       for (int j = 0; j < kKeySize; j++)
rlm@1:         key.Key[j] = cached.Key[j];
rlm@1:       if (i != 0)
rlm@1:       {
rlm@1:         Keys.Insert(0, cached);
rlm@1:         Keys.Delete(i+1);
rlm@1:       }
rlm@1:       return true;
rlm@1:     }
rlm@1:   }
rlm@1:   return false;
rlm@1: }
rlm@1: 
rlm@1: void CKeyInfoCache::Add(CKeyInfo &key)
rlm@1: {
rlm@1:   if (Find(key))
rlm@1:     return;
rlm@1:   if (Keys.Size() >= Size)
rlm@1:     Keys.DeleteBack();
rlm@1:   Keys.Insert(0, key);
rlm@1: }
rlm@1: 
rlm@1: static CKeyInfoCache g_GlobalKeyCache(32);
rlm@1: static NSynchronization::CCriticalSection g_GlobalKeyCacheCriticalSection;
rlm@1: 
rlm@1: CBase::CBase():
rlm@1:   _cachedKeys(16),
rlm@1:   _ivSize(0)
rlm@1: {
rlm@1:   for (int i = 0; i < sizeof(_iv); i++)
rlm@1:     _iv[i] = 0;
rlm@1: }
rlm@1: 
rlm@1: void CBase::CalculateDigest()
rlm@1: {
rlm@1:   NSynchronization::CCriticalSectionLock lock(g_GlobalKeyCacheCriticalSection);
rlm@1:   if (_cachedKeys.Find(_key))
rlm@1:     g_GlobalKeyCache.Add(_key);
rlm@1:   else
rlm@1:   {
rlm@1:     if (!g_GlobalKeyCache.Find(_key))
rlm@1:     {
rlm@1:       _key.CalculateDigest();
rlm@1:       g_GlobalKeyCache.Add(_key);
rlm@1:     }
rlm@1:     _cachedKeys.Add(_key);
rlm@1:   }
rlm@1: }
rlm@1: 
rlm@1: #ifndef EXTRACT_ONLY
rlm@1: 
rlm@1: /*
rlm@1: STDMETHODIMP CEncoder::ResetSalt()
rlm@1: {
rlm@1:   _key.SaltSize = 4;
rlm@1:   g_RandomGenerator.Generate(_key.Salt, _key.SaltSize);
rlm@1:   return S_OK;
rlm@1: }
rlm@1: */
rlm@1: 
rlm@1: STDMETHODIMP CEncoder::ResetInitVector()
rlm@1: {
rlm@1:   _ivSize = 8;
rlm@1:   g_RandomGenerator.Generate(_iv, (unsigned)_ivSize);
rlm@1:   return S_OK;
rlm@1: }
rlm@1: 
rlm@1: STDMETHODIMP CEncoder::WriteCoderProperties(ISequentialOutStream *outStream)
rlm@1: {
rlm@1:    // _key.Init();
rlm@1:    for (UInt32 i = _ivSize; i < sizeof(_iv); i++)
rlm@1:     _iv[i] = 0;
rlm@1: 
rlm@1:   UInt32 ivSize = _ivSize;
rlm@1:   
rlm@1:   // _key.NumCyclesPower = 0x3F;
rlm@1:   _key.NumCyclesPower = 19;
rlm@1: 
rlm@1:   Byte firstByte = (Byte)(_key.NumCyclesPower |
rlm@1:     (((_key.SaltSize == 0) ? 0 : 1) << 7) |
rlm@1:     (((ivSize == 0) ? 0 : 1) << 6));
rlm@1:   RINOK(outStream->Write(&firstByte, 1, NULL));
rlm@1:   if (_key.SaltSize == 0 && ivSize == 0)
rlm@1:     return S_OK;
rlm@1:   Byte saltSizeSpec = (Byte)((_key.SaltSize == 0) ? 0 : (_key.SaltSize - 1));
rlm@1:   Byte ivSizeSpec = (Byte)((ivSize == 0) ? 0 : (ivSize - 1));
rlm@1:   Byte secondByte = (Byte)(((saltSizeSpec) << 4) | ivSizeSpec);
rlm@1:   RINOK(outStream->Write(&secondByte, 1, NULL));
rlm@1:   if (_key.SaltSize > 0)
rlm@1:   {
rlm@1:     RINOK(WriteStream(outStream, _key.Salt, _key.SaltSize));
rlm@1:   }
rlm@1:   if (ivSize > 0)
rlm@1:   {
rlm@1:     RINOK(WriteStream(outStream, _iv, ivSize));
rlm@1:   }
rlm@1:   return S_OK;
rlm@1: }
rlm@1: 
rlm@1: HRESULT CEncoder::CreateFilter()
rlm@1: {
rlm@1:   _aesFilter = new CAesCbcEncoder;
rlm@1:   return S_OK;
rlm@1: }
rlm@1: 
rlm@1: #endif
rlm@1: 
rlm@1: STDMETHODIMP CDecoder::SetDecoderProperties2(const Byte *data, UInt32 size)
rlm@1: {
rlm@1:   _key.Init();
rlm@1:   UInt32 i;
rlm@1:   for (i = 0; i < sizeof(_iv); i++)
rlm@1:     _iv[i] = 0;
rlm@1:   if (size == 0)
rlm@1:     return S_OK;
rlm@1:   UInt32 pos = 0;
rlm@1:   Byte firstByte = data[pos++];
rlm@1: 
rlm@1:   _key.NumCyclesPower = firstByte & 0x3F;
rlm@1:   if ((firstByte & 0xC0) == 0)
rlm@1:     return S_OK;
rlm@1:   _key.SaltSize = (firstByte >> 7) & 1;
rlm@1:   UInt32 ivSize = (firstByte >> 6) & 1;
rlm@1: 
rlm@1:   if (pos >= size)
rlm@1:     return E_INVALIDARG;
rlm@1:   Byte secondByte = data[pos++];
rlm@1:   
rlm@1:   _key.SaltSize += (secondByte >> 4);
rlm@1:   ivSize += (secondByte & 0x0F);
rlm@1:   
rlm@1:   if (pos + _key.SaltSize + ivSize > size)
rlm@1:     return E_INVALIDARG;
rlm@1:   for (i = 0; i < _key.SaltSize; i++)
rlm@1:     _key.Salt[i] = data[pos++];
rlm@1:   for (i = 0; i < ivSize; i++)
rlm@1:     _iv[i] = data[pos++];
rlm@1:   return S_OK;
rlm@1: }
rlm@1: 
rlm@1: STDMETHODIMP CBaseCoder::CryptoSetPassword(const Byte *data, UInt32 size)
rlm@1: {
rlm@1:   _key.Password.SetCapacity((size_t)size);
rlm@1:   memcpy(_key.Password, data, (size_t)size);
rlm@1:   return S_OK;
rlm@1: }
rlm@1: 
rlm@1: STDMETHODIMP CBaseCoder::Init()
rlm@1: {
rlm@1:   CalculateDigest();
rlm@1:   if (_aesFilter == 0)
rlm@1:   {
rlm@1:     RINOK(CreateFilter());
rlm@1:   }
rlm@1:   CMyComPtr<ICryptoProperties> cp;
rlm@1:   RINOK(_aesFilter.QueryInterface(IID_ICryptoProperties, &cp));
rlm@1:   RINOK(cp->SetKey(_key.Key, sizeof(_key.Key)));
rlm@1:   RINOK(cp->SetInitVector(_iv, sizeof(_iv)));
rlm@1:   return S_OK;
rlm@1: }
rlm@1: 
rlm@1: STDMETHODIMP_(UInt32) CBaseCoder::Filter(Byte *data, UInt32 size)
rlm@1: {
rlm@1:   return _aesFilter->Filter(data, size);
rlm@1: }
rlm@1: 
rlm@1: HRESULT CDecoder::CreateFilter()
rlm@1: {
rlm@1:   _aesFilter = new CAesCbcDecoder;
rlm@1:   return S_OK;
rlm@1: }
rlm@1: 
rlm@1: }}