diff options
Diffstat (limited to 'CPP/7zip/Crypto/7zAes.cpp')
-rwxr-xr-x | CPP/7zip/Crypto/7zAes.cpp | 245 |
1 files changed, 245 insertions, 0 deletions
diff --git a/CPP/7zip/Crypto/7zAes.cpp b/CPP/7zip/Crypto/7zAes.cpp new file mode 100755 index 00000000..3a1cbd68 --- /dev/null +++ b/CPP/7zip/Crypto/7zAes.cpp @@ -0,0 +1,245 @@ +// 7zAes.cpp + +#include "StdAfx.h" + +extern "C" +{ +#include "../../../C/Sha256.h" +} + +#include "Windows/Synchronization.h" +#include "../Common/StreamObjects.h" +#include "../Common/StreamUtils.h" +#include "7zAes.h" +#include "MyAes.h" + +#ifndef EXTRACT_ONLY +#include "RandGen.h" +#endif + +using namespace NWindows; + +namespace NCrypto { +namespace NSevenZ { + +bool CKeyInfo::IsEqualTo(const CKeyInfo &a) const +{ + if (SaltSize != a.SaltSize || NumCyclesPower != a.NumCyclesPower) + return false; + for (UInt32 i = 0; i < SaltSize; i++) + if (Salt[i] != a.Salt[i]) + return false; + return (Password == a.Password); +} + +void CKeyInfo::CalculateDigest() +{ + if (NumCyclesPower == 0x3F) + { + UInt32 pos; + for (pos = 0; pos < SaltSize; pos++) + Key[pos] = Salt[pos]; + for (UInt32 i = 0; i < Password.GetCapacity() && pos < kKeySize; i++) + Key[pos++] = Password[i]; + for (; pos < kKeySize; pos++) + Key[pos] = 0; + } + else + { + CSha256 sha; + Sha256_Init(&sha); + const UInt64 numRounds = UInt64(1) << (NumCyclesPower); + Byte temp[8] = { 0,0,0,0,0,0,0,0 }; + for (UInt64 round = 0; round < numRounds; round++) + { + Sha256_Update(&sha, Salt, (size_t)SaltSize); + Sha256_Update(&sha, Password, Password.GetCapacity()); + Sha256_Update(&sha, temp, 8); + for (int i = 0; i < 8; i++) + if (++(temp[i]) != 0) + break; + } + Sha256_Final(&sha, Key); + } +} + +bool CKeyInfoCache::Find(CKeyInfo &key) +{ + for (int i = 0; i < Keys.Size(); i++) + { + const CKeyInfo &cached = Keys[i]; + if (key.IsEqualTo(cached)) + { + for (int j = 0; j < kKeySize; j++) + key.Key[j] = cached.Key[j]; + if (i != 0) + { + Keys.Insert(0, cached); + Keys.Delete(i+1); + } + return true; + } + } + return false; +} + +void CKeyInfoCache::Add(CKeyInfo &key) +{ + if (Find(key)) + return; + if (Keys.Size() >= Size) + Keys.DeleteBack(); + Keys.Insert(0, key); +} + +static CKeyInfoCache g_GlobalKeyCache(32); +static NSynchronization::CCriticalSection g_GlobalKeyCacheCriticalSection; + +CBase::CBase(): + _cachedKeys(16), + _ivSize(0) +{ + for (int i = 0; i < sizeof(_iv); i++) + _iv[i] = 0; +} + +void CBase::CalculateDigest() +{ + NSynchronization::CCriticalSectionLock lock(g_GlobalKeyCacheCriticalSection); + if (_cachedKeys.Find(_key)) + g_GlobalKeyCache.Add(_key); + else + { + if (!g_GlobalKeyCache.Find(_key)) + { + _key.CalculateDigest(); + g_GlobalKeyCache.Add(_key); + } + _cachedKeys.Add(_key); + } +} + +#ifndef EXTRACT_ONLY + +/* +STDMETHODIMP CEncoder::ResetSalt() +{ + _key.SaltSize = 4; + g_RandomGenerator.Generate(_key.Salt, _key.SaltSize); + return S_OK; +} +*/ + +STDMETHODIMP CEncoder::ResetInitVector() +{ + _ivSize = 8; + g_RandomGenerator.Generate(_iv, (unsigned)_ivSize); + return S_OK; +} + +STDMETHODIMP CEncoder::WriteCoderProperties(ISequentialOutStream *outStream) +{ + // _key.Init(); + for (UInt32 i = _ivSize; i < sizeof(_iv); i++) + _iv[i] = 0; + + UInt32 ivSize = _ivSize; + + // _key.NumCyclesPower = 0x3F; + _key.NumCyclesPower = 19; + + Byte firstByte = (Byte)(_key.NumCyclesPower | + (((_key.SaltSize == 0) ? 0 : 1) << 7) | + (((ivSize == 0) ? 0 : 1) << 6)); + RINOK(outStream->Write(&firstByte, 1, NULL)); + if (_key.SaltSize == 0 && ivSize == 0) + return S_OK; + Byte saltSizeSpec = (Byte)((_key.SaltSize == 0) ? 0 : (_key.SaltSize - 1)); + Byte ivSizeSpec = (Byte)((ivSize == 0) ? 0 : (ivSize - 1)); + Byte secondByte = (Byte)(((saltSizeSpec) << 4) | ivSizeSpec); + RINOK(outStream->Write(&secondByte, 1, NULL)); + if (_key.SaltSize > 0) + { + RINOK(WriteStream(outStream, _key.Salt, _key.SaltSize)); + } + if (ivSize > 0) + { + RINOK(WriteStream(outStream, _iv, ivSize)); + } + return S_OK; +} + +HRESULT CEncoder::CreateFilter() +{ + _aesFilter = new CAesCbcEncoder; + return S_OK; +} + +#endif + +STDMETHODIMP CDecoder::SetDecoderProperties2(const Byte *data, UInt32 size) +{ + _key.Init(); + UInt32 i; + for (i = 0; i < sizeof(_iv); i++) + _iv[i] = 0; + if (size == 0) + return S_OK; + UInt32 pos = 0; + Byte firstByte = data[pos++]; + + _key.NumCyclesPower = firstByte & 0x3F; + if ((firstByte & 0xC0) == 0) + return S_OK; + _key.SaltSize = (firstByte >> 7) & 1; + UInt32 ivSize = (firstByte >> 6) & 1; + + if (pos >= size) + return E_INVALIDARG; + Byte secondByte = data[pos++]; + + _key.SaltSize += (secondByte >> 4); + ivSize += (secondByte & 0x0F); + + if (pos + _key.SaltSize + ivSize > size) + return E_INVALIDARG; + for (i = 0; i < _key.SaltSize; i++) + _key.Salt[i] = data[pos++]; + for (i = 0; i < ivSize; i++) + _iv[i] = data[pos++]; + return S_OK; +} + +STDMETHODIMP CBaseCoder::CryptoSetPassword(const Byte *data, UInt32 size) +{ + _key.Password.SetCapacity((size_t)size); + memcpy(_key.Password, data, (size_t)size); + return S_OK; +} + +STDMETHODIMP CBaseCoder::Init() +{ + CalculateDigest(); + if (_aesFilter == 0) + { + RINOK(CreateFilter()); + } + CMyComPtr<ICryptoProperties> cp; + RINOK(_aesFilter.QueryInterface(IID_ICryptoProperties, &cp)); + RINOK(cp->SetKey(_key.Key, sizeof(_key.Key))); + RINOK(cp->SetInitVector(_iv, sizeof(_iv))); + return S_OK; +} + +STDMETHODIMP_(UInt32) CBaseCoder::Filter(Byte *data, UInt32 size) +{ + return _aesFilter->Filter(data, size); +} + +HRESULT CDecoder::CreateFilter() +{ + _aesFilter = new CAesCbcDecoder; + return S_OK; +} + +}} |