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This commit is contained in:
Igor Pavlov
2005-05-30 00:00:00 +00:00
committed by Kornel Lesiński
parent 8c1b5c7b7e
commit 3c510ba80b
926 changed files with 40559 additions and 23519 deletions
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30
7zip/Crypto/Zip/ZipCrypto.cpp
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@@ -3,60 +3,60 @@
#include "StdAfx.h"
#include "ZipCipher.h"
#include "Common/Crc.h"
#include "../../../Common/CRC.h"
namespace NCrypto {
namespace NZip {
inline UINT32 CRC32(UINT32 c, BYTE b)
static inline UInt32 ZipCRC32(UInt32 c, Byte b)
{
return CCRC::Table[(c ^ b) & 0xFF] ^ (c >> 8);
}
void CCipher::UpdateKeys(BYTE b)
void CCipher::UpdateKeys(Byte b)
{
Keys[0] = CRC32(Keys[0], b);
Keys[0] = ZipCRC32(Keys[0], b);
Keys[1] += Keys[0] & 0xff;
Keys[1] = Keys[1] * 134775813L + 1;
Keys[2] = CRC32(Keys[2], Keys[1] >> 24);
Keys[2] = ZipCRC32(Keys[2], Keys[1] >> 24);
}
void CCipher::SetPassword(const BYTE *password, UINT32 passwordLength)
void CCipher::SetPassword(const Byte *password, UInt32 passwordLength)
{
Keys[0] = 305419896L;
Keys[1] = 591751049L;
Keys[2] = 878082192L;
for (UINT32 i = 0; i < passwordLength; i++)
for (UInt32 i = 0; i < passwordLength; i++)
UpdateKeys(password[i]);
}
BYTE CCipher::DecryptByteSpec()
Byte CCipher::DecryptByteSpec()
{
UINT32 temp = Keys[2] | 2;
UInt32 temp = Keys[2] | 2;
return (temp * (temp ^ 1)) >> 8;
}
BYTE CCipher::DecryptByte(BYTE encryptedByte)
Byte CCipher::DecryptByte(Byte encryptedByte)
{
BYTE c = encryptedByte ^ DecryptByteSpec();
Byte c = encryptedByte ^ DecryptByteSpec();
UpdateKeys(c);
return c;
}
BYTE CCipher::EncryptByte(BYTE b)
Byte CCipher::EncryptByte(Byte b)
{
BYTE c = b ^ DecryptByteSpec();
Byte c = b ^ DecryptByteSpec();
UpdateKeys(b);
return c;
}
void CCipher::DecryptHeader(BYTE *buffer)
void CCipher::DecryptHeader(Byte *buffer)
{
for (int i = 0; i < 12; i++)
buffer[i] = DecryptByte(buffer[i]);
}
void CCipher::EncryptHeader(BYTE *buffer)
void CCipher::EncryptHeader(Byte *buffer)
{
for (int i = 0; i < 12; i++)
buffer[i] = EncryptByte(buffer[i]);