AESEncryption.cpp

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//
//    (C) Copyright 2011 EaseFilter Technologies Inc.
//    All Rights Reserved
//
//    This software is part of a licensed software product and may
//    only be used or copied in accordance with the terms of that license.
//

#include "stdafx.h"
#include "tools.h"
#include "FilterAPI.h"

WCHAR* testFolder = L"c:\\filterTest";
WCHAR* testFile = L"c:\\filterTest\\testEncryptfile1.bin";
WCHAR* copyFile = L"c:\\filterTest\\testEncryptfile1.copy.bin";

//Add clear text data to the file.
unsigned char iv[] = {0xf0,0xf1,0xf2,0xf3,0xf4,0xf5,0xf6,0xf7,0xf8,0xf9,0xfa,0xfb,0xfc,0xfd,0xfe,0xff};// Initialization vector
unsigned char clearText[] = {0x6b,0xc1,0xbe,0xe2,0x2e,0x40,0x9f,0x96,0xe9,0x3d,0x7e,0x11,0x73,0x93,0x17,0x2a};// clear text

//256 bit test key
unsigned char key[] = {0x60,0x3d,0xeb,0x10,0x15,0xca,0x71,0xbe,0x2b,0x73,0xae,0xf0,0x85,0x7d,0x77,0x81,0x1f,0x35,0x2c,0x07,0x3b,0x61,0x08,0xd7,0x2d,0x98,0x10,0xa3,0x09,0x14,0xdf,0xf4};// 32bytes encrytpion key
unsigned char cipherText[] = {0x60,0x1e,0xc3,0x13,0x77,0x57,0x89,0xa5,0xb7,0xa7,0xf5,0x04,0xbb,0xf3,0xd2,0x28};// cipher text
    

BOOL
CreateTestFile(BOOL bypassFilterDriver )
{
    LARGE_INTEGER ByteOffset = {0};
    OVERLAPPED Overlapped = {0};
    DWORD dwTransferred = 0;
    int nError = ERROR_SUCCESS;
    BOOL ret = FALSE;
    DWORD dwFlagsAndAttributes = FILE_FLAG_NO_BUFFERING;

    //Create the test folder.
    ret = CreateDirectory(testFolder,NULL);

    if( ret == 0 )
    {
        nError = GetLastError();
        if( nError != ERROR_ALREADY_EXISTS )
        {
            PrintErrorMessage(L"Create test folder failed.", nError);
            return FALSE;
        }
    }

    if( bypassFilterDriver )
    {
        dwFlagsAndAttributes |= FILE_ATTRIBUTE_REPARSE_POINT|
                                FILE_FLAG_OPEN_REPARSE_POINT|FILE_FLAG_NO_BUFFERING|FILE_FLAG_OPEN_NO_RECALL;
    }

    //Create the test file,if it exist, overwrite it.
    HANDLE pFile = CreateFile(testFile,GENERIC_WRITE,NULL,NULL,CREATE_ALWAYS,dwFlagsAndAttributes,NULL);

    if( pFile == INVALID_HANDLE_VALUE )
    {
        PrintErrorMessage(L"Create test file failed.", GetLastError());
        return FALSE;
    }

    //since we open the file without buffering,we need to write the file with sector align length
    DWORD bufferLength = 65536;
    unsigned char* buffer = (unsigned char*)_aligned_malloc(bufferLength,bufferLength);
    if( NULL == buffer )
    {
        ret = FALSE;
        PrintErrorMessage(L"Allocate memory failed with insufficient resources.",0);
        goto EXIT;
    }

    ZeroMemory(buffer,65536);

    RtlCopyMemory(buffer,clearText,sizeof(clearText));

    // Write test data to the test file.
    if(!WriteFile(pFile, buffer,bufferLength, &dwTransferred, NULL))
    {
        nError = GetLastError();
        PrintErrorMessage(L"WriteFile failed.", nError);
        ret = FALSE;
        goto EXIT;
    }

    SetFileSize(pFile,sizeof(clearText));

    ret = TRUE;

EXIT:

    CloseHandle(pFile);

    if( buffer != NULL )
    {
        _aligned_free( buffer);
    }

    return ret;

}

BOOL
VerifyRawData(BOOL isEncrypted)
{
    HANDLE pFile = INVALID_HANDLE_VALUE;

    ULONG ivLength = 16;
    BYTE ivTag[16];
    BOOL ret = FALSE;

    if(isEncrypted )
    {
         ret = GetIVTag(testFile,&ivLength,ivTag);
        if(!ret)
        {
            PrintLastErrorMessage( L"121 VerifyRawData GetIVTag failed.");
            return FALSE;
        }   
    }

    //open test file bypass the filter driver.
    pFile = CreateFile( testFile,
                        GENERIC_READ,NULL,NULL,
                        OPEN_EXISTING,
                        FILE_ATTRIBUTE_ENCRYPTED|FILE_ATTRIBUTE_REPARSE_POINT|
                        FILE_FLAG_OPEN_REPARSE_POINT|FILE_FLAG_NO_BUFFERING|FILE_FLAG_OPEN_NO_RECALL,
                        NULL);

    if( pFile == INVALID_HANDLE_VALUE )
    {
        PrintErrorMessage(L"Open test file failed.", GetLastError());
        return FALSE;
    }

    //since we open the file without buffering,we need to read the file with sector align length
    DWORD bufferLength = 65536;
    unsigned char* buffer = (unsigned char*)_aligned_malloc(bufferLength,bufferLength);
    if( NULL == buffer )
    {
        ret = FALSE;
        PrintErrorMessage(L"Allocate memory failed with insufficient resources.",0);
        goto EXIT;
    }

    ret = ReadFile(pFile,buffer,bufferLength,&bufferLength,NULL);
    if(0 == ret)
    {
        PrintErrorMessage(L"Read test file failed.",GetLastError());
        goto EXIT;
    }

    if( isEncrypted && ivLength == 0)
    {
        ret = FALSE;
        PrintErrorMessage(L"VerifyRawData failed, the encrypted file doesn't have iv tag.",0);
        goto EXIT;
    }
    
    if( isEncrypted )
    {
        if( memcmp(buffer,cipherText,bufferLength) == 0)
        {
            ret = TRUE;
        }
        else
        {
            printf("Compare encrypted data failed.\r\nCipher data:");
            for(int i = 0; i < sizeof(cipherText); i++)
            {
                printf("%2x",cipherText[i]);
            }

            printf("\r\nRaw data:");
            for(int i = 0; i < sizeof(cipherText); i++)
            {
                printf("%2x",buffer[i]);
            }

            printf("\r\n");

            ret = FALSE;
        }
    }
    else
    {
        if( memcmp(buffer,clearText,bufferLength) == 0)
        {
            ret = TRUE;
        }
        else
        {
            printf("Compare decrypted data failed.\r\nClear data:");
            for(int i = 0; i < sizeof(clearText); i++)
            {
                printf("%2x",clearText[i]);
            }

            printf("\r\nRaw data:");
            for(int i = 0; i < sizeof(clearText); i++)
            {
                printf("%2x",buffer[i]);
            }

            printf("\r\n");

            ret = FALSE;
        }
    }

EXIT:
    
    if( pFile != INVALID_HANDLE_VALUE )
    {
        CloseHandle(pFile);
    }

    if( buffer != NULL )
    {
        _aligned_free( buffer);
    }


    return ret;

}

BOOL
CopyEncryptedFile()
{
    HANDLE pFile = INVALID_HANDLE_VALUE;
    HANDLE pFile2 = INVALID_HANDLE_VALUE;
    BOOL ret = FALSE;
    ULONG ivLength = 16;
    BYTE ivTag[16];
    unsigned char* buffer = NULL;
    
    ret = GetIVTag(testFile,&ivLength,ivTag);
    if(!ret)
    {
        PrintLastErrorMessage(L"GetIVTag failed.");
        return FALSE;
    }

    if( ivLength == 0 )
    {
        PrintErrorMessage(L"The file is not encrypted.",0);
        return FALSE;
    }

    //open test file bypass the filter driver.
    pFile = CreateFile( testFile,
                        GENERIC_READ,NULL,NULL,
                        OPEN_EXISTING,
                        FILE_ATTRIBUTE_ENCRYPTED|FILE_ATTRIBUTE_REPARSE_POINT|
                        FILE_FLAG_OPEN_REPARSE_POINT|FILE_FLAG_NO_BUFFERING|FILE_FLAG_OPEN_NO_RECALL,
                        NULL);

    if( pFile == INVALID_HANDLE_VALUE )
    {
        PrintErrorMessage(L"Open test file failed.", GetLastError());
        return FALSE;
    }

    LARGE_INTEGER fileSize;
    if( !GetFileSizeEx(pFile,&fileSize))
    {
        PrintErrorMessage(L"Get test file size failed.", GetLastError());
        ret = FALSE;
        goto EXIT;
    }

    //Create test file bypass the filter driver.
    pFile2 = CreateFile( copyFile,
                        GENERIC_WRITE,NULL,NULL,
                        CREATE_ALWAYS,
                        FILE_ATTRIBUTE_ENCRYPTED|FILE_ATTRIBUTE_REPARSE_POINT|
                        FILE_FLAG_OPEN_REPARSE_POINT|FILE_FLAG_NO_BUFFERING|FILE_FLAG_OPEN_NO_RECALL,
                        NULL);

    if( pFile2 == INVALID_HANDLE_VALUE )
    {
        PrintErrorMessage(L"Create test copy file failed.", GetLastError());
        return FALSE;
    }

    DWORD dwTransferred = 0;
    DWORD bufferLength = 65536;
    buffer = (unsigned char*)_aligned_malloc(bufferLength,bufferLength);
    if( NULL == buffer )
    {
        ret = FALSE;
        PrintErrorMessage(L"Allocate memory failed with insufficient resources.",0);
        goto EXIT;
    }

    ZeroMemory(buffer,65536);

    ret = ReadFile(pFile,buffer,bufferLength,&dwTransferred,NULL);
    if(0 == ret)
    {
        PrintErrorMessage(L"Read test file failed.",GetLastError());
        goto EXIT;
    }       

    // Write test data to the test file.
    if(!WriteFile(pFile2, buffer, bufferLength, &dwTransferred, NULL))
    {
        PrintErrorMessage(L"WriteFile failed.", GetLastError());
        ret = FALSE;
        goto EXIT;
    }

    //set back the correct file size 
    ret = SetFileSize(pFile2,fileSize.QuadPart);
    if(!ret)
    {
        PrintLastErrorMessage( L"SetFileSize failed.");
    }

    if(pFile2 != INVALID_HANDLE_VALUE)
    {
        CloseHandle(pFile2);
    }

    //add the iv tag to the encrypted file, or the filter driver can't recognize the encrypted file.
    ret = AddIVTag(copyFile,ivLength,ivTag);
    if(!ret)
    {
        PrintLastErrorMessage( L"AddIVTag failed.");
    }

EXIT:

    if(pFile != INVALID_HANDLE_VALUE)
    {
        CloseHandle(pFile);
    }

    if(pFile2 != INVALID_HANDLE_VALUE)
    {
        CloseHandle(pFile2);
    }

    if( buffer != NULL )
    {
        _aligned_free( buffer);
    }

    return ret;
}

BOOL
VerifyFilterDriverDecryptData()
{
    BOOL ret = FALSE;
    HANDLE pFile = INVALID_HANDLE_VALUE;

    pFile = CreateFile( copyFile,
                        GENERIC_READ,NULL,NULL,
                        OPEN_EXISTING,
                        FILE_ATTRIBUTE_NORMAL,
                        NULL);
    
    if( pFile == INVALID_HANDLE_VALUE )
    {
        PrintErrorMessage(L"Open encrypted file failed.", GetLastError());
        return FALSE;
    }

    DWORD bufferLength = 65536;
    unsigned char* buffer = (unsigned char*)_aligned_malloc(bufferLength,bufferLength);
    if( NULL == buffer )
    {
        ret = FALSE;
        PrintErrorMessage(L"Allocate memory failed with insufficient resources.",0);
        goto EXIT;
    }

    ZeroMemory(buffer,65536);

    ret = ReadFile(pFile,buffer,bufferLength,&bufferLength,NULL);
    if(0 == ret)
    {
        PrintErrorMessage(L"Read test file failed.",GetLastError());
        goto EXIT;
    }

    if( memcmp(buffer,clearText,bufferLength) == 0)
    {
        ret = TRUE;
    }
    else
    {
        printf("Verified filter driver decryption data failed.\r\nclearText data:");
        for(int i = 0; i < sizeof(clearText); i++)
        {
            printf("%2x",clearText[i]);
        }

        printf("\r\nReturn data:");
        for(int i = 0; i < sizeof(clearText); i++)
        {
            printf("%2x",buffer[i]);
        }

        printf("\r\n");

        ret = FALSE;

    }

EXIT:
    
    if( pFile != INVALID_HANDLE_VALUE )
    {
        CloseHandle(pFile);
    }

    if( buffer != NULL )
    {
        _aligned_free( buffer);
    }


    return ret;

}

VOID
EncryptionUnitTest()
{
    DeleteFile(testFile);
    DeleteFile(copyFile);

    //create a new test file
    if(!CreateTestFile(TRUE))
    {
        return;
    }
    else
    {
        PrintPassedMessage(L"Created test file passed.\n");
    }
    
    if(!AESEncryptFile(testFile,sizeof(key),key,sizeof(iv),iv,TRUE))
    {
        PrintLastErrorMessage( L"447 AESEncryptFile failed.");
        return;
    }
    else
    {
        PrintPassedMessage(L"452 Encrypted test file passed.\n");
    }

    if(!VerifyRawData(TRUE))
    {
        PrintFailedMessage(L"457 Verified AESEncryptFile test failed.\n");
        return;
    }
    else
    {
        PrintPassedMessage(L"462 Verified encrypted file data passed.\n");
    }

    if(!CopyEncryptedFile())
    {
        return;
    }
    else
    {
        PrintPassedMessage(L"471 Copied encrypted file passed.\n");
    }

    if(!AESDecryptFile(testFile,sizeof(key),key,sizeof(iv),iv))
    {
        PrintLastErrorMessage( L"476 AESDecryptFile failed.");
        return;
    }
    else
    {
        PrintPassedMessage(L"481 Decrypted file passed.\n");
    }

    if(!VerifyRawData(FALSE))
    {
        PrintFailedMessage(L"486 Verified AESDecryptFile test failed.\n");
        return;
    }
    else
    {
        PrintPassedMessage(L"491 Verified decrypted file data passed.\n");
    }

    if(!VerifyFilterDriverDecryptData())
    {
        PrintFailedMessage(L"496 Verified filter driver decryption test failed.\n");
        return;
    }
    else
    {
        PrintPassedMessage(L"501 Verified filter driver decryption test passed.\n");
    }


    //create a new test file
    //test the filter driver encrypt the file, the filter driver should be enabled, and didn't exclude the current process Id.
    if(!CreateTestFile(FALSE))
    {
        PrintFailedMessage(L"513 Created encrypted test file with filter driver failed.\n");
        return;
    }
    else
    {
        PrintPassedMessage(L"518 Created encrypted test file with filter driver passed.\n");
    }

    //decrypt the filter driver encrypted file with decryption API
    if(!AESDecryptFile(testFile,sizeof(key),key,0,NULL))
    {
        PrintLastErrorMessage( L"538 AESDecryptFile filter driver encrypted file failed.");
        return;
    }
    
    if(!VerifyRawData(FALSE))
    {
        PrintFailedMessage(L"548 Verified filter driver encryption test failed.\n");
        return;
    }
    else
    {
        PrintPassedMessage(L"553 Verified filter driver encryption test passed.\n");
    }

    PrintPassedMessage(L"Encryption unit test passed.\n");
    wprintf(L"\r\n");

}