www.pudn.com > EncryptionDecryption.rar.rar > cipherappui.cpp

/* Copyright (c) 2003, Nokia. All rights reserved */ 
 
#include  
#include   
#include  
#include  
#include  
 
#include  
 
#include "Cipher.pan" 
#include "CipherAppUi.h" 
#include "CipherAppView.h" 
#include "Cipher.hrh" 
 
// Maximum length of the password 
const TInt KAknExQueryTextBufLength = 24; 
 
// Maximum length of the key data 
const TInt KMaxKeyDataLength = 2024; 
 
// Maximum length of the message 
const TInt KMaxPlainTextDataLength = 1012; 
 
// Location of the encrypted file 
_LIT(KCipherFilePath,"\\system\\apps\\cipher\\cipher.enc"); 
_LIT(KCipherDir,"\\system\\apps\\cipher\\"); 
 
// ConstructL is called by the application framework 
void CCipherAppUi::ConstructL() 
    { 
    BaseConstructL(); 
    iAppView = CCipherAppView::NewL(ClientRect()); 
    iAppView->SetMopParent(this); 
    AddToStackL(iAppView); 
    } 
 
CCipherAppUi::CCipherAppUi()                               
    { 
    // No implementation required 
    } 
 
CCipherAppUi::~CCipherAppUi() 
    { 
    if (iAppView) 
        { 
        iEikonEnv->RemoveFromStack(iAppView); 
        delete iAppView; 
        iAppView = NULL; 
        } 
    } 
 
 
void CCipherAppUi::HandleCommandL(TInt aCommand) 
    { 
    switch(aCommand) 
        { 
        case EEikCmdExit: 
        case EAknSoftkeyExit: 
            Exit(); 
            break; 
 
        case ECipherEncrypt: 
            EncryptL(); 
            break; 
 
        case ECipherDecrypt: 
            DecryptL(); 
            break; 
 
        default: 
            Panic(ECipherBasicUi); 
            break; 
        } 
    } 
 
 
void CCipherAppUi::EncryptL() 
    { 
    // Query the user for the password and text 
    TBuf textToEncrypt; 
    TBuf password; 
     
    CAknMultiLineDataQueryDialog* dlg =  
        CAknMultiLineDataQueryDialog::NewL(textToEncrypt, password); 
    if (!dlg->ExecuteLD(R_DIALOG_TEXT_PASSWORD_QUERY)) 
		{ 
        return; 
		} 
 
    // Create a file to write the cipher text to 
    RFs fileSession; 
    User::LeaveIfError(fileSession.Connect()); 
    CleanupClosePushL(fileSession); 
    fileSession.MkDir(KCipherDir); // Ignore return value 
    RFile file; 
    if (file.Replace(fileSession, KCipherFilePath, EFileWrite) != KErrNone) 
        { 
        CAknInformationNote* informationNote = new (ELeave)CAknInformationNote; 
 
        _LIT(KCreateFailedMessage,"Failed to create cipher.enc"); 
        informationNote->ExecuteLD(KCreateFailedMessage); 
        CleanupStack::PopAndDestroy(); // Close fileSession 
        return; 
        } 
    CleanupClosePushL(file); 
 
    // Set up the encryption engine with the user supplied password 
    CBoundedSecurityBase* encrypter = Security::NewL(); 
    CleanupStack::PushL(encrypter); 
    encrypter->SetL(KNullDesC, password); 
 
    // Write the security data, used in the decryption process to 
    // verify the password 
    RFileWriteStream outputFileStream(file); 
    CleanupClosePushL(outputFileStream); 
    outputFileStream << encrypter->SecurityData(); // Must use streaming api not WriteL 
 
    // Write the encrypted data 
    REncryptStream encryptedFileStream; 
    encryptedFileStream.AttachLC(outputFileStream, *encrypter, KNullDesC8);  
    encryptedFileStream << textToEncrypt; 
    encryptedFileStream.Close(); 
    encryptedFileStream.Pop(); 
 
    // Clean up 
    CleanupStack::PopAndDestroy(); // Close outputFileStream 
    CleanupStack::PopAndDestroy(encrypter);  
    CleanupStack::PopAndDestroy(); // Close file  
    CleanupStack::PopAndDestroy(); // Close fileSession 
     
    _LIT(KEncryptedText,"Encrypted text:"); 
    iAppView->PrintLineL(KEncryptedText); 
 
    iAppView->PrintLineL(textToEncrypt); 
 
    _LIT(KToFile,"to file cipher.enc"); 
    iAppView->PrintLineL(KToFile); 
    } 
 
void CCipherAppUi::DecryptL() 
    { 
    // Query the user for the password 
    TBuf password; 
    CAknTextQueryDialog* dlg =  
        new (ELeave) CAknTextQueryDialog(password, CAknQueryDialog::ENoTone); 
    if (! dlg->ExecuteLD(R_DIALOG_PASSWORD_QUERY)) 
    { 
        return; 
    } 
 
    // Open file containing encrypted data 
    RFs fileSession; 
    User::LeaveIfError(fileSession.Connect()); 
    CleanupClosePushL(fileSession); 
    RFile file; 
    User::LeaveIfError(file.Open(fileSession, KCipherFilePath, EFileRead)); 
    CleanupClosePushL(file); 
 
    RFileReadStream inputFileStream(file); 
    CleanupClosePushL(inputFileStream); 
 
    // Read the security data  
    HBufC8* securityData = HBufC8::NewLC(inputFileStream, KMaxKeyDataLength); 
 
    // Create security object, using the read security data 
    CBoundedSecurityBase* decrypter = Security::NewL(*securityData);  
    CleanupStack::PushL(decrypter); 
 
    // Authenticate password 
    TRAPD(err, decrypter->PrepareL(password)); 
    if (err != KErrNone) 
        { 
        CAknInformationNote* informationNote = new (ELeave)CAknInformationNote; 
 
        _LIT(KPasswdFailedMessage,"Failed to verify password!"); 
        informationNote->ExecuteLD(KPasswdFailedMessage); 
        } 
    else  
        { 
        // Read the encrypted data 
        RDecryptStream decryptedFileStream; 
        decryptedFileStream.AttachLC(inputFileStream, *decrypter, KNullDesC8);  
        CleanupClosePushL(decryptedFileStream); 
        HBufC* decryptedData = HBufC::NewLC(decryptedFileStream, KMaxPlainTextDataLength); 
 
        _LIT(KDecryptedMessage,"Decrypted cipher.enc"); 
        _LIT(KContentsMessage,"Contents:"); 
        iAppView->PrintLineL(KDecryptedMessage); 
        iAppView->PrintLineL(KContentsMessage); 
        iAppView->PrintLineL(*decryptedData); 
 
        CleanupStack::PopAndDestroy(decryptedData); 
        CleanupStack::PopAndDestroy(); // Close decryptedFileStream 
        decryptedFileStream.Pop(); // Removes item placed on cleanup stack by AttachLC 
        } 
 
    CleanupStack::PopAndDestroy(decrypter); 
    CleanupStack::PopAndDestroy(securityData); 
 
    CleanupStack::PopAndDestroy(); // Close inputFileStream  
    CleanupStack::PopAndDestroy(); // Close file  
    CleanupStack::PopAndDestroy(); // Close fileSession 
    }