(MFC) AES OFB Output Feedback Mode Encryption

Demonstrates how to encrypt using AES OFB (Output Feedback) mode.

Chilkat C/C++ Library Downloads MS Visual C/C++ Libs

See Also: Using MFC CString in Chilkat

#include <CkCrypt2.h>

void ChilkatSample(void)
    {
    CkString strOut;

    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    CkCrypt2 crypt;

    crypt.put_CryptAlgorithm("aes");
    // Set the cipher mode to Output Feedback
    crypt.put_CipherMode("ofb");
    crypt.put_KeyLength(256);

    // EncodingMode specifies the encoding of the output for
    // encryption, and the input for decryption.
    // It may be "hex", "url", "base64", "quoted-printable", or many other choices.
    crypt.put_EncodingMode("hex");

    const char *ivHex = "000102030405060708090A0B0C0D0E0F";
    crypt.SetEncodedIV(ivHex,"hex");

    // The secret key must equal the size of the key.  For
    // 256-bit encryption, the binary secret key is 32 bytes.
    const char *keyHex = "603deb1015ca71be2b73aef0857d77811f352c073b6108d72d9810a30914dff4";
    crypt.SetEncodedKey(keyHex,"hex");

    // Encrypt a string...
    const char *encStr = crypt.encryptStringENC("Popular opinions, on subjects not palpable to sense, are often true, but seldom or never the whole truth. -- John Stuart Mill");
    strOut.append(encStr);
    strOut.append("\r\n");

    CkCrypt2 decrypt;
    decrypt.put_CryptAlgorithm("aes");
    decrypt.put_CipherMode("ofb");
    decrypt.put_KeyLength(256);
    decrypt.put_EncodingMode("hex");
    decrypt.SetEncodedIV(ivHex,"hex");
    decrypt.SetEncodedKey(keyHex,"hex");

    // Now decrypt:
    const char *decStr = decrypt.decryptStringENC(encStr);
    strOut.append(decStr);
    strOut.append("\r\n");


    SetDlgItemText(IDC_EDIT1,strOut.getUnicode());

    }