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Unicode C

AES OFB Output Feedback Mode Encryption

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

Chilkat Unicode C Downloads

Unicode C
#include <C_CkCrypt2W.h>

void ChilkatSample(void)
    {
    HCkCrypt2W crypt;
    const wchar_t *ivHex;
    const wchar_t *keyHex;
    const wchar_t *encStr;
    HCkCrypt2W decrypt;
    const wchar_t *decStr;

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

    crypt = CkCrypt2W_Create();

    CkCrypt2W_putCryptAlgorithm(crypt,L"aes");
    // Set the cipher mode to Output Feedback
    CkCrypt2W_putCipherMode(crypt,L"ofb");
    CkCrypt2W_putKeyLength(crypt,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.
    CkCrypt2W_putEncodingMode(crypt,L"hex");

    ivHex = L"000102030405060708090A0B0C0D0E0F";
    CkCrypt2W_SetEncodedIV(crypt,ivHex,L"hex");

    // The secret key must equal the size of the key.  For
    // 256-bit encryption, the binary secret key is 32 bytes.
    keyHex = L"603deb1015ca71be2b73aef0857d77811f352c073b6108d72d9810a30914dff4";
    CkCrypt2W_SetEncodedKey(crypt,keyHex,L"hex");

    // Encrypt a string...
    encStr = CkCrypt2W_encryptStringENC(crypt,L"Popular opinions, on subjects not palpable to sense, are often true, but seldom or never the whole truth. -- John Stuart Mill");
    wprintf(L"%s\n",encStr);

    decrypt = CkCrypt2W_Create();
    CkCrypt2W_putCryptAlgorithm(decrypt,L"aes");
    CkCrypt2W_putCipherMode(decrypt,L"ofb");
    CkCrypt2W_putKeyLength(decrypt,256);
    CkCrypt2W_putEncodingMode(decrypt,L"hex");
    CkCrypt2W_SetEncodedIV(decrypt,ivHex,L"hex");
    CkCrypt2W_SetEncodedKey(decrypt,keyHex,L"hex");

    // Now decrypt:
    decStr = CkCrypt2W_decryptStringENC(decrypt,encStr);
    wprintf(L"%s\n",decStr);


    CkCrypt2W_Dispose(crypt);
    CkCrypt2W_Dispose(decrypt);

    }