C

AES Encryption

See more Encryption Examples

AES encryption. The Chilkat encryption component supports 128-bit, 192-bit, and 256-bit AES encryption in ECB (Electronic Cookbook), CBC (Cipher-Block Chaining), and other modes. C

#include <C_CkCrypt2.h>

void ChilkatSample(void)
    {
    HCkCrypt2 crypt;
    const char *ivHex;
    const char *keyHex;
    const char *encStr;
    const char *decStr;

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

    crypt = CkCrypt2_Create();

    // AES is also known as Rijndael.		
    CkCrypt2_putCryptAlgorithm(crypt,"aes");

    // CipherMode may be "ecb", "cbc", "ofb", "cfb", "gcm", etc.
    // Note: Check the online reference documentation to see the Chilkat versions
    // when certain cipher modes were introduced.
    CkCrypt2_putCipherMode(crypt,"cbc");

    // KeyLength may be 128, 192, 256
    CkCrypt2_putKeyLength(crypt,256);

    // The padding scheme determines the contents of the bytes
    // that are added to pad the result to a multiple of the
    // encryption algorithm's block size.  AES has a block
    // size of 16 bytes, so encrypted output is always
    // a multiple of 16.
    CkCrypt2_putPaddingScheme(crypt,0);

    // EncodingMode specifies the encoding of the output for
    // encryption, and the input for decryption.
    // It may be "hex", "url", "base64", or "quoted-printable".
    CkCrypt2_putEncodingMode(crypt,"hex");

    // An initialization vector is required if using CBC mode.
    // ECB mode does not use an IV.
    // The length of the IV is equal to the algorithm's block size.
    // It is NOT equal to the length of the key.
    ivHex = "000102030405060708090A0B0C0D0E0F";
    CkCrypt2_SetEncodedIV(crypt,ivHex,"hex");

    // The secret key must equal the size of the key.  For
    // 256-bit encryption, the binary secret key is 32 bytes.
    // For 128-bit encryption, the binary secret key is 16 bytes.
    keyHex = "000102030405060708090A0B0C0D0E0F101112131415161718191A1B1C1D1E1F";
    CkCrypt2_SetEncodedKey(crypt,keyHex,"hex");

    // Encrypt a string...
    // The input string is 44 ANSI characters (i.e. 44 bytes), so
    // the output should be 48 bytes (a multiple of 16).
    // Because the output is a hex string, it should
    // be 96 characters long (2 chars per byte).
    encStr = CkCrypt2_encryptStringENC(crypt,"The quick brown fox jumps over the lazy dog.");
    printf("%s\n",encStr);

    // This is the encrypted output in hex format:
    // 4846F83AA211E239AA62A21F527F089EE9DDBEAD30EE15D4E79B607A621B97BEDB9B6F00A9B21F1B43A50B4C1BE0EDF2

    // Now decrypt:
    decStr = CkCrypt2_decryptStringENC(crypt,encStr);
    printf("%s\n",decStr);

    // This is the decrypted string:
    // The quick brown fox jumps over the lazy dog.


    CkCrypt2_Dispose(crypt);

    }