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C

RSA OAEP Padding

See more RSA Examples

Demonstrates how to use OAEP padding with the RSA encryption algorithm. More information about OAEP Padding.

Chilkat C Downloads

C
#include <C_CkRsa.h>
#include <C_CkPublicKey.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkRsa rsa;
    const char *pubKeyXml;
    HCkPublicKey pubKey;
    const char *plainText;
    BOOL usePrivateKey;
    const char *encryptedStr;

    success = FALSE;

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

    rsa = CkRsa_Create();

    // RSA public key in XML format:
    pubKeyXml = "<RSAPublicKey><Modulus>of3im3mRgd2NLXIGoK6uYLg6jj0Ug2b42rnqa5Tbwz2ieFqMJqt+++x2oqLYGurlz49nt+7/785g3XYWqoka4u9c9zul6YubIjnBM72dQy7rEkEfbUxgjcxqXyjZFx+FpaxFUecLu688XEu+9UA42VKiCgcl+E7TrqnfeeYpNXc=</Modulus><Exponent>AQAB</Exponent></RSAPublicKey>";

    pubKey = CkPublicKey_Create();
    success = CkPublicKey_LoadFromString(pubKey,pubKeyXml);
    if (success == FALSE) {
        printf("%s\n",CkPublicKey_lastErrorText(pubKey));
        CkRsa_Dispose(rsa);
        CkPublicKey_Dispose(pubKey);
        return;
    }

    success = CkRsa_UsePublicKey(rsa,pubKey);
    if (success == FALSE) {
        printf("%s\n",CkRsa_lastErrorText(rsa));
        CkRsa_Dispose(rsa);
        CkPublicKey_Dispose(pubKey);
        return;
    }

    // To use Optimal Asymmetric Encryption Padding (OAEP) padding,
    // simply set the PkcsPadding property to FALSE
    CkRsa_putPkcsPadding(rsa,FALSE);

    // Encrypt a string and return the encrypted data base64-encoded:
    CkRsa_putEncodingMode(rsa,"base64");

    plainText = "RSA Encryption should be easy.";

    usePrivateKey = FALSE;
    encryptedStr = CkRsa_encryptStringENC(rsa,plainText,usePrivateKey);
    printf("%s\n",encryptedStr);


    CkRsa_Dispose(rsa);
    CkPublicKey_Dispose(pubKey);

    }