C

RSA Encrypt with Modulus and Exponent

See more RSA Examples

Demonstrates how to RSA encrypt with a given modulus and exponent. C

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

void ChilkatSample(void)
    {
    BOOL success;
    HCkRsa rsa;
    const char *modulus;
    const char *exponent;
    HCkXml xml;
    HCkPublicKey pubKey;
    BOOL usePrivateKey;
    const char *plainText;
    const char *encryptedStrBase64;

    success = FALSE;

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

    rsa = CkRsa_Create();

    // Assuming you already have a base64 modulus and exponent,
    // wrap it in XML like this:
    modulus = "qMBRpdYrAy5aMmo31NErUizh5sbweguSmh4wlK6uJEIDl+kwTlROnE34KOFExeTbJSX0WygPi+vWl0yNq7buIMUKpytossAAWut5khO3CQJxTk7G2gnEPNUUXHiExGgNrLzcSLv8YIlfVALhoRWyC67KOL+a+3taNq3h+BHeWhM=";
    exponent = "AQAB";

    xml = CkXml_Create();
    CkXml_putTag(xml,"RSAPublicKey");
    CkXml_NewChild2(xml,"Modulus",modulus);
    CkXml_NewChild2(xml,"Exponent",exponent);

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

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

    usePrivateKey = FALSE;
    plainText = "message in a bottle";

    CkRsa_putEncodingMode(rsa,"base64");
    encryptedStrBase64 = CkRsa_encryptStringENC(rsa,plainText,usePrivateKey);
    printf("%s\n",encryptedStrBase64);


    CkRsa_Dispose(rsa);
    CkXml_Dispose(xml);
    CkPublicKey_Dispose(pubKey);

    }