(Unicode C++) RSA Encrypt and Decrypt Strings

See more RSA Examples

Note: This example requires Chilkat v11.0.0 or greater.

Chilkat C/C++ Library Downloads
MS Visual C/C++ C++ Builder Linux C/C++ Alpine Linux C/C++	MacOS C/C++ iOS C/C++ Android C/C++ MinGW C/C++

#include <CkRsaW.h>
#include <CkPrivateKeyW.h>
#include <CkPublicKeyW.h>

void ChilkatSample(void)
    {
    bool success = false;

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

    CkRsaW rsa;

    // This example also generates the public and private
    // keys to be used in the RSA encryption.
    // Normally, you would generate a key pair once,
    // and distribute the public key to your partner.
    // Anything encrypted with the public key can be
    // decrypted with the private key.  The reverse is 
    // also true: anything encrypted using the private
    // key can be decrypted using the public key.

    // Generate a 2048-bit key.  Chilkat RSA supports
    // key sizes ranging from 512 bits to 4096 bits.
    CkPrivateKeyW privKey;
    success = rsa.GenKey(2048,privKey);
    if (success == false) {
        wprintf(L"%s\n",rsa.lastErrorText());
        return;
    }

    CkPublicKeyW pubKey;
    privKey.ToPublicKey(pubKey);

    const wchar_t *plainText = L"Encrypting and decrypting should be easy!";

    // Start with a new RSA object to demonstrate that all we
    // need are the keys previously exported:
    CkRsaW rsaEncryptor;

    // Encrypted output is always binary.  In this case, we want
    // to encode the encrypted bytes in a printable string.
    // Our choices are "hex", "base64", "url", "quoted-printable".
    rsaEncryptor.put_EncodingMode(L"hex");

    // We'll encrypt with the public key and decrypt with the private
    // key.
    success = rsaEncryptor.UsePublicKey(pubKey);

    bool usePrivateKey = false;
    const wchar_t *encryptedStr = rsaEncryptor.encryptStringENC(plainText,usePrivateKey);
    wprintf(L"%s\n",encryptedStr);

    // Now decrypt:
    CkRsaW rsaDecryptor;

    rsaDecryptor.put_EncodingMode(L"hex");
    success = rsaDecryptor.UsePrivateKey(privKey);

    usePrivateKey = true;
    const wchar_t *decryptedStr = rsaDecryptor.decryptStringENC(encryptedStr,usePrivateKey);

    wprintf(L"%s\n",decryptedStr);
    }