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Unicode C

Generate an RSA Key and Get as Base64 DER

See more RSA Examples

Demonstrates how to generate a 2048-bit RSA key and return the public and private parts as unencrypted Base64 encoded DER.

Chilkat Unicode C Downloads

Unicode C
#include <C_CkRsaW.h>
#include <C_CkPrivateKeyW.h>
#include <C_CkPublicKeyW.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkRsaW rsa;
    HCkPrivateKeyW privKey;
    HCkPublicKeyW pubKey;
    BOOL bChoosePkcs1;
    const wchar_t *pubKeyBase64Der;
    const wchar_t *privKeyPkcs1;
    const wchar_t *privKeyPkcs8;

    success = FALSE;

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

    rsa = CkRsaW_Create();

    // Generate a 2048-bit key.
    privKey = CkPrivateKeyW_Create();
    success = CkRsaW_GenKey(rsa,2048,privKey);
    if (success == FALSE) {
        wprintf(L"%s\n",CkRsaW_lastErrorText(rsa));
        CkRsaW_Dispose(rsa);
        CkPrivateKeyW_Dispose(privKey);
        return;
    }

    // Get the public part of the key.
    pubKey = CkPublicKeyW_Create();
    CkPrivateKeyW_ToPublicKey(privKey,pubKey);

    // There are two possible formats for representing the RSA public key 
    // in ASN.1 (DER).  The possible formats are PKCS1 and PKCS8.
    // We can get either by setting bChoosePkcs1 to TRUE or FALSE.
    bChoosePkcs1 = TRUE;
    pubKeyBase64Der = CkPublicKeyW_getEncoded(pubKey,bChoosePkcs1,L"base64");
    wprintf(L"Public Key Base64 DER:\n");
    wprintf(L"%s\n",pubKeyBase64Der);

    // Get the private key as Base64 DER:
    // We can get PKCS1 or PKCS8, but with different methods:
    privKeyPkcs1 = CkPrivateKeyW_getPkcs1ENC(privKey,L"base64");
    wprintf(L"Private Key PKCS1 Base64 DER:\n");
    wprintf(L"%s\n",privKeyPkcs1);

    privKeyPkcs8 = CkPrivateKeyW_getPkcs8ENC(privKey,L"base64");
    wprintf(L"Private Key PKCS8 Base64 DER:\n");
    wprintf(L"%s\n",privKeyPkcs8);


    CkRsaW_Dispose(rsa);
    CkPrivateKeyW_Dispose(privKey);
    CkPublicKeyW_Dispose(pubKey);

    }