Set the Decryption Certificate and Private Key

See more Email Object Examples

Demonstrates the Chilkat Email.SetDecryptCert2 method, which explicitly provides a certificate and its corresponding private key as separate objects for decrypting a received encrypted email. Set them before loading the encrypted message. This example loads a .cer certificate and a PEM private key, sets both, then loads an encrypted email.

Background: Sometimes the certificate and its private key are stored separately — a public .cer file plus a PEM (or other format) key file — rather than combined in a PFX. SetDecryptCert2 accepts the two objects individually, which is the natural fit for that arrangement. It is the two-object counterpart to SetDecryptCert, which takes a single certificate that already carries its private key.

Chilkat C Downloads

Download Chilkat for C

#include <C_CkEmail.h>
#include <C_CkCert.h>
#include <C_CkPrivateKey.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkEmail email;
    HCkCert cert;
    HCkPrivateKey privKey;

    success = FALSE;

    //  Demonstrates the SetDecryptCert2 method, which explicitly provides a certificate and its
    //  corresponding private key (as separate objects) for decrypting a received encrypted
    //  email.  Set them before loading the encrypted email.

    email = CkEmail_Create();

    //  Load the certificate (public) and the matching private key from separate files.
    cert = CkCert_Create();
    success = CkCert_LoadFromFile(cert,"qa_data/certs/recipient.cer");
    if (success == FALSE) {
        printf("%s\n",CkCert_lastErrorText(cert));
        CkEmail_Dispose(email);
        CkCert_Dispose(cert);
        return;
    }

    privKey = CkPrivateKey_Create();
    success = CkPrivateKey_LoadPemFile(privKey,"qa_data/certs/recipient_privkey.pem");
    if (success == FALSE) {
        printf("%s\n",CkPrivateKey_lastErrorText(privKey));
        CkEmail_Dispose(email);
        CkCert_Dispose(cert);
        CkPrivateKey_Dispose(privKey);
        return;
    }

    //  Provide the certificate and private key to use for decryption.
    success = CkEmail_SetDecryptCert2(email,cert,privKey);
    if (success == FALSE) {
        printf("%s\n",CkEmail_lastErrorText(email));
        CkEmail_Dispose(email);
        CkCert_Dispose(cert);
        CkPrivateKey_Dispose(privKey);
        return;
    }

    //  Load the encrypted email; Chilkat decrypts it using the certificate and key.
    success = CkEmail_LoadEml(email,"qa_data/eml/encrypted.eml");
    if (success == FALSE) {
        printf("%s\n",CkEmail_lastErrorText(email));
        CkEmail_Dispose(email);
        CkCert_Dispose(cert);
        CkPrivateKey_Dispose(privKey);
        return;
    }

    printf("Decrypted = %d\n",CkEmail_getDecrypted(email));

    //  Note: Paths such as "qa_data/..." are relative local filesystem paths,
    //  relative to the current working directory of the running application.


    CkEmail_Dispose(email);
    CkCert_Dispose(cert);
    CkPrivateKey_Dispose(privKey);

    }