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C

PKCS11 Find Certificate with Key Usage on Smart Card or USB Token

See more PKCS11 Examples

Demonstrates how to find and return the 1st certificate on a smart card or USB token with a desired intended key usage.

Note: This example requires Chilkat v9.5.0.91 or later.

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C
#include <C_CkPkcs11.h>
#include <C_CkCert.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkPkcs11 pkcs11;
    int slotID;
    BOOL readWrite;
    int userType;
    const char *pin;
    HCkCert cert;

    success = FALSE;

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

    // Note: Chilkat's PKCS11 implementation runs on Windows, Linux, Mac OS X, and other supported operating systems.

    pkcs11 = CkPkcs11_Create();

    CkPkcs11_putSharedLibPath(pkcs11,"aetpkss1.dll");

    success = CkPkcs11_Initialize(pkcs11);
    if (success == FALSE) {
        printf("%s\n",CkPkcs11_lastErrorText(pkcs11));
        CkPkcs11_Dispose(pkcs11);
        return;
    }

    // Pass -1 for the slotID to open a session on the first non-empty slot.
    slotID = -1;

    // Open a session.
    readWrite = TRUE;
    success = CkPkcs11_OpenSession(pkcs11,slotID,readWrite);
    if (success == FALSE) {
        printf("%s\n",CkPkcs11_lastErrorText(pkcs11));
        CkPkcs11_Dispose(pkcs11);
        return;
    }

    // Make it an authenticated session by calling Login.
    // 
    // If we don't authenticate, then we won't be able to see the private keys, and thus
    // we won't know which certificates have an associated private key stored on the smart card.

    // The smart card PIN is passed to the Login method.
    // userType 1 indicates a "Normal User".
    userType = 1;
    pin = "0000";
    success = CkPkcs11_Login(pkcs11,userType,pin);
    if (success == FALSE) {
        printf("%s\n",CkPkcs11_lastErrorText(pkcs11));
        success = CkPkcs11_CloseSession(pkcs11);
        CkPkcs11_Dispose(pkcs11);
        return;
    }

    // --------------------------------------------------------------------------

    cert = CkCert_Create();

    // Find a certificate with an intended key usage.
    // Possible key usages to find are:
    // 
    // DigitalSignature
    // NonRepudiation
    // KeyEncipherment
    // DataEncipherment
    // CertificateSigning
    // CrlSigning
    // 
    // To find a cert having any one of several usages, pass a comma-separated list of usages:
    success = CkPkcs11_FindCert(pkcs11,"keyUsage","NonRepudiation,DigitalSignature",cert);
    if (success == TRUE) {
        printf("Cert with private key: %s\n",CkCert_subjectCN(cert));
    }
    else {
        printf("No certificates having the intended key usage were found.\n");
    }

    // --------------------------------------------------------------------------

    // Revert to an unauthenticated session by calling Logout.
    success = CkPkcs11_Logout(pkcs11);
    if (success == FALSE) {
        printf("%s\n",CkPkcs11_lastErrorText(pkcs11));
        success = CkPkcs11_CloseSession(pkcs11);
        CkPkcs11_Dispose(pkcs11);
        CkCert_Dispose(cert);
        return;
    }

    // When finished, close the session.
    // It is important to close the session (memory leaks will occur if the session is not properly closed).
    success = CkPkcs11_CloseSession(pkcs11);
    if (success == FALSE) {
        printf("%s\n",CkPkcs11_lastErrorText(pkcs11));
        CkPkcs11_Dispose(pkcs11);
        CkCert_Dispose(cert);
        return;
    }

    printf("Success.\n");


    CkPkcs11_Dispose(pkcs11);
    CkCert_Dispose(cert);

    }