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Unicode C

Verify SSL Server Certificate

See more Socket/SSL/TLS Examples

Demonstrates how to connect to an SSL server and verify its SSL certificate.

Chilkat Unicode C Downloads

Unicode C
#include <C_CkSocketW.h>
#include <C_CkCertW.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkSocketW socket;
    BOOL ssl;
    int maxWaitMillisec;
    const wchar_t *sslServerHost;
    int sslServerPort;
    HCkCertW cert;
    BOOL bExpired;
    BOOL bRevoked;
    BOOL bSignatureVerified;
    BOOL bTrustedRoot;

    success = FALSE;

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

    socket = CkSocketW_Create();

    ssl = TRUE;
    maxWaitMillisec = 20000;

    // The SSL server hostname may be an IP address, a domain name,
    // or "localhost". 

    sslServerHost = L"www.paypal.com";
    sslServerPort = 443;

    // Connect to the SSL server:
    success = CkSocketW_Connect(socket,sslServerHost,sslServerPort,ssl,maxWaitMillisec);
    if (success == FALSE) {
        wprintf(L"%s\n",CkSocketW_lastErrorText(socket));
        CkSocketW_Dispose(socket);
        return;
    }

    cert = CkCertW_Create();

    success = CkSocketW_GetServerCert(socket,cert);
    if (success != FALSE) {

        wprintf(L"Server Certificate:\n");
        wprintf(L"Distinguished Name: %s\n",CkCertW_subjectDN(cert));
        wprintf(L"Common Name: %s\n",CkCertW_subjectCN(cert));
        wprintf(L"Issuer Distinguished Name: %s\n",CkCertW_issuerDN(cert));
        wprintf(L"Issuer Common Name: %s\n",CkCertW_issuerCN(cert));

        bExpired = CkCertW_getExpired(cert);
        bRevoked = CkCertW_getRevoked(cert);
        bSignatureVerified = CkCertW_getSignatureVerified(cert);
        bTrustedRoot = CkCertW_getTrustedRoot(cert);

        wprintf(L"Expired: %d\n",bExpired);
        wprintf(L"Revoked: %d\n",bRevoked);
        wprintf(L"Signature Verified: %d\n",bSignatureVerified);
        wprintf(L"Trusted Root: %d\n",bTrustedRoot);

    }

    // Close the connection with the server
    // Wait a max of 20 seconds (20000 millsec)
    success = CkSocketW_Close(socket,20000);


    CkSocketW_Dispose(socket);
    CkCertW_Dispose(cert);

    }