C
C
Examine SSL/TLS Server Certificate
See more Socket/SSL/TLS Examples
Demonstrates how an application can examine and check a server's SSL/TLS certificate.Chilkat C Downloads
#include <C_CkSocket.h>
#include <C_CkCert.h>
void ChilkatSample(void)
{
BOOL success;
HCkSocket socket;
BOOL useTls;
int maxWaitMs;
HCkCert cert;
success = FALSE;
// This example assumes the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.
socket = CkSocket_Create();
// Connect to a server.
useTls = TRUE;
maxWaitMs = 2000;
success = CkSocket_Connect(socket,"www.intel.com",443,useTls,maxWaitMs);
if (success == FALSE) {
printf("%s\n",CkSocket_lastErrorText(socket));
CkSocket_Dispose(socket);
return;
}
// If we get here, the TLS connection ws made..
// In any SSL/TLS handshake, the server sends its certificate in a TLS handshake message.
// Chilkat will keep it cached within the object that made the connection.
// Get the server's cert and examine a few things.
cert = CkCert_Create();
CkSocket_GetServerCert(socket,cert);
printf("Distinguished Name: %s\n",CkCert_subjectDN(cert));
printf("Common Name: %s\n",CkCert_subjectCN(cert));
printf("Issuer Distinguished Name: %s\n",CkCert_issuerDN(cert));
printf("Issuer Common Name: %s\n",CkCert_issuerCN(cert));
printf("Expired: %d\n",CkCert_getExpired(cert));
printf("Revoked: %d\n",CkCert_getRevoked(cert));
printf("Signature Verified: %d\n",CkCert_getSignatureVerified(cert));
printf("Trusted Root: %d\n",CkCert_getTrustedRoot(cert));
// Sample output:
// Distinguished Name: C=US, ST=California, O=Intel Corporation, CN=*.intel.com
// Common Name: *.intel.com
// Issuer Distinguished Name: C=GB, ST=Greater Manchester, L=Salford, O=Sectigo Limited, CN=Sectigo RSA Organization Validation Secure Server CA
// Issuer Common Name: Sectigo RSA Organization Validation Secure Server CA
// Expired: False
// Revoked: False
// Signature Verified: True
// Trusted Root: True
CkSocket_Dispose(socket);
CkCert_Dispose(cert);
}