(Lianja) Trust Specific Root CA Certificates

Demonstrates how to trust specific root CA certificates and none others.

Chilkat Lianja Extension Download Chilkat Lianja Extension

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

// This example will trust the Amazon root CA certificates provided at 
// https://www.amazontrust.com/repository/

// I've previously downloaded the root CA certificates to DER format.
// Add each to the Chilkat TrustedRoots singleton object.

loTRoots = createobject("CkTrustedRoots")

loCaCert = createobject("CkCert")
llSuccess = loCaCert.LoadFromFile("qa_data/certs/aws_root_ca/AmazonRootCA1.cer")
if (llSuccess = .F.) then
    ? loCaCert.LastErrorText
    release loTRoots
    release loCaCert
    return
endif

llSuccess = loTRoots.AddCert(loCaCert)

// Continue with the others.
// For brevity, we're not checking return values for success/failure.
llSuccess = loCaCert.LoadFromFile("qa_data/certs/aws_root_ca/AmazonRootCA2.cer")
llSuccess = loTRoots.AddCert(loCaCert)

llSuccess = loCaCert.LoadFromFile("qa_data/certs/aws_root_ca/AmazonRootCA3.cer")
llSuccess = loTRoots.AddCert(loCaCert)

llSuccess = loCaCert.LoadFromFile("qa_data/certs/aws_root_ca/AmazonRootCA4.cer")
llSuccess = loTRoots.AddCert(loCaCert)

llSuccess = loCaCert.LoadFromFile("qa_data/certs/aws_root_ca/SFSRootCAG2.cer")
llSuccess = loTRoots.AddCert(loCaCert)

// Indicate we don't want to automatically trust the operating system's installed root CA certificates.
// On a Windows operating system, this would be the registry-based CA certificate stores. 
// On a Linux system, this could be /etc/ssl/certs/ca-certificates.crt, if it exists.
loTRoots.TrustSystemCaRoots = .F.

// Activate the trusted roots object.
// Once activated, all Chilkat objects that use TLS connections (HTTP, REST, Socket, MailMan, IMAP, FTP, etc.)
// will fail the TLS handshake if the server certificate is not verified and rooted with one of our explicitly trusted root certificates.
llSuccess = loTRoots.Activate()

loHttp = createobject("CkHttp")

// Note: We also need to explicitly indicate that server certificates are to be verified.
loHttp.RequireSslCertVerify = .T.

// For example, the following should fail because www.chilkatsoft.com's server certificate is not rooted in one of the explicitly trusted root CA certs.
llSuccess = loHttp.Download("https://www.chilkatsoft.com/helloWorld.txt","qa_output/helloWorld.txt")
if (llSuccess <> .T.) then
    // The above Download should fail.
    ? loHttp.LastErrorText

    // There should be a message in the LastErrorText indicating that we were "Unable to build certificate chain to root.."
endif

// However, we should be able to make TLS connections to good.sca1a.amazontrust.com
llSuccess = loHttp.Download("https://good.sca1a.amazontrust.com/","qa_output/valid.html")
if (llSuccess <> .T.) then
    ? loHttp.LastErrorText
    release loTRoots
    release loCaCert
    release loHttp
    return
endif

// We can still examine the LastErrorText and we'll find this message within:  
// "The public key was successfully validated against the public key of the explicitly trusted root cert."
? loHttp.LastErrorText

? "Success!"


release loTRoots
release loCaCert
release loHttp