java - PKIX path building failed while making SSL connection

Question

I'm integrating with a Merchant Account called CommWeb and I'm sending an SSL post to their URL (https://migs.mastercard.com.au/vpcdps). When I try to send the post, I get the following exception:

sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target

The code (which I didn't write, and that already exists in our codebase) that performs the post is:

public static HttpResponse sendHttpPostSSL(String url, Map<String, String> params) throws IOException {
    PostMethod postMethod = new PostMethod(url);
    for (Map.Entry<String, String> entry : params.entrySet()) {
        postMethod.addParameter(entry.getKey(), StringUtils.Nz(entry.getValue()));
    }

    HttpClient client = new HttpClient();
    int status = client.executeMethod(postMethod);
    if (status == 200) {
        StringBuilder resultBuffer = new StringBuilder();
        resultBuffer.append(postMethod.getResponseBodyAsString());
        return new HttpResponse(resultBuffer.toString(), "");
    } else {
        throw new IOException("Invalid response code: " + status);
    }
}

The documentation for the Merchant Account integration says nothing about certificates. They did provide some sample JSP code that seems to blindly accept certificates:

<%! // Define Static Constants
    // ***********************
public static X509TrustManager s_x509TrustManager = null;
public static SSLSocketFactory s_sslSocketFactory = null;

static {
        s_x509TrustManager = new X509TrustManager() {
        public X509Certificate[] getAcceptedIssuers() { return new X509Certificate[] {}; } 
        public boolean isClientTrusted(X509Certificate[] chain) { return true; } 
        public boolean isServerTrusted(X509Certificate[] chain) { return true; } 
    };

    java.security.Security.addProvider(new com.sun.net.ssl.internal.ssl.Provider());
    try {
        SSLContext context = SSLContext.getInstance("TLS");
        context.init(null, new X509TrustManager[] { s_x509TrustManager }, null);
        s_sslSocketFactory = context.getSocketFactory();
    } catch (Exception e) {
        e.printStackTrace();
        throw new RuntimeException(e.getMessage());
    }
}

...
...
           // write output to VPC
            SSLSocket ssl = (SSLSocket)s_sslSocketFactory.createSocket(s, vpc_Host, vpc_Port, true);
            ssl.startHandshake();
            os = ssl.getOutputStream();
            // get response data from VPC
            is = ssl.getInputStream();
...
...
%>

Our webapp has a keystore, and I tried adding the certificate (which I exported from firefox) using the keytool command, but that didn't work and I got the same error. I've tried solutions on the web (importing the key and using System.setProperty) but that seems kind of clunky and it didn't work (gave me a NoSuchAlgorithmError). Any help is appreciated!

Answer 1

Evidently the valicert class 3 CA certificate is not in your default truststore (which is probably the cacerts file in your JRE lib/security directory, but see the JSSE documentation for the full story).

You could add this certificate to the cacerts file, but I don't recommend this. Instead, I think you should create your own truststore file (which can be a copy of the cacerts file) and add the valicert root ca to this. Then point to this file with the javax.net.ssl.trustStore system property.