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Android SSL HTTP Request using self signed cert and CA

I have an android application that is connecting to an SSL web service that we host. The Web server is apache and has its own CA that we created and a self signed SSL certificate.

I have imported our CA certificate onto the Android tablet in the User Trusted certificates section in Security.

I have tested access to the web server and can confirm that the web service certificate shows as valid (screenshot below)

Valid certificate

Here is the certificate in the security settings:

Trusted certificate

Now when I try and access the webservice in my application I get the "No Peer Certificate" exception being triggered.

This is the SSL implementation simplified:

public class MainActivity extends Activity {

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    // allows network on main thread (temp hack)
    StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build(); 
    StrictMode.setThreadPolicy(policy);

    SchemeRegistry schemeRegistry = new SchemeRegistry();
    //schemeRegistry.register(new Scheme("https", SSLSocketFactory.getSocketFactory(), 443));
    schemeRegistry.register(new Scheme("https", newSSLSocketFactory(), 443));


    HttpParams params = new BasicHttpParams();

    SingleClientConnManager mgr = new SingleClientConnManager(params, schemeRegistry);

    HttpClient client = new DefaultHttpClient(mgr, params);

    HttpPost httpRequest = new HttpPost("https://our-web-service.com");

    try {
        client.execute(httpRequest);
    } catch (Exception e) {
        e.printStackTrace(); //
    }
}

/* 
 * Standard SSL CA Store Setup //
 */
private SSLSocketFactory newSSLSocketFactory() {

    KeyStore trusted;

    try {
        trusted = KeyStore.getInstance("AndroidCAStore");
        trusted.load(null, null);
        Enumeration<String> aliases = trusted.aliases();

        while (aliases.hasMoreElements()) {
            String alias = aliases.nextElement();
            X509Certificate cert = (X509Certificate) trusted.getCertificate(alias);
            Log.d("", "Alias="+alias);
            Log.d("", "Subject DN: " + cert.getSubjectDN().getName());
            Log.d("", "Issuer DN: " + cert.getIssuerDN().getName());
        }      

        SSLSocketFactory sf = new SSLSocketFactory(trusted);
        sf.setHostnameVerifier(SSLSocketFactory.STRICT_HOSTNAME_VERIFIER);

        return sf;

    } catch (Exception e) {
        // TODO Auto-generated catch block
        throw new AssertionError(e);
    }  
}

}

The while loop just spits out the certificates and I can see my own CA in the logs. But I still get the "No Peer Certificate" exception.

10-17 18:29:01.234: I/System.out(4006): No peer certificate

Do I have to manually load my CA certificate somehow in this implementation?

like image 301
Andy Davies Avatar asked Oct 17 '13 17:10

Andy Davies


People also ask

How can I take self-signed certificate in Android?

Go to Settings / Security / Credential storage and select “Install from device storage”. The . crt file will be detected and you will be prompted to enter a certificate name. After importing the certificate, you will find it in Settings / Security / Credential storage / Trusted credentials / User.


2 Answers

Solved by using: HttpsURLConnection

URLConnection conn = null;
URL url = new URL(strURL);
conn = url.openConnection();
HttpsURLConnection httpsConn = (HttpsURLConnection) conn;

This seems to work fine with user installed CA certificates.

like image 50
Andy Davies Avatar answered Oct 12 '22 12:10

Andy Davies


You can accomplished the task also using DefaultHttpClient, even though here is suggested to:

Prefer HttpURLConnection for new code

Pay attention also in importing or adding certificate to your application since you may have problems in updating the certificate when it will expire.

Here how to get a DefaultHttpClient trusting a self-signed certificate:

 * This method returns the appropriate HttpClient.
 * @param isTLS Whether Transport Layer Security is required.
 * @param trustStoreInputStream The InputStream generated from the BKS keystore.
 * @param trustStorePsw The password related to the keystore.
 * @return The DefaultHttpClient object used to invoke execute(request) method.
private DefaultHttpClient getHttpClient(boolean isTLS, InputStream trustStoreInputStream, String trustStorePsw) 
    throws KeyStoreException, NoSuchAlgorithmException, CertificateException, IOException, KeyManagementException, UnrecoverableKeyException {
    DefaultHttpClient client = null;        
    SchemeRegistry schemeRegistry = new SchemeRegistry();
    Scheme http = new Scheme("http", PlainSocketFactory.getSocketFactory(), 8080);
    schemeRegistry.register(http);
    if(isTLS) {
        KeyStore trustKeyStore = null;
        char[] trustStorePswCharArray = null;
        if(trustStorePsw!=null) {
            trustStorePswCharArray = trustStorePsw.toCharArray();
        } 
        trustKeyStore = KeyStore.getInstance("BKS");
        trustKeyStore.load(trustStoreInputStream, trustStorePswCharArray);
        SSLSocketFactory sslSocketFactory = null;
        sslSocketFactory = new SSLSocketFactory(trustKeyStore);
        Scheme https = new Scheme("https", sslSocketFactory, 8443);
        schemeRegistry.register(https);
    }                
    HttpParams httpParams = new BasicHttpParams();
    HttpConnectionParams.setConnectionTimeout(httpParams, CONNECTION_TIMEOUT);
    HttpConnectionParams.setSoTimeout(httpParams, SOCKET_TIMEOUT);        
    ClientConnectionManager clientConnectionManager = new ThreadSafeClientConnManager(httpParams, schemeRegistry);        
    client = new DefaultHttpClient(clientConnectionManager, httpParams);        
    return client;
}

and here how to get a HttpsURLConnection:

 * This method set the certificate for the HttpsURLConnection
 * @param url The url to contact.
 * @param certificateInputStream The InputStream generated from the .crt certificate.
 * @param certAlias The alias for the certificate. 
 * @return The returned HttpsURLConnection
private HttpsURLConnection getHttpsURLConnection(URL url, InputStream certificateInputStream, String certAlias) 
    throws CertificateException, IOException, KeyStoreException, NoSuchAlgorithmException, KeyManagementException {
    HttpsURLConnection connection = null;
    CertificateFactory certFactory = null;
    Certificate cert = null;
    KeyStore keyStore = null;
    TrustManagerFactory tmFactory = null;
    SSLContext sslContext = null;
    // Load certificates from an InputStream
    certFactory = CertificateFactory.getInstance("X.509");
    cert = certFactory.generateCertificate(certificateInputStream);
    certificateInputStream.close();
    // Create a KeyStore containing the trusted certificates
    keyStore = KeyStore.getInstance(KeyStore.getDefaultType());
    keyStore.load(null, null);
    keyStore.setCertificateEntry(certAlias, cert);
    // Create a TrustManager that trusts the certificates in our KeyStore
    tmFactory = TrustManagerFactory.getInstance(TrustManagerFactory.getDefaultAlgorithm());
    tmFactory.init(keyStore);
    // Create an SSLContext that uses our TrustManager
    sslContext = SSLContext.getInstance("TLS");
    sslContext.init(null, tmFactory.getTrustManagers(), null);
    connection = (HttpsURLConnection)url.openConnection();
    connection.setSSLSocketFactory(sslContext.getSocketFactory());
    return connection;
}
like image 40
bardi Avatar answered Oct 12 '22 10:10

bardi