android - HTTPS and self-signed certificate issue

Question

I have to use HTTPS for sending POST requests to a server (using a self-signed certificate). This is how I do it:

HttpClient httpClient = getHttpClient();

for (int i = 0; i < PARAMS.length && !mHttpPost.isAborted(); ++i) {
    mHttpPost.setURI(URI.create(mUri + "/" + PARAMS[i].getPath()));
    mHttpPost.setEntity(new UrlEncodedFormEntity(PARAMS[i].getContents(), HTTP.UTF_8));
    HttpResponse response = httpClient.execute(mHttpPost);
    [...]
}

With getHttpClient() defined as follows:

public static DefaultHttpClient getHttpClient() {

    DefaultHttpClient client = null;

    // Setting up parameters
    HttpParams params = new BasicHttpParams();
    HttpProtocolParams.setVersion(params, HttpVersion.HTTP_1_1);
    HttpProtocolParams.setContentCharset(params, "utf-8");
    params.setBooleanParameter("http.protocol.expect-continue", false);

    // Setting timeout
    HttpConnectionParams.setConnectionTimeout(params, TIMEOUT);
    HttpConnectionParams.setSoTimeout(params, TIMEOUT);

    // Registering schemes for both HTTP and HTTPS
    SchemeRegistry registry = new SchemeRegistry();
    registry.register(new Scheme("http", PlainSocketFactory.getSocketFactory(), 80));
    final SSLSocketFactory sslSocketFactory = SSLSocketFactory.getSocketFactory();
    sslSocketFactory.setHostnameVerifier(SSLSocketFactory.ALLOW_ALL_HOSTNAME_VERIFIER);
    registry.register(new Scheme("https", sslSocketFactory, 443));

    // Creating thread safe client connection manager
    ThreadSafeClientConnManager manager = new ThreadSafeClientConnManager(params, registry);

    // Creating HTTP client
    client = new DefaultHttpClient(manager, params);

    return client;

}

But I get a "Not trusted server certificate" exception. I know several questions about self-signed certificates have already been posted here, but none of them worked for me...

Does anyone know how to do?

Some details: I'm working with API level 4 (Android 1.6) on emulator.

Answer 1

I finally solved it, using a custom subclass of SSLSocketFactory:

public class CustomSSLSocketFactory extends SSLSocketFactory {

    private SSLContext sslContext = SSLContext.getInstance("TLS");

    public CustomSSLSocketFactory(KeyStore truststore) throws NoSuchAlgorithmException, KeyManagementException, KeyStoreException, UnrecoverableKeyException {

        super(truststore);

        TrustManager tm = new X509TrustManager() {

            public void checkClientTrusted(X509Certificate[] chain, String authType) throws certificateException {
        }

            public void checkServerTrusted(X509Certificate[] chain, String authType) throws CertificateException {
            }

            public X509Certificate[] getAcceptedIssuers() {
                return null;
            }

        };

        sslContext.init(null, new TrustManager[] {tm}, null);

    }

    @Override
    public Socket createSocket(Socket socket, String host, int port, boolean autoClose) throws IOException, UnknownHostException {
        return sslContext.getSocketFactory().createSocket(socket, host, port, autoClose);
    }

    @Override
    public Socket createSocket() throws IOException {
        return sslContext.getSocketFactory().createSocket();
    }

}

And I use it as follows:

public HttpClient getHttpClient() {

    DefaultHttpClient client = null;

    try {

        KeyStore trustStore = KeyStore.getInstance(KeyStore.getDefaultType());
        trustStore.load(null, null);

        SSLSocketFactory sf = new CustomSSLSocketFactory(trustStore);
        sf.setHostnameVerifier(SSLSocketFactory.ALLOW_ALL_HOSTNAME_VERIFIER);

        // Setting up parameters
        HttpParams params = new BasicHttpParams();
        HttpProtocolParams.setVersion(params, HttpVersion.HTTP_1_1);
        HttpProtocolParams.setContentCharset(params, "utf-8");
        params.setBooleanParameter("http.protocol.expect-continue", false);

        // Setting timeout
        HttpConnectionParams.setConnectionTimeout(params, TIMEOUT);
        HttpConnectionParams.setSoTimeout(params, TIMEOUT);

        // Registering schemes for both HTTP and HTTPS
        SchemeRegistry registry = new SchemeRegistry();
        registry.register(new Scheme("http", PlainSocketFactory.getSocketFactory(), 80));
        registry.register(new Scheme("https", sf, 443));

        // Creating thread safe client connection manager
        ClientConnectionManager ccm = new ThreadSafeClientConnManager(params, registry);

        // Creating HTTP client
        client = new DefaultHttpClient(ccm, params);

        // Registering user name and password for authentication
        client.getCredentialsProvider().setCredentials(
                new AuthScope(null, -1),
                new UsernamePasswordCredentials(mUsername, mPassword));

    } catch (Exception e) {
        client = new DefaultHttpClient();
    }

    return client;

}

Don't know why the other solutions I found did not work for me...