How to do an HTTPS POST from Android?

You can take a look at this question I asked a few days ago:

Change HTTP post request to HTTPS post request:

I have supplied there a solution that worked for me, that basically accepts any self-signed certificate. As been said here this solution is not recommended as it's not secure and open to a man-in-the-middle attacks.

Here is the code:

EasySSLSocketFactory:

public class EasySSLSocketFactory implements SocketFactory, LayeredSocketFactory {

private SSLContext sslcontext = null;

private static SSLContext createEasySSLContext() throws IOException {
    try {
        SSLContext context = SSLContext.getInstance("TLS");
        context.init(null, new TrustManager[] { new EasyX509TrustManager(null) }, null);
        return context;
    } catch (Exception e) {
        throw new IOException(e.getMessage());
    }
}

private SSLContext getSSLContext() throws IOException {
    if (this.sslcontext == null) {
        this.sslcontext = createEasySSLContext();
    }
    return this.sslcontext;
}

/**
 * @see org.apache.http.conn.scheme.SocketFactory#connectSocket(java.net.Socket, java.lang.String, int,
 *      java.net.InetAddress, int, org.apache.http.params.HttpParams)
 */
public Socket connectSocket(Socket sock, String host, int port, InetAddress localAddress, int localPort,
        HttpParams params) throws IOException, UnknownHostException, ConnectTimeoutException {
    int connTimeout = HttpConnectionParams.getConnectionTimeout(params);
    int soTimeout = HttpConnectionParams.getSoTimeout(params);
    InetSocketAddress remoteAddress = new InetSocketAddress(host, port);
    SSLSocket sslsock = (SSLSocket) ((sock != null) ? sock : createSocket());

    if ((localAddress != null) || (localPort > 0)) {
        // we need to bind explicitly
        if (localPort < 0) {
            localPort = 0; // indicates "any"
        }
        InetSocketAddress isa = new InetSocketAddress(localAddress, localPort);
        sslsock.bind(isa);
    }

    sslsock.connect(remoteAddress, connTimeout);
    sslsock.setSoTimeout(soTimeout);
    return sslsock;

}

/**
 * @see org.apache.http.conn.scheme.SocketFactory#createSocket()
 */
public Socket createSocket() throws IOException {
    return getSSLContext().getSocketFactory().createSocket();
}

/**
 * @see org.apache.http.conn.scheme.SocketFactory#isSecure(java.net.Socket)
 */
public boolean isSecure(Socket socket) throws IllegalArgumentException {
    return true;
}

/**
 * @see org.apache.http.conn.scheme.LayeredSocketFactory#createSocket(java.net.Socket, java.lang.String, int,
 *      boolean)
 */
public Socket createSocket(Socket socket, String host, int port, boolean autoClose) throws IOException,
        UnknownHostException {
    return getSSLContext().getSocketFactory().createSocket(socket, host, port, autoClose);
}

// -------------------------------------------------------------------
// javadoc in org.apache.http.conn.scheme.SocketFactory says :
// Both Object.equals() and Object.hashCode() must be overridden
// for the correct operation of some connection managers
// -------------------------------------------------------------------

public boolean equals(Object obj) {
    return ((obj != null) && obj.getClass().equals(EasySSLSocketFactory.class));
}

public int hashCode() {
    return EasySSLSocketFactory.class.hashCode();
}
}

EasyX509TrustManager:

public class EasyX509TrustManager implements X509TrustManager {

private X509TrustManager standardTrustManager = null;

/**
 * Constructor for EasyX509TrustManager.
 */
public EasyX509TrustManager(KeyStore keystore) throws NoSuchAlgorithmException, KeyStoreException {
    super();
    TrustManagerFactory factory = TrustManagerFactory.getInstance(TrustManagerFactory.getDefaultAlgorithm());
    factory.init(keystore);
    TrustManager[] trustmanagers = factory.getTrustManagers();
    if (trustmanagers.length == 0) {
        throw new NoSuchAlgorithmException("no trust manager found");
    }
    this.standardTrustManager = (X509TrustManager) trustmanagers[0];
}

/**
 * @see javax.net.ssl.X509TrustManager#checkClientTrusted(X509Certificate[],String authType)
 */
public void checkClientTrusted(X509Certificate[] certificates, String authType) throws CertificateException {
    standardTrustManager.checkClientTrusted(certificates, authType);
}

/**
 * @see javax.net.ssl.X509TrustManager#checkServerTrusted(X509Certificate[],String authType)
 */
public void checkServerTrusted(X509Certificate[] certificates, String authType) throws CertificateException {
    if ((certificates != null) && (certificates.length == 1)) {
        certificates[0].checkValidity();
    } else {
        standardTrustManager.checkServerTrusted(certificates, authType);
    }
}

/**
 * @see javax.net.ssl.X509TrustManager#getAcceptedIssuers()
 */
public X509Certificate[] getAcceptedIssuers() {
    return this.standardTrustManager.getAcceptedIssuers();
}
}

And I added this method: getNewHttpClient()

public static HttpClient getNewHttpClient() {
    try {
        KeyStore trustStore = KeyStore.getInstance(KeyStore.getDefaultType());
        trustStore.load(null, null);

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

        HttpParams params = new BasicHttpParams();
        HttpProtocolParams.setVersion(params, HttpVersion.HTTP_1_1);
        HttpProtocolParams.setContentCharset(params, HTTP.UTF_8);

        SchemeRegistry registry = new SchemeRegistry();
        registry.register(new Scheme("http", PlainSocketFactory.getSocketFactory(), 80));
        registry.register(new Scheme("https", sf, 443));

        ClientConnectionManager ccm = new ThreadSafeClientConnManager(params, registry);

        return new DefaultHttpClient(ccm, params);
    } catch (Exception e) {
        return new DefaultHttpClient();
    }
}

Finally for every place in my code that I had:

DefaultHttpClient client = new DefaultHttpClient();

I replace it with:

HttpClient client = getNewHttpClient();

You can use the default CAs that are defined in the android device, which is just fine for any public web.

If you have a self-signed certificate, you can either accept all certificates (risky, open to man-in-the-middle attacks) or create your own TrustManagerFactory, which is a bit out of this scope.

Here's some code to use the default CAs for a https POST call:

private InputStream getInputStream(String urlStr, String user, String password) throws IOException
{
    URL url = new URL(urlStr);
    HttpsURLConnection conn = (HttpsURLConnection) url.openConnection();

    // Create the SSL connection
    SSLContext sc;
    sc = SSLContext.getInstance("TLS");
    sc.init(null, null, new java.security.SecureRandom());
    conn.setSSLSocketFactory(sc.getSocketFactory());
      
    // Use this if you need SSL authentication
    String userpass = user + ":" + password;
    String basicAuth = "Basic " + Base64.encodeToString(userpass.getBytes(), Base64.DEFAULT);
    conn.setRequestProperty("Authorization", basicAuth);
    
    // set Timeout and method
    conn.setReadTimeout(7000);
    conn.setConnectTimeout(7000);
    conn.setRequestMethod("POST");
    conn.setDoInput(true);
    
    // Add any data you wish to post here
    
    conn.connect();
    return conn.getInputStream();
}   

To read the response:

String result = new String();
InputStream is = getInputStream(urlStr, user, password);
BufferedReader in = new BufferedReader(new InputStreamReader(is));
String inputLine;
while ((inputLine = in.readLine()) != null) {
    result += inputLine;            
}       

Here's an Android HttpsUrlConnection POST solution complete with certificate pinning, timeouts server side code and configurations.

The variable params should be in the form username=demo&password=abc123&.

@Override
public String sendHttpRequest(String params) {
    String result = "";
    try {
        URL url = new URL(AUTHENTICATION_SERVER_ADDRESS);
        HttpsURLConnection connection = (HttpsURLConnection) url.openConnection();
        connection.setSSLSocketFactory(KeyPinStore.getInstance().getContext().getSocketFactory()); // Tell the URLConnection to use a SocketFactory from our SSLContext
        connection.setRequestMethod("POST");
        connection.setDoOutput(true);
        connection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
        connection.setConnectTimeout(10000);
        connection.setReadTimeout(10000);
        PrintWriter out = new PrintWriter(connection.getOutputStream());
        out.println(params);
        out.close();
        BufferedReader in = new BufferedReader(new InputStreamReader(connection.getInputStream()), 8192);
        String inputLine;
        while ((inputLine = in.readLine()) != null) {
            result = result.concat(inputLine);
        }
        in.close();
        //} catch (IOException e) {
    } catch (IOException | KeyStoreException | CertificateException | KeyManagementException | NoSuchAlgorithmException e) {
        result = e.toString();
        e.printStackTrace();
    }
    return result;
}