TrustManagerFactory.java

package com.ushahidi.android.app.net;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.security.KeyStore;
import java.security.KeyStoreException;
import java.security.NoSuchAlgorithmException;
import java.security.cert.CertificateException;
import java.security.cert.X509Certificate;
import java.util.HashMap;
import java.util.Map;

import javax.net.ssl.TrustManager;
import javax.net.ssl.X509TrustManager;

import android.app.Application;
import android.content.Context;
import android.util.Log;

import com.ushahidi.android.app.MainApplication;

public final class TrustManagerFactory {
    private static final String LOG_TAG = "TrustManagerFactory";

    private static X509TrustManager defaultTrustManager;

    private static X509TrustManager unsecureTrustManager;

    private static X509TrustManager localTrustManager;

    private static X509Certificate[] lastCertChain = null;

    private static File keyStoreFile;

    private static KeyStore keyStore;

    private static class SimpleX509TrustManager implements X509TrustManager {
        public void checkClientTrusted(X509Certificate[] chain, String authType)
                throws CertificateException {
        }

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

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

    private static class SecureX509TrustManager implements X509TrustManager {
        private static final Map<String, SecureX509TrustManager> mTrustManager = new HashMap<String, SecureX509TrustManager>();

        private final String mHost;

        private SecureX509TrustManager(String host) {
            mHost = host;
        }

        public synchronized static X509TrustManager getInstance(String host) {
            SecureX509TrustManager trustManager;
            if (mTrustManager.containsKey(host)) {
                trustManager = mTrustManager.get(host);
            } else {
                trustManager = new SecureX509TrustManager(host);
                mTrustManager.put(host, trustManager);
            }

            return trustManager;
        }

        public void checkClientTrusted(X509Certificate[] chain, String authType)
                throws CertificateException {
            defaultTrustManager.checkClientTrusted(chain, authType);
        }

        public void checkServerTrusted(X509Certificate[] chain, String authType)
                throws CertificateException {
            // FIXME: Using a static field to store the certificate chain is a
            // bad idea. Instead
            // create a CertificateException subclass and store the chain there.
            TrustManagerFactory.setLastCertChain(chain);
            try {
                defaultTrustManager.checkServerTrusted(chain, authType);
            } catch (CertificateException e) {
                localTrustManager.checkServerTrusted(new X509Certificate[] {
                    chain[0]
                }, authType);
            }

            try {
                String dn = chain[0].getSubjectDN().toString();
                if ((dn != null) && (dn.equalsIgnoreCase(keyStore.getCertificateAlias(chain[0])))) {
                    return;
                }
            } catch (KeyStoreException e) {
                throw new CertificateException(
                        "Certificate cannot be verified; KeyStore Exception: " + e);
            }
            throw new CertificateException("Certificate domain name does not match " + mHost);
        }

        public X509Certificate[] getAcceptedIssuers() {
            return defaultTrustManager.getAcceptedIssuers();
        }

    }

    static {
        java.io.InputStream fis = null;
        try {
            javax.net.ssl.TrustManagerFactory tmf = javax.net.ssl.TrustManagerFactory
                    .getInstance("X509");
            Application app = MainApplication.app;
            keyStoreFile = new File(app.getDir("KeyStore", Context.MODE_PRIVATE) + File.separator
                    + "KeyStore.bks");
            keyStore = KeyStore.getInstance(KeyStore.getDefaultType());
            try {
                fis = new java.io.FileInputStream(keyStoreFile);
            } catch (FileNotFoundException e1) {
                fis = null;
            }
            try {
                keyStore.load(fis, "".toCharArray());
            } catch (IOException e) {
                Log.e(LOG_TAG, "KeyStore IOException while initializing TrustManagerFactory ", e);
                keyStore = null;
            } catch (CertificateException e) {
                Log.e(LOG_TAG,
                        "KeyStore CertificateException while initializing TrustManagerFactory ", e);
                keyStore = null;
            }
            Log.i(LOG_TAG,"keyStore: "+keyStore.toString());
            tmf.init(keyStore);
            TrustManager[] tms = tmf.getTrustManagers();
            if (tms != null) {
                for (TrustManager tm : tms) {
                    if (tm instanceof X509TrustManager) {
                        localTrustManager = (X509TrustManager)tm;
                        break;
                    }
                }
            }
            tmf = javax.net.ssl.TrustManagerFactory.getInstance("X509");
            tmf.init((KeyStore)null);
            tms = tmf.getTrustManagers();
            if (tms != null) {
                for (TrustManager tm : tms) {
                    if (tm instanceof X509TrustManager) {
                        defaultTrustManager = (X509TrustManager)tm;
                        break;
                    }
                }
            }

        } catch (NoSuchAlgorithmException e) {
            Log.e(LOG_TAG, "Unable to get X509 Trust Manager ", e);
        } catch (KeyStoreException e) {
            Log.e(LOG_TAG, "Key Store exception while initializing TrustManagerFactory ", e);
        } finally {
            
        }
        unsecureTrustManager = new SimpleX509TrustManager();
    }

    private TrustManagerFactory() {
    }

    public static X509TrustManager get(String host, boolean secure) {
        return secure ? SecureX509TrustManager.getInstance(host) : unsecureTrustManager;
    }

    public static KeyStore getKeyStore() {
        return keyStore;
    }

    public static void setLastCertChain(X509Certificate[] chain) {
        lastCertChain = chain;
    }

    public static X509Certificate[] getLastCertChain() {
        return lastCertChain;
    }

    public static void addCertificateChain(String alias, X509Certificate[] chain)
            throws CertificateException {
        try {
            javax.net.ssl.TrustManagerFactory tmf = javax.net.ssl.TrustManagerFactory
                    .getInstance("X509");
            for (X509Certificate element : chain) {
                keyStore.setCertificateEntry(element.getSubjectDN().toString(), element);
            }

            tmf.init(keyStore);
            TrustManager[] tms = tmf.getTrustManagers();
            if (tms != null) {
                for (TrustManager tm : tms) {
                    if (tm instanceof X509TrustManager) {
                        localTrustManager = (X509TrustManager)tm;
                        break;
                    }
                }
            }
            java.io.OutputStream keyStoreStream = null;
            try {
                keyStoreStream = new java.io.FileOutputStream(keyStoreFile);
                keyStore.store(keyStoreStream, "".toCharArray());
            } catch (FileNotFoundException e) {
                throw new CertificateException("Unable to write KeyStore: " + e.getMessage());
            } catch (CertificateException e) {
                throw new CertificateException("Unable to write KeyStore: " + e.getMessage());
            } catch (IOException e) {
                throw new CertificateException("Unable to write KeyStore: " + e.getMessage());
            } finally {
                
            }

        } catch (NoSuchAlgorithmException e) {
            Log.e(LOG_TAG, "Unable to get X509 Trust Manager ", e);
        } catch (KeyStoreException e) {
            Log.e(LOG_TAG, "Key Store exception while initializing TrustManagerFactory ", e);
        }
    }
}