root/chrome/android/java/src/org/chromium/chrome/browser/CertificateViewer.java

DEFINITIONS

1. showCertificateChain
2. showCertificateChain
3. showDialogForView
4. addCertificate
5. addCertificateDetails
6. addSectionTitle
7. addItem
8. addLabel
9. addValue
10. formatBytes
11. getDigest
12. onItemSelected
13. onNothingSelected
14. nativeGetCertIssuedToText
15. nativeGetCertInfoCommonNameText
16. nativeGetCertInfoOrganizationText
17. nativeGetCertInfoSerialNumberText
18. nativeGetCertInfoOrganizationUnitText
19. nativeGetCertIssuedByText
20. nativeGetCertValidityText
21. nativeGetCertIssuedOnText
22. nativeGetCertExpiresOnText
23. nativeGetCertFingerprintsText
24. nativeGetCertSHA256FingerprintText
25. nativeGetCertSHA1FingerprintText

// Copyright 2013 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

package org.chromium.chrome.browser;

import android.app.Dialog;
import android.content.Context;
import android.graphics.Typeface;
import android.net.http.SslCertificate;
import android.text.format.DateFormat;
import android.util.Log;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemSelectedListener;
import android.widget.ArrayAdapter;
import android.widget.LinearLayout;
import android.widget.ScrollView;
import android.widget.Spinner;
import android.widget.TextView;

import org.chromium.chrome.R;

import java.io.ByteArrayInputStream;
import java.security.MessageDigest;
import java.security.cert.Certificate;
import java.security.cert.CertificateException;
import java.security.cert.CertificateFactory;
import java.security.cert.X509Certificate;
import java.util.ArrayList;

/**
 * UI component for displaying certificate information.
 */
class CertificateViewer implements OnItemSelectedListener {
    private static final String X_509 = "X.509";
    private final Context mContext;
    private final ArrayList<LinearLayout> mViews;
    private final ArrayList<String> mTitles;
    private final int mPadding;
    private CertificateFactory mCertificateFactory;

    /**
     * Show a dialog with the provided certificate information.
     *
     * @param context The context this view should display in.
     * @param derData DER-encoded data representing a X509 certificate chain.
     */
    public static void showCertificateChain(Context context, byte[][] derData) {
        CertificateViewer viewer = new CertificateViewer(context);
        viewer.showCertificateChain(derData);
    }

    private CertificateViewer(Context context) {
        mContext = context;
        mViews = new ArrayList<LinearLayout>();
        mTitles = new ArrayList<String>();
        mPadding = (int) context.getResources().getDimension(
                R.dimen.certificate_viewer_padding) / 2;
    }

    // Show information about an array of DER-encoded data representing a X509 certificate chain.
    // A spinner will be displayed allowing the user to select which certificate to display.
    private void showCertificateChain(byte[][] derData) {
        for (int i = 0; i < derData.length; i++) {
            addCertificate(derData[i]);
        }
        ArrayAdapter<String> arrayAdapter = new ArrayAdapter<String>(mContext,
                android.R.layout.simple_spinner_item,
                mTitles);
        arrayAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);

        Spinner spinner = new Spinner(mContext);
        spinner.setAdapter(arrayAdapter);
        spinner.setOnItemSelectedListener(this);

        LinearLayout container = new LinearLayout(mContext);
        container.setOrientation(LinearLayout.VERTICAL);
        container.addView(spinner);

        for (int i = 0; i < mViews.size(); ++i) {
            LinearLayout certificateView = mViews.get(i);
            if (i != 0) {
                certificateView.setVisibility(LinearLayout.GONE);
            }
            container.addView(certificateView);
        }

        showDialogForView(container);
    }

    // Displays a dialog with scrolling for the given view.
    private void showDialogForView(View view) {
        Dialog dialog = new Dialog(mContext);
        dialog.setTitle(R.string.certtitle);
        ScrollView scrollView = new ScrollView(mContext);
        scrollView.addView(view);
        dialog.addContentView(scrollView,
                new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT,
                        LinearLayout.LayoutParams.MATCH_PARENT));
        dialog.show();
    }

    private void addCertificate(byte[] derData) {
        try {
            if (mCertificateFactory == null) {
                mCertificateFactory = CertificateFactory.getInstance(X_509);
            }
            Certificate cert = mCertificateFactory.generateCertificate(
                    new ByteArrayInputStream(derData));
            addCertificateDetails(cert, getDigest(derData, "SHA-256"), getDigest(derData, "SHA-1"));
        } catch (CertificateException e) {
            Log.e("CertViewer", "Error parsing certificate" + e.toString());
        }
    }

    private void addCertificateDetails(Certificate cert, byte[] sha256Digest, byte[] sha1Digest) {
        LinearLayout certificateView = new LinearLayout(mContext);
        mViews.add(certificateView);
        certificateView.setOrientation(LinearLayout.VERTICAL);

        X509Certificate x509 = (X509Certificate) cert;
        SslCertificate sslCert = new SslCertificate(x509);

        mTitles.add(sslCert.getIssuedTo().getCName());

        addSectionTitle(certificateView, nativeGetCertIssuedToText());
        addItem(certificateView, nativeGetCertInfoCommonNameText(),
                sslCert.getIssuedTo().getCName());
        addItem(certificateView, nativeGetCertInfoOrganizationText(),
                sslCert.getIssuedTo().getOName());
        addItem(certificateView, nativeGetCertInfoOrganizationUnitText(),
                sslCert.getIssuedTo().getUName());
        addItem(certificateView, nativeGetCertInfoSerialNumberText(),
                formatBytes(x509.getSerialNumber().toByteArray(), ':'));

        addSectionTitle(certificateView, nativeGetCertIssuedByText());
        addItem(certificateView, nativeGetCertInfoCommonNameText(),
                sslCert.getIssuedBy().getCName());
        addItem(certificateView, nativeGetCertInfoOrganizationText(),
                sslCert.getIssuedBy().getOName());
        addItem(certificateView, nativeGetCertInfoOrganizationUnitText(),
                sslCert.getIssuedBy().getUName());

        addSectionTitle(certificateView, nativeGetCertValidityText());
        java.text.DateFormat dateFormat = DateFormat.getDateFormat(mContext);
        addItem(certificateView, nativeGetCertIssuedOnText(),
                dateFormat.format(sslCert.getValidNotBeforeDate()));
        addItem(certificateView, nativeGetCertExpiresOnText(),
                dateFormat.format(sslCert.getValidNotAfterDate()));

        addSectionTitle(certificateView, nativeGetCertFingerprintsText());
        addItem(certificateView, nativeGetCertSHA256FingerprintText(),
                formatBytes(sha256Digest, ' '));
        addItem(certificateView, nativeGetCertSHA1FingerprintText(),
                formatBytes(sha1Digest, ' '));
    }

    private void addSectionTitle(LinearLayout certificateView, String label) {
        TextView title = addLabel(certificateView, label);
        title.setAllCaps(true);
    }

    private void addItem(LinearLayout certificateView, String label, String value) {
        if (value.isEmpty()) return;

        addLabel(certificateView, label);
        addValue(certificateView, value);
    }

    private TextView addLabel(LinearLayout certificateView, String label) {
        TextView t = new TextView(mContext);
        t.setPadding(mPadding, mPadding / 2, mPadding, 0);
        t.setText(label);
        t.setTypeface(Typeface.defaultFromStyle(Typeface.BOLD));
        certificateView.addView(t);
        return t;
    }

    private void addValue(LinearLayout certificateView, String value) {
        TextView t = new TextView(mContext);
        t.setText(value);
        t.setPadding(mPadding, 0, mPadding, mPadding / 2);
        certificateView.addView(t);
    }

    private static String formatBytes(byte[] bytes, char separator) {
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < bytes.length; i++) {
            sb.append(String.format("%02X", bytes[i]));
            if (i != bytes.length - 1) {
                sb.append(separator);
            }
        }
        return sb.toString();
    }

    private static byte[] getDigest(byte[] bytes, String algorithm) {
        try {
            MessageDigest md = MessageDigest.getInstance(algorithm);
            md.update(bytes);
            return md.digest();
        } catch (java.security.NoSuchAlgorithmException e) {
            return null;
        }
    }

    @Override
    public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
        for (int i = 0; i < mViews.size(); ++i) {
            mViews.get(i).setVisibility(
                    i == position ? LinearLayout.VISIBLE : LinearLayout.GONE);
        }
    }

    @Override
    public void onNothingSelected(AdapterView<?> parent) {
    }

    private static native String nativeGetCertIssuedToText();
    private static native String nativeGetCertInfoCommonNameText();
    private static native String nativeGetCertInfoOrganizationText();
    private static native String nativeGetCertInfoSerialNumberText();
    private static native String nativeGetCertInfoOrganizationUnitText();
    private static native String nativeGetCertIssuedByText();
    private static native String nativeGetCertValidityText();
    private static native String nativeGetCertIssuedOnText();
    private static native String nativeGetCertExpiresOnText();
    private static native String nativeGetCertFingerprintsText();
    private static native String nativeGetCertSHA256FingerprintText();
    private static native String nativeGetCertSHA1FingerprintText();
}