Question

我正在尝试从内部SSL服务器加载地图图块。 Android系统无法识别SSL证书的信任根。

W / o * .o * .t * .m * .MapTileDow *（2837）：IOException下载MapTile：/ 8/37/4： javax.net.ssl.SSLPeerUnverifiedException ：没有对等证书

我已经熟悉了这个问题，并在应用程序的其余部分based on this excellent SO answer中解决了这个问题。从本质上讲，我扩展了自己的SSLSocketFactory和X509TrustManager，它从与应用程序捆绑在一起的.bks文件中加载了我的SSL证书的信任根。为了创建一个安全的连接，我打电话给((HttpsURLConnection) connection).setSSLSocketFactory(mySSLSocketFactory)，并使用我的信任根证书验证证书。

我的问题是如何为osmdroid做同样的事情？我正在创建自己的XYTileSource，我在其中设置了地图图块的URL，文件扩展名，大小等。我看到osmdroid创建了它在MapTileDownloader下载地图图块图像的连接。我可以编写自己的替换类，以同样的方式解决SSL问题，但是如何告诉osmdroid使用我的自定义下载器而不是默认值？

Answer 1

事实证明，由于public MapView(Context context, int tileSizePixels, ResourceProxy resourceProxy, MapTileProviderBase aTileProvider) constrtuctor，这可以在不改变osmdroid源的情况下实现。

假设您已经拥有自定义类，例如 MySSLSocketFactory （extends javax.net.ssl.SSLSocketFactory），基本流程如下所示：

为MapTileDownloader创建一个插入式替换课程，以便使用 MySSLSocketFactory 的方式执行下载。我们称之为 MyTileDownloader 。
为MapTileProviderBasic创建实例化自定义MyTileDownloader的插入式替换类。我们称之为 MyTileProvider 。
将您的磁贴源实例化为new XYTileSource（无需编写自定义类）。
使用您的磁贴源实例实例化 MyTileProvider 。
使用您的磁贴提供程序实例实例化MapVew。

MySSLSocketFactory 留给读者练习。请参阅this post。

MyTileDownloader 看起来像这样：

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.UnknownHostException;

import javax.net.ssl.HttpsURLConnection;
import javax.net.ssl.SSLSocketFactory;

import org.osmdroid.tileprovider.MapTile;
import org.osmdroid.tileprovider.MapTileRequestState;
import org.osmdroid.tileprovider.modules.IFilesystemCache;
import org.osmdroid.tileprovider.modules.INetworkAvailablityCheck;
import org.osmdroid.tileprovider.modules.MapTileDownloader;
import org.osmdroid.tileprovider.modules.MapTileModuleProviderBase;
import org.osmdroid.tileprovider.tilesource.BitmapTileSourceBase.LowMemoryException;
import org.osmdroid.tileprovider.tilesource.ITileSource;
import org.osmdroid.tileprovider.tilesource.OnlineTileSourceBase;
import org.osmdroid.tileprovider.util.StreamUtils;

import android.graphics.drawable.Drawable;
import android.text.TextUtils;
import android.util.Log;

/**
 * A drop-in replacement for {@link MapTileDownloader}. This loads tiles from an
 * HTTP or HTTPS server, making use of a custom {@link SSLSocketFactory} for SSL
 * peer verification.
 */
public class MyTileDownloader extends MapTileModuleProviderBase {
    private static final String TAG = "MyMapTileDownloader";

    protected OnlineTileSourceBase mTileSource;
    protected final IFilesystemCache mFilesystemCache;
    protected final INetworkAvailablityCheck mNetworkAvailablityCheck;
    protected final SSLSocketFactory mSSLSocketFactory;

    public MyTileDownloader(ITileSource pTileSource,
            IFilesystemCache pFilesystemCache,
            INetworkAvailablityCheck pNetworkAvailablityCheck,
            SSLSocketFactory pSSLSocketFactory) {
        super(4, TILE_DOWNLOAD_MAXIMUM_QUEUE_SIZE);
        setTileSource(pTileSource);
        mFilesystemCache = pFilesystemCache;
        mNetworkAvailablityCheck = pNetworkAvailablityCheck;
        mSSLSocketFactory = pSSLSocketFactory;
    }

    public ITileSource getTileSource() {
        return mTileSource;
    }

    @Override
    public void setTileSource(final ITileSource tileSource) {
        // We are only interested in OnlineTileSourceBase tile sources
        if (tileSource instanceof OnlineTileSourceBase)
            mTileSource = (OnlineTileSourceBase) tileSource;
        else
            mTileSource = null;
    }

    @Override
    public boolean getUsesDataConnection() {
        return true;
    }

    @Override
    protected String getName() {
        return "Online Tile Download Provider";
    }

    @Override
    protected String getThreadGroupName() {
        return "downloader";
    }

    @Override
    public int getMinimumZoomLevel() {
        return (mTileSource != null ? mTileSource.getMinimumZoomLevel()
                : MINIMUM_ZOOMLEVEL);
    }

    @Override
    public int getMaximumZoomLevel() {
        return (mTileSource != null ? mTileSource.getMaximumZoomLevel()
                : MAXIMUM_ZOOMLEVEL);
    }

    @Override
    protected Runnable getTileLoader() {
        return new TileLoader();
    };

    private class TileLoader extends MapTileModuleProviderBase.TileLoader {
        @Override
        public Drawable loadTile(final MapTileRequestState aState)
                throws CantContinueException {
            if (mTileSource == null)
                return null;

            InputStream in = null;
            OutputStream out = null;
            final MapTile tile = aState.getMapTile();

            try {
                if (mNetworkAvailablityCheck != null
                        && !mNetworkAvailablityCheck.getNetworkAvailable()) {
                    if (DEBUGMODE)
                        Log.d(TAG, "Skipping " + getName()
                                + " due to NetworkAvailabliltyCheck.");
                    return null;
                }

                final String tileURLString = mTileSource.getTileURLString(tile);
                if (DEBUGMODE)
                    Log.d(TAG, "Downloading Maptile from url: " + tileURLString);

                if (TextUtils.isEmpty(tileURLString))
                    return null;

                // Create an HttpURLConnection to download the tile
                URL url = new URL(tileURLString);
                HttpURLConnection connection = (HttpURLConnection) url
                        .openConnection();
                connection.setConnectTimeout(30000);
                connection.setReadTimeout(30000);

                // Use our custom SSLSocketFactory for secure connections
                if ("https".equalsIgnoreCase(url.getProtocol()))
                    ((HttpsURLConnection) connection)
                            .setSSLSocketFactory(mSSLSocketFactory);

                // Open the input stream
                in = new BufferedInputStream(connection.getInputStream(),
                        StreamUtils.IO_BUFFER_SIZE);

                // Check to see if we got success
                if (connection.getResponseCode() != 200) {
                    Log.w(TAG, "Problem downloading MapTile: " + tile
                            + " HTTP response: " + connection.getHeaderField(0));
                    return null;
                }

                // Read the tile into an in-memory byte array
                final ByteArrayOutputStream dataStream = new ByteArrayOutputStream();
                out = new BufferedOutputStream(dataStream,
                        StreamUtils.IO_BUFFER_SIZE);
                StreamUtils.copy(in, out);
                out.flush();
                final byte[] data = dataStream.toByteArray();
                final ByteArrayInputStream byteStream = new ByteArrayInputStream(
                        data);

                // Save the data to the filesystem cache
                if (mFilesystemCache != null) {
                    mFilesystemCache.saveFile(mTileSource, tile, byteStream);
                    byteStream.reset();
                }
                final Drawable result = mTileSource.getDrawable(byteStream);
                return result;

            } catch (final UnknownHostException e) {
                Log.w(TAG, "UnknownHostException downloading MapTile: " + tile
                        + " : " + e);
                throw new CantContinueException(e);

            } catch (final LowMemoryException e) {
                Log.w(TAG, "LowMemoryException downloading MapTile: " + tile
                        + " : " + e);
                throw new CantContinueException(e);

            } catch (final FileNotFoundException e) {
                Log.w(TAG, "Tile not found: " + tile + " : " + e);

            } catch (final IOException e) {
                Log.w(TAG, "IOException downloading MapTile: " + tile + " : "
                        + e);

            } catch (final Throwable e) {
                Log.e(TAG, "Error downloading MapTile: " + tile, e);

            } finally {
                StreamUtils.closeStream(in);
                StreamUtils.closeStream(out);
            }
            return null;
        }

        @Override
        protected void tileLoaded(final MapTileRequestState pState,
                final Drawable pDrawable) {
            // Don't return the tile Drawable because we'll wait for the fs
            // provider to ask for it. This prevent flickering when a load
            // of delayed downloads complete for tiles that we might not
            // even be interested in any more.
            super.tileLoaded(pState, null);
        }
    }
}

MyTileProvider 看起来像这样。

请注意，您需要一种方法来访问此类中 MySSLSocketFactory 的实例。这留给读者练习。我使用app.getSSLSocketFactory()执行此操作，其中app是extends Application的自定义类的实例，但您的里程可能会有所不同。

import javax.net.ssl.SSLSocketFactory;

import org.osmdroid.tileprovider.IMapTileProviderCallback;
import org.osmdroid.tileprovider.IRegisterReceiver;
import org.osmdroid.tileprovider.MapTileProviderArray;
import org.osmdroid.tileprovider.MapTileProviderBasic;
import org.osmdroid.tileprovider.modules.INetworkAvailablityCheck;
import org.osmdroid.tileprovider.modules.MapTileFileArchiveProvider;
import org.osmdroid.tileprovider.modules.MapTileFilesystemProvider;
import org.osmdroid.tileprovider.modules.NetworkAvailabliltyCheck;
import org.osmdroid.tileprovider.modules.TileWriter;
import org.osmdroid.tileprovider.tilesource.ITileSource;
import org.osmdroid.tileprovider.util.SimpleRegisterReceiver;

import android.content.Context;

/**
 * A drop-in replacement for {@link MapTileProviderBasic}. This top-level tile
 * provider implements a basic tile request chain which includes a
 * {@link MapTileFilesystemProvider} (a file-system cache), a
 * {@link MapTileFileArchiveProvider} (archive provider), and a
 * {@link MyTileDownloader} (downloads map tiles via tile source).
 */
public class MyTileProvider extends MapTileProviderArray implements
        IMapTileProviderCallback {
    public MyTileProvider(final Context pContext, final ITileSource pTileSource) {
        this(new SimpleRegisterReceiver(pContext),
                new NetworkAvailabliltyCheck(pContext), pTileSource, app
                        .getSSLSocketFactory());
    }

    protected MyTileProvider(final IRegisterReceiver pRegisterReceiver,
            final INetworkAvailablityCheck aNetworkAvailablityCheck,
            final ITileSource pTileSource,
            final SSLSocketFactory pSSLSocketFactory) {
        super(pTileSource, pRegisterReceiver);

        // Look for raw tiles on the file system
        final MapTileFilesystemProvider fileSystemProvider = new MapTileFilesystemProvider(
                pRegisterReceiver, pTileSource);
        mTileProviderList.add(fileSystemProvider);

        // Look for tile archives on the file system
        final MapTileFileArchiveProvider archiveProvider = new MapTileFileArchiveProvider(
                pRegisterReceiver, pTileSource);
        mTileProviderList.add(archiveProvider);

        // Look for raw tiles on the Internet
        final TileWriter tileWriter = new TileWriter();
        final MyTileDownloader downloaderProvider = new MyTileDownloader(
                pTileSource, tileWriter, aNetworkAvailablityCheck,
                pSSLSocketFactory);
        mTileProviderList.add(downloaderProvider);
    }
}

最后，实例化看起来像这样：

XYTileSource tileSource = new XYTileSource("MapQuest", null, 3, 8, 256, ".jpg",
    "https://10.0.0.1/path/to/your/map/tiles/");
MapTileProviderBase tileProvider = new MyTileProvider(context, tileSource);
ResourceProxy resourceProxy = new DefaultResourceProxyImpl(context);
MapView mapView = new MapView(context, 256, resourceProxy, tileProvider);

Answer 2

我不使用osmdroid，但除非它有公共接口来替换下载程序类，否则最好的办法是获取源代码并对其进行修补以使其可配置或使用您自己的下载程序类。如果MapTileDownloader实现了某个接口，你可以做一些反射伏都教来在运行时替换它，但这可能有未知的副作用。

如何向osmdroid的MapTileDownloader添加自定义SSL证书验证？

2 个答案: