EssentialsUpdate WIP

1 files changed, 204 insertions, 0 deletions

diff --git a/EssentialsUpdate/src/com/earth2me/essentials/update/UpdateFile.java b/EssentialsUpdate/src/com/earth2me/essentials/update/UpdateFile.java
new file mode 100644
index 000000000..8f34bffc4
--- /dev/null
+++ b/EssentialsUpdate/src/com/earth2me/essentials/update/UpdateFile.java
@@ -0,0 +1,204 @@
+package com.earth2me.essentials.update;
+
+import java.io.BufferedInputStream;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.math.BigInteger;
+import java.security.KeyFactory;
+import java.security.PublicKey;
+import java.security.Signature;
+import java.security.spec.X509EncodedKeySpec;
+import java.util.Collections;
+import java.util.Map;
+import java.util.TreeMap;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+import org.bukkit.plugin.Plugin;
+import org.bukkit.configuration.file.YamlConfiguration;
+
+
+public class UpdateFile
+{
+	private final static Logger LOGGER = Logger.getLogger("Minecraft");
+	private final static String UPDATE_URL = "http://goo.gl/67jev";
+	private final static BigInteger PUBLIC_KEY = new BigInteger("5ha6a2d4qdy17ttkg8evh74sl5a87djojwenu12k1lvy8ui6003e6l06rntczpoh99mhc3txj8mqlxw111oyy9yl7s7qpyluyzix3j1odxrxx4u52gxvyu6qiteapczkzvi7rxgeqsozz7b19rdx73a7quo9ybwpz1cr82r7x5k0pg2a73pjjsv2j1awr13azo7klrcxp9y5xxwf5qv1s3tw4zqftli18u0ek5qkbzfbgk1v5n2f11pkwwk6p0mibrn26wnjbv11vyiqgu95o7busmt6vf5q7grpcenl637w83mbin56s3asj1131b2mscj9xep3cbj7la9tgsxl5bj87vzy8sk2d34kzwqdqgh9nry43nqqus12l1stmiv184r8r3jcy8w43e8h1u1mzklldb5eytkuhayqik8l3ns04hwt8sgacvw534be8sx26qrn5s1", 36);
+	private final transient File file;
+	private transient YamlConfiguration updateConfig;
+	private final transient Plugin plugin;
+	private final transient TreeMap<Version, VersionInfo> versions = new TreeMap<Version, VersionInfo>();
+
+	public UpdateFile(final Plugin plugin)
+	{
+		this.plugin = plugin;
+		final long lastUpdate = Long.parseLong(plugin.getConfig().getString("lastupdate", "0"));
+		file = new File(plugin.getDataFolder(), "update.yml");
+		if (lastUpdate < System.currentTimeMillis() - 1000 * 60 * 60 * 6 || !file.exists())
+		{
+			if (file.exists() && !file.delete())
+			{
+				LOGGER.log(Level.SEVERE, "Could not delete file update.yml!");
+				return;
+			}
+			if (!downloadFile() || !checkFile())
+			{
+				LOGGER.log(Level.SEVERE, "Could not download and verify file update.yml!");
+				return;
+			}
+		}
+		try
+		{
+			readVersions();
+		}
+		catch (Exception ex)
+		{
+			LOGGER.log(Level.SEVERE, "Could not load update.yml!");
+			return;
+		}
+	}
+
+	private boolean downloadFile()
+	{
+		GetFile getFile;
+		try
+		{
+			getFile = new GetFile(UPDATE_URL);
+			getFile.saveTo(file);
+			plugin.getConfig().set("lastupdate", System.currentTimeMillis());
+			plugin.getConfig().save(new File(plugin.getDataFolder(),"config.yml"));
+			return true;
+		}
+		catch (IOException ex)
+		{
+			LOGGER.log(Level.SEVERE, "Error while downloading update.yml", ex);
+			return false;
+		}
+	}
+
+	private boolean checkFile()
+	{
+		BufferedInputStream bis = null;
+		try
+		{
+			bis = new BufferedInputStream(new FileInputStream(file));
+			if (bis.read() != '#')
+			{
+				throw new IOException("File has to start with #");
+			}
+			final StringBuilder length = new StringBuilder();
+			final StringBuilder signature = new StringBuilder();
+			boolean isSignature = false;
+			do
+			{
+				final int cur = bis.read();
+				if (cur == -1)
+				{
+					break;
+				}
+				if (cur == ':')
+				{
+					isSignature = true;
+				}
+				else if (cur == '\n')
+				{
+					break;
+				}
+				else if ((cur >= '0' && cur <= '9')
+						 || (cur >= 'a' && cur <= 'z'))
+				{
+					if (isSignature)
+					{
+						signature.append((char)cur);
+					}
+					else
+					{
+						length.append((char)cur);
+					}
+				}
+				else
+				{
+					throw new IOException("Illegal character in signature!");
+				}
+			}
+			while (true);
+			if (length.length() == 0 || signature.length() == 0)
+			{
+				throw new IOException("Broken signature!");
+			}
+			final int sigLength = new BigInteger(length.toString(), 36).intValue();
+			if (sigLength < 0 || sigLength > 2048)
+			{
+				throw new IOException("Invalid signature length!");
+			}
+			final byte[] sigBytes = new BigInteger(signature.toString(), 36).toByteArray();
+			if (sigLength < sigBytes.length)
+			{
+				throw new IOException("Length is less then available bytes.");
+			}
+			byte[] realBytes;
+			if (sigLength == sigBytes.length)
+			{
+				realBytes = sigBytes;
+			}
+			else
+			{
+				realBytes = new byte[sigLength];
+				System.arraycopy(sigBytes, 0, realBytes, sigLength - sigBytes.length, sigBytes.length);
+			}
+			final X509EncodedKeySpec pubKeySpec = new X509EncodedKeySpec(PUBLIC_KEY.toByteArray());
+			final KeyFactory keyFactory = KeyFactory.getInstance("RSA");
+			final PublicKey pubKey = keyFactory.generatePublic(pubKeySpec);
+			final Signature rsa = Signature.getInstance("SHA256withRSA");
+			rsa.initVerify(pubKey);
+			final byte[] buffer = new byte[2048];
+			int readLength;
+			do
+			{
+				readLength = bis.read(buffer);
+				if (readLength >= 0)
+				{
+					rsa.update(buffer, 0, readLength);
+				}
+			}
+			while (readLength >= 0);
+			return rsa.verify(realBytes);
+		}
+		catch (Exception ex)
+		{
+			LOGGER.log(Level.SEVERE, ex.getMessage(), ex);
+		}
+		finally
+		{
+			try
+			{
+				if (bis != null)
+				{
+					bis.close();
+				}
+			}
+			catch (IOException ex)
+			{
+				LOGGER.log(Level.SEVERE, ex.getMessage(), ex);
+			}
+		}
+		return false;
+	}
+
+	private void readVersions() throws Exception
+	{
+		updateConfig = new YamlConfiguration();
+		updateConfig.load(file);
+		versions.clear();
+		for (String versionString : updateConfig.getKeys(false))
+		{
+			final Version version = new Version(versionString);
+			final VersionInfo info = new VersionInfo(updateConfig, versionString);
+			versions.put(version, info);
+		}
+	}
+
+	public Map<Version, VersionInfo> getVersions()
+	{
+		return Collections.unmodifiableMap(versions.descendingMap());
+	}
+}