support prefetched metadata & refactor

src/main/java/org/to2mbn/authlibinjector/AuthlibInjector.java

@@ -2,12 +2,16 @@ package org.to2mbn.authlibinjector;
 
 import static java.util.Optional.empty;
 import static java.util.Optional.of;
+import static org.to2mbn.authlibinjector.util.IOUtils.readURL;
 import java.io.IOException;
 import java.lang.instrument.ClassFileTransformer;
 import java.text.MessageFormat;
 import java.util.Optional;
 import java.util.function.Consumer;
 import org.to2mbn.authlibinjector.transform.ClassTransformer;
+import org.to2mbn.authlibinjector.transform.SkinWhitelistTransformUnit;
+import org.to2mbn.authlibinjector.transform.YggdrasilApiTransformUnit;
+import org.to2mbn.authlibinjector.transform.YggdrasilKeyTransformUnit;
 
 public final class AuthlibInjector {
 
@@ -19,60 +23,82 @@ public final class AuthlibInjector {
 	private AuthlibInjector() {}
 
 	private static boolean booted = false;
+	private static boolean debug = "true".equals(System.getProperty("org.to2mbn.authlibinjector.debug"));
 
-	public static void log(String message, Object... args) {
+	public static void info(String message, Object... args) {
 		System.err.println("[authlib-injector] " + MessageFormat.format(message, args));
 	}
 
+	public static void debug(String message, Object... args) {
+		if (debug) {
+			info(message, args);
+		}
+	}
+
 	public static void bootstrap(Consumer<ClassFileTransformer> transformerRegistry) {
 		if (booted) {
-			log("already booted, skipping");
+			info("already booted, skipping");
 			return;
 		}
 		booted = true;
 
-		Optional<InjectorConfig> optionalConfig = configure();
+		Optional<YggdrasilConfiguration> optionalConfig = configure();
 		if (!optionalConfig.isPresent()) {
-			log("no config is found, exiting");
+			info("no config available");
 			return;
 		}
 
-		InjectorConfig config = optionalConfig.get();
+		transformerRegistry.accept(createTransformer(optionalConfig.get()));
+	}
+
+	private static Optional<YggdrasilConfiguration> configure() {
+		String apiRoot = System.getProperty("org.to2mbn.authlibinjector.config");
+		if (apiRoot == null) return empty();
+		info("api root: {0}", apiRoot);
+
+		String metadataResponse = System.getProperty("org.to2mbn.authlibinjector.config.prefetched");
+
+		if (metadataResponse == null) {
+			info("fetching metadata");
+			try {
+				metadataResponse = readURL(apiRoot);
+			} catch (IOException e) {
+				info("unable to fetch metadata: {0}", e);
+				return empty();
+			}
+
+		} else {
+			info("prefetched metadata detected");
+		}
+
+		debug("metadata: {0}", metadataResponse);
+
+		YggdrasilConfiguration configuration;
+		try {
+			configuration = YggdrasilConfiguration.parse(apiRoot, metadataResponse);
+		} catch (IOException e) {
+			info("unable to parse metadata: {0}\n"
+					+ "metadata to parse:\n"
+					+ "{1}",
+					e, metadataResponse);
+			return empty();
+		}
+		debug("parsed metadata: {0}", configuration);
+		return of(configuration);
+	}
+
+	private static ClassTransformer createTransformer(YggdrasilConfiguration config) {
 		ClassTransformer transformer = new ClassTransformer();
-
-		if (config.isDebug()) transformer.debug = true;
-
+		transformer.debugSaveClass = debug;
 		for (String ignore : nonTransformablePackages)
 			transformer.ignores.add(ignore);
 
-		config.applyTransformers(transformer.units);
-		transformerRegistry.accept(transformer);
-	}
+		transformer.units.add(new YggdrasilApiTransformUnit(config.getApiRoot()));
+		transformer.units.add(new SkinWhitelistTransformUnit(config.getSkinDomains().toArray(new String[0])));
+		config.getDecodedPublickey().ifPresent(
+				key -> transformer.units.add(new YggdrasilKeyTransformUnit(key.getEncoded())));
 
-	private static Optional<InjectorConfig> configure() {
-		String url = System.getProperty("org.to2mbn.authlibinjector.config");
-		if (url == null) {
-			return empty();
-		}
-		log("trying to config remotely: {0}", url);
-
-		InjectorConfig config = new InjectorConfig();
-		config.setDebug("true".equals(System.getProperty("org.to2mbn.authlibinjector.debug")));
-
-		RemoteConfiguration remoteConfig;
-		try {
-			remoteConfig = RemoteConfiguration.fetch(url);
-		} catch (IOException e) {
-			log("unable to configure remotely: {0}", e);
-			return empty();
-		}
-
-		if (config.isDebug()) {
-			log("fetched remote config: {0}", remoteConfig);
-		}
-
-		remoteConfig.applyToInjectorConfig(config);
-		return of(config);
+		return transformer;
 	}
 
 }

src/main/java/org/to2mbn/authlibinjector/InjectorConfig.java

@@ -1,56 +0,0 @@
-package org.to2mbn.authlibinjector;
-
-import static org.to2mbn.authlibinjector.util.KeyUtils.decodePublicKey;
-import java.util.List;
-import org.to2mbn.authlibinjector.transform.SkinWhitelistTransformUnit;
-import org.to2mbn.authlibinjector.transform.TransformUnit;
-import org.to2mbn.authlibinjector.transform.YggdrasilApiTransformUnit;
-import org.to2mbn.authlibinjector.transform.YggdrasilKeyTransformUnit;
-
-public class InjectorConfig {
-
-	private String apiRoot;
-	private List<String> skinWhitelistDomains;
-	private String publicKey;
-	private boolean debug;
-
-	public String getApiRoot() {
-		return apiRoot;
-	}
-
-	public void setApiRoot(String apiRoot) {
-		this.apiRoot = apiRoot;
-	}
-
-	public List<String> getSkinWhitelistDomains() {
-		return skinWhitelistDomains;
-	}
-
-	public void setSkinWhitelistDomains(List<String> skinWhitelistDomains) {
-		this.skinWhitelistDomains = skinWhitelistDomains;
-	}
-
-	public String getPublicKey() {
-		return publicKey;
-	}
-
-	public void setPublicKey(String publicKey) {
-		this.publicKey = publicKey;
-	}
-
-	public boolean isDebug() {
-		return debug;
-	}
-
-	public void setDebug(boolean debug) {
-		this.debug = debug;
-	}
-
-	public void applyTransformers(List<TransformUnit> units) {
-		units.add(new YggdrasilApiTransformUnit(apiRoot));
-		units.add(new SkinWhitelistTransformUnit(skinWhitelistDomains.toArray(new String[0])));
-		if (publicKey != null) {
-			units.add(new YggdrasilKeyTransformUnit(decodePublicKey(publicKey)));
-		}
-	}
-}

src/main/java/org/to2mbn/authlibinjector/YggdrasilConfiguration.java

@@ -6,8 +6,6 @@ import static java.util.Objects.requireNonNull;
 import static java.util.Optional.empty;
 import static java.util.Optional.of;
 import static java.util.Optional.ofNullable;
-import static org.to2mbn.authlibinjector.util.HttpRequester.http;
-import static org.to2mbn.authlibinjector.util.IOUtils.asJson;
 import static org.to2mbn.authlibinjector.util.KeyUtils.decodePublicKey;
 import static org.to2mbn.authlibinjector.util.KeyUtils.loadX509PublicKey;
 import java.io.IOException;
@@ -21,13 +19,13 @@ import java.util.TreeMap;
 import org.to2mbn.authlibinjector.internal.org.json.JSONException;
 import org.to2mbn.authlibinjector.internal.org.json.JSONObject;
 
-public class RemoteConfiguration {
+public class YggdrasilConfiguration {
 
-	public static RemoteConfiguration fetch(String apiRoot) throws IOException {
+	public static YggdrasilConfiguration parse(String apiRoot, String metadataResponse) throws IOException {
 		if (!apiRoot.endsWith("/")) apiRoot += "/";
 
 		try {
-			JSONObject response = asJson(http.request("GET", apiRoot));
+			JSONObject response = new JSONObject(metadataResponse);
 
 			List<String> skinDomains = new ArrayList<>();
 			ofNullable(response.optJSONArray("skinDomains"))
@@ -54,7 +52,7 @@ public class RemoteConfiguration {
 					.map(JSONObject::toMap)
 					.ifPresent(it -> it.forEach((k, v) -> meta.put(k, String.valueOf(v))));
 
-			return new RemoteConfiguration(apiRoot, unmodifiableList(skinDomains), signaturePublickey, unmodifiableMap(meta), decodedPublickey);
+			return new YggdrasilConfiguration(apiRoot, unmodifiableList(skinDomains), signaturePublickey, unmodifiableMap(meta), decodedPublickey);
 		} catch (JSONException e) {
 			throw new IOException("Invalid json", e);
 		}
@@ -66,7 +64,7 @@ public class RemoteConfiguration {
 	private Optional<PublicKey> decodedPublickey;
 	private Map<String, String> meta;
 
-	public RemoteConfiguration(String apiRoot, List<String> skinDomains, Optional<String> signaturePublickey, Map<String, String> meta, Optional<PublicKey> decodedPublickey) {
+	public YggdrasilConfiguration(String apiRoot, List<String> skinDomains, Optional<String> signaturePublickey, Map<String, String> meta, Optional<PublicKey> decodedPublickey) {
 		this.apiRoot = requireNonNull(apiRoot);
 		this.skinDomains = requireNonNull(skinDomains);
 		this.signaturePublickey = requireNonNull(signaturePublickey);
@@ -94,14 +92,8 @@ public class RemoteConfiguration {
 		return decodedPublickey;
 	}
 
-	public void applyToInjectorConfig(InjectorConfig config) {
-		config.setApiRoot(apiRoot);
-		config.setPublicKey(signaturePublickey.orElse(null));
-		config.setSkinWhitelistDomains(skinDomains);
-	}
-
 	@Override
 	public String toString() {
-		return "RemoteConfiguration [apiRoot=" + apiRoot + ", skinDomains=" + skinDomains + ", signaturePublickey=" + signaturePublickey + ", meta=" + meta + "]";
+		return "YggdrasilConfiguration [apiRoot=" + apiRoot + ", skinDomains=" + skinDomains + ", signaturePublickey=" + signaturePublickey + ", meta=" + meta + "]";
 	}
 }

src/main/java/org/to2mbn/authlibinjector/javaagent/AuthlibInjectorPremain.java

@@ -1,14 +1,14 @@
 package org.to2mbn.authlibinjector.javaagent;
 
 import static org.to2mbn.authlibinjector.AuthlibInjector.bootstrap;
-import static org.to2mbn.authlibinjector.AuthlibInjector.log;
+import static org.to2mbn.authlibinjector.AuthlibInjector.info;
 import java.lang.instrument.Instrumentation;
 
 public class AuthlibInjectorPremain {
 
 	public static void premain(String arg, Instrumentation instrumentation) {
 		try {
-			log("launched from javaagent");
+			info("launched from javaagent");
 			if (arg != null && !arg.isEmpty()) {
 				System.setProperty("org.to2mbn.authlibinjector.config", arg);
 			}

src/main/java/org/to2mbn/authlibinjector/transform/ClassTransformer.java

@@ -1,6 +1,7 @@
 package org.to2mbn.authlibinjector.transform;
 
-import static org.to2mbn.authlibinjector.AuthlibInjector.log;
+import static org.to2mbn.authlibinjector.AuthlibInjector.debug;
+import static org.to2mbn.authlibinjector.AuthlibInjector.info;
 import java.io.IOException;
 import java.lang.instrument.ClassFileTransformer;
 import java.lang.instrument.IllegalClassFormatException;
@@ -21,7 +22,7 @@ public class ClassTransformer implements ClassFileTransformer {
 
 	public List<TransformUnit> units = new ArrayList<>();
 	public Set<String> ignores = new HashSet<>();
-	public boolean debug;
+	public boolean debugSaveClass;
 
 	private static class TransformHandle {
 
@@ -51,7 +52,7 @@ public class ClassTransformer implements ClassFileTransformer {
 				ClassReader reader = new ClassReader(classBuffer);
 				reader.accept(optionalVisitor.get(), 0);
 				if (currentModified) {
-					log("transform {0} using {1}", className, unit);
+					info("transform {0} using {1}", className, unit);
 					modified = true;
 					classBuffer = writer.toByteArray();
 				}
@@ -82,18 +83,16 @@ public class ClassTransformer implements ClassFileTransformer {
 				units.forEach(handle::accept);
 				if (handle.getResult().isPresent()) {
 					byte[] classBuffer = handle.getResult().get();
-					if (debug) {
+					if (debugSaveClass) {
 						saveClassFile(className, classBuffer);
 					}
 					return classBuffer;
 				} else {
-					if (debug) {
-						log("no transform performed on {0}", className);
-					}
+					debug("no transform performed on {0}", className);
 					return null;
 				}
 			} catch (Throwable e) {
-				log("unable to transform {0}: {1}", internalClassName, e);
+				info("unable to transform {0}: {1}", internalClassName, e);
 				e.printStackTrace();
 			}
 		}
@@ -104,7 +103,7 @@ public class ClassTransformer implements ClassFileTransformer {
 		try {
 			Files.write(Paths.get(className + "_dump.class"), classBuffer, StandardOpenOption.CREATE, StandardOpenOption.TRUNCATE_EXISTING);
 		} catch (IOException e) {
-			log("unable to dump class {0}: {1}", className, e);
+			info("unable to dump class {0}: {1}", className, e);
 			e.printStackTrace();
 		}
 	}

src/main/java/org/to2mbn/authlibinjector/transform/LdcTransformUnit.java

@@ -1,7 +1,7 @@
 package org.to2mbn.authlibinjector.transform;
 
 import static org.objectweb.asm.Opcodes.ASM6;
-import static org.to2mbn.authlibinjector.AuthlibInjector.log;
+import static org.to2mbn.authlibinjector.AuthlibInjector.info;
 import java.util.Optional;
 import java.util.function.Function;
 import org.objectweb.asm.ClassVisitor;
@@ -29,7 +29,7 @@ public class LdcTransformUnit implements TransformUnit {
 							Optional<String> transformed = ldcMapper.apply((String) cst);
 							if (transformed.isPresent() && !transformed.get().equals(cst)) {
 								modifiedCallback.run();
-								log("transform [{0}] to [{1}]", cst, transformed.get());
+								info("transform [{0}] to [{1}]", cst, transformed.get());
 								super.visitLdcInsn(transformed.get());
 							} else {
 								super.visitLdcInsn(cst);

src/main/java/org/to2mbn/authlibinjector/util/HttpRequester.java

@@ -1,114 +0,0 @@
-package org.to2mbn.authlibinjector.util;
-
-import static java.nio.charset.StandardCharsets.UTF_8;
-import static org.to2mbn.authlibinjector.util.IOUtils.asString;
-import java.io.IOException;
-import java.io.InputStream;
-import java.io.OutputStream;
-import java.net.HttpURLConnection;
-import java.net.URL;
-import java.util.Map;
-
-public class HttpRequester {
-
-	/** Common http requester */
-	public static final HttpRequester http = new HttpRequester();
-
-	private int timeout = 15000;
-
-	public int getTimeout() {
-		return timeout;
-	}
-
-	public void setTimeout(int timeout) {
-		this.timeout = timeout;
-	}
-
-	public String request(String method, String url) throws IOException {
-		return request(method, url, null);
-	}
-
-	public String request(String method, String url, Map<String, String> headers) throws IOException {
-		HttpURLConnection conn = createConnection(url, headers);
-		conn.setRequestMethod(method);
-		try {
-			conn.connect();
-			try (InputStream in = conn.getInputStream()) {
-				return asString(in);
-			}
-		} catch (IOException e) {
-			try (InputStream in = conn.getErrorStream()) {
-				return readErrorStream(in, e);
-			}
-		} finally {
-			conn.disconnect();
-		}
-	}
-
-	public String requestWithPayload(String method, String url, Object payload, String contentType) throws IOException {
-		return requestWithPayload(method, url, payload, contentType, null);
-	}
-
-	public String requestWithPayload(String method, String url, Object payload, String contentType, Map<String, String> headers) throws IOException {
-		byte[] bytePayload;
-		if (payload instanceof byte[]) {
-			bytePayload = (byte[]) payload;
-		} else if (payload == null) {
-			bytePayload = new byte[0];
-		} else {
-			bytePayload = String.valueOf(payload).getBytes(UTF_8);
-		}
-
-		HttpURLConnection conn = createConnection(url, headers);
-		conn.setRequestMethod(method);
-		conn.setRequestProperty("Content-Type", contentType);
-		conn.setRequestProperty("Content-Length", String.valueOf(bytePayload.length));
-		conn.setDoOutput(true);
-
-		try {
-			conn.connect();
-			try (OutputStream out = conn.getOutputStream()) {
-				out.write(bytePayload);
-			}
-			try (InputStream in = conn.getInputStream()) {
-				return asString(in);
-			}
-		} catch (IOException e) {
-			try (InputStream in = conn.getErrorStream()) {
-				return readErrorStream(in, e);
-			}
-		} finally {
-			conn.disconnect();
-		}
-	}
-
-	private String readErrorStream(InputStream in, IOException e) throws IOException {
-		if (in == null)
-			throw e;
-
-		try {
-			return asString(in);
-		} catch (IOException e1) {
-			if (e != e1)
-				e1.addSuppressed(e);
-
-			throw e1;
-		}
-	}
-
-	private HttpURLConnection createConnection(String url, Map<String, String> headers) throws IOException {
-		HttpURLConnection conn = createConnection(new URL(url));
-		if (headers != null)
-			headers.forEach((key, value) -> conn.setRequestProperty(key, value));
-		return conn;
-	}
-
-	private HttpURLConnection createConnection(URL url) throws IOException {
-		HttpURLConnection conn = (HttpURLConnection) url.openConnection();
-		conn.setConnectTimeout(timeout);
-		conn.setReadTimeout(timeout);
-		conn.setUseCaches(false);
-		return conn;
-	}
-
-}

src/main/java/org/to2mbn/authlibinjector/util/IOUtils.java

@@ -6,11 +6,16 @@ import java.io.IOException;
 import java.io.InputStream;
 import java.io.InputStreamReader;
 import java.io.Reader;
-import org.to2mbn.authlibinjector.internal.org.json.JSONException;
-import org.to2mbn.authlibinjector.internal.org.json.JSONObject;
+import java.net.URL;
 
 public final class IOUtils {
 
+	public static String readURL(String url) throws IOException {
+		try (InputStream in = new URL(url).openStream()) {
+			return asString(in);
+		}
+	}
+
 	public static String asString(InputStream in) throws IOException {
 		CharArrayWriter w = new CharArrayWriter();
 		Reader reader = new InputStreamReader(in, UTF_8);
@@ -22,10 +27,6 @@ public final class IOUtils {
 		return new String(w.toCharArray());
 	}
 
-	public static JSONObject asJson(String data) throws JSONException {
-		return new JSONObject(data);
-	}
-
 	private IOUtils() {}
 
 }