1 files changed, 133 insertions, 0 deletions
diff --git a/bundles/org.eclipse.osgi/container/src/org/eclipse/osgi/internal/signedcontent/BundleToJarInputStream.java b/bundles/org.eclipse.osgi/container/src/org/eclipse/osgi/internal/signedcontent/BundleToJarInputStream.java
new file mode 100644
index 000000000..cb70bdbe5
--- /dev/null
+++ b/bundles/org.eclipse.osgi/container/src/org/eclipse/osgi/internal/signedcontent/BundleToJarInputStream.java
@@ -0,0 +1,133 @@
+/*******************************************************************************
+ * Copyright (c) 2021 IBM Corporation and others.
+ *
+ * This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License 2.0
+ * which accompanies this distribution, and is available at
+ * https://www.eclipse.org/legal/epl-2.0/
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ * Contributors:
+ *     IBM Corporation - initial API and implementation
+ *******************************************************************************/
+
+package org.eclipse.osgi.internal.signedcontent;
+
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.ArrayList;
+import java.util.Enumeration;
+import java.util.Iterator;
+import java.util.List;
+import java.util.jar.JarEntry;
+import java.util.jar.JarFile;
+import java.util.jar.JarOutputStream;
+import org.eclipse.osgi.storage.bundlefile.BundleEntry;
+import org.eclipse.osgi.storage.bundlefile.BundleFile;
+
+/*
+ * Converts a BundleFile into an input stream that is appropriate for
+ * creating a JarInputStream.
+ */
+public final class BundleToJarInputStream extends InputStream {
+	private final BundleFile bundlefile;
+	private final Iterator<String> entryPaths;
+	private final JarOutputStream jarOutput;
+	private final ByteArrayOutputStream nextEntryOutput = new ByteArrayOutputStream();
+
+	private ByteArrayInputStream nextEntryInput = null;
+
+	public BundleToJarInputStream(BundleFile bundleFile) throws IOException {
+		this.bundlefile = bundleFile;
+		List<String> entries = new ArrayList<>();
+		int signatureFileCnt = 0;
+		for (Enumeration<String> ePaths = bundleFile.getEntryPaths("", true); ePaths.hasMoreElements();) { //$NON-NLS-1$
+			String entry = ePaths.nextElement();
+			if (entry.equals(JarFile.MANIFEST_NAME)) {
+				// this is always read into the stream first and entries follow
+				entries.add(0, entry);
+				signatureFileCnt++;
+
+			} else if (isSignatureFile(entry)) {
+				// Add signature files directly after manifest.
+				entries.add(signatureFileCnt++, entry);
+			} else {
+				// everything else is just at the end in order of the enumeration
+				entries.add(entry);
+			}
+		}
+
+		entryPaths = entries.iterator();
+
+		jarOutput = new JarOutputStream(nextEntryOutput);
+	}
+
+	private boolean isSignatureFile(String entry) {
+		entry = entry.toUpperCase();
+		if (entry.startsWith("META-INF/") && entry.indexOf('/', "META-INF/".length()) == -1) { //$NON-NLS-1$ //$NON-NLS-2$
+			return entry.endsWith(".SF") //$NON-NLS-1$
+					|| entry.endsWith(".DSA") //$NON-NLS-1$
+					|| entry.endsWith(".RSA") //$NON-NLS-1$
+					|| entry.endsWith(".EC"); //$NON-NLS-1$
+		}
+		return false;
+	}
+
+	public int read() throws IOException {
+		if (nextEntryInput != null) {
+			int result = nextEntryInput.read();
+			if (result != -1) {
+				return result;
+			}
+
+			// this entry is done force a new one to be read if there is a next
+			nextEntryInput = null;
+			return read();
+
+		}
+
+		if (entryPaths.hasNext()) {
+			readNext(entryPaths.next());
+
+			if (!entryPaths.hasNext()) {
+				jarOutput.close();
+			}
+		} else {
+			jarOutput.close();
+			return -1;
+		}
+
+		return read();
+	}
+
+	private void readNext(String path) throws IOException {
+		BundleEntry found = bundlefile.getEntry(path);
+		if (found == null) {
+			throw new IOException("No entry found: " + path); //$NON-NLS-1$
+		}
+
+		nextEntryOutput.reset();
+		JarEntry entry = new JarEntry(path);
+		jarOutput.putNextEntry(entry);
+		if (!entry.isDirectory()) {
+			try (InputStream source = found.getInputStream()) {
+				byte[] buf = new byte[8192];
+				int length;
+				while ((length = source.read(buf)) > 0) {
+					jarOutput.write(buf, 0, length);
+				}
+			}
+		}
+
+
+		jarOutput.closeEntry();
+		jarOutput.flush();
+
+		// now save off the entry we just wrote
+		nextEntryInput = new ByteArrayInputStream(nextEntryOutput.toByteArray());
+	}
+
+}