HttpSupport.proxyFor(): use only scheme, host, and port

Some URLs cannot be converted via URL.toURI(). So don't convert
the full URL but only the bits that are needed to find a proxy
via java.net.ProxySelector.

Bug: 549690
Change-Id: I55b5ecee70c6b52f72f9bdba9ce552fde7f33976
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

org.eclipse.jgit.test/tst/org/eclipse/jgit/util/HttpSupportTest.java

@@ -0,0 +1,69 @@
+/*
+ * Copyright (c) 2019, Thomas Wolf <thomas.wolf@paranor.ch> and others
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Distribution License v. 1.0 which is available at
+ * http://www.eclipse.org/org/documents/edl-v10.php.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+package org.eclipse.jgit.util;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
+
+import java.io.IOException;
+import java.net.InetSocketAddress;
+import java.net.Proxy;
+import java.net.ProxySelector;
+import java.net.SocketAddress;
+import java.net.URI;
+import java.net.URL;
+import java.util.Collections;
+import java.util.List;
+
+import org.junit.Test;
+
+public class HttpSupportTest {
+
+	private static class TestProxySelector extends ProxySelector {
+
+		private static final Proxy DUMMY = new Proxy(Proxy.Type.HTTP,
+				InetSocketAddress.createUnresolved("localhost", 0));
+
+		@Override
+		public List<Proxy> select(URI uri) {
+			if ("http".equals(uri.getScheme())
+					&& "somehost".equals(uri.getHost())) {
+				return Collections.singletonList(DUMMY);
+			}
+			return Collections.singletonList(Proxy.NO_PROXY);
+		}
+
+		@Override
+		public void connectFailed(URI uri, SocketAddress sa, IOException ioe) {
+			// Empty
+		}
+	}
+
+	@Test
+	public void testMalformedUri() throws Exception {
+		// Valid URL, but backslash is not allowed in a URI in the userinfo part
+		// per RFC 3986: https://tools.ietf.org/html/rfc3986#section-3.2.1 .
+		// Test that conversion to URI to call the ProxySelector does not throw
+		// an exception.
+		Proxy proxy = HttpSupport.proxyFor(new TestProxySelector(), new URL(
+				"http://infor\\c.jones@somehost/somewhere/someproject.git"));
+		assertNotNull(proxy);
+		assertEquals(Proxy.Type.HTTP, proxy.type());
+	}
+
+	@Test
+	public void testCorrectUri() throws Exception {
+		// Backslash escaped as %5C is correct.
+		Proxy proxy = HttpSupport.proxyFor(new TestProxySelector(), new URL(
+				"http://infor%5Cc.jones@somehost/somewhere/someproject.git"));
+		assertNotNull(proxy);
+		assertEquals(Proxy.Type.HTTP, proxy.type());
+	}
+}

org.eclipse.jgit/src/org/eclipse/jgit/util/HttpSupport.java

@@ -51,6 +51,7 @@ import java.io.UnsupportedEncodingException;
 import java.net.ConnectException;
 import java.net.Proxy;
 import java.net.ProxySelector;
+import java.net.URI;
 import java.net.URISyntaxException;
 import java.net.URL;
 import java.net.URLEncoder;
@@ -299,7 +300,9 @@ public class HttpSupport {
 	public static Proxy proxyFor(ProxySelector proxySelector, URL u)
 			throws ConnectException {
 		try {
-			return proxySelector.select(u.toURI()).get(0);
+			URI uri = new URI(u.getProtocol(), null, u.getHost(), u.getPort(),
+					null, null, null);
+			return proxySelector.select(uri).get(0);
 		} catch (URISyntaxException e) {
 			final ConnectException err;
 			err = new ConnectException(MessageFormat.format(JGitText.get().cannotDetermineProxyFor, u));