ReceivePack: report protocol parsing failures on channel 3

If the client sent a well-formed enough request to see it wants to use
side-band-64k for status reporting (meaning its a modern client), but
any other command record was somehow invalid (e.g. corrupt SHA-1)
report the parsing exception using channel 3.  This allows clients to
see the failure and know the server will not be continuing.

git-core and JGit clients send all commands and then start a sideband
demux before sending the pack. By consuming all commands first we get
the client into a state where it can see and respond to the channel 3
server failure.

This behavior is useful on HTTPS connections when the client is buggy
and sent a corrupt command, but still managed to request side-band-64k
in the first line.

Change-Id: If385b91ceb9f024ccae2d1645caf15bc6b206130

1 files changed, 40 insertions, 0 deletions

diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/PushConnectionTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/PushConnectionTest.java
index 9e78921b79..33a910505f 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/PushConnectionTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/PushConnectionTest.java
@@ -43,13 +43,18 @@
 
 package org.eclipse.jgit.transport;
 
+import static org.eclipse.jgit.transport.BasePackPushConnection.CAPABILITY_REPORT_STATUS;
+import static org.eclipse.jgit.transport.BasePackPushConnection.CAPABILITY_SIDE_BAND_64K;
 import static org.eclipse.jgit.transport.RemoteRefUpdate.Status.REJECTED_OTHER_REASON;
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.fail;
 
 import java.io.IOException;
+import java.io.StringWriter;
 import java.util.HashMap;
 import java.util.Map;
 
+import org.eclipse.jgit.errors.TransportException;
 import org.eclipse.jgit.internal.storage.dfs.DfsRepositoryDescription;
 import org.eclipse.jgit.internal.storage.dfs.InMemoryRepository;
 import org.eclipse.jgit.lib.Constants;
@@ -133,4 +138,39 @@ public class PushConnectionTest {
 		assertEquals(REJECTED_OTHER_REASON, rru.getStatus());
 		assertEquals("invalid old id sent", rru.getMessage());
 	}
+
+	@Test
+	public void invalidCommand() throws IOException {
+		try (Transport tn = testProtocol.open(uri, client, "server");
+				InternalPushConnection c = (InternalPushConnection) tn.openPush()) {
+			StringWriter msgs = new StringWriter();
+			PacketLineOut pckOut = c.pckOut;
+
+			@SuppressWarnings("resource")
+			SideBandInputStream in = new SideBandInputStream(c.in,
+					NullProgressMonitor.INSTANCE, msgs, null);
+
+			// Explicitly invalid command, but sane enough capabilities.
+			StringBuilder buf = new StringBuilder();
+			buf.append("42");
+			buf.append(' ');
+			buf.append(obj2.name());
+			buf.append(' ');
+			buf.append("refs/heads/A" + obj2.name());
+			buf.append('\0').append(CAPABILITY_SIDE_BAND_64K);
+			buf.append(' ').append(CAPABILITY_REPORT_STATUS);
+			buf.append('\n');
+			pckOut.writeString(buf.toString());
+			pckOut.end();
+
+			try {
+				in.read();
+				fail("expected TransportException");
+			} catch (TransportException e) {
+				assertEquals(
+						"remote: error: invalid protocol: wanted 'old new ref'",
+						e.getMessage());
+			}
+		}
+	}
 }