Validate that end-group tags match their corresponding start-group tags

This detects:
- An end-group tag with the wrong field number (doesn't match the start-group field)
- An end-group tag with no preceding start-group tag

Fixes issue #688.

1 files changed, 48 insertions, 2 deletions

diff --git a/csharp/src/Google.Protobuf.Test/CodedInputStreamTest.cs b/csharp/src/Google.Protobuf.Test/CodedInputStreamTest.cs
index 6ae02112..0e7cf04e 100644
--- a/csharp/src/Google.Protobuf.Test/CodedInputStreamTest.cs
+++ b/csharp/src/Google.Protobuf.Test/CodedInputStreamTest.cs
@@ -470,6 +470,52 @@ namespace Google.Protobuf
         }

 

         [Test]

+        public void SkipGroup_WrongEndGroupTag()

+        {

+            // Create an output stream with:

+            // Field 1: string "field 1"

+            // Start group 2

+            //   Field 3: fixed int32

+            // End group 4 (should give an error)

+            var stream = new MemoryStream();

+            var output = new CodedOutputStream(stream);

+            output.WriteTag(1, WireFormat.WireType.LengthDelimited);

+            output.WriteString("field 1");

+

+            // The outer group...

+            output.WriteTag(2, WireFormat.WireType.StartGroup);

+            output.WriteTag(3, WireFormat.WireType.Fixed32);

+            output.WriteFixed32(100);

+            output.WriteTag(4, WireFormat.WireType.EndGroup);

+            output.Flush();

+            stream.Position = 0;

+

+            // Now act like a generated client

+            var input = new CodedInputStream(stream);

+            Assert.AreEqual(WireFormat.MakeTag(1, WireFormat.WireType.LengthDelimited), input.ReadTag());

+            Assert.AreEqual("field 1", input.ReadString());

+            Assert.AreEqual(WireFormat.MakeTag(2, WireFormat.WireType.StartGroup), input.ReadTag());

+            Assert.Throws<InvalidProtocolBufferException>(input.SkipLastField);

+        }

+

+        [Test]

+        public void RogueEndGroupTag()

+        {

+            // If we have an end-group tag without a leading start-group tag, generated

+            // code will just call SkipLastField... so that should fail.

+

+            var stream = new MemoryStream();

+            var output = new CodedOutputStream(stream);

+            output.WriteTag(1, WireFormat.WireType.EndGroup);

+            output.Flush();

+            stream.Position = 0;

+

+            var input = new CodedInputStream(stream);

+            Assert.AreEqual(WireFormat.MakeTag(1, WireFormat.WireType.EndGroup), input.ReadTag());

+            Assert.Throws<InvalidProtocolBufferException>(input.SkipLastField);

+        }

+

+        [Test]

         public void EndOfStreamReachedWhileSkippingGroup()

         {

             var stream = new MemoryStream();

@@ -484,7 +530,7 @@ namespace Google.Protobuf
             // Now act like a generated client

             var input = new CodedInputStream(stream);

             input.ReadTag();

-            Assert.Throws<InvalidProtocolBufferException>(() => input.SkipLastField());

+            Assert.Throws<InvalidProtocolBufferException>(input.SkipLastField);

         }

 

         [Test]

@@ -506,7 +552,7 @@ namespace Google.Protobuf
             // Now act like a generated client

             var input = new CodedInputStream(stream);

             Assert.AreEqual(WireFormat.MakeTag(1, WireFormat.WireType.StartGroup), input.ReadTag());

-            Assert.Throws<InvalidProtocolBufferException>(() => input.SkipLastField());

+            Assert.Throws<InvalidProtocolBufferException>(input.SkipLastField);

         }

 

         [Test]