diff --git a/proto/decode.go b/proto/decode.go
index bf71dca..8486635 100644
--- a/proto/decode.go
+++ b/proto/decode.go
@@ -46,6 +46,10 @@
 // errOverflow is returned when an integer is too large to be represented.
 var errOverflow = errors.New("proto: integer overflow")
 
+// ErrInternalBadWireType is returned by generated code when an incorrect
+// wire type is encountered. It does not get returned to user code.
+var ErrInternalBadWireType = errors.New("proto: internal error: bad wiretype for oneof")
+
 // The fundamental decoders that interpret bytes on the wire.
 // Those that take integer types all return uint64 and are
 // therefore of type valueDecoder.
@@ -314,6 +318,24 @@
 	return NewBuffer(buf).Unmarshal(pb)
 }
 
+// DecodeMessage reads a count-delimited message from the Buffer.
+func (p *Buffer) DecodeMessage(pb Message) error {
+	enc, err := p.DecodeRawBytes(false)
+	if err != nil {
+		return err
+	}
+	return NewBuffer(enc).Unmarshal(pb)
+}
+
+// DecodeGroup reads a tag-delimited group from the Buffer.
+func (p *Buffer) DecodeGroup(pb Message) error {
+	typ, base, err := getbase(pb)
+	if err != nil {
+		return err
+	}
+	return p.unmarshalType(typ.Elem(), GetProperties(typ.Elem()), true, base)
+}
+
 // Unmarshal parses the protocol buffer representation in the
 // Buffer and places the decoded result in pb.  If the struct
 // underlying pb does not match the data in the buffer, the results can be
@@ -377,6 +399,20 @@
 					continue
 				}
 			}
+			// Maybe it's a oneof?
+			if prop.oneofUnmarshaler != nil {
+				m := structPointer_Interface(base, st).(Message)
+				// First return value indicates whether tag is a oneof field.
+				ok, err = prop.oneofUnmarshaler(m, tag, wire, o)
+				if err == ErrInternalBadWireType {
+					// Map the error to something more descriptive.
+					// Do the formatting here to save generated code space.
+					err = fmt.Errorf("bad wiretype for oneof field in %T", m)
+				}
+				if ok {
+					continue
+				}
+			}
 			err = o.skipAndSave(st, tag, wire, base, prop.unrecField)
 			continue
 		}