Add fuzz test and fix panics found so far

aurp/aurp_test.go

@@ -0,0 +1,25 @@
+/*
+   Copyright 2024 Josh Deprez
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+*/
+
+package aurp
+
+import "testing"
+
+func FuzzParsePacket(f *testing.F) {
+	f.Fuzz(func(t *testing.T, p []byte) {
+		_, _, _ = ParsePacket(p)
+	})
+}

aurp/open.go

@@ -109,12 +109,13 @@ func parseOptionTuple(p []byte) (OptionTuple, []byte, error) {
 		return OptionTuple{}, p, fmt.Errorf("insufficient input length %d for option tuple", len(p))
 	}
 	olen := int(p[0]) + 1
+	p = p[1:]
 	if len(p) < olen {
 		return OptionTuple{}, p, fmt.Errorf("insufficient input for option tuple data length %d", olen)
 	}
 	return OptionTuple{
-		Type: OptionType(p[1]),
+		Type: OptionType(p[0]),
-		Data: p[2:olen],
+		Data: p[1:olen],
 	}, p[olen:], nil
 }
 

aurp/zone_info.go

@@ -65,9 +65,9 @@ func parseZIReqPacket(p []byte) (*ZIReqPacket, error) {
 		return nil, fmt.Errorf("odd number of bytes %d for networks", len(p))
 	}
 	c := len(p) / 2
-	ns := make([]ddp.Network, 0, c)
+	ns := make([]ddp.Network, c)
 	for i := range c {
-		ns[i] = ddp.Network(binary.BigEndian.Uint16(p[i*2:][:2]))
+		ns[i] = ddp.Network(binary.BigEndian.Uint16(p[2*i:][:2]))
 	}
 	return &ZIReqPacket{
 		Subcode:  SubcodeZoneInfoReq,