don't panic on invalid pfx as input

table.go

@@ -55,6 +55,9 @@ func (t *Table[V]) rootNodeByVersion(is4 bool) *node[V] {
 // The prefix must already be normalized!
 func (t *Table[V]) Insert(pfx netip.Prefix, val V) {
 	t.init()
+	if !pfx.IsValid() {
+		return
+	}
 
 	// some values derived from pfx
 	ip, bits, is4 := pfxToValues(pfx)
@@ -110,6 +113,10 @@ func (t *Table[V]) Insert(pfx netip.Prefix, val V) {
 // The prefix must already be normalized!
 func (t *Table[V]) Update(pfx netip.Prefix, cb func(val V, ok bool) V) V {
 	t.init()
+	if !pfx.IsValid() {
+		var zero V
+		return zero
+	}
 
 	// some values derived from pfx
 	ip, bits, is4 := pfxToValues(pfx)
@@ -148,6 +155,9 @@ func (t *Table[V]) Update(pfx netip.Prefix, cb func(val V, ok bool) V) V {
 //
 // The prefix must already be normalized!
 func (t *Table[V]) Get(pfx netip.Prefix) (val V, ok bool) {
+	if !pfx.IsValid() {
+		return
+	}
 	// some values derived from pfx
 	ip, bits, is4 := pfxToValues(pfx)
 
@@ -181,6 +191,9 @@ func (t *Table[V]) Get(pfx netip.Prefix) (val V, ok bool) {
 //
 // The prefix must already be normalized!
 func (t *Table[V]) Delete(pfx netip.Prefix) {
+	if !pfx.IsValid() {
+		return
+	}
 	// some values derived from pfx
 	ip, bits, is4 := pfxToValues(pfx)
 
@@ -243,6 +256,10 @@ func (t *Table[V]) Delete(pfx netip.Prefix) {
 // Lookup does a route lookup (longest prefix match) for IP and
 // returns the associated value and true, or false if no route matched.
 func (t *Table[V]) Lookup(ip netip.Addr) (val V, ok bool) {
+	if !ip.IsValid() {
+		return
+	}
+
 	is4 := ip.Is4()
 
 	n := t.rootNodeByVersion(is4)
@@ -296,6 +313,9 @@ func (t *Table[V]) Lookup(ip netip.Addr) (val V, ok bool) {
 //
 // The prefix must already be normalized!
 func (t *Table[V]) LookupPrefix(pfx netip.Prefix) (val V, ok bool) {
+	if !pfx.IsValid() {
+		return
+	}
 	_, _, val, ok = t.lpmByPrefix(pfx)
 	return
 }
@@ -311,6 +331,9 @@ func (t *Table[V]) LookupPrefix(pfx netip.Prefix) (val V, ok bool) {
 // If LookupPrefixLPM is to be used for IP addresses,
 // they must be converted to /32 or /128 prefixes.
 func (t *Table[V]) LookupPrefixLPM(pfx netip.Prefix) (lpm netip.Prefix, val V, ok bool) {
+	if !pfx.IsValid() {
+		return
+	}
 	depth, baseIdx, val, ok := t.lpmByPrefix(pfx)
 
 	if ok {
@@ -393,6 +416,9 @@ func (t *Table[V]) lpmByPrefix(pfx netip.Prefix) (depth int, baseIdx uint, val V
 //
 // The prefix must already be normalized!
 func (t *Table[V]) Subnets(pfx netip.Prefix) []netip.Prefix {
+	if !pfx.IsValid() {
+		return nil
+	}
 	// some needed values, see below
 	ip, bits, is4 := pfxToValues(pfx)
 
@@ -434,6 +460,9 @@ func (t *Table[V]) Subnets(pfx netip.Prefix) []netip.Prefix {
 //
 // The prefix must already be normalized!
 func (t *Table[V]) Supernets(pfx netip.Prefix) []netip.Prefix {
+	if !pfx.IsValid() {
+		return nil
+	}
 	var result []netip.Prefix
 
 	// some needed values, see below
@@ -477,6 +506,9 @@ func (t *Table[V]) Supernets(pfx netip.Prefix) []netip.Prefix {
 //
 // The prefix must be normalized!
 func (t *Table[V]) OverlapsPrefix(pfx netip.Prefix) bool {
+	if !pfx.IsValid() {
+		return false
+	}
 	// some needed values, see below
 	ip, bits, is4 := pfxToValues(pfx)
 

table_test.go

@@ -31,6 +31,113 @@ var mpp = func(s string) netip.Prefix {
 	return pfx
 }
 
+func TestValid(t *testing.T) {
+	t.Parallel()
+
+	var tbl = new(Table[any])
+	var zero netip.Prefix
+	var testname string
+
+	testname = "Insert"
+	t.Run(testname, func(t *testing.T) {
+		defer func(testname string) {
+			if r := recover(); r != nil {
+				t.Fatalf("%s panics on invalid prefix input", testname)
+			}
+		}(testname)
+
+		tbl.Insert(zero, nil)
+	})
+
+	testname = "Delete"
+	t.Run(testname, func(t *testing.T) {
+		defer func(testname string) {
+			if r := recover(); r != nil {
+				t.Fatalf("%s panics on invalid prefix input", testname)
+			}
+		}(testname)
+
+		tbl.Delete(zero)
+	})
+
+	testname = "Update"
+	t.Run(testname, func(t *testing.T) {
+		defer func(testname string) {
+			if r := recover(); r != nil {
+				t.Fatalf("%s panics on invalid prefix input", testname)
+			}
+		}(testname)
+
+		tbl.Update(zero, func(v any, _ bool) any { return v })
+	})
+
+	testname = "Get"
+	t.Run(testname, func(t *testing.T) {
+		defer func(testname string) {
+			if r := recover(); r != nil {
+				t.Fatalf("%s panics on invalid prefix input", testname)
+			}
+		}(testname)
+
+		tbl.Get(zero)
+	})
+
+	testname = "LookupPrefix"
+	t.Run(testname, func(t *testing.T) {
+		defer func(testname string) {
+			if r := recover(); r != nil {
+				t.Fatalf("%s panics on invalid prefix input", testname)
+			}
+		}(testname)
+
+		tbl.LookupPrefix(zero)
+	})
+
+	testname = "LookupPrefixLPM"
+	t.Run(testname, func(t *testing.T) {
+		defer func(testname string) {
+			if r := recover(); r != nil {
+				t.Fatalf("%s panics on invalid prefix input", testname)
+			}
+		}(testname)
+
+		tbl.LookupPrefixLPM(zero)
+	})
+
+	testname = "Subnets"
+	t.Run(testname, func(t *testing.T) {
+		defer func(testname string) {
+			if r := recover(); r != nil {
+				t.Fatalf("%s panics on invalid prefix input", testname)
+			}
+		}(testname)
+
+		tbl.Subnets(zero)
+	})
+
+	testname = "Supernets"
+	t.Run(testname, func(t *testing.T) {
+		defer func(testname string) {
+			if r := recover(); r != nil {
+				t.Fatalf("%s panics on invalid prefix input", testname)
+			}
+		}(testname)
+
+		tbl.Supernets(zero)
+	})
+
+	testname = "OverlapsPrefix"
+	t.Run(testname, func(t *testing.T) {
+		defer func(testname string) {
+			if r := recover(); r != nil {
+				t.Fatalf("%s panics on invalid prefix input", testname)
+			}
+		}(testname)
+
+		tbl.OverlapsPrefix(zero)
+	})
+}
+
 func TestRegression(t *testing.T) {
 	t.Parallel()
 	// original comment by tailscale for ART,