tailcfg: import ProtoPortRange for local use

Imported type and parsing, with minor modifications.

Updates tailscale/corp#15043

Signed-off-by: James Tucker <james@tailscale.com>

tailcfg/proto_port_range_test.go

@@ -0,0 +1,90 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+package tailcfg
+
+import (
+	"errors"
+	"testing"
+
+	"tailscale.com/types/ipproto"
+)
+
+func TestProtoPortRangeParsing(t *testing.T) {
+	pr := func(s, e uint16) PortRange {
+		return PortRange{First: s, Last: e}
+	}
+	tests := []struct {
+		in  string
+		out ProtoPortRange
+		err error
+	}{
+		{in: "tcp:80", out: ProtoPortRange{Proto: int(ipproto.TCP), Ports: pr(80, 80)}},
+		{in: "80", out: ProtoPortRange{Ports: pr(80, 80)}},
+		{in: "*", out: ProtoPortRange{Ports: PortRangeAny}},
+		{in: "*:*", out: ProtoPortRange{Ports: PortRangeAny}},
+		{in: "tcp:*", out: ProtoPortRange{Proto: int(ipproto.TCP), Ports: PortRangeAny}},
+		{
+			in:  "tcp:",
+			err: errors.New(`invalid port list: ""`),
+		},
+		{
+			in:  ":80",
+			err: errors.New(`empty protocol`),
+		},
+		{
+			in:  "",
+			err: errors.New(`empty string`),
+		},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.in, func(t *testing.T) {
+			ppr, err := parseProtoPortRange(tc.in)
+			if gotErr, wantErr := err != nil, tc.err != nil; gotErr != wantErr {
+				t.Fatalf("got err %v; want %v", err, tc.err)
+			} else if gotErr {
+				if err.Error() != tc.err.Error() {
+					t.Fatalf("got err %q; want %q", err, tc.err)
+				}
+				return
+			}
+			if *ppr != tc.out {
+				t.Fatalf("got %v; want %v", ppr, tc.out)
+			}
+		})
+	}
+}
+
+func TestProtoPortRangeString(t *testing.T) {
+	tests := []struct {
+		input ProtoPortRange
+		want  string
+	}{
+		{ProtoPortRange{}, "0"},
+
+		// Zero protocol.
+		{ProtoPortRange{Ports: PortRangeAny}, "*"},
+		{ProtoPortRange{Ports: PortRange{23, 23}}, "23"},
+		{ProtoPortRange{Ports: PortRange{80, 120}}, "80-120"},
+
+		// Non-zero unnamed protocol.
+		{ProtoPortRange{Proto: 100, Ports: PortRange{80, 80}}, "100:80"},
+		{ProtoPortRange{Proto: 200, Ports: PortRange{101, 105}}, "200:101-105"},
+
+		// Non-zero named protocol.
+		{ProtoPortRange{Proto: 1, Ports: PortRangeAny}, "icmp:*"},
+		{ProtoPortRange{Proto: 2, Ports: PortRangeAny}, "igmp:*"},
+		{ProtoPortRange{Proto: 6, Ports: PortRange{10, 13}}, "tcp:10-13"},
+		{ProtoPortRange{Proto: 17, Ports: PortRangeAny}, "udp:*"},
+		{ProtoPortRange{Proto: 0x84, Ports: PortRange{999, 999}}, "sctp:999"},
+		{ProtoPortRange{Proto: 0x3a, Ports: PortRangeAny}, "ipv6-icmp:*"},
+		{ProtoPortRange{Proto: 0x21, Ports: PortRangeAny}, "dccp:*"},
+		{ProtoPortRange{Proto: 0x2f, Ports: PortRangeAny}, "gre:*"},
+	}
+	for _, tc := range tests {
+		if got := tc.input.String(); got != tc.want {
+			t.Errorf("String for %v: got %q, want %q", tc.input, got, tc.want)
+		}
+	}
+}