policy: more reduce route test

Signed-off-by: Kristoffer Dalby <kristoffer@tailscale.com>

hscontrol/policy/policy_test.go

@@ -1,6 +1,7 @@
 package policy
 
 import (
+	"encoding/json"
 	"fmt"
 	"net/netip"
 	"testing"
@@ -16,6 +17,7 @@ import (
 	"gorm.io/gorm"
 	"tailscale.com/net/tsaddr"
 	"tailscale.com/tailcfg"
+	"tailscale.com/util/must"
 )
 
 var ap = func(ipStr string) *netip.Addr {
@@ -23,6 +25,11 @@ var ap = func(ipStr string) *netip.Addr {
 	return &ip
 }
 
+var p = func(prefStr string) netip.Prefix {
+	ip := netip.MustParsePrefix(prefStr)
+	return ip
+}
+
 // hsExitNodeDestForTest is the list of destination IP ranges that are allowed when
 // we use headscale "autogroup:internet".
 var hsExitNodeDestForTest = []tailcfg.NetPortRange{
@@ -762,6 +769,54 @@ func TestReduceFilterRules(t *testing.T) {
 				},
 			},
 		},
+		{
+			name: "2365-only-route-policy",
+			pol: `
+{
+  "hosts": {
+    "router": "100.64.0.1/32",
+    "node": "100.64.0.2/32"
+  },
+  "acls": [
+    {
+      "action": "accept",
+      "src": [
+        "*"
+      ],
+      "dst": [
+        "router:8000"
+      ]
+    },
+    {
+      "action": "accept",
+      "src": [
+        "node"
+      ],
+      "dst": [
+        "172.26.0.0/16:*"
+      ]
+    }
+  ],
+}
+`,
+			node: &types.Node{
+				IPv4: ap("100.64.0.2"),
+				IPv6: ap("fd7a:115c:a1e0::2"),
+				User: users[3],
+			},
+			peers: types.Nodes{
+				&types.Node{
+					IPv4: ap("100.64.0.1"),
+					IPv6: ap("fd7a:115c:a1e0::1"),
+					User: users[1],
+					Hostinfo: &tailcfg.Hostinfo{
+						RoutableIPs: []netip.Prefix{p("172.16.0.0/24"), p("10.10.11.0/24"), p("10.10.12.0/24")},
+					},
+					ApprovedRoutes: []netip.Prefix{p("172.16.0.0/24"), p("10.10.11.0/24"), p("10.10.12.0/24")},
+				},
+			},
+			want: []tailcfg.FilterRule{},
+		},
 	}
 
 	for _, tt := range tests {
@@ -773,6 +828,7 @@ func TestReduceFilterRules(t *testing.T) {
 				pm, err = pmf(users, append(tt.peers, tt.node))
 				require.NoError(t, err)
 				got, _ := pm.Filter()
+				t.Logf("full filter:\n%s", must.Get(json.MarshalIndent(got, "", "  ")))
 				got = ReduceFilterRules(tt.node, got)
 
 				if diff := cmp.Diff(tt.want, got); diff != "" {