tsweb: add more test cases for TestCleanRedirectURL (#11331)

Updates #cleanup

Signed-off-by: Chris Palmer <cpalmer@tailscale.com>

tsweb/tsweb_test.go

@@ -637,7 +637,6 @@ func TestCleanRedirectURL(t *testing.T) {
 		{"https://tailscale.com/foo", tailscaleHost, "https://tailscale.com/foo", false},
 		{"/foo", tailscaleHost, "/foo", false},
 		{"//tailscale.com/foo", tailscaleHost, "//tailscale.com/foo", false},
-
 		{"/a/foobar", tailscaleHost, "/a/foobar", false},
 		{"http://127.0.0.1/a/foobar", localHost, "http://127.0.0.1/a/foobar", false},
 		{"http://127.0.0.1:123/a/foobar", localHost, "http://127.0.0.1:123/a/foobar", false},
@@ -650,6 +649,15 @@ func TestCleanRedirectURL(t *testing.T) {
 		{"http://myserver:31544/a/foobar", myServer, "http://myserver:31544/a/foobar", false},
 		{"http://evil.com/foo", tailscaleHost, "", true},
 		{"//evil.com", tailscaleHost, "", true},
+		{"\\\\evil.com", tailscaleHost, "", true},
+		{"javascript:alert(123)", tailscaleHost, "", true},
+		{"file:///", tailscaleHost, "", true},
+		{"file:////SERVER/directory/goats.txt", tailscaleHost, "", true},
+		{"https://google.com", tailscaleHost, "", true},
+		{"", tailscaleHost, "", false},
+		{"\"\"", tailscaleHost, "", true},
+		{"https://tailscale.com@goats.com:8443", tailscaleHost, "", true},
+		{"https://tailscale.com:8443@goats.com:8443", tailscaleHost, "", true},
 		{"HttP://tailscale.com", tailscaleHost, "http://tailscale.com", false},
 		{"http://TaIlScAlE.CoM/spongebob", tailscaleHost, "http://TaIlScAlE.CoM/spongebob", false},
 		{"ftp://tailscale.com", tailscaleHost, "", true},