dhcpv4: better tests

heyxkhoa · Oct 18, 2021 · 720b896 · 720b896
1 parent 1098bef
commit 720b896
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Showing 2 changed files with 45 additions and 33 deletions.
diff --git a/internal/dhcpd/dhcpd_test.go b/internal/dhcpd/dhcpd_test.go
@@ -141,44 +141,51 @@ func TestNormalizeLeases(t *testing.T) {
 func TestV4SubnetRange(t *testing.T) {
 	var err error
 
-	_, err = v4Create(V4ServerConf{
+	baseConf := V4ServerConf{
 		Enabled:    true,
 		RangeStart: net.IP{192, 168, 10, 100},
 		RangeEnd:   net.IP{192, 168, 10, 200},
 		GatewayIP:  net.IP{192, 168, 10, 1},
-		SubnetMask: net.IP{255, 255, 255, 240},
-		notify:     testNotify,
-	})
-	require.Error(t, err)
-
-	_, err = v4Create(V4ServerConf{
-		Enabled:    true,
-		RangeStart: net.IP{192, 168, 10, 222},
-		RangeEnd:   net.IP{192, 168, 10, 111},
-		GatewayIP:  net.IP{192, 168, 10, 1},
 		SubnetMask: net.IP{255, 255, 255, 0},
 		notify:     testNotify,
-	})
-	require.Error(t, err)
+	}
 
-	_, err = v4Create(V4ServerConf{
-		Enabled:    true,
-		RangeStart: net.IP{192, 168, 10, 111},
-		RangeEnd:   net.IP{192, 168, 10, 222},
-		GatewayIP:  net.IP{192, 168, 10, 199},
-		SubnetMask: net.IP{255, 255, 255, 0},
-		notify:     testNotify,
-	})
-	require.Error(t, err)
+	testCases := []struct {
+		name      string
+		lastBytes []byte
+		want      error
+	}{{
+		name: "outside range",
+		lastBytes: []byte{
+			100, 200, 1, 240,
+		},
+		want: errBadRange,
+	}, {
+		name: "outside range end",
+		lastBytes: []byte{
+			5, 200, 1, 240,
+		},
+		want: errBadRange,
+	}, {
+		name: "gateway in range",
+		lastBytes: []byte{
+			111, 222, 199, 0,
+		},
+		want: errBadRange,
+	}}
 
-	_, err = v4Create(V4ServerConf{
-		Enabled:    true,
-		RangeStart: net.IP{192, 168, 10, 111},
-		GatewayIP:  net.IP{192, 168, 10, 199},
-		SubnetMask: net.IP{255, 255, 255, 0},
-		notify:     testNotify,
-	})
-	require.Error(t, err)
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			conf := baseConf
+			conf.RangeStart[3] = tc.lastBytes[0]
+			conf.RangeEnd[3] = tc.lastBytes[1]
+			conf.GatewayIP[3] = tc.lastBytes[2]
+			conf.SubnetMask[3] = tc.lastBytes[3]
+
+			_, err = v4Create(conf)
+			assert.ErrorIs(t, err, tc.want)
+		})
+	}
 }
 
 // cloneUDPAddr returns a deep copy of a.

diff --git a/internal/dhcpd/v4.go b/internal/dhcpd/v4.go
@@ -56,6 +56,8 @@ func (s *v4Server) WriteDiskConfig4(c *V4ServerConf) {
 func (s *v4Server) WriteDiskConfig6(c *V6ServerConf) {
 }
 
+const errBadRange errors.Error = "bad range"
+
 // normalizeHostname normalizes a hostname sent by the client.  If err is not
 // nil, norm is an empty string.
 func normalizeHostname(hostname string) (norm string, err error) {
@@ -1127,24 +1129,27 @@ func v4Create(conf V4ServerConf) (srv DHCPServer, err error) {
 	}
 
 	if s.conf.ipRange.contains(routerIP) {
-		return s, fmt.Errorf("dhcpv4: gateway ip %v in the ip range: %v-%v",
+		return s, fmt.Errorf("dhcpv4: gateway ip %v in the ip range: %v-%v: %w",
 			routerIP,
 			conf.RangeStart,
 			conf.RangeEnd,
+			errBadRange,
 		)
 	}
 
 	if !s.conf.subnet.Contains(conf.RangeStart) {
-		return s, fmt.Errorf("dhcpv4: range start %v is outside network: %v",
+		return s, fmt.Errorf("dhcpv4: range start %v is outside network: %v: %w",
 			conf.RangeStart,
 			s.conf.subnet,
+			errBadRange,
 		)
 	}
 
 	if !s.conf.subnet.Contains(conf.RangeEnd) {
-		return s, fmt.Errorf("dhcpv4: range end %v is outside network: %v",
+		return s, fmt.Errorf("dhcpv4: range end %v is outside network: %v: %w",
 			conf.RangeEnd,
 			s.conf.subnet,
+			errBadRange,
 		)
 	}