Pull request: 3443 dhcp broadcast vol.2

Merge in DNS/adguard-home from 3443-dhcp-broadcast-vol.2 to master Closes #3443. Squashed commit of the following: commit a85af89cb43f2489126fe3c12366fc034e89f59d Merge: 72eb3a88 a4e07827 Author: Eugene Burkov <E.Burkov@AdGuard.COM> Date: Thu Sep 30 18:08:19 2021 +0300 Merge branch 'master' into 3443-dhcp-broadcast-vol.2 commit 72eb3a8853540b06ee1096decf50e836b539fe45 Author: Eugene Burkov <E.Burkov@AdGuard.COM> Date: Thu Sep 30 18:03:19 2021 +0300 dhcpd: imp code readability commit 2d1fbc40d04a4125855d6be9f02e09d15430150d Author: Eugene Burkov <E.Burkov@AdGuard.COM> Date: Thu Sep 30 14:16:59 2021 +0300 dhcpd: imp tests commit 889fad3084ad2b81edfc12100e2ce29d323227ba Author: Eugene Burkov <E.Burkov@AdGuard.COM> Date: Wed Sep 29 20:09:25 2021 +0300 dhcpd: imp code, docs commit 1fd6b2346ff66e033bceaa169aed751be5822ca8 Author: Eugene Burkov <E.Burkov@AdGuard.COM> Date: Thu Sep 23 16:08:18 2021 +0300 dhcpd: unicast to mac address
2021-09-30 18:28:19 +03:00
parent a4e078271c
commit da86620288
12 changed files with 531 additions and 231 deletions
--- a/internal/dhcpd/conn_unix_test.go
+++ b/internal/dhcpd/conn_unix_test.go
@@ -0,0 +1,114 @@
+//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris
+// +build aix darwin dragonfly freebsd linux netbsd openbsd solaris
+
+package dhcpd
+
+import (
+	"net"
+	"strings"
+	"testing"
+
+	"github.com/google/gopacket"
+	"github.com/google/gopacket/layers"
+	"github.com/insomniacslk/dhcp/dhcpv4"
+	"github.com/mdlayher/raw"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestDHCPConn_WriteTo_common(t *testing.T) {
+	respData := (&dhcpv4.DHCPv4{}).ToBytes()
+	udpAddr := &net.UDPAddr{
+		IP:   net.IP{1, 2, 3, 4},
+		Port: dhcpv4.ClientPort,
+	}
+
+	t.Run("unicast_ip", func(t *testing.T) {
+		writeTo := func(_ []byte, addr net.Addr) (_ int, _ error) {
+			assert.Equal(t, udpAddr, addr)
+
+			return 0, nil
+		}
+
+		conn := &dhcpConn{udpConn: &fakePacketConn{writeTo: writeTo}}
+
+		_, err := conn.WriteTo(respData, udpAddr)
+		assert.NoError(t, err)
+	})
+
+	t.Run("unexpected_addr_type", func(t *testing.T) {
+		type unexpectedAddrType struct {
+			net.Addr
+		}
+
+		conn := &dhcpConn{}
+		n, err := conn.WriteTo(nil, &unexpectedAddrType{})
+		require.Error(t, err)
+
+		assert.True(t, strings.Contains(err.Error(), "peer is of unexpected type"))
+		assert.Zero(t, n)
+	})
+}
+
+func TestBuildEtherPkt(t *testing.T) {
+	conn := &dhcpConn{
+		srcMAC: net.HardwareAddr{1, 2, 3, 4, 5, 6},
+		srcIP:  net.IP{1, 2, 3, 4},
+	}
+	peer := &dhcpUnicastAddr{
+		Addr:   raw.Addr{HardwareAddr: net.HardwareAddr{6, 5, 4, 3, 2, 1}},
+		yiaddr: net.IP{4, 3, 2, 1},
+	}
+	payload := (&dhcpv4.DHCPv4{}).ToBytes()
+
+	t.Run("success", func(t *testing.T) {
+		pkt, err := conn.buildEtherPkt(payload, peer)
+		require.NoError(t, err)
+
+		assert.NotEmpty(t, pkt)
+
+		actualPkt := gopacket.NewPacket(pkt, layers.LayerTypeEthernet, gopacket.DecodeOptions{
+			NoCopy: true,
+		})
+		require.NotNil(t, actualPkt)
+
+		wantTypes := []gopacket.LayerType{
+			layers.LayerTypeEthernet,
+			layers.LayerTypeIPv4,
+			layers.LayerTypeUDP,
+			layers.LayerTypeDHCPv4,
+		}
+		actualLayers := actualPkt.Layers()
+		require.Len(t, actualLayers, len(wantTypes))
+
+		for i, wantType := range wantTypes {
+			layer := actualLayers[i]
+			require.NotNil(t, layer)
+
+			assert.Equal(t, wantType, layer.LayerType())
+		}
+	})
+
+	t.Run("non-serializable", func(t *testing.T) {
+		// Create an invalid DHCP packet.
+		invalidPayload := []byte{1, 2, 3, 4}
+		pkt, err := conn.buildEtherPkt(invalidPayload, nil)
+		require.Error(t, err)
+
+		assert.ErrorIs(t, err, errInvalidPktDHCP)
+		assert.Empty(t, pkt)
+	})
+
+	t.Run("serializing_error", func(t *testing.T) {
+		// Create a peer with invalid MAC.
+		badPeer := &dhcpUnicastAddr{
+			Addr:   raw.Addr{HardwareAddr: net.HardwareAddr{5, 4, 3, 2, 1}},
+			yiaddr: net.IP{4, 3, 2, 1},
+		}
+
+		pkt, err := conn.buildEtherPkt(payload, badPeer)
+		require.Error(t, err)
+
+		assert.Empty(t, pkt)
+	})
+}