Pull request: 2846 cover aghnet vol.1

Merge in DNS/adguard-home from 2846-cover-aghnet-vol.1 to master

Updates #2846.

Squashed commit of the following:

commit 368e75b0bacb290f9929b8a5a682b06f2d75df6a
Author: Eugene Burkov <E.Burkov@AdGuard.COM>
Date:   Fri Jan 21 19:11:59 2022 +0300

    aghnet: imp tests

commit 8bb3e2a1680fd30294f7c82693891ffb19474c6a
Author: Eugene Burkov <E.Burkov@AdGuard.COM>
Date:   Fri Jan 21 18:27:06 2022 +0300

    aghnet: rm unused test

commit 28d8e64880f845810d0af629e5d1f06b9bde5b28
Author: Eugene Burkov <E.Burkov@AdGuard.COM>
Date:   Fri Jan 21 18:18:22 2022 +0300

    aghnet: cover with tests

internal/aghnet/dhcp_unix.go

@@ -19,7 +19,8 @@ import (
 	"github.com/insomniacslk/dhcp/iana"
 )
 
-// defaultDiscoverTime is the
+// defaultDiscoverTime is the default timeout of checking another DHCP server
+// response.
 const defaultDiscoverTime = 3 * time.Second
 
 func checkOtherDHCP(ifaceName string) (ok4, ok6 bool, err4, err6 error) {

internal/aghnet/hostscontainer_test.go

@@ -343,113 +343,93 @@ func TestHostsContainer(t *testing.T) {
 
 	testdata := os.DirFS("./testdata")
 
-	nRewrites := func(t *testing.T, res *urlfilter.DNSResult, n int) (rws []*rules.DNSRewrite) {
-		rewrites := res.DNSRewrites()
-		require.Len(t, rewrites, n)
-
-		for _, rewrite := range rewrites {
-			require.Equal(t, listID, rewrite.FilterListID)
-
-			rw := rewrite.DNSRewrite
-			require.NotNil(t, rw)
-
-			rws = append(rws, rw)
-		}
-
-		return rws
-	}
-
 	testCases := []struct {
-		testTail func(t *testing.T, res *urlfilter.DNSResult)
+		want []*rules.DNSRewrite
-		name     string
+		name string
-		req      urlfilter.DNSRequest
+		req  urlfilter.DNSRequest
 	}{{
+		want: []*rules.DNSRewrite{{
+			RCode:  dns.RcodeSuccess,
+			Value:  net.IPv4(1, 0, 0, 1),
+			RRType: dns.TypeA,
+		}, {
+			RCode:  dns.RcodeSuccess,
+			Value:  net.IP(append((&[15]byte{})[:], byte(1))),
+			RRType: dns.TypeAAAA,
+		}},
 		name: "simple",
 		req: urlfilter.DNSRequest{
 			Hostname: "simplehost",
 			DNSType:  dns.TypeA,
 		},
-		testTail: func(t *testing.T, res *urlfilter.DNSResult) {
-			rws := nRewrites(t, res, 2)
-
-			v, ok := rws[0].Value.(net.IP)
-			require.True(t, ok)
-
-			assert.True(t, net.IP{1, 0, 0, 1}.Equal(v))
-
-			v, ok = rws[1].Value.(net.IP)
-			require.True(t, ok)
-
-			// It's ::1.
-			assert.True(t, net.IP(append((&[15]byte{})[:], byte(1))).Equal(v))
-		},
 	}, {
+		want: []*rules.DNSRewrite{{
+			RCode:    dns.RcodeSuccess,
+			NewCNAME: "hello",
+		}},
 		name: "hello_alias",
 		req: urlfilter.DNSRequest{
 			Hostname: "hello.world",
 			DNSType:  dns.TypeA,
 		},
-		testTail: func(t *testing.T, res *urlfilter.DNSResult) {
-			assert.Equal(t, "hello", nRewrites(t, res, 1)[0].NewCNAME)
-		},
 	}, {
+		want: []*rules.DNSRewrite{{
+			RCode:    dns.RcodeSuccess,
+			NewCNAME: "hello",
+		}},
 		name: "other_line_alias",
 		req: urlfilter.DNSRequest{
 			Hostname: "hello.world.again",
 			DNSType:  dns.TypeA,
 		},
-		testTail: func(t *testing.T, res *urlfilter.DNSResult) {
-			assert.Equal(t, "hello", nRewrites(t, res, 1)[0].NewCNAME)
-		},
 	}, {
+		want: []*rules.DNSRewrite{},
 		name: "hello_subdomain",
 		req: urlfilter.DNSRequest{
 			Hostname: "say.hello",
 			DNSType:  dns.TypeA,
 		},
-		testTail: func(t *testing.T, res *urlfilter.DNSResult) {
-			assert.Empty(t, res.DNSRewrites())
-		},
 	}, {
+		want: []*rules.DNSRewrite{},
 		name: "hello_alias_subdomain",
 		req: urlfilter.DNSRequest{
 			Hostname: "say.hello.world",
 			DNSType:  dns.TypeA,
 		},
-		testTail: func(t *testing.T, res *urlfilter.DNSResult) {
-			assert.Empty(t, res.DNSRewrites())
-		},
 	}, {
+		want: []*rules.DNSRewrite{{
+			RCode:    dns.RcodeSuccess,
+			NewCNAME: "a.whole",
+		}},
 		name: "lots_of_aliases",
 		req: urlfilter.DNSRequest{
 			Hostname: "for.testing",
 			DNSType:  dns.TypeA,
 		},
-		testTail: func(t *testing.T, res *urlfilter.DNSResult) {
-			assert.Equal(t, "a.whole", nRewrites(t, res, 1)[0].NewCNAME)
-		},
 	}, {
+		want: []*rules.DNSRewrite{{
+			RCode:  dns.RcodeSuccess,
+			RRType: dns.TypePTR,
+			Value:  "simplehost.",
+		}},
 		name: "reverse",
 		req: urlfilter.DNSRequest{
 			Hostname: "1.0.0.1.in-addr.arpa",
 			DNSType:  dns.TypePTR,
 		},
-		testTail: func(t *testing.T, res *urlfilter.DNSResult) {
-			rws := nRewrites(t, res, 1)
-
-			assert.Equal(t, dns.TypePTR, rws[0].RRType)
-			assert.Equal(t, "simplehost.", rws[0].Value)
-		},
 	}, {
+		want: []*rules.DNSRewrite{},
 		name: "non-existing",
 		req: urlfilter.DNSRequest{
 			Hostname: "nonexisting",
 			DNSType:  dns.TypeA,
 		},
-		testTail: func(t *testing.T, res *urlfilter.DNSResult) {
+	}, {
-			require.NotNil(t, res)
+		want: nil,
-
+		name: "bad_type",
-			assert.Nil(t, res.DNSRewrites())
+		req: urlfilter.DNSRequest{
+			Hostname: "1.0.0.1.in-addr.arpa",
+			DNSType:  dns.TypeSRV,
 		},
 	}}
 
@@ -466,9 +446,26 @@ func TestHostsContainer(t *testing.T) {
 		t.Run(tc.name, func(t *testing.T) {
 			res, ok := hc.MatchRequest(tc.req)
 			require.False(t, ok)
+
+			if tc.want == nil {
+				assert.Nil(t, res)
+
+				return
+			}
+
 			require.NotNil(t, res)
 
-			tc.testTail(t, res)
+			rewrites := res.DNSRewrites()
+			require.Len(t, rewrites, len(tc.want))
+
+			for i, rewrite := range rewrites {
+				require.Equal(t, listID, rewrite.FilterListID)
+
+				rw := rewrite.DNSRewrite
+				require.NotNil(t, rw)
+
+				assert.Equal(t, tc.want[i], rw)
+			}
 		})
 	}
 }

internal/aghnet/interfaces.go

@@ -25,6 +25,13 @@ type NetIface interface {
 
 // IfaceIPAddrs returns the interface's IP addresses.
 func IfaceIPAddrs(iface NetIface, ipv IPVersion) (ips []net.IP, err error) {
+	switch ipv {
+	case IPVersion4, IPVersion6:
+		// Go on.
+	default:
+		return nil, fmt.Errorf("invalid ip version %d", ipv)
+	}
+
 	addrs, err := iface.Addrs()
 	if err != nil {
 		return nil, err
@@ -41,20 +48,16 @@ func IfaceIPAddrs(iface NetIface, ipv IPVersion) (ips []net.IP, err error) {
 			continue
 		}
 
-		// Assume that net.(*Interface).Addrs can only return valid IPv4
+		// Assume that net.(*Interface).Addrs can only return valid IPv4 and
-		// and IPv6 addresses.  Thus, if it isn't an IPv4 address, it
+		// IPv6 addresses.  Thus, if it isn't an IPv4 address, it must be an
-		// must be an IPv6 one.
+		// IPv6 one.
-		switch ipv {
+		ip4 := ip.To4()
-		case IPVersion4:
+		if ipv == IPVersion4 {
-			if ip4 := ip.To4(); ip4 != nil {
+			if ip4 != nil {
 				ips = append(ips, ip4)
 			}
-		case IPVersion6:
+		} else if ip4 == nil {
-			if ip6 := ip.To4(); ip6 == nil {
+			ips = append(ips, ip)
-				ips = append(ips, ip)
-			}
-		default:
-			return nil, fmt.Errorf("invalid ip version %d", ipv)
 		}
 	}
 
@@ -96,16 +99,16 @@ func IfaceDNSIPAddrs(
 
 	switch len(addrs) {
 	case 0:
-		// Don't return errors in case the users want to try and enable
+		// Don't return errors in case the users want to try and enable the DHCP
-		// the DHCP server later.
+		// server later.
 		t := time.Duration(n) * backoff
 		log.Error("dhcpv%d: no ip for iface after %d attempts and %s", ipv, n, t)
 
 		return nil, nil
 	case 1:
-		// Some Android devices use 8.8.8.8 if there is not a secondary
+		// Some Android devices use 8.8.8.8 if there is not a secondary DNS
-		// DNS server.  Fix that by setting the secondary DNS address to
+		// server.  Fix that by setting the secondary DNS address to the same
-		// the same address.
+		// address.
 		//
 		// See https://github.com/AdguardTeam/AdGuardHome/issues/1708.
 		log.Debug("dhcpv%d: setting secondary dns ip to itself", ipv)

internal/aghnet/interfaces_test.go

@@ -5,13 +5,15 @@ import (
 	"testing"
 
 	"github.com/AdguardTeam/golibs/errors"
+	"github.com/AdguardTeam/golibs/testutil"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 )
 
+// fakeIface is a stub implementation of aghnet.NetIface to simplify testing.
 type fakeIface struct {
-	addrs []net.Addr
 	err   error
+	addrs []net.Addr
 }
 
 // Addrs implements the NetIface interface for *fakeIface.
@@ -33,61 +35,86 @@ func TestIfaceIPAddrs(t *testing.T) {
 	addr6 := &net.IPNet{IP: ip6}
 
 	testCases := []struct {
-		name    string
+		iface      NetIface
-		iface   NetIface
+		name       string
-		ipv     IPVersion
+		wantErrMsg string
-		want    []net.IP
+		want       []net.IP
-		wantErr error
+		ipv        IPVersion
 	}{{
-		name:    "ipv4_success",
+		iface:      &fakeIface{addrs: []net.Addr{addr4}, err: nil},
-		iface:   &fakeIface{addrs: []net.Addr{addr4}, err: nil},
+		name:       "ipv4_success",
-		ipv:     IPVersion4,
+		wantErrMsg: "",
-		want:    []net.IP{ip4},
+		want:       []net.IP{ip4},
-		wantErr: nil,
+		ipv:        IPVersion4,
 	}, {
-		name:    "ipv4_success_with_ipv6",
+		iface:      &fakeIface{addrs: []net.Addr{addr6, addr4}, err: nil},
-		iface:   &fakeIface{addrs: []net.Addr{addr6, addr4}, err: nil},
+		name:       "ipv4_success_with_ipv6",
-		ipv:     IPVersion4,
+		wantErrMsg: "",
-		want:    []net.IP{ip4},
+		want:       []net.IP{ip4},
-		wantErr: nil,
+		ipv:        IPVersion4,
 	}, {
-		name:    "ipv4_error",
+		iface:      &fakeIface{addrs: []net.Addr{addr4}, err: errTest},
-		iface:   &fakeIface{addrs: []net.Addr{addr4}, err: errTest},
+		name:       "ipv4_error",
-		ipv:     IPVersion4,
+		wantErrMsg: errTest.Error(),
-		want:    nil,
+		want:       nil,
-		wantErr: errTest,
+		ipv:        IPVersion4,
 	}, {
-		name:    "ipv6_success",
+		iface:      &fakeIface{addrs: []net.Addr{addr6}, err: nil},
-		iface:   &fakeIface{addrs: []net.Addr{addr6}, err: nil},
+		name:       "ipv6_success",
-		ipv:     IPVersion6,
+		wantErrMsg: "",
-		want:    []net.IP{ip6},
+		want:       []net.IP{ip6},
-		wantErr: nil,
+		ipv:        IPVersion6,
 	}, {
-		name:    "ipv6_success_with_ipv4",
+		iface:      &fakeIface{addrs: []net.Addr{addr6, addr4}, err: nil},
-		iface:   &fakeIface{addrs: []net.Addr{addr6, addr4}, err: nil},
+		name:       "ipv6_success_with_ipv4",
-		ipv:     IPVersion6,
+		wantErrMsg: "",
-		want:    []net.IP{ip6},
+		want:       []net.IP{ip6},
-		wantErr: nil,
+		ipv:        IPVersion6,
 	}, {
-		name:    "ipv6_error",
+		iface:      &fakeIface{addrs: []net.Addr{addr6}, err: errTest},
-		iface:   &fakeIface{addrs: []net.Addr{addr6}, err: errTest},
+		name:       "ipv6_error",
-		ipv:     IPVersion6,
+		wantErrMsg: errTest.Error(),
-		want:    nil,
+		want:       nil,
-		wantErr: errTest,
+		ipv:        IPVersion6,
+	}, {
+		iface:      &fakeIface{addrs: nil, err: nil},
+		name:       "bad_proto",
+		wantErrMsg: "invalid ip version 10",
+		want:       nil,
+		ipv:        IPVersion6 + IPVersion4,
+	}, {
+		iface:      &fakeIface{addrs: []net.Addr{&net.IPAddr{IP: ip4}}, err: nil},
+		name:       "ipaddr_v4",
+		wantErrMsg: "",
+		want:       []net.IP{ip4},
+		ipv:        IPVersion4,
+	}, {
+		iface:      &fakeIface{addrs: []net.Addr{&net.IPAddr{IP: ip6, Zone: ""}}, err: nil},
+		name:       "ipaddr_v6",
+		wantErrMsg: "",
+		want:       []net.IP{ip6},
+		ipv:        IPVersion6,
+	}, {
+		iface:      &fakeIface{addrs: []net.Addr{&net.UnixAddr{}}, err: nil},
+		name:       "non-ipv4",
+		wantErrMsg: "",
+		want:       nil,
+		ipv:        IPVersion4,
 	}}
 
 	for _, tc := range testCases {
 		t.Run(tc.name, func(t *testing.T) {
-			got, gotErr := IfaceIPAddrs(tc.iface, tc.ipv)
+			got, err := IfaceIPAddrs(tc.iface, tc.ipv)
-			require.True(t, errors.Is(gotErr, tc.wantErr))
+			testutil.AssertErrorMsg(t, tc.wantErrMsg, err)
+
 			assert.Equal(t, tc.want, got)
 		})
 	}
 }
 
 type waitingFakeIface struct {
-	addrs []net.Addr
 	err   error
+	addrs []net.Addr
 	n     int
 }
 
@@ -116,11 +143,11 @@ func TestIfaceDNSIPAddrs(t *testing.T) {
 	addr6 := &net.IPNet{IP: ip6}
 
 	testCases := []struct {
-		name    string
 		iface   NetIface
-		ipv     IPVersion
-		want    []net.IP
 		wantErr error
+		name    string
+		want    []net.IP
+		ipv     IPVersion
 	}{{
 		name:    "ipv4_success",
 		iface:   &fakeIface{addrs: []net.Addr{addr4}, err: nil},
@@ -169,12 +196,25 @@ func TestIfaceDNSIPAddrs(t *testing.T) {
 		ipv:     IPVersion6,
 		want:    []net.IP{ip6, ip6},
 		wantErr: nil,
+	}, {
+		name:    "empty",
+		iface:   &fakeIface{addrs: nil, err: nil},
+		ipv:     IPVersion4,
+		want:    nil,
+		wantErr: nil,
+	}, {
+		name:    "many",
+		iface:   &fakeIface{addrs: []net.Addr{addr4, addr4}},
+		ipv:     IPVersion4,
+		want:    []net.IP{ip4, ip4},
+		wantErr: nil,
 	}}
 
 	for _, tc := range testCases {
 		t.Run(tc.name, func(t *testing.T) {
-			got, gotErr := IfaceDNSIPAddrs(tc.iface, tc.ipv, 2, 0)
+			got, err := IfaceDNSIPAddrs(tc.iface, tc.ipv, 2, 0)
-			require.True(t, errors.Is(gotErr, tc.wantErr))
+			require.ErrorIs(t, err, tc.wantErr)
+
 			assert.Equal(t, tc.want, got)
 		})
 	}

internal/aghnet/ipmut_test.go

@@ -0,0 +1,44 @@
+package aghnet
+
+import (
+	"net"
+	"testing"
+
+	"github.com/AdguardTeam/golibs/netutil"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestIPMut(t *testing.T) {
+	testIPs := []net.IP{{
+		127, 0, 0, 1,
+	}, {
+		192, 168, 0, 1,
+	}, {
+		8, 8, 8, 8,
+	}}
+
+	t.Run("nil_no_mut", func(t *testing.T) {
+		ipmut := NewIPMut(nil)
+
+		ips := netutil.CloneIPs(testIPs)
+		for i := range ips {
+			ipmut.Load()(ips[i])
+			assert.True(t, ips[i].Equal(testIPs[i]))
+		}
+	})
+
+	t.Run("not_nil_mut", func(t *testing.T) {
+		ipmut := NewIPMut(func(ip net.IP) {
+			for i := range ip {
+				ip[i] = 0
+			}
+		})
+		want := netutil.IPv4Zero()
+
+		ips := netutil.CloneIPs(testIPs)
+		for i := range ips {
+			ipmut.Load()(ips[i])
+			assert.True(t, ips[i].Equal(want))
+		}
+	})
+}

internal/aghnet/net.go

@@ -42,8 +42,7 @@ func GatewayIP(ifaceName string) net.IP {
 
 	fields := strings.Fields(string(d))
 	// The meaningful "ip route" command output should contain the word
-	// "default" at first field and default gateway IP address at third
+	// "default" at first field and default gateway IP address at third field.
-	// field.
 	if len(fields) < 3 || fields[0] != "default" {
 		return nil
 	}
@@ -218,28 +217,6 @@ func IsAddrInUse(err error) (ok bool) {
 	return isAddrInUse(sysErr)
 }
 
-// SplitHost is a wrapper for net.SplitHostPort for the cases when the hostport
-// does not necessarily contain a port.
-func SplitHost(hostport string) (host string, err error) {
-	host, _, err = net.SplitHostPort(hostport)
-	if err != nil {
-		// Check for the missing port error.  If it is that error, just
-		// use the host as is.
-		//
-		// See the source code for net.SplitHostPort.
-		const missingPort = "missing port in address"
-
-		addrErr := &net.AddrError{}
-		if !errors.As(err, &addrErr) || addrErr.Err != missingPort {
-			return "", err
-		}
-
-		host = hostport
-	}
-
-	return host, nil
-}
-
 // CollectAllIfacesAddrs returns the slice of all network interfaces IP
 // addresses without port number.
 func CollectAllIfacesAddrs() (addrs []string, err error) {

internal/aghnet/net_test.go

@@ -15,12 +15,20 @@ func TestMain(m *testing.M) {
 	aghtest.DiscardLogOutput(m)
 }
 
-func TestGetValidNetInterfacesForWeb(t *testing.T) {
+func TestGetInterfaceByIP(t *testing.T) {
 	ifaces, err := GetValidNetInterfacesForWeb()
-	require.NoErrorf(t, err, "cannot get net interfaces: %s", err)
+	require.NoError(t, err)
-	require.NotEmpty(t, ifaces, "no net interfaces found")
+	require.NotEmpty(t, ifaces)
+
 	for _, iface := range ifaces {
-		require.NotEmptyf(t, iface.Addresses, "no addresses found for %s", iface.Name)
+		t.Run(iface.Name, func(t *testing.T) {
+			require.NotEmpty(t, iface.Addresses)
+
+			for _, ip := range iface.Addresses {
+				ifaceName := GetInterfaceByIP(ip)
+				require.Equal(t, iface.Name, ifaceName)
+			}
+		})
 	}
 }
 
@@ -73,18 +81,47 @@ func TestBroadcastFromIPNet(t *testing.T) {
 }
 
 func TestCheckPort(t *testing.T) {
-	l, err := net.Listen("tcp", "127.0.0.1:")
+	t.Run("tcp_bound", func(t *testing.T) {
-	require.NoError(t, err)
+		l, err := net.Listen("tcp", "127.0.0.1:")
-	testutil.CleanupAndRequireSuccess(t, l.Close)
+		require.NoError(t, err)
+		testutil.CleanupAndRequireSuccess(t, l.Close)
 
-	ipp := netutil.IPPortFromAddr(l.Addr())
+		ipp := netutil.IPPortFromAddr(l.Addr())
-	require.NotNil(t, ipp)
+		require.NotNil(t, ipp)
-	require.NotNil(t, ipp.IP)
+		require.NotNil(t, ipp.IP)
-	require.NotZero(t, ipp.Port)
+		require.NotZero(t, ipp.Port)
 
-	err = CheckPort("tcp", ipp.IP, ipp.Port)
+		err = CheckPort("tcp", ipp.IP, ipp.Port)
-	target := &net.OpError{}
+		target := &net.OpError{}
-	require.ErrorAs(t, err, &target)
+		require.ErrorAs(t, err, &target)
 
-	assert.Equal(t, "listen", target.Op)
+		assert.Equal(t, "listen", target.Op)
+	})
+
+	t.Run("udp_bound", func(t *testing.T) {
+		conn, err := net.ListenPacket("udp", "127.0.0.1:")
+		require.NoError(t, err)
+		testutil.CleanupAndRequireSuccess(t, conn.Close)
+
+		ipp := netutil.IPPortFromAddr(conn.LocalAddr())
+		require.NotNil(t, ipp)
+		require.NotNil(t, ipp.IP)
+		require.NotZero(t, ipp.Port)
+
+		err = CheckPort("udp", ipp.IP, ipp.Port)
+		target := &net.OpError{}
+		require.ErrorAs(t, err, &target)
+
+		assert.Equal(t, "listen", target.Op)
+	})
+
+	t.Run("bad_network", func(t *testing.T) {
+		err := CheckPort("bad_network", nil, 0)
+		assert.NoError(t, err)
+	})
+
+	t.Run("can_bind", func(t *testing.T) {
+		err := CheckPort("udp", net.IP{0, 0, 0, 0}, 0)
+		assert.NoError(t, err)
+	})
 }