From 36c7735b855f4388d0cf36fb2f26f1979809c217 Mon Sep 17 00:00:00 2001
From: Ainar Garipov <a.garipov@adguard.com>
Date: Wed, 25 Nov 2020 14:26:26 +0300
Subject: [PATCH] Pull request: dhcpd: fix interface ipv6 check
Merge in DNS/adguard-home from 2355-dhcpcheck-ipv6 to master
Updates #2335.
Squashed commit of the following:
commit 5ce1cc7bc244ba5dd4a065d47dec8884fa3d45e7
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date: Wed Nov 25 14:03:24 2020 +0300
dhcpd: fix loop exit condition
commit 32b4b946bfa30159326dc295fa1a2607b78172af
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date: Wed Nov 25 13:26:50 2020 +0300
dhcpd: fix interface ipv6 check
---
CHANGELOG.md | 7 ++++
internal/dhcpd/check_other_dhcp.go | 10 ++---
internal/dhcpd/db.go | 1 -
internal/dhcpd/nclient4/client_test.go | 8 ++--
internal/dhcpd/nclient4/conn_unix.go | 18 ++++-----
internal/dhcpd/nclient4/ipv4.go | 6 +--
internal/dhcpd/v46_windows.go | 51 ++++++------------------
internal/dhcpd/v6.go | 13 ++++--
internal/dhcpd/v6_test.go | 55 ++++++++++++++++++++++++++
9 files changed, 103 insertions(+), 66 deletions(-)
diff --git a/CHANGELOG.md b/CHANGELOG.md
index f12d2670..798bf950 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -30,6 +30,13 @@ and this project adheres to
[#2297]: https://github.com/AdguardTeam/AdGuardHome/issues/2297
[#2306]: https://github.com/AdguardTeam/AdGuardHome/issues/2306
+### Fixed
+
+- Incorrect detection of the IPv6 address of an interface as well as another
+ infinite loop in the `/dhcp/find_active_dhcp` HTTP API [#2355].
+
+[#2355]: https://github.com/AdguardTeam/AdGuardHome/issues/2355
+
## [v0.104.3] - 2020-11-19
diff --git a/internal/dhcpd/check_other_dhcp.go b/internal/dhcpd/check_other_dhcp.go
index aba9e446..e77a7801 100644
--- a/internal/dhcpd/check_other_dhcp.go
+++ b/internal/dhcpd/check_other_dhcp.go
@@ -94,12 +94,11 @@ func CheckIfOtherDHCPServersPresentV4(ifaceName string) (bool, error) {
continue
}
- if ok {
- return true, nil
- }
if err != nil {
return false, err
}
+
+ return ok, nil
}
}
@@ -216,12 +215,11 @@ func CheckIfOtherDHCPServersPresentV6(ifaceName string) (bool, error) {
continue
}
- if ok {
- return true, nil
- }
if err != nil {
return false, err
}
+
+ return ok, nil
}
}
diff --git a/internal/dhcpd/db.go b/internal/dhcpd/db.go
index b01f9635..2618f12e 100644
--- a/internal/dhcpd/db.go
+++ b/internal/dhcpd/db.go
@@ -74,7 +74,6 @@ func (s *Server) dbLoad() {
} else {
v6DynLeases = append(v6DynLeases, &lease)
}
-
} else {
if obj[i].Expiry == leaseExpireStatic {
staticLeases = append(staticLeases, &lease)
diff --git a/internal/dhcpd/nclient4/client_test.go b/internal/dhcpd/nclient4/client_test.go
index 353a9ed7..99f99640 100644
--- a/internal/dhcpd/nclient4/client_test.go
+++ b/internal/dhcpd/nclient4/client_test.go
@@ -79,7 +79,7 @@ func serveAndClient(ctx context.Context, responses [][]*dhcpv4.DHCPv4, opts ...C
return mc, serverConn
}
-func ComparePacket(got *dhcpv4.DHCPv4, want *dhcpv4.DHCPv4) error {
+func ComparePacket(got, want *dhcpv4.DHCPv4) error {
if got == nil && got == want {
return nil
}
@@ -92,7 +92,7 @@ func ComparePacket(got *dhcpv4.DHCPv4, want *dhcpv4.DHCPv4) error {
return nil
}
-func pktsExpected(got []*dhcpv4.DHCPv4, want []*dhcpv4.DHCPv4) error {
+func pktsExpected(got, want []*dhcpv4.DHCPv4) error {
if len(got) != len(want) {
return fmt.Errorf("got %d packets, want %d packets", len(got), len(want))
}
@@ -309,10 +309,10 @@ func TestMultipleSendAndRead(t *testing.T) {
newPacket(dhcpv4.OpcodeBootRequest, [4]byte{0x44, 0x44, 0x44, 0x44}),
},
server: [][]*dhcpv4.DHCPv4{
- []*dhcpv4.DHCPv4{ // Response for first packet.
+ { // Response for first packet.
newPacket(dhcpv4.OpcodeBootReply, [4]byte{0x33, 0x33, 0x33, 0x33}),
},
- []*dhcpv4.DHCPv4{ // Response for second packet.
+ { // Response for second packet.
newPacket(dhcpv4.OpcodeBootReply, [4]byte{0x44, 0x44, 0x44, 0x44}),
},
},
diff --git a/internal/dhcpd/nclient4/conn_unix.go b/internal/dhcpd/nclient4/conn_unix.go
index 51ec98cb..39009d69 100644
--- a/internal/dhcpd/nclient4/conn_unix.go
+++ b/internal/dhcpd/nclient4/conn_unix.go
@@ -17,17 +17,13 @@ import (
"github.com/u-root/u-root/pkg/uio"
)
-var (
- // BroadcastMac is the broadcast MAC address.
- //
- // Any UDP packet sent to this address is broadcast on the subnet.
- BroadcastMac = net.HardwareAddr([]byte{255, 255, 255, 255, 255, 255})
-)
+// BroadcastMac is the broadcast MAC address.
+//
+// Any UDP packet sent to this address is broadcast on the subnet.
+var BroadcastMac = net.HardwareAddr([]byte{255, 255, 255, 255, 255, 255})
-var (
- // ErrUDPAddrIsRequired is an error used when a passed argument is not of type "*net.UDPAddr".
- ErrUDPAddrIsRequired = errors.New("must supply UDPAddr")
-)
+// ErrUDPAddrIsRequired is an error used when a passed argument is not of type "*net.UDPAddr".
+var ErrUDPAddrIsRequired = errors.New("must supply UDPAddr")
// NewRawUDPConn returns a UDP connection bound to the interface and port
// given based on a raw packet socket. All packets are broadcasted.
@@ -68,7 +64,7 @@ func NewBroadcastUDPConn(rawPacketConn net.PacketConn, boundAddr *net.UDPAddr) n
}
}
-func udpMatch(addr *net.UDPAddr, bound *net.UDPAddr) bool {
+func udpMatch(addr, bound *net.UDPAddr) bool {
if bound == nil {
return true
}
diff --git a/internal/dhcpd/nclient4/ipv4.go b/internal/dhcpd/nclient4/ipv4.go
index 5d961852..50a2d684 100644
--- a/internal/dhcpd/nclient4/ipv4.go
+++ b/internal/dhcpd/nclient4/ipv4.go
@@ -281,7 +281,7 @@ func (b UDP) Checksum() uint16 {
// CalculateChecksum calculates the checksum of the udp packet, given the total
// length of the packet and the checksum of the network-layer pseudo-header
// (excluding the total length) and the checksum of the payload.
-func (b UDP) CalculateChecksum(partialChecksum uint16, totalLen uint16) uint16 {
+func (b UDP) CalculateChecksum(partialChecksum, totalLen uint16) uint16 {
// Add the length portion of the checksum to the pseudo-checksum.
tmp := make([]byte, 2)
binary.BigEndian.PutUint16(tmp, totalLen)
@@ -336,13 +336,13 @@ func ChecksumCombine(a, b uint16) uint16 {
// given destination protocol and network address, ignoring the length
// field. Pseudo-headers are needed by transport layers when calculating
// their own checksum.
-func PseudoHeaderChecksum(protocol TransportProtocolNumber, srcAddr net.IP, dstAddr net.IP) uint16 {
+func PseudoHeaderChecksum(protocol TransportProtocolNumber, srcAddr, dstAddr net.IP) uint16 {
xsum := Checksum([]byte(srcAddr), 0)
xsum = Checksum([]byte(dstAddr), xsum)
return Checksum([]byte{0, uint8(protocol)}, xsum)
}
-func udp4pkt(packet []byte, dest *net.UDPAddr, src *net.UDPAddr) []byte {
+func udp4pkt(packet []byte, dest, src *net.UDPAddr) []byte {
ipLen := IPv4MinimumSize
udpLen := UDPMinimumSize
diff --git a/internal/dhcpd/v46_windows.go b/internal/dhcpd/v46_windows.go
index 152899b9..ebae25af 100644
--- a/internal/dhcpd/v46_windows.go
+++ b/internal/dhcpd/v46_windows.go
@@ -7,41 +7,16 @@ import "net"
type winServer struct {
}
-func (s *winServer) ResetLeases(leases []*Lease) {
-}
-func (s *winServer) GetLeases(flags int) []Lease {
- return nil
-}
-func (s *winServer) GetLeasesRef() []*Lease {
- return nil
-}
-func (s *winServer) AddStaticLease(lease Lease) error {
- return nil
-}
-func (s *winServer) RemoveStaticLease(l Lease) error {
- return nil
-}
-func (s *winServer) FindMACbyIP(ip net.IP) net.HardwareAddr {
- return nil
-}
-
-func (s *winServer) WriteDiskConfig4(c *V4ServerConf) {
-}
-func (s *winServer) WriteDiskConfig6(c *V6ServerConf) {
-}
-
-func (s *winServer) Start() error {
- return nil
-}
-func (s *winServer) Stop() {
-}
-func (s *winServer) Reset() {
-}
-
-func v4Create(conf V4ServerConf) (DHCPServer, error) {
- return &winServer{}, nil
-}
-
-func v6Create(conf V6ServerConf) (DHCPServer, error) {
- return &winServer{}, nil
-}
+func (s *winServer) ResetLeases(leases []*Lease) {}
+func (s *winServer) GetLeases(flags int) []Lease { return nil }
+func (s *winServer) GetLeasesRef() []*Lease { return nil }
+func (s *winServer) AddStaticLease(lease Lease) error { return nil }
+func (s *winServer) RemoveStaticLease(l Lease) error { return nil }
+func (s *winServer) FindMACbyIP(ip net.IP) net.HardwareAddr { return nil }
+func (s *winServer) WriteDiskConfig4(c *V4ServerConf) {}
+func (s *winServer) WriteDiskConfig6(c *V6ServerConf) {}
+func (s *winServer) Start() error { return nil }
+func (s *winServer) Stop() {}
+func (s *winServer) Reset() {}
+func v4Create(conf V4ServerConf) (DHCPServer, error) { return &winServer{}, nil }
+func v6Create(conf V6ServerConf) (DHCPServer, error) { return &winServer{}, nil }
diff --git a/internal/dhcpd/v6.go b/internal/dhcpd/v6.go
index b24be499..f1ec57b3 100644
--- a/internal/dhcpd/v6.go
+++ b/internal/dhcpd/v6.go
@@ -537,8 +537,12 @@ func (s *v6Server) packetHandler(conn net.PacketConn, peer net.Addr, req dhcpv6.
}
}
+type netIface interface {
+ Addrs() ([]net.Addr, error)
+}
+
// ifaceIPv6Addrs returns the interface's IPv6 addresses.
-func ifaceIPv6Addrs(iface *net.Interface) (ips []net.IP, err error) {
+func ifaceIPv6Addrs(iface netIface) (ips []net.IP, err error) {
addrs, err := iface.Addrs()
if err != nil {
return nil, err
@@ -550,8 +554,11 @@ func ifaceIPv6Addrs(iface *net.Interface) (ips []net.IP, err error) {
continue
}
- if ip := ipnet.IP.To16(); ip != nil {
- ips = append(ips, ip)
+ if ip := ipnet.IP.To4(); ip == nil {
+ // Assume that net.(*Interface).Addrs can only return
+ // valid IPv4 and IPv6 addresses. Since this isn't an
+ // IPv4 address, it must be an IPv6 one.
+ ips = append(ips, ipnet.IP)
}
}
diff --git a/internal/dhcpd/v6_test.go b/internal/dhcpd/v6_test.go
index 7d7dd678..d51c695c 100644
--- a/internal/dhcpd/v6_test.go
+++ b/internal/dhcpd/v6_test.go
@@ -6,6 +6,7 @@ import (
"net"
"testing"
+ "github.com/AdguardTeam/AdGuardHome/internal/agherr"
"github.com/insomniacslk/dhcp/dhcpv6"
"github.com/insomniacslk/dhcp/iana"
"github.com/stretchr/testify/assert"
@@ -223,3 +224,57 @@ func TestV6GetDynamicLease(t *testing.T) {
assert.True(t, ip6InRange(net.ParseIP("2001::2"), net.ParseIP("2001::2")))
assert.True(t, ip6InRange(net.ParseIP("2001::2"), net.ParseIP("2001::3")))
}
+
+type fakeIface struct {
+ addrs []net.Addr
+ err error
+}
+
+// Addrs implements the netIface interface for *fakeIface.
+func (iface *fakeIface) Addrs() (addrs []net.Addr, err error) {
+ if iface.err != nil {
+ return nil, iface.err
+ }
+
+ return iface.addrs, nil
+}
+
+func TestIfaceIPv6Addrs(t *testing.T) {
+ ip := net.IP{1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 1, 2, 3, 4, 5, 6}
+ ip4 := net.IP{1, 2, 3, 4}
+ addr := &net.IPNet{IP: ip}
+ errTest := agherr.Error("test error")
+
+ testCases := []struct {
+ name string
+ iface netIface
+ want []net.IP
+ wantErr error
+ }{{
+ name: "success",
+ iface: &fakeIface{addrs: []net.Addr{addr}, err: nil},
+ want: []net.IP{ip},
+ wantErr: nil,
+ }, {
+ name: "success_with_ipv4",
+ iface: &fakeIface{
+ addrs: []net.Addr{addr, &net.IPNet{IP: ip4}},
+ err: nil,
+ },
+ want: []net.IP{ip},
+ wantErr: nil,
+ }, {
+ name: "error",
+ iface: &fakeIface{addrs: []net.Addr{addr}, err: errTest},
+ want: nil,
+ wantErr: errTest,
+ }}
+
+ for _, tc := range testCases {
+ t.Run(tc.name, func(t *testing.T) {
+ got, gotErr := ifaceIPv6Addrs(tc.iface)
+ assert.Equal(t, tc.want, got)
+ assert.Equal(t, tc.wantErr, gotErr)
+ })
+ }
+}