Pull request 2245: 4923 gopacket DHCP vol.8

Updates #4923.

Squashed commit of the following:

commit 0bfccf8bc1e63c4f5a01ce7f268e767969b368a0
Merge: 305f9fe2f 0e5e8e4dd
Author: Eugene Burkov <E.Burkov@AdGuard.COM>
Date:   Wed Jul 3 15:12:43 2024 +0300

    Merge branch 'master' into 4923-gopacket-dhcp-vol.8

commit 305f9fe2fe
Author: Eugene Burkov <E.Burkov@AdGuard.COM>
Date:   Tue Jul 2 17:03:01 2024 +0300

    dhcpsvc: adjust interface

commit f05b9f42e2
Author: Eugene Burkov <E.Burkov@AdGuard.COM>
Date:   Tue Jul 2 16:59:39 2024 +0300

    dhcpsvc: use logger

commit 4779f945ba
Author: Eugene Burkov <E.Burkov@AdGuard.COM>
Date:   Tue Jul 2 14:59:22 2024 +0300

    dhcpsvc: add todo

commit ae1713e5f7
Author: Eugene Burkov <E.Burkov@AdGuard.COM>
Date:   Mon Jul 1 15:49:22 2024 +0300

    dhcpsvc: use slog
This commit is contained in:
Eugene Burkov 2024-07-03 15:29:54 +03:00
parent 0e5e8e4dde
commit beeb8f0522
9 changed files with 368 additions and 212 deletions

View file

@ -2,11 +2,12 @@ package dhcpsvc
import (
"fmt"
"slices"
"log/slog"
"time"
"github.com/AdguardTeam/golibs/errors"
"github.com/AdguardTeam/golibs/mapsutil"
"github.com/AdguardTeam/golibs/netutil"
"golang.org/x/exp/maps"
)
// Config is the configuration for the DHCP service.
@ -15,6 +16,9 @@ type Config struct {
// interface identified by its name.
Interfaces map[string]*InterfaceConfig
// Logger will be used to log the DHCP events.
Logger *slog.Logger
// LocalDomainName is the top-level domain name to use for resolving DHCP
// clients' hostnames.
LocalDomainName string
@ -38,36 +42,44 @@ type InterfaceConfig struct {
}
// Validate returns an error in conf if any.
//
// TODO(e.burkov): Unexport and rewrite the test.
func (conf *Config) Validate() (err error) {
switch {
case conf == nil:
return errNilConfig
case !conf.Enabled:
return nil
case conf.ICMPTimeout < 0:
return newMustErr("icmp timeout", "be non-negative", conf.ICMPTimeout)
}
var errs []error
if conf.ICMPTimeout < 0 {
err = newMustErr("icmp timeout", "be non-negative", conf.ICMPTimeout)
errs = append(errs, err)
}
err = netutil.ValidateDomainName(conf.LocalDomainName)
if err != nil {
// Don't wrap the error since it's informative enough as is.
return err
errs = append(errs, err)
}
if len(conf.Interfaces) == 0 {
return errNoInterfaces
errs = append(errs, errNoInterfaces)
return errors.Join(errs...)
}
ifaces := maps.Keys(conf.Interfaces)
slices.Sort(ifaces)
for _, iface := range ifaces {
if err = conf.Interfaces[iface].validate(); err != nil {
return fmt.Errorf("interface %q: %w", iface, err)
}
mapsutil.SortedRange(conf.Interfaces, func(iface string, ic *InterfaceConfig) (ok bool) {
err = ic.validate()
if err != nil {
errs = append(errs, fmt.Errorf("interface %q: %w", iface, err))
}
return nil
return true
})
return errors.Join(errs...)
}
// validate returns an error in ic, if any.

View file

@ -24,6 +24,7 @@ func TestConfig_Validate(t *testing.T) {
name: "empty",
conf: &dhcpsvc.Config{
Enabled: true,
Interfaces: testInterfaceConf,
},
wantErrMsg: `bad domain name "": domain name is empty`,
}, {

View file

@ -11,6 +11,14 @@ import (
"github.com/AdguardTeam/AdGuardHome/internal/next/agh"
)
const (
// keyInterface is the key for logging the network interface name.
keyInterface = "iface"
// keyFamily is the key for logging the handled address family.
keyFamily = "family"
)
// Interface is a DHCP service.
//
// TODO(e.burkov): Separate HostByIP, MACByIP, IPByHost into a separate
@ -50,21 +58,21 @@ type Interface interface {
// AddLease adds a new DHCP lease. l must be valid. It returns an error if
// l already exists.
AddLease(l *Lease) (err error)
AddLease(ctx context.Context, l *Lease) (err error)
// UpdateStaticLease replaces an existing static DHCP lease. l must be
// valid. It returns an error if the lease with the given hardware address
// doesn't exist or if other values match another existing lease.
UpdateStaticLease(l *Lease) (err error)
UpdateStaticLease(ctx context.Context, l *Lease) (err error)
// RemoveLease removes an existing DHCP lease. l must be valid. It returns
// an error if there is no lease equal to l.
RemoveLease(l *Lease) (err error)
RemoveLease(ctx context.Context, l *Lease) (err error)
// Reset removes all the DHCP leases.
//
// TODO(e.burkov): If it's really needed?
Reset() (err error)
Reset(ctx context.Context) (err error)
}
// Empty is an [Interface] implementation that does nothing.
@ -101,13 +109,13 @@ func (Empty) IPByHost(_ string) (ip netip.Addr) { return netip.Addr{} }
func (Empty) Leases() (leases []*Lease) { return nil }
// AddLease implements the [Interface] interface for Empty.
func (Empty) AddLease(_ *Lease) (err error) { return nil }
func (Empty) AddLease(_ context.Context, _ *Lease) (err error) { return nil }
// UpdateStaticLease implements the [Interface] interface for Empty.
func (Empty) UpdateStaticLease(_ *Lease) (err error) { return nil }
func (Empty) UpdateStaticLease(_ context.Context, _ *Lease) (err error) { return nil }
// RemoveLease implements the [Interface] interface for Empty.
func (Empty) RemoveLease(_ *Lease) (err error) { return nil }
func (Empty) RemoveLease(_ context.Context, _ *Lease) (err error) { return nil }
// Reset implements the [Interface] interface for Empty.
func (Empty) Reset() (err error) { return nil }
func (Empty) Reset(_ context.Context) (err error) { return nil }

View file

@ -2,6 +2,7 @@ package dhcpsvc
import (
"fmt"
"log/slog"
"slices"
"time"
)
@ -11,6 +12,9 @@ import (
//
// TODO(e.burkov): Add other methods as [DHCPServer] evolves.
type netInterface struct {
// logger logs the events related to the network interface.
logger *slog.Logger
// name is the name of the network interface.
name string

View file

@ -1,16 +1,17 @@
package dhcpsvc
import (
"context"
"fmt"
"log/slog"
"net"
"net/netip"
"slices"
"sync"
"sync/atomic"
"time"
"github.com/AdguardTeam/golibs/errors"
"golang.org/x/exp/maps"
"github.com/AdguardTeam/golibs/mapsutil"
)
// DHCPServer is a DHCP server for both IPv4 and IPv6 address families.
@ -19,6 +20,9 @@ type DHCPServer struct {
// information about its clients.
enabled *atomic.Bool
// logger logs common DHCP events.
logger *slog.Logger
// localTLD is the top-level domain name to use for resolving DHCP clients'
// hostnames.
localTLD string
@ -43,8 +47,11 @@ type DHCPServer struct {
// error if the given configuration can't be used.
//
// TODO(e.burkov): Use.
func New(conf *Config) (srv *DHCPServer, err error) {
func New(ctx context.Context, conf *Config) (srv *DHCPServer, err error) {
l := conf.Logger
if !conf.Enabled {
l.DebugContext(ctx, "disabled")
// TODO(e.burkov): Perhaps return [Empty]?
return nil, nil
}
@ -52,27 +59,26 @@ func New(conf *Config) (srv *DHCPServer, err error) {
// TODO(e.burkov): Add validations scoped to the network interfaces set.
ifaces4 := make(netInterfacesV4, 0, len(conf.Interfaces))
ifaces6 := make(netInterfacesV6, 0, len(conf.Interfaces))
var errs []error
ifaceNames := maps.Keys(conf.Interfaces)
slices.Sort(ifaceNames)
mapsutil.SortedRange(conf.Interfaces, func(name string, iface *InterfaceConfig) (cont bool) {
var i4 *netInterfaceV4
var i6 *netInterfaceV6
for _, ifaceName := range ifaceNames {
iface := conf.Interfaces[ifaceName]
i4, err = newNetInterfaceV4(ifaceName, iface.IPv4)
i4, err = newNetInterfaceV4(ctx, l, name, iface.IPv4)
if err != nil {
return nil, fmt.Errorf("interface %q: ipv4: %w", ifaceName, err)
errs = append(errs, fmt.Errorf("interface %q: ipv4: %w", name, err))
} else if i4 != nil {
ifaces4 = append(ifaces4, i4)
}
i6 = newNetInterfaceV6(ifaceName, iface.IPv6)
i6 := newNetInterfaceV6(ctx, l, name, iface.IPv6)
if i6 != nil {
ifaces6 = append(ifaces6, i6)
}
return true
})
if err = errors.Join(errs...); err != nil {
return nil, err
}
enabled := &atomic.Bool{}
@ -80,6 +86,7 @@ func New(conf *Config) (srv *DHCPServer, err error) {
srv = &DHCPServer{
enabled: enabled,
logger: l,
localTLD: conf.LocalDomainName,
leasesMu: &sync.RWMutex{},
leases: newLeaseIndex(),
@ -159,7 +166,7 @@ func (srv *DHCPServer) IPByHost(host string) (ip netip.Addr) {
}
// Reset implements the [Interface] interface for *DHCPServer.
func (srv *DHCPServer) Reset() (err error) {
func (srv *DHCPServer) Reset(ctx context.Context) (err error) {
srv.leasesMu.Lock()
defer srv.leasesMu.Unlock()
@ -171,11 +178,13 @@ func (srv *DHCPServer) Reset() (err error) {
}
srv.leases.clear()
srv.logger.DebugContext(ctx, "reset leases")
return nil
}
// AddLease implements the [Interface] interface for *DHCPServer.
func (srv *DHCPServer) AddLease(l *Lease) (err error) {
func (srv *DHCPServer) AddLease(ctx context.Context, l *Lease) (err error) {
defer func() { err = errors.Annotate(err, "adding lease: %w") }()
addr := l.IP
@ -188,13 +197,27 @@ func (srv *DHCPServer) AddLease(l *Lease) (err error) {
srv.leasesMu.Lock()
defer srv.leasesMu.Unlock()
return srv.leases.add(l, iface)
err = srv.leases.add(l, iface)
if err != nil {
// Don't wrap the error since there is already an annotation deferred.
return err
}
iface.logger.DebugContext(
ctx, "added lease",
"hostname", l.Hostname,
"ip", l.IP,
"mac", l.HWAddr,
"static", l.IsStatic,
)
return nil
}
// UpdateStaticLease implements the [Interface] interface for *DHCPServer.
//
// TODO(e.burkov): Support moving leases between interfaces.
func (srv *DHCPServer) UpdateStaticLease(l *Lease) (err error) {
func (srv *DHCPServer) UpdateStaticLease(ctx context.Context, l *Lease) (err error) {
defer func() { err = errors.Annotate(err, "updating static lease: %w") }()
addr := l.IP
@ -207,11 +230,25 @@ func (srv *DHCPServer) UpdateStaticLease(l *Lease) (err error) {
srv.leasesMu.Lock()
defer srv.leasesMu.Unlock()
return srv.leases.update(l, iface)
err = srv.leases.update(l, iface)
if err != nil {
// Don't wrap the error since there is already an annotation deferred.
return err
}
iface.logger.DebugContext(
ctx, "updated lease",
"hostname", l.Hostname,
"ip", l.IP,
"mac", l.HWAddr,
"static", l.IsStatic,
)
return nil
}
// RemoveLease implements the [Interface] interface for *DHCPServer.
func (srv *DHCPServer) RemoveLease(l *Lease) (err error) {
func (srv *DHCPServer) RemoveLease(ctx context.Context, l *Lease) (err error) {
defer func() { err = errors.Annotate(err, "removing lease: %w") }()
addr := l.IP
@ -224,7 +261,21 @@ func (srv *DHCPServer) RemoveLease(l *Lease) (err error) {
srv.leasesMu.Lock()
defer srv.leasesMu.Unlock()
return srv.leases.remove(l, iface)
err = srv.leases.remove(l, iface)
if err != nil {
// Don't wrap the error since there is already an annotation deferred.
return err
}
iface.logger.DebugContext(
ctx, "removed lease",
"hostname", l.Hostname,
"ip", l.IP,
"mac", l.HWAddr,
"static", l.IsStatic,
)
return nil
}
// ifaceForAddr returns the handled network interface for the given IP address,

View file

@ -8,6 +8,7 @@ import (
"time"
"github.com/AdguardTeam/AdGuardHome/internal/dhcpsvc"
"github.com/AdguardTeam/golibs/logutil/slogutil"
"github.com/AdguardTeam/golibs/testutil"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
@ -16,6 +17,12 @@ import (
// testLocalTLD is a common local TLD for tests.
const testLocalTLD = "local"
// testTimeout is a common timeout for tests and contexts.
const testTimeout time.Duration = 10 * time.Second
// discardLog is a logger to discard test output.
var discardLog = slogutil.NewDiscardLogger()
// testInterfaceConf is a common set of interface configurations for tests.
var testInterfaceConf = map[string]*dhcpsvc.InterfaceConfig{
"eth0": {
@ -103,6 +110,7 @@ func TestNew(t *testing.T) {
}{{
conf: &dhcpsvc.Config{
Enabled: true,
Logger: discardLog,
LocalDomainName: testLocalTLD,
Interfaces: map[string]*dhcpsvc.InterfaceConfig{
"eth0": {
@ -116,6 +124,7 @@ func TestNew(t *testing.T) {
}, {
conf: &dhcpsvc.Config{
Enabled: true,
Logger: discardLog,
LocalDomainName: testLocalTLD,
Interfaces: map[string]*dhcpsvc.InterfaceConfig{
"eth0": {
@ -129,6 +138,7 @@ func TestNew(t *testing.T) {
}, {
conf: &dhcpsvc.Config{
Enabled: true,
Logger: discardLog,
LocalDomainName: testLocalTLD,
Interfaces: map[string]*dhcpsvc.InterfaceConfig{
"eth0": {
@ -143,6 +153,7 @@ func TestNew(t *testing.T) {
}, {
conf: &dhcpsvc.Config{
Enabled: true,
Logger: discardLog,
LocalDomainName: testLocalTLD,
Interfaces: map[string]*dhcpsvc.InterfaceConfig{
"eth0": {
@ -156,17 +167,22 @@ func TestNew(t *testing.T) {
`range start 127.0.0.1 is not within 192.168.0.1/24`,
}}
ctx := testutil.ContextWithTimeout(t, testTimeout)
for _, tc := range testCases {
t.Run(tc.name, func(t *testing.T) {
_, err := dhcpsvc.New(tc.conf)
_, err := dhcpsvc.New(ctx, tc.conf)
testutil.AssertErrorMsg(t, tc.wantErrMsg, err)
})
}
}
func TestDHCPServer_AddLease(t *testing.T) {
srv, err := dhcpsvc.New(&dhcpsvc.Config{
ctx := testutil.ContextWithTimeout(t, testTimeout)
srv, err := dhcpsvc.New(ctx, &dhcpsvc.Config{
Enabled: true,
Logger: discardLog,
LocalDomainName: testLocalTLD,
Interfaces: testInterfaceConf,
})
@ -186,7 +202,7 @@ func TestDHCPServer_AddLease(t *testing.T) {
mac2 := mustParseMAC(t, "06:05:04:03:02:01")
mac3 := mustParseMAC(t, "02:03:04:05:06:07")
require.NoError(t, srv.AddLease(&dhcpsvc.Lease{
require.NoError(t, srv.AddLease(ctx, &dhcpsvc.Lease{
Hostname: host1,
IP: ip1,
HWAddr: mac1,
@ -261,14 +277,17 @@ func TestDHCPServer_AddLease(t *testing.T) {
for _, tc := range testCases {
t.Run(tc.name, func(t *testing.T) {
testutil.AssertErrorMsg(t, tc.wantErrMsg, srv.AddLease(tc.lease))
testutil.AssertErrorMsg(t, tc.wantErrMsg, srv.AddLease(ctx, tc.lease))
})
}
}
func TestDHCPServer_index(t *testing.T) {
srv, err := dhcpsvc.New(&dhcpsvc.Config{
ctx := testutil.ContextWithTimeout(t, testTimeout)
srv, err := dhcpsvc.New(ctx, &dhcpsvc.Config{
Enabled: true,
Logger: discardLog,
LocalDomainName: testLocalTLD,
Interfaces: testInterfaceConf,
})
@ -313,7 +332,7 @@ func TestDHCPServer_index(t *testing.T) {
IsStatic: true,
}}
for _, l := range leases {
require.NoError(t, srv.AddLease(l))
require.NoError(t, srv.AddLease(ctx, l))
}
t.Run("ip_idx", func(t *testing.T) {
@ -342,8 +361,11 @@ func TestDHCPServer_index(t *testing.T) {
}
func TestDHCPServer_UpdateStaticLease(t *testing.T) {
srv, err := dhcpsvc.New(&dhcpsvc.Config{
ctx := testutil.ContextWithTimeout(t, testTimeout)
srv, err := dhcpsvc.New(ctx, &dhcpsvc.Config{
Enabled: true,
Logger: discardLog,
LocalDomainName: testLocalTLD,
Interfaces: testInterfaceConf,
})
@ -386,7 +408,7 @@ func TestDHCPServer_UpdateStaticLease(t *testing.T) {
IsStatic: true,
}}
for _, l := range leases {
require.NoError(t, srv.AddLease(l))
require.NoError(t, srv.AddLease(ctx, l))
}
testCases := []struct {
@ -456,14 +478,17 @@ func TestDHCPServer_UpdateStaticLease(t *testing.T) {
for _, tc := range testCases {
t.Run(tc.name, func(t *testing.T) {
testutil.AssertErrorMsg(t, tc.wantErrMsg, srv.UpdateStaticLease(tc.lease))
testutil.AssertErrorMsg(t, tc.wantErrMsg, srv.UpdateStaticLease(ctx, tc.lease))
})
}
}
func TestDHCPServer_RemoveLease(t *testing.T) {
srv, err := dhcpsvc.New(&dhcpsvc.Config{
ctx := testutil.ContextWithTimeout(t, testTimeout)
srv, err := dhcpsvc.New(ctx, &dhcpsvc.Config{
Enabled: true,
Logger: discardLog,
LocalDomainName: testLocalTLD,
Interfaces: testInterfaceConf,
})
@ -495,7 +520,7 @@ func TestDHCPServer_RemoveLease(t *testing.T) {
IsStatic: true,
}}
for _, l := range leases {
require.NoError(t, srv.AddLease(l))
require.NoError(t, srv.AddLease(ctx, l))
}
testCases := []struct {
@ -546,7 +571,7 @@ func TestDHCPServer_RemoveLease(t *testing.T) {
for _, tc := range testCases {
t.Run(tc.name, func(t *testing.T) {
testutil.AssertErrorMsg(t, tc.wantErrMsg, srv.RemoveLease(tc.lease))
testutil.AssertErrorMsg(t, tc.wantErrMsg, srv.RemoveLease(ctx, tc.lease))
})
}
@ -554,8 +579,11 @@ func TestDHCPServer_RemoveLease(t *testing.T) {
}
func TestDHCPServer_Reset(t *testing.T) {
srv, err := dhcpsvc.New(&dhcpsvc.Config{
ctx := testutil.ContextWithTimeout(t, testTimeout)
srv, err := dhcpsvc.New(ctx, &dhcpsvc.Config{
Enabled: true,
Logger: discardLog,
LocalDomainName: testLocalTLD,
Interfaces: testInterfaceConf,
})
@ -584,12 +612,12 @@ func TestDHCPServer_Reset(t *testing.T) {
}}
for _, l := range leases {
require.NoError(t, srv.AddLease(l))
require.NoError(t, srv.AddLease(ctx, l))
}
require.Len(t, srv.Leases(), len(leases))
require.NoError(t, srv.Reset())
require.NoError(t, srv.Reset(ctx))
assert.Empty(t, srv.Leases())
}

View file

@ -1,13 +1,15 @@
package dhcpsvc
import (
"context"
"fmt"
"log/slog"
"net"
"net/netip"
"slices"
"time"
"github.com/AdguardTeam/golibs/log"
"github.com/AdguardTeam/golibs/errors"
"github.com/AdguardTeam/golibs/netutil"
"github.com/google/gopacket/layers"
)
@ -43,25 +45,133 @@ type IPv4Config struct {
}
// validate returns an error in conf if any.
func (conf *IPv4Config) validate() (err error) {
switch {
case conf == nil:
func (c *IPv4Config) validate() (err error) {
if c == nil {
return errNilConfig
case !conf.Enabled:
return nil
case !conf.GatewayIP.Is4():
return newMustErr("gateway ip", "be a valid ipv4", conf.GatewayIP)
case !conf.SubnetMask.Is4():
return newMustErr("subnet mask", "be a valid ipv4 cidr mask", conf.SubnetMask)
case !conf.RangeStart.Is4():
return newMustErr("range start", "be a valid ipv4", conf.RangeStart)
case !conf.RangeEnd.Is4():
return newMustErr("range end", "be a valid ipv4", conf.RangeEnd)
case conf.LeaseDuration <= 0:
return newMustErr("lease duration", "be less than %d", conf.LeaseDuration)
default:
} else if !c.Enabled {
return nil
}
var errs []error
if !c.GatewayIP.Is4() {
err = newMustErr("gateway ip", "be a valid ipv4", c.GatewayIP)
errs = append(errs, err)
}
if !c.SubnetMask.Is4() {
err = newMustErr("subnet mask", "be a valid ipv4 cidr mask", c.SubnetMask)
errs = append(errs, err)
}
if !c.RangeStart.Is4() {
err = newMustErr("range start", "be a valid ipv4", c.RangeStart)
errs = append(errs, err)
}
if !c.RangeEnd.Is4() {
err = newMustErr("range end", "be a valid ipv4", c.RangeEnd)
errs = append(errs, err)
}
if c.LeaseDuration <= 0 {
err = newMustErr("icmp timeout", "be positive", c.LeaseDuration)
errs = append(errs, err)
}
return errors.Join(errs...)
}
// netInterfaceV4 is a DHCP interface for IPv4 address family.
type netInterfaceV4 struct {
// gateway is the IP address of the network gateway.
gateway netip.Addr
// subnet is the network subnet.
subnet netip.Prefix
// addrSpace is the IPv4 address space allocated for leasing.
addrSpace ipRange
// implicitOpts are the options listed in Appendix A of RFC 2131 and
// initialized with default values. It must not have intersections with
// explicitOpts.
implicitOpts layers.DHCPOptions
// explicitOpts are the user-configured options. It must not have
// intersections with implicitOpts.
explicitOpts layers.DHCPOptions
// netInterface is embedded here to provide some common network interface
// logic.
netInterface
}
// newNetInterfaceV4 creates a new DHCP interface for IPv4 address family with
// the given configuration. It returns an error if the given configuration
// can't be used.
func newNetInterfaceV4(
ctx context.Context,
l *slog.Logger,
name string,
conf *IPv4Config,
) (i *netInterfaceV4, err error) {
l = l.With(
keyInterface, name,
keyFamily, netutil.AddrFamilyIPv4,
)
if !conf.Enabled {
l.DebugContext(ctx, "disabled")
return nil, nil
}
maskLen, _ := net.IPMask(conf.SubnetMask.AsSlice()).Size()
subnet := netip.PrefixFrom(conf.GatewayIP, maskLen)
switch {
case !subnet.Contains(conf.RangeStart):
return nil, fmt.Errorf("range start %s is not within %s", conf.RangeStart, subnet)
case !subnet.Contains(conf.RangeEnd):
return nil, fmt.Errorf("range end %s is not within %s", conf.RangeEnd, subnet)
}
addrSpace, err := newIPRange(conf.RangeStart, conf.RangeEnd)
if err != nil {
return nil, err
} else if addrSpace.contains(conf.GatewayIP) {
return nil, fmt.Errorf("gateway ip %s in the ip range %s", conf.GatewayIP, addrSpace)
}
i = &netInterfaceV4{
gateway: conf.GatewayIP,
subnet: subnet,
addrSpace: addrSpace,
netInterface: netInterface{
name: name,
leaseTTL: conf.LeaseDuration,
logger: l,
},
}
i.implicitOpts, i.explicitOpts = conf.options(ctx, l)
return i, nil
}
// netInterfacesV4 is a slice of network interfaces of IPv4 address family.
type netInterfacesV4 []*netInterfaceV4
// find returns the first network interface within ifaces containing ip. It
// returns false if there is no such interface.
func (ifaces netInterfacesV4) find(ip netip.Addr) (iface4 *netInterface, ok bool) {
i := slices.IndexFunc(ifaces, func(iface *netInterfaceV4) (contains bool) {
return iface.subnet.Contains(ip)
})
if i < 0 {
return nil, false
}
return &ifaces[i].netInterface, true
}
// options returns the implicit and explicit options for the interface. The two
@ -69,14 +179,14 @@ func (conf *IPv4Config) validate() (err error) {
// values.
//
// TODO(e.burkov): DRY with the IPv6 version.
func (conf *IPv4Config) options() (implicit, explicit layers.DHCPOptions) {
func (c *IPv4Config) options(ctx context.Context, l *slog.Logger) (imp, exp layers.DHCPOptions) {
// Set default values of host configuration parameters listed in Appendix A
// of RFC-2131.
implicit = layers.DHCPOptions{
imp = layers.DHCPOptions{
// Values From Configuration
layers.NewDHCPOption(layers.DHCPOptSubnetMask, conf.SubnetMask.AsSlice()),
layers.NewDHCPOption(layers.DHCPOptRouter, conf.GatewayIP.AsSlice()),
layers.NewDHCPOption(layers.DHCPOptSubnetMask, c.SubnetMask.AsSlice()),
layers.NewDHCPOption(layers.DHCPOptRouter, c.GatewayIP.AsSlice()),
// IP-Layer Per Host
@ -228,110 +338,29 @@ func (conf *IPv4Config) options() (implicit, explicit layers.DHCPOptions) {
// See https://datatracker.ietf.org/doc/html/rfc1122#section-4.2.3.6.
layers.NewDHCPOption(layers.DHCPOptTCPKeepAliveGarbage, []byte{0x1}),
}
slices.SortFunc(implicit, compareV4OptionCodes)
slices.SortFunc(imp, compareV4OptionCodes)
// Set values for explicitly configured options.
for _, exp := range conf.Options {
i, found := slices.BinarySearchFunc(implicit, exp, compareV4OptionCodes)
for _, o := range c.Options {
i, found := slices.BinarySearchFunc(imp, o, compareV4OptionCodes)
if found {
implicit = slices.Delete(implicit, i, i+1)
imp = slices.Delete(imp, i, i+1)
}
i, found = slices.BinarySearchFunc(explicit, exp, compareV4OptionCodes)
if exp.Length > 0 {
explicit = slices.Insert(explicit, i, exp)
i, found = slices.BinarySearchFunc(exp, o, compareV4OptionCodes)
if o.Length > 0 {
exp = slices.Insert(exp, i, o)
} else if found {
explicit = slices.Delete(explicit, i, i+1)
exp = slices.Delete(exp, i, i+1)
}
}
log.Debug("dhcpsvc: v4: implicit options: %s", implicit)
log.Debug("dhcpsvc: v4: explicit options: %s", explicit)
l.DebugContext(ctx, "options", "implicit", imp, "explicit", exp)
return implicit, explicit
return imp, exp
}
// compareV4OptionCodes compares option codes of a and b.
func compareV4OptionCodes(a, b layers.DHCPOption) (res int) {
return int(a.Type) - int(b.Type)
}
// netInterfaceV4 is a DHCP interface for IPv4 address family.
type netInterfaceV4 struct {
// gateway is the IP address of the network gateway.
gateway netip.Addr
// subnet is the network subnet.
subnet netip.Prefix
// addrSpace is the IPv4 address space allocated for leasing.
addrSpace ipRange
// implicitOpts are the options listed in Appendix A of RFC 2131 and
// initialized with default values. It must not have intersections with
// explicitOpts.
implicitOpts layers.DHCPOptions
// explicitOpts are the user-configured options. It must not have
// intersections with implicitOpts.
explicitOpts layers.DHCPOptions
// netInterface is embedded here to provide some common network interface
// logic.
netInterface
}
// newNetInterfaceV4 creates a new DHCP interface for IPv4 address family with
// the given configuration. It returns an error if the given configuration
// can't be used.
func newNetInterfaceV4(name string, conf *IPv4Config) (i *netInterfaceV4, err error) {
if !conf.Enabled {
return nil, nil
}
maskLen, _ := net.IPMask(conf.SubnetMask.AsSlice()).Size()
subnet := netip.PrefixFrom(conf.GatewayIP, maskLen)
switch {
case !subnet.Contains(conf.RangeStart):
return nil, fmt.Errorf("range start %s is not within %s", conf.RangeStart, subnet)
case !subnet.Contains(conf.RangeEnd):
return nil, fmt.Errorf("range end %s is not within %s", conf.RangeEnd, subnet)
}
addrSpace, err := newIPRange(conf.RangeStart, conf.RangeEnd)
if err != nil {
return nil, err
} else if addrSpace.contains(conf.GatewayIP) {
return nil, fmt.Errorf("gateway ip %s in the ip range %s", conf.GatewayIP, addrSpace)
}
i = &netInterfaceV4{
gateway: conf.GatewayIP,
subnet: subnet,
addrSpace: addrSpace,
netInterface: netInterface{
name: name,
leaseTTL: conf.LeaseDuration,
},
}
i.implicitOpts, i.explicitOpts = conf.options()
return i, nil
}
// netInterfacesV4 is a slice of network interfaces of IPv4 address family.
type netInterfacesV4 []*netInterfaceV4
// find returns the first network interface within ifaces containing ip. It
// returns false if there is no such interface.
func (ifaces netInterfacesV4) find(ip netip.Addr) (iface4 *netInterface, ok bool) {
i := slices.IndexFunc(ifaces, func(iface *netInterfaceV4) (contains bool) {
return iface.subnet.Contains(ip)
})
if i < 0 {
return nil, false
}
return &ifaces[i].netInterface, true
}

View file

@ -3,7 +3,10 @@ package dhcpsvc
import (
"net/netip"
"testing"
"time"
"github.com/AdguardTeam/golibs/logutil/slogutil"
"github.com/AdguardTeam/golibs/testutil"
"github.com/google/gopacket/layers"
"github.com/stretchr/testify/assert"
)
@ -75,9 +78,12 @@ func TestIPv4Config_Options(t *testing.T) {
wantExplicit: layers.DHCPOptions{opt1},
}}
ctx := testutil.ContextWithTimeout(t, time.Second)
l := slogutil.NewDiscardLogger()
for _, tc := range testCases {
t.Run(tc.name, func(t *testing.T) {
imp, exp := tc.conf.options()
imp, exp := tc.conf.options(ctx, l)
assert.Equal(t, tc.wantExplicit, exp)
for c := range exp {

View file

@ -1,12 +1,14 @@
package dhcpsvc
import (
"context"
"fmt"
"log/slog"
"net/netip"
"slices"
"time"
"github.com/AdguardTeam/golibs/log"
"github.com/AdguardTeam/golibs/errors"
"github.com/AdguardTeam/golibs/netutil"
"github.com/google/gopacket/layers"
)
@ -38,50 +40,26 @@ type IPv6Config struct {
}
// validate returns an error in conf if any.
func (conf *IPv6Config) validate() (err error) {
switch {
case conf == nil:
func (c *IPv6Config) validate() (err error) {
if c == nil {
return errNilConfig
case !conf.Enabled:
return nil
case !conf.RangeStart.Is6():
return fmt.Errorf("range start %s should be a valid ipv6", conf.RangeStart)
case conf.LeaseDuration <= 0:
return fmt.Errorf("lease duration %s must be positive", conf.LeaseDuration)
default:
} else if !c.Enabled {
return nil
}
}
// options returns the implicit and explicit options for the interface. The two
// lists are disjoint and the implicit options are initialized with default
// values.
//
// TODO(e.burkov): Add implicit options according to RFC.
func (conf *IPv6Config) options() (implicit, explicit layers.DHCPv6Options) {
// Set default values of host configuration parameters listed in RFC 8415.
implicit = layers.DHCPv6Options{}
slices.SortFunc(implicit, compareV6OptionCodes)
var errs []error
// Set values for explicitly configured options.
for _, exp := range conf.Options {
i, found := slices.BinarySearchFunc(implicit, exp, compareV6OptionCodes)
if found {
implicit = slices.Delete(implicit, i, i+1)
if !c.RangeStart.Is6() {
err = fmt.Errorf("range start %s should be a valid ipv6", c.RangeStart)
errs = append(errs, err)
}
explicit = append(explicit, exp)
if c.LeaseDuration <= 0 {
err = fmt.Errorf("lease duration %s must be positive", c.LeaseDuration)
errs = append(errs, err)
}
log.Debug("dhcpsvc: v6: implicit options: %s", implicit)
log.Debug("dhcpsvc: v6: explicit options: %s", explicit)
return implicit, explicit
}
// compareV6OptionCodes compares option codes of a and b.
func compareV6OptionCodes(a, b layers.DHCPv6Option) (res int) {
return int(a.Code) - int(b.Code)
return errors.Join(errs...)
}
// netInterfaceV6 is a DHCP interface for IPv6 address family.
@ -116,8 +94,16 @@ type netInterfaceV6 struct {
// the given configuration.
//
// TODO(e.burkov): Validate properly.
func newNetInterfaceV6(name string, conf *IPv6Config) (i *netInterfaceV6) {
func newNetInterfaceV6(
ctx context.Context,
l *slog.Logger,
name string,
conf *IPv6Config,
) (i *netInterfaceV6) {
l = l.With(keyInterface, name, keyFamily, netutil.AddrFamilyIPv6)
if !conf.Enabled {
l.DebugContext(ctx, "disabled")
return nil
}
@ -126,11 +112,12 @@ func newNetInterfaceV6(name string, conf *IPv6Config) (i *netInterfaceV6) {
netInterface: netInterface{
name: name,
leaseTTL: conf.LeaseDuration,
logger: l,
},
raSLAACOnly: conf.RASLAACOnly,
raAllowSLAAC: conf.RAAllowSLAAC,
}
i.implicitOpts, i.explicitOpts = conf.options()
i.implicitOpts, i.explicitOpts = conf.options(ctx, l)
return i
}
@ -159,3 +146,33 @@ func (ifaces netInterfacesV6) find(ip netip.Addr) (iface6 *netInterface, ok bool
return &ifaces[i].netInterface, true
}
// options returns the implicit and explicit options for the interface. The two
// lists are disjoint and the implicit options are initialized with default
// values.
//
// TODO(e.burkov): Add implicit options according to RFC.
func (c *IPv6Config) options(ctx context.Context, l *slog.Logger) (imp, exp layers.DHCPv6Options) {
// Set default values of host configuration parameters listed in RFC 8415.
imp = layers.DHCPv6Options{}
slices.SortFunc(imp, compareV6OptionCodes)
// Set values for explicitly configured options.
for _, e := range c.Options {
i, found := slices.BinarySearchFunc(imp, e, compareV6OptionCodes)
if found {
imp = slices.Delete(imp, i, i+1)
}
exp = append(exp, e)
}
l.DebugContext(ctx, "options", "implicit", imp, "explicit", exp)
return imp, exp
}
// compareV6OptionCodes compares option codes of a and b.
func compareV6OptionCodes(a, b layers.DHCPv6Option) (res int) {
return int(a.Code) - int(b.Code)
}