change 128 bit IDs to 32 bit

build_mipsel.sh

@@ -0,0 +1 @@
+GOOS=linux GOMIPS=softfloat GOARCH=mipsle go build -v -a -trimpath -ldflags="-w -s" .

group.go

@@ -1,79 +0,0 @@
-package main
-
-import (
-	"fmt"
-	"net"
-	"time"
-
-	"kvas2-go/models"
-	"kvas2-go/netfilter-helper"
-
-	"github.com/coreos/go-iptables/iptables"
-)
-
-type Group struct {
-	*models.Group
-
-	Enabled bool
-
-	iptables    *iptables.IPTables
-	ipset       *netfilterHelper.IPSet
-	ipsetToLink *netfilterHelper.IPSetToLink
-}
-
-func (g *Group) AddIP(address net.IP, ttl time.Duration) error {
-	ttlSeconds := uint32(ttl.Seconds())
-	return g.ipset.AddIP(address, &ttlSeconds)
-}
-
-func (g *Group) DelIP(address net.IP) error {
-	return g.ipset.DelIP(address)
-}
-
-func (g *Group) ListIP() (map[string]*uint32, error) {
-	return g.ipset.ListIPs()
-}
-
-func (g *Group) Enable() error {
-	if g.Enabled {
-		return nil
-	}
-	defer func() {
-		if !g.Enabled {
-			_ = g.Disable()
-		}
-	}()
-
-	if g.FixProtect {
-		err := g.iptables.AppendUnique("filter", "_NDM_SL_FORWARD", "-o", g.Interface, "-m", "state", "--state", "NEW", "-j", "_NDM_SL_PROTECT")
-		if err != nil {
-			return fmt.Errorf("failed to fix protect: %w", err)
-		}
-	}
-
-	err := g.ipsetToLink.Enable()
-	if err != nil {
-		return err
-	}
-
-	g.Enabled = true
-
-	return nil
-}
-
-func (g *Group) Disable() []error {
-	var errs []error
-
-	if !g.Enabled {
-		return nil
-	}
-
-	err := g.ipsetToLink.Disable()
-	if err != nil {
-		errs = append(errs, err...)
-	}
-
-	g.Enabled = false
-
-	return errs
-}

group/group.go

@@ -0,0 +1,183 @@
+package group
+
+import (
+	"fmt"
+	"net"
+	"time"
+
+	"kvas2-go/models"
+	"kvas2-go/netfilter-helper"
+	"kvas2-go/records"
+
+	"github.com/coreos/go-iptables/iptables"
+	"github.com/rs/zerolog/log"
+	"github.com/vishvananda/netlink"
+)
+
+type Group struct {
+	*models.Group
+
+	enabled     bool
+	iptables    *iptables.IPTables
+	ipset       *netfilterHelper.IPSet
+	ipsetToLink *netfilterHelper.IPSetToLink
+}
+
+func (g *Group) AddIP(address net.IP, ttl uint32) error {
+	return g.ipset.AddIP(address, &ttl)
+}
+
+func (g *Group) DelIP(address net.IP) error {
+	return g.ipset.DelIP(address)
+}
+
+func (g *Group) ListIP() (map[string]*uint32, error) {
+	return g.ipset.ListIPs()
+}
+
+func (g *Group) Enable() error {
+	if g.enabled {
+		return nil
+	}
+	defer func() {
+		if !g.enabled {
+			_ = g.Disable()
+		}
+	}()
+
+	if g.FixProtect {
+		err := g.iptables.AppendUnique("filter", "_NDM_SL_FORWARD", "-o", g.Interface, "-m", "state", "--state", "NEW", "-j", "_NDM_SL_PROTECT")
+		if err != nil {
+			return fmt.Errorf("failed to fix protect: %w", err)
+		}
+	}
+
+	err := g.ipsetToLink.Enable()
+	if err != nil {
+		return err
+	}
+
+	g.enabled = true
+
+	return nil
+}
+
+func (g *Group) Disable() []error {
+	var errs []error
+
+	if !g.enabled {
+		return nil
+	}
+
+	if g.FixProtect {
+		err := g.iptables.Delete("filter", "_NDM_SL_FORWARD", "-o", g.Interface, "-m", "state", "--state", "NEW", "-j", "_NDM_SL_PROTECT")
+		if err != nil {
+			errs = append(errs, fmt.Errorf("failed to remove fix protect: %w", err))
+		}
+	}
+
+	err := g.ipsetToLink.Disable()
+	if err != nil {
+		errs = append(errs, err...)
+	}
+
+	g.enabled = false
+
+	return errs
+}
+
+func (g *Group) Sync(records *records.Records) error {
+	now := time.Now()
+
+	addresses := make(map[string]uint32)
+	knownDomains := records.ListKnownDomains()
+	for _, domain := range g.Rules {
+		if !domain.IsEnabled() {
+			continue
+		}
+
+		for _, domainName := range knownDomains {
+			if !domain.IsMatch(domainName) {
+				continue
+			}
+
+			domainAddresses := records.GetARecords(domainName)
+			for _, address := range domainAddresses {
+				ttl := uint32(now.Sub(address.Deadline).Seconds())
+				if oldTTL, ok := addresses[string(address.Address)]; !ok || ttl > oldTTL {
+					addresses[string(address.Address)] = ttl
+				}
+			}
+		}
+	}
+
+	currentAddresses, err := g.ListIP()
+	if err != nil {
+		return fmt.Errorf("failed to get old ipset list: %w", err)
+	}
+
+	for addr, ttl := range addresses {
+		// TODO: Check TTL
+		if _, exists := currentAddresses[addr]; exists {
+			continue
+		}
+		ip := net.IP(addr)
+		err = g.AddIP(ip, ttl)
+		if err != nil {
+			log.Error().
+				Str("address", ip.String()).
+				Err(err).
+				Msg("failed to add address")
+		} else {
+			log.Trace().
+				Str("address", ip.String()).
+				Err(err).
+				Msg("add address")
+		}
+	}
+
+	for addr := range currentAddresses {
+		if _, ok := addresses[addr]; ok {
+			continue
+		}
+		ip := net.IP(addr)
+		err = g.DelIP(ip)
+		if err != nil {
+			log.Error().
+				Str("address", ip.String()).
+				Err(err).
+				Msg("failed to delete address")
+		} else {
+			log.Trace().
+				Str("address", ip.String()).
+				Err(err).
+				Msg("del address")
+		}
+	}
+
+	return nil
+}
+
+func (g *Group) NetfilterDHook(table string) error {
+	return g.ipsetToLink.NetfilterDHook(table)
+}
+
+func (g *Group) LinkUpdateHook(event netlink.LinkUpdate) error {
+	return g.ipsetToLink.LinkUpdateHook(event)
+}
+
+func NewGroup(group *models.Group, nh4 *netfilterHelper.NetfilterHelper, chainPrefix, ipsetNamePrefix string) (*Group, error) {
+	ipsetName := fmt.Sprintf("%s%8x", ipsetNamePrefix, group.ID)
+	ipset, err := nh4.IPSet(ipsetName)
+	if err != nil {
+		return nil, fmt.Errorf("failed to initialize ipset: %w", err)
+	}
+
+	ipsetToLink := nh4.IPSetToLink(fmt.Sprintf("%s%8x", chainPrefix, group.ID), group.Interface, ipsetName)
+	return &Group{
+		Group:       group,
+		iptables:    nh4.IPTables,
+		ipset:       ipset,
+		ipsetToLink: ipsetToLink,
+	}, nil
+}

kvas2.go

@@ -2,8 +2,11 @@ package main
 
 import (
 	"context"
+	"encoding/binary"
+	"encoding/hex"
 	"errors"
 	"fmt"
+	"math/rand"
 	"net"
 	"os"
 	"strconv"
@@ -11,11 +14,11 @@ import (
 	"time"
 
 	"kvas2-go/dns-mitm-proxy"
+	"kvas2-go/group"
 	"kvas2-go/models"
 	"kvas2-go/netfilter-helper"
 	"kvas2-go/records"
 
-	"github.com/google/uuid"
 	"github.com/miekg/dns"
 	"github.com/rs/zerolog/log"
 	"github.com/vishvananda/netlink"
@@ -27,12 +30,19 @@ var (
 	ErrGroupIDConflict = errors.New("group id conflict")
 )
 
+func randomId() [4]byte {
+	id := make([]byte, 4)
+	binary.BigEndian.PutUint32(id, rand.Uint32())
+	return [4]byte(id)
+}
+
 type Config struct {
-	MinimalTTL             time.Duration
+	AdditionalTTL          uint32
 	ChainPrefix            string
 	IpSetPrefix            string
 	LinkName               string
 	TargetDNSServerAddress string
+	TargetDNSServerPort    uint16
 	ListenDNSPort          uint16
 }
 
@@ -43,7 +53,7 @@ type App struct {
 	NetfilterHelper4 *netfilterHelper.NetfilterHelper
 	NetfilterHelper6 *netfilterHelper.NetfilterHelper
 	Records          *records.Records
-	Groups           map[uuid.UUID]*Group
+	Groups           map[[4]byte]*group.Group
 
 	Link netlink.Link
 
@@ -68,9 +78,9 @@ func (a *App) handleLink(event netlink.LinkUpdate) {
 					continue
 				}
 
-				err := group.ipsetToLink.LinkUpdateHook()
+				err := group.LinkUpdateHook(event)
 				if err != nil {
-					log.Error().Str("group", group.ID.String()).Err(err).Msg("error while handling interface up")
+					log.Error().Str("group", hex.EncodeToString(group.ID[:])).Err(err).Msg("error while handling interface up")
 				}
 			}
 		}
@@ -204,16 +214,16 @@ func (a *App) start(ctx context.Context) (err error) {
 				args := strings.Split(string(buf[:n]), ":")
 				if len(args) == 3 && args[0] == "netfilter.d" {
 					log.Debug().Str("table", args[2]).Msg("netfilter.d event")
-					err = a.dnsOverrider4.NetfilerDHook(args[2])
+					err = a.dnsOverrider4.NetfilterDHook(args[2])
 					if err != nil {
 						log.Error().Err(err).Msg("error while fixing iptables after netfilter.d")
 					}
-					err = a.dnsOverrider6.NetfilerDHook(args[2])
+					err = a.dnsOverrider6.NetfilterDHook(args[2])
 					if err != nil {
 						log.Error().Err(err).Msg("error while fixing iptables after netfilter.d")
 					}
 					for _, group := range a.Groups {
-						err := group.ipsetToLink.NetfilerDHook(args[2])
+						err := group.NetfilterDHook(args[2])
 						if err != nil {
 							log.Error().Err(err).Msg("error while fixing iptables after netfilter.d")
 						}
@@ -276,97 +286,17 @@ func (a *App) Start(ctx context.Context) (err error) {
 	return err
 }
 
-func (a *App) AddGroup(group *models.Group) error {
-	if _, exists := a.Groups[group.ID]; exists {
+func (a *App) AddGroup(groupModel *models.Group) error {
+	if _, exists := a.Groups[groupModel.ID]; exists {
 		return ErrGroupIDConflict
 	}
 
-	ipsetName := fmt.Sprintf("%s%8x", a.Config.IpSetPrefix, group.ID.ID())
-	ipset, err := a.NetfilterHelper4.IPSet(ipsetName)
+	grp, err := group.NewGroup(groupModel, a.NetfilterHelper4, a.Config.ChainPrefix, a.Config.IpSetPrefix)
 	if err != nil {
-		return fmt.Errorf("failed to initialize ipset: %w", err)
-	}
-
-	grp := &Group{
-		Group:       group,
-		iptables:    a.NetfilterHelper4.IPTables,
-		ipset:       ipset,
-		ipsetToLink: a.NetfilterHelper4.IPSetToLink(fmt.Sprintf("%sR_%8x", a.Config.ChainPrefix, group.ID.ID()), group.Interface, ipsetName, false),
+		return fmt.Errorf("failed to create group: %w", err)
 	}
 	a.Groups[grp.ID] = grp
-	return a.SyncGroup(grp)
-}
-
-func (a *App) SyncGroup(group *Group) error {
-	now := time.Now()
-
-	addresses := make(map[string]time.Duration)
-	knownDomains := a.Records.ListKnownDomains()
-	for _, domain := range group.Rules {
-		if !domain.IsEnabled() {
-			continue
-		}
-
-		for _, domainName := range knownDomains {
-			if !domain.IsMatch(domainName) {
-				continue
-			}
-
-			domainAddresses := a.Records.GetARecords(domainName)
-			for _, address := range domainAddresses {
-				ttl := now.Sub(address.Deadline)
-				if oldTTL, ok := addresses[string(address.Address)]; !ok || ttl > oldTTL {
-					addresses[string(address.Address)] = ttl
-				}
-			}
-		}
-	}
-
-	currentAddresses, err := group.ListIP()
-	if err != nil {
-		return fmt.Errorf("failed to get old ipset list: %w", err)
-	}
-
-	for addr, ttl := range addresses {
-		// TODO: Check TTL
-		if _, exists := currentAddresses[addr]; exists {
-			continue
-		}
-		ip := net.IP(addr)
-		err = group.AddIP(ip, ttl)
-		if err != nil {
-			log.Error().
-				Str("address", ip.String()).
-				Err(err).
-				Msg("failed to add address")
-		} else {
-			log.Trace().
-				Str("address", ip.String()).
-				Err(err).
-				Msg("add address")
-		}
-	}
-
-	for addr := range currentAddresses {
-		if _, ok := addresses[addr]; ok {
-			continue
-		}
-		ip := net.IP(addr)
-		err = group.DelIP(ip)
-		if err != nil {
-			log.Error().
-				Str("address", ip.String()).
-				Err(err).
-				Msg("failed to delete address")
-		} else {
-			log.Trace().
-				Str("address", ip.String()).
-				Err(err).
-				Msg("del address")
-		}
-	}
-
-	return nil
+	return grp.Sync(a.Records)
 }
 
 func (a *App) ListInterfaces() ([]net.Interface, error) {
@@ -395,10 +325,7 @@ func (a *App) processARecord(aRecord dns.A) {
 		Int("ttl", int(aRecord.Hdr.Ttl)).
 		Msg("processing a record")
 
-	ttlDuration := time.Duration(aRecord.Hdr.Ttl) * time.Second
-	if ttlDuration < a.Config.MinimalTTL {
-		ttlDuration = a.Config.MinimalTTL
-	}
+	ttlDuration := aRecord.Hdr.Ttl + a.Config.AdditionalTTL
 
 	a.Records.AddARecord(aRecord.Hdr.Name[:len(aRecord.Hdr.Name)-1], aRecord.A, ttlDuration)
 
@@ -441,10 +368,7 @@ func (a *App) processCNameRecord(cNameRecord dns.CNAME) {
 		Int("ttl", int(cNameRecord.Hdr.Ttl)).
 		Msg("processing cname record")
 
-	ttlDuration := time.Duration(cNameRecord.Hdr.Ttl) * time.Second
-	if ttlDuration < a.Config.MinimalTTL {
-		ttlDuration = a.Config.MinimalTTL
-	}
+	ttlDuration := cNameRecord.Hdr.Ttl + a.Config.AdditionalTTL
 
 	a.Records.AddCNameRecord(cNameRecord.Hdr.Name[:len(cNameRecord.Hdr.Name)-1], cNameRecord.Target, ttlDuration)
 
@@ -463,7 +387,7 @@ func (a *App) processCNameRecord(cNameRecord dns.CNAME) {
 					continue
 				}
 				for _, aRecord := range aRecords {
-					err := group.AddIP(aRecord.Address, now.Sub(aRecord.Deadline))
+					err := group.AddIP(aRecord.Address, uint32(now.Sub(aRecord.Deadline).Seconds()))
 					if err != nil {
 						log.Error().
 							Str("address", aRecord.Address.String()).
@@ -508,7 +432,7 @@ func New(config Config) (*App, error) {
 
 	app.DNSMITM = dnsMitmProxy.New()
 	app.DNSMITM.TargetDNSServerAddress = app.Config.TargetDNSServerAddress
-	app.DNSMITM.TargetDNSServerPort = 53
+	app.DNSMITM.TargetDNSServerPort = app.Config.TargetDNSServerPort
 	app.DNSMITM.RequestHook = func(clientAddr net.Addr, reqMsg dns.Msg, network string) (*dns.Msg, *dns.Msg, error) {
 		// TODO: Need to understand why it not works in proxy mode
 		if len(reqMsg.Question) == 1 && reqMsg.Question[0].Qtype == dns.TypePTR {
@@ -544,7 +468,7 @@ func New(config Config) (*App, error) {
 	}
 
 	app.Records = records.New()
-	app.Groups = make(map[uuid.UUID]*Group, 0)
+	app.Groups = make(map[[4]byte]*group.Group)
 
 	link, err := netlink.LinkByName(app.Config.LinkName)
 	if err != nil {
@@ -572,7 +496,7 @@ func New(config Config) (*App, error) {
 		return nil, fmt.Errorf("failed to clear iptables: %w", err)
 	}
 
-	app.Groups = make(map[uuid.UUID]*Group)
+	app.Groups = make(map[[4]byte]*group.Group)
 
 	return app, nil
 }

main.go

@@ -2,12 +2,11 @@ package main
 
 import (
 	"context"
-	"github.com/rs/zerolog"
 	"os"
 	"os/signal"
 	"syscall"
-	"time"
 
+	"github.com/rs/zerolog"
 	"github.com/rs/zerolog/log"
 )
 
@@ -15,12 +14,13 @@ func main() {
 	log.Logger = log.Output(zerolog.ConsoleWriter{Out: os.Stderr})
 
 	app, err := New(Config{
-		MinimalTTL:             time.Hour,
+		AdditionalTTL:          216000, // 1 hour
 		ChainPrefix:            "KVAS2_",
 		IpSetPrefix:            "kvas2_",
 		LinkName:               "br0",
 		TargetDNSServerAddress: "127.0.0.1",
-		ListenDNSPort:          7553,
+		TargetDNSServerPort:    53,
+		ListenDNSPort:          3553,
 	})
 	if err != nil {
 		log.Fatal().Err(err).Msg("failed to initialize application")

models/group.go

@@ -1,9 +1,7 @@
 package models
 
-import "github.com/google/uuid"
-
 type Group struct {
-	ID         uuid.UUID
+	ID         [4]byte
 	Name       string
 	Interface  string
 	Rules      []*Rule

models/rule.go

@@ -4,11 +4,10 @@ import (
 	"regexp"
 
 	"github.com/IGLOU-EU/go-wildcard/v2"
-	"github.com/google/uuid"
 )
 
 type Rule struct {
-	ID     uuid.UUID
+	ID     [4]byte
 	Name   string
 	Type   string
 	Rule   string

netfilter-helper/ipset-to-link.go

@@ -265,21 +265,21 @@ func (r *IPSetToLink) Disable() []error {
 	return errs
 }
 
-func (r *IPSetToLink) NetfilerDHook(table string) error {
+func (r *IPSetToLink) NetfilterDHook(table string) error {
 	if !r.enabled {
 		return nil
 	}
 	return r.insertIPTablesRules(table)
 }
 
-func (r *IPSetToLink) LinkUpdateHook() error {
-	if !r.enabled {
+func (r *IPSetToLink) LinkUpdateHook(event netlink.LinkUpdate) error {
+	if !r.enabled || event.Change != 1 || event.Link.Attrs().Name != r.IfaceName || event.Attrs().OperState != netlink.OperUp {
 		return nil
 	}
 	return r.insertIPRoute()
 }
 
-func (nh *NetfilterHelper) IPSetToLink(name string, ifaceName, ipsetName string, softwareMode bool) *IPSetToLink {
+func (nh *NetfilterHelper) IPSetToLink(name string, ifaceName, ipsetName string) *IPSetToLink {
 	return &IPSetToLink{
 		IPTables:  nh.IPTables,
 		ChainName: name,

netfilter-helper/port-remap.go

@@ -105,7 +105,7 @@ func (r *PortRemap) Disable() []error {
 	return errs
 }
 
-func (r *PortRemap) NetfilerDHook(table string) error {
+func (r *PortRemap) NetfilterDHook(table string) error {
 	if !r.enabled {
 		return nil
 	}

records/records.go

@@ -22,7 +22,7 @@ type Records struct {
 	records map[string]interface{}
 }
 
-func (r *Records) AddCNameRecord(domainName, alias string, ttl time.Duration) {
+func (r *Records) AddCNameRecord(domainName, alias string, ttl uint32) {
 	if domainName == alias {
 		return
 	}
@@ -30,16 +30,16 @@ func (r *Records) AddCNameRecord(domainName, alias string, ttl time.Duration) {
 	r.mux.Lock()
 	r.records[domainName] = &CNameRecord{
 		Alias:    alias,
-		Deadline: time.Now().Add(ttl),
+		Deadline: time.Now().Add(time.Duration(ttl) * time.Second),
 	}
 	r.mux.Unlock()
 }
 
-func (r *Records) AddARecord(domainName string, addr net.IP, ttl time.Duration) {
+func (r *Records) AddARecord(domainName string, addr net.IP, ttl uint32) {
 	r.mux.Lock()
 	defer r.mux.Unlock()
 
-	deadline := time.Now().Add(ttl)
+	deadline := time.Now().Add(time.Duration(ttl) * time.Second)
 
 	aRecords, _ := r.records[domainName].([]*ARecord)
 	for _, aRecord := range aRecords {