package router import ( "errors" "v2ray.com/core/app" "v2ray.com/core/app/dns" "v2ray.com/core/common/loader" "v2ray.com/core/common/log" v2net "v2ray.com/core/common/net" ) const ( APP_ID = app.ID(3) ) var ( ErrInvalidRule = errors.New("Invalid Rule") ErrNoRuleApplicable = errors.New("No rule applicable") ) type Router struct { domainStrategy Config_DomainStrategy rules []Rule cache *RoutingTable dnsServer dns.Server } func NewRouter(config *Config, space app.Space) *Router { r := &Router{ domainStrategy: config.DomainStrategy, cache: NewRoutingTable(), rules: make([]Rule, len(config.Rule)), } space.InitializeApplication(func() error { for idx, rule := range config.Rule { r.rules[idx].Tag = rule.Tag cond, err := rule.BuildCondition() if err != nil { return err } r.rules[idx].Condition = cond } if !space.HasApp(dns.APP_ID) { log.Error("Router: DNS is not found in the space.") return app.ErrMissingApplication } r.dnsServer = space.GetApp(dns.APP_ID).(dns.Server) return nil }) return r } func (this *Router) Release() { } // Private: Visible for testing. func (this *Router) ResolveIP(dest v2net.Destination) []v2net.Destination { ips := this.dnsServer.Get(dest.Address.Domain()) if len(ips) == 0 { return nil } dests := make([]v2net.Destination, len(ips)) for idx, ip := range ips { if dest.Network == v2net.Network_TCP { dests[idx] = v2net.TCPDestination(v2net.IPAddress(ip), dest.Port) } else { dests[idx] = v2net.UDPDestination(v2net.IPAddress(ip), dest.Port) } } return dests } func (this *Router) takeDetourWithoutCache(dest v2net.Destination) (string, error) { for _, rule := range this.rules { if rule.Apply(dest) { return rule.Tag, nil } } if this.domainStrategy == Config_IpIfNonMatch && dest.Address.Family().IsDomain() { log.Info("Router: Looking up IP for ", dest) ipDests := this.ResolveIP(dest) if ipDests != nil { for _, ipDest := range ipDests { log.Info("Router: Trying IP ", ipDest) for _, rule := range this.rules { if rule.Apply(ipDest) { return rule.Tag, nil } } } } } return "", ErrNoRuleApplicable } func (this *Router) TakeDetour(dest v2net.Destination) (string, error) { destStr := dest.String() found, tag, err := this.cache.Get(destStr) if !found { tag, err := this.takeDetourWithoutCache(dest) this.cache.Set(destStr, tag, err) return tag, err } return tag, err } type RouterFactory struct{} func (RouterFactory) Create(space app.Space, config interface{}) (app.Application, error) { router := NewRouter(config.(*Config), space) return router, nil } func (RouterFactory) AppId() app.ID { return APP_ID } func init() { app.RegisterApplicationFactory(loader.GetType(new(Config)), RouterFactory{}) }