support subdomain matching in dns hosts

app/dns/config.go

@@ -1,18 +0,0 @@
-package dns
-
-import (
-	"net"
-)
-
-func (c *Config) GetInternalHosts() map[string]net.IP {
-	hosts := make(map[string]net.IP)
-	for domain, ipOrDomain := range c.GetHosts() {
-		address := ipOrDomain.AsAddress()
-		if address.Family().IsDomain() {
-			newError("ignoring domain address in static hosts: ", address.Domain()).AtWarning().WriteToLog()
-			continue
-		}
-		hosts[domain] = address.IP()
-	}
-	return hosts
-}

app/dns/config.pb.go

@@ -16,24 +16,49 @@ var _ = math.Inf
 // proto package needs to be updated.
 const _ = proto.ProtoPackageIsVersion2 // please upgrade the proto package
 
+type Config_HostMapping_Type int32
+
+const (
+	Config_HostMapping_Full      Config_HostMapping_Type = 0
+	Config_HostMapping_SubDomain Config_HostMapping_Type = 1
+)
+
+var Config_HostMapping_Type_name = map[int32]string{
+	0: "Full",
+	1: "SubDomain",
+}
+var Config_HostMapping_Type_value = map[string]int32{
+	"Full":      0,
+	"SubDomain": 1,
+}
+
+func (x Config_HostMapping_Type) String() string {
+	return proto.EnumName(Config_HostMapping_Type_name, int32(x))
+}
+func (Config_HostMapping_Type) EnumDescriptor() ([]byte, []int) {
+	return fileDescriptor_config_299ae69458dda3a0, []int{0, 2, 0}
+}
+
 type Config struct {
 	// Nameservers used by this DNS. Only traditional UDP servers are support at the moment.
 	// A special value 'localhost' as a domain address can be set to use DNS on local system.
 	NameServers []*net.Endpoint `protobuf:"bytes,1,rep,name=NameServers,proto3" json:"NameServers,omitempty"`
 	// Static hosts. Domain to IP.
-	Hosts map[string]*net.IPOrDomain `protobuf:"bytes,2,rep,name=Hosts,proto3" json:"Hosts,omitempty" protobuf_key:"bytes,1,opt,name=key,proto3" protobuf_val:"bytes,2,opt,name=value,proto3"`
+	// Deprecated. Use static_hosts.
+	Hosts map[string]*net.IPOrDomain `protobuf:"bytes,2,rep,name=Hosts,proto3" json:"Hosts,omitempty" protobuf_key:"bytes,1,opt,name=key,proto3" protobuf_val:"bytes,2,opt,name=value,proto3"` // Deprecated: Do not use.
 	// Client IP for EDNS client subnet.
-	ClientIp             *Config_ClientIP `protobuf:"bytes,3,opt,name=client_ip,json=clientIp,proto3" json:"client_ip,omitempty"`
-	XXX_NoUnkeyedLiteral struct{}         `json:"-"`
-	XXX_unrecognized     []byte           `json:"-"`
-	XXX_sizecache        int32            `json:"-"`
+	ClientIp             *Config_ClientIP      `protobuf:"bytes,3,opt,name=client_ip,json=clientIp,proto3" json:"client_ip,omitempty"`
+	StaticHosts          []*Config_HostMapping `protobuf:"bytes,4,rep,name=static_hosts,json=staticHosts,proto3" json:"static_hosts,omitempty"`
+	XXX_NoUnkeyedLiteral struct{}              `json:"-"`
+	XXX_unrecognized     []byte                `json:"-"`
+	XXX_sizecache        int32                 `json:"-"`
 }
 
 func (m *Config) Reset()         { *m = Config{} }
 func (m *Config) String() string { return proto.CompactTextString(m) }
 func (*Config) ProtoMessage()    {}
 func (*Config) Descriptor() ([]byte, []int) {
-	return fileDescriptor_config_209d2630698ab6f5, []int{0}
+	return fileDescriptor_config_299ae69458dda3a0, []int{0}
 }
 func (m *Config) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_Config.Unmarshal(m, b)
@@ -60,6 +85,7 @@ func (m *Config) GetNameServers() []*net.Endpoint {
 	return nil
 }
 
+// Deprecated: Do not use.
 func (m *Config) GetHosts() map[string]*net.IPOrDomain {
 	if m != nil {
 		return m.Hosts
@@ -74,6 +100,13 @@ func (m *Config) GetClientIp() *Config_ClientIP {
 	return nil
 }
 
+func (m *Config) GetStaticHosts() []*Config_HostMapping {
+	if m != nil {
+		return m.StaticHosts
+	}
+	return nil
+}
+
 type Config_ClientIP struct {
 	// IPv4 address of the client. Must be 4 bytes.
 	V4 []byte `protobuf:"bytes,1,opt,name=v4,proto3" json:"v4,omitempty"`
@@ -88,7 +121,7 @@ func (m *Config_ClientIP) Reset()         { *m = Config_ClientIP{} }
 func (m *Config_ClientIP) String() string { return proto.CompactTextString(m) }
 func (*Config_ClientIP) ProtoMessage()    {}
 func (*Config_ClientIP) Descriptor() ([]byte, []int) {
-	return fileDescriptor_config_209d2630698ab6f5, []int{0, 1}
+	return fileDescriptor_config_299ae69458dda3a0, []int{0, 1}
 }
 func (m *Config_ClientIP) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_Config_ClientIP.Unmarshal(m, b)
@@ -122,38 +155,100 @@ func (m *Config_ClientIP) GetV6() []byte {
 	return nil
 }
 
+type Config_HostMapping struct {
+	Type                 Config_HostMapping_Type `protobuf:"varint,1,opt,name=type,proto3,enum=v2ray.core.app.dns.Config_HostMapping_Type" json:"type,omitempty"`
+	Domain               string                  `protobuf:"bytes,2,opt,name=domain,proto3" json:"domain,omitempty"`
+	Ip                   [][]byte                `protobuf:"bytes,3,rep,name=ip,proto3" json:"ip,omitempty"`
+	XXX_NoUnkeyedLiteral struct{}                `json:"-"`
+	XXX_unrecognized     []byte                  `json:"-"`
+	XXX_sizecache        int32                   `json:"-"`
+}
+
+func (m *Config_HostMapping) Reset()         { *m = Config_HostMapping{} }
+func (m *Config_HostMapping) String() string { return proto.CompactTextString(m) }
+func (*Config_HostMapping) ProtoMessage()    {}
+func (*Config_HostMapping) Descriptor() ([]byte, []int) {
+	return fileDescriptor_config_299ae69458dda3a0, []int{0, 2}
+}
+func (m *Config_HostMapping) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_Config_HostMapping.Unmarshal(m, b)
+}
+func (m *Config_HostMapping) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_Config_HostMapping.Marshal(b, m, deterministic)
+}
+func (dst *Config_HostMapping) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_Config_HostMapping.Merge(dst, src)
+}
+func (m *Config_HostMapping) XXX_Size() int {
+	return xxx_messageInfo_Config_HostMapping.Size(m)
+}
+func (m *Config_HostMapping) XXX_DiscardUnknown() {
+	xxx_messageInfo_Config_HostMapping.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_Config_HostMapping proto.InternalMessageInfo
+
+func (m *Config_HostMapping) GetType() Config_HostMapping_Type {
+	if m != nil {
+		return m.Type
+	}
+	return Config_HostMapping_Full
+}
+
+func (m *Config_HostMapping) GetDomain() string {
+	if m != nil {
+		return m.Domain
+	}
+	return ""
+}
+
+func (m *Config_HostMapping) GetIp() [][]byte {
+	if m != nil {
+		return m.Ip
+	}
+	return nil
+}
+
 func init() {
 	proto.RegisterType((*Config)(nil), "v2ray.core.app.dns.Config")
 	proto.RegisterMapType((map[string]*net.IPOrDomain)(nil), "v2ray.core.app.dns.Config.HostsEntry")
 	proto.RegisterType((*Config_ClientIP)(nil), "v2ray.core.app.dns.Config.ClientIP")
+	proto.RegisterType((*Config_HostMapping)(nil), "v2ray.core.app.dns.Config.HostMapping")
+	proto.RegisterEnum("v2ray.core.app.dns.Config_HostMapping_Type", Config_HostMapping_Type_name, Config_HostMapping_Type_value)
 }
 
 func init() {
-	proto.RegisterFile("v2ray.com/core/app/dns/config.proto", fileDescriptor_config_209d2630698ab6f5)
-}
-
-var fileDescriptor_config_209d2630698ab6f5 = []byte{
-	// 338 bytes of a gzipped FileDescriptorProto
-	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0x7c, 0x91, 0x51, 0x4b, 0xf3, 0x30,
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-	0xc5, 0x51, 0x37, 0xe8, 0x77, 0xb2, 0xde, 0x1f, 0x82, 0xb1, 0xcb, 0xce, 0xe6, 0x79, 0xcb, 0x53,
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-	0x5a, 0xab, 0x4a, 0xfc, 0x1f, 0x85, 0xd5, 0xc0, 0x99, 0xff, 0xe5, 0x61, 0x35, 0x70, 0xf3, 0xd0,
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-	0x00, 0x00,
+	proto.RegisterFile("v2ray.com/core/app/dns/config.proto", fileDescriptor_config_299ae69458dda3a0)
+}
+
+var fileDescriptor_config_299ae69458dda3a0 = []byte{
+	// 444 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0x8c, 0x92, 0xd1, 0x6e, 0xd3, 0x30,
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+	0x00, 0x00, 0xff, 0xff, 0xee, 0x90, 0x3f, 0xc9, 0x0c, 0x03, 0x00, 0x00,
 }

app/dns/config.proto

@@ -15,7 +15,8 @@ message Config {
   repeated v2ray.core.common.net.Endpoint NameServers = 1;
 
   // Static hosts. Domain to IP.
-  map<string, v2ray.core.common.net.IPOrDomain> Hosts = 2;
+  // Deprecated. Use static_hosts.
+  map<string, v2ray.core.common.net.IPOrDomain> Hosts = 2 [deprecated = true];
 
   message ClientIP {
     // IPv4 address of the client. Must be 4 bytes.
@@ -26,4 +27,17 @@ message Config {
 
   // Client IP for EDNS client subnet.
   ClientIP client_ip = 3;
+
+  message HostMapping {
+    enum Type {
+      Full = 0;
+      SubDomain = 1;
+    }
+
+    Type type = 1;
+    string domain = 2;
+    repeated bytes ip = 3;
+  }
+
+  repeated HostMapping static_hosts = 4;
 }

app/dns/hosts.go

@@ -0,0 +1,67 @@
+package dns
+
+import (
+	"v2ray.com/core/common"
+	"v2ray.com/core/common/net"
+	"v2ray.com/core/common/strmatcher"
+)
+
+type StaticHosts struct {
+	ips      map[uint32][]net.IP
+	matchers *strmatcher.MatcherGroup
+}
+
+var typeMap = map[Config_HostMapping_Type]strmatcher.Type{
+	Config_HostMapping_Full:      strmatcher.Full,
+	Config_HostMapping_SubDomain: strmatcher.Domain,
+}
+
+func NewStaticHosts(hosts []*Config_HostMapping, legacy map[string]*net.IPOrDomain) (*StaticHosts, error) {
+	g := strmatcher.NewMatcherGroup()
+	sh := &StaticHosts{
+		ips:      make(map[uint32][]net.IP),
+		matchers: g,
+	}
+
+	if legacy != nil {
+		for domain, ip := range legacy {
+			matcher, err := strmatcher.Full.New(domain)
+			common.Must(err)
+			id := g.Add(matcher)
+
+			address := ip.AsAddress()
+			if address.Family().IsDomain() {
+				return nil, newError("ignoring domain address in static hosts: ", address.Domain()).AtWarning()
+			}
+
+			sh.ips[id] = []net.IP{address.IP()}
+		}
+	}
+
+	for _, mapping := range hosts {
+		strMType, f := typeMap[mapping.Type]
+		if !f {
+			return nil, newError("unknown mapping type", mapping.Type).AtWarning()
+		}
+		matcher, err := strMType.New(mapping.Domain)
+		if err != nil {
+			return nil, newError("failed to create domain matcher").Base(err)
+		}
+		id := g.Add(matcher)
+		ips := make([]net.IP, len(mapping.Ip))
+		for idx, ip := range mapping.Ip {
+			ips[idx] = net.IP(ip)
+		}
+		sh.ips[id] = ips
+	}
+
+	return sh, nil
+}
+
+func (h *StaticHosts) LookupIP(domain string) []net.IP {
+	id := h.matchers.Match(domain)
+	if id == 0 {
+		return nil
+	}
+	return h.ips[id]
+}

app/dns/hosts_test.go

@@ -0,0 +1,44 @@
+package dns_test
+
+import (
+	"testing"
+
+	. "v2ray.com/core/app/dns"
+	. "v2ray.com/ext/assert"
+)
+
+func TestStaticHosts(t *testing.T) {
+	assert := With(t)
+
+	pb := []*Config_HostMapping{
+		{
+			Type:   Config_HostMapping_Full,
+			Domain: "v2ray.com",
+			Ip: [][]byte{
+				{1, 1, 1, 1},
+			},
+		},
+		{
+			Type:   Config_HostMapping_SubDomain,
+			Domain: "v2ray.cn",
+			Ip: [][]byte{
+				{2, 2, 2, 2},
+			},
+		},
+	}
+
+	hosts, err := NewStaticHosts(pb, nil)
+	assert(err, IsNil)
+
+	{
+		ips := hosts.LookupIP("v2ray.com")
+		assert(len(ips), Equals, 1)
+		assert([]byte(ips[0]), Equals, []byte{1, 1, 1, 1})
+	}
+
+	{
+		ips := hosts.LookupIP("www.v2ray.cn")
+		assert(len(ips), Equals, 1)
+		assert([]byte(ips[0]), Equals, []byte{2, 2, 2, 2})
+	}
+}

app/dns/server.go

@@ -14,7 +14,7 @@ import (
 
 type Server struct {
 	sync.Mutex
-	hosts    map[string]net.IP
+	hosts    *StaticHosts
 	servers  []NameServer
 	clientIP *Config_ClientIP
 }
@@ -22,12 +22,17 @@ type Server struct {
 func New(ctx context.Context, config *Config) (*Server, error) {
 	server := &Server{
 		servers: make([]NameServer, len(config.NameServers)),
-		hosts:   config.GetInternalHosts(),
 	}
 	if config.ClientIp != nil {
 		server.clientIP = config.ClientIp
 	}
 
+	hosts, err := NewStaticHosts(config.StaticHosts, config.Hosts)
+	if err != nil {
+		return nil, newError("failed to create hosts").Base(err)
+	}
+	server.hosts = hosts
+
 	v := core.MustFromContext(ctx)
 	if err := v.RegisterFeature((*core.DNSClient)(nil), server); err != nil {
 		return nil, newError("unable to register DNSClient.").Base(err)
@@ -65,8 +70,8 @@ func (s *Server) Close() error {
 }
 
 func (s *Server) LookupIP(domain string) ([]net.IP, error) {
-	if ip, found := s.hosts[domain]; found {
-		return []net.IP{ip}, nil
+	if ip := s.hosts.LookupIP(domain); len(ip) > 0 {
+		return ip, nil
 	}
 
 	var lastErr error