group client config requests

apipb/legacy.go

@@ -0,0 +1,220 @@
+// Copied from lantern-cloud: e57d588aa976ca9d1a8531c92972e20a7d1640f9
+//
+// This file should be kept in sync with lantern-cloud
+package apipb
+
+import (
+	"crypto/tls"
+	"encoding/base64"
+	"encoding/hex"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"math"
+	"net"
+	"strconv"
+	"strings"
+
+	commonconfig "github.com/getlantern/common/config"
+)
+
+// Values configured uniformly on all clients. Note that we have no mechanism for updating these
+// values for existing client-proxy assignments.
+const (
+	tlsClientHelloSplitting = false
+	tlsClientHelloID        = "HelloBrowser"
+)
+
+// For flashlight, since it doesn't accept an empty string.
+var defaultTLSSuites string
+
+func init() {
+	suites := make([]string, 0)
+	for _, suite := range tls.CipherSuites() {
+		suites = append(suites, fmt.Sprintf("0x%04x", suite.ID))
+	}
+
+	defaultTLSSuites = strings.Join(suites, ",")
+}
+
+// ProxyToLegacyConfig converts a ProxyConnectConfig to the legacy format
+func ProxyToLegacyConfig(cfg *ProxyConnectConfig) (*commonconfig.ProxyConfig, error) {
+	legacy := new(commonconfig.ProxyConfig)
+
+	legacy.Name = cfg.Name
+	legacy.Addr = fmt.Sprintf("%s:%d", cfg.Addr, cfg.Port)
+	legacy.Cert = string(cfg.CertPem)
+	legacy.AuthToken = cfg.AuthToken
+	legacy.Trusted = cfg.Trusted
+	legacy.Bias = 9 // bias clients towards using lantern-cloud proxies
+
+	if cfg.Location != nil {
+		legacy.Location = &commonconfig.ProxyConfig_ProxyLocation{
+			City:        cfg.Location.City,
+			Country:     cfg.Location.Country,
+			CountryCode: cfg.Location.CountryCode,
+			Latitude:    cfg.Location.Latitude,
+			Longitude:   cfg.Location.Longitude,
+		}
+	}
+
+	legacy.Track = cfg.Track
+	legacy.Region = "platinum" // TODO: is region required?
+
+	switch pCfg := cfg.ProtocolConfig.(type) {
+	case *ProxyConnectConfig_ConnectCfgTls:
+		legacy.PluggableTransport = "https"
+		// currently, lantern-cloud uses multiplexing for all https connections so we set the
+		// multiplexed addr to the same as the addr
+		legacy.MultiplexedAddr = legacy.Addr
+
+		// TLS-level config
+		legacy.TLSClientHelloSplitting = tlsClientHelloSplitting
+		legacy.TLSClientHelloID = tlsClientHelloID
+		legacy.TLSServerNameIndicator = pCfg.ConnectCfgTls.ServerNameIndicator
+
+		ss, err := serializeTLSSessionState(pCfg.ConnectCfgTls.SessionState)
+		if err != nil {
+			return nil, fmt.Errorf("serialize TLS session error: %w", err)
+		}
+
+		legacy.TLSClientSessionState = ss
+		legacy.PluggableTransportSettings = map[string]string{}
+
+		if pCfg.ConnectCfgTls.TlsFrag != "" {
+			legacy.PluggableTransportSettings["tlsfrag"] = pCfg.ConnectCfgTls.TlsFrag
+		}
+
+	case *ProxyConnectConfig_ConnectCfgTlsmasq:
+		legacy.PluggableTransport = "tlsmasq"
+
+		// TLS-level config
+		legacy.TLSClientHelloSplitting = tlsClientHelloSplitting
+		legacy.TLSClientHelloID = tlsClientHelloID
+
+		tlsmasqCfg := pCfg.ConnectCfgTlsmasq
+
+		tlsmasqOrigin, _, err := net.SplitHostPort(tlsmasqCfg.OriginAddr)
+		if err != nil {
+			return nil, fmt.Errorf("bad tlsmasq origin addr: %w", err)
+		}
+
+		tlsmasqSuites := strings.Join(tlsmasqCfg.TlsSupportedCipherSuites, ",")
+
+		// An empty list should indicate the default, but flashlight doesn't
+		// like that.
+		if len(tlsmasqCfg.TlsSupportedCipherSuites) == 0 {
+			tlsmasqSuites = defaultTLSSuites
+		}
+
+		legacy.PluggableTransportSettings = map[string]string{
+			"tlsmasq_secret":        hex.EncodeToString(tlsmasqCfg.Secret),
+			"tlsmasq_sni":           tlsmasqOrigin,
+			"tlsmasq_tlsminversion": tlsmasqCfg.TlsMinVersion,
+			"tlsmasq_suites":        tlsmasqSuites,
+		}
+
+		if pCfg.ConnectCfgTlsmasq.TlsFrag != "" {
+			legacy.PluggableTransportSettings["tlsfrag"] = pCfg.ConnectCfgTlsmasq.TlsFrag
+		}
+
+	case *ProxyConnectConfig_ConnectCfgShadowsocks:
+		legacy.PluggableTransport = "shadowsocks"
+		legacy.MultiplexedAddr = legacy.Addr
+
+		ssCfg := pCfg.ConnectCfgShadowsocks
+
+		legacy.PluggableTransportSettings = map[string]string{
+			"shadowsocks_secret":           ssCfg.Secret,
+			"shadowsocks_cipher":           ssCfg.Cipher,
+			"shadowsocks_prefix_generator": ssCfg.PrefixGenerator,
+			"shadowsocks_with_tls":         strconv.FormatBool(ssCfg.WithTls),
+		}
+
+	case *ProxyConnectConfig_ConnectCfgBroflake:
+		legacy.PluggableTransport = "broflake"
+		legacy.Addr = "broflake"
+
+		bbCfg := pCfg.ConnectCfgBroflake
+		legacy.StunServers = bbCfg.StunServers
+
+		legacy.PluggableTransportSettings = map[string]string{
+			"broflake_ctablesize":                  strconv.Itoa(int(bbCfg.CtableSize)),
+			"broflake_ptablesize":                  strconv.Itoa(int(bbCfg.PtableSize)),
+			"broflake_natfailtimeout":              strconv.Itoa(int(bbCfg.NatFailTimeout)),
+			"broflake_icefailtimeout":              strconv.Itoa(int(bbCfg.IceFailTimeout)),
+			"broflake_discoverysrv":                bbCfg.DiscoverySrv,
+			"broflake_endpoint":                    bbCfg.Endpoint,
+			"broflake_egress_server_name":          bbCfg.EgressServerName,
+			"broflake_egress_insecure_skip_verify": strconv.FormatBool(bbCfg.EgressInsecureSkipVerify),
+			"broflake_egress_ca":                   bbCfg.EgressCa,
+			"broflake_stunbatchsize":               strconv.Itoa(int(bbCfg.StunBatchSize)),
+		}
+
+		legacy.Bias = 10                  // bias clients toward broflake
+		legacy.AllowedDomains = []string{ // currently, we only send ad traffic through Broflake
+			"doubleclick.net",
+			"adservice.google.com",
+			"adservice.google.com.hk",
+			"adservice.google.co.jp",
+			"adservice.google.nl",
+			"googlesyndication.com",
+			"googletagservices.com",
+			"googleadservices.com",
+		}
+
+	case *ProxyConnectConfig_ConnectCfgStarbridge:
+		legacy.PluggableTransport = "starbridge"
+
+		legacy.PluggableTransportSettings = map[string]string{
+			"starbridge_public_key": pCfg.ConnectCfgStarbridge.PublicKey,
+		}
+
+	case *ProxyConnectConfig_ConnectCfgAlgeneva:
+		legacy.PluggableTransport = "algeneva"
+		legacy.PluggableTransportSettings = map[string]string{
+			"algeneva_strategy": pCfg.ConnectCfgAlgeneva.Strategy,
+		}
+	case *ProxyConnectConfig_ConnectCfgWater:
+		legacy.PluggableTransport = "water"
+		legacy.PluggableTransportSettings = map[string]string{
+			"water_wasm":      base64.StdEncoding.EncodeToString(pCfg.ConnectCfgWater.Wasm),
+			"water_transport": pCfg.ConnectCfgWater.Transport,
+		}
+
+	default:
+		return nil, fmt.Errorf("unsupported protocol config: %T", cfg.ProtocolConfig)
+	}
+
+	return legacy, nil
+}
+
+// serializeTLSSessionState serializes the input TLS session state. This format is the one expected
+// by clients in the legacy config. When we move away from the legacy config, clients can just read
+// the session state out of the protcol buffers message.
+func serializeTLSSessionState(ss *ProxyConnectConfig_TLSConfig_SessionState) (string, error) {
+	type sessionState struct {
+		SessionTicket []uint8
+		Vers          uint16
+		CipherSuite   uint16
+		MasterSecret  []byte
+	}
+
+	if ss.Version > math.MaxUint16 {
+		return "", errors.New("invalid version")
+	} else if ss.CipherSuite > math.MaxUint16 {
+		return "", errors.New("invalid cipher suite")
+	}
+
+	b, err := json.Marshal(sessionState{
+		SessionTicket: ss.SessionTicket,
+		Vers:          uint16(ss.Version),
+		CipherSuite:   uint16(ss.CipherSuite),
+		MasterSecret:  ss.MasterSecret,
+	})
+	if err != nil {
+		return "", fmt.Errorf("marshal error: %w", err)
+	}
+
+	return base64.StdEncoding.EncodeToString(b), nil
+}