[client] Fix controller re-connection (#2758)

Rethink the peer reconnection implementation

client/internal/peer/ice/agent.go

@@ -0,0 +1,89 @@
+package ice
+
+import (
+	"github.com/netbirdio/netbird/client/internal/stdnet"
+	"github.com/pion/ice/v3"
+	"github.com/pion/randutil"
+	"github.com/pion/stun/v2"
+	log "github.com/sirupsen/logrus"
+	"runtime"
+	"time"
+)
+
+const (
+	lenUFrag   = 16
+	lenPwd     = 32
+	runesAlpha = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
+
+	iceKeepAliveDefault           = 4 * time.Second
+	iceDisconnectedTimeoutDefault = 6 * time.Second
+	// iceRelayAcceptanceMinWaitDefault is the same as in the Pion ICE package
+	iceRelayAcceptanceMinWaitDefault = 2 * time.Second
+)
+
+var (
+	failedTimeout = 6 * time.Second
+)
+
+func NewAgent(iFaceDiscover stdnet.ExternalIFaceDiscover, config Config, candidateTypes []ice.CandidateType, ufrag string, pwd string) (*ice.Agent, error) {
+	iceKeepAlive := iceKeepAlive()
+	iceDisconnectedTimeout := iceDisconnectedTimeout()
+	iceRelayAcceptanceMinWait := iceRelayAcceptanceMinWait()
+
+	transportNet, err := newStdNet(iFaceDiscover, config.InterfaceBlackList)
+	if err != nil {
+		log.Errorf("failed to create pion's stdnet: %s", err)
+	}
+
+	agentConfig := &ice.AgentConfig{
+		MulticastDNSMode:       ice.MulticastDNSModeDisabled,
+		NetworkTypes:           []ice.NetworkType{ice.NetworkTypeUDP4, ice.NetworkTypeUDP6},
+		Urls:                   config.StunTurn.Load().([]*stun.URI),
+		CandidateTypes:         candidateTypes,
+		InterfaceFilter:        stdnet.InterfaceFilter(config.InterfaceBlackList),
+		UDPMux:                 config.UDPMux,
+		UDPMuxSrflx:            config.UDPMuxSrflx,
+		NAT1To1IPs:             config.NATExternalIPs,
+		Net:                    transportNet,
+		FailedTimeout:          &failedTimeout,
+		DisconnectedTimeout:    &iceDisconnectedTimeout,
+		KeepaliveInterval:      &iceKeepAlive,
+		RelayAcceptanceMinWait: &iceRelayAcceptanceMinWait,
+		LocalUfrag:             ufrag,
+		LocalPwd:               pwd,
+	}
+
+	if config.DisableIPv6Discovery {
+		agentConfig.NetworkTypes = []ice.NetworkType{ice.NetworkTypeUDP4}
+	}
+
+	return ice.NewAgent(agentConfig)
+}
+
+func GenerateICECredentials() (string, string, error) {
+	ufrag, err := randutil.GenerateCryptoRandomString(lenUFrag, runesAlpha)
+	if err != nil {
+		return "", "", err
+	}
+
+	pwd, err := randutil.GenerateCryptoRandomString(lenPwd, runesAlpha)
+	if err != nil {
+		return "", "", err
+	}
+	return ufrag, pwd, nil
+}
+
+func CandidateTypes() []ice.CandidateType {
+	if hasICEForceRelayConn() {
+		return []ice.CandidateType{ice.CandidateTypeRelay}
+	}
+	// TODO: remove this once we have refactored userspace proxy into the bind package
+	if runtime.GOOS == "ios" {
+		return []ice.CandidateType{ice.CandidateTypeHost, ice.CandidateTypeServerReflexive}
+	}
+	return []ice.CandidateType{ice.CandidateTypeHost, ice.CandidateTypeServerReflexive, ice.CandidateTypeRelay}
+}
+
+func CandidateTypesP2P() []ice.CandidateType {
+	return []ice.CandidateType{ice.CandidateTypeHost, ice.CandidateTypeServerReflexive}
+}