refactor: move answer and offer handling to peer agent

This commit is contained in:
braginini 2021-04-15 21:59:44 +02:00
parent 4ba9c958b4
commit 6fa4077f04
2 changed files with 60 additions and 62 deletions

View File

@ -26,13 +26,9 @@ type PeerAgent struct {
signal *signal.Client
// a connection to a local Wireguard instance to proxy data
wgConn net.Conn
// an address of local Wireguard instance
wgAddr string
//
wgIface string
}
// NewPeerAgent creates a new PeerAgent with give local and remote Wireguard public keys and initializes an ICE Agent
// NewPeerAgent creates a new PeerAgent with given local and remote Wireguard public keys and initializes an ICE Agent
func NewPeerAgent(localKey string, remoteKey string, stunTurnURLS []*ice.URL, wgAddr string, signal *signal.Client,
wgIface string) (*PeerAgent, error) {
@ -61,22 +57,21 @@ func NewPeerAgent(localKey string, remoteKey string, stunTurnURLS []*ice.URL, wg
LocalKey: localKey,
RemoteKey: remoteKey,
iceAgent: iceAgent,
wgAddr: wgAddr,
conn: nil,
wgConn: wgConn,
signal: signal,
wgIface: wgIface,
}
err = peerAgent.onConnectionStateChange()
if err != nil {
//todo close agent
log.Errorf("failed starting listener on ICE connection state change %s", err)
return nil, err
}
err = peerAgent.onCandidate()
if err != nil {
log.Errorf("failed listening on ICE connection state changes %s", err)
log.Errorf("failed starting listener on ICE Candidate %s", err)
//todo close agent
return nil, err
}
@ -130,21 +125,20 @@ func (pa *PeerAgent) proxyToLocalWireguard() {
// 4. after connection has been established peer starts to:
// - proxy all local Wireguard's packets to the remote peer
// - proxy all incoming data from the remote peer to local Wireguard
func (pa *PeerAgent) OpenConnection(initiator bool) error {
func (pa *PeerAgent) OpenConnection(initiator bool) (*ice.Conn, error) {
// start gathering candidates
err := pa.iceAgent.GatherCandidates()
if err != nil {
return err
return nil, err
}
// by that time it should be already set
frag, pwd, err := pa.iceAgent.GetRemoteUserCredentials()
if err != nil {
log.Errorf("remote credentials are not set for remote peer %s", pa.RemoteKey)
return err
return nil, err
}
// initiate remote connection
// will block until connection was established
var conn *ice.Conn = nil
@ -156,17 +150,59 @@ func (pa *PeerAgent) OpenConnection(initiator bool) error {
if err != nil {
log.Fatalf("failed listening on local port %s", err)
return err
}
log.Infof("Local addr %s, remote addr %s", conn.LocalAddr(), conn.RemoteAddr())
pa.conn = conn
return conn, err
}
func (pa *PeerAgent) prepareConnection(msg *sProto.Message, initiator bool) (*signal.Credential, error) {
remoteCred, err := signal.UnMarshalCredential(msg)
if err != nil {
return nil, err
}
cred, err := pa.Authenticate(remoteCred)
if err != nil {
log.Errorf("error authenticating remote peer %s", msg.Key)
return nil, err
}
go func() {
pa.conn, err = pa.OpenConnection(initiator)
if err != nil {
log.Errorf("error opening connection to remote peer %s %s", msg.Key, err)
}
}()
return cred, nil
}
func (pa *PeerAgent) OnOffer(msg *sProto.Message) error {
cred, err := pa.prepareConnection(msg, false)
if err != nil {
return err
}
// notify the remote peer about our credentials
answer := signal.MarshalCredential(pa.LocalKey, pa.RemoteKey, &signal.Credential{
UFrag: cred.UFrag,
Pwd: cred.Pwd,
}, sProto.Message_ANSWER)
err = pa.signal.Send(answer)
if err != nil {
return err
}
return nil
}
func (pa *PeerAgent) OnAnswer(msg *sProto.Message) error {
return nil
_, err := pa.prepareConnection(msg, true)
return err
}
func (pa *PeerAgent) OnRemoteCandidate(msg *sProto.Message) error {
@ -236,7 +272,8 @@ func (pa *PeerAgent) onConnectionStateChange() error {
})
}
func (pa *PeerAgent) Start() error {
// OfferConnection starts sending a connection offer to a remote peer
func (pa *PeerAgent) OfferConnection() error {
localUFrag, localPwd, err := pa.iceAgent.GetLocalUserCredentials()
if err != nil {
return err

View File

@ -61,6 +61,8 @@ func (e *Engine) Start(privateKey string, peers []string) error {
return err
}
e.receiveSignal(myPubKey)
// initialize peer agents
for _, peer := range peers {
peerAgent, err := NewPeerAgent(myPubKey, peer, e.stunsTurns, fmt.Sprintf("127.0.0.1:%d", *wgPort), e.signal, e.wgIface)
@ -69,12 +71,8 @@ func (e *Engine) Start(privateKey string, peers []string) error {
return err
}
e.agents[myPubKey] = peerAgent
}
e.receiveSignal(myPubKey)
for _, pa := range e.agents {
err := pa.Start()
err = peerAgent.OfferConnection()
if err != nil {
log.Fatalf("failed starting agent %s %s", myPubKey, err)
return err
@ -97,34 +95,20 @@ func (e *Engine) receiveSignal(localKey string) {
return fmt.Errorf("unknown peer %s", msg.Key)
}
// the one who send offer (expects answer) is the initiator of teh connection
initiator := msg.Type == sProto.Message_ANSWER
switch msg.Type {
case sProto.Message_OFFER:
cred, err := e.handle(msg, peerAgent, initiator)
err := peerAgent.OnOffer(msg)
if err != nil {
log.Errorf("error handling OFFER from %s", msg.Key)
return err
}
// notify the remote peer about our credentials
answer := signal.MarshalCredential(peerAgent.LocalKey, peerAgent.RemoteKey, &signal.Credential{
UFrag: cred.UFrag,
Pwd: cred.Pwd,
}, sProto.Message_ANSWER)
err = e.signal.Send(answer)
if err != nil {
return err
}
return nil
case sProto.Message_ANSWER:
_, err := e.handle(msg, peerAgent, initiator)
err := peerAgent.OnAnswer(msg)
if err != nil {
log.Errorf("error handling ANSWER from %s", msg.Key)
return err
}
case sProto.Message_CANDIDATE:
err := peerAgent.OnRemoteCandidate(msg)
if err != nil {
@ -138,26 +122,3 @@ func (e *Engine) receiveSignal(localKey string) {
e.signal.WaitConnected()
}
func (e *Engine) handle(msg *sProto.Message, peerAgent *PeerAgent, initiator bool) (*signal.Credential, error) {
remoteCred, err := signal.UnMarshalCredential(msg)
if err != nil {
return nil, err
}
cred, err := peerAgent.Authenticate(remoteCred)
if err != nil {
log.Errorf("error authenticating remote peer %s", msg.Key)
return nil, err
}
go func() {
err = peerAgent.OpenConnection(initiator)
if err != nil {
log.Errorf("error opening connection to remote peer %s %s", msg.Key, err)
}
}()
return cred, nil
}