commit 3caa83d84de681b3cd38f4c61cfef2e9bd091176 Author: Cecylia Bocovich <cohosh@torproject.org> Date: Tue Oct 26 15:40:32 2021 -0400 Modify handling of misconfigurations and defaults --- proxy/lib/snowflake.go | 34 ++++++++++++++++++++-------------- proxy/main.go | 8 ++++++-- 2 files changed, 26 insertions(+), 16 deletions(-) diff --git a/proxy/lib/snowflake.go b/proxy/lib/snowflake.go index bd50dc8..734657a 100644 --- a/proxy/lib/snowflake.go +++ b/proxy/lib/snowflake.go @@ -15,7 +15,8 @@ You may then start and stop the proxy. Stopping the proxy will close existing co the proxy will not poll for more clients. go func() { - proxy.Start() + err := proxy.Start() + // handle error } // ... @@ -46,16 +47,12 @@ import ( "github.com/pion/webrtc/v3" ) -// DefaultBrokerURL is the snowflake broker run at https://snowflake-broker.torproject.net const DefaultBrokerURL = "https://snowflake-broker.torproject.net/" -// DefaultProbeURL is run at https://snowflake-broker.torproject.net:8443/probe const DefaultProbeURL = "https://snowflake-broker.torproject.net:8443/probe" -// DefaultRelayURL is run at wss://snowflake.torproject.net const DefaultRelayURL = "wss://snowflake.bamsoftware.com/" -// DefaultSTUNURL is run at stun:stun.stunprotocol.org:3478 const DefaultSTUNURL = "stun:stun.stunprotocol.org:3478" const pollInterval = 5 * time.Second @@ -486,27 +483,35 @@ func (sf *SnowflakeProxy) runSession(sid string) { // Start configures and starts a Snowflake, fully formed and special. Configuration // values that are unset will default to their corresponding default values. -func (sf *SnowflakeProxy) Start() { +func (sf *SnowflakeProxy) Start() error { + var err error + log.Println("starting") sf.shutdown = make(chan struct{}) - log.SetFlags(log.LstdFlags | log.LUTC) - - log.Println("starting") + // blank configurations revert to default + if sf.BrokerURL == "" { + sf.BrokerURL = DefaultBrokerURL + } + if sf.RelayURL == "" { + sf.RelayURL = DefaultRelayURL + } + if sf.STUNURL == "" { + sf.STUNURL = DefaultSTUNURL + } - var err error broker, err = newSignalingServer(sf.BrokerURL, sf.KeepLocalAddresses) if err != nil { - log.Fatal(err) + return fmt.Errorf("error configuring broker: %s", err) } _, err = url.Parse(sf.STUNURL) if err != nil { - log.Fatalf("invalid stun url: %s", err) + return fmt.Errorf("invalid stun url: %s", err) } _, err = url.Parse(sf.RelayURL) if err != nil { - log.Fatalf("invalid relay url: %s", err) + return fmt.Errorf("invalid relay url: %s", err) } config = webrtc.Configuration{ @@ -528,13 +533,14 @@ func (sf *SnowflakeProxy) Start() { for ; true; <-ticker.C { select { case <-sf.shutdown: - return + return nil default: tokens.get() sessionID := genSessionID() sf.runSession(sessionID) } } + return nil } // Stop closes all existing connections and shuts down the Snowflake. diff --git a/proxy/main.go b/proxy/main.go index aabac51..368589c 100644 --- a/proxy/main.go +++ b/proxy/main.go @@ -11,7 +11,7 @@ import ( ) func main() { - capacity := flag.Int("capacity", 10, "maximum concurrent clients") + capacity := flag.Uint("capacity", 0, "maximum concurrent clients") stunURL := flag.String("stun", sf.DefaultSTUNURL, "broker URL") logFilename := flag.String("log", "", "log filename") rawBrokerURL := flag.String("broker", sf.DefaultBrokerURL, "broker URL") @@ -32,6 +32,7 @@ func main() { var logOutput io.Writer = os.Stderr log.SetFlags(log.LstdFlags | log.LUTC) + log.SetFlags(log.LstdFlags | log.LUTC) if *logFilename != "" { f, err := os.OpenFile(*logFilename, os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0600) if err != nil { @@ -46,5 +47,8 @@ func main() { log.SetOutput(&safelog.LogScrubber{Output: logOutput}) } - proxy.Start() + err := proxy.Start() + if err != nil { + log.Fatal(err) + } }