feat(CLI): command to list open conns

cmd/localrelay/args.go

@@ -241,6 +241,7 @@ func help() {
 	fmt.Println("  localrelay start")
 	fmt.Println("  localrelay status")
 	fmt.Println("  localrelay monitor")
+	fmt.Println("  localrelay connections")
 	fmt.Println("  localrelay stop")
 	fmt.Println("  localrelay stop <relay>")
 	fmt.Println("  localrelay restart")

cmd/localrelay/conns.go

@@ -0,0 +1,44 @@
+package main
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"time"
+
+	"github.com/containerd/console"
+)
+
+func displayOpenConns() error {
+	// make terminal raw to allow the use of colour on windows terminals
+	current, _ := console.ConsoleFromFile(os.Stdout)
+	// NOTE: Docker healthchecks will panic "provided file is not a console"
+
+	if current != nil {
+		defer current.Reset()
+	}
+
+	if current != nil {
+		if err := current.SetRaw(); err != nil {
+			log.Println(err)
+		}
+	}
+
+	// we don't set terminal to raw here because print statements don't use
+	// carriage returns
+	conns, err := activeConnections()
+	if err != nil {
+
+		fmt.Printf("Daemon:    \x1b[31m [OFFLINE] \x1b[0m\r\n")
+		fmt.Println(err)
+
+		// exit with error
+		os.Exit(1)
+	}
+
+	for _, conn := range conns {
+		fmt.Printf("%s -> %s (%s) (%s)\r\n", conn.RemoteAddr, conn.ForwardedAddr, conn.RelayName, formatDuration(time.Since(time.Unix(conn.Opened, 0))))
+	}
+
+	return nil
+}

cmd/localrelay/daemon.go

@@ -35,3 +35,19 @@ type metrics struct {
 	In, Out, Active, DialAvg  int
 	TotalConns, TotalRequests uint64
 }
+
+type connection struct {
+	ID int64
+
+	LocalAddr  string
+	RemoteAddr string
+	Network    string
+
+	RelayName string
+	RelayHost string
+
+	ForwardedAddr string
+
+	// Opened is a unix timestamp
+	Opened int64
+}

cmd/localrelay/ipc.go

@@ -27,6 +27,7 @@ const (
 	daemonRun uint8 = iota
 	daemonStatus
 	daemonStop
+	daemonConns
 
 	maxErrors = 40
 )
@@ -215,6 +216,36 @@ func ipcLoop(conn io.ReadWriteCloser) error {
 		lenbuf := make([]byte, 2)
 		binary.BigEndian.PutUint16(lenbuf, uint16(respBuf.Len()))
 
+		conn.Write(lenbuf)
+		conn.Write(respBuf.Bytes())
+	case daemonConns:
+		respBuf := bytes.NewBuffer(nil)
+
+		relayConns := make([]connection, 0, 200)
+
+		relays := runningRelaysCopy()
+		for _, r := range relays {
+			for _, conn := range r.GetConns() {
+
+				relayConns = append(relayConns, connection{
+					LocalAddr:  conn.Conn.LocalAddr().String(),
+					RemoteAddr: conn.Conn.RemoteAddr().String(),
+					Network:    conn.Conn.LocalAddr().Network(),
+
+					RelayName:     r.Name,
+					RelayHost:     r.Host,
+					ForwardedAddr: conn.RemoteAddr,
+
+					Opened: conn.Opened.Unix(),
+				})
+			}
+		}
+
+		json.NewEncoder(respBuf).Encode(relayConns)
+
+		lenbuf := make([]byte, 2)
+		binary.BigEndian.PutUint16(lenbuf, uint16(respBuf.Len()))
+
 		conn.Write(lenbuf)
 		conn.Write(respBuf.Bytes())
 	default:

cmd/localrelay/ipcClient.go

@@ -159,3 +159,29 @@ func stopRelay(relayName string) error {
 
 	return nil
 }
+
+func activeConnections() ([]connection, error) {
+	conn, err := IPCConnect()
+	if err != nil {
+		return nil, err
+	}
+
+	defer conn.Close()
+
+	_, err = conn.Write([]byte{0, 3, daemonConns, 0, 0})
+	if err != nil {
+		return nil, err
+	}
+
+	payload, err := readCommand(conn)
+	if err != nil {
+		return nil, err
+	}
+
+	var pool []connection
+	if err := json.Unmarshal(payload, &pool); err != nil {
+		return nil, err
+	}
+
+	return pool, nil
+}

cmd/localrelay/main.go

@@ -3,6 +3,7 @@ package main
 import (
 	"fmt"
 	"log"
+	"os"
 	"strings"
 	"time"
 
@@ -131,6 +132,13 @@ func main() {
 			}
 
 			fmt.Println("Daemon has been started")
+			return
+		case "conns", "connections":
+			if err := displayOpenConns(); err != nil {
+				fmt.Println(err)
+				os.Exit(1)
+			}
+
 			return
 		case "status":
 			if err := relayStatus(); err != nil {

relay.go

@@ -6,6 +6,7 @@ import (
 	"net/http"
 	"strings"
 	"sync"
+	"time"
 
 	"github.com/pkg/errors"
 	"golang.org/x/net/proxy"
@@ -61,7 +62,14 @@ type Relay struct {
 	protocolSwitching map[int]string
 
 	// connPool contains a list of ACTIVE connections
-	connPool []net.Conn
+	connPool []*PooledConn
+}
+
+// PooledConn allows meta data to be attached to a connection
+type PooledConn struct {
+	Conn       net.Conn
+	RemoteAddr string
+	Opened     time.Time
 }
 
 const (
@@ -294,7 +302,7 @@ func (r *Relay) storeConn(conn net.Conn) {
 	r.m.Lock()
 	defer r.m.Unlock()
 
-	r.connPool = append(r.connPool, conn)
+	r.connPool = append(r.connPool, &PooledConn{conn, "", time.Now()})
 }
 
 // popConn removes the provided connection from the conn pool
@@ -303,10 +311,32 @@ func (r *Relay) popConn(conn net.Conn) {
 	defer r.m.Unlock()
 
 	for i := 0; i < len(r.connPool); i++ {
-		if r.connPool[i] == conn {
+		if r.connPool[i].Conn == conn {
 			// remove conn
 			r.connPool = append(r.connPool[:i], r.connPool[i+1:]...)
 			return
 		}
 	}
 }
+
+// setConnRemote will update the conn pool with the remote
+func (r *Relay) setConnRemote(conn net.Conn, remote net.Addr) {
+	r.m.Lock()
+	defer r.m.Unlock()
+
+	for i := 0; i < len(r.connPool); i++ {
+		if r.connPool[i].Conn == conn {
+			// remove conn
+			r.connPool[i].RemoteAddr = remote.String()
+			return
+		}
+	}
+}
+
+// GetConns returns all the active connections to this relay
+func (r *Relay) GetConns() []*PooledConn {
+	r.m.Lock()
+	defer r.m.Unlock()
+
+	return r.connPool
+}

relay_test.go

@@ -63,7 +63,7 @@ func TestConnPool(t *testing.T) {
 					relay.popConn(conn)
 
 					for _, c := range relay.connPool {
-						if c == conn {
+						if c.Conn == conn {
 							t.Fatal("correct conn was not removed")
 						}
 					}

relaytcp.go

@@ -83,6 +83,7 @@ func handleConn(r *Relay, conn net.Conn, network string) {
 			r.Metrics.dial(1, 0, start)
 
 			r.logger.Info.Printf("CONNECTED TO %s\n", r.ForwardAddr)
+			r.setConnRemote(conn, c.RemoteAddr())
 
 			err = streamConns(conn, c, r.Metrics)
 			if err != nil {
@@ -120,6 +121,8 @@ func handleConn(r *Relay, conn net.Conn, network string) {
 	r.Metrics.dial(1, 0, start)
 
 	r.logger.Info.Printf("CONNECTED TO %s\n", r.ForwardAddr)
+	r.setConnRemote(conn, c.RemoteAddr())
+
 	err = streamConns(conn, c, r.Metrics)
 	if err != nil {
 		r.logger.Info.Printf("ERROR FROM %q ON %q: ERR=%s\n", conn.RemoteAddr(), conn.LocalAddr(), err)