Refactor API socket handling

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>

api/server/server.go

@@ -15,11 +15,7 @@ import (
 	"strconv"
 	"strings"
 
-	"crypto/tls"
-	"crypto/x509"
-
 	"code.google.com/p/go.net/websocket"
-	"github.com/docker/libcontainer/user"
 	"github.com/gorilla/mux"
 
 	"github.com/Sirupsen/logrus"
@@ -27,7 +23,6 @@ import (
 	"github.com/docker/docker/api/types"
 	"github.com/docker/docker/daemon/networkdriver/bridge"
 	"github.com/docker/docker/engine"
-	"github.com/docker/docker/pkg/listenbuffer"
 	"github.com/docker/docker/pkg/parsers"
 	"github.com/docker/docker/pkg/stdcopy"
 	"github.com/docker/docker/pkg/streamformatter"
@@ -1409,90 +1404,6 @@ func ServeRequest(eng *engine.Engine, apiversion version.Version, w http.Respons
 	router.ServeHTTP(w, req)
 }
 
-func lookupGidByName(nameOrGid string) (int, error) {
-	groupFile, err := user.GetGroupPath()
-	if err != nil {
-		return -1, err
-	}
-	groups, err := user.ParseGroupFileFilter(groupFile, func(g user.Group) bool {
-		return g.Name == nameOrGid || strconv.Itoa(g.Gid) == nameOrGid
-	})
-	if err != nil {
-		return -1, err
-	}
-	if groups != nil && len(groups) > 0 {
-		return groups[0].Gid, nil
-	}
-	gid, err := strconv.Atoi(nameOrGid)
-	if err == nil {
-		logrus.Warnf("Could not find GID %d", gid)
-		return gid, nil
-	}
-	return -1, fmt.Errorf("Group %s not found", nameOrGid)
-}
-
-func setupTls(cert, key, ca string, l net.Listener) (net.Listener, error) {
-	tlsCert, err := tls.LoadX509KeyPair(cert, key)
-	if err != nil {
-		if os.IsNotExist(err) {
-			return nil, fmt.Errorf("Could not load X509 key pair (%s, %s): %v", cert, key, err)
-		}
-		return nil, fmt.Errorf("Error reading X509 key pair (%s, %s): %q. Make sure the key is encrypted.",
-			cert, key, err)
-	}
-	tlsConfig := &tls.Config{
-		NextProtos:   []string{"http/1.1"},
-		Certificates: []tls.Certificate{tlsCert},
-		// Avoid fallback on insecure SSL protocols
-		MinVersion: tls.VersionTLS10,
-	}
-
-	if ca != "" {
-		certPool := x509.NewCertPool()
-		file, err := ioutil.ReadFile(ca)
-		if err != nil {
-			return nil, fmt.Errorf("Could not read CA certificate: %v", err)
-		}
-		certPool.AppendCertsFromPEM(file)
-		tlsConfig.ClientAuth = tls.RequireAndVerifyClientCert
-		tlsConfig.ClientCAs = certPool
-	}
-
-	return tls.NewListener(l, tlsConfig), nil
-}
-
-func newListener(proto, addr string, bufferRequests bool) (net.Listener, error) {
-	if bufferRequests {
-		return listenbuffer.NewListenBuffer(proto, addr, activationLock)
-	}
-	return net.Listen(proto, addr)
-}
-
-func changeGroup(addr string, nameOrGid string) error {
-	gid, err := lookupGidByName(nameOrGid)
-	if err != nil {
-		return err
-	}
-
-	logrus.Debugf("%s group found. gid: %d", nameOrGid, gid)
-	return os.Chown(addr, 0, gid)
-}
-
-func setSocketGroup(addr, group string) error {
-	if group == "" {
-		return nil
-	}
-
-	if err := changeGroup(addr, group); err != nil {
-		if group != "docker" {
-			return err
-		}
-		logrus.Debugf("Warning: could not chgrp %s to docker: %v", addr, err)
-	}
-
-	return nil
-}
-
 func allocateDaemonPort(addr string) error {
 	host, port, err := net.SplitHostPort(addr)
 	if err != nil {
@@ -1519,35 +1430,6 @@ func allocateDaemonPort(addr string) error {
 	return nil
 }
 
-func setupTcpHttp(addr string, job *engine.Job) (*HttpServer, error) {
-	if !job.GetenvBool("TlsVerify") {
-		logrus.Infof("/!\\ DON'T BIND ON ANY IP ADDRESS WITHOUT setting -tlsverify IF YOU DON'T KNOW WHAT YOU'RE DOING /!\\")
-	}
-
-	r := createRouter(job.Eng, job.GetenvBool("Logging"), job.GetenvBool("EnableCors"), job.Getenv("CorsHeaders"), job.Getenv("Version"))
-
-	l, err := newListener("tcp", addr, job.GetenvBool("BufferRequests"))
-	if err != nil {
-		return nil, err
-	}
-
-	if err := allocateDaemonPort(addr); err != nil {
-		return nil, err
-	}
-
-	if job.GetenvBool("Tls") || job.GetenvBool("TlsVerify") {
-		var tlsCa string
-		if job.GetenvBool("TlsVerify") {
-			tlsCa = job.Getenv("TlsCa")
-		}
-		l, err = setupTls(job.Getenv("TlsCert"), job.Getenv("TlsKey"), tlsCa, l)
-		if err != nil {
-			return nil, err
-		}
-	}
-	return &HttpServer{&http.Server{Addr: addr, Handler: r}, l}, nil
-}
-
 type Server interface {
 	Serve() error
 	Close() error

api/server/server_linux.go

@@ -4,100 +4,86 @@ package server
 
 import (
 	"fmt"
+	"net"
 	"net/http"
-	"os"
-	"syscall"
 
+	"github.com/Sirupsen/logrus"
 	"github.com/docker/docker/engine"
 	"github.com/docker/docker/pkg/systemd"
 )
 
 // NewServer sets up the required Server and does protocol specific checking.
 func NewServer(proto, addr string, job *engine.Job) (Server, error) {
-	// Basic error and sanity checking
+	var (
+		err error
+		l   net.Listener
+		r   = createRouter(
+			job.Eng,
+			job.GetenvBool("Logging"),
+			job.GetenvBool("EnableCors"),
+			job.Getenv("CorsHeaders"),
+			job.Getenv("Version"),
+		)
+	)
 	switch proto {
 	case "fd":
-		return nil, serveFd(addr, job)
+		ls, err := systemd.ListenFD(addr)
+		if err != nil {
+			return nil, err
+		}
+		chErrors := make(chan error, len(ls))
+		// We don't want to start serving on these sockets until the
+		// daemon is initialized and installed. Otherwise required handlers
+		// won't be ready.
+		<-activationLock
+		// Since ListenFD will return one or more sockets we have
+		// to create a go func to spawn off multiple serves
+		for i := range ls {
+			listener := ls[i]
+			go func() {
+				httpSrv := http.Server{Handler: r}
+				chErrors <- httpSrv.Serve(listener)
+			}()
+		}
+		for i := 0; i < len(ls); i++ {
+			if err := <-chErrors; err != nil {
+				return nil, err
+			}
+		}
+		return nil, nil
 	case "tcp":
-		return setupTcpHttp(addr, job)
+		if !job.GetenvBool("TlsVerify") {
+			logrus.Infof("/!\\ DON'T BIND ON ANY IP ADDRESS WITHOUT setting -tlsverify IF YOU DON'T KNOW WHAT YOU'RE DOING /!\\")
+		}
+		if l, err = NewTcpSocket(addr, tlsConfigFromJob(job)); err != nil {
+			return nil, err
+		}
+		if err := allocateDaemonPort(addr); err != nil {
+			return nil, err
+		}
 	case "unix":
-		return setupUnixHttp(addr, job)
-	default:
-		return nil, fmt.Errorf("Invalid protocol format.")
-	}
-}
-
-func setupUnixHttp(addr string, job *engine.Job) (*HttpServer, error) {
-	r := createRouter(job.Eng, job.GetenvBool("Logging"), job.GetenvBool("EnableCors"), job.Getenv("CorsHeaders"), job.Getenv("Version"))
-
-	if err := syscall.Unlink(addr); err != nil && !os.IsNotExist(err) {
-		return nil, err
-	}
-	mask := syscall.Umask(0777)
-	defer syscall.Umask(mask)
-
-	l, err := newListener("unix", addr, job.GetenvBool("BufferRequests"))
-	if err != nil {
-		return nil, err
-	}
-
-	if err := setSocketGroup(addr, job.Getenv("SocketGroup")); err != nil {
-		return nil, err
-	}
-
-	if err := os.Chmod(addr, 0660); err != nil {
-		return nil, err
-	}
-
-	return &HttpServer{&http.Server{Addr: addr, Handler: r}, l}, nil
-}
-
-// serveFd creates an http.Server and sets it up to serve given a socket activated
-// argument.
-func serveFd(addr string, job *engine.Job) error {
-	r := createRouter(job.Eng, job.GetenvBool("Logging"), job.GetenvBool("EnableCors"), job.Getenv("CorsHeaders"), job.Getenv("Version"))
-
-	ls, e := systemd.ListenFD(addr)
-	if e != nil {
-		return e
-	}
-
-	chErrors := make(chan error, len(ls))
-
-	// We don't want to start serving on these sockets until the
-	// daemon is initialized and installed. Otherwise required handlers
-	// won't be ready.
-	<-activationLock
-
-	// Since ListenFD will return one or more sockets we have
-	// to create a go func to spawn off multiple serves
-	for i := range ls {
-		listener := ls[i]
-		go func() {
-			httpSrv := http.Server{Handler: r}
-			chErrors <- httpSrv.Serve(listener)
-		}()
-	}
-
-	for i := 0; i < len(ls); i++ {
-		err := <-chErrors
-		if err != nil {
-			return err
+		if l, err = NewUnixSocket(addr, job.Getenv("SocketGroup")); err != nil {
+			return nil, err
 		}
+	default:
+		return nil, fmt.Errorf("Invalid protocol format: %q", proto)
 	}
-
-	return nil
+	return &HttpServer{
+		&http.Server{
+			Addr:    addr,
+			Handler: r,
+		},
+		l,
+	}, nil
 }
 
 // Called through eng.Job("acceptconnections")
 func AcceptConnections(job *engine.Job) error {
 	// Tell the init daemon we are accepting requests
 	go systemd.SdNotify("READY=1")
-
 	// close the lock so the listeners start accepting connections
 	if activationLock != nil {
 		close(activationLock)
 	}
-
 	return nil
 }

api/server/server_windows.go

@@ -1,19 +1,38 @@
 // +build windows
-
 package server
 
 import (
-	"fmt"
+	"errors"
+	"net"
 
+	"github.com/Sirupsen/logrus"
 	"github.com/docker/docker/engine"
 )
 
 // NewServer sets up the required Server and does protocol specific checking.
 func NewServer(proto, addr string, job *engine.Job) (Server, error) {
-	// Basic error and sanity checking
+	var (
+		err error
+		l   net.Listener
+		r   = createRouter(
+			job.Eng,
+			job.GetenvBool("Logging"),
+			job.GetenvBool("EnableCors"),
+			job.Getenv("CorsHeaders"),
+			job.Getenv("Version"),
+		)
+	)
 	switch proto {
 	case "tcp":
-		return setupTcpHttp(addr, job)
+		if !job.GetenvBool("TlsVerify") {
+			logrus.Infof("/!\\ DON'T BIND ON ANY IP ADDRESS WITHOUT setting -tlsverify IF YOU DON'T KNOW WHAT YOU'RE DOING /!\\")
+		}
+		if l, err = NewTcpSocket(addr, tlsConfigFromJob(job)); err != nil {
+			return nil, err
+		}
+		if err := allocateDaemonPort(addr); err != nil {
+			return nil, err
+		}
 	default:
 		return nil, errors.New("Invalid protocol format. Windows only supports tcp.")
 	}
@@ -21,11 +40,9 @@ func NewServer(proto, addr string, job *engine.Job) (Server, error) {
 
 // Called through eng.Job("acceptconnections")
 func AcceptConnections(job *engine.Job) engine.Status {
-
 	// close the lock so the listeners start accepting connections
 	if activationLock != nil {
 		close(activationLock)
 	}
-
 	return engine.StatusOK
 }

api/server/tcp_socket.go

@@ -0,0 +1,74 @@
+package server
+
+import (
+	"crypto/tls"
+	"crypto/x509"
+	"fmt"
+	"io/ioutil"
+	"net"
+	"os"
+
+	"github.com/docker/docker/engine"
+	"github.com/docker/docker/pkg/listenbuffer"
+)
+
+type tlsConfig struct {
+	CA          string
+	Certificate string
+	Key         string
+	Verify      bool
+}
+
+func tlsConfigFromJob(job *engine.Job) *tlsConfig {
+	verify := job.GetenvBool("TlsVerify")
+	if !job.GetenvBool("Tls") && !verify {
+		return nil
+	}
+	return &tlsConfig{
+		Verify:      verify,
+		Certificate: job.Getenv("TlsCert"),
+		Key:         job.Getenv("TlsKey"),
+		CA:          job.Getenv("TlsCa"),
+	}
+}
+
+func NewTcpSocket(addr string, config *tlsConfig) (net.Listener, error) {
+	l, err := listenbuffer.NewListenBuffer("tcp", addr, activationLock)
+	if err != nil {
+		return nil, err
+	}
+	if config != nil {
+		if l, err = setupTls(l, config); err != nil {
+			return nil, err
+		}
+	}
+	return l, nil
+}
+
+func setupTls(l net.Listener, config *tlsConfig) (net.Listener, error) {
+	tlsCert, err := tls.LoadX509KeyPair(config.Certificate, config.Key)
+	if err != nil {
+		if os.IsNotExist(err) {
+			return nil, fmt.Errorf("Could not load X509 key pair (%s, %s): %v", config.Certificate, config.Key, err)
+		}
+		return nil, fmt.Errorf("Error reading X509 key pair (%s, %s): %q. Make sure the key is encrypted.",
+			config.Certificate, config.Key, err)
+	}
+	tlsConfig := &tls.Config{
+		NextProtos:   []string{"http/1.1"},
+		Certificates: []tls.Certificate{tlsCert},
+		// Avoid fallback on insecure SSL protocols
+		MinVersion: tls.VersionTLS10,
+	}
+	if config.CA != "" {
+		certPool := x509.NewCertPool()
+		file, err := ioutil.ReadFile(config.CA)
+		if err != nil {
+			return nil, fmt.Errorf("Could not read CA certificate: %v", err)
+		}
+		certPool.AppendCertsFromPEM(file)
+		tlsConfig.ClientAuth = tls.RequireAndVerifyClientCert
+		tlsConfig.ClientCAs = certPool
+	}
+	return tls.NewListener(l, tlsConfig), nil
+}

api/server/unix_socket.go

@@ -0,0 +1,78 @@
+package server
+
+import (
+	"fmt"
+	"net"
+	"os"
+	"strconv"
+	"syscall"
+
+	"github.com/Sirupsen/logrus"
+	"github.com/docker/docker/pkg/listenbuffer"
+	"github.com/docker/libcontainer/user"
+)
+
+func NewUnixSocket(path, group string) (net.Listener, error) {
+	if err := syscall.Unlink(path); err != nil && !os.IsNotExist(err) {
+		return nil, err
+	}
+	mask := syscall.Umask(0777)
+	defer syscall.Umask(mask)
+	l, err := listenbuffer.NewListenBuffer("unix", path, activationLock)
+	if err != nil {
+		return nil, err
+	}
+	if err := setSocketGroup(path, group); err != nil {
+		l.Close()
+		return nil, err
+	}
+	if err := os.Chmod(path, 0660); err != nil {
+		l.Close()
+		return nil, err
+	}
+	return l, nil
+}
+
+func setSocketGroup(path, group string) error {
+	if group == "" {
+		return nil
+	}
+	if err := changeGroup(path, group); err != nil {
+		if group != "docker" {
+			return err
+		}
+		logrus.Debugf("Warning: could not change group %s to docker: %v", path, err)
+	}
+	return nil
+}
+
+func changeGroup(path string, nameOrGid string) error {
+	gid, err := lookupGidByName(nameOrGid)
+	if err != nil {
+		return err
+	}
+	logrus.Debugf("%s group found. gid: %d", nameOrGid, gid)
+	return os.Chown(path, 0, gid)
+}
+
+func lookupGidByName(nameOrGid string) (int, error) {
+	groupFile, err := user.GetGroupPath()
+	if err != nil {
+		return -1, err
+	}
+	groups, err := user.ParseGroupFileFilter(groupFile, func(g user.Group) bool {
+		return g.Name == nameOrGid || strconv.Itoa(g.Gid) == nameOrGid
+	})
+	if err != nil {
+		return -1, err
+	}
+	if groups != nil && len(groups) > 0 {
+		return groups[0].Gid, nil
+	}
+	gid, err := strconv.Atoi(nameOrGid)
+	if err == nil {
+		logrus.Warnf("Could not find GID %d", gid)
+		return gid, nil
+	}
+	return -1, fmt.Errorf("Group %s not found", nameOrGid)
+}

docker/daemon.go

@@ -151,7 +151,6 @@ func mainDaemon() {
 	job.Setenv("TlsCa", *flCa)
 	job.Setenv("TlsCert", *flCert)
 	job.Setenv("TlsKey", *flKey)
-	job.SetenvBool("BufferRequests", true)
 
 	// The serve API job never exits unless an error occurs
 	// We need to start it as a goroutine and wait on it so