Created app package, and better TLS compatibility with HTTP/2

app/app.go

+// Package app holds application-global state to make it accessible
+// by other packages in the application.
+//
+// This package differs from config in that the things in app aren't
+// really related to server configuration.
+package app
+
+import (
+	"errors"
+	"runtime"
+	"strconv"
+	"strings"
+	"sync"
+
+	"github.com/mholt/caddy/server"
+)
+
+const (
+	// Program name
+	Name = "Caddy"
+
+	// Program version
+	Version = "0.6.0"
+)
+
+var (
+	// Servers is a list of all the currently-listening servers
+	Servers []*server.Server
+
+	// This mutex protects the Servers slice during changes
+	ServersMutex sync.Mutex
+
+	// Waiting on Wg will block until all listeners have shut down.
+	Wg sync.WaitGroup
+
+	// Whether HTTP2 is enabled or not
+	Http2 bool // TODO: temporary flag until http2 is standard
+
+	// Quiet mode hides non-error initialization output
+	Quiet bool
+)
+
+// SetCPU parses string cpu and sets GOMAXPROCS
+// according to its value. It accepts either
+// a number (e.g. 3) or a percent (e.g. 50%).
+func SetCPU(cpu string) error {
+	var numCPU int
+
+	availCPU := runtime.NumCPU()
+
+	if strings.HasSuffix(cpu, "%") {
+		// Percent
+		var percent float32
+		pctStr := cpu[:len(cpu)-1]
+		pctInt, err := strconv.Atoi(pctStr)
+		if err != nil || pctInt < 1 || pctInt > 100 {
+			return errors.New("Invalid CPU value: percentage must be between 1-100")
+		}
+		percent = float32(pctInt) / 100
+		numCPU = int(float32(availCPU) * percent)
+	} else {
+		// Number
+		num, err := strconv.Atoi(cpu)
+		if err != nil || num < 1 {
+			return errors.New("Invalid CPU value: provide a number or percent greater than 0")
+		}
+		numCPU = num
+	}
+
+	if numCPU > availCPU {
+		numCPU = availCPU
+	}
+
+	runtime.GOMAXPROCS(numCPU)
+	return nil
+}

config/config.go

 package config
 
 import (
+	"errors"
+	"fmt"
 	"io"
 	"log"
+	"net"
 
+	"github.com/mholt/caddy/app"
 	"github.com/mholt/caddy/config/parse"
 	"github.com/mholt/caddy/config/setup"
 	"github.com/mholt/caddy/middleware"
@@ -41,8 +45,8 @@ func Load(filename string, input io.Reader) ([]server.Config, error) {
 			Root:       Root,
 			Middleware: make(map[string][]middleware.Middleware),
 			ConfigFile: filename,
-			AppName:    AppName,
-			AppVersion: AppVersion,
+			AppName:    app.Name,
+			AppVersion: app.Version,
 		}
 
 		// It is crucial that directives are executed in the proper order.
@@ -81,6 +85,46 @@ func Load(filename string, input io.Reader) ([]server.Config, error) {
 	return configs, nil
 }
 
+// ArrangeBindings groups configurations by their bind address. For example,
+// a server that should listen on localhost and another on 127.0.0.1 will
+// be grouped into the same address: 127.0.0.1. It will return an error
+// if the address lookup fails or if a TLS listener is configured on the
+// same address as a plaintext HTTP listener. The return value is a map of
+// bind address to list of configs that would become VirtualHosts on that
+// server.
+func ArrangeBindings(allConfigs []server.Config) (map[*net.TCPAddr][]server.Config, error) {
+	addresses := make(map[*net.TCPAddr][]server.Config)
+
+	// Group configs by bind address
+	for _, conf := range allConfigs {
+		addr, err := net.ResolveTCPAddr("tcp", conf.Address())
+		if err != nil {
+			return addresses, errors.New("Could not serve " + conf.Address() + " - " + err.Error())
+		}
+		addresses[addr] = append(addresses[addr], conf)
+	}
+
+	// Don't allow HTTP and HTTPS to be served on the same address
+	for _, configs := range addresses {
+		isTLS := configs[0].TLS.Enabled
+		for _, config := range configs {
+			if config.TLS.Enabled != isTLS {
+				thisConfigProto, otherConfigProto := "HTTP", "HTTP"
+				if config.TLS.Enabled {
+					thisConfigProto = "HTTPS"
+				}
+				if configs[0].TLS.Enabled {
+					otherConfigProto = "HTTPS"
+				}
+				return addresses, fmt.Errorf("Configuration error: Cannot multiplex %s (%s) and %s (%s) on same address",
+					configs[0].Address(), otherConfigProto, config.Address(), thisConfigProto)
+			}
+		}
+	}
+
+	return addresses, nil
+}
+
 // validDirective returns true if d is a valid
 // directive; false otherwise.
 func validDirective(d string) bool {
@@ -109,7 +153,3 @@ var (
 	Host = DefaultHost
 	Port = DefaultPort
 )
-
-// The application should set these so that various middlewares
-// can access the proper information for their own needs.
-var AppName, AppVersion string

config/setup/tls.go

@@ -6,33 +6,10 @@ import (
 	"strconv"
 	"strings"
 
+	"github.com/mholt/caddy/app"
 	"github.com/mholt/caddy/middleware"
 )
 
-// Map of supported protocols
-// SSLv3 will be not supported in next release
-var supportedProtocols = map[string]uint16{
-	"ssl3.0": tls.VersionSSL30,
-	"tls1.0": tls.VersionTLS10,
-	"tls1.1": tls.VersionTLS11,
-	"tls1.2": tls.VersionTLS12,
-}
-
-// Map of supported ciphers
-// For security reasons caddy will not support RC4 ciphers
-var supportedCiphers = map[string]uint16{
-	"ECDHE-RSA-AES128-GCM-SHA256":   tls.TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
-	"ECDHE-ECDSA-AES128-GCM-SHA256": tls.TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256,
-	"ECDHE-RSA-AES128-CBC-SHA":      tls.TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,
-	"ECDHE-RSA-AES256-CBC-SHA":      tls.TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA,
-	"ECDHE-ECDSA-AES256-CBC-SHA":    tls.TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA,
-	"ECDHE-ECDSA-AES128-CBC-SHA":    tls.TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA,
-	"RSA-AES128-CBC-SHA":            tls.TLS_RSA_WITH_AES_128_CBC_SHA,
-	"RSA-AES256-CBC-SHA":            tls.TLS_RSA_WITH_AES_256_CBC_SHA,
-	"ECDHE-RSA-3DES-EDE-CBC-SHA":    tls.TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA,
-	"RSA-3DES-EDE-CBC-SHA":          tls.TLS_RSA_WITH_3DES_EDE_CBC_SHA,
-}
-
 func TLS(c *Controller) (middleware.Middleware, error) {
 	c.TLS.Enabled = true
 	if c.Port == "http" {
@@ -79,6 +56,9 @@ func TLS(c *Controller) (middleware.Middleware, error) {
 					if !ok {
 						return nil, c.Errf("Wrong cipher name or cipher not supported '%s'", c.Val())
 					}
+					if _, ok := http2CipherSuites[value]; app.Http2 && !ok {
+						return nil, c.Errf("Cipher suite %s is not allowed for HTTP/2", c.Val())
+					}
 					c.TLS.Ciphers = append(c.TLS.Ciphers, value)
 				}
 			case "cache":
@@ -87,7 +67,7 @@ func TLS(c *Controller) (middleware.Middleware, error) {
 				}
 				size, err := strconv.Atoi(c.Val())
 				if err != nil {
-					return nil, c.Errf("Cache parameter should be an number '%s': %v", c.Val(), err)
+					return nil, c.Errf("Cache parameter must be an number '%s': %v", c.Val(), err)
 				}
 				c.TLS.CacheSize = size
 			default:
@@ -96,12 +76,14 @@ func TLS(c *Controller) (middleware.Middleware, error) {
 		}
 	}
 
-	// If no Ciphers provided, use all caddy supportedCiphers
+	// If no ciphers provided, use all that Caddy supports for the protocol
 	if len(c.TLS.Ciphers) == 0 {
 		for _, v := range supportedCiphers {
+			if _, ok := http2CipherSuites[v]; !app.Http2 || ok {
 				c.TLS.Ciphers = append(c.TLS.Ciphers, v)
 			}
 		}
+	}
 
 	// If no ProtocolMin provided, set default MinVersion to TLSv1.1 for security reasons
 	if c.TLS.ProtocolMinVersion == 0 {
@@ -114,9 +96,43 @@ func TLS(c *Controller) (middleware.Middleware, error) {
 	}
 
 	//If no cachesize provided, set default to 64
-	if c.TLS.CacheSize == 0 {
+	if c.TLS.CacheSize <= 0 {
 		c.TLS.CacheSize = 64
 	}
 
 	return nil, nil
 }
+
+// Map of supported protocols
+// SSLv3 will be not supported in next release
+// HTTP/2 only supports TLS 1.2 and higher
+var supportedProtocols = map[string]uint16{
+	"ssl3.0": tls.VersionSSL30,
+	"tls1.0": tls.VersionTLS10,
+	"tls1.1": tls.VersionTLS11,
+	"tls1.2": tls.VersionTLS12,
+}
+
+// Map of supported ciphers.
+//
+// Note that, at time of writing, HTTP/2 blacklists 276 cipher suites,
+// including all but two of the suites below (the two GCM suites).
+var supportedCiphers = map[string]uint16{
+	"ECDHE-RSA-AES128-GCM-SHA256":   tls.TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
+	"ECDHE-ECDSA-AES128-GCM-SHA256": tls.TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256,
+	"ECDHE-RSA-AES128-CBC-SHA":      tls.TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,
+	"ECDHE-RSA-AES256-CBC-SHA":      tls.TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA,
+	"ECDHE-ECDSA-AES256-CBC-SHA":    tls.TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA,
+	"ECDHE-ECDSA-AES128-CBC-SHA":    tls.TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA,
+	"RSA-AES128-CBC-SHA":            tls.TLS_RSA_WITH_AES_128_CBC_SHA,
+	"RSA-AES256-CBC-SHA":            tls.TLS_RSA_WITH_AES_256_CBC_SHA,
+	"ECDHE-RSA-3DES-EDE-CBC-SHA":    tls.TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA,
+	"RSA-3DES-EDE-CBC-SHA":          tls.TLS_RSA_WITH_3DES_EDE_CBC_SHA,
+}
+
+// Set of cipher suites not blacklisted by HTTP/2 spec.
+// See https://http2.github.io/http2-spec/#BadCipherSuites
+var http2CipherSuites = map[uint16]struct{}{
+	tls.TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256:   struct{}{},
+	tls.TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256: struct{}{},
+}

config/setup/tls_test.go

@@ -3,8 +3,29 @@ package setup
 import (
 	"crypto/tls"
 	"testing"
+
+	"github.com/mholt/caddy/app"
 )
 
+func TestTLSParseBasic(t *testing.T) {
+	c := newTestController(`tls cert.pem key.pem`)
+
+	_, err := TLS(c)
+	if err != nil {
+		t.Error("Expected no errors, but had an error")
+	}
+
+	if c.TLS.Certificate != "cert.pem" {
+		t.Errorf("Expected certificate arg to be 'cert.pem', was '%s'", c.TLS.Certificate)
+	}
+	if c.TLS.Key != "key.pem" {
+		t.Errorf("Expected key arg to be 'key.pem', was '%s'", c.TLS.Key)
+	}
+	if !c.TLS.Enabled {
+		t.Error("Expected TLS Enabled=true, but was false")
+	}
+}
+
 func TestTLSParseNoOptional(t *testing.T) {
 	c := newTestController(`tls cert.crt cert.key`)
 
@@ -44,7 +65,6 @@ func TestTLSParseIncompleteParams(t *testing.T) {
 	if err == nil {
 		t.Errorf("Expected errors, but no error returned")
 	}
-
 }
 
 func TestTLSParseWithOptionalParams(t *testing.T) {
@@ -107,3 +127,43 @@ func TestTLSParseWithWrongOptionalParams(t *testing.T) {
 		t.Errorf("Expected errors, but no error returned")
 	}
 }
+
+func TestTLSParseWithHTTP2Requirements(t *testing.T) {
+	params := `tls cert.crt cert.key`
+	c := newTestController(params)
+
+	// With HTTP2, cipher suites should be limited
+	app.Http2 = true
+	_, err := TLS(c)
+	if err != nil {
+		t.Errorf("Expected no errors, got: %v", err)
+	}
+	if len(c.TLS.Ciphers) != len(http2CipherSuites) {
+		t.Errorf("With HTTP/2 on, expected %d supported ciphers, got %d",
+			len(http2CipherSuites), len(c.TLS.Ciphers))
+	}
+
+	params = `tls cert.crt cert.key {
+			ciphers RSA-AES128-CBC-SHA
+		}`
+	c = newTestController(params)
+	// Should not be able to specify a blacklisted cipher suite with HTTP2 on
+	_, err = TLS(c)
+	if err == nil {
+		t.Error("Expected an error because cipher suite is invalid for HTTP/2")
+	}
+
+	params = `tls cert.crt cert.key`
+	c = newTestController(params)
+
+	// Without HTTP2, cipher suites should not be as restricted
+	app.Http2 = false
+	_, err = TLS(c)
+	if err != nil {
+		t.Errorf("Expected no errors, got: %v", err)
+	}
+	if len(c.TLS.Ciphers) != len(supportedCiphers) {
+		t.Errorf("With HTTP/2 off, expected %d supported ciphers, got %d",
+			len(supportedCiphers), len(c.TLS.Ciphers))
+	}
+}

main.go

@@ -2,58 +2,49 @@ package main
 
 import (
 	"bytes"
-	"errors"
 	"flag"
 	"fmt"
 	"io/ioutil"
 	"log"
-	"net"
 	"os"
 	"os/exec"
 	"path"
 	"runtime"
 	"strconv"
 	"strings"
-	"sync"
 
+	"github.com/mholt/caddy/app"
 	"github.com/mholt/caddy/config"
 	"github.com/mholt/caddy/server"
 )
 
 var (
 	conf    string
-	http2   bool // TODO: temporary flag until http2 is standard
-	quiet   bool
 	cpu     string
 	version bool
 )
 
 func init() {
 	flag.StringVar(&conf, "conf", "", "Configuration file to use (default="+config.DefaultConfigFile+")")
-	flag.BoolVar(&http2, "http2", true, "Enable HTTP/2 support") // TODO: temporary flag until http2 merged into std lib
-	flag.BoolVar(&quiet, "quiet", false, "Quiet mode (no initialization output)")
+	flag.BoolVar(&app.Http2, "http2", true, "Enable HTTP/2 support") // TODO: temporary flag until http2 merged into std lib
+	flag.BoolVar(&app.Quiet, "quiet", false, "Quiet mode (no initialization output)")
 	flag.StringVar(&cpu, "cpu", "100%", "CPU cap")
 	flag.StringVar(&config.Root, "root", config.DefaultRoot, "Root path to default site")
 	flag.StringVar(&config.Host, "host", config.DefaultHost, "Default host")
 	flag.StringVar(&config.Port, "port", config.DefaultPort, "Default port")
 	flag.BoolVar(&version, "version", false, "Show version")
-
-	config.AppName = "Caddy"
-	config.AppVersion = "0.6.0"
 }
 
 func main() {
 	flag.Parse()
 
 	if version {
-		fmt.Printf("%s %s\n", config.AppName, config.AppVersion)
+		fmt.Printf("%s %s\n", app.Name, app.Version)
 		os.Exit(0)
 	}
 
-	var wg sync.WaitGroup
-
 	// Set CPU cap
-	err := setCPU(cpu)
+	err := app.SetCPU(cpu)
 	if err != nil {
 		log.Fatal(err)
 	}
@@ -65,7 +56,7 @@ func main() {
 	}
 
 	// Group by address (virtual hosts)
-	addresses, err := arrangeBindings(allConfigs)
+	addresses, err := config.ArrangeBindings(allConfigs)
 	if err != nil {
 		log.Fatal(err)
 	}
@@ -76,18 +67,21 @@ func main() {
 		if err != nil {
 			log.Fatal(err)
 		}
-		s.HTTP2 = http2 // TODO: This setting is temporary
-		wg.Add(1)
+		s.HTTP2 = app.Http2 // TODO: This setting is temporary
+		app.Wg.Add(1)
 		go func(s *server.Server) {
-			defer wg.Done()
+			defer app.Wg.Done()
 			err := s.Serve()
 			if err != nil {
 				log.Fatal(err) // kill whole process to avoid a half-alive zombie server
 			}
 		}(s)
 
-		if !quiet {
+		app.Servers = append(app.Servers, s)
+
+		if !app.Quiet {
 			var checkedFdLimit bool
+
 			for addr, configs := range addresses {
 				for _, conf := range configs {
 					// Print address of site
@@ -117,7 +111,7 @@ func main() {
 		}
 	}
 
-	wg.Wait()
+	app.Wg.Wait()
 }
 
 func isLocalhost(s string) bool {
@@ -169,76 +163,3 @@ func loadConfigs() ([]server.Config, error) {
 
 	return config.Load(config.DefaultConfigFile, file)
 }
-
-// arrangeBindings groups configurations by their bind address. For example,
-// a server that should listen on localhost and another on 127.0.0.1 will
-// be grouped into the same address: 127.0.0.1. It will return an error
-// if the address lookup fails or if a TLS listener is configured on the
-// same address as a plaintext HTTP listener.
-func arrangeBindings(allConfigs []server.Config) (map[*net.TCPAddr][]server.Config, error) {
-	addresses := make(map[*net.TCPAddr][]server.Config)
-
-	// Group configs by bind address
-	for _, conf := range allConfigs {
-		addr, err := net.ResolveTCPAddr("tcp", conf.Address())
-		if err != nil {
-			return addresses, errors.New("Could not serve " + conf.Address() + " - " + err.Error())
-		}
-		addresses[addr] = append(addresses[addr], conf)
-	}
-
-	// Don't allow HTTP and HTTPS to be served on the same address
-	for _, configs := range addresses {
-		isTLS := configs[0].TLS.Enabled
-		for _, config := range configs {
-			if config.TLS.Enabled != isTLS {
-				thisConfigProto, otherConfigProto := "HTTP", "HTTP"
-				if config.TLS.Enabled {
-					thisConfigProto = "HTTPS"
-				}
-				if configs[0].TLS.Enabled {
-					otherConfigProto = "HTTPS"
-				}
-				return addresses, fmt.Errorf("Configuration error: Cannot multiplex %s (%s) and %s (%s) on same address",
-					configs[0].Address(), otherConfigProto, config.Address(), thisConfigProto)
-			}
-		}
-	}
-
-	return addresses, nil
-}
-
-// setCPU parses string cpu and sets GOMAXPROCS
-// according to its value. It accepts either
-// a number (e.g. 3) or a percent (e.g. 50%).
-func setCPU(cpu string) error {
-	var numCPU int
-
-	availCPU := runtime.NumCPU()
-
-	if strings.HasSuffix(cpu, "%") {
-		// Percent
-		var percent float32
-		pctStr := cpu[:len(cpu)-1]
-		pctInt, err := strconv.Atoi(pctStr)
-		if err != nil || pctInt < 1 || pctInt > 100 {
-			return errors.New("Invalid CPU value: percentage must be between 1-100")
-		}
-		percent = float32(pctInt) / 100
-		numCPU = int(float32(availCPU) * percent)
-	} else {
-		// Number
-		num, err := strconv.Atoi(cpu)
-		if err != nil || num < 1 {
-			return errors.New("Invalid CPU value: provide a number or percent greater than 0")
-		}
-		numCPU = num
-	}
-
-	if numCPU > availCPU {
-		numCPU = availCPU
-	}
-
-	runtime.GOMAXPROCS(numCPU)
-	return nil
-}

server/server.go

@@ -132,17 +132,11 @@ func ListenAndServeTLSWithSNI(srv *http.Server, tlsConfigs []TLSConfig) error {
 	}
 	config.BuildNameToCertificate()
 
-	// Here we change some crypto/tls defaults based on caddyfile
-	// If no config provided, we set defaults focused in security
-
-	// Add a session cache LRU algorithm
+	// Customize our TLS configuration
 	config.ClientSessionCache = tls.NewLRUClientSessionCache(tlsConfigs[0].CacheSize)
-
 	config.MinVersion = tlsConfigs[0].ProtocolMinVersion
 	config.MaxVersion = tlsConfigs[0].ProtocolMaxVersion
 	config.CipherSuites = tlsConfigs[0].Ciphers
-
-	// Server ciphers have priority over client ciphers
 	config.PreferServerCipherSuites = true
 
 	conn, err := net.Listen("tcp", addr)