Drop Go 1.4 compatability code everywhere

Yields a nice reduction in code size.

19 files changed, 39 insertions, 213 deletions

diff --git a/build.bash b/build.bash
index e492f17..1cc266b 100755
--- a/build.bash
+++ b/build.bash
@@ -38,16 +38,17 @@ BUILDTIME=$(date +%s)
 # Make sure we have the go binary
 go version > /dev/null
 
-# Go 1.5 changed the CLI syntax. Let's also support 1.3 and 1.4.
-# "go version go1.6.2 linux/amd64" -> "1.6"
+# Parse "go version go1.6.2 linux/amd64" to "1.6"
 V=$(go version | cut -d" " -f3 | cut -c3-5)
+# Reject old Go versions already here. It would fail with compile
+# errors anyway.
 if [[ $V == "1.3" || $V == "1.4" ]] ; then
-	LDFLAGS="-X main.GitVersion $GITVERSION -X main.GitVersionFuse $GITVERSIONFUSE -X main.BuildTime $BUILDTIME"
-else
-	# Go 1.5+ wants an "=" here
-	LDFLAGS="-X main.GitVersion=$GITVERSION -X main.GitVersionFuse=$GITVERSIONFUSE -X main.BuildTime=$BUILDTIME"
+	echo "Error: you need Go 1.5 or higher to compile gocryptfs"
+	echo -n "You have: "
+	go version
 fi
 
+LDFLAGS="-X main.GitVersion=$GITVERSION -X main.GitVersionFuse=$GITVERSIONFUSE -X main.BuildTime=$BUILDTIME"
 go build "-ldflags=$LDFLAGS" $@
 
 (cd gocryptfs-xray; go build $@)
diff --git a/internal/cryptocore/cryptocore.go b/internal/cryptocore/cryptocore.go
index fea0c94..735c409 100644
--- a/internal/cryptocore/cryptocore.go
+++ b/internal/cryptocore/cryptocore.go
@@ -74,7 +74,7 @@ func New(key []byte, aeadType AEADTypeEnum, IVBitLen int) *CryptoCore {
 		}
 		aeadCipher = stupidgcm.New(key)
 	case BackendGoGCM:
-		aeadCipher, err = goGCMWrapper(blockCipher, IVLen)
+		aeadCipher, err = cipher.NewGCMWithNonceSize(blockCipher, IVLen)
 	case BackendAESSIV:
 		if IVLen != 16 {
 			// SIV supports any nonce size, but we only use 16.
diff --git a/internal/cryptocore/cryptocore_go1.4_test.go b/internal/cryptocore/cryptocore_go1.4_test.go
deleted file mode 100644
index 14e1e03..0000000
--- a/internal/cryptocore/cryptocore_go1.4_test.go
+++ /dev/null
@@ -1,20 +0,0 @@
-// +build !go1.5
-// = go 1.4 or lower
-
-package cryptocore
-
-import (
-	"testing"
-)
-
-// Native Go crypto with 128-bit IVs is only supported on Go 1.5 and up,
-// this should panic.
-func TestCryptoCoreNewGo14(t *testing.T) {
-	defer func() {
-		if r := recover(); r == nil {
-			t.Errorf("The code did not panic")
-		}
-	}()
-	key := make([]byte, 32)
-	New(key, BackendGoGCM, 128)
-}
diff --git a/internal/cryptocore/cryptocore_go1.5_test.go b/internal/cryptocore/cryptocore_go1.5_test.go
deleted file mode 100644
index f9d38e9..0000000
--- a/internal/cryptocore/cryptocore_go1.5_test.go
+++ /dev/null
@@ -1,16 +0,0 @@
-// +build go1.5
-// = go 1.5 or higher
-
-package cryptocore
-
-import (
-	"testing"
-)
-
-func TestCryptoCoreNewGo15(t *testing.T) {
-	key := make([]byte, 32)
-	c := New(key, BackendGoGCM, 128)
-	if c.IVLen != 16 {
-		t.Fail()
-	}
-}
diff --git a/internal/cryptocore/cryptocore_test.go b/internal/cryptocore/cryptocore_test.go
index c54eac9..252c311 100644
--- a/internal/cryptocore/cryptocore_test.go
+++ b/internal/cryptocore/cryptocore_test.go
@@ -16,7 +16,10 @@ func TestCryptoCoreNew(t *testing.T) {
 	if c.IVLen != 12 {
 		t.Fail()
 	}
-	// "New(key, BackendGoGCM, 128)" is tested for Go 1.4 and 1.5+ separately
+	c = New(key, BackendGoGCM, 128)
+	if c.IVLen != 16 {
+		t.Fail()
+	}
 }
 
 // "New" should panic on any key not 32 bytes long
diff --git a/internal/cryptocore/gcm_go1.4.go b/internal/cryptocore/gcm_go1.4.go
deleted file mode 100644
index c1aa488..0000000
--- a/internal/cryptocore/gcm_go1.4.go
+++ /dev/null
@@ -1,29 +0,0 @@
-// +build !go1.5
-// = go 1.4 or lower
-
-package cryptocore
-
-import (
-	"crypto/cipher"
-	"fmt"
-
-	"github.com/rfjakob/gocryptfs/internal/tlog"
-)
-
-const (
-	// HaveModernGoGCM indicates if Go GCM supports 128-bit nonces
-	HaveModernGoGCM = false
-)
-
-// goGCMWrapper - This wrapper makes sure gocryptfs can be compiled on Go
-// versions 1.4 and lower that lack NewGCMWithNonceSize().
-// 128 bit GCM IVs will not work when using built-in Go crypto, obviously, when
-// compiled on 1.4.
-func goGCMWrapper(bc cipher.Block, nonceSize int) (cipher.AEAD, error) {
-	if nonceSize != 12 {
-		tlog.Warn.Printf("128 bit GCM IVs are not supported by Go 1.4 and lower.")
-		tlog.Warn.Printf("Please use openssl crypto or recompile using a newer Go runtime.")
-		return nil, fmt.Errorf("128 bit GCM IVs are not supported by Go 1.4 and lower")
-	}
-	return cipher.NewGCM(bc)
-}
diff --git a/internal/cryptocore/gcm_go1.5.go b/internal/cryptocore/gcm_go1.5.go
deleted file mode 100644
index 3c38357..0000000
--- a/internal/cryptocore/gcm_go1.5.go
+++ /dev/null
@@ -1,21 +0,0 @@
-// +build go1.5
-// = go 1.5 or higher
-
-package cryptocore
-
-import (
-	"crypto/cipher"
-)
-
-const (
-	// HaveModernGoGCM indicates if Go GCM supports 128-bit nonces
-	HaveModernGoGCM = true
-)
-
-// goGCMWrapper - This wrapper makes sure gocryptfs can be compiled on Go
-// versions 1.4 and lower that lack NewGCMWithNonceSize().
-// 128 bit GCM IVs will not work when using built-in Go crypto, obviously, when
-// compiled on 1.4.
-func goGCMWrapper(bc cipher.Block, nonceSize int) (cipher.AEAD, error) {
-	return cipher.NewGCMWithNonceSize(bc, nonceSize)
-}
diff --git a/internal/nametransform/names.go b/internal/nametransform/names.go
index feec017..83724fb 100644
--- a/internal/nametransform/names.go
+++ b/internal/nametransform/names.go
@@ -24,7 +24,7 @@ type NameTransform struct {
 func New(e *eme.EMECipher, longNames bool, raw64 bool) *NameTransform {
 	b64 := base64.URLEncoding
 	if raw64 {
-		b64 = getRaw64Encoding()
+		b64 = base64.RawURLEncoding
 	}
 	return &NameTransform{
 		emeCipher: e,
diff --git a/internal/nametransform/raw64_go1.4.go b/internal/nametransform/raw64_go1.4.go
deleted file mode 100644
index bbffb69..0000000
--- a/internal/nametransform/raw64_go1.4.go
+++ /dev/null
@@ -1,18 +0,0 @@
-//+build !go1.5
-
-package nametransform
-
-import (
-	"encoding/base64"
-	"log"
-)
-
-const (
-	HaveRaw64 = false
-)
-
-func getRaw64Encoding() *base64.Encoding {
-	log.Panicf("Tried to use base64.RawURLEncoding but your Go version does not provide it.\n" +
-		"You need Go 1.5 or higher.")
-	return nil
-}
diff --git a/internal/nametransform/raw64_go1.5.go b/internal/nametransform/raw64_go1.5.go
deleted file mode 100644
index 1896be3..0000000
--- a/internal/nametransform/raw64_go1.5.go
+++ /dev/null
@@ -1,16 +0,0 @@
-//+build go1.5
-
-package nametransform
-
-import (
-	"encoding/base64"
-)
-
-const (
-	// HaveRaw64 is true when Go is new enough to have base64.RawURLEncoding
-	HaveRaw64 = true
-)
-
-func getRaw64Encoding() *base64.Encoding {
-	return base64.RawURLEncoding
-}
diff --git a/internal/speed/speed.go b/internal/speed/speed.go
index bc829d4..f9bf93c 100644
--- a/internal/speed/speed.go
+++ b/internal/speed/speed.go
@@ -1,5 +1,3 @@
-// +build go1.5
-
 // Package speed implements the "-speed" command-line option,
 // similar to "openssl speed".
 // It benchmarks the crypto algorithms and libraries used by
diff --git a/internal/speed/speed_go1.4.go b/internal/speed/speed_go1.4.go
deleted file mode 100644
index 9c0125c..0000000
--- a/internal/speed/speed_go1.4.go
+++ /dev/null
@@ -1,11 +0,0 @@
-// +build !go1.5
-
-package speed
-
-import (
-	"fmt"
-)
-
-func Run() {
-	fmt.Printf("Compile with Go 1.5 or higher to run the benchmarks\n")
-}
diff --git a/internal/speed/speed_test.go b/internal/speed/speed_test.go
index d6bc187..1e9d859 100644
--- a/internal/speed/speed_test.go
+++ b/internal/speed/speed_test.go
@@ -1,5 +1,3 @@
-// +build go1.5
-
 package speed
 
 /*
diff --git a/internal/stupidgcm/stupidgcm_test.go b/internal/stupidgcm/stupidgcm_test.go
index ba25855..3081085 100644
--- a/internal/stupidgcm/stupidgcm_test.go
+++ b/internal/stupidgcm/stupidgcm_test.go
@@ -1,10 +1,6 @@
-// +build go1.5
-// = go 1.5 or higher
-//
 // We compare against Go's built-in GCM implementation. Since stupidgcm only
 // supports 128-bit IVs and Go only supports that from 1.5 onward, we cannot
 // run these tests on older Go versions.
-
 package stupidgcm
 
 import (
diff --git a/internal/tlog/log.go b/internal/tlog/log.go
index bd8844b..720bb88 100644
--- a/internal/tlog/log.go
+++ b/internal/tlog/log.go
@@ -6,6 +6,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"log"
+	"log/syslog"
 	"os"
 
 	"golang.org/x/crypto/ssh/terminal"
@@ -117,3 +118,27 @@ func init() {
 		postfix: ColorReset,
 	}
 }
+
+// SwitchToSyslog redirects the output of this logger to syslog.
+func (l *toggledLogger) SwitchToSyslog(p syslog.Priority) {
+	w, err := syslog.New(p, ProgramName)
+	if err != nil {
+		Warn.Printf("SwitchToSyslog: %v", err)
+	} else {
+		l.SetOutput(w)
+	}
+}
+
+// SwitchLoggerToSyslog redirects the default log.Logger that the go-fuse lib uses
+// to syslog.
+func SwitchLoggerToSyslog(p syslog.Priority) {
+	w, err := syslog.New(p, ProgramName)
+	if err != nil {
+		Warn.Printf("SwitchLoggerToSyslog: %v", err)
+	} else {
+		log.SetPrefix("go-fuse: ")
+		// Disable printing the timestamp, syslog already provides that
+		log.SetFlags(0)
+		log.SetOutput(w)
+	}
+}
diff --git a/internal/tlog/log_go1.4.go b/internal/tlog/log_go1.4.go
deleted file mode 100644
index 98d69db..0000000
--- a/internal/tlog/log_go1.4.go
+++ /dev/null
@@ -1,16 +0,0 @@
-// +build !go1.5
-// = go 1.4 or lower
-
-package tlog
-
-import (
-	"log/syslog"
-)
-
-func (l *toggledLogger) SwitchToSyslog(p syslog.Priority) {
-	Info.Printf("Cannot switch to syslog - need Go 1.5 or higher")
-}
-
-func SwitchLoggerToSyslog(p syslog.Priority) {
-	Info.Printf("Cannot switch to syslog - need Go 1.5 or higher")
-}
diff --git a/internal/tlog/log_go1.5.go b/internal/tlog/log_go1.5.go
deleted file mode 100644
index 9c152d9..0000000
--- a/internal/tlog/log_go1.5.go
+++ /dev/null
@@ -1,32 +0,0 @@
-// +build go1.5
-// = go 1.5 or higher
-
-package tlog
-
-import (
-	"log"
-	"log/syslog"
-)
-
-func (l *toggledLogger) SwitchToSyslog(p syslog.Priority) {
-	w, err := syslog.New(p, ProgramName)
-	if err != nil {
-		Warn.Printf("SwitchToSyslog: %v", err)
-	} else {
-		l.SetOutput(w)
-	}
-}
-
-// SwitchLoggerToSyslog redirects the default log.Logger that the go-fuse lib uses
-// to syslog.
-func SwitchLoggerToSyslog(p syslog.Priority) {
-	w, err := syslog.New(p, ProgramName)
-	if err != nil {
-		Warn.Printf("SwitchLoggerToSyslog: %v", err)
-	} else {
-		log.SetPrefix("go-fuse: ")
-		// Disable printing the timestamp, syslog already provides that
-		log.SetFlags(0)
-		log.SetOutput(w)
-	}
-}
diff --git a/tests/example_filesystems/example_filesystems_test.go b/tests/example_filesystems/example_filesystems_test.go
index 5192278..a43d2a9 100644
--- a/tests/example_filesystems/example_filesystems_test.go
+++ b/tests/example_filesystems/example_filesystems_test.go
@@ -12,7 +12,6 @@ import (
 	"os"
 	"testing"
 
-	"github.com/rfjakob/gocryptfs/internal/cryptocore"
 	"github.com/rfjakob/gocryptfs/internal/stupidgcm"
 	"github.com/rfjakob/gocryptfs/tests/test_helpers"
 )
@@ -24,12 +23,7 @@ var opensslOpt string
 func TestMain(m *testing.M) {
 	// Make "testing.Verbose()" return the correct value
 	flag.Parse()
-	var variants []string
-	if cryptocore.HaveModernGoGCM {
-		variants = append(variants, "-openssl=false")
-	} else {
-		fmt.Println("Skipping Go GCM tests, Go installation is too old")
-	}
+	variants := []string{"-openssl=false"}
 	if !stupidgcm.BuiltWithoutOpenssl {
 		variants = append(variants, "-openssl=true")
 	} else {
diff --git a/tests/matrix/matrix_test.go b/tests/matrix/matrix_test.go
index 1c5d348..88c255e 100644
--- a/tests/matrix/matrix_test.go
+++ b/tests/matrix/matrix_test.go
@@ -23,8 +23,6 @@ import (
 	"syscall"
 	"testing"
 
-	"github.com/rfjakob/gocryptfs/internal/cryptocore"
-	"github.com/rfjakob/gocryptfs/internal/nametransform"
 	"github.com/rfjakob/gocryptfs/internal/syscallcompat"
 	"github.com/rfjakob/gocryptfs/tests/test_helpers"
 )
@@ -60,14 +58,6 @@ func TestMain(m *testing.M) {
 	// Make "testing.Verbose()" return the correct value
 	flag.Parse()
 	for _, testcase = range matrix {
-		if !cryptocore.HaveModernGoGCM && testcase.openssl != "true" {
-			fmt.Printf("Skipping Go GCM variant, Go installation is too old")
-			continue
-		}
-		if testcase.raw64 && !nametransform.HaveRaw64 {
-			fmt.Printf("Skipping raw64 test, Go installation is too old")
-			continue
-		}
 		if testing.Verbose() {
 			fmt.Printf("matrix: testcase = %#v\n", testcase)
 		}