Wrap NewGCMWithNonceSize() to enable compilation on Go 1.4

1 files changed, 21 insertions, 0 deletions

diff --git a/cryptfs/gcm_go14.go b/cryptfs/gcm_go14.go
new file mode 100644
index 0000000..4629df3
--- /dev/null
+++ b/cryptfs/gcm_go14.go
@@ -0,0 +1,21 @@
+// +build !go1.5
+
+package cryptfs
+
+import (
+	"fmt"
+	"crypto/cipher"
+)
+
+// 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 {
+		Warn.Printf("128 bit GCM IVs are not supported by Go 1.4 and lower.\n")
+		Warn.Printf("Please use openssl crypto or recompile using a newer Go runtime.\n")
+		return nil, fmt.Errorf("128 bit GCM IVs are not supported by Go 1.4 and lower")
+	}
+	return cipher.NewGCM(bc)
+}