1 files changed, 42 insertions, 0 deletions
diff --git a/backend.go b/backend.go
new file mode 100644
index 0000000..ad80b9a
--- /dev/null
+++ b/backend.go
@@ -0,0 +1,42 @@
+package gocryptfs
+
+import (
+	"crypto/cipher"
+	"crypto/aes"
+)
+
+const (
+	NONCE_LEN = 12
+	AUTH_TAG_LEN = 16
+	DEFAULT_PLAINBS = 4096
+
+	ENCRYPT = true
+	DECRYPT = false
+)
+
+type Backend struct {
+	blockCipher cipher.Block
+	gcm cipher.AEAD
+	plainBS	int64
+	cipherBS int64
+}
+
+func New(key [16]byte) *Backend {
+
+	b, err := aes.NewCipher(key[:])
+	if err != nil {
+		panic(err)
+	}
+
+	g, err := cipher.NewGCM(b)
+	if err != nil {
+		panic(err)
+	}
+
+	return &Backend{
+		blockCipher: b,
+		gcm: g,
+		plainBS: DEFAULT_PLAINBS,
+		cipherBS: DEFAULT_PLAINBS + NONCE_LEN + AUTH_TAG_LEN,
+	}
+}