v1.0.0

common/crypto/aes.go

@@ -0,0 +1,40 @@
+package crypto
+
+import (
+	"crypto/aes"
+	"crypto/cipher"
+
+	"github.com/xtls/xray-core/v1/common"
+)
+
+// NewAesDecryptionStream creates a new AES encryption stream based on given key and IV.
+// Caller must ensure the length of key and IV is either 16, 24 or 32 bytes.
+func NewAesDecryptionStream(key []byte, iv []byte) cipher.Stream {
+	return NewAesStreamMethod(key, iv, cipher.NewCFBDecrypter)
+}
+
+// NewAesEncryptionStream creates a new AES description stream based on given key and IV.
+// Caller must ensure the length of key and IV is either 16, 24 or 32 bytes.
+func NewAesEncryptionStream(key []byte, iv []byte) cipher.Stream {
+	return NewAesStreamMethod(key, iv, cipher.NewCFBEncrypter)
+}
+
+func NewAesStreamMethod(key []byte, iv []byte, f func(cipher.Block, []byte) cipher.Stream) cipher.Stream {
+	aesBlock, err := aes.NewCipher(key)
+	common.Must(err)
+	return f(aesBlock, iv)
+}
+
+// NewAesCTRStream creates a stream cipher based on AES-CTR.
+func NewAesCTRStream(key []byte, iv []byte) cipher.Stream {
+	return NewAesStreamMethod(key, iv, cipher.NewCTR)
+}
+
+// NewAesGcm creates a AEAD cipher based on AES-GCM.
+func NewAesGcm(key []byte) cipher.AEAD {
+	block, err := aes.NewCipher(key)
+	common.Must(err)
+	aead, err := cipher.NewGCM(block)
+	common.Must(err)
+	return aead
+}