1 // Copyright 2009 The Go Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style
3 // license that can be found in the LICENSE file.
12 // The AES block size in bytes.
15 // A cipher is an instance of AES encryption using a particular key.
16 type aesCipher struct {
23 func (k KeySizeError) Error() string {
24 return "crypto/aes: invalid key size " + strconv.Itoa(int(k))
27 // NewCipher creates and returns a new cipher.Block.
28 // The key argument should be the AES key,
29 // either 16, 24, or 32 bytes to select
30 // AES-128, AES-192, or AES-256.
31 func NewCipher(key []byte) (cipher.Block, error) {
35 return nil, KeySizeError(k)
41 c := &aesCipher{make([]uint32, n), make([]uint32, n)}
42 expandKey(key, c.enc, c.dec)
46 func (c *aesCipher) BlockSize() int { return BlockSize }
48 func (c *aesCipher) Encrypt(dst, src []byte) { encryptBlock(c.enc, dst, src) }
50 func (c *aesCipher) Decrypt(dst, src []byte) { decryptBlock(c.dec, dst, src) }