func (c *DefaultCryptor) Decrypt(decryptor cipher.BlockMode, cipherText []byte) (msg []byte, err error) {
if decryptor != nil {
if len(cipherText) < decryptor.BlockSize() || len(cipherText)%decryptor.BlockSize() != 0 {
err = ErrInputTextSize
return
}
msg = cipherText
decryptor.CryptBlocks(msg, cipherText)
// let caller do pkcs7 unpadding
msg, err = padding.PKCS7.Unpadding(msg, decryptor.BlockSize())
}
return
}
func (c *DefaultCryptor) Encrypt(encryptor cipher.BlockMode, msg []byte) (cipherText []byte, err error) {
if msg != nil {
// let caller do pkcs7 padding
msg = padding.PKCS7.Padding(msg, encryptor.BlockSize())
if len(msg) < encryptor.BlockSize() || len(msg)%encryptor.BlockSize() != 0 {
err = ErrInputTextSize
return
}
cipherText = msg
encryptor.CryptBlocks(cipherText, msg)
}
return
}
// newCipherBlockReader returns an io.Reader that decrypts the given io.Reader using
// the provided block mode cipher.
func newCipherBlockReader(r io.Reader, mode cipher.BlockMode) io.Reader {
cr := &cipherBlockReader{r: r, mode: mode}
cr.outbuf = make([]byte, 0, mode.BlockSize())
cr.inbuf = make([]byte, 0, mode.BlockSize())
return cr
}