Fix memory leak(2)

shadowsocks/crypto/aead.py

@@ -155,9 +155,6 @@ class AeadCryptoBase(object):
         # n, n > 0, waiting data
         self._chunk = {'mlen': AEAD_MSG_LEN_UNKNOWN, 'data': b''}
 
-        self.encrypt_once = self.aead_encrypt
-        self.decrypt_once = self.aead_decrypt
-
         # load libsodium for nonce increment
         if not sodium_loaded:
             crypto_path = dict(crypto_path) if crypto_path else dict()

shadowsocks/crypto/openssl.py

@@ -270,6 +270,12 @@ class OpenSSLAeadCrypto(OpenSSLCryptoBase, AeadCryptoBase):
         self.cipher_ctx_init()
         return plaintext
 
+    def encrypt_once(self, data):
+        return self.aead_encrypt(data)
+
+    def decrypt_once(self, data):
+        return self.aead_decrypt(data)
+
 
 class OpenSSLStreamCrypto(OpenSSLCryptoBase):
     """

shadowsocks/crypto/sodium.py

@@ -308,6 +308,12 @@ class SodiumAeadCrypto(AeadCryptoBase):
         self.cipher_ctx_init()
         return buf.raw[:cipher_out_len.value]
 
+    def encrypt_once(self, data):
+        return self.aead_encrypt(data)
+
+    def decrypt_once(self, data):
+        return self.aead_decrypt(data)
+
 
 ciphers = {
     'salsa20': (32, 8, SodiumCrypto),