add AESGCM AEAD support (#3785)
* add AESGCM AEAD support
* remove stray newline
* move AESGCM docs above CCM
diff --git a/docs/hazmat/primitives/symmetric-encryption.rst b/docs/hazmat/primitives/symmetric-encryption.rst
index 7e05acd..9e27540 100644
--- a/docs/hazmat/primitives/symmetric-encryption.rst
+++ b/docs/hazmat/primitives/symmetric-encryption.rst
@@ -294,6 +294,11 @@
.. danger::
+ If you are encrypting data that can fit into memory you should strongly
+ consider using
+ :class:`~cryptography.hazmat.primitives.ciphers.aead.AESGCM` instead
+ of this.
+
When using this mode you **must** not use the decrypted data until
the appropriate finalization method
(:meth:`~cryptography.hazmat.primitives.ciphers.CipherContext.finalize`