1 files changed, 5 insertions, 3 deletions
diff --git a/src/cryptography/hazmat/backends/openssl/aead.py b/src/cryptography/hazmat/backends/openssl/aead.py
index 5402acb3..9cec3e23 100644
--- a/src/cryptography/hazmat/backends/openssl/aead.py
+++ b/src/cryptography/hazmat/backends/openssl/aead.py
@@ -13,13 +13,15 @@ _DECRYPT = 0
 
 def _aead_cipher_name(cipher):
     from cryptography.hazmat.primitives.ciphers.aead import (
-        AESCCM, ChaCha20Poly1305
+        AESCCM, AESGCM, ChaCha20Poly1305
     )
     if isinstance(cipher, ChaCha20Poly1305):
         return b"chacha20-poly1305"
-    else:
-        assert isinstance(cipher, AESCCM)
+    elif isinstance(cipher, AESCCM):
         return "aes-{0}-ccm".format(len(cipher._key) * 8).encode("ascii")
+    else:
+        assert isinstance(cipher, AESGCM)
+        return "aes-{0}-gcm".format(len(cipher._key) * 8).encode("ascii")
 
 
 def _aead_setup(backend, cipher_name, key, nonce, tag, tag_len, operation):