2 files changed, 5 insertions, 5 deletions

diff --git a/src/mailman_pgp/commands/eml_key.py b/src/mailman_pgp/commands/eml_key.py
index e182451..b958b93 100644
--- a/src/mailman_pgp/commands/eml_key.py
+++ b/src/mailman_pgp/commands/eml_key.py
@@ -23,6 +23,7 @@ from mailman.interfaces.command import ContinueProcessing, IEmailCommand
 from mailman.interfaces.pending import IPendings
 from mailman.interfaces.subscriptions import ISubscriptionManager
 from mailman.interfaces.usermanager import IUserManager
+from pgpy.constants import KeyFlags
 from public import public
 from zope.component import getUtility
 from zope.interface import implementer
@@ -77,7 +78,7 @@ def _cmd_set(pgp_list, mlist, msg, msgdata, arguments, results):
               file=results)
         return ContinueProcessing.no
 
-    if not key_usable(key):
+    if not key_usable(key, {KeyFlags.EncryptCommunications, KeyFlags.Sign}):
         print('Need a key which can be used to encrypt communications.',
               file=results)
         return ContinueProcessing.no
@@ -228,7 +229,7 @@ def _cmd_change(pgp_list, mlist, msg, msgdata, arguments, results):
               file=results)
         return ContinueProcessing.no
 
-    if not key_usable(key):
+    if not key_usable(key, {KeyFlags.EncryptCommunications, KeyFlags.Sign}):
         print('Need a key which can be used to encrypt communications.',
               file=results)
         return ContinueProcessing.no
diff --git a/src/mailman_pgp/utils/pgp.py b/src/mailman_pgp/utils/pgp.py
index 1dfdc5e..416e643 100644
--- a/src/mailman_pgp/utils/pgp.py
+++ b/src/mailman_pgp/utils/pgp.py
@@ -107,6 +107,7 @@ def key_usable(key, flags_required):
     :param key:
     :type key: pgpy.PGPKey
     :param flags_required:
+    :type flags_required: set
     :return:
     :rtype: bool
     """
@@ -125,6 +126,4 @@ def key_usable(key, flags_required):
     for subkey in key.subkeys.values():
         usage_flags |= subkey.usage_flags()
 
-    if flags_required not in usage_flags:
-        return False
-    return True
+    return flags_required.issubset(usage_flags)