Fix NameError in PQDH when handling invalid algorithms

Author: RinZ27

asyncssh/crypto/pq.py

@@ -59,7 +59,7 @@ def __init__(self, alg_name: bytes):
             self.ciphertext_bytes, self.secret_bytes, \
             oqs_name = _pq_algs[alg_name]
         except KeyError: # pragma: no cover, other algs not registered
-            raise ValueError(f'Unknown PQ algorithm {oqs_name}') from None
+            raise ValueError(f'Unknown PQ algorithm {alg_name.decode()}') from None
 
         if not hasattr(_oqs, 'OQS_' + oqs_name + '_keypair'): # pragma: no cover
             oqs_name += '_ipd'

tests/test_kex.py

@@ -650,3 +650,9 @@ async def test_rsa_errors(self):
 
         client_conn.close()
         server_conn.close()
+
+    def test_invalid_pq_alg(self):
+        """Test providing an invalid PQ algorithm"""
+
+        with self.assertRaisesRegex(ValueError, 'Unknown PQ algorithm invalid'):
+            PQDH(b'invalid')