Refactor HostKeys' scan-for-entry code

1 files changed, 18 insertions, 8 deletions

diff --git a/paramiko/hostkeys.py b/paramiko/hostkeys.py
index f5c622ed..4be3fd42 100644
--- a/paramiko/hostkeys.py
+++ b/paramiko/hostkeys.py
@@ -186,18 +186,28 @@ class HostKeys (MutableMapping):
 
         entries = []
         for e in self._entries:
-            for h in e.hostnames:
-                if (
-                    h == hostname or
-                    h.startswith('|1|') and
-                    not hostname.startswith('|1|') and
-                    constant_time_bytes_eq(self.hash_host(hostname, h), h)
-                ):
-                    entries.append(e)
+            if self._hostname_matches(hostname, e):
+                entries.append(e)
         if len(entries) == 0:
             return None
         return SubDict(hostname, entries, self)
 
+    def _hostname_matches(self, hostname, entry):
+        """
+        Tests whether ``hostname`` string matches given SubDict ``entry``.
+
+        :returns bool:
+        """
+        for h in entry.hostnames:
+            if (
+                h == hostname or
+                h.startswith('|1|') and
+                not hostname.startswith('|1|') and
+                constant_time_bytes_eq(self.hash_host(hostname, h), h)
+            ):
+                return True
+        return False
+
     def check(self, hostname, key):
         """
         Return True if the given key is associated with the given hostname