Implement _fields on AgentKey so __eq__ works correctly

3 files changed, 28 insertions, 1 deletions

diff --git a/paramiko/agent.py b/paramiko/agent.py
index 2171ff71..8486d6ca 100644
--- a/paramiko/agent.py
+++ b/paramiko/agent.py
@@ -475,7 +475,8 @@ class AgentKey(PKey):
 
     @property
     def _fields(self):
-        raise NotImplementedError
+        fallback = [self.get_name(), self.blob]
+        return self.inner_key._fields if self.inner_key else fallback
 
     def sign_ssh_data(self, data, algorithm=None):
         msg = Message()
diff --git a/sites/www/changelog.rst b/sites/www/changelog.rst
index 43f81115..5f085131 100644
--- a/sites/www/changelog.rst
+++ b/sites/www/changelog.rst
@@ -2,6 +2,8 @@
 Changelog
 =========
 
+- :feature:`-` Implement ``_fields()`` on `~paramiko.agent.AgentKey` so that it
+  may be compared (via ``==``) with other `~paramiko.pkey.PKey` instances.
 - :bug:`23 major` Since its inception, Paramiko has (for reasons lost to time)
   implemented authentication as a side effect of handling affirmative replies
   to ``MSG_SERVICE_REQUEST`` protocol messages. What this means is Paramiko
diff --git a/tests/agent.py b/tests/agent.py
new file mode 100644
index 00000000..18ece7a9
--- /dev/null
+++ b/tests/agent.py
@@ -0,0 +1,24 @@
+from paramiko import AgentKey
+
+
+class AgentKey_:
+    class fields:
+        """
+        _fields
+        """
+
+        def defaults_to_get_name_and_blob(self):
+            # Manually construct a 'failed to get inner_key' obj
+            class FallbackAgentKey(AgentKey):
+                def __init__(self, name, blob):
+                    self.name = name
+                    self.blob = blob
+                    self.inner_key = None
+
+            key = FallbackAgentKey(name="lol", blob=b"lmao")
+            assert key._fields == ["lol", b"lmao"]
+
+        def defers_to_inner_key_when_present(self, keys):
+            key = AgentKey(agent=None, blob=keys.pkey.asbytes())
+            assert key._fields == keys.pkey._fields
+            assert key == keys.pkey