From f5f7cbc63f9235ce040687cdf102aeaef69ab422 Mon Sep 17 00:00:00 2001
From: Stanislav Laznicka <slaznick@redhat.com>
Date: Thu, 1 Jun 2017 09:00:15 +0200
Subject: [PATCH] rpc: avoid possible recursion in create_connection
There was a recursion in RPCClient.create_connection() which under rare
circumstances would not have an ending condition. This commit removes
it and cleans up the code a bit as well.
https://pagure.io/freeipa/issue/6796
Reviewed-By: Florence Blanc-Renaud <frenaud@redhat.com>
---
ipalib/rpc.py | 140 +++++++++++++++++++++++++++++++---------------------------
1 file changed, 74 insertions(+), 66 deletions(-)
diff --git a/ipalib/rpc.py b/ipalib/rpc.py
index b12ce4c5365299332587ad0d2990ca30070217bf..e3b8d67d69c084ad1a43390b5f93061826a27e1d 100644
--- a/ipalib/rpc.py
+++ b/ipalib/rpc.py
@@ -999,77 +999,85 @@ class RPCClient(Connectible):
# No session key, do full Kerberos auth
pass
urls = self.get_url_list(rpc_uri)
- serverproxy = None
+
+ proxy_kw = {
+ 'allow_none': True,
+ 'encoding': 'UTF-8',
+ 'verbose': verbose
+ }
+
for url in urls:
- kw = {
- 'allow_none': True,
- 'encoding': 'UTF-8',
- 'verbose': verbose
- }
- if url.startswith('https://'):
- if delegate:
- transport_class = DelegatedKerbTransport
+ # should we get ProtocolError (=> error in HTTP response) and
+ # 401 (=> Unauthorized), we'll be re-trying with new session
+ # cookies several times
+ for _try_num in range(0, 5):
+ if url.startswith('https://'):
+ if delegate:
+ transport_class = DelegatedKerbTransport
+ else:
+ transport_class = KerbTransport
else:
- transport_class = KerbTransport
- else:
- transport_class = LanguageAwareTransport
- kw['transport'] = transport_class(protocol=self.protocol,
- service='HTTP', ccache=ccache)
- self.log.info('trying %s' % url)
- setattr(context, 'request_url', url)
- serverproxy = self.server_proxy_class(url, **kw)
- if len(urls) == 1:
- # if we have only 1 server and then let the
- # main requester handle any errors. This also means it
- # must handle a 401 but we save a ping.
- return serverproxy
- try:
- command = getattr(serverproxy, 'ping')
+ transport_class = LanguageAwareTransport
+ proxy_kw['transport'] = transport_class(
+ protocol=self.protocol, service='HTTP', ccache=ccache)
+ self.log.info('trying %s' % url)
+ setattr(context, 'request_url', url)
+ serverproxy = self.server_proxy_class(url, **proxy_kw)
+ if len(urls) == 1:
+ # if we have only 1 server and then let the
+ # main requester handle any errors. This also means it
+ # must handle a 401 but we save a ping.
+ return serverproxy
try:
- command([], {})
- except Fault as e:
- e = decode_fault(e)
- if e.faultCode in errors_by_code:
- error = errors_by_code[e.faultCode]
- raise error(message=e.faultString)
- else:
- raise UnknownError(
- code=e.faultCode,
- error=e.faultString,
- server=url,
- )
- # We don't care about the response, just that we got one
- break
- except errors.KerberosError:
- # kerberos error on one server is likely on all
- raise
- except ProtocolError as e:
- if hasattr(context, 'session_cookie') and e.errcode == 401:
- # Unauthorized. Remove the session and try again.
- delattr(context, 'session_cookie')
+ command = getattr(serverproxy, 'ping')
try:
- delete_persistent_client_session_data(principal)
- except Exception:
- # This shouldn't happen if we have a session but it isn't fatal.
- pass
- return self.create_connection(
- ccache, verbose, fallback, delegate)
- if not fallback:
+ command([], {})
+ except Fault as e:
+ e = decode_fault(e)
+ if e.faultCode in errors_by_code:
+ error = errors_by_code[e.faultCode]
+ raise error(message=e.faultString)
+ else:
+ raise UnknownError(
+ code=e.faultCode,
+ error=e.faultString,
+ server=url,
+ )
+ # We don't care about the response, just that we got one
+ return serverproxy
+ except errors.KerberosError:
+ # kerberos error on one server is likely on all
raise
- else:
- self.log.info('Connection to %s failed with %s', url, e)
- serverproxy = None
- except Exception as e:
- if not fallback:
- raise
- else:
- self.log.info('Connection to %s failed with %s', url, e)
- serverproxy = None
-
- if serverproxy is None:
- raise NetworkError(uri=_('any of the configured servers'),
- error=', '.join(urls))
- return serverproxy
+ except ProtocolError as e:
+ if hasattr(context, 'session_cookie') and e.errcode == 401:
+ # Unauthorized. Remove the session and try again.
+ delattr(context, 'session_cookie')
+ try:
+ delete_persistent_client_session_data(principal)
+ except Exception:
+ # This shouldn't happen if we have a session but
+ # it isn't fatal.
+ pass
+ # try the same url once more with a new session cookie
+ continue
+ if not fallback:
+ raise
+ else:
+ self.log.info(
+ 'Connection to %s failed with %s', url, e)
+ # try the next url
+ break
+ except Exception as e:
+ if not fallback:
+ raise
+ else:
+ self.log.info(
+ 'Connection to %s failed with %s', url, e)
+ # try the next url
+ break
+ # finished all tries but no serverproxy was found
+ raise NetworkError(uri=_('any of the configured servers'),
+ error=', '.join(urls))
def destroy_connection(self):
conn = getattr(context, self.id, None)
--
2.9.4