Re: (ITS#7008) paged results against ldap-proxy errors with 'cookie is invalid'

[whm@stanford.edu]

--On Monday, August 01, 2011 02:46:50 PM -0700 Howard Chu <hyc@symas.com> wrote:

> whm@stanford.edu wrote:
>> Full_Name: Bill MacAllister
>> Version: 2.4.26
>> OS: Debian 6
>> URL: ftp://ftp.openldap.org/incoming/
>> Submission from: (NULL) (171.64.19.165)
>>
>>
>> We typically setup local proxy servers to support applications that cannot
>> support a GSSAPI bind to the directory server.  The proxy server allows
>> anonymous access to the directory for connections from the localhost and
>> connects to the master using GSSAPI.  We are experiencing a failures when
>> we attempt to use the paged results control on the proxy.  For example:
>>
>> ldapsearch -E pr=1000/noprompt -x -b "cn=people,dc=stanford,dc=edu" -h localhost
>>   "(&(objectClass=suPerson)(suVisibIdentity=world))" ou telephonenumber title
>>
>> ends with the error:
>>
>> # search result
>> search: 5
>> result: 0 Success
>> control: 1.2.840.113556.1.4.319 false MA0CAQAECCiDAAAAAAAA
>> pagedresults: cookie=KIMAAAAAAAA=
>> # extended LDIF
>> #
>> # LDAPv3
>> # base<cn=people,dc=stanford,dc=edu>  with scope subtree
>> # filter: (&(objectClass=suPerson)(suVisibIdentity=world))
>> # requesting: ou telephonenumber title
>> # with pagedResults control: size=1000
>> #
>>
>> # search result
>> search: 6
>> result: 2 Protocol error
>> text: paged results cookie is invalid
>>
>> # numResponses: 4005
>> # numEntries: 4000
>>
>> This result is not consistent.  We have seen examples where 2000 and 3000
>> entries being returned and then the error.  Another test that we performed with
>> a slightly more complex filter, i.e.
>>
>>    "(&(objectClass=suPerson)(|(suVisibIdentity=world)(suVisibIdentity=world)))"
>>
>> returned usually returned 1000 entries before erroring.
>>
>> Issuing a similar search directly against the backend ldap server completes
>> without
>> error.
>>
>> We have seen the same behavior on OpenLDAP 2.4.23 as well.
>>
>> Logs generated running slapd standalone with '-d stats,packets' are available at
>> http://www.stanford.edu/~whm/files/ldap-debugging/.
>
> Your log shows that the subsequent search request initiates a new
> Bind to the remote server, which implies that it's not re-using the
> same connection as the first request. Since a paged results cookie
> is only valid within the context of a single connection, you get
> this error result.

Not sure which log you are looking at.  When I look at the log:

http://www.stanford.edu/~whm/files/ldap-debugging/slapd-trace-paged-results.log.gz

The only connection I see in the log is conn=1000 and it ends with:

conn=1000 op=5 SEARCH RESULT tag=101 err=2 nentries=0 text=paged results cookie is invalid
ldap_read: want=8, got=7
  0000:  30 05 02 01 07 42 00                               0....B.
ldap_read: want=8, got=0

conn=1000 op=6 UNBIND
conn=1000 fd=11 closed

These tests where made with a single ldapsearch request.  The ldapsearch
tests fail when using the proxy and succeed when connecting directly to
the LDAP server with the database on it.

A side node: the test case I submitted used ldapsearch, but the
problem was uncovered using a python application that is used for
syncing Gmail account data.

Bill

-- 

Bill MacAllister
Infrastructure Delivery Group, Stanford University