[jcifs] Patch to fix some issues

[Michael B Allen]

On Mon, Aug 1, 2011 at 3:23 PM, Sai Pullabhotla
<sai.pullabhotla at jmethods.com> wrote:
> Thanks Mike, for the clarification and it does make sense.
>
> I ran a wireshark capture with the IBM iSeries shares using Windows
> Explorer on Vista SP2 system and found the following:
>
> The FindFirst and FindNext requests are setting the flag EOS (close if
> end of search), which jcifs does not do, I believe.
>
> The iSeries returns a bad LAST_NAME_OFFSET, which is always zero (this
> was previously mentioned in the mailing list). jcifs in this case
> sends the subsequent FIND_NEXT requests with the first file from the
> previous response instead of the last one. This is the cause for the
> duplicate entries.
>
> Windows however, uses the correct last file that it read from the
> previous response. So, I wonder if we tweak the code to check the
> LAST_NAME_OFFSET and NUMBER_OF_ENTRIES returned and make an
> appropriate decision to send the next request.
>
> Do you think it makes sense to work in this direction?

Hi Sai,

Yes. If you post a patch that makes JCIFS look just like Vista and it
works with iSeries, that will have a high probability of being
integrated and others using iSeries will greatly appreciate it.

Also, if you can, send me a capture of Vista listing iSeries so that I
have it on file (although send any captures to me directly - don't
post captures to the list please).

Mike

-- 
Michael B Allen
Java Active Directory Integration
http://www.ioplex.com/

> On Sat, Jul 30, 2011 at 11:54 AM, Michael B Allen <ioplex at gmail.com> wrote:
>>
>> On Fri, Jul 29, 2011 at 8:56 AM, Sai Pullabhotla
>> <sai.pullabhotla at jmethods.com> wrote:
>> > Just for clarification...
>> >
>> > Are you saying that Windows XP (native windows code) does not set this flag
>> > when connecting to network shares?
>>
>> Hello Sai,
>>
>> Correct. At least the one XP SP2 client that I tested did not use that flag.
>>
>> > If so, does it really matter what XP
>> > does, if JCIFS with the flag set in its requests works with all SMB/CIFS
>> > servers?
>>
>> Yes. It matters. There is no CIFS specification that anyone actually
>> follows. So it is my position that JCIFS should follow the observed
>> behavior of the oldest supported Windows CIFS client (XP SP2). This
>> greatly reduces the possibility that a change in Windows servers could
>> affect JCIFS because Microsoft could not make any such change without
>> affecting the backward compatibility of their own clients. And, what
>> is perhaps more important, the "do as Windows does" rule maximizes
>> compatibility with other non-Microsoft servers because they will also
>> ultimately be writing to Windows clients and using documentation as
>> reference materials.
>>
>> If the XP SP2 TRANS2_FIND_FIRST2 operation works with IBM iSeries
>> servers then someone should find out why and post a patch for that and
>> not just any patch that makes it work.
>>
>> Or if it was shown that Vista used the RESUME_FROM_PREVIOUS_END flag,
>> then we can bend the rule a little since we know it will not be long
>> before it becomes the oldest supported Windows CIFS client. But I have
>> not checked Vista and I do not know if it uses this flag (and I doubt
>> it does).
>>
>> Mike
>>
>> --
>> Michael B Allen
>> Java Active Directory Integration
>> http://www.ioplex.com/
>>
>> >
>> > On Thu, Jul 28, 2011 at 5:34 PM, Michael B Allen <ioplex at gmail.com> wrote:
>> >>
>> >> On Thu, Jul 28, 2011 at 5:47 PM, Sai Pullabhotla
>> >> <sai.pullabhotla at jmethods.com> wrote:
>> >> > Hello,
>> >> >
>> >> > Yesterday I've received an email from some one checking the email list
>> >> > who asked me about if I found a fix for duplicate entries returned
>> >> > when doing the directory listing with IBM i servers. This was
>> >> > discussed on the mailing list before under this thread:
>> >> > http://lists.samba.org/archive/jcifs/2010-December/009462.html.
>> >> >
>> >> > I did fix it as discussed in the mailing list and seems to be working
>> >> > fine with various servers and operating systems. Not only we tested it
>> >> > in house with various systems, but several of our customers are using
>> >> > it successfully with all kinds of operating systems. I thought you
>> >> > might want to consider this patch to be included in the general
>> >> > release, if it looks good to you.
>> >>
>> >> Hello Sai,
>> >>
>> >> Your observations are compelling. However, I looked at this for the
>> >> last release and I found that Windows XP SP2 does NOT set the
>> >> FLAGS_RESUME_FROM_PREVIOUS_END flag. And so I did not make the change.
>> >> Our general rule is that we follow the oldest supported version of
>> >> Windows which is XP SP2.
>> >>
>> >> But I have added your request to the TODO list for further
>> >> consideration (along with your other recommended changes).
>> >>
>> >> Thanks for the feedback,
>> >> Mike
>> >>
>> >> --
>> >> Michael B Allen
>> >> Java Active Directory Integration
>> >> http://www.ioplex.com/
>> >>
>> >> >
>> >> > Attached is the SVN diff made from the 1.3.15 code base. This patch
>> >> > contains a couple of other fixes as well, all are listed below:
>> >> >
>> >> > 1. The duplicate list entries when working with IBM i servers.
>> >> > 2. Debug log setting does not take affect if
>> >> > Config.setProperties(Properties) is used.
>> >> > 3. Added a couple of NT status codes to NTStatus.java to report a nice
>> >> > error messages related to file locking.
>> >> >
>> >> > Hope this gets included in the upcoming release.
>> >> >
>> >> >
>> >> > Sai Pullabhotla
>> >
>> >
>