Paginating directory contents about pysmb HOT 7 CLOSED

Hi, Vinod.
According to the MS-SMB2 protocol specs, page 314, "<57> Section 2.2.33: Windows-based servers do not support resuming an enumeration at a specified FileIndex. The server will ignore this flag."

In addition, the interpretation of the FileIndex field is not exactly what you have implemented; it does not refer to the entry offset. Instead, the value must be from the FileIndex field in a previous listing response (see MS-FSCC, section 2.4.8). So, you will end up having to enumerate the entire directory listing from the beginning.

Hope this helps you in the debugging.
Michael

from pysmb.

Thanks Michael. The explanation and PDFs were helpful. Seeing as Windows-based servers ignore the flag, I'll hold off on implementing this at the current time and perhaps revisit it in the future.

from pysmb.

Hi Michael. It appears this restriction is no longer in place in the current docs on product behavior: https://docs.microsoft.com/en-us/openspecs/windows_protocols/ms-smb2/a64e55aa-1152-48e4-8206-edd96444e7f7

Does it make sense to implement FileIndex support for enumeration now? I'm curious as to the best approach for this, and whether you had one in mind.

from pysmb.

A server which does not implement enumeration means your client needs to handle all the returned values in one single request-response. This may not be ideal if your client were to run in embedded devices where memory and processing power could be limited.

With that being said, it is not easy to implement an accurate enumeration of a directory as the contents of the directory could be changing rapidly on a busy machine. It is similar to doing a SELECT with LIMIT/OFFSET on a busy database table; the returned rows could be repeated or missed out.

I didn't really do much testing on this enumeration feature, but other services like Samba might choose to implement enumeration.

from pysmb.

That makes sense. The documentation does appear to indicate support for it in some of the newer Windows server versions, and Samba. Do you have plans to add support for this feature to pysmb to allow optional enumeration?

from pysmb.

Currently, pysmb repeats the QUERY_DIRECTORY request again on the same fid until it receives STATUS_NO_MORE_FILES response from the server. Apparently, it achieves the same effect as enumeration.

from pysmb.

Alright; glad to hear.

from pysmb.