|Version 1.39 November 30, 2005
|A Partial List of Missing Features
|Contributions are welcome. There are plenty of opportunities
|for visible, important contributions to this module. Here
|is a partial list of the known problems and missing features:
|a) Support for SecurityDescriptors(Windows/CIFS ACLs) for chmod/chgrp/chown
|so that these operations can be supported to Windows servers
|b) Mapping POSIX ACLs (and eventually NFSv4 ACLs) to CIFS
|c) Better pam/winbind integration (e.g. to handle uid mapping
|d) Kerberos/SPNEGO session setup support - (started)
|e) NTLMv2 authentication (mostly implemented)
|f) MD5-HMAC signing SMB PDUs when SPNEGO style SessionSetup
|used (Kerberos or NTLMSSP). Signing alreadyimplemented for NTLM
|and raw NTLMSSP already. This is important when enabling
|extended security and mounting to Windows 2003 Servers
|f) Directory entry caching relies on a 1 second timer, rather than
|using FindNotify or equivalent. - (started)
|g) A few byte range testcases fail due to POSIX vs. Windows/CIFS
|style byte range lock differences. Save byte range locks so
|reconnect can replay them.
|h) Support unlock all (unlock 0,MAX_OFFSET)
|by unlocking all known byte range locks that we locked on the file.
|i) quota support (needs minor kernel change since quota calls
|to make it to network filesystems or deviceless filesystems)
|j) investigate sync behavior (including syncpage) and check
|for proper behavior of intr/nointr
|k) hook lower into the sockets api (as NFS/SunRPC does) to avoid the
|extra copy in/out of the socket buffers in some cases.
|l) finish support for IPv6. This is mostly complete but
|needs a simple conversion of ipv6 to sin6_addr from the
|address in string representation.
|m) Better optimize open (and pathbased setfilesize) to reduce the
|oplock breaks coming from windows srv. Piggyback identical file
|opens on top of each other by incrementing reference count rather
|than resending (helps reduce server resource utilization and avoid
|spurious oplock breaks).
|o) Improve performance of readpages by sending more than one read
|at a time when 8 pages or more are requested. In conjuntion
|add support for async_cifs_readpages.
|p) Add support for storing symlink info to Windows servers
|in the Extended Attribute format their SFU clients would recognize.
|q) Finish fcntl D_NOTIFY support so kde and gnome file list windows
|will autorefresh (partially complete by Asser). Needs minor kernel
|vfs change to support removing D_NOTIFY on a file.
|r) Add GUI tool to configure /proc/fs/cifs settings and for display of
|the CIFS statistics (started)
|s) implement support for security and trusted categories of xattrs
|(requires minor protocol extension) to enable better support for SELINUX
|t) Implement O_DIRECT flag on open (already supported on mount)
|u) Create UID mapping facility so server UIDs can be mapped on a per
|mount or a per server basis to client UIDs or nobody if no mapping
|exists. This is helpful when Unix extensions are negotiated to
|allow better permission checking when UIDs differ on the server
|and client. Add new protocol request to the CIFS protocol
|standard for asking the server for the corresponding name of a
|v) Add support for CIFS Unix and also the newer POSIX extensions to the
|server side for Samba 4.
|w) Finish up the dos time conversion routines needed to return old server
|time to the client (default time, of now or time 0 is used now for these
|very old servers)
|x) Add support for OS/2 (LANMAN 1.2 and LANMAN2.1 based SMB servers)
|y) Finish testing of Windows 9x/Windows ME server support (started).
|KNOWN BUGS (updated April 29, 2005)
|See http://bugzilla.samba.org - search on product "CifsVFS" for
|current bug list.
|1) existing symbolic links (Windows reparse points) are recognized but
|can not be created remotely. They are implemented for Samba and those that
|support the CIFS Unix extensions, although earlier versions of Samba
|overly restrict the pathnames.
|2) follow_link and readdir code does not follow dfs junctions
|but recognizes them
|3) create of new files to FAT partitions on Windows servers can
|succeed but still return access denied (appears to be Windows
|server not cifs client problem) and has not been reproduced recently.
|NTFS partitions do not have this problem.
|4) debug connectathon lock test case 10 which fails against
|Samba (may be unmappable due to POSIX to Windows lock model
|differences but worth investigating). Also debug Samba to
|see why lock test case 7 takes longer to complete to Samba
|than to Windows.
|Misc testing to do
|1) check out max path names and max path name components against various server
|types. Try nested symlinks (8 deep). Return max path name in stat -f information
|2) Modify file portion of ltp so it can run against a mounted network
|share and run it against cifs vfs.
|3) Additional performance testing and optimization using iozone and similar -
|there are some easy changes that can be done to parallelize sequential writes,
|and when signing is disabled to request larger read sizes (larger than
|negotiated size) and send larger write sizes to modern servers.
|4) More exhaustively test against less common servers. More testing
|against Windows 9x, Windows ME servers.