Signed-off-by: NSteve French <sfrench@us.ibm.com>

The count for cifsFileInfo is currently an atomic, but that just adds
complexity for little value. We generally need to hold cifs_file_list_lock
to traverse the lists anyway so we might as well make this counter
non-atomic and simply use the cifs_file_list_lock to protect it.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NSuresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Now that it's feasible for a cifsFileInfo to outlive the filp under
which it was created, move the close processing into cifsFileInfo_put.

This means that the last user of the filehandle always does the actual
on the wire close call. This also allows us to get rid of the closePend
flag from cifsFileInfo. If we have an active reference to the file
then it's never going to have a close pending.

cifs_close is converted to simply put the filehandle.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NSuresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

cifs_tcp_ses_lock is a rwlock with protects the cifs_tcp_ses_list,
server->smb_ses_list and the ses->tcon_list. It also protects a few
ref counters in server, ses and tcon. In most cases the critical section
doesn't seem to be large, in a few cases where it is slightly large, there
seem to be really no benefit from concurrent access. I briefly considered RCU
mechanism but it appears to me that there is no real need.

Replace it with a spinlock and get rid of the last rwlock in the cifs code.
Signed-off-by: NSuresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

...and make it non-inlined in preparation for the move of most of
cifs_close to it.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NSuresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Convert this lock to a regular spinlock

A rwlock_t offers little value here. It's more expensive than a regular
spinlock unless you have a fairly large section of code that runs under
the read lock and can benefit from the concurrency.

Additionally, we need to ensure that the refcounting for files isn't
racy and to do that we need to lock areas that can increment it for
write. That means that the areas that can actually use a read_lock are
very few and relatively infrequently used.

While we're at it, change the name to something easier to type, and fix
a bug in find_writable_file. cifsFileInfo_put can sleep and shouldn't be
called while holding the lock.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NSuresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

All the remaining users of cifsFileInfo->pfile just use it to get
at the f_flags/f_mode. Now that we store that separately in the
cifsFileInfo, there's no need to consult the pfile at all from
a cifsFileInfo pointer.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NSuresh Jayaraman <sjayaraman@suse.de>
Acked-by: NDave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Add a f_flags field that holds the f_flags field from the filp. We'll
need this info in case the filp ever goes away before the cifsFileInfo
does. Have cifs_reopen_file use that value instead of filp->f_flags
too and have it take a cifsFileInfo arg instead of a filp.

While we're at it, get rid of some bogus cargo-cult NULL pointer
checks in that function and reduce the level of indentation.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NSuresh Jayaraman <sjayaraman@suse.de>
Acked-by: NDave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Start calculation auth response within a session.  Move/Add pertinet
data structures like session key, server challenge and ntlmv2_hash in
a session structure.  We should do the calculations within a session
before copying session key and response over to server data
structures because a session setup can fail.

Only after a very first smb session succeeds, it copies/makes its
session key, session key of smb connection.  This key stays with
the smb connection throughout its life.
Signed-off-by: NShirish Pargaonkar <shirishpargaonkar@gmail.com>
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Filesystems aren't really supposed to do anything with a vfsmount. It's
considered a layering violation since vfsmounts are entirely managed at
the VFS layer.

CIFS currently keeps an active reference to a vfsmount in order to
prevent the superblock vanishing before an oplock break has completed.
What we really want to do instead is to keep sb->s_active high until the
oplock break has completed. This patch borrows the scheme that NFS uses
for handling sillyrenames.

An atomic_t is added to the cifs_sb_info. When it transitions from 0 to
1, an extra reference to the superblock is taken (by bumping the
s_active value). When it transitions from 1 to 0, that reference is
dropped and a the superblock teardown may proceed if there are no more
references to it.

Also, the vfsmount pointer is removed from cifsFileInfo and from
cifs_new_fileinfo, and some bogus forward declarations are removed from
cifsfs.h.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NSuresh Jayaraman <sjayaraman@suse.de>
Acked-by: NDave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

cifsFileInfo is a bit problematic. It contains a reference back to the
struct file itself. This makes it difficult for a cifsFileInfo to exist
without a corresponding struct file.

It would be better instead of the cifsFileInfo just held info pertaining
to the open file on the server instead without any back refrences to the
struct file. This would allow it to exist after the filp to which it was
originally attached was closed.

Much of the use of the file pointer in this struct is to get at the
dentry.  Begin divorcing the cifsFileInfo from the struct file by
keeping a reference to the dentry. Since the dentry will have a
reference to the inode, we can eliminate the "pInode" field too and
convert the igrab/iput to dget/dput.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NSuresh Jayaraman <sjayaraman@suse.de>
Acked-by: NDave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Signed-off-by: NSteve French <sfrench@us.ibm.com>

This patch is rather large, but it's a bit difficult to do piecemeal...

For non-multiuser mounts, everything will basically work as it does
today. A call to cifs_sb_tlink will return the "master" tcon link.

Turn the tcon pointer in the cifs_sb into a radix tree that uses the
fsuid of the process as a key. The value is a new "tcon_link" struct
that contains info about a tcon that's under construction.

When a new process needs a tcon, it'll call cifs_sb_tcon. That will
then look up the tcon_link in the radix tree. If it exists and is
valid, it's returned.

If it doesn't exist, then we stuff a new tcon_link into the tree and
mark it as pending and then go and try to build the session/tcon.
If that works, the tcon pointer in the tcon_link is updated and the
pending flag is cleared.

If the construction fails, then we set the tcon pointer to an ERR_PTR
and clear the pending flag.

If the radix tree is searched and the tcon_link is marked pending
then we go to sleep and wait for the pending flag to be cleared.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

cifsFileInfo needs a pointer to a tcon, but it doesn't currently hold a
reference to it. Change it to keep a pointer to a tcon_link instead and
hold a reference to it.

That will keep the tcon from being freed until the file is closed.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Eventually, we'll need to track the use of tcons on a per-sb basis, so that
we know when it's ok to tear them down. Begin this conversion by adding a
new "tcon_link" struct and accessors that get it. For now, the core data
structures are untouched -- cifs_sb still just points to a single tcon and
the pointers are just cast to deal with the accessor functions. A later
patch will flesh this out.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

At mount time, we'll always need to create a tcon that will serve as a
template for others that are associated with the mount. This tcon is
known as the "master" tcon.

In some cases, we'll need to use that tcon regardless of who's accessing
the mount. Add an accessor function for the master tcon and go ahead and
switch the appropriate places to use it.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

When we convert cifs to do multiple sessions per mount, we'll need more
than one tcon per superblock. At that point "cifs_sb->tcon" will make
no sense. Add a new accessor function that gets a tcon given a cifs_sb.
For now, it just returns cifs_sb->tcon. Later it'll do more.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Eventually, we'll have more than one tcon per superblock. At that point,
we'll need to know which one is associated with a particular fid. For
now, this is just set from the cifs_sb->tcon pointer, but eventually
the caller of cifs_new_fileinfo will pass a tcon pointer in.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

When using multi-homed machines, it's nice to be able to specify
the local IP to use for outbound connections.  This patch gives
cifs the ability to bind to a particular IP address.

   Usage:  mount -t cifs -o srcaddr=192.168.1.50,user=foo, ...
   Usage:  mount -t cifs -o srcaddr=2002::100:1,user=foo, ...
Acked-by: NJeff Layton <jlayton@redhat.com>
Acked-by: NDr. David Holder <david.holder@erion.co.uk>
Signed-off-by: NBen Greear <greearb@candelatech.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Attribue Value (AV) pairs or Target Info (TI) pairs are part of
ntlmv2 authentication.
Structure ntlmv2_resp had only definition for two av pairs.
So removed it, and now allocation of av pairs is dynamic.
For servers like Windows 7/2008, av pairs sent by server in
challege packet (type 2 in the ntlmssp exchange/negotiation) can
vary.

Server sends them during ntlmssp negotiation. So when ntlmssp is used
as an authentication mechanism, type 2 challenge packet from server
has this information.  Pluck it and use the entire blob for
authenticaiton purpose.  If user has not specified, extract
(netbios) domain name from the av pairs which is used to calculate
ntlmv2 hash.  Servers like Windows 7 are particular about the AV pair
blob.

Servers like Windows 2003, are not very strict about the contents
of av pair blob used during ntlmv2 authentication.
So when security mechanism such as ntlmv2 is used (not ntlmv2 in ntlmssp),
there is no negotiation and so genereate a minimal blob that gets
used in ntlmv2 authentication as well as gets sent.

Fields tilen and tilbob are session specific.  AV pair values are defined.

To calculate ntlmv2 response we need ti/av pair blob.

For sec mech like ntlmssp, the blob is plucked from type 2 response from
the server.  From this blob, netbios name of the domain is retrieved,
if user has not already provided, to be included in the Target String
as part of ntlmv2 hash calculations.

For sec mech like ntlmv2, create a minimal, two av pair blob.

The allocated blob is freed in case of error.  In case there is no error,
this blob is used in calculating ntlmv2 response (in CalcNTLMv2_response)
and is also copied on the response to the server, and then freed.

The type 3 ntlmssp response is prepared on a buffer,
5 * sizeof of struct _AUTHENTICATE_MESSAGE, an empirical value large
enough to hold _AUTHENTICATE_MESSAGE plus a blob with max possible
10 values as part of ntlmv2 response and lmv2 keys and domain, user,
workstation  names etc.

Also, kerberos gets selected as a default mechanism if server supports it,
over the other security mechanisms.
Signed-off-by: NShirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Change name of variable mac_key to session key.
The reason mac_key was changed to session key is, this structure does not
hold message authentication code, it holds the session key (for ntlmv2,
ntlmv1 etc.).  mac is generated as a signature in cifs_calc* functions.
Signed-off-by: NShirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

This reverts commit 9fbc5908.

The change to kernel crypto and fixes to ntlvm2 and ntlmssp
series, introduced a regression.  Deferring this patch series
to 2.6.37 after Shirish fixes it.
Signed-off-by: NSteve French <sfrench@us.ibm.com>
Acked-by: NJeff Layton <jlayton@redhat.com>
CC: Shirish Pargaonkar <shirishp@us.ibm.com>

This reverts commit 2d20ca83.

    The change to kernel crypto and fixes to ntlvm2 and ntlmssp
    series, introduced a regression.  Deferring this patch series
    to 2.6.37 after Shirish fixes it.
Signed-off-by: NSteve French <sfrench@us.ibm.com>
Acked-by: NJeff Layton <jlayton@redhat.com>
CC: Shirish Pargaonkar <shirishp@us.ibm.com>

Eliminiate sparse warning during usage of crypto_shash_* APIs
       error: bad constant expression

Allocate memory for shash descriptors once, so that we do not kmalloc/kfree it
for every signature generation (shash descriptor for md5 hash).

From ed7538619817777decc44b5660b52268077b74f3 Mon Sep 17 00:00:00 2001
From: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Date: Tue, 24 Aug 2010 11:47:43 -0500
Subject: [PATCH] eliminate sparse warnings during crypto_shash_* APis usage
Signed-off-by: NShirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Make ntlmv2 as an authentication mechanism within ntlmssp
instead of ntlmv1.
Parse type 2 response in ntlmssp negotiation to pluck
AV pairs and use them to calculate ntlmv2 response token.
Also, assign domain name from the sever response in type 2
packet of ntlmssp and use that (netbios) domain name in
calculation of response.

Enable cifs/smb signing using rc4 and md5.

Changed name of the structure mac_key to session_key to reflect
the type of key it holds.

Use kernel crypto_shash_* APIs instead of the equivalent cifs functions.
Signed-off-by: NShirish Pargaonkar <shirishpargaonkar@gmail.com>
Acked-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Right now, there's no clear separation between the uid that owns the
credentials used to do the mount and the overriding owner of the files
on that mount.

Add a separate cred_uid field that is set to the real uid
of the mount user. Unlike the linux_uid, the uid= option does not
override this parameter. The parm is sent to cifs.upcall, which can then
preferentially use the creduid= parm instead of the uid= parm for
finding credentials.

This is not the only way to solve this. We could try to do all of this
in kernel instead by having a module parameter that affects what gets
passed in the uid= field of the upcall. That said, we have a lot more
flexibility to change things in userspace so I think it probably makes
sense to do it this way.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Define inode-level data storage objects (managed by cifsInodeInfo structs).
Each inode-level object is created in a super-block level object and is itself
a data storage object in to which pages from the inode are stored.

The inode object is keyed by UniqueId. The coherency data being used is
LastWriteTime, LastChangeTime and end of file reported by the server.
Signed-off-by: NSuresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Define superblock-level cache index objects (managed by cifsTconInfo structs).
Each superblock object is created in a server-level index object and in itself
an index into which inode-level objects are inserted.

The superblock object is keyed by sharename. The UniqueId/IndexNumber is used to
validate that the exported share is the same since we accessed it last time.
Signed-off-by: NSuresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

This patch replaces the earlier patch by the same name. The only
difference is that MAX_PASSWORD_SIZE has been increased to attempt to
match the limits that windows enforces.

Do a better job of matching sessions by authtype. Matching by username
for a Kerberos session is incorrect, and anonymous sessions need special
handling.

Also, in the case where we do match by username, we also need to match
by password. That ensures that someone else doesn't "borrow" an existing
session without needing to know the password.

Finally, passwords can be longer than 16 bytes. Bump MAX_PASSWORD_SIZE
to 512 to match the size that the userspace mount helper allows.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

The secType is a per-tcp session entity, but the current routine doesn't
verify that it is acceptible when attempting to match an existing TCP
session.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Define server-level cache index objects (as managed by TCP_ServerInfo structs)
and register then with FS-Cache. Each server object is created in the CIFS
top-level index object and is itself an index into which superblock-level
objects are inserted.

The server objects are now keyed by {IPaddress,family,port} tuple.
Signed-off-by: NSuresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

The ip_address field is not used and seems redundant as there is union addr
already and I don't see any future use as well.
Signed-off-by: NSuresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Add conditional compile macros to guard the header file against multiple
inclusion.
Signed-off-by: NSuresh Jayaraman <sjayaraman@suse.de>
Acked-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Workqueue can now handle high concurrency.  Use system_nrt_wq
instead of slow-work.

* Updated is_valid_oplock_break() to not call cifs_oplock_break_put()
  as advised by Steve French.  It might cause deadlock.  Instead,
  reference is increased after queueing succeeded and
  cifs_oplock_break() briefly grabs GlobalSMBSeslock before putting
  the cfile to make sure it doesn't put before the matching get is
  finished.

* Anton Blanchard reported that cifs conversion was using now gone
  system_single_wq.  Use system_nrt_wq which provides non-reentrance
  guarantee which is enough and much better.
Signed-off-by: NTejun Heo <tj@kernel.org>
Acked-by: NSteve French <sfrench@samba.org>
Cc: Anton Blanchard <anton@samba.org>

When we made serverino the default, we trusted that the field sent by the
server in the "uniqueid" field was actually unique. It turns out that it
isn't reliably so.

Samba, in particular, will just put the st_ino in the uniqueid field when
unix extensions are enabled. When a share spans multiple filesystems, it's
quite possible that there will be collisions. This is a server bug, but
when the inodes in question are a directory (as is often the case) and
there is a collision with the root inode of the mount, the result is a
kernel panic on umount.

Fix this by checking explicitly for directory inodes with the same
uniqueid. If that is the case, then we can assume that using server inode
numbers will be a problem and that they should be disabled.

Fixes Samba bugzilla 7407
Signed-off-by: NJeff Layton <jlayton@redhat.com>
CC: Stable <stable@kernel.org>
Reviewed-and-Tested-by: NSuresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

...rather than the secType. This allows us to get rid of the MSKerberos
securityEnum. The client just makes a decision at upcall time.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

...since that more accurately describes what that variable holds.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>