Commit Graph

162 Commits

Author SHA1 Message Date
Jeff Layton ca83ce3d5b cifs: don't allow mmap'ed pages to be dirtied while under writeback (try #3)
This is more or less the same patch as before, but with some merge
conflicts fixed up.

If a process has a dirty page mapped into its page tables, then it has
the ability to change it while the client is trying to write the data
out to the server. If that happens after the signature has been
calculated then that signature will then be wrong, and the server will
likely reset the TCP connection.

This patch adds a page_mkwrite handler for CIFS that simply takes the
page lock. Because the page lock is held over the life of writepage and
writepages, this prevents the page from becoming writeable until
the write call has completed.

With this, we can also remove the "sign_zero_copy" module option and
always inline the pages when writing.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-04-12 14:19:55 +00:00
Steve French fd88ce9313 [CIFS] cifs: clarify the meaning of tcpStatus == CifsGood
When the TCP_Server_Info is first allocated and connected, tcpStatus ==
CifsGood means that the NEGOTIATE_PROTOCOL request has completed and the
socket is ready for other calls. cifs_reconnect however sets tcpStatus
to CifsGood as soon as the socket is reconnected and the optional
RFC1001 session setup is done. We have no clear way to tell the
difference between these two states, and we need to know this in order
to know whether we can send an echo or not.

Resolve this by adding a new statusEnum value -- CifsNeedNegotiate. When
the socket has been connected but has not yet had a NEGOTIATE_PROTOCOL
request done, set it to this value. Once the NEGOTIATE is done,
cifs_negotiate_protocol will set tcpStatus to CifsGood.

This also fixes and cleans the logic in cifs_reconnect and
cifs_reconnect_tcon. The old code checked for specific states when what
it really wants to know is whether the state has actually changed from
CifsNeedReconnect.

Reported-and-Tested-by: JG <jg@cms.ac>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-04-12 01:01:14 +00:00
Steve French 2e325d5973 Max share size is too small
Max share name was set to 64, and (at least for Windows)
can be 80.

Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-04-12 00:47:14 +00:00
Steve French 8727c8a85f Allow user names longer than 32 bytes
We artificially limited the user name to 32 bytes, but modern servers handle
larger.  Set the maximum length to a reasonable 256, and make the user name
string dynamically allocated rather than a fixed size in session structure.
Also clean up old checkpatch warning.

Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-04-12 00:42:06 +00:00
Jeff Layton bdf1b03e09 cifs: replace /proc/fs/cifs/Experimental with a module parm
This flag currently only affects whether we allow "zero-copy" writes
with signing enabled. Typically we map pages in the pagecache directly
into the write request. If signing is enabled however and the contents
of the page change after the signature is calculated but before the
write is sent then the signature will be wrong. Servers typically
respond to this by closing down the socket.

Still, this can provide a performance benefit so the "Experimental" flag
was overloaded to allow this. That's really not a good place for this
option however since it's not clear what that flag does.

Move that flag instead to a new module parameter that better describes
its purpose. That's also better since it can be set at module insertion
time by configuring modprobe.d.

Reviewed-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-04-12 00:40:43 +00:00
Jeff Layton 71823baff1 cifs: don't always drop malformed replies on the floor (try #3)
Slight revision to this patch...use min_t() instead of conditional
assignment. Also, remove the FIXME comment and replace it with the
explanation that Steve gave earlier.

After receiving a packet, we currently check the header. If it's no
good, then we toss it out and continue the loop, leaving the caller
waiting on that response.

In cases where the packet has length inconsistencies, but the MID is
valid, this leads to unneeded delays. That's especially problematic now
that the client waits indefinitely for responses.

Instead, don't immediately discard the packet if checkSMB fails. Try to
find a matching mid_q_entry, mark it as having a malformed response and
issue the callback.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-02-11 03:59:12 +00:00
Steve French 7e90d705fc [CIFS] Do not send SMBEcho requests on new sockets until SMBNegotiate
In order to determine whether an SMBEcho request can be sent
we need to know that the socket is established (server tcpStatus == CifsGood)
AND that an SMB NegotiateProtocol has been sent (server maxBuf != 0).
Without the second check we can send an Echo request during reconnection
before the server can accept it.

CC: JG <jg@cms.ac>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-02-08 23:52:32 +00:00
Rob Landley f1d0c99865 Make CIFS mount work in a container.
Teach cifs about network namespaces, so mounting uses adresses/routing
visible from the container rather than from init context.

A container is a chroot on steroids that changes more than just the root
filesystem the new processes see.  One thing containers can isolate is
"network namespaces", meaning each container can have its own set of
ethernet interfaces, each with its own own IP address and routing to the
outside world.  And if you open a socket in _userspace_ from processes
within such a container, this works fine.

But sockets opened from within the kernel still use a single global
networking context in a lot of places, meaning the new socket's address
and routing are correct for PID 1 on the host, but are _not_ what
userspace processes in the container get to use.

So when you mount a network filesystem from within in a container, the
mount code in the CIFS driver uses the host's networking context and not
the container's networking context, so it gets the wrong address, uses
the wrong routing, and may even try to go out an interface that the
container can't even access...  Bad stuff.

This patch copies the mount process's network context into the CIFS
structure that stores the rest of the server information for that mount
point, and changes the socket open code to use the saved network context
instead of the global network context.  I.E. "when you attempt to use
these addresses, do so relative to THIS set of network interfaces and
routing rules, not the old global context from back before we supported
containers".

The big long HOWTO sets up a test environment on the assumption you've
never used ocntainers before.  It basically says:

1) configure and build a new kernel that has container support
2) build a new root filesystem that includes the userspace container
control package (LXC)
3) package/run them under KVM (so you don't have to mess up your host
system in order to play with containers).
4) set up some containers under the KVM system
5) set up contradictory routing in the KVM system and the container so
that the host and the container see different things for the same address
6) try to mount a CIFS share from both contexts so you can both force it
to work and force it to fail.

For a long drawn out test reproduction sequence, see:

  http://landley.livejournal.com/47024.html
  http://landley.livejournal.com/47205.html
  http://landley.livejournal.com/47476.html

Signed-off-by: Rob Landley <rlandley@parallels.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-01-24 04:28:51 +00:00
Jeff Layton aae62fdb6b cifs: move time field in cifsInodeInfo
...and remove length qualifiers from bools.

Before:

	/* size: 1176, cachelines: 19, members: 13 */
	/* sum members: 1165, holes: 2, sum holes: 11 */
	/* bit holes: 1, sum bit holes: 4 bits */
	/* last cacheline: 24 bytes */

After:

	/* size: 1168, cachelines: 19, members: 13 */
	/* last cacheline: 16 bytes */

...savings of 8 bytes per inode.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Pavel Shilovsky <piastryyy@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-01-20 21:46:26 +00:00
Jeff Layton c3dccf4817 cifs: TCP_Server_Info diet
Remove fields that are completely unused, and rearrange struct
according to recommendations by "pahole".

Before:

	/* size: 1112, cachelines: 18, members: 49 */
	/* sum members: 1086, holes: 8, sum holes: 26 */
	/* bit holes: 1, sum bit holes: 7 bits */
	/* last cacheline: 24 bytes */

After:

	/* size: 1072, cachelines: 17, members: 42 */
	/* sum members: 1065, holes: 3, sum holes: 7 */
	/* last cacheline: 48 bytes */

...savings of 40 bytes per struct on x86_64. 21 bytes by field removal,
and 19 by reorganizing to eliminate holes.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-01-20 21:46:22 +00:00
Jeff Layton 7749981ec3 cifs: remove code for setting timeouts on requests
Since we don't time out individual requests anymore, remove the code
that we used to use for setting timeouts on different requests.

Reviewed-by: Pavel Shilovsky <piastryyy@gmail.com>
Reviewed-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-01-20 18:07:55 +00:00
Steve French fda3594362 [CIFS] cifs: reconnect unresponsive servers
If the server isn't responding to echoes, we don't want to leave tasks
hung waiting for it to reply. At that point, we'll want to reconnect
so that soft mounts can return an error to userspace quickly.

If the client hasn't received a reply after a specified number of echo
intervals, assume that the transport is down and attempt to reconnect
the socket.

The number of echo_intervals to wait before attempting to reconnect is
tunable via a module parameter. Setting it to 0, means that the client
will never attempt to reconnect. The default is 5.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
2011-01-20 18:06:34 +00:00
Jeff Layton c74093b694 cifs: set up recurring workqueue job to do SMB echo requests
Reviewed-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-01-20 17:48:10 +00:00
Jeff Layton 2b84a36c55 cifs: allow for different handling of received response
In order to incorporate async requests, we need to allow for a more
general way to do things on receive, rather than just waking up a
process.

Turn the task pointer in the mid_q_entry into a callback function and a
generic data pointer. When a response comes in, or the socket is
reconnected, cifsd can call the callback function in order to wake up
the process.

The default is to just wake up the current process which should mean no
change in behavior for existing code.

Also, clean up the locking in cifs_reconnect. There doesn't seem to be
any need to hold both the srv_mutex and GlobalMid_Lock when walking the
list of mids.

Reviewed-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-01-20 17:43:59 +00:00
Jeff Layton 20054bd657 cifs: use CreationTime like an i_generation field
Reduce false inode collisions by using the CreationTime like an
i_generation field. This way, even if the server ends up reusing
a uniqueid after a delete/create cycle, we can avoid matching
the inode incorrectly.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-01-09 23:43:00 +00:00
Jeff Layton a0f8b4fb4c cifs: remove unnecessary locking around sequence_number
The server->sequence_number is already protected by the srv_mutex. The
GlobalMid_lock is unneeded here.

Reviewed-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-01-09 23:38:20 +00:00
Pavel Shilovsky a9f1b85e5b CIFS: Simplify ipv*_connect functions into one (try #4)
Make connect logic more ip-protocol independent and move RFC1001 stuff into
a separate function. Also replace union addr in TCP_Server_Info structure
with sockaddr_storage.

Signed-off-by: Pavel Shilovsky <piastryyy@gmail.com>
Reviewed-and-Tested-by: Jeff Layton <jlayton@samba.org>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-01-06 19:07:53 +00:00
Jeff Layton 8846399968 cifs: remove Local_System_Name
...this string is zeroed out and nothing ever changes it.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-12-06 22:45:19 +00:00
Suresh Jayaraman 6d20e8406f cifs: add attribute cache timeout (actimeo) tunable
Currently, the attribute cache timeout for CIFS is hardcoded to 1 second. This
means that the client might have to issue a QPATHINFO/QFILEINFO call every 1
second to verify if something has changes, which seems too expensive. On the
other hand, if the timeout is hardcoded to a higher value, workloads that
expect strict cache coherency might see unexpected results.

Making attribute cache timeout as a tunable will allow us to make a tradeoff
between performance and cache metadata correctness depending on the
application/workload needs.

Add 'actimeo' tunable that can be used to tune the attribute cache timeout.
The default timeout is set to 1 second. Also, display actimeo option value in
/proc/mounts.

It appears to me that 'actimeo' and the proposed (but not yet merged)
'strictcache' option cannot coexist, so care must be taken that we reset the
other option if one of them is set.

Changes since last post:
   - fix option parsing and handle possible values correcly

Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-12-02 19:32:11 +00:00
Jeff Layton b647c35f77 cifs: convert tlink_tree to a rbtree
Radix trees are ideal when you want to track a bunch of pointers and
can't embed a tracking structure within the target of those pointers.
The tradeoff is an increase in memory, particularly if the tree is
sparse.

In CIFS, we use the tlink_tree to track tcon_link structs. A tcon_link
can never be in more than one tlink_tree, so there's no impediment to
using a rb_tree here instead of a radix tree.

Convert the new multiuser mount code to use a rb_tree instead. This
should reduce the memory required to manage the tlink_tree.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-11-02 19:20:23 +00:00
Shirish Pargaonkar d3686d54c7 cifs: Cleanup and thus reduce smb session structure and fields used during authentication
Removed following fields from smb session structure
 cryptkey, ntlmv2_hash, tilen, tiblob
and ntlmssp_auth structure is allocated dynamically only if the auth mech
in NTLMSSP.

response field within a session_key structure is used to initially store the
target info (either plucked from type 2 challenge packet in case of NTLMSSP
or fabricated in case of NTLMv2 without extended security) and then to store
Message Authentication Key (mak) (session key + client response).

Server challenge or cryptkey needed during a NTLMSSP authentication
is now part of ntlmssp_auth structure which gets allocated and freed
once authenticaiton process is done.

Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-10-29 01:47:33 +00:00
Shirish Pargaonkar d3ba50b17a NTLM auth and sign - Use appropriate server challenge
Need to have cryptkey or server challenge in smb connection
(struct TCP_Server_Info) for ntlm and ntlmv2 auth types for which
cryptkey (Encryption Key) is supplied just once in Negotiate Protocol
response during an smb connection setup for all the smb sessions over
that smb connection.

For ntlmssp, cryptkey or server challenge is provided for every
smb session in type 2 packet of ntlmssp negotiation, the cryptkey
provided during Negotiation Protocol response before smb connection
does not count.

Rename cryptKey to cryptkey and related changes.

Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-10-29 01:47:30 +00:00
Shirish Pargaonkar f7c5445a9d NTLM auth and sign - minor error corrections and cleanup
Minor cleanup - Fix spelling mistake, make meaningful (goto) label

In function setup_ntlmv2_rsp(), do not return 0 and leak memory,
let the tiblob get freed.

For function find_domain_name(), pass already available nls table pointer
instead of loading and unloading the table again in this function.

For ntlmv2, the case sensitive password length is the length of the
response, so subtract session key length (16 bytes) from the .len.

Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-10-27 02:04:30 +00:00
Shirish Pargaonkar d2b915210b NTLM auth and sign - Define crypto hash functions and create and send keys needed for key exchange
Mark dependency on crypto modules in Kconfig.

Defining per structures sdesc and cifs_secmech which are used to store
crypto hash functions and contexts.  They are stored per smb connection
and used for all auth mechs to genereate hash values and signatures.

Allocate crypto hashing functions, security descriptiors, and respective
contexts when a smb/tcp connection is established.
Release them when a tcp/smb connection is taken down.

md5 and hmac-md5 are two crypto hashing functions that are used
throught the life of an smb/tcp connection by various functions that
calcualte signagure and ntlmv2 hash, HMAC etc.

structure ntlmssp_auth is defined as per smb connection.

ntlmssp_auth holds ciphertext which is genereated by rc4/arc4 encryption of
secondary key, a nonce using ntlmv2 session key and sent in the session key
field of the type 3 message sent by the client during ntlmssp
negotiation/exchange

A key is exchanged with the server if client indicates so in flags in
type 1 messsage and server agrees in flag in type 2 message of ntlmssp
negotiation.  If both client and agree, a key sent by client in
type 3 message of ntlmssp negotiation in the session key field.
The key is a ciphertext generated off of secondary key, a nonce, using
ntlmv2 hash via rc4/arc4.

Signing works for ntlmssp in this patch. The sequence number within
the server structure needs to be zero until session is established
i.e. till type 3 packet of ntlmssp exchange of a to be very first
smb session on that smb connection is sent.

Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-10-26 18:35:31 +00:00
Shirish Pargaonkar 21e733930b NTLM auth and sign - Allocate session key/client response dynamically
Start calculating 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 copy/make its
session key, session key of smb connection.  This key stays with
the smb connection throughout its life.
sequence_number within server is set to 0x2.

The authentication Message Authentication Key (mak) which consists
of session key followed by client response within structure session_key
is now dynamic.  Every authentication type allocates the key + response
sized memory within its session structure and later either assigns or
frees it once the client response is sent and if session's session key
becomes connetion's session key.

ntlm/ntlmi authentication functions are rearranged.  A function
named setup_ntlm_resp(), similar to setup_ntlmv2_resp(), replaces
function cifs_calculate_session_key().

size of CIFS_SESS_KEY_SIZE is changed to 16, to reflect the byte size
of the key it holds.

Reviewed-by: Jeff Layton <jlayton@samba.org>
Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-10-26 18:20:10 +00:00
Suresh Jayaraman 6573e9b73e cifs: update comments - [s/GlobalSMBSesLock/cifs_file_list_lock/g]
GlobalSMBSesLock is now cifs_file_list_lock. Update comments to reflect this.

Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-10-25 00:19:01 +00:00
Jeff Layton eb4b756b1e cifs: eliminate cifsInodeInfo->write_behind_rc (try #6)
write_behind_rc is redundant and just adds complexity to the code. What
we really want to do instead is to use mapping_set_error to reset the
flags on the mapping when we find a writeback error and can't report it
to userspace yet.

For cifs_flush and cifs_fsync, we shouldn't reset the flags since errors
returned there do get reported to userspace.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Suresh Jayaraman <sjayaraman@suse.de>
Reviewed-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-10-25 00:19:00 +00:00
Steve French 6c0f6218ba [CIFS] Fix checkpatch warnings and bump cifs version number
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-10-25 00:19:00 +00:00
Jeff Layton 5f6dbc9e4a cifs: convert cifsFileInfo->count to non-atomic counter
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: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-10-25 00:18:59 +00:00
Steve French cdff08e766 [CIFS] move close processing from cifs_close to cifsFileInfo_put
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: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-10-21 22:46:14 +00:00
Suresh Jayaraman 3f9bcca782 cifs: convert cifs_tcp_ses_lock from a rwlock to a spinlock
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: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-10-21 13:14:27 +00:00
Jeff Layton b33879aa83 cifs: move cifsFileInfo_put to file.c
...and make it non-inlined in preparation for the move of most of
cifs_close to it.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-10-18 01:32:05 +00:00
Jeff Layton 4477288a10 cifs: convert GlobalSMBSeslock from a rwlock to regular spinlock
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: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-10-18 01:32:01 +00:00
Jeff Layton 2e396b83f6 cifs: eliminate pfile pointer from cifsFileInfo
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: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Suresh Jayaraman <sjayaraman@suse.de>
Acked-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-10-18 01:07:20 +00:00
Jeff Layton 15886177e4 cifs: clean up cifs_reopen_file
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: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Suresh Jayaraman <sjayaraman@suse.de>
Acked-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-10-18 01:04:19 +00:00
Shirish Pargaonkar 5d0d28824c NTLM authentication and signing - Calculate auth response per smb session
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: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-10-14 18:05:19 +00:00
Jeff Layton d7c86ff8cd cifs: don't use vfsmount to pin superblock for oplock breaks
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: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Suresh Jayaraman <sjayaraman@suse.de>
Acked-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-10-12 18:08:01 +00:00
Jeff Layton a5e18bc36e cifs: keep dentry reference in cifsFileInfo instead of inode reference
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: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Suresh Jayaraman <sjayaraman@suse.de>
Acked-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-10-12 18:06:42 +00:00
Steve French 13cd4b7f74 [CIFS] Various small checkpatch cleanups
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-10-07 18:46:32 +00:00
Jeff Layton 9d002df492 cifs: add routines to build sessions and tcons on the fly
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: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-10-07 18:18:00 +00:00
Jeff Layton 13cfb7334e cifs: have cifsFileInfo hold a reference to a tlink rather than tcon pointer
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: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-10-06 16:12:49 +00:00
Jeff Layton 7ffec37245 cifs: add refcounted and timestamped container for holding tcons
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: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-10-06 16:12:44 +00:00
Jeff Layton 0d424ad0a4 cifs: add cifs_sb_master_tcon and convert some callers to use it
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: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-09-29 19:04:33 +00:00
Jeff Layton f6acb9d059 cifs: temporarily rename cifs_sb->tcon to ptcon to catch stragglers
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-09-29 19:04:33 +00:00
Jeff Layton a6e8a8455c cifs: add function to get a tcon from cifs_sb
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: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-09-29 19:04:32 +00:00
Jeff Layton 5fe97cfddc cifs: add tcon field to cifsFileInfo struct
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: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-09-29 19:04:31 +00:00
Ben Greear 3eb9a8893a cifs: Allow binding to local IP address.
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:💯1,user=foo, ...

Acked-by: Jeff Layton <jlayton@redhat.com>
Acked-by: Dr. David Holder <david.holder@erion.co.uk>
Signed-off-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-09-29 19:04:29 +00:00
Shirish Pargaonkar 2b149f1197 cifs NTLMv2/NTLMSSP ntlmv2 within ntlmssp autentication code
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: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-09-29 19:04:29 +00:00
Shirish Pargaonkar 5f98ca9afb cifs NTLMv2/NTLMSSP Change variable name mac_key to session key to reflect the key it holds
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: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-09-29 19:04:29 +00:00
Steve French c8e56f1f4f Revert "[CIFS] Fix ntlmv2 auth with ntlmssp"
This reverts commit 9fbc590860.

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: Steve French <sfrench@us.ibm.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
CC: Shirish Pargaonkar <shirishp@us.ibm.com>
2010-09-08 21:10:58 +00:00