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: NSteve French <sfrench@us.ibm.com>

Fixes generated by 'codespell' and manually reviewed.
Signed-off-by: NLucas De Marchi <lucas.demarchi@profusion.mobi>

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

Follow-on patch to 7e90d705 which is already in Steve's tree...

The check for tcpStatus == CifsGood is not meaningful since it doesn't
indicate whether the NEGOTIATE request has been done. Also, clarify
why we're checking for maxBuf == 0.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

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

When the socket to the server is disconnected, the client more or less
immediately calls cifs_reconnect to reconnect the socket. The NegProt
and SessSetup however are not done until an actual call needs to be
made.

With the addition of the SMB echo code, it's possible that the server
will initiate a disconnect on an idle socket. The client will then
reconnect the socket but no NegotiateProtocol request is done. The
SMBEcho workqueue job will then eventually pop, and an SMBEcho will be
sent on the socket. The server will then reject it since no NegProt was
done.

The ideal fix would be to either have the socket not be reconnected
until we plan to use it, or to immediately do a NegProt when the
reconnect occurs. The code is not structured for this however. For now
we must just settle for not sending any echoes until the NegProt is
done.
Reported-by: NJG <jg@cms.ac>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Updating extended statistics here can cause slab memory corruption
if a callback function frees slab memory (mid_entry).
Signed-off-by: NShirish Pargaonkar <shirishpargaonkar@gmail.com>
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

length at this point is the length returned by the last kernel_recvmsg
call. total_read is the length of all of the data read so far. length
is more or less meaningless at this point, so use total_read for
everything.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NPavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Replaced md4 hashing function local to cifs module with kernel crypto APIs.
As a result, md4 hashing function and its supporting functions in
file md4.c are not needed anymore.

Cleaned up function declarations, removed forward function declarations,
and removed a header file that is being deleted from being included.

Verified that sec=ntlm/i, sec=ntlmv2/i, and sec=ntlmssp/i work correctly.
Signed-off-by: NShirish Pargaonkar <shirishpargaonkar@gmail.com>
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Use for switching on strict cache mode. In this mode the
client reads from the cache all the time it has Oplock Level II,
otherwise - read from the server. As for write - the client stores
a data in the cache in Exclusive Oplock case, otherwise - write
directly to the server.
Signed-off-by: NPavel Shilovsky <piastryyy@gmail.com>
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

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.htmlSigned-off-by: NRob Landley <rlandley@parallels.com>
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Signed-off-by: NJeff Layton <jlayton@redhat.com>
Acked-by: NPavel Shilovsky <piastryyy@gmail.com>
Reviewed-by: NShirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

It's possible that when we access the ByteCount that the alignment
will be off. Most CPUs deal with that transparently, but there's
usually some performance impact. Some CPUs raise an exception on
unaligned accesses.

Fix this by accessing the byte count using the get_unaligned and
put_unaligned inlined functions. While we're at it, fix the types
of some of the variables that end up getting returns from these
functions.
Acked-by: NPavel Shilovsky <piastryyy@gmail.com>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

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: NPavel Shilovsky <piastryyy@gmail.com>
Reviewed-by: NSuresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

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: NJeff Layton <jlayton@redhat.com>

Reviewed-by: NSuresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

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: NSuresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

NTLM response length was changed to 16 bytes instead of 24 bytes
that are sent in Tree Connection Request during share-level security
share mounts.  Revert it back to 24 bytes.
Reported-and-Tested-by: NGrzegorz Ozanski <grzegorz.ozanski@intel.com>
Acked-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NShirish Pargaonkar <shirishpargaonkar@gmail.com>
Acked-by: NSuresh Jayaraman <sjayaraman@suse.de>
Cc: stable@kernel.org
Signed-off-by: NSteve French <sfrench@us.ibm.com>

It's an atomic_t and the code accesses the "counter" field in it directly
instead of using atomic_read(). It also is sometimes accessed under a
spinlock and sometimes not. Move it out of the spinlock since we don't need
belt-and-suspenders for something that's just informational.
Reviewed-by: NSuresh Jayaraman <sjayaraman@suse.de>
Reviewed-by: NPavel Shilovsky <piastryyy@gmail.com>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

The TCP_Server_Info is refcounted and every SMB session holds a
reference to it. Thus, smb_ses_list is always going to be empty when
cifsd is coming down. This is dead code.
Reviewed-by: NSuresh Jayaraman <sjayaraman@suse.de>
Reviewed-by: NPavel Shilovsky <piastryyy@gmail.com>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

In commit 3e4b3e1f we separated the "uid" mount option such that it
no longer determined the owner of the credential cache by default. When
we did this, we added a new option to cifs.upcall (--legacy-uid) to
try to make it so that it would behave the same was as it did before.

This ignored a rather important point -- the kernel has no way to know
what options are being passed to cifs.upcall, so it doesn't know what
uid it should use to determine whether to match an existing krb5 session.

The simplest solution is to simply add a new "cruid=" mount option that
only governs the uid owner of the credential cache for the mount.

Unfortunately, this means that the --legacy-uid option in cifs.upcall was
ill-considered and is now useless, but I don't see a better way to deal
with this.

A patch for the mount.cifs manpage will follow once this patch has been
accepted.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

I see no real need to leave these sorts of options under an
EXPERIMENTAL ifdef. Since you need a mount option to turn this code
on, that only blows out the testing matrix.

local_leases has been under the EXPERIMENTAL tag for some time, but
it's only the mount option that's under this label. Move it out
from under this tag.

The NTLMSSP code is also under EXPERIMENTAL, but it needs a mount
option to turn it on, and in the future any distro will reasonably
want this enabled. Go ahead and move it out from under the
EXPERIMENTAL tag.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Acked-by: NSuresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

A number of places that deal with RFC1001/1002 negotiations have bare
"15" or "16" values. Replace them with RFC_1001_NAME_LEN and
RFC_1001_NAME_LEN_WITH_NULL.

The patch also cleans up some checkpatch warnings for code surrounding
the changes. This should apply cleanly on top of the patch to remove
Local_System_Name.
Reported-and-Reviwed-by: NShirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

If we have a share mounted by non-standard port and try to mount another share
on the same host with standard port, we connect to the first share again -
that's wrong. This patch fixes this bug.
Signed-off-by: NPavel Shilovsky <piastryyy@gmail.com>
Reviewed-by: NJeff Layton <jlayton@samba.org>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

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: NPavel Shilovsky <piastryyy@gmail.com>
Reviewed-and-Tested-by: NJeff Layton <jlayton@samba.org>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

It's possible that cifs_mount will call cifs_build_path_to_root on a
newly instantiated cifs_sb. In that case, it's likely that the
master_tlink pointer has not yet been instantiated.

Fix this by having cifs_build_path_to_root take a cifsTconInfo pointer
as well, and have the caller pass that in.
Reported-and-Tested-by: NRobbert Kouprie <robbert@exx.nl>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

This function will return 0 if everything went ok. Commit 9d002df4
however added a block of code after the following check for
rc == -EREMOTE. With that change and when rc == 0, doing the
"goto mount_fail_check" here skips that code, leaving the tlink_tree
and master_tlink pointer unpopulated. That causes an oops later
in cifs_root_iget.
Reported-and-Tested-by: NRobbert Kouprie <robbert@exx.nl>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

...this string is zeroed out and nothing ever changes it.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

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: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSuresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Currently, it is possible to specify 'fsc' mount option even if
CONFIG_CIFS_FSCACHE has not been set. The option is being ignored silently
while the user fscache functionality to work. Fix this by raising error when
the CONFIG option is not set.
Reported-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSuresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Noticed while reviewing (late) the rbtree conversion patchset (which has been merged
already).

Cc: Jeff Layton <jlayton@redhat.com>
Signed-off-by: NSuresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

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

This is the second version of this patch, the only difference between
it and the first one is that this explicitly makes cifs_sb_master_tlink
a static inline.

Instead of keeping a tag on the master tlink in the tree, just keep a
pointer to the master in the superblock. That eliminates the need for
using the radix tree to look up a tagged entry.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

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: NShirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

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: NShirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

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: NShirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

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

The cifs_convert_address() returns zero on error but this caller is
testing for negative returns.

Btw. "i" is unsigned here, so it's never negative.
Reviewed-by: NJeff Layton <jlayton@samba.org>
Signed-off-by: NDan Carpenter <error27@gmail.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

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: NJeff Layton <jlayton@samba.org>
Signed-off-by: NShirish Pargaonkar <shirishpargaonkar@gmail.com>
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>