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Currently the way the tid (tree connection) status is tracked
is confusing. The same enum is used for structs cifs_tcon
and cifs_ses and TCP_Server_info, but each of these three has
different states that they transition among. The current
code also unnecessarily uses camelCase.
Convert from use of statusEnum to a new tid_status_enum for
tree connections. The valid states for a tid are:
TID_NEW = 0,
TID_GOOD,
TID_EXITING,
TID_NEED_RECON,
TID_NEED_TCON,
TID_IN_TCON,
TID_NEED_FILES_INVALIDATE, /* unused, considering removing in future */
TID_IN_FILES_INVALIDATE
It also removes CifsNeedTcon, CifsInTcon, CifsNeedFilesInvalidate and
CifsInFilesInvalidate from the statusEnum used for session and
TCP_Server_Info since they are not relevant for those.
A follow on patch will fix the places where we use the
tcon->need_reconnect flag to be more consistent with the tid->status.
Also fixes a bug that was:
Reported-by: kernel test robot <lkp@intel.com>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
The bug is here:
if (!tcon) {
resched = true;
list_del_init(&ses->rlist);
cifs_put_smb_ses(ses);
Because the list_for_each_entry() never exits early (without any
break/goto/return inside the loop), the iterator 'ses' after the
loop will always be an pointer to a invalid struct containing the
HEAD (&pserver->smb_ses_list). As a result, the uses of 'ses' above
will lead to a invalid memory access.
The original intention should have been to walk each entry 'ses' in
'&tmp_ses_list', delete '&ses->rlist' and put 'ses'. So fix it with
a list_for_each_entry_safe().
Cc: stable@vger.kernel.org # 5.17
Fixes: 3663c9045f ("cifs: check reconnects for channels of active tcons too")
Signed-off-by: Xiaomeng Tong <xiam0nd.tong@gmail.com>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
The client used to partially convert the fids to le64, while storing
or sending them by using host endianness. This broke the client on
big-endian machines. Instead of converting them to le64, store them
as opaque integers and then avoid byteswapping when sending them over
wire.
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Namjae Jeon <linkinjeon@kernel.org>
Reviewed-by: Tom Talpey <tom@talpey.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
For improved debugging it can be helpful to send version information
as other clients do during NTLMSSP negotiation. See protocol document
MS-NLMP section 2.2.1.1
Set the major and minor versions based on the kernel version, and the
BuildNumber based on the internal cifs.ko module version number,
and following the recommendation in the protocol documentation
(MS-NLMP section 2.2.10) we set the NTLMRevisionCurrent field to 15.
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
The status of tcp session, smb session and tcon have the
same flow, irrespective of the SMB version used. Hence
these status checks and updates should happen in the
version independent callers of these commands.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
ses_selected is being declared and set at several places. It is not
being used. Remove it.
Signed-off-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
A spin lock called chan_lock was introduced recently.
But not all accesses were protected. Doing that with
this change.
To make sure that a channel is not freed when in use,
we need to introduce a ref count. But today, we don't
ever free channels.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Recent changes to multichannel required some adjustments in
the way connection states transitioned during/after reconnect.
Also some minor fixes:
1. A pending switch of GlobalMid_Lock to cifs_tcp_ses_lock
2. Relocations of the code that logs reconnect
3. Changed some code in allocate_mid to suit the new scheme
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
With the new multichannel logic, when a channel needs reconnection,
the tree connect and other channels can still be active.
This fix will handle cases of checking for channel reconnect,
when the tcon does not need reconnect.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
alloc_path_with_tree_prefix() concatenates tree prefix and the path.
Windows CIFS client does not add separator after the tree prefix if the path
is empty. Let's do the same.
This fixes mounting DFS namespaces with names containing non-ASCII symbols.
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=215440
Signed-off-by: Eugene Korenevsky <ekorenevsky@astralinux.ru>
Signed-off-by: Steve French <stfrench@microsoft.com>
When a TCP connection gets reestablished by the sender in cifs_reconnect,
There is a chance for race condition with demultiplex thread waiting in
cifs_readv_from_socket on the old socket. It will now return -ECONNRESET.
This condition is handled by comparing socket pointer before and after
sock_recvmsg. If the socket pointer has changed, we should not call
cifs_reconnect again, but instead retry with new socket.
Also fixed another bug in my prev mchan commits.
We should always reestablish session (even if binding) on a channel
that needs reconnection.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
If functions like cifs_negotiate_protocol, cifs_setup_session,
cifs_tree_connect are called in parallel on different channels,
each of these will be execute the requests. This maybe unnecessary
in some cases, and only the first caller may need to do the work.
This is achieved by having more states for the tcp/smb/tcon session
status fields. And tracking the state of reconnection based on the
state machine.
For example:
for tcp connections:
CifsNew/CifsNeedReconnect ->
CifsNeedNegotiate ->
CifsInNegotiate ->
CifsNeedSessSetup ->
CifsInSessSetup ->
CifsGood
for smb sessions:
CifsNew/CifsNeedReconnect ->
CifsGood
for tcon:
CifsNew/CifsNeedReconnect ->
CifsInFilesInvalidate ->
CifsNeedTcon ->
CifsInTcon ->
CifsGood
If any channel reconnect sees that it's in the middle of
transition to CifsGood, then they can skip the function.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
While checking/updating status for tcp ses, smb ses or tcon,
we take GlobalMid_Lock. This doesn't make any sense.
Replaced it with cifs_tcp_ses_lock.
Ideally, we should take a spin lock per struct.
But since tcp ses, smb ses and tcon objects won't add up to a lot,
I think there should not be too much contention.
Also, in few other places, these are checked without locking.
Added locking for these.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
We use the concept of "binding" when one of the secondary channel
is in the process of connecting/reconnecting to the server. Till this
binding process completes, and the channel is bound to an existing session,
we redirect traffic from other established channels on the binding channel,
effectively blocking all traffic till individual channels get reconnected.
With my last set of commits, we can get rid of this binding serialization.
We now have a bitmap of connection states for each channel. We will use
this bitmap instead for tracking channel status.
Having a bitmap also now enables us to keep the session alive, as long
as even a single channel underneath is alive.
Unfortunately, this also meant that we need to supply the tcp connection
info for the channel during all negotiate and session setup functions.
These changes have resulted in a slightly bigger code churn.
However, I expect perf and robustness improvements in the mchan scenario
after this change.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
We needed a way to identify the channels under the smb session
which are in reconnect, so that the traffic to other channels
can continue. So I replaced the bool need_reconnect with
a bitmask identifying all the channels that need reconnection
(named chans_need_reconnect). When a channel needs reconnection,
the bit corresponding to the index of the server in ses->chans
is used to set this bitmask. Checking if no channels or all
the channels need reconnect then becomes very easy.
Also wrote some helper macros for checking and setting the bits.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
It is clearer to initialize rc at the beginning of the function.
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
Today, we don't have any way to get the smb session for any
of the secondary channels. Introducing a pointer to the primary
server from server struct of any secondary channel. The value will
be NULL for the server of the primary channel. This will enable us
to get the smb session for any channel.
This will be needed for some of the changes that I'm planning
to make soon.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Although unlikely for it to be possible for rsp to be null here,
the check is safer to add, and quiets a Coverity warning.
Addresses-Coverity: 1437501 ("Explicit Null dereference")
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
Although unlikely to be possible for rsp to be null here,
the check is safer to add, and quiets a Coverity warning.
Addresses-Coverity: 1420428 ("Explicit null dereferenced")
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
Although unlikely to be possible for rsp to be null here,
the check is safer to add, and quiets a Coverity warning.
Addresses-Coverity: 1418458 ("Explicit null dereferenced")
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
Although unlikely for it to be possible for rsp to be null here,
the check is safer to add, and quiets a Coverity warning.
Addresses-Coverity: 1443909 ("Explicit Null dereference")
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
Mounting a dfs link that has nested links was already supported at
mount(2), so make it work over reconnect as well.
Make the following case work:
* mount //root/dfs/link /mnt -o ...
- final share: /server/share
* in server settings
- change target folder of /root/dfs/link3 to /server/share2
- change target folder of /root/dfs/link2 to /root/dfs/link3
- change target folder of /root/dfs/link to /root/dfs/link2
* mount -o remount,... /mnt
- refresh all dfs referrals
- mark current connection for failover
- cifs_reconnect() reconnects to root server
- tree_connect()
* checks that /root/dfs/link2 is a link, then chase it
* checks that root/dfs/link3 is a link, then chase it
* finally tree connect to /server/share2
If the mounted share is no longer accessible and a reconnect had been
triggered, the client will retry it from both last referral
path (/root/dfs/link3) and original referral path (/root/dfs/link).
Any new referral paths found while chasing dfs links over reconnect,
it will be updated to TCP_Server_Info::leaf_fullpath, accordingly.
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
During the ntlmssp session setup (authenticate phases)
send the client workstation info. This can make debugging easier on
servers.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Enzo Matsumiya <ematsumiya@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
Move all SMB2_Create definitions (except contexts) into the shared area.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Move SMB2_SessionSetup, SMB2_Close, SMB2_Read, SMB2_Write and
SMB2_ChangeNotify commands into smbfs_common/smb2pdu.h
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
This file will contain all the definitions we need for SMB2 packets
and will follow the naming convention of MS-SMB2.PDF as closely
as possible to make it easier to cross-reference beween the definitions
and the standard.
The content of this file will mostly consist of migration of existing
definitions in the cifs/smb2.pdu.h and ksmbd/smb2pdu.h files
with some additional tweaks as the two files have diverged.
This patch introduces the new smbfs_common/smb2pdu.h file
and migrates the SMB2 header as well as TREE_CONNECT and TREE_DISCONNECT
to the shared file.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Address warning:
fs/smbfs_client/smb2pdu.c:2425 create_sd_buf()
warn: struct type mismatch 'smb3_acl vs cifs_acl'
Pointed out by Dan Carpenter via smatch code analysis tool
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
checkpatch complains about source files with filenames (e.g. in
these cases just below the SPDX header in comments at the top of
various files in fs/cifs). It also is helpful to change this now
so will be less confusing when the parent directory is renamed
e.g. from fs/cifs to fs/smb_client (or fs/smbfs)
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
We used to follow the rule earlier that the create SD context
always be a multiple of 8. However, with the change:
cifs: refactor create_sd_buf() and and avoid corrupting the buffer
...we recompute the length, and we failed that rule.
Fixing that with this change.
Cc: <stable@vger.kernel.org> # v5.10+
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Support for faster packet signing (using GMAC instead of CMAC) can
now be negotiated to some newer servers, including Windows.
See MS-SMB2 section 2.2.3.17.
This patch adds support for sending the new negotiate context
with the first of three supported signing algorithms (AES-CMAC)
and decoding the response. A followon patch will add support
for sending the other two (including AES-GMAC, which is fastest)
and changing the signing algorithm used based on what was
negotiated.
To allow the client to request GMAC signing set module parameter
"enable_negotiate_signing" to 1.
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
In preparation for FORTIFY_SOURCE performing compile-time and run-time
field bounds checking for memcpy(), memmove(), and memset(), avoid
intentionally reading across neighboring fields.
Instead of using memcpy to read across multiple struct members, just
perform per-member assignments as already done for other members.
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Although we may need this in some cases in the future, remove the
currently unused, non-compounded version of POSIX query info,
SMB11_posix_query_info (instead smb311_posix_query_path_info is now
called e.g. when revalidating dentries or retrieving info for getattr)
Addresses-Coverity: 1495708 ("Resource leaks")
Signed-off-by: Steve French <stfrench@microsoft.com>
tcon can not be null in SMB2_tcon function so the check
is not relevant and removing it makes Coverity happy.
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
Addresses-Coverity: 13250131 ("Dereference before null check")
Signed-off-by: Steve French <stfrench@microsoft.com>
Add SPDX license identifier and replace license boilerplate.
Corrects various checkpatch errors with the older format for
noting the LGPL license.
Signed-off-by: Steve French <stfrench@microsoft.com>
In posix_info_parse() we call posix_info_sid_size twice for each of the owner and the group
sid. The first time to check that it is valid, i.e. >= 0 and the second time
to just pass it in as a length to memcpy().
As this is a pure function we know that it can not be negative the second time and this
is technically a false warning in coverity.
However, as it is a pure function we are just wasting cycles by calling it a second time.
Record the length from the first time we call it and save some cycles as well as make
Coverity happy.
Addresses-Coverity-ID: 1491379 ("Argument can not be negative")
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
SMB3.0 doesn't have encryption negotiate context but simply uses
the SMB2_GLOBAL_CAP_ENCRYPTION flag.
When that flag is present in the neg response cifs.ko uses AES-128-CCM
which is the only cipher available in this context.
cipher_type was set to the server cipher only when parsing encryption
negotiate context (SMB3.1.1).
For SMB3.0 it was set to 0. This means cipher_type value can be 0 or 1
for AES-128-CCM.
Fix this by checking for SMB3.0 and encryption capability and setting
cipher_type appropriately.
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
See MS-SMB2 3.2.4.1.4, file ids in compounded requests should be set to
0xFFFFFFFFFFFFFFFF (we were treating it as u32 not u64 and setting
it incorrectly).
Signed-off-by: Steve French <stfrench@microsoft.com>
Reported-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
In the SMB3/SMB3.1.1 negotiate protocol request, we are supposed to
advertise CAP_MULTICHANNEL capability when establishing multiple
channels has been requested by the user doing the mount. See MS-SMB2
sections 2.2.3 and 3.2.5.2
Without setting it there is some risk that multichannel could fail
if the server interpreted the field strictly.
Reviewed-By: Tom Talpey <tom@talpey.com>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Cc: <stable@vger.kernel.org> # v5.8+
Signed-off-by: Steve French <stfrench@microsoft.com>
These functions will eventually be used to cache any directory, not just the root
so change the names.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
When doing a large read or write workload we only
very gradually increase the number of credits
which can cause problems with parallelizing large i/o
(I/O ramps up more slowly than it should for large
read/write workloads) especially with multichannel
when the number of credits on the secondary channels
starts out low (e.g. less than about 130) or when
recovering after server throttled back the number
of credit.
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
We used to share the CIFS_NEG_OP flag between negotiate and
session authentication. There was an assumption in the code that
CIFS_NEG_OP is used by negotiate only. So introcuded CIFS_SESS_OP
and used it for session setup optypes.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
SMB3.1.1 is the newest, and preferred dialect, and is included in
the requested dialect list by default (ie if no vers= is specified
on mount) but it should also be requested if SMB3 or later is requested
(vers=3 instead of a specific dialect: vers=2.1, vers=3.02 or vers=3.0).
Currently specifying "vers=3" only requests smb3.0 and smb3.02 but this
patch fixes it to also request smb3.1.1 dialect, as it is the newest
and most secure dialect and is a "version 3 or later" dialect (the intent
of "vers=3").
Signed-off-by: Steve French <stfrench@microsoft.com>
Suggested-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Retry close command if it gets interrupted to not leak open handles on
the server.
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reported-by: Duncan Findlay <duncf@duncf.ca>
Suggested-by: Pavel Shilovsky <pshilov@microsoft.com>
Fixes: 6988a619f5 ("cifs: allow syscalls to be restarted in __smb_send_rqst()")
Cc: stable@vger.kernel.org
Reviewd-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Fix passing of the additional security info via version
operations. Force new open when getting SACL and avoid
reuse of files that were previously open without
sufficient privileges to access SACLs.
Signed-off-by: Boris Protopopov <pboris@amazon.com>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Add SYSTEM_SECURITY access flag and use with smb2 when opening
files for getting/setting SACLs. Add "system.cifs_ntsd_full"
extended attribute to allow user-space access to the functionality.
Avoid multiple server calls when setting owner, DACL, and SACL.
Signed-off-by: Boris Protopopov <pboris@amazon.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
In the negotiate protocol preauth context, the server is not required
to populate the salt (although it is done by most servers) so do
not warn on mount.
We retain the checks (warn) that the preauth context is the minimum
size and that the salt does not exceed DataLength of the SMB response.
Although we use the defaults in the case that the preauth context
response is invalid, these checks may be useful in the future
as servers add support for additional mechanisms.
CC: Stable <stable@vger.kernel.org>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
When mounting with "idsfromsid" mount option, Azure
corrupted the owner SIDs due to excessive padding
caused by placing the owner fields at the end of the
security descriptor on create. Placing owners at the
front of the security descriptor (rather than the end)
is also safer, as the number of ACEs (that follow it)
are variable.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Suggested-by: Rohith Surabattula <rohiths@microsoft.com>
CC: Stable <stable@vger.kernel.org> # v5.8
Signed-off-by: Steve French <stfrench@microsoft.com>
Don't populate const array smb3_create_tag_posix on the stack but
instead make it static. Makes the object code smaller by 50 bytes.
Before:
text data bss dec hex filename
150184 47167 0 197351 302e7 fs/cifs/smb2pdu.o
After:
text data bss dec hex filename
150070 47231 0 197301 302b5 fs/cifs/smb2pdu.o
(gcc version 10.2.0)
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
There are cases where the server can return a cipher type of 0 and
it not be an error. For example server supported no encryption types
(e.g. server completely disabled encryption), or the server and
client didn't support any encryption types in common (e.g. if a
server only supported AES256_CCM). In those cases encryption would
not be supported, but that can be ok if the client did not require
encryption on mount and it should not return an error.
In the case in which mount requested encryption ("seal" on mount)
then checks later on during tree connection will return the proper
rc, but if seal was not requested by client, since server is allowed
to return 0 to indicate no supported cipher, we should not fail mount.
Reported-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>