Commit Graph

24 Commits

Author SHA1 Message Date
Pavel Shilovsky
4326ed2f6a CIFS: Decrypt and process small encrypted packets
Allow to decrypt transformed packets, find a corresponding mid
and process as usual further.

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
2017-02-01 16:46:36 -06:00
Pavel Shilovsky
026e93dc0a CIFS: Encrypt SMB3 requests before sending
This change allows to encrypt packets if it is required by a server
for SMB sessions or tree connections.

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
2017-02-01 16:46:36 -06:00
Pavel Shilovsky
738f9de5cd CIFS: Send RFC1001 length in a separate iov
In order to simplify further encryption support we need to separate
RFC1001 length and SMB2 header when sending a request. Put the length
field in iov[0] and the rest of the packet into following iovs.

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
2017-02-01 16:46:35 -06:00
Pavel Shilovsky
31473fc4f9 CIFS: Separate SMB2 header structure
In order to support compounding and encryption we need to separate
RFC1001 length field and SMB2 header structure because the protocol
treats them differently. This change will allow to simplify parsing
of such complex SMB2 packets further.

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
2017-02-01 16:46:34 -06:00
Al Viro
16c568efff cifs: merge the hash calculation helpers
three practically identical copies...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-03-28 14:05:27 -04:00
Steve French
373512ec5c Prepare for encryption support (first part). Add decryption and encryption key generation. Thanks to Metze for helping with this.
Reviewed-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Steve French <steve.french@primarydata.com>
2016-01-14 14:29:42 -06:00
Sachin Prabhu
9235d09873 Convert MessageID in smb2_hdr to LE
We have encountered failures when When testing smb2 mounts on ppc64
machines when using both Samba as well as Windows 2012.

On poking around, the problem was determined to be caused by the
high endian MessageID passed in the header for smb2. On checking the
corresponding MID for smb1 is converted to LE before being sent on the
wire.

We have tested this patch successfully on a ppc64 machine.

Signed-off-by: Sachin Prabhu <sprabhu@redhat.com>
2014-12-14 14:55:45 -06:00
Pavel Shilovsky
cb7e9eabb2 CIFS: Use multicredits for SMB 2.1/3 writes
If we negotiate SMB 2.1 and higher version of the protocol and
a server supports large write buffer size, we need to consume 1
credit per 65536 bytes. So, we need to know how many credits
we have and obtain the required number of them before constructing
a writedata structure in writepages and iovec write.

Reviewed-by: Shirish Pargaonkar <spargaonkar@suse.com>
Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Steve French <smfrench@gmail.com>
2014-08-02 01:23:03 -05:00
Shirish Pargaonkar
7f48558e64 cifs: Send a logoff request before removing a smb session
Send a smb session logoff request before removing smb session off of the list.
On a signed smb session, remvoing a session off of the list before sending
a logoff request results in server returning an error for lack of
smb signature.

Never seen an error during smb logoff, so as per MS-SMB2 3.2.5.1,
not sure how an error during logoff should be retried. So for now,
if a server returns an error to a logoff request, log the error and
remove the session off of the list.

Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2013-11-02 12:52:35 -05:00
Tim Gardner
3d378d3fd8 cifs: Make big endian multiplex ID sequences monotonic on the wire
The multiplex identifier (MID) in the SMB header is only
ever used by the client, in conjunction with PID, to match responses
from the server. As such, the endianess of the MID is not important.
However, When tracing packet sequences on the wire, protocol analyzers
such as wireshark display MID as little endian. It is much more informative
for the on-the-wire MID sequences to match debug information emitted by the
CIFS driver.  Therefore, one should write and read MID in the SMB header
assuming it is always little endian.

Observed from wireshark during the protocol negotiation
and session setup:

        Multiplex ID: 256
        Multiplex ID: 256
        Multiplex ID: 512
        Multiplex ID: 512
        Multiplex ID: 768
        Multiplex ID: 768

After this patch on-the-wire MID values begin at 1 and increase monotonically.

Introduce get_next_mid64() for the internal consumers that use the full 64 bit
multiplex identifier.

Introduce the helpers get_mid() and compare_mid() to make the endian
translation clear.

Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Tim Gardner <timg@tpi.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2013-11-02 12:51:53 -05:00
Shirish Pargaonkar
32811d242f cifs: Start using per session key for smb2/3 for signature generation
Switch smb2 code to use per session session key and smb3 code to
    use per session signing key instead of per connection key to
    generate signatures.

    For that, we need to find a session to fetch the session key to
    generate signature to match for every request and response packet.

    We also forgo checking signature for a session setup response
    from the server.

Acked-by: Jeff Layton <jlayton@samba.org>
Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2013-09-08 14:47:50 -05:00
Jeff Layton
ba48202932 cifs: fix bad error handling in crypto code
Jarod reported an Oops like when testing with fips=1:

CIFS VFS: could not allocate crypto hmacmd5
CIFS VFS: could not crypto alloc hmacmd5 rc -2
CIFS VFS: Error -2 during NTLMSSP authentication
CIFS VFS: Send error in SessSetup = -2
BUG: unable to handle kernel NULL pointer dereference at 000000000000004e
IP: [<ffffffff812b5c7a>] crypto_destroy_tfm+0x1a/0x90
PGD 0
Oops: 0000 [#1] SMP
Modules linked in: md4 nls_utf8 cifs dns_resolver fscache kvm serio_raw virtio_balloon virtio_net mperf i2c_piix4 cirrus drm_kms_helper ttm drm i2c_core virtio_blk ata_generic pata_acpi
CPU: 1 PID: 639 Comm: mount.cifs Not tainted 3.11.0-0.rc3.git0.1.fc20.x86_64 #1
Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
task: ffff88007bf496e0 ti: ffff88007b080000 task.ti: ffff88007b080000
RIP: 0010:[<ffffffff812b5c7a>]  [<ffffffff812b5c7a>] crypto_destroy_tfm+0x1a/0x90
RSP: 0018:ffff88007b081d10  EFLAGS: 00010282
RAX: 0000000000001f1f RBX: ffff880037422000 RCX: ffff88007b081fd8
RDX: 000000000000001f RSI: 0000000000000006 RDI: fffffffffffffffe
RBP: ffff88007b081d30 R08: ffff880037422000 R09: ffff88007c090100
R10: 0000000000000000 R11: 00000000fffffffe R12: fffffffffffffffe
R13: ffff880037422000 R14: ffff880037422000 R15: 00000000fffffffe
FS:  00007fc322f4f780(0000) GS:ffff88007fc80000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 000000000000004e CR3: 000000007bdaa000 CR4: 00000000000006e0
Stack:
 ffffffff81085845 ffff880037422000 ffff8800375e7400 ffff880037422000
 ffff88007b081d48 ffffffffa0176022 ffff880037422000 ffff88007b081d60
 ffffffffa015c07b ffff880037600600 ffff88007b081dc8 ffffffffa01610e1
Call Trace:
 [<ffffffff81085845>] ? __cancel_work_timer+0x75/0xf0
 [<ffffffffa0176022>] cifs_crypto_shash_release+0x82/0xf0 [cifs]
 [<ffffffffa015c07b>] cifs_put_tcp_session+0x8b/0xe0 [cifs]
 [<ffffffffa01610e1>] cifs_mount+0x9d1/0xad0 [cifs]
 [<ffffffffa014ff50>] cifs_do_mount+0xa0/0x4d0 [cifs]
 [<ffffffff811ab6e9>] mount_fs+0x39/0x1b0
 [<ffffffff811c466f>] vfs_kern_mount+0x5f/0xf0
 [<ffffffff811c6a9e>] do_mount+0x23e/0xa20
 [<ffffffff811c66e6>] ? copy_mount_options+0x36/0x170
 [<ffffffff811c7303>] SyS_mount+0x83/0xc0
 [<ffffffff8165c8d9>] system_call_fastpath+0x16/0x1b
Code: eb 9e 66 66 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 66 66 66 66 90 55 48 89 e5 41 55 41 54 49 89 fc 53 48 83 ec 08 48 85 ff 74 46 <48> 83 7e 48 00 48 8b 5e 50 74 4b 48 89 f7 e8 83 fc ff ff 4c 8b
RIP  [<ffffffff812b5c7a>] crypto_destroy_tfm+0x1a/0x90
 RSP <ffff88007b081d10>
CR2: 000000000000004e

The cifs code allocates some crypto structures. If that fails, it
returns an error, but it leaves the pointers set to their PTR_ERR
values. Then later when it tries to clean up, it sees that those values
are non-NULL and then passes them to the routine that frees them.

Fix this by setting the pointers to NULL after collecting the error code
in this situation.

Cc: Sachin Prabhu <sprabhu@redhat.com>
Reported-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2013-07-31 13:44:59 -05:00
Steve French
95dc8dd14e Limit allocation of crypto mechanisms to dialect which requires
Updated patch to try to prevent allocation of cifs, smb2 or smb3 crypto
secmech structures unless needed.  Currently cifs allocates all crypto
mechanisms when the first session is established (4 functions and
4 contexts), rather than only allocating these when needed (smb3 needs
two, the rest of the dialects only need one).

Acked-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2013-07-04 14:38:08 -05:00
Steve French
e65a5cb417 [CIFS] Fix build warning
Fix build warning in Shirish's recent SMB3 signing patch
which occurs when SMB2 support is disabled in Kconfig.

fs/built-in.o: In function `cifs_setup_session':
>> (.text+0xa1767): undefined reference to `generate_smb3signingkey'

Pointed out by: automated 0-DAY kernel build testing backend
Intel Open Source Technology Center

CC: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2013-06-27 01:06:50 -05:00
Steve French
429b46f4fd [CIFS] SMB3 Signing enablement
SMB3 uses a much faster method of signing (which is also better in other ways),
AES-CMAC.  With the kernel now supporting AES-CMAC since last release, we
are overdue to allow SMB3 signing (today only CIFS and SMB2 and SMB2.1,
but not SMB3 and SMB3.1 can sign) - and we need this also for checking
secure negotation and also per-share encryption (two other new SMB3 features
which we need to implement).

This patch needs some work in a few areas - for example we need to
move signing for SMB2/SMB3 from per-socket to per-user (we may be able to
use the "nosharesock" mount option in the interim for the multiuser case),
and Shirish found a bug in the earlier authentication overhaul
(setting signing flags properly) - but those can be done in followon
patches.

Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2013-06-26 23:45:05 -05:00
Jeff Layton
38d77c50b4 cifs: track the enablement of signing in the TCP_Server_Info
Currently, we determine this according to flags in the sec_mode, flags
in the global_secflags and via other methods. That makes the semantics
very hard to follow and there are corner cases where we don't handle
this correctly.

Add a new bool to the TCP_Server_Info that acts as a simple flag to tell
us whether signing is enabled on this connection or not, and fix up the
places that need to determine this to use that flag.

This is a bit weird for the SMB2 case, where signing is per-session.
SMB2 needs work in this area already though. The existing SMB2 code has
similar logic to what we're using here, so there should be no real
change in behavior. These changes should make it easier to implement
per-session signing in the future though.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <smfrench@gmail.com>
2013-06-24 01:56:43 -05:00
Joe Perches
f96637be08 [CIFS] cifs: Rename cERROR and cFYI to cifs_dbg
It's not obvious from reading the macro names that these macros
are for debugging.  Convert the names to a single more typical
kernel style cifs_dbg macro.

	cERROR(1, ...)   -> cifs_dbg(VFS, ...)
	cFYI(1, ...)     -> cifs_dbg(FYI, ...)
	cFYI(DBG2, ...)  -> cifs_dbg(NOISY, ...)

Move the terminating format newline from the macro to the call site.

Add CONFIG_CIFS_DEBUG function cifs_vfs_err to emit the
"CIFS VFS: " prefix for VFS messages.

Size is reduced ~ 1% when CONFIG_CIFS_DEBUG is set (default y)

$ size fs/cifs/cifs.ko*
   text    data     bss     dec     hex filename
 265245	   2525	    132	 267902	  4167e	fs/cifs/cifs.ko.new
 268359    2525     132  271016   422a8 fs/cifs/cifs.ko.old

Other miscellaneous changes around these conversions:

o Miscellaneous typo fixes
o Add terminating \n's to almost all formats and remove them
  from the macros to be more kernel style like.  A few formats
  previously had defective \n's
o Remove unnecessary OOM messages as kmalloc() calls dump_stack
o Coalesce formats to make grep easier,
  added missing spaces when coalescing formats
o Use %s, __func__ instead of embedded function name
o Removed unnecessary "cifs: " prefixes
o Convert kzalloc with multiply to kcalloc
o Remove unused cifswarn macro

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2013-05-04 22:17:23 -05:00
Steve French
38107d45cf Do not send SMB2 signatures for SMB3 frames
Restructure code to make SMB2 vs. SMB3 signing a protocol
specific op.  SMB3 signing (AES_CMAC) is not enabled yet,
but this restructuring at least makes sure we don't send
an smb2 signature on an smb3 signed connection. A followon
patch will add AES_CMAC and enable smb3 signing.

Signed-off-by: Steve French <smfrench@gmail.com>
Acked-by: Jeff Layton <jlayton@samba.org>
2012-12-09 19:45:45 -06:00
Jeff Layton
fec344e3f3 cifs: change cifs_call_async to use smb_rqst structs
For now, none of the callers populate rq_pages. That will be done for
writes in a later patch. While we're at it, change the prototype of
setup_async_request not to need a return pointer argument. Just
return the pointer to the mid_q_entry or an ERR_PTR.

Reviewed-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2012-09-24 21:46:31 -05:00
Jeff Layton
fb308a6f22 cifs: teach signing routines how to deal with arrays of pages in a smb_rqst
Use the smb_send_rqst helper function to kmap each page in the array
and update the hash for that chunk.

Reviewed-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2012-09-24 21:46:31 -05:00
Jeff Layton
0b688cfc8b cifs: change smb2 signing routines to use smb_rqst structs
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2012-09-24 21:46:30 -05:00
Pavel Shilovsky
3c1bf7e48e CIFS: Enable signing in SMB2
Use hmac-sha256 and rather than hmac-md5 that is used for CIFS/SMB.

Signature field in SMB2 header is 16 bytes instead of 8 bytes.

Automatically enable signing by client when requested by the server
when signing ability is available to the client.

Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Sachin Prabhu <sprabhu@redhat.com>
Signed-off-by: Pavel Shilovsky <piastryyy@gmail.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2012-09-24 21:46:28 -05:00
Pavel Shilovsky
c95b8eeda3 CIFS: Add SMB2 support for async requests
Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Steve French <smfrench@gmail.com>
2012-07-24 21:55:14 +04:00
Pavel Shilovsky
2dc7e1c033 CIFS: Make transport routines work with SMB2
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <smfrench@gmail.com>
2012-07-24 10:25:20 -05:00