scsi: target: iscsi: Do not require target authentication

RFC7143 states that Initiator decides what type of authentication to
use:

The initiator MUST continue with:
CHAP_N=<N> CHAP_R=<R>
or, if it requires target authentication, with:
CHAP_N=<N> CHAP_R=<R> CHAP_I=<I> CHAP_C=<C>

Allow one way authentication if mutual authentication is configured. That
passes some tests from Windows HLK for Mutual CHAP with iSNS.

Link: https://lore.kernel.org/r/20220718152555.17084-5-d.bogdanov@yadro.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Dmitry Bogdanov <d.bogdanov@yadro.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: target: iscsi: Support base64 in CHAP

RFC7143 allows both Base64 and Hex encoding for CHAP binary entities like
Challenge and Response. Currently the Linux iSCSI target supports only Hex
encoding.

Add support for Base64 encoded CHAP Challenge and CHAP Response required
for CHAP tests in Windows HLK.

Link: https://lore.kernel.org/r/20220718152555.17084-3-d.bogdanov@yadro.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Dmitry Bogdanov <d.bogdanov@yadro.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: target: iscsi: Rename iscsi_conn to iscsit_conn

The structure iscsi_conn naming is used by the iSCSI initiator
driver. Rename the target conn to iscsit_conn to have more readable code.

Link: https://lore.kernel.org/r/20220428092939.36768-2-mgurtovoy@nvidia.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

mm, treewide: rename kzfree() to kfree_sensitive()

As said by Linus:

A symmetric naming is only helpful if it implies symmetries in use.
Otherwise it's actively misleading.

In "kzalloc()", the z is meaningful and an important part of what the
caller wants.

In "kzfree()", the z is actively detrimental, because maybe in the
future we really _might_ want to use that "memfill(0xdeadbeef)" or
something. The "zero" part of the interface isn't even _relevant_.

The main reason that kzfree() exists is to clear sensitive information
that should not be leaked to other future users of the same memory
objects.

Rename kzfree() to kfree_sensitive() to follow the example of the recently
added kvfree_sensitive() and make the intention of the API more explicit.
In addition, memzero_explicit() is used to clear the memory to make sure
that it won't get optimized away by the compiler.

The renaming is done by using the command sequence:

git grep -w --name-only kzfree |\
xargs sed -i 's/kzfree/kfree_sensitive/'

followed by some editing of the kfree_sensitive() kerneldoc and adding
a kzfree backward compatibility macro in slab.h.

[akpm@linux-foundation.org: fs/crypto/inline_crypt.c needs linux/slab.h]
[akpm@linux-foundation.org: fix fs/crypto/inline_crypt.c some more]

Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: David Howells <dhowells@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Cc: James Morris <jmorris@namei.org>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: Joe Perches <joe@perches.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: "Jason A . Donenfeld" <Jason@zx2c4.com>
Link: http://lkml.kernel.org/r/20200616154311.12314-3-longman@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

scsi: target: iscsi: rename some variables to avoid confusion.

This patch renames some variables in chap_server_compute_hash() to make it
harder to confuse the initiator's challenge with the target's challenge
when the mutual chap authentication is used.

Link: https://lore.kernel.org/r/20191017131037.9903-4-mlombard@redhat.com
Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: target: iscsi: tie the challenge length to the hash digest size

Link: https://lore.kernel.org/r/20191017131037.9903-3-mlombard@redhat.com
Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Tested-by: Chris Leech <cleech@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: target: iscsi: CHAP: add support for SHA1, SHA256 and SHA3-256

This patch modifies the chap_server_compute_hash() function to make it
agnostic to the choice of hash algorithm that is used. It also adds
support to three new hash algorithms: SHA1, SHA256 and SHA3-256.

The chap_got_response() function has been removed because the digest type
validity is already checked by chap_server_open()

Link: https://lore.kernel.org/r/20191028123822.5864-2-mlombard@redhat.com
Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Tested-by: Chris Leech <cleech@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: target: compare full CHAP_A Algorithm strings

RFC 2307 states:

For CHAP [RFC1994], in the first step, the initiator MUST send:

CHAP_A=<A1,A2...>

Where A1,A2... are proposed algorithms, in order of preference.
...
For the Algorithm, as stated in [RFC1994], one value is required to
be implemented:

5 (CHAP with MD5)

LIO currently checks for this value by only comparing a single byte in
the tokenized Algorithm string, which means that any value starting with
a '5' (e.g. "55") is interpreted as "CHAP with MD5". Fix this by
comparing the entire tokenized string.

Reviewed-by: Lee Duncan <lduncan@suse.com>
Reviewed-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: David Disseldorp <ddiss@suse.de>
Link: https://lore.kernel.org/r/20190912095547.22427-2-ddiss@suse.de
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: iscsi: set auth_protocol back to NULL if CHAP_A value is not supported

If the CHAP_A value is not supported, the chap_server_open() function
should free the auth_protocol pointer and set it to NULL, or we will leave
a dangling pointer around.

[ 66.010905] Unsupported CHAP_A value
[ 66.011660] Security negotiation failed.
[ 66.012443] iSCSI Login negotiation failed.
[ 68.413924] general protection fault: 0000 [#1] SMP PTI
[ 68.414962] CPU: 0 PID: 1562 Comm: targetcli Kdump: loaded Not tainted 4.18.0-80.el8.x86_64 #1
[ 68.416589] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011
[ 68.417677] RIP: 0010:__kmalloc_track_caller+0xc2/0x210

Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Reviewed-by: Chris Leech <cleech@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157

Based on 3 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version this program is distributed in the
hope that it will be useful but without any warranty without even
the implied warranty of merchantability or fitness for a particular
purpose see the gnu general public license for more details

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version [author] [kishon] [vijay] [abraham]
[i] [kishon]@[ti] [com] this program is distributed in the hope that
it will be useful but without any warranty without even the implied
warranty of merchantability or fitness for a particular purpose see
the gnu general public license for more details

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version [author] [graeme] [gregory]
[gg]@[slimlogic] [co] [uk] [author] [kishon] [vijay] [abraham] [i]
[kishon]@[ti] [com] [based] [on] [twl6030]_[usb] [c] [author] [hema]
[hk] [hemahk]@[ti] [com] this program is distributed in the hope
that it will be useful but without any warranty without even the
implied warranty of merchantability or fitness for a particular
purpose see the gnu general public license for more details

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1105 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.202006027@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

crypto: shash - remove shash_desc::flags

The flags field in 'struct shash_desc' never actually does anything.
The only ostensibly supported flag is CRYPTO_TFM_REQ_MAY_SLEEP.
However, no shash algorithm ever sleeps, making this flag a no-op.

With this being the case, inevitably some users who can't sleep wrongly
pass MAY_SLEEP. These would all need to be fixed if any shash algorithm
actually started sleeping. For example, the shash_ahash_*() functions,
which wrap a shash algorithm with the ahash API, pass through MAY_SLEEP
from the ahash API to the shash API. However, the shash functions are
called under kmap_atomic(), so actually they're assumed to never sleep.

Even if it turns out that some users do need preemption points while
hashing large buffers, we could easily provide a helper function
crypto_shash_update_large() which divides the data into smaller chunks
and calls crypto_shash_update() and cond_resched() for each chunk. It's
not necessary to have a flag in 'struct shash_desc', nor is it necessary
to make individual shash algorithms aware of this at all.

Therefore, remove shash_desc::flags, and document that the
crypto_shash_*() functions can be called from any context.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

scsi: target: iscsi: Use bin2hex instead of a re-implementation

Signed-off-by: Vincent Pelletier <plr.vincent@gmail.com>
Reviewed-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: target: iscsi: Use hex2bin instead of a re-implementation

This change has the following effects, in order of descreasing importance:

1) Prevent a stack buffer overflow

2) Do not append an unnecessary NULL to an anyway binary buffer, which
is writing one byte past client_digest when caller is:
chap_string_to_hex(client_digest, chap_r, strlen(chap_r));

The latter was found by KASAN (see below) when input value hes expected size
(32 hex chars), and further analysis revealed a stack buffer overflow can
happen when network-received value is longer, allowing an unauthenticated
remote attacker to smash up to 17 bytes after destination buffer (16 bytes
attacker-controlled and one null). As switching to hex2bin requires
specifying destination buffer length, and does not internally append any null,
it solves both issues.

This addresses CVE-2018-14633.

Beyond this:

- Validate received value length and check hex2bin accepted the input, to log
this rejection reason instead of just failing authentication.

- Only log received CHAP_R and CHAP_C values once they passed sanity checks.

==================================================================
BUG: KASAN: stack-out-of-bounds in chap_string_to_hex+0x32/0x60 [iscsi_target_mod]
Write of size 1 at addr ffff8801090ef7c8 by task kworker/0:0/1021

CPU: 0 PID: 1021 Comm: kworker/0:0 Tainted: G O 4.17.8kasan.sess.connops+ #2
Hardware name: To be filled by O.E.M. To be filled by O.E.M./Aptio CRB, BIOS 5.6.5 05/19/2014
Workqueue: events iscsi_target_do_login_rx [iscsi_target_mod]
Call Trace:
dump_stack+0x71/0xac
print_address_description+0x65/0x22e
? chap_string_to_hex+0x32/0x60 [iscsi_target_mod]
kasan_report.cold.6+0x241/0x2fd
chap_string_to_hex+0x32/0x60 [iscsi_target_mod]
chap_server_compute_md5.isra.2+0x2cb/0x860 [iscsi_target_mod]
? chap_binaryhex_to_asciihex.constprop.5+0x50/0x50 [iscsi_target_mod]
? ftrace_caller_op_ptr+0xe/0xe
? __orc_find+0x6f/0xc0
? unwind_next_frame+0x231/0x850
? kthread+0x1a0/0x1c0
? ret_from_fork+0x35/0x40
? ret_from_fork+0x35/0x40
? iscsi_target_do_login_rx+0x3bc/0x4c0 [iscsi_target_mod]
? deref_stack_reg+0xd0/0xd0
? iscsi_target_do_login_rx+0x3bc/0x4c0 [iscsi_target_mod]
? is_module_text_address+0xa/0x11
? kernel_text_address+0x4c/0x110
? __save_stack_trace+0x82/0x100
? ret_from_fork+0x35/0x40
? save_stack+0x8c/0xb0
? 0xffffffffc1660000
? iscsi_target_do_login+0x155/0x8d0 [iscsi_target_mod]
? iscsi_target_do_login_rx+0x3bc/0x4c0 [iscsi_target_mod]
? process_one_work+0x35c/0x640
? worker_thread+0x66/0x5d0
? kthread+0x1a0/0x1c0
? ret_from_fork+0x35/0x40
? iscsi_update_param_value+0x80/0x80 [iscsi_target_mod]
? iscsit_release_cmd+0x170/0x170 [iscsi_target_mod]
chap_main_loop+0x172/0x570 [iscsi_target_mod]
? chap_server_compute_md5.isra.2+0x860/0x860 [iscsi_target_mod]
? rx_data+0xd6/0x120 [iscsi_target_mod]
? iscsit_print_session_params+0xd0/0xd0 [iscsi_target_mod]
? cyc2ns_read_begin.part.2+0x90/0x90
? _raw_spin_lock_irqsave+0x25/0x50
? memcmp+0x45/0x70
iscsi_target_do_login+0x875/0x8d0 [iscsi_target_mod]
? iscsi_target_check_first_request.isra.5+0x1a0/0x1a0 [iscsi_target_mod]
? del_timer+0xe0/0xe0
? memset+0x1f/0x40
? flush_sigqueue+0x29/0xd0
iscsi_target_do_login_rx+0x3bc/0x4c0 [iscsi_target_mod]
? iscsi_target_nego_release+0x80/0x80 [iscsi_target_mod]
? iscsi_target_restore_sock_callbacks+0x130/0x130 [iscsi_target_mod]
process_one_work+0x35c/0x640
worker_thread+0x66/0x5d0
? flush_rcu_work+0x40/0x40
kthread+0x1a0/0x1c0
? kthread_bind+0x30/0x30
ret_from_fork+0x35/0x40

The buggy address belongs to the page:
page:ffffea0004243bc0 count:0 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0x17fffc000000000()
raw: 017fffc000000000 0000000000000000 0000000000000000 00000000ffffffff
raw: ffffea0004243c20 ffffea0004243ba0 0000000000000000 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
ffff8801090ef680: f2 f2 f2 f2 f2 f2 f2 01 f2 f2 f2 f2 f2 f2 f2 00
ffff8801090ef700: f2 f2 f2 f2 f2 f2 f2 00 02 f2 f2 f2 f2 f2 f2 00
>ffff8801090ef780: 00 f2 f2 f2 f2 f2 f2 00 00 f2 f2 f2 f2 f2 f2 00
^
ffff8801090ef800: 00 f2 f2 f2 f2 f2 f2 00 00 00 00 02 f2 f2 f2 f2
ffff8801090ef880: f2 f2 f2 00 00 00 00 00 00 00 00 f2 f2 f2 f2 00
==================================================================

Signed-off-by: Vincent Pelletier <plr.vincent@gmail.com>
Reviewed-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

target/iscsi: avoid NULL dereference in CHAP auth error path

If chap_server_compute_md5() fails early, e.g. via CHAP_N mismatch, then
crypto_free_shash() is called with a NULL pointer which gets
dereferenced in crypto_shash_tfm().

Fixes: 69110e3cedbb ("iscsi-target: Use shash and ahash")
Suggested-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: David Disseldorp <ddiss@suse.de>
Cc: stable@vger.kernel.org # 4.6+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

iscsi: ensure RNG is seeded before use

It's not safe to use weak random data here, especially for the challenge
response randomness. Since we're always in process context, it's safe to
simply wait until we have enough randomness to carry out the
authentication correctly.

While we're at it, we clean up a small memleak during an error
condition.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Cc: "Nicholas A. Bellinger" <nab@linux-iscsi.org>
Cc: Lee Duncan <lduncan@suse.com>
Cc: Chris Leech <cleech@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

target: Minimize #include directives

Remove superfluous #include directives from the include/target/*.h
files. Add missing #include directives to other *.h and *.c files.
Use forward declarations for structures where possible. This
change reduces the build time for make M=drivers/target on my
laptop from 27.1s to 18.7s or by about 30%.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Bryant G. Ly <bryantly@linux.vnet.ibm.com>

treewide: Fix typos in printk

This patch fix spelling typos in printk from various part
of the codes.

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

iscsi-target: Use shash and ahash

This patch replaces uses of the long obsolete hash interface with
either shash (for non-SG users) or ahash.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

iscsi-target: Move iscsi_target_[core,stat].h under linux include

Seems strange to see in include/target/iscsi/iscsi_transport.h:
include "../../../drivers/target/iscsi/iscsi_target_core.h"

Move it to it's natural location.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

iscsi-target; Enforce 1024 byte maximum for CHAP_C key value

This patch adds a check in chap_server_compute_md5() to enforce a
1024 byte maximum for the CHAP_C key value following the requirement
in RFC-3720 Section 11.1.4:

"..., C and R are large-binary-values and their binary length (not
the length of the character string that represents them in encoded
form) MUST not exceed 1024 bytes."

Reported-by: rahul.rane <rahul.rane@calsoftinc.com>
Tested-by: rahul.rane <rahul.rane@calsoftinc.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

iscsi-target: Convert chap_server_compute_md5 to use kstrtoul

This patch converts chap_server_compute_md5() from simple_strtoul() to
kstrtoul usage().

This addresses the case where a empty 'CHAP_I=' key value received during
mutual authentication would be converted to a '0' by simple_strtoul(),
instead of failing the login attempt.

Reported-by: Tejas Vaykole <tejas.vaykole@calsoftinc.com>
Tested-by: Tejas Vaykole <tejas.vaykole@calsoftinc.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

iscsi-target: Reject mutual authentication with reflected CHAP_C

This patch adds an explicit check in chap_server_compute_md5() to ensure
the CHAP_C value received from the initiator during mutual authentication
does not match the original CHAP_C provided by the target.

This is in line with RFC-3720, section 8.2.1:

Originators MUST NOT reuse the CHAP challenge sent by the Responder
for the other direction of a bidirectional authentication.
Responders MUST check for this condition and close the iSCSI TCP
connection if it occurs.

Reported-by: Tejas Vaykole <tejas.vaykole@calsoftinc.com>
Cc: stable@vger.kernel.org # 3.1+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

iscsi-target: Fix CHAP_A parameter list handling

The target is failing to handle list of CHAP_A key-value pair form
initiator.The target is expecting CHAP_A=5 always. In other cases,
where initiator sends list (for example) CHAP_A=6,5 target is failing
the security negotiation. Which is incorrect.

This patch handles the case (RFC 3720 section 11.1.4).
where in the initiator may send list of CHAP_A values and target replies
with appropriate CHAP_A value in response

(Drop whitespaces + rename to chap_check_algorithm + save original
pointer + add explicit check for CHAP_A key - nab)

Signed-off-by: Tejas Vaykole <tejas.vaykole@calsoftinc.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

iscsi-target: chap auth shouldn't match username with trailing garbage

In iSCSI negotiations with initiator CHAP enabled, usernames with
trailing garbage are permitted, because the string comparison only
checks the strlen of the configured username.

e.g. "usernameXXXXX" will be permitted to match "username".

Just check one more byte so the trailing null char is also matched.

Signed-off-by: Eric Seppanen <eric@purestorage.com>
Cc: <stable@vger.kernel.org> #3.1+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

target/iscsi: Remove macros that contain typecasts

These just want to return a pointer instead of a value, but are otherwise
the same.

ISCSI_TPG_LUN macro was unused.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

target: Update copyright ownership/year information to 2013

Update copyright ownership/year information for target-core,
loopback, iscsi-target, tcm_qla2xx, vhost and iser-target.

Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

target/iscsi: Remove chap_set_random()

The result from get_random_bytes should already be random, so further
manipulation and mixing should not be needed.

Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

target/iscsi: Fix mutual CHAP auth on big-endian arches

See https://bugzilla.redhat.com/show_bug.cgi?id=916290

Used a temp var since we take its address in sg_init_one.

Signed-off-by: Andy Grover <agrover@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

iscsi-target: fix chap identifier simple_strtoul usage

This patch makes chap_server_compute_md5() use proper unsigned long
usage for the CHAP_I (identifier) and check for values beyond 255 as
per RFC-1994.

Reported-by: Joern Engel <joern@logfs.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

target: remove useless casts

A reader should spend an extra moment whenever noticing a cast,
because either something special is going on that deserves extra
attention or, as is all too often the case, the code is wrong.

These casts, afaics, have all been useless. They cast a foo* to a
foo*, cast a void* to the assigned type, cast a foo* to void*, before
assigning it to a void* variable, etc.

In a few cases I also removed an additional &...[0], which is equally
useless.

Lastly I added three FIXMEs where, to the best of my judgement, the
code appears to have a bug. It would be good if someone could check
these.

Signed-off-by: Joern Engel <joern@logfs.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

iscsi-target: Fix hex2bin warn_unused compile message

Fix the following compile warning with hex2bin() usage:

drivers/target/iscsi/iscsi_target_auth.c: In function ‘chap_string_to_hex’:
drivers/target/iscsi/iscsi_target_auth.c:35: warning: ignoring return value of ‘hex2bin’, declared with attribute warn_unused_result

Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

iscsi-target: use native hex2bin for chap_string_to_hex

This patch converts chap_string_to_hex() to use hex2bin() instead of
the internal chap_asciihex_to_binaryhex().

(nab: Fix up minor compile breakage + typo)

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: "Nicholas A. Bellinger" <nab@linux-iscsi.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

iscsi-target: Add iSCSI fabric support for target v4.1

The Linux-iSCSI.org target module is a full featured in-kernel
software implementation of iSCSI target mode (RFC-3720) for the
current WIP mainline target v4.1 infrastructure code for the v3.1
kernel. More information can be found here:

http://linux-iscsi.org/wiki/ISCSI

This includes support for:

* RFC-3720 defined request / response state machines and support for
all defined iSCSI operation codes from Section 10.2.1.2 using libiscsi
include/scsi/iscsi_proto.h PDU definitions
* Target v4.1 compatible control plane using the generic layout in
target_core_fabric_configfs.c and fabric dependent attributes
within /sys/kernel/config/target/iscsi/ subdirectories.
* Target v4.1 compatible iSCSI statistics based on RFC-4544 (iSCSI MIBS)
* Support for IPv6 and IPv4 network portals in M:N mapping to TPGs
* iSCSI Error Recovery Hierarchy support
* Per iSCSI connection RX/TX thread pair scheduling affinity
* crc32c + crc32c_intel SSEv4 instruction offload support using libcrypto
* CHAP Authentication support using libcrypto
* Conversion to use internal SGl allocation with iscsit_alloc_buffs() ->
transport_generic_map_mem_to_cmd()

(nab: Fix iscsi_proto.h struct scsi_lun usage from linux-next in commit:
iscsi: Use struct scsi_lun in iscsi structs instead of u8[8])
(nab: Fix 32-bit compile warnings)

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Andy Grover <agrover@redhat.com>
Acked-by: Roland Dreier <roland@kernel.org>
Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>