[dm-crypt] What am I missing for aes-cbc-plain

[dm-crypt] What am I missing for aes-cbc-plain

[Jan Willies]

[-- Attachment #1: Type: text/plain, Size: 3364 bytes --]

Hi there,

I have stared at it long enough, and still can't make out what's missing.

I'm trying to mount an aes-cbc-plain encrypted disk with cryptsetup-1.3.0 on
kernel-2.6.37.6:

root@dockstar:~# cryptsetup luksOpen /dev/sda2 storage
Enter passphrase for /dev/sda2:
device-mapper: reload ioctl failed: No such file or directory
Failed to setup dm-crypt key mapping for device /dev/sda2.
Check that kernel supports aes-cbc-plain cipher (check syslog for more
info).
Failed to read from key storage.

May 17 15:34:27 dockstar kern.err kernel: device-mapper: table: 254:0:
crypt: Error allocating crypto tfm
May 17 15:34:27 dockstar kern.warn kernel: device-mapper: ioctl: error
adding target to table


According to /proc/crypto aes-cbc should be working correctly:

root@dockstar:~# cat /proc/crypto
name         : sha1
driver       : sha1-generic
module       : sha1_generic
priority     : 0
refcnt       : 1
selftest     : passed
type         : shash
blocksize    : 64
digestsize   : 20

name         : hmac(sha1)
driver       : mv-hmac-sha1
module       : mv_cesa
priority     : 300
refcnt       : 1
selftest     : passed
type         : ahash
async        : yes
blocksize    : 64
digestsize   : 20

name         : sha1
driver       : mv-sha1
module       : mv_cesa
priority     : 300

refcnt       : 1
selftest     : passed
type         : ahash
async        : yes
blocksize    : 64
digestsize   : 20

name         : cbc(aes)
driver       : mv-cbc-aes
module       : mv_cesa
priority     : 300
refcnt       : 1
selftest     : passed
type         : ablkcipher
async        : yes
blocksize    : 16
min keysize  : 16
max keysize  : 32
ivsize       : 16
geniv        : <default>

name         : ecb(aes)
driver       : mv-ecb-aes
module       : mv_cesa
priority     : 300
refcnt       : 1
selftest     : passed
type         : ablkcipher
async        : yes
blocksize    : 16
min keysize  : 16
max keysize  : 32
ivsize       : 0
geniv        : <default>

name         : aes
driver       : aes-generic
module       : aes_generic
priority     : 100
refcnt       : 1
selftest     : passed
type         : cipher
blocksize    : 16
min keysize  : 16
max keysize  : 32

name         : crc32c
driver       : crc32c-generic
module       : crc32c
priority     : 100
refcnt       : 2
selftest     : passed
type         : shash
blocksize    : 1
digestsize   : 4


root@dockstar:~# lsmod
aead                    3340  1 cryptomgr
aes_generic            33156  1 mv_cesa
cbc                     1656  0
crc32c                  1960  1
crypto_algapi           8412  7
mv_cesa,cbc,aes_generic,crypto_blkcipher,cryptomgr,aead,crypto_hash
crypto_blkcipher        8701  3 dm_crypt,mv_cesa,cbc
crypto_hash             7260  4 sha1_generic,mv_cesa,libcrc32c,crc32c
cryptomgr               1732  0
dm_crypt                9944  0
dm_log                  6676  2 dm_mirror,dm_region_hash
dm_mirror              10520  0
dm_mod                 43952  3 dm_crypt,dm_mirror,dm_log
dm_region_hash          4852  1 dm_mirror
mv_cesa                 7380  0
sha1_generic            1232  0


root@dockstar:~# cryptsetup luksDump /dev/sda2
LUKS header information for /dev/sda2

Version:        1
Cipher name:    aes
Cipher mode:    cbc-plain
Hash spec:      sha1
Payload offset: 2056
MK bits:        256
MK digest:      6a [...]

Key Slot 0: ENABLED
        [...]


Thanks for any pointers,

Jan

[-- Attachment #2: Type: text/html, Size: 5025 bytes --]

Re: [dm-crypt] What am I missing for aes-cbc-plain

[Milan Broz]

On 05/17/2011 04:21 PM, Jan Willies wrote:
> Hi there,
> 
> I have stared at it long enough, and still can't make out what's missing.
> 
> I'm trying to mount an aes-cbc-plain encrypted disk with cryptsetup-1.3.0 on kernel-2.6.37.6:
> 
> root@dockstar:~# cryptsetup luksOpen /dev/sda2 storage
> Enter passphrase for /dev/sda2: 
> device-mapper: reload ioctl failed: No such file or directory
> Failed to setup dm-crypt key mapping for device /dev/sda2.
> Check that kernel supports aes-cbc-plain cipher (check syslog for more info).
> Failed to read from key storage.

Please run cryptsetup with --debug and post full output.

I would also try to blacklist Marvell hw accelerator module (mv_cesa) and try
to use generic aes crypto modules.
(All this seems to me like bug in this crypto driver).

Milan

Re: [dm-crypt] What am I missing for aes-cbc-plain

[Jan Willies]

[-- Attachment #1: Type: text/plain, Size: 3233 bytes --]

Hi Milan,

2011/5/17 Milan Broz <mbroz@redhat.com>

>
> On 05/17/2011 04:21 PM, Jan Willies wrote:
> > Hi there,
> >
> > I have stared at it long enough, and still can't make out what's missing.
> >
> > I'm trying to mount an aes-cbc-plain encrypted disk with cryptsetup-1.3.0
> on kernel-2.6.37.6:
> >
> > root@dockstar:~# cryptsetup luksOpen /dev/sda2 storage
> > Enter passphrase for /dev/sda2:
> > device-mapper: reload ioctl failed: No such file or directory
> > Failed to setup dm-crypt key mapping for device /dev/sda2.
> > Check that kernel supports aes-cbc-plain cipher (check syslog for more
> info).
> > Failed to read from key storage.
>
> Please run cryptsetup with --debug and post full output.
>

Here's the output:

root@dockstar:~# cryptsetup --debug luksOpen /dev/sda2 storage
# cryptsetup 1.3.0 processing "cryptsetup --debug luksOpen /dev/sda2
storage"
# Running command luksOpen.
# Locking memory.
# Allocating crypt device /dev/sda2 context.
# Trying to open and read device /dev/sda2.
# Initialising device-mapper backend, UDEV is disabled.
# Detected dm-crypt version 1.7.0, dm-ioctl version 4.18.0.
# Trying to load LUKS1 crypt type from device /dev/sda2.
# Initialising gcrypt crypto backend.
# Reading LUKS header of size 1024 from device /dev/sda2
# Timeout set to 0 miliseconds.
# Password retry count set to 3.
# Iteration time set to 1000 miliseconds.
# Activating volume storage [keyslot -1] using [none] passphrase.
# dm status storage  OF   [16384]
# Interactive passphrase entry requested.
Enter passphrase for /dev/sda2:
# Trying to open key slot 0 [ACTIVE_LAST].
# Reading key slot 0 area.
# DM-UUID is CRYPT-TEMP-temporary-cryptsetup-2022
# dm create temporary-cryptsetup-2022 CRYPT-TEMP-temporary-cryptsetup-2022
OF   [16384]
# dm reload temporary-cryptsetup-2022  OF   [16384]
device-mapper: reload ioctl failed: No such file or directory
# dm remove temporary-cryptsetup-2022  OF   [16384]
# temporary-cryptsetup-2022: Stacking NODE_DEL (replaces other stacked ops)
Failed to setup dm-crypt key mapping for device /dev/sda2.
Check that kernel supports aes-cbc-plain cipher (check syslog for more
info).
Failed to read from key storage.
# Releasing crypt device /dev/sda2 context.
# Releasing device-mapper backend.
# Unlocking memory.
Command failed with code 5: Failed to read from key storage.


> I would also try to blacklist Marvell hw accelerator module (mv_cesa) and
> try
> to use generic aes crypto modules.
> (All this seems to me like bug in this crypto driver).


When blacklisting mv_cesa, I only get

root@dockstar:~# cat /proc/crypto
name         : sha1
driver       : sha1-generic
module       : sha1_generic
priority     : 0
refcnt       : 1
selftest     : passed
type         : shash
blocksize    : 64
digestsize   : 20

name         : aes
driver       : aes-generic
module       : aes_generic
priority     : 100
refcnt       : 1
selftest     : passed
type         : cipher
blocksize    : 16
min keysize  : 16
max keysize  : 32

name         : crc32c
driver       : crc32c-generic
module       : crc32c
priority     : 100
refcnt       : 2
selftest     : passed
type         : shash
blocksize    : 1
digestsize   : 4

although aes_generic and cbc are loaded.


regards,

Jan

[-- Attachment #2: Type: text/html, Size: 4638 bytes --]

Re: [dm-crypt] What am I missing for aes-cbc-plain

[Milan Broz]

On 05/17/2011 04:54 PM, Jan Willies wrote:
> # DM-UUID is CRYPT-TEMP-temporary-cryptsetup-2022
> # dm create temporary-cryptsetup-2022 CRYPT-TEMP-temporary-cryptsetup-2022 OF   [16384]
> # dm reload temporary-cryptsetup-2022  OF   [16384]
> device-mapper: reload ioctl failed: No such file or directory

There is something strange on your system - either some kernel modules are missing
or something similar. Any other messages in syslog?

According to used mv_cesa module I guess it is some ARM platform, right?

Maybe try to keep LUKS from the picture and check modes works, just
use plain crypt - like this:

echo "password" | cryptsetup create tst /dev/<some dev> -c aes-cbc-plain -s 128
cryptsetup remove tst

Does it fail for all combination of modes?
(Try aes-ecb - it is insecure, but just to test if aes driver works).

If it still fails with "No such file or directory", try some simple device-mapper
target using the same device:

dmsetup create tst --table "0 1000 linear /dev/sda2 0"
dmsetup remove tst

Does this work?

Milan

Re: [dm-crypt] What am I missing for aes-cbc-plain

[Jan Willies]

[-- Attachment #1: Type: text/plain, Size: 1445 bytes --]

2011/5/17 Milan Broz <mbroz@redhat.com>

> On 05/17/2011 04:54 PM, Jan Willies wrote:
> > # DM-UUID is CRYPT-TEMP-temporary-cryptsetup-2022
> > # dm create temporary-cryptsetup-2022
> CRYPT-TEMP-temporary-cryptsetup-2022 OF   [16384]
> > # dm reload temporary-cryptsetup-2022  OF   [16384]
> > device-mapper: reload ioctl failed: No such file or directory
>
> There is something strange on your system - either some kernel modules are
> missing
> or something similar. Any other messages in syslog?
>

No, unfortunately not.


> According to used mv_cesa module I guess it is some ARM platform, right?
>

Exactly.


> Maybe try to keep LUKS from the picture and check modes works, just
> use plain crypt - like this:
>
> echo "password" | cryptsetup create tst /dev/<some dev> -c aes-cbc-plain -s
> 128
> cryptsetup remove tst
>

root@OpenWrt:/# echo "password" | cryptsetup create tst /dev/sda1 -c
aes-cbc-pla
in -s 128
device-mapper: table: 254:0: crypt: Error allocating crypto tfm
device-mapper: ioctl: error adding target to table
device-mapper: reload ioctl failed: No such file or directory


> Does it fail for all combination of modes?
> (Try aes-ecb - it is insecure, but just to test if aes driver works).
>

That seems to work:

root@OpenWrt:/# echo "password" | cryptsetup create tst /dev/sda1 -c aes-ecb
-s
128
root@OpenWrt:/# cryptsetup remove tst

hm, so the aes driver works but not in combination with aes-cbc?


regards,

Jan

[-- Attachment #2: Type: text/html, Size: 2442 bytes --]

Re: [dm-crypt] What am I missing for aes-cbc-plain

[Jan Willies]

[-- Attachment #1: Type: text/plain, Size: 677 bytes --]

2011/5/17 Jan Willies <jan@willies.info>

>  Maybe try to keep LUKS from the picture and check modes works, just
>
>> use plain crypt - like this:
>>
>> echo "password" | cryptsetup create tst /dev/<some dev> -c aes-cbc-plain
>> -s 128
>> cryptsetup remove tst
>>
>
> root@OpenWrt:/# echo "password" | cryptsetup create tst /dev/sda1 -c
> aes-cbc-pla
> in -s 128
> device-mapper: table: 254:0: crypt: Error allocating crypto tfm
> device-mapper: ioctl: error adding target to table
> device-mapper: reload ioctl failed: No such file or directory
>

It works now, I was missing the module 'chainiv'.

Could the error message somehow be improved to reflect that?


regards,

jan

[-- Attachment #2: Type: text/html, Size: 1309 bytes --]