Commit Graph

17 Commits

Author SHA1 Message Date
Herbert Xu a697690bec crypto: authenc - Avoid using clobbered request pointer
Authenc works in two stages for encryption, it first encrypts and
then computes an ICV.  The context memory of the request is used
by both operations.  The problem is that when an asynchronous
encryption completes, we will compute the ICV and then reread the
context memory of the encryption to get the original request.

It just happens that we have a buffer of 16 bytes in front of the
request pointer, so ICVs of 16 bytes (such as SHA1) do not trigger
the bug.  However, any attempt to uses a larger ICV instantly kills
the machine when the first asynchronous encryption is completed.

This patch fixes this by saving the request pointer before we start
the ICV computation.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-08-23 01:04:06 +10:00
Patrick McHardy 161613293f [CRYPTO] authenc: Fix async crypto crash in crypto_authenc_genicv()
crypto_authenc_givencrypt_done uses req->data as struct aead_givcrypt_request,
while it really points to a struct aead_request, causing this crash:

BUG: unable to handle kernel paging request at 6b6b6b6b
IP: [<dc87517b>] :authenc:crypto_authenc_genicv+0x23/0x109
*pde = 00000000
Oops: 0000 [#1] PREEMPT DEBUG_PAGEALLOC
Modules linked in: hifn_795x authenc esp4 aead xfrm4_mode_tunnel sha1_generic hmac crypto_hash]

Pid: 3074, comm: ping Not tainted (2.6.25 #4)
EIP: 0060:[<dc87517b>] EFLAGS: 00010296 CPU: 0
EIP is at crypto_authenc_genicv+0x23/0x109 [authenc]
EAX: daa04690 EBX: daa046e0 ECX: dab0a100 EDX: daa046b0
ESI: 6b6b6b6b EDI: dc872054 EBP: c033ff60 ESP: c033ff0c
 DS: 007b ES: 007b FS: 0000 GS: 0033 SS: 0068
Process ping (pid: 3074, ti=c033f000 task=db883a80 task.ti=dab6c000)
Stack: 00000000 daa046b0 c0215a3e daa04690 dab0a100 00000000 ffffffff db9fd7f0
       dba208c0 dbbb1720 00000001 daa04720 00000001 c033ff54 c0119ca9 dc852a75
       c033ff60 c033ff60 daa046e0 00000000 00000001 c033ff6c dc87527b 00000001
Call Trace:
 [<c0215a3e>] ? dev_alloc_skb+0x14/0x29
 [<c0119ca9>] ? printk+0x15/0x17
 [<dc87527b>] ? crypto_authenc_givencrypt_done+0x1a/0x27 [authenc]
 [<dc850cca>] ? hifn_process_ready+0x34a/0x352 [hifn_795x]
 [<dc8353c7>] ? rhine_napipoll+0x3f2/0x3fd [via_rhine]
 [<dc851a56>] ? hifn_check_for_completion+0x4d/0xa6 [hifn_795x]
 [<dc851ab9>] ? hifn_tasklet_callback+0xa/0xc [hifn_795x]
 [<c011d046>] ? tasklet_action+0x3f/0x66
 [<c011d230>] ? __do_softirq+0x38/0x7a
 [<c0105a5f>] ? do_softirq+0x3e/0x71
 [<c011d17c>] ? irq_exit+0x2c/0x65
 [<c010e0c0>] ? smp_apic_timer_interrupt+0x5f/0x6a
 [<c01042e4>] ? apic_timer_interrupt+0x28/0x30
 [<dc851640>] ? hifn_handle_req+0x44a/0x50d [hifn_795x]
 ...

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-05-01 18:22:28 +08:00
Herbert Xu e56dd56418 [CRYPTO] authenc: Add givencrypt operation
This patch implements the givencrypt function for authenc.  It simply
calls the givencrypt operation on the underlying cipher instead of encrypt.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:50 +11:00
Herbert Xu 9ffde35a8e [CRYPTO] authenc: Use crypto_grab_skcipher
This patch converts the authenc algorithm over to crypto_grab_skcipher
which is a prerequisite for IV generation.

This patch also changes authenc to set its ASYNC status depending on
the ASYNC status of the underlying skcipher.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:46 +11:00
Herbert Xu 7c3d703fa8 [CRYPTO] authenc: Merge common hashing code
This patch merges the common hashing code between encryption and decryption.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:38 +11:00
Herbert Xu 12dc5e62b4 [CRYPTO] authenc: Use RTA_OK to check length
This patch changes setkey to use RTA_OK to check the validity of the
setkey request.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:38 +11:00
Herbert Xu c2c61f513d [CRYPTO] authenc: Fix typo in ivsize
The ivsize should be fetched from ablkcipher, not blkcipher.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:37 +11:00
Herbert Xu 42c271c6c5 [CRYPTO] scatterwalk: Move scatterwalk.h to linux/crypto
The scatterwalk infrastructure is used by algorithms so it needs to
move out of crypto for future users that may live in drivers/crypto
or asm/*/crypto.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:32 +11:00
Herbert Xu fe70f5dfe1 [CRYPTO] aead: Return EBADMSG for ICV mismatch
This patch changes gcm/authenc to return EBADMSG instead of EINVAL for
ICV mismatches.  This convention has already been adopted by IPsec.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:32 +11:00
Herbert Xu 481f34ae75 [CRYPTO] authenc: Fix hash verification
The previous code incorrectly included the hash in the verification which
also meant that we'd crash and burn when it comes to actually verifying
the hash since we'd go past the end of the SG list.

This patch fixes that by subtracting authsize from cryptlen at the start.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:30 +11:00
Herbert Xu e236d4a89a [CRYPTO] authenc: Move enckeylen into key itself
Having enckeylen as a template parameter makes it a pain for hardware
devices that implement ciphers with many key sizes since each one would
have to be registered separately.

Since the authenc algorithm is mainly used for legacy purposes where its
key is going to be constructed out of two separate keys, we can in fact
embed this value into the key itself.

This patch does this by prepending an rtnetlink header to the key that
contains the encryption key length.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:30 +11:00
Herbert Xu 7ba683a6de [CRYPTO] aead: Make authsize a run-time parameter
As it is authsize is an algorithm paramter which cannot be changed at
run-time.  This is inconvenient because hardware that implements such
algorithms would have to register each authsize that they support
separately.

Since authsize is a property common to all AEAD algorithms, we can add
a function setauthsize that sets it at run-time, just like setkey.

This patch does exactly that and also changes authenc so that authsize
is no longer a parameter of its template.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:29 +11:00
Herbert Xu e29bc6ad0e [CRYPTO] authenc: Use or instead of max on alignment masks
Since alignment masks are always one less than a power of two, we can
use binary or to find their maximum.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:28 +11:00
Herbert Xu 332f8840f7 [CRYPTO] ablkcipher: Add distinct ABLKCIPHER type
Up until now we have ablkcipher algorithms have been identified as
type BLKCIPHER with the ASYNC bit set.  This is suboptimal because
ablkcipher refers to two things.  On the one hand it refers to the
top-level ablkcipher interface with requests.  On the other hand it
refers to and algorithm type underneath.

As it is you cannot request a synchronous block cipher algorithm
with the ablkcipher interface on top.  This is a problem because
we want to be able to eventually phase out the blkcipher top-level
interface.

This patch fixes this by making ABLKCIPHER its own type, just as
we have distinct types for HASH and DIGEST.  The type it associated
with the algorithm implementation only.

Which top-level interface is used for synchronous block ciphers is
then determined by the mask that's used.  If it's a specific mask
then the old blkcipher interface is given, otherwise we go with the
new ablkcipher interface.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:15 +11:00
Herbert Xu f347c4facf [CRYPTO] authenc: Move initialisations up to shut up gcc
It seems that newer versions of gcc have regressed in their abilities to
analyse initialisations.  This patch moves the initialisations up to avoid
the warnings.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2007-11-23 19:32:09 +08:00
Herbert Xu e4c5c6c9b0 [CRYPTO] authenc: Kill spaces in algorithm names
We do not allow spaces in algorithm names or parameters.  Thanks to Joy Latten
for pointing this out.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2007-10-10 16:55:46 -07:00
Herbert Xu 3c09f17c3d [CRYPTO] aead: Add authenc
This patch adds the authenc algorithm which constructs an AEAD algorithm
from an asynchronous block cipher and a hash.  The construction is done
by concatenating the encrypted result from the cipher with the output
from the hash, as is used by the IPsec ESP protocol.

The authenc algorithm exists as a template with four parameters:

	authenc(auth, authsize, enc, enckeylen).

The authentication algorithm, the authentication size (i.e., truncating
the output of the authentication algorithm), the encryption algorithm,
and the encryption key length.  Both the size field and the key length
field are in bytes.  For example, AES-128 with SHA1-HMAC would be
represented by

	authenc(hmac(sha1), 12, cbc(aes), 16)

The key for the authenc algorithm is the concatenation of the keys for
the authentication algorithm with the encryption algorithm.  For the
above example, if a key of length 36 bytes is given, then hmac(sha1)
would receive the first 20 bytes while the last 16 would be given to
cbc(aes).

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2007-10-10 16:55:43 -07:00