The CRYPTO_TFM_RES_BAD_KEY_LEN flag was apparently meant as a way to
make the ->setkey() functions provide more information about errors.
However, no one actually checks for this flag, which makes it pointless.
Also, many algorithms fail to set this flag when given a bad length key.
Reviewing just the generic implementations, this is the case for
aes-fixed-time, cbcmac, echainiv, nhpoly1305, pcrypt, rfc3686, rfc4309,
rfc7539, rfc7539esp, salsa20, seqiv, and xcbc. But there are probably
many more in arch/*/crypto/ and drivers/crypto/.
Some algorithms can even set this flag when the key is the correct
length. For example, authenc and authencesn set it when the key payload
is malformed in any way (not just a bad length), the atmel-sha and ccree
drivers can set it if a memory allocation fails, and the chelsio driver
sets it for bad auth tag lengths, not just bad key lengths.
So even if someone actually wanted to start checking this flag (which
seems unlikely, since it's been unused for a long time), there would be
a lot of work needed to get it working correctly. But it would probably
be much better to go back to the drawing board and just define different
return values, like -EINVAL if the key is invalid for the algorithm vs.
-EKEYREJECTED if the key was rejected by a policy like "no weak keys".
That would be much simpler, less error-prone, and easier to test.
So just remove this flag.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Horia Geantă <horia.geanta@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
xxhash is currently implemented as a self-contained module in /lib.
This patch enables that module to be used as part of the generic kernel
crypto framework. It adds a simple wrapper to the 64bit version.
I've also added test vectors (with help from Nick Terrell). The upstream
xxhash code is tested by running hashing operation on random 222 byte
data with seed values of 0 and a prime number. The upstream test
suite can be found at https://github.com/Cyan4973/xxHash/blob/cf46e0c/xxhsum.c#L664
Essentially hashing is run on data of length 0,1,14,222 with the
aforementioned seed values 0 and prime 2654435761. The particular random
222 byte string was provided to me by Nick Terrell by reading
/dev/random and the checksums were calculated by the upstream xxsum
utility with the following bash script:
dd if=/dev/random of=TEST_VECTOR bs=1 count=222
for a in 0 1; do
for l in 0 1 14 222; do
for s in 0 2654435761; do
echo algo $a length $l seed $s;
head -c $l TEST_VECTOR | ~/projects/kernel/xxHash/xxhsum -H$a -s$s
done
done
done
This produces output as follows:
algo 0 length 0 seed 0
02cc5d05 stdin
algo 0 length 0 seed 2654435761
02cc5d05 stdin
algo 0 length 1 seed 0
25201171 stdin
algo 0 length 1 seed 2654435761
25201171 stdin
algo 0 length 14 seed 0
c1d95975 stdin
algo 0 length 14 seed 2654435761
c1d95975 stdin
algo 0 length 222 seed 0
b38662a6 stdin
algo 0 length 222 seed 2654435761
b38662a6 stdin
algo 1 length 0 seed 0
ef46db3751d8e999 stdin
algo 1 length 0 seed 2654435761
ac75fda2929b17ef stdin
algo 1 length 1 seed 0
27c3f04c2881203a stdin
algo 1 length 1 seed 2654435761
4a15ed26415dfe4d stdin
algo 1 length 14 seed 0
3d33dc700231dfad stdin
algo 1 length 14 seed 2654435761
ea5f7ddef9a64f80 stdin
algo 1 length 222 seed 0
5f3d3c08ec2bef34 stdin
algo 1 length 222 seed 2654435761
6a9df59664c7ed62 stdin
algo 1 is xx64 variant, algo 0 is the 32 bit variant which is currently
not hooked up.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Eric Biggers