Commit ad79cdd7 authored Dec 17, 2008 by Jarod Wilson Committed by Herbert Xu Dec 25, 2008

crypto: des3_ede - permit weak keys unless REQ_WEAK_KEY set



While its a slightly insane to bypass the key1 == key2 ||
key2 == key3 check in triple-des, since it reduces it to the
same strength as des, some folks do need to do this from time
to time for backwards compatibility with des.

My own case is FIPS CAVS test vectors. Many triple-des test
vectors use a single key, replicated 3x. In order to get the
expected results, des3_ede_setkey() needs to only reject weak
keys if the CRYPTO_TFM_REQ_WEAK_KEY flag is set.

Also sets a more appropriate RES flag when a weak key is found.

Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

parent bd9d20db

crypto/des_generic.c

+3 −2

Original line number	Diff line number	Diff line
		@@ -868,9 +868,10 @@ static int des3_ede_setkey(struct crypto_tfm tfm, const u8 key,
		u32 *flags = &tfm->crt_flags;

		if (unlikely(!((K[0] ^ K[2]) \| (K[1] ^ K[3])) \|\|
		!((K[2] ^ K[4]) \| (K[3] ^ K[5]))))
		!((K[2] ^ K[4]) \| (K[3] ^ K[5]))) &&
		(*flags & CRYPTO_TFM_REQ_WEAK_KEY))
		{
		*flags \|= CRYPTO_TFM_RES_BAD_KEY_SCHED;
		*flags \|= CRYPTO_TFM_RES_WEAK_KEY;
		return -EINVAL;
		}

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