Re: [PATCH] crypto: eseqiv - fix IV generation for sync algorithms

[Steffen Klassert <steffen.klassert@secunet.com>]

On Wed, Apr 15, 2009 at 07:15:49PM +0800, Herbert Xu wrote:
> 
> Well caught! Clearly no one has ever tried this before :)
> 

I thought so :)

> 
> So how about doing what seqiv does and check
> 
> 	if (giv != req->giv)
> 

Yes, that's probaply the better check.
An updated patch is below.


crypto: eseqiv - fix IV generation for sync algorithms

If crypto_ablkcipher_encrypt() returns synchronous,
eseqiv_complete2() is called even if req->giv is already the
pointer to the generated IV. The generated IV is overwritten
with some random data in this case. This patch fixes this by
calling eseqiv_complete2() just if the generated IV has to be
copied to req->giv.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
---
 crypto/eseqiv.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/crypto/eseqiv.c b/crypto/eseqiv.c
index 2a342c8..3ca3b66 100644
--- a/crypto/eseqiv.c
+++ b/crypto/eseqiv.c
@@ -153,7 +153,8 @@ static int eseqiv_givencrypt(struct skcipher_givcrypt_request *req)
 	if (err)
 		goto out;
 
-	eseqiv_complete2(req);
+	if (giv != req->giv)
+		eseqiv_complete2(req);
 
 out:
 	return err;
-- 
1.5.4.2