Hi Stephan, I tried 1 more patch. This time result is correct. Find attached patch file. Is there any side effect of this patch. Regards Harsh Jain On Mon, Oct 26, 2015 at 11:49 AM, Harsh Jain <harshjain.prof@xxxxxxxxx> wrote: > Hi Stephan, > > I also tried test program in libkcapi and it works. libkcapi opens > socket of type "hmac(sha1)" .Openssl opens multiple "sha1" type socket > and uses the partial results to calculate hmac. > > "crypto_ahash_init()" function initialises the *tfm variable in > crypto_shash structure.It gets called when user calls write() system > call. To give a try I updated the hash_accept() function and re-run. > This time kernel didn't crashed but result calculated is wrong. > > How accept() sys call decide weather to call alg_accept() or hash_accept()? > > Find attached patch and strace.Right now af_alg code is not accessible > to me. I will share it tomorrow. > > > > Thanks and Regards > Harsh jain > > On Sun, Oct 25, 2015 at 5:28 PM, Stephan Mueller <smueller@xxxxxxxxxx> wrote: >> Am Sonntag, 25. Oktober 2015, 11:56:27 schrieb Harsh Jain: >> >> Hi Harsh, >> >>>Hi, >>> >>> >>>When trying to calculate HMAC(SHA1) with openssl using af-alg engine >>>kernel crashes.Find below the command used and kernel. I have added >>>some debug print in logs. >>> >>>Command used : ./openssl dgst -engine af_alg -sha1 -hmac "key" r.txt >>>kernel version : 3.17.8 >>> >>>Initial Investigation : In shash_desc structure tfm pointer contains >>>5a5a5a5a5a5a5a5a(invalid pointer), when it triess to reference export >>>function pointer it crashes. As per my understanding tfm object should >>>have pointer of memory bloack allocated in >>>"crypto_init_shash_ops_async" function >>> >>>Please give some pointers to debug the issue.Any documentation to >>>understand the crypto-api code. >> >> May I ask you to send 2 things: the source code of the OpenSSL af_alg engine >> that you use (IIRC it is not included upstream, I want to be sure I used the >> right one). >> >> Further, can you attach an strace of the aforementioned command? >> >> Note, I am playing and abusing the AF_ALG interface for quite some time with >> [1] but I did not come across any issues like the one you describe here. >> >> [1] http://www.chronox.de/libkcapi.html >> >> Ciao >> Stephan
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algif_hash_2.patch
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