Re: [openssl-users] Extra bytes before the decrypted data.

2013-03-08 Thread Erwann Abalea 

It's probably the IV.

--
Erwann ABALEA

Le 08/03/2013 16:55, Tayade, Nilesh a écrit :

On performing the AES128 decryption, I see the decrypted data is preceded by a 
block of 16bytes.
E.g. Below, 0x48 to 0x5a is the extra 16bytes block. And the actual 'GET' 
request starts from 0x47 onwards.

48 3f c4 99 fa f0 75 0e 51 b8 3b 58 aa 1f 4a 5a
47 45 54 20 2f 20 48 54 54 50 2f 31 2e 31 0d 0a
...
5b 28 c4 52 4e f9 53 2c 08 04 94 04 04 04 04 04

There is a padding of 5bytes in the end, which I can detect. Any pointers on 
how to detect the initial 16bytes block?
This causes the output to be some junk followed by actual data.

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RE: [openssl-users] Extra bytes before the decrypted data.

2013-03-08 Thread Tayade, Nilesh 
 -Original Message-
 From: Erwann Abalea [mailto:erwann.aba...@keynectis.com]
 Sent: Friday, March 08, 2013 9:44 PM
 To: openssl-users@openssl.org
 Cc: Tayade, Nilesh
 Subject: Re: [openssl-users] Extra bytes before the decrypted data.
 
 It's probably the IV.

Yes, it can be IV.
But I am trying to understand why it doesn't show IV in every other data I'm 
decrypting.
And only for below specific data it shows IV preceding the decrypted contents.

 --
 Erwann ABALEA
 
 Le 08/03/2013 16:55, Tayade, Nilesh a écrit :
  On performing the AES128 decryption, I see the decrypted data is
 preceded by a block of 16bytes.
  E.g. Below, 0x48 to 0x5a is the extra 16bytes block. And the actual
 'GET' request starts from 0x47 onwards.
 
  48 3f c4 99 fa f0 75 0e 51 b8 3b 58 aa 1f 4a 5a
  47 45 54 20 2f 20 48 54 54 50 2f 31 2e 31 0d 0a
  ...
  5b 28 c4 52 4e f9 53 2c 08 04 94 04 04 04 04 04
 
  There is a padding of 5bytes in the end, which I can detect. Any
 pointers on how to detect the initial 16bytes block?
  This causes the output to be some junk followed by actual data.
__
OpenSSL Project http://www.openssl.org
User Support Mailing Listopenssl-users@openssl.org
Automated List Manager   majord...@openssl.org