Re: CIPHER'n problem

["Keith Carpenter" <CarpCon@xxxxxxx>]

Not sure if this is your error, but you've specified a 32 byte (256 bit) key
length.  If as you suggest your system only supports AES with a key length
of 128 bits, try using the 16 byte key.


Keith


----- Original Message ----- 
From: "Haas, Matt" <Matt.Haas@xxxxxxxxxxx>
To: "RPG-L (E-mail)" <rpg400-l@xxxxxxxxxxxx>
Sent: Monday, October 04, 2004 5:15 PM
Subject: CIPHER'n problem


> Here's the background on the problem I'm having:
>
> For an upcoming project, I need to store some encrypted data in a cookie
which has me looking at using the CIPHER MI instruction to do this. I
started by looking at a few examples that do an MD5 hash (which doesn't work
for me since I need to decrypt it) and, of course, Scott Klement's RC4
example. I did a little bit of research into using RC4 and it looks like
it's easy to make implementation mistakes that reduce it's security so I'm
wanting to use something better (or at least not as easy to screw up),
specifically, I want to use AES.
>
> I spent a little bit of time working on this today but I'm getting this
error when I run my program: "Requested function not valid or is not
available on the machine.". To double check what's installed, I ran Scott's
program that lists the installed ciphers and 128 bit AES was listed. I know
the crypto providers are installed and we're on V5R1. Anyone have any ideas?
>
> Here's the code:
>
>      H DFTACTGRP(*NO) BNDDIR('QC2LE') option(*SRCSTMT: *NODEBUGIO)
>      H ACTGRP(*NEW)
>
>      Dcipher           PR                  extproc('_CIPHER')
>      D receiver                        *
>      D control                       96A
>      D source                          *
>
>      DAES_Controls     DS
>      D FunctionID                     2A
>      D DataLen                        5U 0
>      D Operation                      1A
>      D Mode                           1A
>      D BlockLength                    3U 0
>      D MAClength                      3U 0
>      D InitVector                    32A
>      D Reserved                       7A
>      D KeyOption                      1A
>      D KeySchedulePtr                  *
>      D Key                           32A
>
>      DKeySchedule      S           1088A
>      DOP_ENCRYPT       C                   const(x'00')
>      DOP_DECRYPT       C                   const(x'01')
>      DOP_MAC           C                   const(x'02')
>      DMODE_ECB         C                   const(x'00')
>      DMODE_CBC         C                   const(x'01')
>      DKEYOPT_SCHEDULE  C                   const(x'00')
>      DKEYOPT_16BYTE    C                   const(x'10')
>      DKEYOPT_24BYTE    C                   const(x'18')
>      DKEYOPT_32BYTE    C                   const(x'20')
>      DFUNCID_AES       C                   const(x'0015')
>
>      DTestData         S             32A   inz('Secret Text!')
>      DEncrypted        S             20A
>      DPassword         S             32A   inz('My Password 123')
>      Dp_recv           s               *
>      Dp_src            s               *
>      Ddalen            s             10I 0
>
>       /free
>           AES_Controls = *ALLx'00';
>           dalen=%size(aes_controls);
>           dalen=%len(aes_controls);
>           FunctionID = FUNCID_AES;
>           DataLen = %len(TestData);
>           Operation = OP_ENCRYPT;
>           Mode = MODE_ECB;
>           BlockLength = 32;
>           KeyOption = KEYOPT_32BYTE;
>           KeySchedulePtr = %addr(KeySchedule);
>           Key = Password;
>
>           p_recv = %addr(Encrypted);
>           p_src  = %addr(TestData);
>
>           cipher( p_recv: AES_Controls: p_src);
>
>           *inLR = *ON;
>       /end-free
>
> Thanks,
>
> Matt
>
> --
> This is the RPG programming on the AS400 / iSeries (RPG400-L) mailing list
> To post a message email: RPG400-L@xxxxxxxxxxxx
> To subscribe, unsubscribe, or change list options,
> visit: http://lists.midrange.com/mailman/listinfo/rpg400-l
> or email: RPG400-L-request@xxxxxxxxxxxx
> Before posting, please take a moment to review the archives
> at http://archive.midrange.com/rpg400-l.
>