
Date: Fri, 6 Jan 2012 17:51:20 +0530 From: Piyush Mittal <piyush.cse29@...il.com> To: johndev@...ts.openwall.com Subject: Re: Bit slice implementation of DES based hashes Hello, > In DES_bs_crypt_LM(), DES initial permutation has been preapplied to > the constant initial block. > Extremely sorry to say but I am not getting how initial permutation is calculated? What I am doing is as follows: 1.The binary conversion of KGS!@... is 01001011 01000111 01010011 00100001 01000000 00100011 00100100 00100101 2.Initial permutation array that I am using is as follows static unsigned char DES_IP[64] = { 57, 49, 41, 33, 25, 17, 9, 1, 59, 51, 43, 35, 27, 19, 11, 3, 61, 53, 45, 37, 29, 21, 13, 5, 63, 55, 47, 39, 31, 23, 15, 7, 56, 48, 40, 32, 24, 16, 8, 0, 58, 50, 42, 34, 26, 18, 10, 2, 60, 52, 44, 36, 28, 20, 12, 4, 62, 54, 46, 38, 30, 22, 14, 6 }; 3.Now the block are initialised as follows DES_bs_set_block_8(0, zero, zero, zero, zero, zero, zero, zero, zero); > DES_bs_set_block_8(8, ones, ones, ones, zero, ones, zero, zero, zero); > DES_bs_set_block_8(16, zero, zero, zero, zero, zero, zero, zero, ones); > DES_bs_set_block_8(24, zero, zero, ones, zero, zero, ones, ones, ones); > DES_bs_set_block_8(32, zero, zero, zero, ones, zero, ones, ones, ones); > DES_bs_set_block_8(40, zero, zero, zero, zero, zero, ones, zero, zero); > DES_bs_set_block_8(48, ones, ones, zero, zero, zero, zero, ones, zero); > DES_bs_set_block_8(56, ones, zero, ones, zero, ones, ones, ones, ones); > i.e 0000000011101000000000010010011100010111000001001100001010101111 but I am not getting the same sequence. What am I missing ? On Thu, Jan 5, 2012 at 6:31 PM, Solar Designer <solar@...nwall.com> wrote: > Hi Piyush, > > On Thu, Jan 05, 2012 at 06:03:37PM +0530, Piyush Mittal wrote: > > Though I searched a lot about how blocks in DES_bs_crypt_LM() are > > initialised but I am not getting sufficient idea. According to me the > > string "KGS!@..." is initialised in these blocks but the order of these > 64 > > binary bits is some what confusing. As I can't ignore this order of bits > > for oracle bit slice implementation. Can you please tell me how order is > > taken here? > > In DES_bs_crypt_LM(), DES initial permutation has been preapplied to > the constant initial block. > > Alexander >  Piyush Mittal [ CONTENT OF TYPE text/html SKIPPED ]
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