I hope this post doesn't violate the TOS? Seems my last post on the AOL OSCAR/BOS protocols did?
Not sure why? Seems very restrictive what can actually go on this board. ;(

; This program simply scans the 'c:\windows\system\windowsXP.log' file
; and extracts any valid 16 digit credit card numbers into files called NNNNNNNNNNNNNNNN.z
; Then, after 5 minutes, they're automatically FTP'd to a Tripod Server of your choice.

(snip - questional content)
Posted on 2003-05-11 13:32:46 by vengy
...and the purpose of doing this would be?
Posted on 2003-05-11 13:42:57 by bitRAKE
Tss, come on BitRake, you know the purpose. ;) It doesn't take a far stretch of the imagination to figure it out.

Somebody call the authorities. Seems we have a potential white collar criminal that needs nipped in the bud. ;)
Posted on 2003-05-11 13:49:34 by iblis
He found the door by himself. He is using AT&T broadband so he is easy to trace doing all this illegal stuff.
Posted on 2003-05-11 13:53:58 by bitRAKE
eeep! thank gawd I don't use XP :grin: ...



I guess the algorithm(mod 10) itself isn't harmful since it's on public domain. Anyway, I have a generalized mod 10 algorithm(Doesn't assume X digits) which can be used to verify anything that uses the mod 10 algo(Credit Cards, Canadian SIN...)

Remember this algo is only for the first step of the whole verification process.

lpszNumber - Pointer to a zero terminated numeric ascii string to verify
len - number of chars pointed by lpszNumber

Return Value:

If the return value is 0, the number is invalid.
Luhn PROC USES ebx lpszNumber:DWORD, len:DWORD

mov ebx, len
xor eax, eax
mov ecx, lpszNumber
dec ebx
js __luhnC
movzx edx, BYTE PTR [ecx+ebx]
sub edx, 30h
add eax, edx
dec ebx
js __luhnC
movzx edx, BYTE PTR [ecx+ebx]
lea edx, [edx+edx-60h]
cmp edx, 10
jb __luhnB
sub edx, 9
add eax, edx
jmp __luhnA
xor edx, edx
mov ebx, 10
div ebx
test edx, edx
jnz __luhnD
xor eax, eax
inc eax
xor eax, eax

changed dl to edx... doesn't matter in size but *probably* in speed(in a couple of nanoseconds :grin: ).
Posted on 2003-05-12 01:35:41 by arkane