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 Post subject: Crc32
PostPosted: Wed May 01, 2019 1:40 pm 

Joined: Thu Aug 07, 2014 10:28 pm
Posts: 240
How do I use the crc table from Apple
https://opensource.apple.com/source/xnu ... rn/crc32.c

I am trying to get this result

Character/cc0001_b01a.apk 00000000000000000000003566186470

The initialize value should be the string length oF Character/cc0001_b01a.apk then convert the hex to dec to get the number

https://estertion.win/2019/04/%E6%98%9F ... %E6%B3%95/


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 Post subject: Re: Crc32
PostPosted: Wed May 01, 2019 2:21 pm 
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Joined: Wed Jul 30, 2014 9:32 pm
Posts: 10553
I guess the crc scanning script can help without spending time about what values to use:
http://aluigi.org/bms/crc_scan.bms

Let's do it simple :)


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 Post subject: Re: Crc32
PostPosted: Thu May 02, 2019 2:12 am 

Joined: Thu Aug 07, 2014 10:28 pm
Posts: 240
This worked is there a cleaner way to make this OPTIONS string?
Code:
set NAME string "Character/cc0001_b01a.apk"
Strlen SIZE NAME
set OPTIONS string " 32 "
string OPTIONS += SIZE
string OPTIONS += " 0 0 0 1"
encryption crc 0xedb88320 OPTIONS
string DUMMY E= NAME
print "%QUICKBMS_CRC|x%"


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 Post subject: Re: Crc32
PostPosted: Thu May 02, 2019 1:20 pm 
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Joined: Wed Jul 30, 2014 9:32 pm
Posts: 10553
So basically the initial value of the crc isn't 0 or -1 like all the algorithms but it's the same size of the string... interesting.

The only way to make it shorter would be using String 'p':
Code:
set NAME string "Character/cc0001_b01a.apk"
string OPTIONS p " 32 %d 0 0 0 1" SIZE
encryption crc 0xedb88320 OPTIONS
string DUMMY E= NAME
print "%QUICKBMS_CRC|x%"


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