Use hashcat with a dictionary of big words
#1
Hi,

I wanted to use hashcat to brute-force all the words in a dictionary file, and the maximum size of the words are 64 bytes.

I modified the common.h file and change the the following lines and then rebuild the code:

#define PW_MAX              128
#define PW_DICTMAX          127

But it seems that hashcat can recover only the wordlist up to size 31 bytes!
What shall I do further if I want to still use hashcat with bigger word sizes?

P.S. I need to use pure sha-1 mode (-m 100)
P.S.S. I use dictionary attack (-a 0)
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#2
Total wrong approach. If your algorithm creates 128 byte intermediate values you need to handle that inside a dedicated kernel for that algorithm.
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#3
Actually my need is to use only up to 64 bytes.
And the block size of the sha-1 is also 64 bytes. Why hashcat cannot handle to calculate the hash of words of size 31-65 bytes?
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#4
https://hashcat.net/wiki/doku.php?id=fre...ord_length
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#5
Yes, block size for sha1 is 64, but if the data part is >= 55, then it requires two calls to sha1 transform because of merkle-demgard construct.
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