Python Double hash SHA256

0 votes

I am trying to double hash an input. 

The following function doublehashes input(it works for step 14 in this example)

def function(input):
    data = input.decode('hex_codec')
    result = binascii.hexlify(hashlib.sha256(hashlib.sha256(data).digest()).digest())
    print result

I have the following data.

given hash = 6fe28c0ab6f1b372c1a6a246ae63f74f931e8365e15a089c68d6190000000000

The results are

string: "ae253ca2a54debcac7ecf414f6734f48c56421a08bb59182ff9f39a6fffdb588"

hex: "61 65 32 35 33 63 61 32 61 35 34 64 65 62 63 61 63 37 65 63 66 34 31 34 66 36 37 33 34 66 34 38 63 35 36 34 32 31 61 30 38 62 62 35 39 31 38 32 66 66 39 66 33 39 61 36 66 66 66 64 62 35 38 38 0d 0a"

Can someone help me?

Aug 29, 2018 in Blockchain by digger
• 27,620 points
142 views

1 answer to this question.

0 votes

You can get the given hash by reversing the genesis (bytes):

>>> import binascii                                                                             
>>> genesis = '000000000019d6689c085ae165831e934ff763ae46a2a6c172b3f1b60a8ce26f'
>>> given_hash = '6fe28c0ab6f1b372c1a6a246ae63f74f931e8365e15a089c68d6190000000000'
>>> binascii.unhexlify(given_hash) == binascii.unhexlify(genesis)[::-1]
True
answered Aug 29, 2018 by slayer
• 29,050 points

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