在python中将md5值转换为相应的SHA1和SHA256？

Question

Here in a script I take hash as user input and based on the length I am calculating whether it is md5 or sha1 or sha256. But now the problem is convert every hash to corresponding other hashes and store in a variables.

I tried this hashlib from a StackOverflow answer.

>>> import hashlib
>>> s = 'something to hash'
>>> sb = s.encode("utf8")
>>> hashlib.md5(sb)
<md5 HASH object @ 0x7f36f5ce3440>
>>> hashlib.md5(sb).hexdigest()
'6f4815fdf1f1fd3f36ac295bf39d26b4'
>>> hashlib.sha1(sb).hexdigest()
'72668bc961b0a78bfa1633f6141bcea69ca37468'

But this solves when a text is given but in my case direct hash is given like this.

hash_value = sys.argv[1]

#print len(hash_value)
if len(hash_value) == 64:
        type_of_hash = 'sha256'
elif len(hash_value) == 40:
        type_of_hash = 'sha1'
elif len(hash_value) == 32:
        type_of_hash = 'md5'
else:
        print "Invalid Hash"

Now all I wanted to do is convert hash_value to corresponding others, suppose given input is sha256 then I need to convert the hash value to other formats.

Any suggestions on how to solve this?

Answer 1

You can't do what you want to do. To generate the 3 hashes you need to process the same input three times with different algorithms.

If any of these could be derived from the any of the others, there would be no reason to have have such algorithm because there would be no advantage in using one or the other in terms of security.

Answer 2

Below is the program that i wrote to get SHA-256 and SHA-1 from MD5 using virustotal API. Hope it helps:

 pip3 install vt-py

 import vt,pandas
    client = vt.Client("Virus Total API Key")
           
    data=pandas.read_csv("path of MD5 File ")
    
    Column1=list(data['Name of Column of MD5 File containing hashes'])
    
    with open("path of new SHA-256 file you want to create ", "a") as myfile:
    
      with open("path of new SHA-1 file you want to create", "a") as myfile2:
    
    
       for i in Column1:
        file = client.get_object("/files/{}".format(i))
        myfile.write("{}\n".format(file.sha256))
        myfile2.write("{}\n".format(file.sha1))