bash 双hash算法sha256的写法

这样是不行的

echo -n "hello" | sha256sum | sha256sum

因为sha256sum的输出有干扰内容

ppl@de:~/tmp$ echo -n "hello" | sha256sum
2cf24dba5fb0a30e26e83b2ac5b9e29e1b161e5c1fa7425e73043362938b9824  -

需要这样子

echo -n "hello" | sha256sum | xxd -r -p | sha256sum

python算法：

#!/usr/bin/env python3

import sys, hashlib, binascii

filename=sys.argv[1]
f = open(filename, 'r')
for line in f:
  line = line.replace('\n', '').replace('\r', '')
  round1hex = hashlib.sha256(line.encode('utf-8')).hexdigest().zfill(64)
  round1bin = binascii.unhexlify(round1hex)
  round2hex = hashlib.sha256(round1bin).hexdigest().zfill(64)
  print(round2hex)

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