Unwrap gov.il signed documents

unsign.py

from base64 import b64decode
from os import listdir
from sys import argv
from xml.dom.minidom import parse

def unsign(filenames):
    for f in filenames:
        try:
            dom = parse(f)
        except IOError:
            print('File %s not found' % f)
            continue

        docid = f.split('.')[0]
        signed_info = dom.getElementsByTagName('gov.il:SignedInfo')[0]
        
        data = signed_info.childNodes[0].childNodes[0].data
        orig_filename = signed_info.childNodes[1].childNodes[0].childNodes[0].data

        outfile = '[%s] %s' % (docid, orig_filename)
        with open(outfile, 'wb') as out:
            out.write(b64decode(data))

if __name__ == '__main__':
    if len(argv) < 2:
        print('Usage: python unsign.py <filename> [filename] ...')
        exit(-1)
    unsign(argv[1:])