petterreinholdtsen
commented
5 years ago Here is an example to show what I try to do:
#!/usr/bin/python3
import pyasn1.codec.der
import rfc3161ng
class Test(object):
def get_stamper(self):
certificate_data = self.fetch('https://freetsa.org/files/tsa.crt')
#ca_data = self.fetch('https://freetsa.org/files/cacert.pem')
return rfc3161ng.RemoteTimestamper('http://freetsa.org/tsr',
certificate=certificate_data)
def fetch(self, url):
import urllib.request
response = urllib.request.urlopen(url)
return response.read()
def runtest(self):
timestamper = self.get_stamper()
data = b"Hello world"
tsr = timestamper(data=data, return_tsr=True)
stamp = pyasn1.codec.der.encoder.encode(tsr)
# stamp content can be written and checked by openssl ts
# Trying to check it myself
tsr2 = pyasn1.codec.der.decoder.decode(stamp)
if tsr != tsr2:
print("back and forth did not gave the same result")
res = timestamper.check(tsr, data=data)
print("Check returned", res)
if '__main__' == __name__:
t = Test()
t.runtest()
trbs
bdauvergne
Hi,
Thank you very much for documenting how to save timestamps that can be validated by openssl ts. I wonder, is it possible to use this library to go the other way, ie validate timestamps generated by openssl ts? I've tried decoding them using pyasn1.codec.der.decoder.decode(), but check() refuses the resulting stamp. :(