Get the encryption certificate from an ADFS metadata file

getcert.py

import sys
from xml.etree import cElementTree as ET

x509s = []

def read_in():
    return ET.fromstring(sys.stdin.read())

def main():
    xml = read_in()
    for e in xml.findall(".//*[@use='signing']"):
      for x509 in e.iter("{http://www.w3.org/2000/09/xmldsig#}X509Certificate"):
        x509s.append(x509.text)
    for x in range(1, len(x509s)):
      if x509s[x] != x509s[x-1]:
        raise ValueError("x509 encryption certificates are not the same")
    print x509s[0]

    
if __name__ == '__main__':
    main()

Takes the xml file from standard in

python getcert.py < federated.xml