def get_username_from_cert(cert_string):
try:
gid = GID(string=cert_string)
# extract the URN in the subjectAltName
urn_str = gid.get_urn()
logger.debug("URN: %s" % urn_str)
except:
logger.warn("Failed to get certificate from string.")
logger.warn(traceback.format_exc())
return cert_string
try:
urn = URN(urn=str(urn_str))
except ValueError:
return cert_string
# check if this user is one of ours
home_urn = get_user_urn(urn.getName())
if home_urn == urn.urn_string():
username = urn.getName()
else:
username = urn_to_username(urn.urn_string())
logger.debug("Returning username %s" % username)
return username
