def authorize_using_external_server(self, request):
"""
Access authorization using an external authorization server.
The request is put in a JSON Web Token (JWT) that is signed
and includes timestamps and information about sender and receiver.
"""
ip_addr = self.sec_conf['authorization']['server_ip']
port = self.sec_conf['authorization']['server_port']
# Alternative: specify node_id/dnQualifier instead in sec_conf and create a tunnel for the
# runtime-to-runtime communication (see calvin_proto.py). Could also add node_id as "aud" (audience) in jwt payload.
authorization_server_uri = "http://%s:%d" % (ip_addr, port)
payload = {
"iss": self.node.id,
"iat": datetime.utcnow(),
"exp": datetime.utcnow() + timedelta(seconds=60),
"request": request
}
cert_conffile = _conf.get("security", "certificate_conf")
domain = _conf.get("security", "certificate_domain")
cert_conf = certificate.Config(cert_conffile, domain)
node_name = self.node.attributes.get_node_name_as_str()
private_key = certificate.get_private_key(cert_conf, node_name)
# Create a JSON Web Token signed using the node's Elliptic Curve private key.
jwt_request = jwt.encode(payload, private_key, algorithm='ES256')
# cert_name is this node's certificate filename (without file extension)
cert_name = certificate.get_own_cert_name(cert_conf, node_name)
try:
# Send request to authorization server.
response = self.request_handler.get_authorization_decision(authorization_server_uri, jwt_request, cert_name)
except Exception as e:
_log.error("Security: authorization server error - %s" % str(e))
return ("indeterminate", [])
try:
# Get authorization server certificate from disk.
# TODO: get certificate from DHT if it wasn't found on disk.
certificate_authz_server = certificate.get_other_certificate(cert_conf, node_name, response["cert_name"])
public_key_authz_server = certificate.get_public_key(certificate_authz_server)
authz_server_id = certificate_authz_server.get_subject().dnQualifier
# Decode the JSON Web Token returned from the authorization server.
# The signature is verified using the Elliptic Curve public key of the authorization server.
# Exception raised if signature verification fails or if issuer and/or audience are incorrect.
decoded = jwt.decode(response["jwt"], public_key_authz_server, algorithms=['ES256'],
issuer=authz_server_id, audience=self.node.id)
response = decoded['response']
return (response['decision'], response.get("obligations", []))
except Exception as e:
_log.error("Security: JWT decoding error - %s" % str(e))
return ("indeterminate", [])
def decode_jwt(token, sender_cert_name, node_name, node_id, actor_id=None):
"""Decode JSON Web Token"""
# Get authorization server certificate from disk.
try:
sender_certificate = certificate.get_certificate(node_name, sender_cert_name)
except Exception:
raise Exception("Certificate not found.")
sender_public_key = certificate.get_public_key(sender_certificate)
sender_node_id = sender_certificate.get_subject().dnQualifier
# The signature is verified using the Elliptic Curve public key of the sender.
# Exception raised if signature verification fails or if issuer and/or audience are incorrect.
decoded = jwt.decode(token, sender_public_key, algorithms=['ES256'],
issuer=sender_node_id, audience=node_id)
if actor_id and decoded["sub"] != actor_id:
raise # Exception raised if subject (actor_id) is incorrect.
return decoded
def decode_jwt(token, sender_cert_name, node_name, node_id, actor_id=None):
"""Decode JSON Web Token"""
# Get authorization server certificate from disk.
try:
sender_certificate = certificate.get_certificate(
node_name, sender_cert_name)
except Exception:
raise Exception("Certificate not found.")
sender_public_key = certificate.get_public_key(sender_certificate)
sender_node_id = sender_certificate.get_subject().dnQualifier
# The signature is verified using the Elliptic Curve public key of the sender.
# Exception raised if signature verification fails or if issuer and/or audience are incorrect.
decoded = jwt.decode(token,
sender_public_key,
algorithms=['ES256'],
issuer=sender_node_id,
audience=node_id)
if actor_id and decoded["sub"] != actor_id:
raise # Exception raised if subject (actor_id) is incorrect.
return decoded
def get_ca_public_key(self):
"""Return the public key from certificate"""
return certificate.get_public_key(
self.configuration["CA_default"]["certificate"])
def get_cs_public_key(self):
"""Return the public key from certificate"""
return certificate.get_public_key(self.certificate)
def get_cs_public_key(self):
"""Return the public key from certificate"""
return certificate.get_public_key(self.certificate)
def get_ca_public_key(self):
"""Return the public key from certificate"""
return certificate.get_public_key(self.configuration["CA_default"]["certificate"])
