openstack/placement
Code Issues Proposed changes

Change utils.vpn_ping() to return a Boolean

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vpn_ping() is used exlusively to tell if a vpn server is actually
listening. The session_id it picks is not sensitive. It is just using
the session_id to make sure that the packet it receives back is a
response to the packet it sends so that it can measure latency and
tell that the server is up.

Also the tests in test_cloudpipe.py are already treating the return
value as Boolean.  Lets make it explicit.

Change-Id: I2a1d98b5fb3c9c02a4161c6df2473e091442d01d
Closes-Bug: #1420457
This commit is contained in:
Tony Breeds
2015-02-18 09:34:57 +11:00
parent 87ca38f215
commit fb610461f3
1 changed files with 5 additions and 3 deletions
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8
nova/utils.py
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@@ -135,7 +135,8 @@ SM_INHERITABLE_KEYS = (
def vpn_ping(address, port, timeout=0.05, session_id=None):
"""Sends a vpn negotiation packet and returns the server session.
Returns False on a failure. Basic packet structure is below.
Returns Boolean indicating whether the vpn_server is listening.
Basic packet structure is below.
Client packet (14 bytes)::
@@ -159,6 +160,8 @@ def vpn_ping(address, port, timeout=0.05, session_id=None):
bit 9 was 1 and the rest were 0 in testing
"""
# NOTE(tonyb) session_id isn't used for a real VPN connection so using a
# cryptographically weak value is fine.
if session_id is None:
session_id = random.randint(0, 0xffffffffffffffff)
sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
@@ -178,8 +181,7 @@ def vpn_ping(address, port, timeout=0.05, session_id=None):
dict(exp=struct.calcsize(fmt), act=len(received)))
return False
(identifier, server_sess, client_sess) = struct.unpack(fmt, received)
if identifier == 0x40 and client_sess == session_id:
return server_sess
return (identifier == 0x40 and client_sess == session_id)
def _get_root_helper():