apport can hang when checking for ec2 metadata

data/general-hooks/ubuntu.py has something like this:
    ec2_instance = False
    for pkg in ('ec2-init', 'cloud-init'):
        try:
            if apport.packaging.get_version(pkg):
                ec2_instance = True
                break
    ...
    if ec2_instance:
        metadata_url = 'http://169.254.169.254/latest/meta-data/'
        ami_id_url = urljoin(metadata_url, 'ami-id')
        try:
            ami = urlopen(ami_id_url).read()
        except:
            ami = None

If cloud-init is installed, then it will try to do a get of http://169.254.169.254/latest/meta-data/ . In a restrictive firewall, that may be firewalled off, causing apport to appear to hang. we've actually seen this in a Canonical run datacenter where cloud-init was installed on a host system.

The problem can be remedied with:
  route add -host 169.254.169.254 reject

Then, after reporting the bug simply do:
  route del -host 169.254.169.254 reject

We should probably put a timeout on the urlopen call so that it doesn't hang indefinitely (or whatever the OS level socket timeout is, which is really large).

ProblemType: Bug
DistroRelease: Ubuntu 11.10
Package: apport 1.23-0ubuntu1
ProcVersionSignature: Ubuntu 3.0.0-11.18-server 3.0.4
Uname: Linux 3.0.0-11-server x86_64
ApportLog:

ApportVersion: 1.23-0ubuntu1
Architecture: amd64
CrashReports:
 600:0:0:13730:2011-09-20 12:15:44.651957665 -0400:2011-09-20 12:15:44.651957665 -0400:/var/crash/_usr_bin_add-apt-repository.0.crash
 775:1000:1000:4096:2011-09-19 20:46:56.988992051 -0400:2011-09-19 20:46:57.298997188 -0400:/var/crash/unpack
 600:1000:114:35637:2011-09-19 20:57:13.669684000 -0400:2011-09-19 20:59:01.801580663 -0400:/var/crash/_usr_lib_erlang_erts-5.8.3_bin_erlexec.107.crash
 600:0:0:17359:2011-09-20 17:57:45.687626739 -0400:2011-09-20 17:57:45.687626739 -0400:/var/crash/_usr_bin_nova-manage.0.crash
 600:0:0:246548:2011-09-19 22:15:29.600167786 -0400:2011-09-19 22:15:29.560167110 -0400:/var/crash/rabbitmq-server.0.crash
Date: Wed Sep 21 11:27:37 2011
PackageArchitecture: all
ProcEnviron:
 PATH=(custom, user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: apport
UpgradeStatus: No upgrade log present (probably fresh install)