neutron service user should not require admin

[Brant Knudson]

The typical config has nova using the 'neutron' user in the 'service' project to do operations against Neutron. The 'neutron' user should not require the 'admin' role on the 'service' project to do all the operations it needs to do against Neutron. Neutron's default policy.json should allow the 'neutron' user (i.e., users with the 'service' role) to do all the operations it needs to do against Neutron, rather than requiring 'admin'.

Nova is allocating networks and creating ports, so these operations need to allow the 'service' role to perform these operations, too.

[Brant Knudson (blk-u)]

Giving the neutron user the admin role gives it too much authority, and is a potential privilege escalation.

[Jeremy Stanley (fungi)]

You've switched this bug report to indicate an exploitable security vulnerability. Can you describe in greater detail the exploitation scenario you have in mind? What sort of patch to neutron do you expect to correct this defect? Does this vulnerability appear in previous releases of neutron as well, or does it only affect the current master and stable/kilo branches of neutron?

[Brant Knudson (blk-u)]

There's no way to exploit this that I know of, so this doesn't have to be a security bug... I'll change it back.