Red Hat Bugzilla – Bug 977891
AMQP 1.0 would allow bypassing of authorisation and connection limits
Last modified: 2015-01-21 07:57:37 EST
Description of problem:
Version-Release number of selected component (if applicable):
Steps to Reproduce:
1. set an acl policy to restrict access to queues/exchanges in some way
2. try sending or receiving from those queues/exchanges using 0-10
3. try sending or receiving from those queues/exchanges using 1.0
1.0 connections bypass rules, 0-10 connections enforce the rules
both versions enforce the rules
The goal is to ensure that enabling AMQP 1.0 doesn't allow any existing authorisation policy to be circumvented. The existing rules are heavily influenced (distorted?) by AMQP 0-10 without directly following the that version in full. A redesign of the permissioning model to be more generic would make things more intuitive for AMQP 1.0 users, but is considered out of scope for the time being.
Link attachment (i.e. creating a sender or receiver) will always require access permission to the node in question (i.e. the queue or exchange). Generally there will be other permissions required as well.
To attach as a sender to a queue, publish permission is required for the default exchange (amq.default keyword in ACL file) with the queue name as the routing key. For a sending link to an exchange the publish permission cannot be checked on attach since the routing key is unknown at that point. This is similar to 0-10 and the publish permission will be checked (if and only if there are any publish rules) for each message (again, exactly like 0-10).
To attach as a receiver from a queue, consume permission is also required for the queue in question. To attach as a receiver from an exchange, create and consume permission will be required for the subscription queue. The name of this is chosen by the broker, but it uses the container id (which can be set as a connection option in qpid::messaging) and the link name (which can be set as the name proerty in link properties of address in qpid::messaging). In addition bind permission is required for the exchange in question. Note however that unbind permission is not required in order to detach, as that permission is implied (it will happen anyway).
In the 1.0 codepath, the properties used in checking access etc are those of the node (queue or exchange). In AMQP 0-10 by contrast the fields of the command being checked are used instead (which leads to some anomalies in my view since e.g. queue-query doesn't involve any test for autodelete, exclusive etc as would a passive declare).
Fixed upstream by https://svn.apache.org/r1496466
Also need further fix upstream for windows and rhel5: https://svn.apache.org/r1496545
This issue was tested on RHEL 6.5 x86_64 and i686 with following packages:
Issue was fixed.