Network traffic switching for virtual machines

1. A cloud network that includes a plurality of virtual machines, a shared memory shared by the plurality of virtual machines, and a hypervisor, the cloud network comprising:

a distributed security switch to:

receive configuration information from the hypervisor,

the configuration information including a set of access mode attributes for interfaces of the plurality of virtual machines and a security policy for the plurality of virtual machines;

determine that a packet is to be directed from a source virtual machine, of the plurality of virtual machines, to a target virtual machine of the plurality of virtual machines;

identify an egress interface of the source virtual machine and an ingress interface of the target virtual machine,

the egress interface being associated with a first access mode attribute, of the set of access mode attributes, and the ingress interface being associated with a second access mode attribute of the set of access mode attributes; and

selectively route the packet, using the shared memory, based on the first access mode attribute, the second access mode attribute, and the security policy,

wherein, when selectively routing the packet, the distributed security switch is to:

broadcast the packet to a set of interfaces of the plurality of virtual machines,

 the set of interfaces including the ingress interface, and

 the set of interfaces excluding the egress interface.

2. The cloud network of claim 1 , where the distributed security switch is implemented by a particular virtual machine of the plurality of virtual machines.

3. The cloud network of claim 2 , where the particular virtual machine is the source virtual machine.

4. The cloud network of claim 1 , where the distributed security switch is further to:

obtain a set of security actions of the security policy; and

determine a particular security action, of the set of security actions, based on the first access mode attribute and the second access mode attribute; and

where the distributed security switch, when selectively routing the packet, is to:

selectively route the packet based on the first access mode attribute, the second access mode attribute, and the particular security action.

5. The cloud network of claim 4 , where the particular security action includes at least one of:

a packet dropping action,

a packet passing action,

a packet logging action,

a packet screening action, or

a packet inspection action.

6. The cloud network of claim 1 , where the set of access mode attributes includes at least one of:

an untrusted interface access mode attribute, or

a trusted interface access mode attribute.

7. The cloud network of claim 1 , where the distributed security switch, when selectively routing the packet, is to:

make the packet available in the shared memory.

8. A method, comprising:

receiving, by a switch of a cloud network, configuration information,

the configuration information identifying a set of access mode attributes for interfaces of a plurality of virtual machines of the cloud network and a security policy for the plurality of virtual machines;

determining, by the switch of the cloud network, that a packet is to be directed from a source virtual machine, of the plurality of virtual machines, to a target virtual machine of the plurality of virtual machines;

identifying, by the switch of the cloud network, one or more access mode attributes, of the set of access mode attributes, relating to the source virtual machine or the target virtual machine; and

selectively routing, by the switch of the cloud network, the packet, using shared memory shared by the source virtual machine and the target virtual machine, based on the one or more access mode attributes and the security policy,

where selectively routing the packet comprises:

switching a packet pointer corresponding to the packet from a transmit queue of an egress interface of the source virtual machine to a receive queue of an ingress interface of the target virtual machine.

9. The method of claim 8 , further comprising:

enforcing a policy action, of the security policy, on the packet; and

where selectively routing the packet comprises:

selectively routing the packet based on the policy action.

10. The method of claim 8 , where the plurality of virtual machines are guest virtual machines.

11. The method of claim 10 , where the switch of the cloud network is distributed across two or more virtual machines of the plurality of virtual machines.

12. The method of claim 8 , further comprising:

determining that the packet is not to be blocked; and

wherein selectively routing the packet comprises:

routing the packet based on determining that the packet is not to be blocked.

13. The method of claim 8 , wherein selectively routing the packet comprises:

selectively routing the packet using a hypervisor of a set of cloud networks.