Duplicating packets efficiently within a network security appliance
A network security appliance uses a switch to switch packets between cores configured for fast path processing and slow path processing. The switch duplicates packets for delivery to the slow path processing cores, eliminating the need for the fast path processing cores to expend processor resources on packet duplication. The switch can use IEEE 802.1ad Q-in-Q VLAN tags in the packet to perform the switching and packet duplication. Slow path processing cores may also broadcast packets to other slow path processing cores via the switch.
1. A non-transitory machine readable medium with instructions stored thereon, comprising instructions that when executed cause a network security appliance to:
perform in a first core fast path processing on a packet received by the network security appliance;
insert by the first core a first virtual local area network tag into the packet;
define a first virtual local area network to a switch of the network security appliance, the first virtual local area network associated with the first virtual local area network tag;
assign a first plurality of cores to the first virtual local area network associated with the first virtual local area network tag;
switch the packet from the first core to the first plurality of cores via the switch based on the first virtual local area network tag;
perform slow path processing concurrently in the first plurality of cores;
remove the first virtual local area network tag from the packet;
insert by a second core a second virtual local area network tag into the packet, wherein the second core is a member of the first plurality of cores; and
send the packet from the second core to a second plurality of cores via the switch based on the second virtual local area network tag.
2. The non-transitory machine readable medium of claim 1 , wherein the instructions stored thereon further comprise instructions that when executed cause the network security appliance to:
receive the packet by a network interface of the network security appliance;
define a second virtual local area network to the switch, the second virtual local area network associated with a second virtual local area network tag;
insert the second virtual local area network tag into the packet; and
switch the packet from the network interface to the first core via the switch based on the second virtual local area network tag.
3. The non-transitory machine readable medium of claim 2 , wherein the instructions stored thereon further comprise instructions that when executed cause the network security appliance to:
configure a switch of the network appliance to switch packets based on the first virtual local area network tag and the second virtual local area network tag.
4. The non-transitory machine readable medium of claim 1 , wherein the instructions stored thereon further comprises instructions that when executed cause the network security appliance to:
configure a switch of the network appliance to switch packets based on the first virtual local area network tag.
5. A network security appliance, comprising:
a first core;
a first plurality of cores;
a switch connected to the first core and the first plurality of cores;
a first memory connected to the first core, on which is stored instructions that when executed by the first core cause the first core to:
perform fast path processing of a packet; and
insert a first virtual local area network tag into the packet, the first virtual local area network tag identifying a first virtual local area network associated with a subplurality of the first plurality of cores;
send the packet to the switch for duplication and delivery to the first subplurality of cores; and
a second memory connected to the first plurality of cores, on which is stored instructions that when executed by the subplurality of the first plurality of cores cause the subplurality of the first plurality of cores to:
perform slow path processing of the packet concurrently;
send the packet to the switch addressed to a second subplurality of the first plurality of cores;
remove a virtual local area network tag added to the packet by the first core; and
insert a virtual local area network tag into the packet,
wherein the switch is configured to duplicate the packet received from the first core and send the duplicated packet to each of the subplurality of the first plurality of cores.
6. The network security appliance of claim 5 , wherein the switch is configured to switch packets based on a Q-in-Q virtual local area network standard.
7. The network security appliance of claim 5 , further comprising:
a network interface, connected to the first core, configured to receive the packet.
8. The network security appliance of claim 7 , wherein the network interface is connected to the first core via the switch.
9. The network security appliance of claim 8 ,
wherein the switch is configured to insert a first virtual local area network tag into the packet and switch the packet based on the first virtual local area network tag, and
wherein the first core is configured as associated with a first virtual local area network identified by the first virtual local area network tag.
10. The network security appliance of claim 5 , wherein the switch comprises a buffer memory for holding the packet while switching the packet to the subplurality of the first plurality of cores.
11. A method of processing packets in a network security appliance, comprising:
receiving a packet at a network interface;
switching the packet to a first core of the network security appliance;
performing fast path processing by the first core of the network security appliance;
determining by the first core that slow path processing should be performed by a plurality of cores of the network security appliance;
inserting by the first core a first virtual local area network tag into the packet;
sending the packet from the first core to a switch of the network security appliance;
duplicating the packet by the switch, sending each of the duplicated packets to a member of the plurality of cores for slow path processing based on the first virtual local area network tag;
performing slow path processing on the duplicated packet by the plurality of cores;
determining by a second core of the plurality of cores performing slow path processing that additional slow path processing should be performed on the packet;
inserting a second virtual local area network tag into the packet;
sending the packet from the second core to the switch;
duplicating the packet by the switch, sending the duplicated packets to a subplurality of the plurality of cores performing slow path processing based on the second virtual local area network tag; and
performing the additional slow path processing of the packet by the subplurality of the plurality of cores.
12. The method of claim 11 , further comprising:
associating the first core with a first virtual local area network; and
associating the plurality of cores with a second virtual local area network.