Methods, systems, and computer program products for processing a packet with layered headers using a data structure that positionally relates the layered headers

A system for processing a packet, comprising:

• means for processing a first header of the packet to obtain a first protocol;
• means for reading a record from a data structure using the first protocol as a key, the record associating the first protocol with an offset in a second header of the packet;
• and
• means for processing a second header of the packet based on the offset in the second header to obtain a second protocol.

A computer program product for processing a packet, comprising:

• a computer readable program medium having computer readable program code embodied therein, the computer readable program code comprising:
• computer readable program code configured to process a first header of the packet to obtain a first protocol;
• computer readable program code configured to read a record from a data structure using the first protocol as a key, the record associating the first protocol with an offset in a second header of the packet;
• and
• computer readable program code configured to process a second header of the packet based on the offset in the second header to obtain a second protocol.

A method of processing an Internet Protocol Security (IPSec) packet, comprising:

• processing a first header of the packet to obtain a first IPSec protocol;
• reading a record from a data structure using the first protocol as a key, the record associating the first IPSec protocol with an offset in a second header of the packet and an offset to a payload of the packet;
• processing a second header of the packet based on the offset in the second header to obtain a second IPSec protocol;
• and
• processing the packet based on the offset to the payload of the packet to obtain at least one of a source and a destination port address.

A Internet Protocol Security (IPSec) packet processing system, comprising:

• means for processing a first header of the packet to obtain a first IPSec protocol;
• means for reading a record from a data structure using the first protocol as a key, the record associating the first IPSec protocol with an offset in a second header of the packet and an offset to a payload of the packet;
• means for processing a second header of the packet based on the offset in the second header to obtain a second IPSec protocol;
• and
• means for processing the packet based on the offset to the payload of the packet to obtain at least one of a source and a destination port address.

A computer program product, comprising:

• a computer readable program medium having computer readable program code embodied therein, the computer readable program code comprising:
• computer readable program code configured to process a first header of the packet to obtain a first IPSec protocol;
• computer readable program code configured to read a record from a data structure using the first protocol as a key, the record associating the first IPSec protocol with an offset in a second header of the packet and an offset to a payload of the packet;
• computer readable program code configured to process a second header of the packet based on the offset in the second header to obtain a second IPSec protocol;
• and
• computer readable program code configured to process the packet based on the offset to the payload of the packet to obtain at least one of a source and a destination port address.