Skip to content
Eddie Kohler edited this page Oct 17, 2017 · 1 revision

IPGWOptions Element Documentation

NAME

IPGWOptions — Click element; processes router IP options

SYNOPSIS

IPGWOptions(MYADDR [, OTHERADDRS])

Ports: 1 input, 1-2 outputs
Processing: agnostic, but output 1 is push

DESCRIPTION

Process the IP options that should be processed by every router, not just when ip_dst refers to the current router. At the moment that amounts to Record Route and Timestamp (in particular, not the source route options). MYADDR is the router's IP address on the interface downstream from the element.

Probably needs to be placed on the output path, since MYADDR must be the outgoing interface's IP address (rfc1812 4.2.2.2).

Recomputes the IP header checksum if it modifies the packet.

The optional OTHERADDRS argument should be a space-separated list of IP addresses containing the router's other interface addresses. It is used to implement the Timestamp option.

The second output may be connected to an ICMPError to produce a parameter problem (type=12,code=0) message. IPGWOptions sets the param_off packet annotation so that ICMPError can set the Parameter Problem pointer to point to the erroneous byte.

SEE ALSO

ICMPError

Generated by click-elem2man from ../elements/ip/ipgwoptions.hh:8 on 2017/10/17.

Clone this wiki locally