nexp-gre — Generic Routing Encapsulation (GRE) support for Network Expect
PDU definition:
gre
( [
proto
=num
,] [
cksum
] )
The following parameters allow you to define the different parts of a GRE protocol data unit (PDU) in Network Expect:
proto
=
NUMSPEC
Specifies the value of the Protocol field in the GRE header. Default: Ethertype of tunneled protocol if known; zero if unknown.
cksum
Sets the checksum flag of the GRE PDU and instructs Network Expect to compute and store the checksum in the GRE header.
The current version of Network Expect does not support the decoding of received GRE PDUs into the Tcl array variable gre.
A simple GRE packet.
ip(dst = www.netexpect.org)/gre()
A GRE packet containing a checksum:
ip(dst = www.netexpect.org)/gre(cksum)
A GRE packet containing an IP packet destined to 10.1.1.1:
ip(dst = www.netexpect.org)/gre()/ip(dst = 10.1.1.1)
A GRE packet with a specific protocol field and raw payload:
ip(dst = www.netexpect.org)/gre(proto = 0x4141)/raw('AA')