FD.io VPP
v18.01.2-1-g9b554f3
Vector Packet Processing
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This plugin is an example of how an user can create a new SRv6 LocalSID behavior by using VPP plugins with the appropiate API calls to the existing SR code.
This example plugin registers a new localsid behavior, with cli keyword 'new_srv6_localsid' which only takes one parameter, a fib-table. Upon recival of a packet, this plugin will enforce the next IP6 lookup in the specific fib-table specified by the user. (Indeed it will do the lookup in the fib_table n+1 (since for the shake of the example we increment the fib-table.)
Notice that the plugin only 'defines' a new SRv6 LocalSID behavior, but the existing SR code in VNET is the one actually instantiating new LocalSIDs. Notice that there are callback functions such that when you create or remove a LocalSID you can actually setup specific parameters through the functions in this plugin.
The current graph node uses the function 'end_srh_processing' to do the Segment Routing Endpoint behavior. Notice that it does not allow the cleanup of a Segment Routing header (as per the SRv6 behavior specs). This function is identical to the one found in /src/vnet/srv6/sr_localsid.c In case that by some other reason you want to do decapsulation, or SRH clean_up you can use the functions 'end_decaps_srh_processing' or 'end_psp_srh_processing' respectively.