ifconfig and route could be given a -j flag to specify a JID/name, and do a jail_attach syscall to that jail before doing any work. This would allow administrators to administrate IP addresses & routing for vnet jails that might not have these binaries available (i.e.: Linux jails)
ifconfig(8) support was added in https://cgit.freebsd.org/src/commit/sbin/ifconfig?id=7e49aa86a2824e76e9d9becf61db12066bc0d79d . route(8) support patch: https://reviews.freebsd.org/D40377
route(8) support landed in https://cgit.freebsd.org/src/commit/?id=ab4d1b73cbf8980dbe05cde7d822010042db8344 . Will merge to stable/13 in 2 weeks
^Triage: assign to committer.