Unlike maps, BPF programs currently have no natural place to declare
metadata like their desired owner & group. Add a bpf_prog_def struct
to allow setting these, located in a new "progs" section, and update
bpfloader to chown pinned programs appropriately based on this
information.
Add a #DEFINE_BPF_PROG macro to simplify adding this data for
programs. The struct name is the name of the corresponding function
with "_def" appended, which bpfloader uses to correlate a bpf_map_def
with the correct program.
Also have bpfloader set mode to 0440 for all programs, since only read
access should ever be needed
Bug: 149434314
Test: load a program that uses DEFINE_BPF_PROG and check that owner &
group are set as expected
Change-Id: I914c355f114368fe53de2c7f272d877463cba461
Signed-off-by: Connor O'Brien <connoro@google.com>
3278a1634b