1970, # results in 2 chained buffers entering decrypt node
# but leaving as simple buffer due to ICV removal (tra4)
2004, # footer+ICV will be added to 2nd buffer (tun4)
1970, # results in 2 chained buffers entering decrypt node
# but leaving as simple buffer due to ICV removal (tra4)
2004, # footer+ICV will be added to 2nd buffer (tun4)