Run as root on iPhone, over SSH:
(Requires iokittools, coreutils, vim)

REVISED to avoid ugly hard-coded byte offsets:

ioreg -l -w 0 | grep '"Firmware" =' | cut -d '<' -f2 | cut -d '>' -f1 | xxd -r -ps - zephyr_main.bin
ioreg -l -w 0 | grep '"A-Speed Firmware" =' | cut -d '<' -f2 | cut -d '>' -f1 | xxd -r -ps - zephyr_aspeed.bin