Hi,
would anyone mind if I dropped ECDSA224 support from the bootloader?
Here are the size comparisons:
targets/boot_nrf52
app=@apache-mynewt-core/apps/boot
bsp=@apache-mynewt-core/hw/bsp/nrf52dk
build_profile=optimized
syscfg=TIMER_0=0:UART_0=0
with ECDSA256:
objsize
text data bss dec hex filename
10816 352 4376 15544 3cb8
/Users/marko/src2/incubator-mynewt-blinky/bin/targets/boot_nrf52/app/apps/boot/boot.elf
with ECDSA224:
objsize
text data bss dec hex filename
23368 144 4376 27888 6cf0
/Users/marko/src2/incubator-mynewt-blinky/bin/targets/boot_nrf52/app/apps/boot/boot.elf
with RSA:
objsize
text data bss dec hex filename
15288 60 4376 19724 4d0c
/Users/marko/src2/incubator-mynewt-blinky/bin/targets/boot_nrf52/app/apps/boot/boot.elf
For ECSDA256 I’m using the tinycrypt implementation, and this appears to
make the whole thing somewhat smaller.
Given that both are using curves coming from same source, we probably
wouldn’t lose much by dropping the shorter key version.
Unless, of course, someone is already using that. In which we should keep it.
