BITHD Firmware

https://bithd.com/

How to build BITHD firmware?

1. Install Docker
2. git clone https://github.com/bithd/bithd-mcu.git
3. cd bithd-mcu
4. export TAG=v2.7.4; ./build-firmware.sh $TAG (where TAG is v2.7.4 for example)
5. pipenv --python 3 install (set up pipenv)
6. pipenv run ./script/prepare_firmware.py -f ./build/bithd-$TAG-unsigned.bin (prepare the image to sign)

This creates file build/bithd-$TAG-unsigned.bin and prints its fingerprint and size at the end of the build log.

How to build BITHD bootloader?

1. Install Docker
2. git clone https://github.com/bithd/bithd-mcu.git
3. cd bithd-mcu
4. ./build-bootloader.sh TAG (where TAG is bl1.3.2 for example)

This creates file build/bootloader-TAG.bin and prints its fingerprint and size at the end of the build log.

Verify signed image exported from App

1. Get the same version signed firmware image exported from App
2. Compare the unsigned and signed image files, eg v2.7.4

export TAG=v2.7.4
diff <(xxd build/bithd-$TAG-prepared.bin) <(xxd build/bithd-$TAG-signed.bin)

The following is the comparison result for v2.7.4. The only differences are the first 256 bytes that the signed image has the signatures.

1c1
< 00000000: 5452 5a52 9433 0600 0000 0001 0000 0000  TRZR.3..........
---
> 00000000: 5452 5a52 9433 0600 0304 0501 0000 0000  TRZR.3..........
5,16c5,16
< 00000040: 0000 0000 0000 0000 0000 0000 0000 0000  ................
< 00000050: 0000 0000 0000 0000 0000 0000 0000 0000  ................
< 00000060: 0000 0000 0000 0000 0000 0000 0000 0000  ................
< 00000070: 0000 0000 0000 0000 0000 0000 0000 0000  ................
< 00000080: 0000 0000 0000 0000 0000 0000 0000 0000  ................
< 00000090: 0000 0000 0000 0000 0000 0000 0000 0000  ................
< 000000a0: 0000 0000 0000 0000 0000 0000 0000 0000  ................
< 000000b0: 0000 0000 0000 0000 0000 0000 0000 0000  ................
< 000000c0: 0000 0000 0000 0000 0000 0000 0000 0000  ................
< 000000d0: 0000 0000 0000 0000 0000 0000 0000 0000  ................
< 000000e0: 0000 0000 0000 0000 0000 0000 0000 0000  ................
< 000000f0: 0000 0000 0000 0000 0000 0000 0000 0000  ................
---
> 00000040: 3c47 3126 c938 aa6c 7bb0 eac0 27e7 0e7d  <G1&.8.l{...'..}
> 00000050: 522b eed1 e072 276c b6f9 44d9 6361 679f  R+...r'l..D.cag.
> 00000060: 8054 e65d ab27 1c1b 4637 5f12 d868 b41d  .T.].'..F7_..h..
> 00000070: 69a8 9c77 61c5 64c3 2d2c 8e73 5edc ff93  i..wa.d.-,.s^...
> 00000080: c174 884d 1fe3 5199 d18f 3411 5009 ee12  .t.M..Q...4.P...
> 00000090: 92e4 bf73 0e8b fc0e ccd7 e5cf 96ad 663a  ...s..........f:
> 000000a0: 5372 3b6c 7398 32b7 5bea 3657 9d7e 9028  Sr;ls.2.[.6W.~.(
> 000000b0: 7803 eeec 4eb4 7d9b bcd4 75c7 cb2f 8c4c  x...N.}...u../.L
> 000000c0: d7ab 90c4 c8b0 6776 0e92 320a 55a4 e623  ......gv..2.U..#
> 000000d0: fac5 806b bdc5 3120 b351 a283 9ee9 460c  ...k..1 .Q....F.
> 000000e0: e882 9add fc10 ac59 df00 39c4 fa92 041f  .......Y..9.....
> 000000f0: 88c0 47f9 80a5 19ae 15aa 7566 2c74 6798  ..G.......uf,tg.

Build signed image

Based on the upper prepared firmware image, anyone can build the same signed image by signatures uploaded in code repository.

1. Use the build_signed_firmware.py script to generate the signed firmware image

export TAG=v2.7.4
pipenv run ./script/build_signed_firmware.py -f ./build/bithd-$TAG-prepared.bin -s ./signatures/$TAG.csv

2. shasum -a 256 ./build/bithd-$TAG-signed.bin (calculate sha256 checksum)