Doesn't build and install using instructions in Ledger SDK Documentation

[brandoncurtis]

To summarize, there are two issues here:

1. Makefile ignores BOLOS_ENV and BOLOS_SDK
2. ledgerblue Python modules has issues when icons are passed in

I could not get anything in this repo to build and install using the instructions in the Ledger SDK Documentation.

As warned in the docs, this Makefile does not acknowledge BOLOS_ENV and BOLOS_SDK... instead, you have to specify GCCPATH and CLANGPATH manually.

If I run COIN=bitcoin_testnet make, I get a couple of these errors:

find: ‘/home/brandon/repos/dev-ledger-sdk/qrcode’: No such file or directory

but these appear to be harmless and it does appear to compile.

Now if I run COIN=bitcoin_testnet make load, it errors out due to a TypeError:

TARGET_NAME=TARGET_NANOS TARGET_ID=0x31100002
find: ‘/home/brandon/repos/dev-ledger-sdk/qrcode’: No such file or directory
find: ‘/home/brandon/repos/dev-ledger-sdk/qrcode’: No such file or directory
python -m ledgerblue.loadApp --appFlags 0x50 --curve secp256k1 --targetId 0x31100002 --fileName bin/app.hex --appName "Bitcoin Test" `ICONHEX=\`python /home/brandon/repos/dev-ledger-sdk/icon.py nanos_app_bitcoin_testnet.gif hexbitmaponly 2>/dev/null\` ; [ ! -z "$ICONHEX" ] && echo "--icon $ICONHEX"`   --path ""
Generated random root public key : 04a51c...
Using test master key 04a51c...
Using ephemeral key 049f372...
Broken certificate chain - loading from user key
Traceback (most recent call last):
  File "/usr/lib/python2.7/runpy.py", line 174, in _run_module_as_main
    "__main__", fname, loader, pkg_name)
  File "/usr/lib/python2.7/runpy.py", line 72, in _run_code
    exec code in run_globals
  File "/home/brandon/.virtualenvs/dev-ledger-btc-DoSE2Zou/lib/python2.7/site-packages/ledgerblue/loadApp.py", line 174, in <module>
    loader.createApp(args.appFlags, appLength, args.appName, icon, path, None, None, args.appVersion)
  File "/home/brandon/.virtualenvs/dev-ledger-btc-DoSE2Zou/local/lib/python2.7/site-packages/ledgerblue/hexLoader.py", line 163, in createApp
    data = self.encryptAES(data)
  File "/home/brandon/.virtualenvs/dev-ledger-btc-DoSE2Zou/local/lib/python2.7/site-packages/ledgerblue/hexLoader.py", line 95, in encryptAES
    encryptedData = cipher.encrypt(paddedData)
  File "/home/brandon/.virtualenvs/dev-ledger-btc-DoSE2Zou/local/lib/python2.7/site-packages/Crypto/Cipher/blockalgo.py", line 244, in encrypt
    return self._cipher.encrypt(plaintext)
TypeError: argument must be string or read-only buffer, not bytearray
Makefile:189: recipe for target 'load' failed
make: *** [load] Error 1

Now, if I try again but I pull out the Python one-liner that the Makefile runs, minus the icon part, this loads the app onto the Ledger just fine:

$ python -m ledgerblue.loadApp --appFlags 0x50 --curve secp256k1 --targetId 0x31100002 --fileName bin/app.hex --appName "Bitcoin Test"

This suggests that the problem is in here somewhere, but this also returns properly:

$ python /home/brandon/repos/dev-ledger-sdk/icon.py nanos_app_bitcoin_testnet.gif hexbitmaponly
0100000000ffffff00ffffffffffffbffe0ffc9ff99ff91ff89ff19ff39ff10ff8bffeffffffffffff

This fails:

$ python -m ledgerblue.loadApp --appFlags 0x50 --curve secp256k1 --targetId 0x31100002 --fileName bin/app.hex --appName "Bitcoin Test" --icon "0100000000ffffff00ffffffffffffbffe0ffc9ff99ff91ff89ff19ff39ff10ff8bffeffffffffffff" --path ""

So it's definitely something about how loader.createApp handles that icon hex.

If I screw up the icon hex on purpose by adding a 0x prefix:

$ python -m ledgerblue.loadApp --appFlags 0x50 --curve secp256k1 --targetId 0x31100002 --fileName bin/app.hex --appName "Bitcoin Test" --icon "0x0100000000ffffff00ffffffffffffbffe0ffc9ff99ff91ff89ff19ff39ff10ff8bffeffffffffffff" --path ""
Generated random root public key : 04d4d313382cce448d43e54e085a9732b6935134f6fbc1a5b7c240d2e6cf2bbf473b46f47fbcf0735a94490aa34d680301508156f1bfd62e9d67f2d28443aba450
Traceback (most recent call last):
  File "/usr/lib/python2.7/runpy.py", line 174, in _run_module_as_main
    "__main__", fname, loader, pkg_name)
  File "/usr/lib/python2.7/runpy.py", line 72, in _run_code
    exec code in run_globals
  File "/home/brandon/.virtualenvs/dev-ledger-btc-DoSE2Zou/lib/python2.7/site-packages/ledgerblue/loadApp.py", line 134, in <module>
    icon = bytearray.fromhex(args.icon)
ValueError: non-hexadecimal number found in fromhex() arg at position 0

Now that's interesting, because above it says argument must be string or read-only buffer, not bytearray.

In loader.createApp, the loader part is an instead of HexLoader that comes in via from .hexLoader import HexLoader.

Taking a peek inside ledgerblue/hexLoader.py:

data = b'\x0B' + struct.pack('>I', applength) + struct.pack('>I', appflags) + struct.pack('>B', len(appname)) + appname
...
data = self.encryptAES(data)
...
encryptedData = cipher.encrypt(paddedData)

Ah! Changed it to encryptedData = cipher.encrypt(buffer(paddedData)) and now make load works great.

So, it would appear this is actually a problem in the ledgerblue Python module.