ledgerhq / btchip-js-api

Ledger HW.1 JavaScript APIs

btchip-js-api

BTChip JavaScript APIs

Only available for Chrome / Chromium browsers with the following extensions installed :

• Plug-up Bridge https://chrome.google.com/webstore/detail/plug-up-bridge/mgbemnbocfpecccpecgommbeilnainej
• Plug-up Content Script https://chrome.google.com/webstore/detail/plug-up-bridge-content-sc/icnekhdkfglaecpcdkjoahlnjllocjgo

Using :

• PlugupExtension from https://github.com/ubinity/PlugupExtension
• Q from https://github.com/kriskowal/q
• async.js from https://github.com/caolan/async
• inheritance from https://code.google.com/p/inheritance/

btchip-js-api's Issues

Serialization of variable length datastructure

I'm not sure to post this issue here or on https://github.com/LedgerHQ/btchip-doc, but you don't document how you are encoding "variable length" structures.

I see from the code, that you seems to prepend the length of the data, which make sense, but have the disadvantage to crash if such data is more than 255 bytes long...

return this.card.sendApdu_async(0xe0, 0x46, outputType, p2, data, [0x9000]).then(function (outData) {
489 var result = {};
490 var scriptDataLength = outData.byteAt(0);
491 result['scriptData'] = outData.bytes(1, scriptDataLength);
492 result['authorizationRequired'] = (outData.byteAt(1 + scriptDataLength) == 0x01);
493 return result;
494 });

I'm not sure yes if that is a problem, but should I consider that every "var" data structure in https://ledgerhq.github.io/btchip-doc/bitcoin-technical.html
should be formatted as such, unless specified otherwise ? (data prepent by 1 byte length ?)