[TASK] Provide Ledger HW-Wallet Support

[ghost]

Continuation of #3427 and #3631
Note: this issue has an edit-history

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Prerequisites

Should be done before providing Ledger (or any other hw-wallet) Support :

See: https://github.com/lazaridiscom/mm-vault

#4201 - provide metadata
#4202 - provide (metadata-based) generic ui

Solution Paths

one(!) of the following (prioritized, most favorable first) :

mm-ledger-gateway

• [TASK] Implement mm-ledger-gateway #4593 - Implement mm-ledger-gateway
  • Implemented via Add Ledger hardware wallet support #5050

Directly in Chrome

• [TASK] Enable USB for Extensions in Chrome #4205 - Enable USB for Extensions in Chrome
  • WebUSB (favored by chome devs) or U2F
  • possible solution: place a high bounty (10 ETH) to boost

hw-transport-cem

#4469 - Implement Ledger hw-transport-cem

ledger-live-desktop

https://github.com/LedgerHQ/ledger-live-desktop
(as suggested here: #4204 (comment))

Not the most elegant way, but still, a decent path (if other paths fail)

• https://developer.chrome.com/extensions/nativeMessaging#native-messaging-host
• MetaMask communicates similar to CEM.
• This should be implemented by the Ledger Team
  • Alternative: a friendly-fork could do it, too, like ledger-live-desktop-mm

mm-ledger-connect

Implementation similar to Trezor-Connect:

• Initial trezor support #4625 (Trezor)
• https://github.com/brunobar79/eth-trezor-keyring/blob/master/trezor-connect.js

(verify GPL / MIT license compliance, possibly the whole module must go from MIT to GPL)

ledger-wallet-api

https://github.com/LedgerHQ/ledger-wallet-api

Avoid (legacy), despite this seems the fastest way to achieve a result.

Use this api to interface to the Ledger Eth Chrome App.

• verify that this interfacing works from within extensions (use the bitcoin App / Interface)
• complete the development of the eth api (within the develop branch)
  • https://github.com/LedgerHQ/ledger-wallet-api/blob/develop/doc-api-ETH.md
    • IMPORTANT: only the develop branch contains ETH code
• use it to create the relevant mm-ledger-module
• Final Step: Shrink the Ledger Eth Chrome App down to a minimum code (just a gateway)

More Possible Solutions

from #4204 (comment)

(provided here mostly for the sake of completeness)

• MetaMask adds a native component, that can talk directly to USB.
• MetaMask becomes an Electron app, so can use @ledgerhq/hw-transport-node-hid.
• MetaMask only adds Ledger support to Mascara, which is purely HTTPS.

Issues with Ledger

• https://cryptoncy.net/qa/18-unable-to-install-or-uninstall-any-applications-on-ledger-nano-s.html

Deadline

30th June 2018

[jamespic]

It looks like the Chromium devs would be more open to making WebUSB available to extensions than U2F. Looking at the discussion on https://bugs.chromium.org/p/chromium/issues/detail?id=770896, the issue for adding WebUSB support, it looks like they'd like to add it, but there's some dev work to do.

I imagine they'd be more open to a pull request implementing it, that they would be for U2F.

[ghost]

This sounds good! I've updated #4205 and moved it here in the list to the top

[ghost]

#5050 has implemented ledger-support via solution-path #4593 (mm-ledger-gateway)