Nested Finance Ledger plugin

Ledger lightweight app for Nested.

Plugins:

Plugins are lightweight applications that go hand-in-hand with the Ethereum Application on Nano S, X and S+ devices.

They allow users to safely interact with smart contracts by parsing the transaction data and displaying its content in a human readable way.

It is STRONGLY recommended to follow the plugin guide in order to better understand the flow and the context for plugins.

Formating:

The C source code is expected to be formatted with clang-format 11.0.0 or higher.

Environment Setup:

Get Docker and Docker-compose.

In a terminal window:

mkdir plugin_dev

cd plugin_dev

git clone https://github.com/LedgerHQ/app-ethereum

git clone https://github.com/LedgerHQ/plugin-tools

git clone https://github.com/NestedFi/nested-ledger-plugin/

Build the apps

Launch Docker.

In the same terminal:

cd plugin-tools

./start.sh

cd ../nested-ledger-plugin/tests/

./build_locals_test.sh all

If needed, replace all with the appropriate flags to specifically build the plugin for S, X and the ethereum app.

Running the tests:

Testing with ZEMU:

The tests consist of recent snapshots in ./tests/snapshot-tmp being compared to a set of expected snapshots located in

./tests/snapshots.

Open another terminal window.

cd <path>/nested-ledger-plugin/tests.

yarn test to run all tests

OR

yarn test -t "<name-of-test>" to run a singular test.

The singular test names can be found in the ./tests/src/<test-folder>/*.test.js files.

Note: Sometimes, batched tests may fail. It is recommended to launch a singular test for the failed one to make sure the error does not come from the ZEMU tester.

Find more information about the Zondax ZEMU tester.

More information on the speculos doc page.

Plugin modifications:

Basic modifications:

The plugin has 3 basic components for modifications:

1. Number of screens.
2. Screen function calls.
3. String macros and functions.

1. Number of screens:

There are two variables that can set the screen number.

In ./src/handle_finalize.c the msg->numScreens variable defines how many screens will be displayed.

In ./src/handle_provide_token.c the msg->additionalScreens variable increases the previously set screen number.

Both are summed into msg->screenIndex which is used to scroll through screens.

2. Screen function calls:

There are two functions where the screen strings are set.

ID screen:

The first screen is the ID screen, set in ./src/handle_query_contract_id.c.

Note: It is not included in the amount of screens of msg->screenIndex.

UI screens:

These screens are set in ./src/handle_query_contract_ui.c.

Edit the switch(msg->screenIndex) cases of handle_<name-of-action>_ui() functions if needed.

3. String macros and functions:

The strings displayed by the plugin are set by macros and functions.

Macros:

• TITLE_<NAME_OF_ACTION>_SCREEN_#_UI (top)
• MSG_<NAME_OF_ACTION>_SCREEN_#_UI (bottom)

Edit these in ./src/text.h to modify the strings displayed to the user.

Functions:

These utilitary functions are used for displaying addresses, tickers, amounts, etc.

They are located in in ./src/text_utils.c.

Advanced modifications:

Follow this guide to further modify the plugin.

Deployment

Visit this page to make sure the plugin meets the standards and you have completed all the steps necessary for deployment.