das-eth-sig-util

A small collection of Ethereum signing functions.

You can find usage examples here

Available on NPM

Installation

yarn add das-eth-sig-util

or

npm install das-eth-sig-util

Methods

concatSig(v, r, s)

All three arguments should be provided as buffers.

Returns a continuous, hex-prefixed hex value for the signature, suitable for inclusion in a JSON transaction's data field.

normalize(address)

Takes an address of either upper or lower case, with or without a hex prefix, and returns an all-lowercase, hex-prefixed address, suitable for submitting to an ethereum provider.

personalSign (privateKeyBuffer, msgParams)

msgParams should have a data key that is hex-encoded data to sign.

Returns the prefixed signature expected for calls to eth.personalSign.

recoverPersonalSignature (msgParams)

msgParams should have a data key that is hex-encoded data unsigned, and a sig key that is hex-encoded and already signed.

Returns a hex-encoded sender address.

signTypedData (privateKeyBuffer, msgParams, version)

Sign typed data according to EIP-712. The signing differs based upon the version, which is explained in the table below.

Data should be under data key of msgParams. The method returns prefixed signature.

Version	Description
V1	This is based on an early version of EIP-712 that lacked some later security improvements, and should generally be neglected in favor of V3.
V3	Based on EIP 712, except that arrays and recursive data structures are not supported
V4	Based on EIP 712, including support for arrays and recursive data types.

recoverTypedSignature ({data, sig}, version)

Recover the address of the account used to sign the provided signature. The version parameter must match the version the signature was created with.

Expects the same data that were used for signing. sig is a prefixed signature.

typedSignatureHash (typedData)

Return hex-encoded hash of typed data params according to EIP712 schema.

extractPublicKey (msgParams)

msgParams should have a data key that is hex-encoded data unsigned, and a sig key that is hex-encoded and already signed.

Returns a hex-encoded public key.

Contributing

Setup

• Install Node.js version 12
  • If you are using nvm (recommended) running nvm use will automatically choose the right node version for you.
• Install Yarn v1
• Run yarn setup to install dependencies and run any requried post-install scripts
  • Warning: Do not use the yarn / yarn install command directly. Use yarn setup instead. The normal install command will skip required post-install scripts, leaving your development environment in an invalid state.

Testing and Linting

Run yarn test to run the tests once. To run tests on file changes, run yarn test:watch.

Run yarn lint to run the linter, or run yarn lint:fix to run the linter and fix any automatically fixable issues.

Release & Publishing

The project follows the same release process as the other libraries in the MetaMask organization. The GitHub Actions action-create-release-pr and action-publish-release are used to automate the release process; see those repositories for more information about how they work.

1. Choose a release version.

   • The release version should be chosen according to SemVer. Analyze the changes to see whether they include any breaking changes, new features, or deprecations, then choose the appropriate SemVer version. See the SemVer specification for more information.

2. If this release is backporting changes onto a previous release, then ensure there is a major version branch for that version (e.g. 1.x for a v1 backport release).

   • The major version branch should be set to the most recent release with that major version. For example, when backporting a v1.0.2 release, you'd want to ensure there was a 1.x branch that was set to the v1.0.1 tag.

3. Trigger the workflow_dispatch event manually for the Create Release Pull Request action to create the release PR.

   • For a backport release, the base branch should be the major version branch that you ensured existed in step 2. For a normal release, the base branch should be the main branch for that repository (which should be the default value).
   • This should trigger the action-create-release-pr workflow to create the release PR.

4. Update the changelog to move each change entry into the appropriate change category (See here for the full list of change categories, and the correct ordering), and edit them to be more easily understood by users of the package.

   • Generally any changes that don't affect consumers of the package (e.g. lockfile changes or development environment changes) are omitted. Exceptions may be made for changes that might be of interest despite not having an effect upon the published package (e.g. major test improvements, security improvements, improved documentation, etc.).
   • Try to explain each change in terms that users of the package would understand (e.g. avoid referencing internal variables/concepts).
   • Consolidate related changes into one change entry if it makes it easier to explain.
   • Run yarn auto-changelog validate --rc to check that the changelog is correctly formatted.

5. Review and QA the release.

   • If changes are made to the base branch, the release branch will need to be updated with these changes and review/QA will need to restart again. As such, it's probably best to avoid merging other PRs into the base branch while review is underway.

6. Squash & Merge the release.

   • This should trigger the action-publish-release workflow to tag the final release commit and publish the release on GitHub.

7. Publish the release on npm.

   • Be very careful to use a clean local environment to publish the release, and follow exactly the same steps used during CI.
   • Use npm publish --dry-run to examine the release contents to ensure the correct files are included. Compare to previous releases if necessary (e.g. using https://unpkg.com/browse/[package name]@[package version]/).
   • Once you are confident the release contents are correct, publish the release using npm publish.