Web3 signer that derives address and signs transactions using AWS KMS.

$ npm i @rumblefishdev/eth-signer-kms

aws-sdk

In order to work properly AWS KMS managed key must be:

• asymmetric
• able to sign and verify
• ECC_SECG_P256K1 specified

Client using the library should have the following IAM permissions to the key that it uses:

  - Effect: Allow
    Action:
      - 'kms:Sign'
      - 'kms:GetPublicKey'
    Resource: !Ref KMSKeyArn

KMSSigner is an ethers Signer instance that uses AWS KMS stored keys to sign ethereum transactions.

keyId can be obtained via KMS package of aws-sdk or directly via AWS console. https://github.com/ethereumjs/ethereumjs-monorepo

• KmsSigner initialization

new KMSSigner(provider, keyId, kms)

• signMessage

await kmsSigner.signMessage(...)

• _signTypedData

await kmsSigner._signTypedData(...)

• getEthAddressFromKMS

await getEthAddressFromKMS(...)

KMSProvider class became KMSSigner, as its instance no longer creates provider but receives one in constructor.

That approach extracts provider dependency from the package and as a result makes it more flexible in terms of use and testing.

@lucashenning @truffle team