EtherealCereal

A private key, public key and address generator for the Ethereum cryptocurrency.

source

Usage

You can create a new instance of EtherealCereal, this will let you generate a new private key, public key and address from scratch.

let etherealCereal = EtherealCereal()
print(etherealCereal.privateKey)
print(etherealCereal.publicKey)
print(etherealCereal.address)

You can easily sign messages:

etherealCereal.sign(message: "I'm signing this message now.")

🎉 And that’s it! 🎉

Dependencies

Integration

EtherealCereal doesn’t depend on anything to be integrated on your app. Just use Carthage or build the framework yourself and integrate manually. Should be simple enough.

You can instantiate a new EtherealCereal object, and create a new private key from scratch, it will also allow you to derive the public key and Ethereum address from it. You can also instantiate it with a private key string directly, if a user already exists. It will derive the address and public key from that private key.

Development

Development is a bit more complicated. It currently depends on secp256k1 for the key and address generation, and signing messages. Check how to build them for iOS below.

For the Keccak-256, we embed this version here.

How to update libsecp256k1 for iOS/Simulator

If it ever comes that we need to update this repo, here are the steps to do that:

You'll need iOS-autotools, this will simplify configuring and compiling for each of the target architectures and then combining it all into a single fat binary framework.

Inside the secp256k1 folder, run the following:

ARCHS="armv7 armv7s arm64 x86_64 i386" autoframework Ether libsecp256k1.a --enable-module-recovery

Breaking it down:

ARCHS="armv7 armv7s arm64 x86_64"

This specifies the target architectures. If you’re not planning on supporting all of them, you can remove it. If Apple adds new CPU architectures, you can add it.

autoframework Ether libsecp256k1.a

autoframework is called with two arguments. The target Framework name (here I picked Ether, but it’s up to you, really), and it needs to be pointed to the generated library (this will be always libsecp256k1.a for this case).

Every subsequent argument is passed through to the ./configure call.

--enable-module-recovery

Since Ethereum requires the recoverable signature form, we need to include the recovery module for secp256k1.

After a while, you’ll have the Ether.framework bundle inside a a Frameworks folder. Just move that to a project to use it. If you’re updating it for EtherealCereal, just replace it.