Session creation

High level flow of DuoSession

• Configure/Implement transport layer DuoNetworkClient
• Configure/Implement storage layer StorageClient
• Configure/Implement MessageSigner
• Create DuoSession
• Perform MPC actions

DuoSession is the main object which will be used to perform all of the MPC operations supported. To create DuoSession please follow the steps below.

Step 1 : Add library to your Project

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• Create new xcode project if you haven't.

• Add SilentShard-Duo SDK using the instructions from the Installation Guide

Step 2 : Create new session

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• Import module - duo.
• We can Create DuoSession by calling SilentShard.ECDSA.duoInitiator() or SilentShard.EdDSA.duoInitiator() (whichever applies) by providing the following parameters

1. Provide websocket client by using any of the below options :
   • Providing WebsocketConfig object to let SDK use default NetworkClient i.e. DuoNetworkClient.
   • Providing custom NetworkClient overriding(extending) DuoNetworkClient to override existing connect, read or write, etc. methods to add your own logic/configuration or additional process.
2. Provide cloud/server public key.
3. Provide storage client. (You need to implement the protocol StorageClient).
4. Provide message signer. (You need to implement the protocol MessageSigner).

Example

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ECDSA

Example.swift

import SwiftUI
import duo

struct ContentView: View {

    var body: some View {
        VStack {

            // The demo server, over TLS.
            let CLOUD_NODE_URI = "demo-server.silencelaboratories.com"

            // Other party verifying-key/public-key. Replace with your own Verifying Key.
            let cloudVerifyingKey = "cfa1ff5424d14eb60614d7ddf65a32243d26ddf7000d10007853d7336395efe4"

            // Create websocketConfig to let SilentShard use the default WebsocketClient.
            let websocketConfig = WebsocketConfig(url: CLOUD_NODE_URI, port: 443, isSecure: true)

            // Create a storageClient to persist keyshares. The SDK owns keyshare
            // storage and addresses every share by its keyId.
            let storageClient = CustomStorageClient()

            // Create a messageSigner to authenticate protocol messages. For quick-start
            // we use the test signer; do not use TestECDSAMessageSigner in production.
            // Provide your own MessageSigner backed by the Secure Enclave instead:
            // let messageSigner = CustomMessageSigner()

            // Create a DuoSession
            let duoSession = SilentShard.ECDSA.duoInitiator(
                // Do not use TestECDSAMessageSigner in production
                messageSigner: TestECDSAMessageSigner(),
                cloudVerifyingKey: cloudVerifyingKey,
                websocketConfig: websocketConfig,
                storageClient: storageClient
            )

            // or using a custom network client
            // let duoSession = SilentShard.ECDSA.duoInitiator(
            //     messageSigner: TestECDSAMessageSigner(),
            //     cloudVerifyingKey: cloudVerifyingKey,
            //     networkClient: CustomNetworkClient(),
            //     storageClient: storageClient
            // )
        }
        .padding()
    }
}

#Preview {
    ContentView()
}

EdDSA

Example.swift

import SwiftUI
import duo

struct ContentView: View {

    var body: some View {
        VStack {

            // The demo server, over TLS.
            let CLOUD_NODE_URI = "demo-server.silencelaboratories.com"

            // Other party verifying-key/public-key. Replace with your own Verifying Key.
            let cloudVerifyingKey = "cfa1ff5424d14eb60614d7ddf65a32243d26ddf7000d10007853d7336395efe4"

            // Create websocketConfig to let SilentShard use the default WebsocketClient.
            let websocketConfig = WebsocketConfig(url: CLOUD_NODE_URI, port: 443, isSecure: true)

            // Create a storageClient to persist keyshares. The SDK owns keyshare
            // storage and addresses every share by its keyId.
            let storageClient = CustomStorageClient()

            // Create a messageSigner to authenticate protocol messages. For quick-start
            // we use the test signer; do not use TestEdDSAMessageSigner in production.
            // Provide your own MessageSigner backed by the Secure Enclave instead:
            // let messageSigner = CustomMessageSigner()

            // Create a DuoSession
            let duoSession = SilentShard.EdDSA.duoInitiator(
                // Do not use TestEdDSAMessageSigner in production
                messageSigner: TestEdDSAMessageSigner(),
                cloudVerifyingKey: cloudVerifyingKey,
                websocketConfig: websocketConfig,
                storageClient: storageClient
            )

            // or using a custom network client
            // let duoSession = SilentShard.EdDSA.duoInitiator(
            //     messageSigner: TestEdDSAMessageSigner(),
            //     cloudVerifyingKey: cloudVerifyingKey,
            //     networkClient: CustomNetworkClient(),
            //     storageClient: storageClient
            // )
        }
        .padding()
    }
}

#Preview {
    ContentView()
}

• CLOUD_NODE_URI is the URI of the cloud node.
• cloudPublicKey is the cloud verifying key (Ed25519 public key).
  • This public key is used to verify the server's signature on each message
  • See example here
• SilentShard Provides API for creating MPC DuoSession (Two-Party) using ECDSA algorithm.
• ECDSA Provides factory methods for creating MPC session using ECDSA algorithm.
• DuoSession Represents a two-party computation session that lets you perform MPC operations using SilentShard protocol.

You have now successfully set up the session and are ready to start performing MPC actions! 🎉