Session creation

High level flow of DuoSession

• Configure/Implement transport layer DuoNetworkClient
• Configure/Implement storage layer BaseStorageClient
• 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 - duoinitiator.
• We can Create DuoSession by calling SilentShard.ECDSA.createDuoSession() or SilentShard.EdDSA.createDuoSession() (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 BaseStorageClient).
4. Provide message signer. (You need to implement the protocol MessageSigner).

Example

---

ECDSA

Example.swift

import SwiftUI
import duoinitiator

struct ContentView: View {

    var body: some View {
        VStack {
            
            let CLOUD_NODE_URI = "wss://demo-server.silencelaboratories.com"
            
            //Other party verifying-key/public-key
            let cloudVerifyingKey = "01829099948d222f9731323900bc42bd3cc6f4e692f920705a9959b3e52378f188"
            
            //Create websocketConfig to let SilentShard use default WebsocketClient.
            let websocketConfig = WebsocketConfig(
                url: CLOUD_NODE_URI,
            )
            
            //Create storage client instance to manage keyshare state
            let storageClient = CustomStorageClient()
            
            
            //Create messageSigner instance to sign message. For simplicity we are using 
            //test message signer; Do not use TestMessageSinger in production.
            //Instead create instance of your own implementation of MessageSigner. 
            //Just like below.
            //let messageSigner = CustomMessageSigner()
            
            //Create duoSession

            /*
            We only have to pass websocketConfig which contains the server config and
            communication will be handled by internal websocketClient*/
            let duoSession = SilentShard.ECDSA.createDuoSession(
                //Do not use TestMessageSinger in production
                messageSigner: TestECDSAMessageSigner(),
                cloudVerifyingKey: String(
                    cloudVerifyingKey
                ),
                websocketConfig: websocketConfig,
                storageClient: storageClient)
                
            //or using custom network client
            let duoSession = SilentShard.ECDSA.createDuoSession(
            //Do not use TestMessageSinger in production
            messageSigner: TestECDSAMessageSigner(),
            cloudVerifyingKey: String(
                cloudVerifyingKey
            ),
            networkClient: CustomNetworkClient(),
            storageClient: storageClient)
            
        }
        .padding()
    }
}

#Preview {
    ContentView()
}

EdDSA

Example.swift

import SwiftUI
import duoinitiator

struct ContentView: View {

    var body: some View {
        VStack {
            
            let CLOUD_NODE_URI = "wss://demo-server.silencelaboratories.com"
            
            //Other party verifying-key/public-key
            let cloudVerifyingKey = "01829099948d222f9731323900bc42bd3cc6f4e692f920705a9959b3e52378f188"
            
            //Create websocketConfig to let SilentShard use default WebsocketClient.
            let websocketConfig = WebsocketConfig(
                url: CLOUD_NODE_URI,
            )
            
            //Create storage client instance to manage keyshare state
            let storageClient = CustomStorageClient()
            
            
            //Create messageSigner instance to sign message. For simplicity we are using 
            //test message signer; Do not use TestMessageSinger in production.
            //Instead create instance of your own implementation of MessageSigner. 
            //Just like below.
            //let messageSigner = CustomMessageSigner()
            
            //Create duoSession

            /*
            We only have to pass websocketConfig which contains the server config and
            communication will be handled by internal websocketClient*/
            let duoSession = SilentShard.EdDSA.createDuoSession(
                //Do not use TestMessageSinger in production
                messageSigner: TestEdDSAMessageSigner(),
                cloudVerifyingKey: String(
                    cloudVerifyingKey
                ),
                websocketConfig: websocketConfig,
                storageClient: storageClient)
                
            //or using custom network client
            let duoSession = SilentShard.EdDSA.createDuoSession(
            //Do not use TestMessageSinger in production
            messageSigner: TestEdDSAMessageSigner(),
            cloudVerifyingKey: String(
                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! 🎉