How to get a wallet address on server side

[softcheetah]

I want to know how to get a wallet address from idToken on server side.

https://web3auth.io/docs/server-side-verification/social-login-users

[himanshuchawla009]

You can derive the eth wallet address from public_key given in id token

{
  "iat": 1655835494,
  "aud": "BCtbnOamqh0cJFEUYA0NB5YkvBECZ3HLZsKfvSRBvew2EiiKW3UxpyQASSR0artjQkiUOCHeZ_ZeygXpYpxZjOs",
  "iss": "https://api.openlogin.com/",
  "email": "[email protected]",
  "name": "John Doe",
  "profileImage": "https://lh3.googleusercontent.com/a/AATXAJx3lnGmHiM4K97uLo9Rb0AxOceH-dQCBSRqGbck=s96-c",
  "verifier": "torus",
  "verifierId": "[email protected]",
  "aggregateVerifier": "tkey-google-lrc",
  "exp": 1655921894,
  "wallets": [
    {
      "public_key": "035143318b83eb5d31611f8c03582ab1200494f66f5e11a67c34f5581f48c1b70b",
      "type": "web3auth_key",
      "curve": "secp256k1"
    }
  ]
}

For ex:

const { publicToAddress } = require("ethereumjs-util")
const add = publicToAddress(Buffer.from("035143318b83eb5d31611f8c03582ab1200494f66f5e11a67c34f5581f48c1b70b", "hex"), true)
console.log("add", `0x${add.toString("hex")}`)

[softcheetah]

@himanshuchawla009 ^

[softcheetah]

I tried https://github.com/cryptocoinjs/secp256k1-node, and publicKeyToAddress worked.
But it gives me the wrong address

[himanshuchawla009]

@softcheetah , i have edited my answer with a better code snippet. I checked that updated code snippet it is working and returning correct address.

[softcheetah]

Thanks

[evqlab]

wallets: [

    {
      public_key: '02386ab238ea8db438d6b10f6ddbb8801725114298d6f374a4c47072d6e71bf8ab',
      type: 'web3auth_app_key',
      curve: 'secp256k1'
    }
  ],

The Code I used in express js -

function publicKeyToAddress(publicKey) {
  const add = publicToAddress(Buffer.from(publicKey, "hex"), true)
  console.log("add", `0x${add.toString("hex")}`)
}

The Client Side address -
0x9E831D6f587C911043668fF9b0648fc38547Db01
The address I received in the backend -
0xc43069d04089745ec14944b1cd249a9c763df8da

Why am I getting an incorrect address?

@himanshuchawla009 himanshuchawla009

[qmn1711]

hi @himanshuchawla009, How can I derive a wallet address from ed25519 public key?

[softcheetah]

Please try this.

import EthCrypto from "eth-crypto";

const walletAddress = EthCrypto.publicKey.toAddress(public_key);

[qmn1711]

@softcheetah The ed25519 type I mean is Solana account address type.EthCrypto.publicKey.toAddress(public_key); threw error. I tried with new PublicKey(public_key) from @solana/web3.js, it threw Non-base58 character. How can I derive solana account address from public_key?

Example data on server side:

// Server side verification
const jwtDecoded = await jose.jwtVerify(idToken, jwks, {
  algorithms: ['ES256'],
});

// Data of jwtDecoded.payload.wallets[0]
//
// wallet {
//   public_key: 'ccd5a0d9c6ff7d379f58b694a16193e3b89b7c8556fcaf34523ce3cc5e2b3a36',
//   type: 'web3auth_app_key',
//   curve: 'ed25519'
// }

[ajobi-uhc]

For anyone who is trying to get a solana wallet address using the returned public key please import the bs58 library and run

const pubkeyBase58 = bs58.encode(Buffer.from(, 'hex'));
const solanaWalletAddress = new Publickey(pubkeyBase58)