deriveKey.js

export default async (publicKeyJwk, privateKeyJwk) => {
  const publicKey = await window.crypto.subtle.importKey(
    "jwk",
    publicKeyJwk,
    {
      name: "ECDH",
      namedCurve: "P-256",
    },
    true,
    []
  );

  const privateKey = await window.crypto.subtle.importKey(
    "jwk",
    privateKeyJwk,
    {
      name: "ECDH",
      namedCurve: "P-256",
    },
    true,
    ["deriveKey", "deriveBits"]
  );

  return await window.crypto.subtle.deriveKey(
    { name: "ECDH", public: publicKey },
    privateKey,
    { name: "AES-GCM", length: 256 },
    true,
    ["encrypt", "decrypt"]
  );
};