Merge calcSalt into authBuilder

src/authBuilder.ts

@@ -254,6 +254,30 @@ export const calcNonce = (args: typeDataArgs) => {
     return utils.hexlify(utils.concat([nonceA, nonceB]));
 };
 
+// @Note Crypto.subtle is only available in localhost or secure contexts (HTTPS).
+function getCrypto() {
+    try {
+        return window.crypto;
+    } catch {
+        return crypto;
+    }
+}
+
+export async function calcSalt(password: string, salt = "salt", iterations = 1e7) {
+    const crypto = getCrypto();
+    const textEncoder = new TextEncoder();
+    const passwordBuffer = textEncoder.encode(password);
+    const importedKey = await crypto.subtle.importKey("raw", passwordBuffer, "PBKDF2", false, ["deriveBits"]);
+
+    const saltBuffer = textEncoder.encode(salt);
+    const params = { name: "PBKDF2", hash: "SHA-256", salt: saltBuffer, iterations };
+    const derivation = await crypto.subtle.deriveBits(params, importedKey, 256);
+
+    return Array.from(new Uint8Array(derivation))
+        .map((b) => b.toString(16).padStart(2, "0"))
+        .join("");
+}
+
 export function calcGuardianId(subHash: string, guardian: string) {
     return utils.keccak256(utils.defaultAbiCoder.encode(["bytes32", "address"], [subHash, guardian]));
 }

src/index.ts

@@ -5,7 +5,6 @@ export * from "./jwt";
 export * from "./jwtProvider";
 export * from "./jwkProvider";
 export * from "./userOp";
-export * from "./calcSalt";
 export * from "./account-utils";
 export * from "./utils";
 export * from "./circuit-helpers";