Added SRP helpers to serverside

backend/src/lib/crypto/srp.ts

@@ -1,4 +1,12 @@
+import argon2, { argon2id } from "argon2";
+import crypto from "crypto";
 import jsrp from "jsrp";
+import nacl from "tweetnacl";
+import { encodeBase64 } from "tweetnacl-util";
+
+import { TUserEncryptionKeys } from "@app/db/schemas";
+
+import { decryptSymmetric, encryptAsymmetric, encryptSymmetric } from "./encryption";
 
 export const generateSrpServerKey = async (salt: string, verifier: string) => {
   // eslint-disable-next-line new-cap
@@ -24,3 +32,97 @@ export const srpCheckClientProof = async (
   server.setClientPublicKey(clientPublicKey);
   return server.checkClientProof(clientProof);
 };
+
+// FOR GHOST USER STUFF
+export const generateUserSrpKeys = async (email: string, password: string) => {
+  const pair = nacl.box.keyPair();
+  const secretKeyUint8Array = pair.secretKey;
+  const publicKeyUint8Array = pair.publicKey;
+  const privateKey = encodeBase64(secretKeyUint8Array);
+  const publicKey = encodeBase64(publicKeyUint8Array);
+
+  // eslint-disable-next-line
+  const client = new jsrp.client();
+  await new Promise((resolve) => {
+    client.init({ username: email, password }, () => resolve(null));
+  });
+  const { salt, verifier } = await new Promise<{ salt: string; verifier: string }>((resolve, reject) => {
+    client.createVerifier((err, res) => {
+      if (err) return reject(err);
+      return resolve(res);
+    });
+  });
+  const derivedKey = await argon2.hash(password, {
+    salt: Buffer.from(salt),
+    memoryCost: 65536,
+    timeCost: 3,
+    parallelism: 1,
+    hashLength: 32,
+    type: argon2id,
+    raw: true
+  });
+  if (!derivedKey) throw new Error("Failed to derive key from password");
+
+  const key = crypto.randomBytes(32);
+
+  // create encrypted private key by encrypting the private
+  // key with the symmetric key [key]
+  const {
+    ciphertext: encryptedPrivateKey,
+    iv: encryptedPrivateKeyIV,
+    tag: encryptedPrivateKeyTag
+  } = encryptSymmetric(privateKey, key.toString("base64"));
+
+  // create the protected key by encrypting the symmetric key
+  // [key] with the derived key
+  const {
+    ciphertext: protectedKey,
+    iv: protectedKeyIV,
+    tag: protectedKeyTag
+  } = encryptSymmetric(key.toString("hex"), derivedKey.toString("base64"));
+
+  return {
+    protectedKey,
+    plainPrivateKey: privateKey,
+    protectedKeyIV,
+    protectedKeyTag,
+    publicKey,
+    encryptedPrivateKey,
+    encryptedPrivateKeyIV,
+    encryptedPrivateKeyTag,
+    salt,
+    verifier
+  };
+};
+
+export const getUserPrivateKey = async (password: string, user: TUserEncryptionKeys) => {
+  const derivedKey = await argon2.hash(password, {
+    salt: Buffer.from(user.salt),
+    memoryCost: 65536,
+    timeCost: 3,
+    parallelism: 1,
+    hashLength: 32,
+    type: argon2id,
+    raw: true
+  });
+  if (!derivedKey) throw new Error("Failed to derive key from password");
+  const key = decryptSymmetric({
+    ciphertext: user.protectedKey!,
+    iv: user.protectedKeyIV!,
+    tag: user.protectedKeyTag!,
+    key: derivedKey.toString("base64")
+  });
+  const privateKey = decryptSymmetric({
+    ciphertext: user.encryptedPrivateKey,
+    iv: user.iv,
+    tag: user.tag,
+    key
+  });
+  return privateKey;
+};
+
+export const buildUserProjectKey = async (privateKey: string, publickey: string) => {
+  const randomBytes = crypto.randomBytes(16).toString("hex");
+  const { nonce, ciphertext } = encryptAsymmetric(randomBytes, publickey, privateKey);
+  return { nonce, ciphertext };
+};