using taler crypto

4 files changed, 75 insertions, 262 deletions

diff --git a/packages/exchange-backoffice-ui/src/Dashboard.tsx b/packages/exchange-backoffice-ui/src/Dashboard.tsx
index 9f4a43513..6794ca1f8 100644
--- a/packages/exchange-backoffice-ui/src/Dashboard.tsx
+++ b/packages/exchange-backoffice-ui/src/Dashboard.tsx
@@ -1,36 +1,13 @@
-import { Dialog, Menu, Transition } from "@headlessui/react";
-import {
-  ChevronDownIcon,
-  MagnifyingGlassIcon,
-  UserIcon,
-  XCircleIcon,
-} from "@heroicons/react/20/solid";
-import {
-  Bars3Icon,
-  BellIcon,
-  CheckCircleIcon,
-  Cog6ToothIcon,
-  XMarkIcon,
-} from "@heroicons/react/24/outline";
+import { useNotifications } from "@gnu-taler/web-util/browser";
+import { Dialog, Transition } from "@headlessui/react";
+import { UserIcon, XCircleIcon } from "@heroicons/react/20/solid";
+import { CheckCircleIcon, XMarkIcon } from "@heroicons/react/24/outline";
+import { InformationCircleIcon } from "@heroicons/react/24/solid";
 import { ComponentChildren, Fragment, VNode, h } from "preact";
-import { ForwardedRef, forwardRef } from "preact/compat";
-import { useEffect, useRef, useState } from "preact/hooks";
+import { useState } from "preact/hooks";
+import logo from "./assets/logo-2021.svg";
 import { Pages } from "./pages.js";
 import { Router, useCurrentLocation } from "./route.js";
-import { InformationCircleIcon } from "@heroicons/react/24/solid";
-import {
-  useLocalStorage,
-  useMemoryStorage,
-  useNotifications,
-} from "@gnu-taler/web-util/browser";
-import {
-  AbsoluteTime,
-  Codec,
-  buildCodecForObject,
-  codecForAbsoluteTime,
-  codecForString,
-} from "@gnu-taler/taler-util";
-import logo from "./assets/logo-2021.svg";
 
 function classNames(...classes: string[]) {
   return classes.filter(Boolean).join(" ");
@@ -329,25 +306,7 @@ function NavigationBar({
   );
 }
 
-export interface Officer {
-  salt: string;
-  when: AbsoluteTime;
-  key: string;
-}
-
-export const codecForOfficer = (): Codec<Officer> =>
-  buildCodecForObject<Officer>()
-    .property("salt", codecForString()) // FIXME
-    .property("when", codecForAbsoluteTime) // FIXME
-    .property("key", codecForString())
-    .build("Officer");
-
 function TopBar({ onOpenSidebar }: { onOpenSidebar: () => void }) {
-  const password = useMemoryStorage("password");
-  const officer = useLocalStorage("officer", {
-    codec: codecForOfficer(),
-  });
-
   return (
     <div class="relative flex h-16 justify-between">
       <div class="relative z-10 flex p-2 lg:hidden">
diff --git a/packages/exchange-backoffice-ui/src/account.ts b/packages/exchange-backoffice-ui/src/account.ts
index 6c3766940..05f0f8984 100644
--- a/packages/exchange-backoffice-ui/src/account.ts
+++ b/packages/exchange-backoffice-ui/src/account.ts
@@ -2,28 +2,17 @@ import {
   bytesToString,
   createEddsaKeyPair,
   decodeCrock,
+  decryptWithDerivedKey,
+  eddsaGetPublic,
   encodeCrock,
   encryptWithDerivedKey,
   getRandomBytesF,
   stringToBytes,
 } from "@gnu-taler/taler-util";
 
-/**
- * Create a new session id from which it will
- * be derive the crypto parameters from
- * securing the private key
- *
- * @returns session id as string
- */
-export function createSalt(): string {
-  const salt = crypto.getRandomValues(new Uint8Array(8));
-  const iv = crypto.getRandomValues(new Uint8Array(12));
-  return encodeCrock(salt.buffer) + "-" + encodeCrock(iv.buffer);
-}
-
 export interface Account {
-  accountId: string;
-  secret: CryptoKey;
+  accountId: AccountId;
+  signingKey: SigningKey;
 }
 
 /**
@@ -35,25 +24,36 @@ export interface Account {
  * @returns
  */
 export async function unlockAccount(
-  salt: string,
-  key: string,
+  account: LockedAccount,
   password: string,
 ): Promise<Account> {
-  const rawKey = str2ab(window.atob(key));
+  const rawKey = decodeCrock(account);
+  const rawPassword = stringToBytes(password);
 
-  const privateKey = await recoverWithPassword(rawKey, salt, password);
+  const signingKey = (await decryptWithDerivedKey(
+    rawKey,
+    rawPassword,
+    password,
+  ).catch((e: Error) => {
+    throw new UnwrapKeyError(e.message);
+  })) as SigningKey;
 
-  const publicKey = await getPublicFromPrivate(privateKey);
+  const publicKey = eddsaGetPublic(signingKey);
 
-  const pubRaw = await crypto.subtle.exportKey("spki", publicKey).catch((e) => {
-    throw new Error(String(e));
-  });
+  const accountId = encodeCrock(publicKey) as AccountId;
 
-  const accountId = btoa(ab2str(pubRaw));
-
-  return { accountId, secret: privateKey };
+  return { accountId, signingKey };
 }
 
+declare const opaque_Account: unique symbol;
+export type LockedAccount = string & { [opaque_Account]: true };
+
+declare const opaque_AccountId: unique symbol;
+export type AccountId = string & { [opaque_AccountId]: true };
+
+declare const opaque_SigningKey: unique symbol;
+export type SigningKey = Uint8Array & { [opaque_SigningKey]: true };
+
 /**
  * Create new account (secured private key) under session
  * secured with the given password
@@ -62,9 +62,10 @@ export async function unlockAccount(
  * @param password
  * @returns
  */
-export async function createNewAccount(password: string) {
+export async function createNewAccount(
+  password: string,
+): Promise<LockedAccount> {
   const { eddsaPriv } = createEddsaKeyPair();
-  const salt = createSalt();
 
   const key = stringToBytes(password);
 
@@ -72,178 +73,18 @@ export async function createNewAccount(password: string) {
     getRandomBytesF(24),
     key,
     eddsaPriv,
-    salt,
+    password,
   );
 
-  const protectedPriv = bytesToString(protectedPrivKey);
-
-  return { accountId: protectedPriv, salt };
-}
-
-const rsaAlgorithm: RsaHashedKeyGenParams = {
-  name: "RSA-OAEP",
-  modulusLength: 2048,
-  publicExponent: new Uint8Array([0x01, 0x00, 0x01]),
-  hash: "SHA-256",
-};
-
-async function createPair(): Promise<CryptoKeyPair> {
-  const key = await crypto.subtle
-    .generateKey(rsaAlgorithm, true, ["encrypt", "decrypt"])
-    .catch((e) => {
-      throw new Error(String(e));
-    });
-  return key;
-}
-
-const textEncoder = new TextEncoder();
-
-async function protectWithPassword(
-  privateKey: CryptoKey,
-  sessionId: string,
-  password: string,
-): Promise<ArrayBuffer> {
-  const { salt, initVector: iv } = getCryptoParameters(sessionId);
-  const passwordAsKey = await crypto.subtle
-    .importKey("raw", textEncoder.encode(password), { name: "PBKDF2" }, false, [
-      "deriveBits",
-      "deriveKey",
-    ])
-    .catch((e) => {
-      throw new Error(String(e));
-    });
-  const wrappingKey = await crypto.subtle
-    .deriveKey(
-      {
-        name: "PBKDF2",
-        salt,
-        iterations: 100000,
-        hash: "SHA-256",
-      },
-      passwordAsKey,
-      { name: "AES-GCM", length: 256 },
-      true,
-      ["wrapKey", "unwrapKey"],
-    )
-    .catch((e) => {
-      throw new Error(String(e));
-    });
-
-  const protectedPrivKey = await crypto.subtle
-    .wrapKey("pkcs8", privateKey, wrappingKey, {
-      name: "AES-GCM",
-      iv,
-    })
-    .catch((e) => {
-      throw new Error(String(e));
-    });
-  return protectedPrivKey;
-}
-
-async function recoverWithPassword(
-  value: ArrayBuffer,
-  sessionId: string,
-  password: string,
-): Promise<CryptoKey> {
-  const { salt, initVector: iv } = getCryptoParameters(sessionId);
-
-  const master = await crypto.subtle
-    .importKey("raw", textEncoder.encode(password), { name: "PBKDF2" }, false, [
-      "deriveBits",
-      "deriveKey",
-    ])
-    .catch((e) => {
-      throw new UnwrapKeyError("starting", String(e));
-    });
+  const protectedPriv = encodeCrock(protectedPrivKey);
 
-  const unwrappingKey = await crypto.subtle
-    .deriveKey(
-      {
-        name: "PBKDF2",
-        salt,
-        iterations: 100000,
-        hash: "SHA-256",
-      },
-      master,
-      { name: "AES-GCM", length: 256 },
-      true,
-      ["wrapKey", "unwrapKey"],
-    )
-    .catch((e) => {
-      throw new UnwrapKeyError("deriving", String(e));
-    });
-
-  const privKey = await crypto.subtle
-    .unwrapKey(
-      "pkcs8",
-      value,
-      unwrappingKey,
-      {
-        name: "AES-GCM",
-        iv,
-      },
-      rsaAlgorithm,
-      true,
-      ["decrypt"],
-    )
-    .catch((e) => {
-      throw new UnwrapKeyError("unwrapping", String(e));
-    });
-  return privKey;
+  return protectedPriv as LockedAccount;
 }
 
-type Steps = "starting" | "deriving" | "unwrapping";
 export class UnwrapKeyError extends Error {
-  public step: Steps;
   public cause: string;
-  constructor(step: Steps, cause: string) {
-    super(`Recovering private key failed on "${step}": ${cause}`);
-    this.step = step;
+  constructor(cause: string) {
+    super(`Recovering private key failed on: ${cause}`);
     this.cause = cause;
   }
 }
-
-/**
- * Looks like there is no easy way to do it with the Web Crypto API
- */
-async function getPublicFromPrivate(key: CryptoKey): Promise<CryptoKey> {
-  const jwk = await crypto.subtle.exportKey("jwk", key).catch((e) => {
-    throw new Error(String(e));
-  });
-
-  delete jwk.d;
-  delete jwk.dp;
-  delete jwk.dq;
-  delete jwk.q;
-  delete jwk.qi;
-  jwk.key_ops = ["encrypt"];
-
-  return crypto.subtle
-    .importKey("jwk", jwk, rsaAlgorithm, true, ["encrypt"])
-    .catch((e) => {
-      throw new Error(String(e));
-    });
-}
-
-function ab2str(buf: ArrayBuffer) {
-  return String.fromCharCode.apply(null, Array.from(new Uint8Array(buf)));
-}
-function str2ab(str: string) {
-  const buf = new ArrayBuffer(str.length);
-  const bufView = new Uint8Array(buf);
-  for (let i = 0, strLen = str.length; i < strLen; i++) {
-    bufView[i] = str.charCodeAt(i);
-  }
-  return buf;
-}
-
-function getCryptoParameters(sessionId: string): {
-  salt: Uint8Array;
-  initVector: Uint8Array;
-} {
-  const [saltId, vectorId] = sessionId.split("-");
-  return {
-    salt: decodeCrock(saltId),
-    initVector: decodeCrock(vectorId),
-  };
-}
diff --git a/packages/exchange-backoffice-ui/src/pages/Officer.tsx b/packages/exchange-backoffice-ui/src/pages/Officer.tsx
index 39e368b37..40ec33018 100644
--- a/packages/exchange-backoffice-ui/src/pages/Officer.tsx
+++ b/packages/exchange-backoffice-ui/src/pages/Officer.tsx
@@ -1,4 +1,11 @@
-import { AbsoluteTime, TranslatedString } from "@gnu-taler/taler-util";
+import {
+  AbsoluteTime,
+  Codec,
+  TranslatedString,
+  buildCodecForObject,
+  codecForAbsoluteTime,
+  codecForString,
+} from "@gnu-taler/taler-util";
 import {
   notifyError,
   notifyInfo,
@@ -10,12 +17,25 @@ import { VNode, h } from "preact";
 import { useEffect, useState } from "preact/hooks";
 import {
   Account,
+  LockedAccount,
   UnwrapKeyError,
   createNewAccount,
   unlockAccount,
 } from "../account.js";
 import { createNewForm } from "../handlers/forms.js";
-import { Officer, codecForOfficer } from "../Dashboard.js";
+
+export interface Officer {
+  account: LockedAccount;
+  when: AbsoluteTime;
+}
+
+const codecForLockedAccount = codecForString() as Codec<LockedAccount>;
+
+export const codecForOfficer = (): Codec<Officer> =>
+  buildCodecForObject<Officer>()
+    .property("account", codecForLockedAccount) // FIXME
+    .property("when", codecForAbsoluteTime) // FIXME
+    .build("Officer");
 
 export function Officer() {
   const password = useMemoryStorage("password");
@@ -29,7 +49,7 @@ export function Officer() {
       return;
     }
 
-    unlockAccount(officer.value.salt, officer.value.key, password.value)
+    unlockAccount(officer.value.account, password.value)
       .then((keys) => setKeys(keys ?? { accountId: "", pub: "" }))
       .catch((e) => {
         if (e instanceof UnwrapKeyError) {
@@ -38,16 +58,12 @@ export function Officer() {
       });
   }, [officer.value, password.value]);
 
-  if (
-    officer.value === undefined ||
-    !officer.value.key ||
-    !officer.value.salt
-  ) {
+  if (officer.value === undefined || !officer.value.account) {
     return (
       <CreateAccount
-        onNewAccount={(salt, key, pwd) => {
+        onNewAccount={(account, pwd) => {
           password.update(pwd);
-          officer.update({ salt, when: AbsoluteTime.now(), key });
+          officer.update({ account, when: AbsoluteTime.now() });
         }}
       />
     );
@@ -56,8 +72,7 @@ export function Officer() {
   if (password.value === undefined) {
     return (
       <UnlockAccount
-        salt={officer.value.salt}
-        sealedKey={officer.value.key}
+        lockedAccount={officer.value.account}
         onAccountUnlocked={(pwd) => {
           password.update(pwd);
         }}
@@ -114,7 +129,7 @@ export function Officer() {
 function CreateAccount({
   onNewAccount,
 }: {
-  onNewAccount: (salt: string, accountId: string, password: string) => void;
+  onNewAccount: (account: LockedAccount, password: string) => void;
 }): VNode {
   const { i18n } = useTranslationContext();
   const Form = createNewForm<{
@@ -158,8 +173,8 @@ function CreateAccount({
               };
             }}
             onSubmit={async (v) => {
-              const keys = await createNewAccount(v.password);
-              onNewAccount(keys.salt, keys.accountId, v.password);
+              const account = await createNewAccount(v.password);
+              onNewAccount(account, v.password);
             }}
           >
             <div class="mb-4">
@@ -198,12 +213,10 @@ function CreateAccount({
 }
 
 function UnlockAccount({
-  salt,
-  sealedKey,
+  lockedAccount,
   onAccountUnlocked,
 }: {
-  salt: string;
-  sealedKey: string;
+  lockedAccount: LockedAccount;
   onAccountUnlocked: (password: string) => void;
 }): VNode {
   const Form = createNewForm<{
@@ -228,7 +241,7 @@ function UnlockAccount({
             onSubmit={async (v) => {
               try {
                 // test login
-                await unlockAccount(salt, sealedKey, v.password);
+                await unlockAccount(lockedAccount, v.password);
 
                 onAccountUnlocked(v.password ?? "");
                 notifyInfo("Account unlocked" as TranslatedString);
diff --git a/packages/taler-util/src/taler-crypto.ts b/packages/taler-util/src/taler-crypto.ts
index 6fc6d14f6..4a657b621 100644
--- a/packages/taler-util/src/taler-crypto.ts
+++ b/packages/taler-util/src/taler-crypto.ts
@@ -1406,7 +1406,7 @@ export async function encryptWithDerivedKey(
 
 const nonceSize = 24;
 
-async function decryptWithDerivedKey(
+export async function decryptWithDerivedKey(
   ciphertext: OpaqueData,
   keySeed: OpaqueData,
   salt: string,