Towards withdrawal in the WebExtension.

extension/background/emscriptif.js

@@ -18,23 +18,6 @@
 "use strict";
 
 
-/* The following definition is needed to make emscripted library to remain
-  'alive' after its loading. Otherwise, the normal behaviour would be:
-  loading -> look for a 'main()' -> if one is found execute it then exit,
-  otherwise just exit. See https://kripken.github.io/emscripten-site/docs/getting_started/FAQ.html
-  DO NOTE: this definition MUST precede the importing/loading of the emscripted
-  library */
-
-/* FIXME
-getLastWindow().Module = {
-
-  onRuntimeInitialized: function() {
-
-  }
-
-};
-*/
-
 /* According to emscripten's design, we need our emscripted library to be executed
   with a 'window' object as its global scope.
   Note: that holds on emscripten's functions too, that is they need to be *explicitly*
@@ -64,6 +47,8 @@ getLastWindow().Module = {
     respective functions come from (the emscripted version of) TALER_* realm. */
 
 
+const PTR_SIZE = 4;
+
 // shortcut to emscr's 'malloc'
 function emscMalloc(size) {
   var ptr = Module._malloc(size);
@@ -299,8 +284,13 @@ var GCALLrsaPrivateKeyCreate = getEmsc('GNUNET_CRYPTO_rsa_private_key_create',
 				      ['number']);
 
 var GCALLrsaBlindingKeyCreate = getEmsc('GNUNET_CRYPTO_rsa_blinding_key_create',
+                                       'number',
+				      ['number']);
+
+
+var GCALLrsaBlindingKeyEncode = getEmsc('GNUNET_CRYPTO_rsa_blinding_key_encode',
                                         'number',
-				       ['number']);
+				       ['number', 'number']);
 
 var GCrsaBlindingKeyFree = getEmsc('GNUNET_CRYPTO_rsa_blinding_key_free',
                                    'void',
@@ -514,7 +504,6 @@ let d2s = getEmsc('GNUNET_STRINGS_data_to_string_alloc',
 let sizeof_EddsaPrivateKey = 32;
 let sizeof_EddsaPublicKey = 32;
 
-
 function createEddsaKeyPair() {
   let privPtr = GCALLeddsaKeyCreate();
   let pubPtr = emscMalloc(sizeof_EddsaPublicKey);
@@ -523,3 +512,12 @@ function createEddsaKeyPair() {
   let pubStr = d2s(pubPtr, sizeof_EddsaPublicKey);
   return {priv: privStr, pub: pubStr};
 }
+
+function createRsaBlindingKey() {
+  let blindFac = GCALLrsaBlindingKeyCreate(1024);
+  let bufPtr = emscMalloc(PTR_SIZE);
+  let size = GCALLrsaBlindingKeyEncode (blindFac, bufPtr);
+  let key = d2s(Module.getValue(bufPtr, '*'), size);
+  emscFree(bufPtr);
+  return key;
+}

extension/background/libwrapper.js

@@ -1 +0,0 @@
-../../../wallet_button/firefox_src/content/lib/libWrapper.jsm

extension/background/wallet.js

@@ -1,47 +1,58 @@
 'use strict';
 
-const DONE = 4;
 const DB_NAME = "taler";
 const DB_VERSION = 1;
 
-// Shown in the UI.
-let backendFailed = false;
 
 /**
- * Run a function with the opened taler DB.
+ * Return a promise that resolves
+ * to the taler wallet db.
  */
-function withTalerDb(f) {
-  let req = indexedDB.open(DB_NAME, DB_VERSION);
-  req.addEventListener("error", (e) => {
-    // XXX: more details
-    backendFailed = true;
-  });
-  req.addEventListener("success", (e) => {
-    var db = e.target.result;
-    f(db);
-  });
-  req.addEventListener("upgradeneeded", (e) => {
-    console.log ("DB: upgrade needed: oldVersion = "+ event.oldVersion);
-    db = event.target.result;
-    switch (event.oldVersion) {
-      case 0: // DB does not exist yet
-        db.createObjectStore("mints", { keyPath: "mint_pub" });
-        db.createObjectStore("reserves", { keyPath: "reserve_pub"});
-        db.createObjectStore("denoms", { keyPath: "denom_pub" });
-        db.createObjectStore("coins", { keyPath: "coin_pub" });
-        db.createObjectStore("withdrawals", { keyPath: "id", autoIncrement: true });
-        db.createObjectStore("transactions", { keyPath: "id", autoIncrement: true });
-        break;
-    }
+function openTalerDb(cont) {
+  return new Promise((resolve, reject) => {
+    let req = indexedDB.open(DB_NAME, DB_VERSION);
+    req.addEventListener("error", (e) => {
+      reject(e);
+    });
+    req.addEventListener("success", (e) => {
+      resolve(e.target.result);
+    });
+    req.addEventListener("upgradeneeded", (e) => {
+      let db = e.target.result;
+      console.log ("DB: upgrade needed: oldVersion = " + event.oldVersion);
+      db = event.target.result;
+      switch (event.oldVersion) {
+        case 0: // DB does not exist yet
+          db.createObjectStore("mints", { keyPath: "baseUrl" });
+          db.createObjectStore("reserves", { keyPath: "reserve_pub"});
+          db.createObjectStore("denoms", { keyPath: "denom_pub" });
+          db.createObjectStore("coins", { keyPath: "coin_pub" });
+          db.createObjectStore("withdrawals", { keyPath: "id", autoIncrement: true });
+          db.createObjectStore("transactions", { keyPath: "id", autoIncrement: true });
+          break;
+      }
+    });
   });
 }
 
 
+function canonicalizeBaseUrl(url) {
+  let x = new URI(url);
+  if (!x.protocol()) {
+    x.protocol("https");
+  }
+  x.path(x.path() + "/").normalizePath();
+  x.fragment();
+  x.query();
+  return x.href()
+}
+
+
 function confirmReserve(db, detail, sendResponse) {
   console.log('detail: ' + JSON.stringify(detail));
   let keypair = createEddsaKeyPair();
   let form = new FormData();
-  let now = new Date();
+  let now = (new Date()).toString();
   form.append(detail.field_amount, detail.amount_str);
   form.append(detail.field_reserve_pub, keypair.pub);
   form.append(detail.field_mint, detail.mint);
@@ -50,15 +61,16 @@ function confirmReserve(db, detail, sendResponse) {
   console.log("making request to " + detail.post_url);
   myRequest.open('post', detail.post_url);
   myRequest.send(form);
+  let mintBaseUrl = canonicalizeBaseUrl(detail.mint);
   myRequest.addEventListener('readystatechange', (e) => {
-    if (myRequest.readyState == DONE) {
+    if (myRequest.readyState == XMLHttpRequest.DONE) {
       let resp = {};
       resp.status = myRequest.status;
       resp.text = myRequest.responseText;
       let reserveRecord = {
         reserve_pub: keypair.pub,
         reserve_priv: keypair.priv,
-        mint_base_url: detail.mint,
+        mint_base_url: mintBaseUrl,
         created: now,
         last_query: null,
         current_amount: null,
@@ -77,8 +89,10 @@ function confirmReserve(db, detail, sendResponse) {
           tx.addEventListener('complete', (e) => {
             console.log('tx complete, pk was ' + reserveRecord.reserve_pub);
             sendResponse(resp);
-            updateReserveMints(db);
-            // We have to update the mints now ...
+            var mint;
+            updateMintFromUrl(db, reserveRecord.mint_base_url)
+                .then((m) => { mint = m; return updateReserve(db, keypair.pub, mint); })
+                .then((reserve) => depleteReserve(db, reserve, mint));
           });
           break;
         default:
@@ -92,13 +106,179 @@ function confirmReserve(db, detail, sendResponse) {
 }
 
 
-/**
- * Fetch information for mints that
- * are referenced in a reserve and that were not
- * updated recently.
- */
-function updateReserveMints(db) {
+function sumAmounts() {
+  let v = 0;
+  let f = 0;
+  let c;
+  let xs = arguments;
+  if (xs.length == 0) {
+    throw "no arguments given";
+  }
+  for (let x of xs) {
+    v = (v + x.value) + Math.floor((f + x.value) / 10e6);
+    f = (f + x.fraction) % 10e6;
+    c = x.currency;
+  }
+  return {value: v, fraction:f, currency: c};
+}
 
+function subtractAmount(a1, a2) {
+  if (compareAmount(a1, a2) < 0) {
+    throw "negative result";
+  }
+  let r = {
+    currency: a1.currency,
+    value: a1.value,
+    fraction: a1.fraction
+  };
+  if (a2.fraction > a1.fraction) {
+    r.value--;
+    r.fraction += 1000000;
+  }
+  r.value -= a2.value;
+  r.fraction -= a2.fraction;
+  return r;
+}
+
+
+function compareAmount(a1, a2) {
+  if (a1.currency !== a2.currency) {
+    throw "can't compare different currencies";
+  }
+  let v1 = [a1.value + Math.floor(a1.fraction / 10e6), a1.fraction % 10e6];
+  let v2 = [a2.value + Math.floor(a2.fraction / 10e6), a2.fraction % 10e6];
+  for (let i in v1) {
+    if (v1[i] < v2[i]) {
+      return -1;
+    }
+    if (v1[i] > v2[i]) {
+      return 1;
+    }
+  }
+  return 0;
+}
+
+function copy(o) {
+  return JSON.parse(JSON.stringify(o));
+}
+
+
+function rankDenom(o1, o2) {
+  return (-1) * compareAmount(o1.value, o2.value);
+}
+
+
+function withdraw(denom, reserve, mint) {
+  let wd = {};
+  wd.denom_pub = denom.denom_pub;
+  wd.reserve_pub = reserve.reserve_pub;
+  let coin_key = createEddsaKeyPair();
+  // create RSA blinding key
+  // blind coin
+  // generate signature
+}
+
+
+/**
+ * Withdraw coins from a reserve until it is empty.
+ */
+function depleteReserve(db, reserve, mint) {
+  let denoms = copy(mint.keys.denoms);
+  let remaining = copy(reserve.current_amount);
+  denoms.sort(rankDenom);
+  for (let i = 0; i < 1000; i++) {
+    let found = false;
+    for (let d of denoms) {
+      let cost = sumAmounts(d.value, d.fee_withdraw);
+      if (compareAmount (remaining, cost) < 0) {
+        continue;
+      }
+      found = true;
+      remaining = subtractAmount(remaining, cost);
+      withdraw(d, reserve, mint);
+    }
+    if (!found) {
+      break;
+    }
+  }
+
+}
+
+
+function updateReserve(db, reservePub, mint) {
+  let reserve;
+  return new Promise((resolve, reject) => {
+    let tx = db.transaction(['reserves']);
+    tx.objectStore('reserves').get(reservePub).onsuccess = (e) => {
+      let reserve = e.target.result;
+      let reqUrl = URI("reserve/status").absoluteTo(mint.baseUrl);
+      reqUrl.query({'reserve_pub': reservePub});
+      let myRequest = new XMLHttpRequest();
+      console.log("making request to " + reqUrl.href());
+      myRequest.open('get', reqUrl.href());
+      myRequest.send();
+      myRequest.addEventListener('readystatechange', (e) => {
+        if (myRequest.readyState == XMLHttpRequest.DONE) {
+          if (myRequest.status != 200) {
+            reject();
+            return;
+          }
+          let reserveInfo = JSON.parse(myRequest.responseText);
+          console.log("got response " + JSON.stringify(reserveInfo));
+          reserve.current_amount = reserveInfo.balance;
+          let tx = db.transaction(['reserves'], 'readwrite');
+          console.log("putting updated reserve " + JSON.stringify(reserve));
+          tx.objectStore('reserves').put(reserve);
+          tx.oncomplete = (e) => {
+            resolve(reserve);
+          };
+        }
+      });
+    };
+  });
+
+}
+
+
+/**
+ * Update or add mint DB entry by fetching the /keys information.
+ * Optionally link the reserve entry to the new or existing
+ * mint entry in then DB.
+ */
+function updateMintFromUrl(db, baseUrl) {
+  console.log("base url is " + baseUrl);
+  let reqUrl = URI("keys").absoluteTo(baseUrl);
+  let myRequest = new XMLHttpRequest();
+  myRequest.open('get', reqUrl.href());
+  myRequest.send();
+  return new Promise((resolve, reject) => {
+    myRequest.addEventListener('readystatechange', (e) => {
+      console.log("state change to " + myRequest.readyState);
+      if (myRequest.readyState == XMLHttpRequest.DONE) {
+        if (myRequest.status == 200) {
+          console.log("got /keys");
+          let mintKeysJson = JSON.parse(myRequest.responseText);
+          if (!mintKeysJson) {
+            console.log("keys invalid");
+            reject();
+          } else {
+            let mint = {};
+            mint.baseUrl = baseUrl;
+            mint.keys = mintKeysJson;
+            let tx = db.transaction(['mints'], 'readwrite');
+            tx.objectStore('mints').put(mint);
+            tx.oncomplete = (e) => {
+              resolve(mint);
+            };
+          }
+        } else {
+          console.log("/keys request failed with status " + myRequest.status);
+          // XXX: also write last error to DB to show in the UI
+          reject();
+        }
+      }
+    });
+  });
 }
 
 
@@ -127,20 +307,16 @@ function dumpDb(db, detail, sendResponse) {
   return true;
 }
 
-withTalerDb((db) => {
+
+openTalerDb().then((db) => {
   console.log("db loaded");
   chrome.runtime.onMessage.addListener(
     function (req, sender, onresponse) {
-      // XXX: use assoc. instead of switch?
-      switch (req.type)
-      {
-        case "confirm-reserve":
-          return confirmReserve(db, req.detail, onresponse)
-          break;
-        case "dump-db":
-          console.log('dumping db');
-          return dumpDb(db, req.detail, onresponse);
+      let dispatch = {
+        "confirm-reserve": confirmReserve,
+        "dump-db": dumpDb
       }
+      return dispatch[req.type](db, req.detail, onresponse);
     });
 });
 

extension/pages/confirm-create-reserve.html

@@ -15,7 +15,7 @@
     <div class='formish'>
       <div class='form-row'>
         <label for='mint-url'>Mint URL</label>
-        <input class='url' id='mint-url' type="text"></input>
+        <input class='url' id='mint-url' type="text" value="http://mint.demo.taler.net/"></input>
       </div>
       <button id='confirm'>Confirm Reserve</button>
     </div>

extension/pages/debug.html

@@ -0,0 +1,10 @@
+<!doctype html>
+<html>
+  <head>
+    <title>Taler Wallet Debugging</title>
+  </head>
+  <body>
+    <h1>Debug Pages</h1>
+    <a href="show-db.html">Show DB</a>
+  </body>
+</html>

extension/popup/wallet.html

@@ -13,6 +13,7 @@
       <a href="wallet.html" class="active">Wallet</a>
       <a href="transactions.html">Transactions</a>
       <a href="reserves.html">Reserves</a>
+      <button id="debug">Debug!</button>
     </div>
 
     <div id="content">

extension/popup/wallet.js

@@ -78,20 +78,23 @@ function update_currency (currency, amount)
   checkbox._amount = amount;
 }
 
-document.addEventListener(
-  'DOMContentLoaded',
-  function () {
-    chrome.runtime.sendMessage({type: "WALLET_GET"}, function(wallet) {
-      for (let currency in wallet)
-      {
-        let amount = amount_format(wallet[currency]);
-        add_currency(currency, amount);
-      }
-    });
-
-    // FIXME: remove
-    add_currency('EUR', 42);
-    add_currency('USD', 17);
-    add_currency('KUD', 1337);
-    update_currency('USD', 23);
+document.addEventListener('DOMContentLoaded', (e) => {
+  chrome.runtime.sendMessage({type: "WALLET_GET"}, function(wallet) {
+    for (let currency in wallet) {
+      let amount = amount_format(wallet[currency]);
+      add_currency(currency, amount);
+    }
   });
+
+  // FIXME: remove
+  add_currency('EUR', 42);
+  add_currency('USD', 17);
+  add_currency('KUD', 1337);
+  update_currency('USD', 23);
+
+  document.getElementById("debug").addEventListener("click", (e) => {
+    chrome.tabs.create({
+      "url": chrome.extension.getURL("pages/debug.html")
+    }); 
+  });
+});