]> git.immae.eu Git - perso/Immae/Projets/Cryptomonnaies/BIP39.git/blobdiff - src/js/index.js
Duplicate card detection is case insensitive
[perso/Immae/Projets/Cryptomonnaies/BIP39.git] / src / js / index.js
index 107610886fd24debf758a4f789c7795832653448..6a81601cd5c738b5abc8f4504d5cce59575e4e84 100644 (file)
         }
         // Discard trailing entropy
         var bitsToUse = Math.floor(bits.length / 32) * 32;
-        var binaryStr = bits.substring(0, bitsToUse);
+        var start = bits.length - bitsToUse;
+        var binaryStr = bits.substring(start);
         // Convert entropy string to numeric array
         var entropyArr = [];
         for (var i=0; i<binaryStr.length / 8; i++) {
         // If time to crack is less than one day, and password is considered
         // strong or better based on the number of bits, rename strength to
         // 'easily cracked'.
-        var z = zxcvbn(entropy.cleanStr);
-        var timeToCrack = z.crack_times_seconds.offline_fast_hashing_1e10_per_second;
-        if (timeToCrack < 86400 && entropy.binaryStr.length >= 128) {
-            strength = "easily cracked";
-            if (z.feedback.warning != "") {
-                strength = strength + " - " + z.feedback.warning;
-            };
-        }
-        var bitsStr = entropy.binaryStr.length;
+        try {
+            var z = zxcvbn(entropy.base.parts.join(""));
+            var timeToCrack = z.crack_times_seconds.offline_fast_hashing_1e10_per_second;
+            if (timeToCrack < 86400 && entropy.binaryStr.length >= 128) {
+                strength = "easily cracked";
+                if (z.feedback.warning != "") {
+                    strength = strength + " - " + z.feedback.warning;
+                };
+            }
+        }
+        catch (e) {
+            strength = "unknown";
+            console.log("Error detecting entropy strength with zxcvbn:");
+            console.log(e);
+        }
+        var bitsStr = getNumberOfEntropyBits(entropy);
         var wordCount = Math.floor(entropy.binaryStr.length / 32) * 3;
-        DOM.entropyFiltered.text(entropy.cleanStr);
-        DOM.entropyType.text(entropy.base.str);
+        var entropyTypeStr = getEntropyTypeStr(entropy);
+        DOM.entropyFiltered.html(entropy.cleanHtml);
+        DOM.entropyType.text(entropyTypeStr);
         DOM.entropyStrength.text(strength);
         DOM.entropyEventCount.text(entropy.base.ints.length);
         DOM.entropyBits.text(bitsStr);
         DOM.entropyBitsPerEvent.text(Math.log2(entropy.base.asInt).toFixed(2));
     }
 
+    function getNumberOfEntropyBits(entropy) {
+        var bitsStr = entropy.binaryStr.length.toString();
+        // If using cards, assume they are not reused, thus additional entropy
+        // decreases as more cards are used. This means entropy is measured
+        // using n!, not base^n.
+        // eg the second last card can be only one of two, not one of fifty two
+        // so the added entropy for that card is only one bit at most
+        if (entropy.base.asInt == 52) {
+            var totalDecks = Math.ceil(entropy.base.parts.length / 52);
+            var totalCards = totalDecks * 52;
+            var totalCombos = factorial(52).pow(totalDecks);
+            var totalRemainingCards = totalCards - entropy.base.parts.length;
+            var remainingDecks = Math.floor(totalRemainingCards / 52);
+            var remainingCards = totalRemainingCards % 52;
+            var remainingCombos = factorial(52).pow(remainingDecks) * factorial(remainingCards);
+            var currentCombos = totalCombos.divide(remainingCombos);
+            bitsStr = currentCombos.toString(2).length.toString();
+        }
+        return bitsStr
+    }
+
+    function getEntropyTypeStr(entropy) {
+        var typeStr = entropy.base.str;
+        // Add some detail if these are cards
+        if (entropy.base.asInt == 52) {
+            var cardDetail = []; // array of message strings
+            // Detect duplicates
+            var dupes = [];
+            var dupeTracker = {};
+            for (var i=0; i<entropy.base.parts.length; i++) {
+                var card = entropy.base.parts[i];
+                var cardUpper = card.toUpperCase();
+                if (cardUpper in dupeTracker) {
+                    dupes.push(card);
+                }
+                dupeTracker[cardUpper] = true;
+            }
+            if (dupes.length > 0) {
+                var dupeWord = "duplicates";
+                if (dupes.length == 1) {
+                    dupeWord = "duplicate";
+                }
+                var msg = dupes.length + " " + dupeWord + ": " + dupes.slice(0,3).join(" ");
+                if (dupes.length > 3) {
+                    msg += "...";
+                }
+                cardDetail.push(msg);
+            }
+            // Detect full deck
+            var uniqueCards = [];
+            for (var uniqueCard in dupeTracker) {
+                uniqueCards.push(uniqueCard);
+            }
+            if (uniqueCards.length == 52) {
+                cardDetail.unshift("full deck");
+            }
+            // Add card details to typeStr
+            if (cardDetail.length > 0) {
+                typeStr += " (" + cardDetail.join(", ") + ")";
+            }
+        }
+        return typeStr;
+    }
+
+    // Depends on BigInteger
+    function factorial(n) {
+        if (n == 0) {
+            return 1;
+        }
+        f = BigInteger.ONE;
+        for (var i=1; i<=n; i++) {
+            f = f.multiply(new BigInteger(i));
+        }
+        return f;
+    }
+
     var networks = [
         {
             name: "Bitcoin",