From 662026507752095417c4d122615a1aab8f52f68d Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Erkin=20Alp=20G=C3=BCney?= Date: Sat, 9 Apr 2022 21:45:45 +0300 Subject: [PATCH] add an elegant entropy check --- api/src/util/utility/passwordStrength.ts | 21 ++++++++++++++++----- 1 file changed, 16 insertions(+), 5 deletions(-) diff --git a/api/src/util/utility/passwordStrength.ts b/api/src/util/utility/passwordStrength.ts index 047df008..81ac2559 100644 --- a/api/src/util/utility/passwordStrength.ts +++ b/api/src/util/utility/passwordStrength.ts @@ -13,6 +13,7 @@ const blocklist: string[] = []; // TODO: update ones passwordblocklist is stored * - min numbers * - min symbols * - min uppercase chars + * - shannon entropy divided by password entropy * * Returns: 0 > pw > 1 */ @@ -22,28 +23,38 @@ export function checkPassword(password: string): number { // checks for total password len if (password.length >= minLength - 1) { - strength += 0.25; + strength += 0.05; } // checks for amount of Numbers if (password.count(reNUMBER) >= minNumbers - 1) { - strength += 0.25; + strength += 0.05; } // checks for amount of Uppercase Letters if (password.count(reUPPERCASELETTER) >= minUpperCase - 1) { - strength += 0.25; + strength += 0.05; } // checks for amount of symbols if (password.replace(reSYMBOLS, "").length >= minSymbols - 1) { - strength += 0.25; + strength += 0.05; } // checks if password only consists of numbers or only consists of chars if (password.length == password.count(reNUMBER) || password.length === password.count(reUPPERCASELETTER)) { strength = 0; } - + + var entropyMap; + for (let i = 0; i < password.length; i++) { + if (entropyMap[password[i]]) entropyMap[password[i]]++; + else entropyMap[password[i]] = 1; + } + + let entropies = Array(entropyMap); + + entropies.map(x => (x / entropyMap.length)); + strength += entropies.reduceRight((a, x), a - (x * Math.log2(x))) / Math.log2(password.length); return strength; }