User IP Hashes are now salted with 24 bits from a cryptographically secure random generation function formatted into base 64 for extra privacy/security.

src/app/chatPreprocessor.js

@@ -132,7 +132,6 @@ class chatPreprocessor{
         commandObj.links = [];
 
         //For each link sent from the client
-        //this.rawData.links.forEach((link) => {
         for (const link of commandObj.rawData.links){
             //Add a marked link object to our links array
             commandObj.links.push(await linkUtils.markLink(link));

src/schemas/user/userBanSchema.js

@@ -73,8 +73,6 @@ const userBanSchema = new mongoose.Schema({
  * @returns {Mongoose.Document} Found ban Document if one exists.
  */
 userBanSchema.statics.checkBanByIP = async function(ip){
-    //Get hash of ip
-    const ipHash = hashUtil.hashIP(ip);
     //Get all bans
     const banDB = await this.find({});
     //Create null variable to hold any found ban
@@ -106,7 +104,7 @@ userBanSchema.statics.checkBanByIP = async function(ip){
             const curHash = ban.ips.hashed[ipIndex];
 
             //Check the current hash against the given hash
-            if(ipHash == curHash){
+            if(hashUtil.compareIPHash(ip, curHash)){
                 //If it matches we found the ban
                 foundBan = ban;
 

src/schemas/user/userSchema.js

@@ -757,8 +757,6 @@ userSchema.methods.tattooIPRecord = async function(ip){
             lastLog: new Date()
         };
 
-        //We should really start using for loops and stop acting like its 2008
-        //Though to be quite honest this bit would be particularly brutal without them
         //For every user in the userlist
         for(let curUser of users){
             //Ensure we're not checking the user against itself
@@ -766,7 +764,7 @@ userSchema.methods.tattooIPRecord = async function(ip){
                 //For every IP record in the current user
                 for(let curRecord of curUser.recentIPs){
                     //If it matches the current ipHash
-                    if(curRecord.ipHash == ipHash){
+                    if(hashUtil.compareIPHash(ip, curRecord.ipHash)){
                         //Check if we've already marked the user as an alt
                         const foundAlt = this.alts.indexOf(curUser._id);
 
@@ -803,7 +801,7 @@ userSchema.methods.tattooIPRecord = async function(ip){
     //Look for matching ip record
     function checkHash(ipRecord){
         //return matching records
-        return ipRecord.ipHash == ipHash;
+        return hashUtil.compareIPHash(ip, ipRecord.ipHash);
     }
 }
 

src/utils/hashUtils.js

@@ -60,17 +60,40 @@ module.exports.compareLegacyPassword = function(pass, hash){
  * 
  * Provides a basic level of privacy by only logging salted hashes of IP's
  * @param {String} ip - IP to hash
- * @returns {String} Hashed/Peppered IP Adress
+ * @param {String} salt - (optional) string to salt IP with, leave empty to default to a securely generated string encoded in base64
+ * @returns {String} Hashed/Peppered/Salted IP Address
  */
-module.exports.hashIP = function(ip){
+module.exports.hashIP= function(ip, salt){
     //Create hash object
     const hashObj = crypto.createHash('sha512');
 
-    //add IP and pepper to the hash
-    hashObj.update(`${ip}${config.secrets.ipSecret}`);
+    //If we wheren't provided salt
+    if(salt == null){
+        //Generate salt with cryptographically secure rng function
+        const rawSalt = crypto.randomBytes(24);
+        //Convert generated salt to base64
+        salt = rawSalt.toString('base64');
+    }
 
-    //return the IP hash as a string
-    return hashObj.digest('hex');
+    //Generate new salted hash
+    hashObj.update(`${ip}${config.secrets.ipSecret}${salt}`);
+
+    //Convert hash data into a base64 string
+    const hash = hashObj.digest('base64');
+
+    //Return salty hash
+    return `${salt}$${hash}`;
+}
+
+module.exports.compareIPHash = function(ip, hash){
+    //Split hash by salt delimiter
+    const splitHash = hash.split("$");
+
+    //Re-generate hash from received plaintext IP and salt scraped from existing hash
+    const tempHash = module.exports.hashIP(ip, splitHash[0]);
+
+    //If the hash we calculates matches the original
+    return tempHash == hash;
 }
 
 /**