diff --git a/node/db/Pad.js b/node/db/Pad.js
index bba7562c8..0db0a9bda 100644
--- a/node/db/Pad.js
+++ b/node/db/Pad.js
@@ -489,9 +489,13 @@ Class('Pad', {
this.passwordHash = password == null ? null : hash(password, generateSalt());
db.setSub("pad:"+this.id, ["passwordHash"], this.passwordHash);
},
+ getPasswordSalt: function()
+ {
+ return this.passwordHash.split("$")[1];
+ },
isCorrectPassword: function(password)
{
- return compare(this.passwordHash, password)
+ return timeSensitiveCompare(this.passwordHash, password)
},
isPasswordProtected: function()
{
@@ -512,17 +516,21 @@ function hash(password, salt)
function generateSalt()
{
var len = 86;
- var chars = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz./";
+ var charset = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz./";
var randomstring = '';
for (var i = 0; i < len; i++)
{
- var rnum = Math.floor(Math.random() * chars.length);
- randomstring += chars.substring(rnum, rnum + 1);
+ var rnum = Math.floor(Math.random() * charset.length);
+ randomstring += charset[rnum];
}
return randomstring;
}
-function compare(hashStr, password)
+/* Compare the timed password hash with the saved value.
+ * If the hash was generated too far in the past, it is rejected. */
+function timeSensitiveCompare(hashStr, password)
{
- return hash(password, hashStr.split("$")[1]) === hashStr;
+ var timestamp = password.split("$")[1];
+ return password === hash(hashStr, timestamp)
+ && timestamp - new Date().getTime() > 0;
}
diff --git a/node/db/SecurityManager.js b/node/db/SecurityManager.js
index 7ad8f8d25..a8d2e89ad 100644
--- a/node/db/SecurityManager.js
+++ b/node/db/SecurityManager.js
@@ -51,6 +51,7 @@ exports.checkAccess = function (padID, sessionID, token, password, callback)
var groupID = padID.split("$")[0];
var padExists = false;
var validSession = false;
+ var pwsalt;
var sessionAuthor;
var tokenAuthor;
var isPublic;
@@ -131,6 +132,9 @@ exports.checkAccess = function (padID, sessionID, token, password, callback)
//is it password protected?
isPasswordProtected = pad.isPasswordProtected();
+
+ //get the password salt used by the hash function
+ pwsalt = pad.getPasswordSalt();
//is password correct?
if(isPasswordProtected && password && pad.isCorrectPassword(password))
@@ -162,13 +166,14 @@ exports.checkAccess = function (padID, sessionID, token, password, callback)
else if(isPasswordProtected && passwordStatus == "wrong")
{
//--> deny access, ask for new password and tell them that the password is wrong
- statusObject = {accessStatus: "wrongPassword"};
+ //The salt can be safely shared since it is not secret. It does its job (improving resistence against rainbow table attacks) even when public.
+ statusObject = {accessStatus: "wrongPassword", passwordSalt: pwsalt};
}
//- the pad is password protected but no password given
else if(isPasswordProtected && passwordStatus == "notGiven")
{
//--> ask for password
- statusObject = {accessStatus: "needPassword"};
+ statusObject = {accessStatus: "needPassword", passwordSalt: pwsalt};
}
else
{
diff --git a/static/js/pad2.js b/static/js/pad2.js
index 9df57ae8f..d21c43748 100644
--- a/static/js/pad2.js
+++ b/static/js/pad2.js
@@ -72,7 +72,7 @@ function randomString()
for (var i = 0; i < string_length; i++)
{
var rnum = Math.floor(Math.random() * chars.length);
- randomstring += chars.substring(rnum, rnum + 1);
+ randomstring += chars[rnum];
}
return "t." + randomstring;
}
@@ -147,10 +147,22 @@ function getUrlVars()
return vars;
}
-function savePassword()
+function hash(password, salt)
+{
+ return sha512(password + salt) + "$" + salt;
+}
+
+/* Generate the "timed hash" used to get access.
+ * The password is hashed with the database's salt, afterwards it is hashed again with a timestamp a few days in the future as "salt".
+ * The server checks the two hashe's equality as usual, but also checks whether this timestamp is still in the future (grant access)
+ * or if it has passed (deny access). This provides an saved-password expiry mechanism which is a) independent of the browser's cookie
+ * retention and b) provides some level of security against "cookie stealing" (be it by xss or otherwise): If Eve steals a cookie, she
+ * does "only" get a timed-hash lifetime access to the pad, but *not* the actual password.
+ */
+function savePassword(pwsalt)
{
//set the password cookie
- createCookie("password",$("#passwordinput").val(),null,document.location.pathname);
+ createCookie("password",hash(hash($("#passwordinput").val(), pwsalt), new Date().getTime() + 14 * 24 * 3600 * 1000),null,document.location.pathname); //FIXME some means of configuring this threshold would be really great
//reload
document.location=document.location;
}
@@ -214,13 +226,13 @@ function handshake()
{
$("#editorloadingbox").html("You need a password to access this pad " +
""+
- "");
+ "");
}
else if(obj.accessStatus == "wrongPassword")
{
- $("#editorloadingbox").html("You're password was wrong " +
+ $("#editorloadingbox").html("Your password was wrong " +
""+
- "");
+ "");
}
}