Saturday, August 22, 2015

Camping and Website Authentication

Just got back from vacation and had a great time. We traveled up to Traverse City to see my Grandma and cousin; then stopped by Mackinac Island with our bikes to stay the night; then finally arrived at our destination in Tahquamenon Falls to spend the rest of the week camping with my dad, sisters, and brother-in-law.

After getting back home, I finally got around to adding authentication to my website (salgat.net/Manager). While ASP.NET comes with several forms of authentication support built in, I decided to do it the old fashioned way as a quick learning experience. 

Implementing authentication was done using both the Session state and a User SQL table. The table has a UserName, Salt, Hashed (Password+Salt), and Authentication Level stored. When the user goes to the Manager webpage, if they are not authenticated, they are sent to the Login page. In the login page, they submit a username and password, where the username is found in the table, its corresponding salt is found and appended to the provided password, and that value is hashed and compared against the stored hash value. If they both match, the Session collection is updated with the UserName and Authentication level. When the user tries to access any protected pages, the Authentication level stored in Session is checked, and if it fails, the user is redirected to the login page.

Login page located at www.salgat.net/Manager/Login.aspx


The purpose of not storing the raw password in the database is to prevent a database breach from resulting in user's passwords being visible to the hackers, which, while not very helpful for security of your own website, prevents a user's username/password from being used on other websites. The salt is used as a way to prevent rainbow tables from allowing for easy password lookups on the database, since the hacker would have to create unique rainbow tables for each user.

As a final note, it should go without saying that doing any of this is a really bad idea unless you know exactly what you are doing. Security is an extremely serious topic and, unless you are an expert, should not be done in any serious setting. Additionally, any security related programming should be regularly audited by a third party security company/consultant.

Sunday, August 9, 2015

Update to ASP.NET

Last month I updated my website (mostly to present my projects better). The upgrade included using a free template I found online and then manually creating each page in HTML. The result looked alright but it was a pain to change most of the pages. If I wanted to add a new page, I had to update all the pages with the added link in the header. Or, if I wanted to insert a new project, I had to update the project index present at the bottom of all the project pages. Worse yet, it was very easy for one mistake to occur in all the copy and pasting.

I decided to upgrade to an ASP.NET Web App. The first step was finding all the common elements between each page and moving them to a single Master Page. The beauty of this is that if I need to add a new page to the navigation bar, I simply update the Master Page. Additionally, the projects directory has its own Master Page nested inside the main website's Master Page. It programmatically generates the project directory present at the bottom of each project page which makes things so much easier to update.



Finally, I was able to migrate to Microsoft's Azure web hosting platform. Previously, I had been using Dreamhost's VPS and a simple apache server that pointed to a root directory containing my static website. Now, the website is dynamically generated and updating the website is as easy as clicking the "Publish" button in Visual Studio.

As a final note, I decided to have a little fun with the site and added an web site manager page located at http://www.salgat.net/Manager/. It's nothing fancy, but I added a view count tracker using a SQL database that holds a ViewCount entry that is incremented every time a new session is started. I don't actually care much about this (I'm sure most of the views are just web crawlers anyways) but it's a great chance to learn more. I think from here I'm going to add a login for the page and do things like have a table of unique IPs stored with a view count associated with each IP. What's nice is that I'm using the Azure hosting platform again for hosting the database. I was pretty impressed with the pricing, as the combined cost of the web app hosting and database hosting is roughly the same as a VPS with Dreamhost, which means I'll drop Dreamhost's VPS hosting altogether and just use it as a domain provider.

For those who want to check out the progress, I have the project hosted on GitHub. I made sure to use .gitignore for things like Web.config to prevent secure information (database password) from being released.

https://github.com/Salgat/Personal-Website