How to generate keys with the Web Cryptography API

I have been playing around with the Web Cryptography API a lot lately.  My most recent post was about getRandomValues().  I wanted to take a moment to investigate two more methods: generateKey() and exportKey().  The generation of a good cryptographic key is fairly fundamental.  I wrote up a short demo app, to demonstrate how the two …

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Generating random numbers with the Web Cryptography API

The W3C has been working on a Web Cryptography API for a while, now.  The current version (11 December 2014) is their “Candidate Recommendation”.  As such, I would not necessarily consider it fully ready for primetime but that does not mean that we can not play around with it a bit.  I figured that today, we should …

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How to use FileReader() to generate data URLs

These days, the lines between the web and the local environment can be very blurry.  There is a web API called FileReader() that nicely adds to that blurriness.  It lets you asynchronously read the contents of a file on the user’s computer.  I am going to show you one way of using it.     So, …

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An unofficial Security Now episode explorer

Well, I finished another PhoneGap Build app.  This is another “Joe scratches his own itch” app.  It’s an app that shows the entire Security Now back catalog and lets you browse through the various topics. This is the final app in my 30 day challenge, so my pace of new development is going to slow …

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How do you sign a PhoneGap app?

This is a quick thing.  When you build an app in PhoneGap Build, it asks for a keystore file.  So, how do you get one?  Here is the command for on the mac. keytool -genkey -v -keystore [Name for the file].keystore -alias [Name for the app] -keyalg RSA -keysize 2048 -validity 10000 Remember to replace [Name …

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How to use localStorage to remember form values

Since finishing my last post, I’ve been wanting to work on a way of implementing the concepts.  Let’s say you have a long form (like a job application) or a form you would be filling out a lot (like shipping/billing information).  You could use ajax to store the information server-side but let’s say you need or want …

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