JavaScript® Bible, Sixth Edition

Chapter 46. Security and Netscape Signed Scripts

IN THIS CHAPTER

• Exploring browser security policies

• Applying JavaScript to Navigator security mechanisms

• Using Netscape signed scripts

The paranoia levels about potential threats to security and privacy on the Internet are at an all-time high. As more people rely on e-mail and web site content for their daily lives and transactions, the fears will only increase for the foreseeable future (an indeterminate number of web weeks). As a jokester might say, however, "I may be paranoid, but how do I know someone really isn't out to get me?" The answer to that question is that you don't know, and such a person may be out there.

But web software developers are doing their darnedest to put up roadblocks to those persons out to get you—hence, the many levels of security that pervade browsers. Unfortunately, these roadblocks also get in the way of scripters who have completely honest intentions. Designing a web site around these barriers is one of the greatest challenges that many scripters face.

Battening Down the Hatches

When Navigator 2 first shipped to the world way back in the previous century (February 1996), it was the first browser released to include support for Java applets and scripting—two entirely different but often confused technologies. It didn't take long for clever programmers in the Internet community to find the ways in which one or the other technology provided inadvertent access to client computer information (such as reading file ...