7. Sandboxing Native Code

TL;DR

Native Client uses software fault isolation and strict rules to ensure the safety and security of web applications.

Transcript

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Key Insights

• 😒 Native Client uses software fault isolation to enforce safety and security in web applications.
• 👨‍💻 The system relies on strict rules for jumps and returns to prevent unsafe execution of code.

Questions & Answers

Q: Why does Native Client want to run native code in the browser?

Running native code allows for faster computation and the ability to run existing code or use different programming languages.

Q: How does Native Client ensure that instructions are safe to execute?

It uses software fault isolation and checks for disallowed instructions, ensures all code and data accesses are in bounds, and adds instrumentation to potentially unsafe instructions to make them safe.

Q: How does Native Client handle jumps and returns?

Native Client enforces specific rules for jumps to ensure that they are valid and jumps to indirect addresses are checked for validity. Returns must be preceded by a specific pseudo instruction to ensure they are safe to execute.

Summary & Key Takeaways

• Native Client is a system used by Google that allows web applications to run native code in the browser.

• The system relies on software fault isolation to ensure the safety and security of the code.

• To enforce safety, Native Client checks for disallowed instructions, ensures all code and data accesses are in bounds, and follows specific rules for jumps and returns.