Implementation Guide: Signing Tools with SHA-256

A step-by-step guide to how the kernel signs tools with SHA-256 and updates the signature after the AST engine performs a repair.

When is the signature created?

After a tool is generated and verified successfully. A tool that fails verification is not signed as a trusted tool.

What happens if the code changes?

The signature changes. A changed signature means the code must be verified again before it can be trusted.

Is signing a substitute for verification?

No. Signing detects change; verification confirms the outcome. They are separate layers of the same security model.

Who updates the signature?

The AST engine updates the signature after it applies a repair to the code. The kernel then returns to a stable state.

What is the scope of signing?

Every tool is signed. The signature acts as a tamper-evident seal for the tool code.