Signatures in the Wild: Code Signing & Email
Explore S/MIME, PGP, and how software is signed for distribution.
Welcome
Digital signatures protect software distribution and email communication. In this lesson we trace exactly how code signing and email signing work in practice.
macOS Code Signing
Apple Developer certificates contain an RSA/ECDSA public key. Xcode signs each app: signature = Sign(SHA256(app_bundle), dev_private_key). macOS Gatekeeper verifies before launch.
All lessons in this course
- What Is a Digital Signature?
- RSA Signatures: Sign & Verify
- DSA & ECDSA Signature Schemes
- Signatures in the Wild: Code Signing & Email