RSA Signatures: Sign & Verify
Step through the math of signing a document hash with a private key.
Welcome
RSA signatures flip the key roles: the private key signs and the public key verifies. This enables anyone to verify your identity using your public key.
RSA Signing Math
To sign message M with private key (d, n):
1. H = SHA256(M)
2. sig = H^d mod n
The signature is a number with the same bit length as n.
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