How LSIG Works

LSIG is a simple implementation of Lamport signatures designed for quantum-resistant digital signatures. Here's how it operates:

1. Private Key Generation:

   • A private key is randomly generated

2. Public Key Derivation:

   • The public key is derived by hashing the private key using a secure hash function.
   • This ensures that the public key is securely derived from the private key, providing a one-way mapping.

3. Message Signing:

   • To sign a message, it is first hashed using a secure hash function (e.g., SHA-256).

   • The hash value is then used to reveal preimages based on the bit representation of the message.

   • These preimages serve as the signature blocks.

4. Signature Verification:

   • To verify a signature, each block of the signature is hashed.
   • The resulting hash values are compared against the corresponding blocks of the public key.
   • If the hash values match, the signature is considered valid, confirming the authenticity of the message.

Limitations

• Key Reuse: Using the same key pair to sign multiple messages may lead to revealing a significant portion of the private key.