Cryptographic Signature Integrity via Spatial Redundancy

The patent creates redundant copies of cryptographic secrets (specifically the polynomial s1 and seed rho) and stores them in separate memory locations. Before signature generation, the system retrieves these secrets from multiple locations and verifies they match. This copying approach provides fault detection capability with minimal performance overhead compared to temporal redundancy, as it avoids re-executing the entire signature generation process.

The patent performs verification of cryptographic secret integrity before the signature generation process begins. Specifically, it retrieves redundant copies of the secrets, compares them to ensure they match, and only proceeds with signature generation if verification succeeds. This preliminary action prevents faulty signatures from being generated in the first place, eliminating the need for post-generation verification and reducing overall performance overhead.

The patent applies redundancy selectively to specific cryptographic secrets that are most vulnerable to Rowhammer attacks, namely the polynomial s1 and seed rho used in the Dilithium signing process. Rather than redundantly storing all cryptographic data, it focuses redundancy on these critical elements. The redundant copies are stored in physically separate memory locations to maximize protection against localized faults, balancing detection probability with memory overhead.