Side-Channel Attack Référence
Référence pour timing, power, cache, et electromagnetic side-channel attacks sur cryptographic implementations.
Timing Attacks
Timing side-channels leak secret-dependent information through execution time variations. Data-dependent table lookups, branching on secret data, and variable-time arithmetic all create timing leakage. Constant-time implementations eliminate all secret-dependent control flow and memory access patterns. Modern cipher designs like ChaCha20 avoid table lookups entirely for this reason.
- table lookup
- Cache timing leaks key
- branching
- Secret-dependent branches leak
- mitigation
- Constant-time code
AES T-tablesavoid if on secretno secret-dependent opsPower and EM Attacks
Power analysis measures power consumption during cryptographic operations to recover keys. Simple Power Analysis (SPA) directly observes instruction-level leakage, while Differential Power Analysis (DPA) statistically correlates many traces. Electromagnetic emanations provide a similar side-channel. Hardware countermeasures include masking, hiding, and dual-rail logic.
- SPA
- Direct power observation
- DPA
- Statistical correlation
- masking
- Split secrets randomly
single tracemany tracesfirst-order DPA resistant