What problem does it solve? Cryptographic implementations are notoriously difficult to get right, and small bugs can expose private keys, allow signature forgery, or create consensus problems. This Skill guides you through using the Wycheproof test vector collection to systematically validate crypto code against known attacks and edge cases. ## Core Features & Use Cases - Test Vector Integration: Add Wycheproof as a git submodule or fetch specific JSON test vectors for algorithms like AES-GCM, ECDSA, ECDH, RSA, and ChaCha20-Poly1305. - Testing Harness Patterns: Parse test vectors and write parameterized test harnesses in Python/pytest or JavaScript/Mocha that handle valid, invalid, and acceptable result types. - Vulnerability Detection: Catch signature malleability, invalid DER encoding, invalid curve attacks, padding oracles, and tag forgery, as demonstrated by real CVEs found in the elliptic npm package. - Use Case: You are auditing a JavaScript library's EdDSA implementation. Use this Skill to load ed25519_test.json, generate parameterized tests, and discover that the library accepts signatures with trailing zeros (signature malleability). ## Quick Start Ask the AI to set up Wycheproof test vectors for your AES-GCM implementation and write a pytest harness that validates both encryption and decryption against all test cases.
