Comprehensive cryptography guidance covering encryption algorithms, password hashing, TLS configuration, key management, and post-quantum considerations. Use when implementing encryption, choosing hashing algorithms, configuring TLS/SSL, managing cryptographic keys, or reviewing cryptographic implementations.
View on GitHubJanuary 21, 2026
Select agents to install to:
npx add-skill https://github.com/melodic-software/claude-code-plugins/blob/main/plugins/security/skills/cryptography/SKILL.md -a claude-code --skill cryptographyInstallation paths:
.claude/skills/cryptography/# Cryptography Comprehensive guidance for implementing cryptographic operations securely, covering encryption algorithms, password hashing, TLS, and key management. ## When to Use This Skill Use this skill when: - Choosing encryption algorithms - Implementing password hashing - Configuring TLS/SSL - Managing cryptographic keys - Implementing digital signatures - Generating random values - Reviewing cryptographic implementations - Considering post-quantum readiness ## Algorithm Quick Reference ### Encryption Algorithms | Algorithm | Type | Key Size | Use Case | Status | |-----------|------|----------|----------|--------| | AES-256-GCM | Symmetric | 256 bits | Data encryption | ✅ Recommended | | ChaCha20-Poly1305 | Symmetric | 256 bits | Data encryption (mobile) | ✅ Recommended | | RSA-OAEP | Asymmetric | 2048+ bits | Key exchange | ✅ Recommended | | ECDH (P-256) | Asymmetric | 256 bits | Key agreement | ✅ Recommended | | X25519 | Asymmetric | 256 bits | Key agreement | ✅ Recommended | | DES | Symmetric | 56 bits | None | ❌ Deprecated | | 3DES | Symmetric | 168 bits | Legacy only | ⚠️ Avoid | | Blowfish | Symmetric | 32-448 bits | None | ⚠️ Avoid | ### Signature Algorithms | Algorithm | Type | Key Size | Use Case | Status | |-----------|------|----------|----------|--------| | Ed25519 | EdDSA | 256 bits | Signatures | ✅ Recommended | | ECDSA (P-256) | ECC | 256 bits | Signatures, JWT | ✅ Recommended | | RSA-PSS | RSA | 2048+ bits | Signatures | ✅ Recommended | | RSA PKCS#1 v1.5 | RSA | 2048+ bits | Legacy signatures | ⚠️ Use PSS instead | ### Hash Functions | Algorithm | Output Size | Use Case | Status | |-----------|-------------|----------|--------| | SHA-256 | 256 bits | General hashing | ✅ Recommended | | SHA-384 | 384 bits | Higher security | ✅ Recommended | | SHA-512 | 512 bits | Highest security | ✅ Recommended | | SHA-3-256 | 256 bits | Alternative to SHA-2 | ✅ Recommended | | BLAKE2b | 256-512 bits | Fast hashing | ✅ Recommended | | MD5 | 128 bits