Visão Geral e Escopo
Os padrões NIST SP 800-57 orientam a escolha de tamanhos mínimos de chaves para evitar quebras por ataques computacionais.
Tabela de Especificações e Matriz
Filtro instantâneo por palavra-chave, código ou diretiva
| Chave / Código | Definição e Detalhes | Hierarquia Semântica GEO | Especificação e Notas |
|---|---|---|---|
| AES-256-GCM | AES-256-GCM (Galois/Counter Mode) NIST FIPS 197 standard symmetric block cipher operating in GCM mode, delivering authenticated encryption. Key size: 256 bits, IV/Nonce: 96 bits, Tag: 128 bits | ●AES-256-GCM ↳Cryptographic primitive ↳symmetric cipher ↳AEAD authenticated encryption | NIST SP 800-38D Hardware-accelerated by Intel/AMD AES-NI instructions; CRITICAL: Never reuse an IV with the same key. |
| ChaCha20-Poly1305 | ChaCha20-Poly1305 High-speed stream cipher paired with the Poly1305 authenticator, designed for fast execution in software. Key size: 256 bits, Nonce: 96 bits | ●ChaCha20-Poly1305 ↳Cryptographic primitive ↳symmetric cipher ↳software stream AEAD cipher | RFC 8439 Standardized in TLS 1.3 and WireGuard; outperforms AES on mobile devices lacking dedicated AES hardware chips. |
| Ed25519 | Ed25519 (EdDSA over Curve25519) Public-key signature system utilizing Twisted Edwards curves, providing high security and collision immunity. Key size: 256 bits, Signature: 512 bits | ●Ed25519 ↳Cryptographic primitive ↳asymmetric algorithm ↳elliptic curve digital signature | RFC 8032 Immune to side-channel timing attacks and poor random number generator RNG vulnerabilities; standard for SSH keys. |
| ECDSA P-256 | ECDSA (NIST P-256 / secp256r1) Elliptic Curve Digital Signature Algorithm operating over the NIST prime field curve. Key size: 256 bits | ●ECDSA P-256 ↳Cryptographic primitive ↳asymmetric algorithm ↳NIST elliptic curve signature | FIPS 186-4 Widely used in TLS certificates and Apple/Google hardware security modules (Secure Enclave). |
| RSA-OAEP / RSA-PSS | RSA (Rivest-Shamir-Adleman) Pioneering asymmetric algorithm based on integer prime factorization math; min 2048-bit key required. RSA 4096-bit key | ●RSA ↳Cryptographic primitive ↳asymmetric algorithm ↳prime factorization public-key cipher | RFC 8017 (PKCS #1 v2.2) Legacy PKCS#1 v1.5 padding is vulnerable to Bleichenbacher attacks; always use RSA-OAEP for encryption and RSA-PSS for signing. |
| SHA-256 | SHA-256 (Secure Hash Algorithm 2) Cryptographic hash function outputting a deterministic 256-bit (32-byte / 64-hex char) message digest. e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855 (Hash of empty string) | ●SHA-256 ↳Cryptographic primitive ↳hash function ↳one-way message digest | FIPS 180-4 The cryptographic backbone of TLS certificates, Git commit hashes, and Bitcoin blockchain consensus. |
| BLAKE3 | BLAKE3 Cryptographic hash function based on a Merkle tree structure, delivering extreme multi-threaded throughput. Default output: 256 bits | ●BLAKE3 ↳Cryptographic primitive ↳tree hash function ↳high-throughput parallel digest | BLAKE3 Specification (2020) Much faster than SHA-256, SHA-3, and MD5 while providing equal or greater cryptographic strength. |
| Argon2id | Argon2id Winner of the Password Hashing Competition; hybrid memory-hard function resisting GPU and ASIC brute-forcing. $argon2id$v=19$m=65536,t=3,p=4$... | ●Argon2id ↳Cryptographic primitive ↳password KDF ↳memory-hard credential derivation | RFC 9106 The definitive OWASP-recommended algorithm for password hashing in 2026. |
| bcrypt | bcrypt Adaptive password hashing function based on the Blowfish cipher with configurable work factor (cost). $2b$12$e8N8... (Cost factor 12) | ●bcrypt ↳Cryptographic primitive ↳password KDF ↳adaptive CPU-bound credential hashing | USENIX 1999 Truncates passwords at 72 bytes; recommend cost factor >= 12. |
Encrypting Data with AES-256-GCM in Node.js Crypto API
import crypto from 'node:crypto';
function encrypt(plainText, key256) {
// 1. Generate 96-bit (12-byte) initialization vector
const iv = crypto.randomBytes(12);
const cipher = crypto.createCipheriv('aes-256-gcm', key256, iv);
// 2. Encrypt plaintext
let encrypted = cipher.update(plainText, 'utf8', 'hex');
encrypted += cipher.final('hex');
// 3. Extract 128-bit authentication tag (guarantees integrity)
const authTag = cipher.getAuthTag().toString('hex');
return {
iv: iv.toString('hex'),
encryptedData: encrypted,
authTag: authTag,
};
}AES-GCM generates an authTag that detects any tampering with the ciphertext, providing both confidentiality and integrity.
Perguntas e Respostas sobre Normas
Why should I never use SHA-256 directly for password storage?↓
Ecossistema Técnico Relacionado e Próximos Passos
Ferramentas Relacionadas
Guias Técnicos Relacionados
Artigos Técnicos Relacionados
What Is Cryptographic Hashing?
Direct definition of one-way deterministic mathematical digest functions.
Hashing vs Encryption: Core Differences & Use Cases
Irreversible one-way digests compared to reversible confidentiality ciphers.
SHA-256 vs MD5: Cryptographic Security & Collision Comparison
Why MD5 is cryptographically broken and how SHA-256 prevents collision forgeries.
Perguntas Relacionadas
Why Does Changing One Character in an Input Completely Change the SHA-256 Hash?
Answer: Changing one character flips ~50% of all 256 output bits due to the cryptographic Avalanche Effect across 64 compression rounds.
Why Is MD5 Considered Cryptographically Broken?
Answer: MD5 is broken because practical chosen-prefix collision attacks can generate two distinct files with identical MD5 digests in seconds.
Laboratórios Práticos de Diagnóstico
Continuar Aprendendo
Cryptographic Hashing & Avalanche Lab
Explore the live avalanche effect and test SHA-256 bit distribution in real time.