Module crypto 

Password-based encryption for built sites: AES-256-GCM + PBKDF2.

Pure (§2.1): no I/O, no filesystem. encrypt takes plaintext + password + an injected rng and returns an EncryptedPayload; decrypt takes a payload + password and returns the plaintext. The rng is injected so the whole transform is deterministic given the rng’s output (testable, no global randomness source).

The browser-side decryption uses the same algorithm via WebCrypto (crypto.subtle.deriveKey + crypto.subtle.decrypt), so a payload encrypted in Rust decrypts in the browser and vice versa (ADR-0012).

Structs

EncryptedPayload

An encrypted payload: the ciphertext plus the salt and nonce needed to decrypt it (§1.2 — a represented state, not a bag of bytes).

Enums

CryptoError

Why decryption failed — the password was wrong, the payload is corrupt, or the base64 encoding is malformed.

Constants

PBKDF2_ITERATIONS

PBKDF2 iteration count — 600,000 with HMAC-SHA-256 (OWASP 2023 recommendation for PBKDF2-SHA256). The same literal appears in the decrypt shell’s inline JS so the browser-side WebCrypto derivation matches.

Functions

decrypt

Decrypt an EncryptedPayload with password.

encrypt

Encrypt plaintext with password, using rng to generate a fresh salt and nonce (§2.1 — pure w.r.t. rng: the rng is the only source of nondeterminism).