secure_data

Secrets management, envelope encryption, password hashing, and FIPS-ready cryptography (OWASP C8). Part of the SunLit Security Libraries workspace.

When to reach for this crate

You handle secrets in-memory (API tokens, DB passwords, signing keys) and want types that suppress Debug, Display, and default Serialize and that zero on drop.
You need envelope encryption with a pluggable KMS (Vault, AWS KMS, Azure Key Vault, or a static dev key).
You need Argon2id password hashing (OWASP C2/C7) without re-deriving parameters every release.
You want FIPS 140-2/3 readiness by toggling a feature flag (aws-lc-rs backend).
You want mobile secure storage primitives (SensitiveBuffer, BackupExclusion, MASVS-STORAGE-1).

Install

[dependencies]
secure_data = { version = "0.1.2", features = ["password"] }

Quick examples

Typed secret wrappers

use secure_data::secret::SecretString;

let token = SecretString::new("super-secret-api-key".to_owned());
println!("{:?}", token);  // -> SecretString([REDACTED])
// Only call expose_secret() at the boundary that actually needs the bytes.
let bytes = token.expose_secret();

Argon2id password hashing (`features = ["password"]`)

use secure_data::password::{hash_password, verify_password};
use secure_data::secret::SecretString;

let password = SecretString::new("correct-horse-battery".to_owned());
let hash = hash_password(&password)?;
assert!(verify_password(&password, &hash)?);
# Ok::<(), Box<dyn std::error::Error>>(())

Envelope encryption with a key provider

use secure_data::envelope::{encrypt_for_storage, decrypt_for_use};
use secure_data::kms::StaticDevKeyProvider;
use std::sync::Arc;

let kms = Arc::new(StaticDevKeyProvider::with_dev_key());
let plaintext = b"private medical record";

let envelope = encrypt_for_storage(&*kms, "phi:patient:42", plaintext)?;
// envelope.ciphertext is AES-256-GCM, envelope.wrapped_dek is the KMS-wrapped DEK.

let recovered = decrypt_for_use(&*kms, &envelope)?;
assert_eq!(recovered.as_slice(), plaintext);
# Ok::<(), Box<dyn std::error::Error>>(())

What's inside

Module	Use it for
`secret`	`SecretString`, `SecretBytes`, `ApiToken`, `DbPassword`, `SigningKeyRef` — types that won't leak via Debug/Display/Serialize and zero on drop.
`envelope`	`encrypt_for_storage`, `decrypt_for_use` — AES-256-GCM envelope encryption.
`kms`	`KeyProvider` trait + `StaticDevKeyProvider` for tests.
`providers`	Real KMS providers (Vault, AWS KMS) gated by features.
`keyring`	Logical key registry with aliases, versions, and lifecycle (`Active`, `RotatingFrom`, `Deprecated`).
`rotation`	Re-encryption helpers for key rotation with dual-read.
`algorithm`	`CryptoAlgorithm`, `AlgorithmPolicy` — algorithm selection and downgrade prevention.
`password`	Argon2id `hash_password` / `verify_password` (feature `password`).
`config` / `resolve`	`vault://`, `kms://`, `env://` reference parsing and resolution.
`memory`	`Zeroize` and `ReadOnce` helpers.
`serde`	Safe serializers for secret-bearing structs.
`mobile_storage`	`SensitiveBuffer`, `BackupExclusion`, `MobileStoragePolicy` (feature `mobile-storage`, MASVS-STORAGE-1).

Feature flags

Flag	Dependency	Purpose
`vault`	`reqwest`	HashiCorp Vault Transit key provider + KV secret resolution.
`aws-kms`	`aws-sdk-kms`, `aws-config`	AWS KMS `GenerateDataKey` / `Decrypt` provider.
`azure-kv`	—	Azure Key Vault key provider (wrap/unwrap only).
`fips`	`aws-lc-rs`	FIPS 140-2/3 validated AEAD backend.
`password`	`argon2`	Argon2id password hashing.
`mobile-storage`	—	Mobile secure-storage primitives (MASVS-STORAGE).

All features are off by default. Combine freely: cargo add secure_data --features vault,aws-kms,password.

Compatibility

MSRV: 1.78
#![forbid(unsafe_code)], #![deny(missing_docs)]
Zeroize-on-drop wherever a secret is held

Status

Alpha.

Related crates

Part of the SunLit Security Libraries workspace:

Crate	Purpose
`security_core`	Shared types, identity, classification, severity, redaction.
`security_events`	Security logging and tamper-evident audit chain.
`secure_errors`	Three-layer error model with redaction-safe public errors.
`secure_output`	Context-aware output encoders (HTML, JSON, URL, JS, CSS, XML, LDAP, shell).
`secure_network`	TLS policy, SPKI pinning, mTLS, cleartext detection.
`secure_device_trust`	Native-client device trust and session certificates.
`secure_resilience`	RASP and environment-detection policy.
`secure_privacy`	PII classification, consent, retention, pseudonymization.
`secure_boundary`	Input validation, security headers, boundary protections.
`secure_identity`	JWT/OIDC, MFA, sessions, biometric step-up.
`secure_authz`	Typed deny-by-default authorization with device-trust predicates.

Getting help

Questions, ideas, design discussions — open a GitHub Discussion.
Bug reports — use the bug-report template in GitHub Issues.
Security issues — please do not open a public issue. See SECURITY.md for the responsible-disclosure process.

Contributing

Contributions are welcome. Please read CONTRIBUTING.md and the Code of Conduct before opening a PR.

License

Dual-licensed under MIT or Apache-2.0 at your option.

secure_data 0.1.2