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zlayer_secrets/
persistent.rs

1//! Persistent secrets storage using `SQLite` (via `SQLx`).
2//!
3//! Provides encrypted local storage for secrets with a single table combining
4//! secret values and metadata:
5//! - `storage_key`: Primary key in `{scope}:{name}` format
6//! - `encrypted_value`: XChaCha20-Poly1305 encrypted secret bytes
7//! - `name`, `version`, `created_at`, `updated_at`: Metadata fields
8//!
9//! # Example
10//!
11//! ```no_run
12//! use zlayer_secrets::{EncryptionKey, PersistentSecretsStore, Secret};
13//! use zlayer_secrets::{SecretsProvider, SecretsStore};
14//!
15//! # async fn example() -> zlayer_secrets::Result<()> {
16//! let key = EncryptionKey::generate();
17//! let secrets_dir = zlayer_paths::ZLayerDirs::system_default().secrets();
18//! let store = PersistentSecretsStore::open(&secrets_dir, key).await?;
19//!
20//! // Store a secret
21//! let secret = Secret::new("my-password");
22//! store.set_secret("deployment/myapp", "db-password", &secret).await?;
23//!
24//! // Retrieve a secret
25//! let retrieved = store.get_secret("deployment/myapp", "db-password").await?;
26//! # Ok(())
27//! # }
28//! ```
29
30use std::collections::HashMap;
31use std::path::Path;
32
33use async_trait::async_trait;
34use sqlx::sqlite::{SqliteConnectOptions, SqliteJournalMode, SqlitePoolOptions, SqliteSynchronous};
35use sqlx::{Row, SqlitePool};
36use tracing::{debug, info};
37
38use crate::{
39    EncryptionKey, Result, Secret, SecretMetadata, SecretsError, SecretsProvider, SecretsStore,
40};
41
42/// Default database filename when a directory is provided.
43const DEFAULT_DB_FILENAME: &str = "secrets.sqlite";
44
45/// SQL schema for the secrets table.
46const SCHEMA: &str = r"
47CREATE TABLE IF NOT EXISTS secrets (
48    storage_key TEXT PRIMARY KEY NOT NULL,
49    encrypted_value BLOB NOT NULL,
50    name TEXT NOT NULL,
51    version INTEGER NOT NULL DEFAULT 1,
52    created_at TEXT NOT NULL,
53    updated_at TEXT NOT NULL
54);
55CREATE INDEX IF NOT EXISTS idx_secrets_prefix ON secrets(storage_key);
56";
57
58/// Persistent secrets store backed by `SQLite` with encryption.
59///
60/// Secrets are encrypted using XChaCha20-Poly1305 before storage.
61/// Metadata is stored alongside secrets for inspection and auditing.
62///
63/// The store uses `SQLite` with WAL mode for concurrent access.
64pub struct PersistentSecretsStore {
65    pool: SqlitePool,
66    key: EncryptionKey,
67}
68
69impl PersistentSecretsStore {
70    /// Opens or creates a persistent secrets store at the given path.
71    ///
72    /// If `path` is a directory, the database file will be created as
73    /// `secrets.sqlite` inside that directory. If `path` is a file path,
74    /// it will be used directly.
75    ///
76    /// # Arguments
77    ///
78    /// * `path` - Path to the database file or directory
79    /// * `key` - Encryption key for encrypting/decrypting secrets
80    ///
81    /// # Errors
82    ///
83    /// Returns `SecretsError::Storage` if:
84    /// - The database cannot be created or opened
85    /// - Schema initialization fails
86    pub async fn open(path: impl AsRef<Path>, key: EncryptionKey) -> Result<Self> {
87        let path = path.as_ref();
88
89        // If the path is an existing directory, append the default database filename
90        let db_path = if path.is_dir() {
91            path.join(DEFAULT_DB_FILENAME)
92        } else {
93            path.to_path_buf()
94        };
95
96        // Ensure parent directory exists
97        if let Some(parent) = db_path.parent() {
98            std::fs::create_dir_all(parent)
99                .map_err(|e| SecretsError::Storage(format!("Failed to create directory: {e}")))?;
100        }
101
102        // Configure SQLite connection with WAL mode for better concurrency
103        let options = SqliteConnectOptions::new()
104            .filename(&db_path)
105            .create_if_missing(true)
106            .journal_mode(SqliteJournalMode::Wal)
107            .synchronous(SqliteSynchronous::Normal)
108            .busy_timeout(std::time::Duration::from_secs(30));
109
110        // Create connection pool
111        let pool = SqlitePoolOptions::new()
112            .max_connections(5)
113            .connect_with(options)
114            .await
115            .map_err(|e| {
116                SecretsError::Storage(format!(
117                    "Failed to open database at {}: {e}",
118                    db_path.display()
119                ))
120            })?;
121
122        // Initialize schema
123        sqlx::query(SCHEMA)
124            .execute(&pool)
125            .await
126            .map_err(|e| SecretsError::Storage(format!("Failed to initialize schema: {e}")))?;
127
128        info!("Opened persistent secrets store at {}", db_path.display());
129
130        Ok(Self { pool, key })
131    }
132
133    /// Constructs a storage key from scope and name.
134    ///
135    /// Format: `{scope}:{name}`
136    #[inline]
137    fn make_key(scope: &str, name: &str) -> String {
138        format!("{scope}:{name}")
139    }
140
141    /// Get the current timestamp as ISO 8601 string.
142    #[allow(clippy::cast_possible_wrap)]
143    fn now_iso8601() -> String {
144        let now = std::time::SystemTime::now()
145            .duration_since(std::time::UNIX_EPOCH)
146            .unwrap_or_default()
147            .as_secs();
148        // Convert to ISO 8601 format for SQLite TEXT storage
149        chrono::DateTime::from_timestamp(now as i64, 0).map_or_else(
150            || "1970-01-01T00:00:00Z".to_string(),
151            |dt| dt.format("%Y-%m-%dT%H:%M:%SZ").to_string(),
152        )
153    }
154
155    /// Parse ISO 8601 timestamp to Unix timestamp.
156    fn parse_timestamp(s: &str) -> i64 {
157        chrono::DateTime::parse_from_rfc3339(s).map_or(0, |dt| dt.timestamp())
158    }
159}
160
161#[async_trait]
162impl SecretsProvider for PersistentSecretsStore {
163    async fn get_secret(&self, scope: &str, name: &str) -> Result<Secret> {
164        let storage_key = Self::make_key(scope, name);
165
166        let row = sqlx::query("SELECT encrypted_value FROM secrets WHERE storage_key = ?")
167            .bind(&storage_key)
168            .fetch_optional(&self.pool)
169            .await
170            .map_err(|e| SecretsError::Storage(format!("Failed to query secret: {e}")))?;
171
172        match row {
173            Some(row) => {
174                let encrypted_value: Vec<u8> = row
175                    .try_get("encrypted_value")
176                    .map_err(|e| SecretsError::Storage(format!("Failed to read value: {e}")))?;
177
178                let decrypted = self.key.decrypt(&encrypted_value)?;
179
180                let value = String::from_utf8(decrypted)
181                    .map_err(|e| SecretsError::Decryption(format!("Invalid UTF-8: {e}")))?;
182
183                debug!("Retrieved secret: {}", storage_key);
184                Ok(Secret::new(value))
185            }
186            None => Err(SecretsError::NotFound {
187                name: name.to_string(),
188            }),
189        }
190    }
191
192    async fn get_secrets(&self, scope: &str, names: &[&str]) -> Result<HashMap<String, Secret>> {
193        let mut results = HashMap::with_capacity(names.len());
194
195        for name in names {
196            // For batch retrieval, we silently skip missing secrets
197            // rather than returning an error
198            if let Ok(secret) = self.get_secret(scope, name).await {
199                results.insert((*name).to_string(), secret);
200            }
201        }
202
203        Ok(results)
204    }
205
206    async fn list_secrets(&self, scope: &str) -> Result<Vec<SecretMetadata>> {
207        let prefix = format!("{scope}:%");
208
209        let rows = sqlx::query(
210            "SELECT name, version, created_at, updated_at FROM secrets WHERE storage_key LIKE ? ORDER BY name",
211        )
212        .bind(&prefix)
213        .fetch_all(&self.pool)
214        .await
215        .map_err(|e| SecretsError::Storage(format!("Failed to list secrets: {e}")))?;
216
217        let mut results = Vec::with_capacity(rows.len());
218
219        for row in rows {
220            let name: String = row
221                .try_get("name")
222                .map_err(|e| SecretsError::Storage(format!("Failed to read name: {e}")))?;
223            let version: i64 = row
224                .try_get("version")
225                .map_err(|e| SecretsError::Storage(format!("Failed to read version: {e}")))?;
226            let created_at: String = row
227                .try_get("created_at")
228                .map_err(|e| SecretsError::Storage(format!("Failed to read created_at: {e}")))?;
229            let updated_at: String = row
230                .try_get("updated_at")
231                .map_err(|e| SecretsError::Storage(format!("Failed to read updated_at: {e}")))?;
232
233            #[allow(clippy::cast_possible_truncation, clippy::cast_sign_loss)]
234            results.push(SecretMetadata {
235                name,
236                version: version as u32,
237                created_at: Self::parse_timestamp(&created_at),
238                updated_at: Self::parse_timestamp(&updated_at),
239            });
240        }
241
242        debug!("Listed {} secrets in scope: {}", results.len(), scope);
243        Ok(results)
244    }
245
246    async fn exists(&self, scope: &str, name: &str) -> Result<bool> {
247        let storage_key = Self::make_key(scope, name);
248
249        let row = sqlx::query("SELECT 1 FROM secrets WHERE storage_key = ?")
250            .bind(&storage_key)
251            .fetch_optional(&self.pool)
252            .await
253            .map_err(|e| SecretsError::Storage(format!("Failed to check existence: {e}")))?;
254
255        Ok(row.is_some())
256    }
257}
258
259#[async_trait]
260impl SecretsStore for PersistentSecretsStore {
261    async fn set_secret(&self, scope: &str, name: &str, value: &Secret) -> Result<()> {
262        let storage_key = Self::make_key(scope, name);
263
264        // Encrypt the secret value
265        let encrypted = self.key.encrypt(value.expose().as_bytes())?;
266
267        let now = Self::now_iso8601();
268
269        // Check if secret exists to determine version
270        let existing = sqlx::query("SELECT version, created_at FROM secrets WHERE storage_key = ?")
271            .bind(&storage_key)
272            .fetch_optional(&self.pool)
273            .await
274            .map_err(|e| SecretsError::Storage(format!("Failed to check existing: {e}")))?;
275
276        if let Some(row) = existing {
277            // Update existing secret
278            let version: i64 = row.try_get("version").unwrap_or(1);
279            let new_version = version + 1;
280
281            sqlx::query(
282                "UPDATE secrets SET encrypted_value = ?, version = ?, updated_at = ? WHERE storage_key = ?",
283            )
284            .bind(&encrypted)
285            .bind(new_version)
286            .bind(&now)
287            .bind(&storage_key)
288            .execute(&self.pool)
289            .await
290            .map_err(|e| SecretsError::Storage(format!("Failed to update secret: {e}")))?;
291
292            debug!("Updated secret: {} (version {})", storage_key, new_version);
293        } else {
294            // Insert new secret
295            sqlx::query(
296                "INSERT INTO secrets (storage_key, encrypted_value, name, version, created_at, updated_at) VALUES (?, ?, ?, 1, ?, ?)",
297            )
298            .bind(&storage_key)
299            .bind(&encrypted)
300            .bind(name)
301            .bind(&now)
302            .bind(&now)
303            .execute(&self.pool)
304            .await
305            .map_err(|e| SecretsError::Storage(format!("Failed to insert secret: {e}")))?;
306
307            debug!("Stored secret: {} (version 1)", storage_key);
308        }
309
310        Ok(())
311    }
312
313    async fn delete_secret(&self, scope: &str, name: &str) -> Result<()> {
314        let storage_key = Self::make_key(scope, name);
315
316        let result = sqlx::query("DELETE FROM secrets WHERE storage_key = ?")
317            .bind(&storage_key)
318            .execute(&self.pool)
319            .await
320            .map_err(|e| SecretsError::Storage(format!("Failed to delete secret: {e}")))?;
321
322        if result.rows_affected() == 0 {
323            return Err(SecretsError::NotFound {
324                name: name.to_string(),
325            });
326        }
327
328        debug!("Deleted secret: {}", storage_key);
329        Ok(())
330    }
331}
332
333#[cfg(test)]
334mod tests {
335    use super::*;
336
337    async fn create_test_store() -> (PersistentSecretsStore, tempfile::TempDir) {
338        let temp_dir = tempfile::tempdir().unwrap();
339        let db_path = temp_dir.path().join("test_secrets.sqlite");
340        let key = EncryptionKey::generate();
341        let store = PersistentSecretsStore::open(&db_path, key).await.unwrap();
342        (store, temp_dir)
343    }
344
345    #[tokio::test]
346    async fn test_set_and_get_secret() {
347        let (store, _temp) = create_test_store().await;
348
349        let secret = Secret::new("super-secret-value");
350        store
351            .set_secret("deployment/myapp", "db-password", &secret)
352            .await
353            .unwrap();
354
355        let retrieved = store
356            .get_secret("deployment/myapp", "db-password")
357            .await
358            .unwrap();
359        assert_eq!(retrieved.expose(), "super-secret-value");
360    }
361
362    #[tokio::test]
363    async fn test_get_nonexistent_secret() {
364        let (store, _temp) = create_test_store().await;
365
366        let result = store.get_secret("deployment/myapp", "nonexistent").await;
367        assert!(matches!(result, Err(SecretsError::NotFound { .. })));
368    }
369
370    #[tokio::test]
371    async fn test_exists() {
372        let (store, _temp) = create_test_store().await;
373
374        assert!(!store.exists("scope", "name").await.unwrap());
375
376        let secret = Secret::new("value");
377        store.set_secret("scope", "name", &secret).await.unwrap();
378
379        assert!(store.exists("scope", "name").await.unwrap());
380    }
381
382    #[tokio::test]
383    async fn test_delete_secret() {
384        let (store, _temp) = create_test_store().await;
385
386        let secret = Secret::new("to-be-deleted");
387        store
388            .set_secret("scope", "deleteme", &secret)
389            .await
390            .unwrap();
391        assert!(store.exists("scope", "deleteme").await.unwrap());
392
393        store.delete_secret("scope", "deleteme").await.unwrap();
394        assert!(!store.exists("scope", "deleteme").await.unwrap());
395    }
396
397    #[tokio::test]
398    async fn test_delete_nonexistent() {
399        let (store, _temp) = create_test_store().await;
400
401        let result = store.delete_secret("scope", "nonexistent").await;
402        assert!(matches!(result, Err(SecretsError::NotFound { .. })));
403    }
404
405    #[tokio::test]
406    async fn test_list_secrets() {
407        let (store, _temp) = create_test_store().await;
408
409        // Add secrets to different scopes
410        store
411            .set_secret("scope1", "secret-a", &Secret::new("a"))
412            .await
413            .unwrap();
414        store
415            .set_secret("scope1", "secret-b", &Secret::new("b"))
416            .await
417            .unwrap();
418        store
419            .set_secret("scope2", "secret-c", &Secret::new("c"))
420            .await
421            .unwrap();
422
423        // List scope1 - should only see 2 secrets
424        let list = store.list_secrets("scope1").await.unwrap();
425        assert_eq!(list.len(), 2);
426        assert_eq!(list[0].name, "secret-a");
427        assert_eq!(list[1].name, "secret-b");
428
429        // List scope2 - should only see 1 secret
430        let list = store.list_secrets("scope2").await.unwrap();
431        assert_eq!(list.len(), 1);
432        assert_eq!(list[0].name, "secret-c");
433    }
434
435    #[tokio::test]
436    async fn test_get_secrets_batch() {
437        let (store, _temp) = create_test_store().await;
438
439        store
440            .set_secret("scope", "a", &Secret::new("value-a"))
441            .await
442            .unwrap();
443        store
444            .set_secret("scope", "b", &Secret::new("value-b"))
445            .await
446            .unwrap();
447        store
448            .set_secret("scope", "c", &Secret::new("value-c"))
449            .await
450            .unwrap();
451
452        let results = store
453            .get_secrets("scope", &["a", "c", "nonexistent"])
454            .await
455            .unwrap();
456        assert_eq!(results.len(), 2);
457
458        assert_eq!(results.get("a").unwrap().expose(), "value-a");
459        assert_eq!(results.get("c").unwrap().expose(), "value-c");
460        assert!(!results.contains_key("nonexistent"));
461    }
462
463    #[tokio::test]
464    async fn test_update_increments_version() {
465        let (store, _temp) = create_test_store().await;
466
467        store
468            .set_secret("scope", "versioned", &Secret::new("v1"))
469            .await
470            .unwrap();
471
472        let list = store.list_secrets("scope").await.unwrap();
473        assert_eq!(list[0].version, 1);
474
475        store
476            .set_secret("scope", "versioned", &Secret::new("v2"))
477            .await
478            .unwrap();
479
480        let list = store.list_secrets("scope").await.unwrap();
481        assert_eq!(list[0].version, 2);
482    }
483
484    #[tokio::test]
485    async fn test_persistence() {
486        let temp_dir = tempfile::tempdir().unwrap();
487        let db_path = temp_dir.path().join("persist_test.sqlite");
488
489        // Use fixed key for persistence test
490        let key_bytes = [42u8; 32];
491        let key = EncryptionKey::from_bytes(&key_bytes).unwrap();
492
493        // Write data
494        {
495            let store = PersistentSecretsStore::open(&db_path, key.clone())
496                .await
497                .unwrap();
498            store
499                .set_secret("scope", "persistent", &Secret::new("persistent-value"))
500                .await
501                .unwrap();
502        }
503
504        // Reopen and verify
505        {
506            let store = PersistentSecretsStore::open(&db_path, key).await.unwrap();
507            let secret = store.get_secret("scope", "persistent").await.unwrap();
508            assert_eq!(secret.expose(), "persistent-value");
509        }
510    }
511
512    #[tokio::test]
513    async fn test_wrong_key_fails_decryption() {
514        let temp_dir = tempfile::tempdir().unwrap();
515        let db_path = temp_dir.path().join("wrong_key_test.sqlite");
516
517        // Write with one key
518        let key1 = EncryptionKey::generate();
519        {
520            let store = PersistentSecretsStore::open(&db_path, key1).await.unwrap();
521            store
522                .set_secret("scope", "secret", &Secret::new("value"))
523                .await
524                .unwrap();
525        }
526
527        // Try to read with different key
528        let key2 = EncryptionKey::generate();
529        {
530            let store = PersistentSecretsStore::open(&db_path, key2).await.unwrap();
531            let result = store.get_secret("scope", "secret").await;
532            assert!(result.is_err()); // Should fail decryption
533        }
534    }
535
536    #[tokio::test]
537    async fn test_open_with_directory() {
538        let temp_dir = tempfile::tempdir().unwrap();
539        let key = EncryptionKey::generate();
540
541        // Pass directory path instead of file path
542        let store = PersistentSecretsStore::open(temp_dir.path(), key)
543            .await
544            .unwrap();
545
546        store
547            .set_secret("scope", "test", &Secret::new("value"))
548            .await
549            .unwrap();
550
551        // Verify database file was created
552        let expected_path = temp_dir.path().join(DEFAULT_DB_FILENAME);
553        assert!(expected_path.exists());
554    }
555
556    #[test]
557    fn test_make_key() {
558        assert_eq!(
559            PersistentSecretsStore::make_key("scope", "name"),
560            "scope:name"
561        );
562        assert_eq!(
563            PersistentSecretsStore::make_key("deployment/app", "secret"),
564            "deployment/app:secret"
565        );
566    }
567
568    #[tokio::test]
569    async fn test_empty_secret() {
570        let (store, _temp) = create_test_store().await;
571
572        let secret = Secret::new("");
573        store.set_secret("scope", "empty", &secret).await.unwrap();
574
575        let retrieved = store.get_secret("scope", "empty").await.unwrap();
576        assert_eq!(retrieved.expose(), "");
577    }
578
579    #[tokio::test]
580    async fn test_unicode_secret() {
581        let (store, _temp) = create_test_store().await;
582
583        let secret = Secret::new("hello world");
584        store.set_secret("scope", "unicode", &secret).await.unwrap();
585
586        let retrieved = store.get_secret("scope", "unicode").await.unwrap();
587        assert_eq!(retrieved.expose(), "hello world");
588    }
589
590    #[tokio::test]
591    async fn test_large_secret() {
592        let (store, _temp) = create_test_store().await;
593
594        // 1MB secret
595        let large_value: String = "x".repeat(1024 * 1024);
596        let secret = Secret::new(&large_value);
597        store.set_secret("scope", "large", &secret).await.unwrap();
598
599        let retrieved = store.get_secret("scope", "large").await.unwrap();
600        assert_eq!(retrieved.expose().len(), 1024 * 1024);
601    }
602}