Fix (sealing): Simple sealing with random nonce

migrations/20250326160659_sealing.sql

@@ -3,5 +3,6 @@
 CREATE TABLE root_key (
 	version INTEGER PRIMARY KEY CHECK ( version = 1 ),
 	encrypted_key BLOB NOT NULL,
+	nonce BLOB,
 	type TEXT NOT NULL CHECK ( type IN ('dev_only', 'simple') )
 );

src/engines/kv/data.rs

@@ -1,8 +1,12 @@
 use super::structs::KvV2WriteRequest;
 use crate::{
-    common::HttpError, engines::{
-        kv::structs::{KvSecretData, KvSecretRes, KvV2WriteResponse, Wrapper}, EnginePath
-    }, storage::sealing::{encrypt, decrypt}, DbPool
+    DbPool,
+    common::HttpError,
+    engines::{
+        EnginePath,
+        kv::structs::{KvSecretData, KvSecretRes, KvV2WriteResponse, Wrapper},
+    },
+    storage::sealing::{decrypt, encrypt},
 };
 use axum::{
     Extension, Json,
@@ -52,9 +56,7 @@ pub async fn get_data(
     Path(path): Path<String>,
     Extension(EnginePath(engine_path)): Extension<EnginePath>,
 ) -> Result<Response, ()> {
-    debug!(
-        "Get request: Engine: {engine_path}, path: {path}",
-    );
+    debug!("Get request: Engine: {engine_path}, path: {path}",);
 
     let res = if params.version != 0 {
         // With specific version
@@ -138,7 +140,8 @@ pub async fn post_data(
         "src/engines/kv/post_secret.sql",
         engine_path,
         kv_path,
-        nonce, enc,
+        nonce,
+        enc,
         ts,
         secret.version,
     )
@@ -230,8 +233,6 @@ pub async fn delete_data(
     Ok(NoContent.into_response())
 }
 
-
-// Not 
 pub async fn patch_data(
     State(pool): State<DbPool>,
     Path(kv_path): Path<String>,
@@ -241,4 +242,3 @@ pub async fn patch_data(
     // TODO: implement only application/merge-patch+json
     todo!("Not implemented")
 }
-

src/storage/sealing.rs

@@ -13,8 +13,8 @@ use super::DbPool;
 enum KeyEnum {
     /// Final key
     MainKey(Vec<u8>),
-    /// Encrypted with single secret
-    Simple(Vec<u8>),
+    /// Encrypted with single secret (protected_rk, nonce)
+    Simple(Vec<u8>, Vec<u8>),
     /// Unknown or not initialized
     Uninitialized,
     // ShamirPortion(Vec<String>),
@@ -25,6 +25,7 @@ static ROOT_KEY_MAYBE: RwLock<KeyEnum> = RwLock::const_new(KeyEnum::Uninitialize
 struct ProtectedRK {
     pub protection_type: String,
     pub encrypted_key: Vec<u8>,
+    pub nonce: Option<Vec<u8>>,
 }
 
 /// Returns `true` if vault is initialized or unsealed.
@@ -41,7 +42,7 @@ pub async fn prepare_unseal(pool: &DbPool) -> bool {
 
     let rk = sqlx::query_as!(
         ProtectedRK,
-        "SELECT encrypted_key, type as protection_type FROM root_key ORDER BY version LIMIT 1"
+        "SELECT encrypted_key, type as protection_type, nonce FROM root_key ORDER BY version LIMIT 1"
     )
     .fetch_optional(pool)
     .await
@@ -69,7 +70,10 @@ pub async fn prepare_unseal(pool: &DbPool) -> bool {
             *lock = KeyEnum::MainKey(v.encrypted_key);
         }
         "simple" => {
-            *lock = KeyEnum::Simple(v.encrypted_key);
+            *lock = KeyEnum::Simple(
+                v.encrypted_key,
+                v.nonce.expect("Simple encryption but the nonce is missing"),
+            );
         }
         _ => panic!("Unknown root key type in database"),
     }
@@ -79,6 +83,7 @@ pub async fn prepare_unseal(pool: &DbPool) -> bool {
 /// Must NOT be used in production.
 /// Token is plainly stored in the database and will be unsealed directly by [prepare_unseal]!
 /// Danger!
+#[allow(unused)]
 pub async fn init_insecure_in_db(pool: &DbPool) {
     let root_key = Aes256GcmSiv::generate_key(&mut OsRng);
     let root_key = root_key.as_slice().to_owned();
@@ -86,17 +91,23 @@ pub async fn init_insecure_in_db(pool: &DbPool) {
     warn!(
         "Danger: INSECURE! Generated root key is stored plainly in the database. Must ONLY be used for development!"
     );
-    write_new_root_key(pool, root_key, "dev_only").await;
+    write_new_root_key(pool, root_key, "dev_only", None).await;
 }
 
-async fn write_new_root_key(pool: &DbPool, protected_key: Vec<u8>, type_to_be: &str) {
+async fn write_new_root_key(
+    pool: &DbPool,
+    protected_key: Vec<u8>,
+    type_to_be: &str,
+    nonce: Option<&[u8]>,
+) {
     let _ = sqlx::query!(
         "
-        INSERT INTO root_key (encrypted_key, type, version)
-        VALUES ($1, $2, 1)
+        INSERT INTO root_key (encrypted_key, type, version, nonce)
+        VALUES ($1, $2, 1, $3)
         ",
         protected_key,
-        type_to_be
+        type_to_be,
+        nonce
     )
     .execute(pool)
     .await
@@ -117,7 +128,7 @@ pub async fn sealing_status() {
     let lock = ROOT_KEY_MAYBE.read().await;
     match &*lock {
         KeyEnum::MainKey(_) => todo!(),
-        KeyEnum::Simple(_) => todo!(),
+        KeyEnum::Simple(_, _) => todo!(),
         KeyEnum::Uninitialized => todo!(),
     }
 }
@@ -130,8 +141,8 @@ pub async fn provide_key(key: String) {
                 info!("Providing keys is useless since vault is already unlocked");
                 return;
             }
-            KeyEnum::Simple(protected_rk) => {
-                KeyEnum::MainKey(simple::unseal(protected_rk, key).await)
+            KeyEnum::Simple(protected_rk, nonce) => {
+                KeyEnum::MainKey(simple::unseal(protected_rk, key, nonce).await)
             }
             KeyEnum::Uninitialized => {
                 error!("Cannot process provided key when the vault is uninitialized");

src/storage/sealing/simple.rs

@@ -1,31 +1,36 @@
-use aes_gcm_siv::{aead::{Aead, OsRng}, Aes256GcmSiv, KeyInit};
-use base64::{prelude::BASE64_STANDARD, Engine};
+use aes_gcm_siv::{
+    AeadCore, Aes256GcmSiv, KeyInit,
+    aead::{Aead, OsRng, generic_array::GenericArray},
+};
+use base64::{Engine, prelude::BASE64_STANDARD};
 
 use crate::DbPool;
 
 use super::write_new_root_key;
 
 pub async fn init_simple(pool: &DbPool) -> String {
-    // let root_key = write_new_root_key(pool, p_type).await;
     let root_key = Aes256GcmSiv::generate_key(&mut OsRng);
+    let nonce: GenericArray<u8, <Aes256GcmSiv as AeadCore>::NonceSize> =
+        Aes256GcmSiv::generate_nonce(&mut OsRng); // 96-bits; unique per message
     let root_key = root_key.as_slice().to_owned();
 
     let (user_key, protected_rk) = {
         let key = Aes256GcmSiv::generate_key(&mut OsRng);
         let cipher = Aes256GcmSiv::new(&key);
-        let nonce: &[u8; 12] = b"hello world!"; // TODO
+        let nonce: &[u8] = nonce.as_slice();
+        debug_assert_eq!(nonce.len(), 12);
         let nonce = aes_gcm_siv::aead::generic_array::GenericArray::from_slice(nonce);
         let enc = cipher.encrypt(nonce, root_key.as_slice()).unwrap();
         (key, enc)
     };
-    write_new_root_key(pool, protected_rk, "simple").await;
+    write_new_root_key(pool, protected_rk, "simple", Some(nonce.as_slice())).await;
     BASE64_STANDARD.encode(user_key)
 }
 
-pub async fn unseal(protected_rk: &Vec<u8>, key: String) -> Vec<u8> {
+pub async fn unseal(protected_rk: &Vec<u8>, key: String, nonce: &[u8]) -> Vec<u8> {
     let key = BASE64_STANDARD.decode(key).unwrap();
     let cipher = Aes256GcmSiv::new_from_slice(&key).unwrap();
-    let nonce: &[u8; 12] = b"hello world!"; // TODO
+    debug_assert_eq!(nonce.len(), 12);
     let nonce = aes_gcm_siv::aead::generic_array::GenericArray::from_slice(nonce);
     cipher.decrypt(nonce, protected_rk.as_ref()).unwrap()
 }