Merge pull request #213 from enigmampc/compute_update_state

updating state during computations

Author: AvishaiW

.drone.yml

@@ -12,6 +12,7 @@ steps:
     commands:
       - LD_LIBRARY_PATH=/opt/intel/libsgx-enclave-common/aesm /opt/intel/libsgx-enclave-common/aesm/aesm_service
       - . /opt/sgxsdk/environment && . /root/.cargo/env
+      - cargo --version
       - cd enigma-core && RUSTFLAGS=-Awarnings make DEBUG=1
       - cd app && RUSTFLAGS=-Awarnings cargo test
     volumes:

enigma-core/app/src/db/dal.rs

@@ -15,6 +15,8 @@ pub struct DB {
     // the DB needs to store the options for creating new
     // cf's that would be able to imitate the DB behaviour
     pub options: Options,
+    // keeps track if the state needs to be rebuilt
+    state_updated: bool,
 }
 
 impl DB {
@@ -53,9 +55,23 @@ impl DB {
         let cf_list_burrowed = cf_list.iter().map(String::as_str).collect::<Vec<&str>>();
         let database = rocks_db::open_cf(&options, &location, &cf_list_burrowed[..])?;
         let location = location.as_ref().to_path_buf();
-        let db_par = DB { location, database, options };
+        // the state_updated is initialized to true since it won't be necessary to build
+        // the state when the DB is empty.
+        let db_par = DB { location, database, options, state_updated: true};
         Ok(db_par)
     }
+
+    /// updates the state_updated field according to the status of the state.
+    /// every time the state is built (=true) and
+    /// on the other hand when new deltas enter the DB (=false).
+    pub fn update_state_status(&mut self, state: bool) {
+        self.state_updated = state;
+    }
+
+    /// get the current status of the state
+    pub fn get_state_status(& mut self) -> bool {
+        self.state_updated
+    }
 }
 
 pub trait CRUDInterface<E, K, T, V> {

enigma-core/app/src/networking/ipc_listener.rs

@@ -250,6 +250,8 @@ pub(self) mod handling {
         if results.into_iter().any(| result | result.is_err()) {
             status = FAILED;
         }
+        // since a new delta and bytecode were added, the state is no longer updated
+        db.update_state_status(false);
         let result = IpcResults::Status(status);
         Ok(IpcResponse::UpdateNewContractOnDeployment { address, result })
     }
@@ -281,6 +283,8 @@ pub(self) mod handling {
             let delta = IpcStatusResult { address, key, status };
             errors.push(delta);
         }
+        // since a new delta was added the state is no longer updated
+        db.update_state_status(false);
         let result = IpcResults::UpdateDeltasResult { status: overall_status, errors };
         Ok(IpcResponse::UpdateDeltas {result})
     }
@@ -314,6 +318,7 @@ pub(self) mod handling {
         let msg = response.response.from_hex()?;
         km_u::ptt_res(eid, &msg)?;
         let res = km_u::ptt_build_state(db, eid)?;
+        db.update_state_status(true);
         let result: Vec<_> = res
             .into_iter()
             .map(|a| IpcStatusResult{ address: a.to_hex(), status: FAILED, key: None })
@@ -366,6 +371,10 @@ pub(self) mod handling {
         let mut user_pubkey = [0u8; 64];
         user_pubkey.clone_from_slice(&input.user_dhkey.from_hex()?);
 
+        if !db.get_state_status() {
+            let res = km_u::ptt_build_state(db, eid)?;
+            db.update_state_status(true);
+        }
         let bytecode = db.get_contract(address)?;
 
 

enigma-core/enclave/src/km_t/principal.rs

@@ -58,7 +58,7 @@ pub(crate) fn ecall_build_state_internal(db_ptr: *const RawPointer) -> Result<Ve
 
     'contract: for (addrs, key) in guard.iter() {
         // Get the state and decrypt it.
-        // if no state exist create new one and if failed decrypting push to failed_contracts and move on.
+        // if no state exists create a new one and if failed decrypting, push to failed_contracts and move on.
         let (mut start, mut state ) = match runtime_ocalls_t::get_state(db_ptr, *addrs) {
             Ok(enc_state) => match ContractState::decrypt(enc_state, &key) {
                 Ok(state) => (state.delta_index+1, state),