Add rofl-containers generic ROFL app runtime for containers

Cargo.toml

@@ -17,6 +17,7 @@ members = [
 
     # ROFL.
     "rofl-utils",
+    "rofl-containers",
 
     # Test runtimes.
     "tests/runtimes/benchmarking",

rofl-containers/Cargo.toml

@@ -0,0 +1,11 @@
+[package]
+name = "rofl-containers"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+# Oasis SDK.
+oasis-runtime-sdk = { path = "../runtime-sdk", features = ["tdx"] }
+
+# Third party.
+base64 = "0.22.1"

rofl-containers/src/main.rs

@@ -0,0 +1,40 @@
+use std::env;
+
+use base64::prelude::*;
+use oasis_runtime_sdk::{cbor, modules::rofl::app::prelude::*};
+
+/// A generic container-based ROFL application.
+struct ContainersApp;
+
+#[async_trait]
+impl App for ContainersApp {
+    const VERSION: Version = sdk::version_from_cargo!();
+
+    fn id() -> AppId {
+        // Fetch application ID from the ROFL_APP_ID environment variable.
+        // This would usually be passed via the kernel cmdline.
+        AppId::from_bech32(&env::var("ROFL_APP_ID").expect("Must configure ROFL_APP_ID."))
+            .expect("Corrupted ROFL_APP_ID (must be Bech32-encoded ROFL app ID).")
+    }
+
+    fn consensus_trust_root() -> Option<TrustRoot> {
+        // Fetch consensus trust root from the ROFL_CONSENSUS_TRUST_ROOT environment variable.
+        // This would usually be passed via the kernel cmdline.
+        let raw_trust_root = env::var("ROFL_CONSENSUS_TRUST_ROOT")
+            .expect("Must configure ROFL_CONSENSUS_TRUST_ROOT.");
+        cbor::from_slice(
+            &BASE64_STANDARD
+                .decode(raw_trust_root)
+                .expect("Corrupted ROFL_CONSENSUS_TRUST_ROOT (must be Base64-encoded CBOR)."),
+        )
+        .expect("Corrupted ROFL_CONSENSUS_TRUST_ROOT (must be Base64-encoded CBOR).")
+    }
+
+    async fn run(self: Arc<Self>, _env: Environment<Self>) {
+        // TODO: Start the REST API server.
+    }
+}
+
+fn main() {
+    ContainersApp.start();
+}

runtime-sdk/src/modules/rofl/app/mod.rs

@@ -3,6 +3,7 @@ use std::sync::Arc;
 
 use anyhow::Result;
 use async_trait::async_trait;
+use base64::prelude::*;
 use tokio::sync::mpsc;
 
 use crate::{
@@ -38,11 +39,28 @@ pub trait App: Send + Sync + 'static {
     const VERSION: version::Version;
 
     /// Identifier of the application (used for registrations).
-    fn id() -> AppId;
+    fn id() -> AppId {
+        // By default we fetch the application identifier from the build-time environment.
+        AppId::from_bech32(
+            option_env!("ROFL_APP_ID").expect("Override App::id or specify ROFL_APP_ID."),
+        )
+        .expect("Corrupted ROFL_APP_ID (must be Bech32-encoded ROFL app ID).")
+    }
 
     /// Return the consensus layer trust root for this runtime; if `None`, consensus layer integrity
     /// verification will not be performed.
-    fn consensus_trust_root() -> Option<TrustRoot>;
+    fn consensus_trust_root() -> Option<TrustRoot> {
+        // By default we fetch the trust root from the build-time environment.
+        option_env!("ROFL_CONSENSUS_TRUST_ROOT").map(|raw_trust_root| {
+            // Parse from base64-encoded CBOR.
+            cbor::from_slice(
+                &BASE64_STANDARD
+                    .decode(raw_trust_root)
+                    .expect("Corrupted ROFL_CONSENSUS_TRUST_ROOT (must be Base64-encoded CBOR)."),
+            )
+            .expect("Corrupted ROFL_CONSENSUS_TRUST_ROOT (must be Base64-encoded CBOR).")
+        })
+    }
 
     /// Create a new unsigned transaction.
     fn new_transaction<B>(&self, method: &str, body: B) -> transaction::Transaction