feat(L2): basic sequencer (lambdaclass#586)

> [!WARNING]
> This PR depends on lambdaclass#575 and must be merged after it.

**Motivation**

<!-- Why does this pull request exist? What are its goals? -->

**Description**

<!-- A clear and concise general description of the changes this PR
introduces -->

- Adds block producer module
- Implements `Engine` to advance the blockchain

---------

Co-authored-by: fmoletta <fedemoletta@hotmail.com>
Co-authored-by: Manuel Bilbao <manuel.bilbao@lambdaclass.com>
Co-authored-by: Manuel Iñaki Bilbao <bilbaomanuel98@gmail.com>

Cargo.toml

@@ -49,4 +49,5 @@ crc32fast = "1.4.2"
 lazy_static = "1.5.0"
 sha3 = "0.10.8"
 tokio-util = { version = "0.7.12", features = ["rt"] }
+jsonwebtoken = "9.3.0"
 rand = "0.8.5"

cmd/ethereum_rust/ethereum_rust.rs

@@ -116,15 +116,18 @@ async fn main() {
         let size = blocks.len();
         for block in blocks {
             let hash = block.header.compute_block_hash();
-            info!("Adding block {} with hash {}.", block.header.number, hash);
+            info!(
+                "Adding block {} with hash {:#x}.",
+                block.header.number, hash
+            );
             match add_block(&block, &store) {
                 Ok(()) => store
                     .set_canonical_block(block.header.number, hash)
                     .unwrap(),
-                _ => {
+                Err(error) => {
                     warn!(
-                        "Failed to add block {} with hash {}.",
-                        block.header.number, hash
+                        "Failed to add block {} with hash {:#x}: {}",
+                        block.header.number, hash, error
                     );
                 }
             }
@@ -159,7 +162,7 @@ async fn main() {
     // We do not want to start the networking module if the l2 feature is enabled.
     cfg_if::cfg_if! {
         if #[cfg(feature = "l2")] {
-            let l2_operator = ethereum_rust_l2::start_operator().into_future();
+            let l2_operator = ethereum_rust_l2::start_operator(store.clone()).into_future();
             tracker.spawn(l2_operator);
             let l2_prover = ethereum_rust_l2::start_prover().into_future();
             tracker.spawn(l2_prover);

crates/common/serde_utils.rs

@@ -290,6 +290,28 @@ pub mod bytes48 {
         {
             serialize_vec_of_hex_encodables(value, serializer)
         }
+
+        pub fn deserialize<'de, D>(d: D) -> Result<Vec<[u8; 48]>, D::Error>
+        where
+            D: Deserializer<'de>,
+        {
+            let value = Vec::<String>::deserialize(d)?;
+            let mut output = Vec::new();
+            for str in value {
+                let bytes = hex::decode(str.trim_start_matches("0x"))
+                    .map_err(|e| D::Error::custom(e.to_string()))?;
+                if bytes.len() != 48 {
+                    return Err(D::Error::custom(format!(
+                        "Expected 48 bytes, got {}",
+                        bytes.len()
+                    )));
+                }
+                let mut blob = [0u8; 48];
+                blob.copy_from_slice(&bytes);
+                output.push(blob);
+            }
+            Ok(output)
+        }
     }
 }
 
@@ -310,6 +332,29 @@ pub mod blob {
         {
             serialize_vec_of_hex_encodables(value, serializer)
         }
+
+        pub fn deserialize<'de, D>(deserializer: D) -> Result<Vec<[u8; BYTES_PER_BLOB]>, D::Error>
+        where
+            D: Deserializer<'de>,
+        {
+            let value = Vec::<String>::deserialize(deserializer)?;
+            let mut output = Vec::new();
+            for str in value {
+                let bytes = hex::decode(str.trim_start_matches("0x"))
+                    .map_err(|e| D::Error::custom(e.to_string()))?;
+                if bytes.len() != BYTES_PER_BLOB {
+                    return Err(D::Error::custom(format!(
+                        "Expected {} bytes, got {}",
+                        BYTES_PER_BLOB,
+                        bytes.len()
+                    )));
+                }
+                let mut blob = [0u8; BYTES_PER_BLOB];
+                blob.copy_from_slice(&bytes);
+                output.push(blob);
+            }
+            Ok(output)
+        }
     }
 }
 

crates/common/types/blobs_bundle.rs

@@ -5,7 +5,7 @@ use ethereum_rust_rlp::{
     error::RLPDecodeError,
     structs::{Decoder, Encoder},
 };
-use serde::Serialize;
+use serde::{Deserialize, Serialize};
 
 use super::BYTES_PER_BLOB;
 
@@ -14,7 +14,7 @@ pub type Blob = [u8; BYTES_PER_BLOB];
 pub type Commitment = Bytes48;
 pub type Proof = Bytes48;
 
-#[derive(Clone, Debug, PartialEq, Eq, Serialize)]
+#[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize)]
 #[serde(rename_all = "camelCase")]
 /// Struct containing all the blobs for a blob transaction, along with the corresponding commitments and proofs
 pub struct BlobsBundle {

crates/l2/Cargo.toml

@@ -12,16 +12,18 @@ tokio-util.workspace = true
 tracing.workspace = true
 serde.workspace = true
 serde_json.workspace = true
-sp1-sdk = "2.0.0"
 ethereum-types.workspace = true
 ethereum_rust-core.workspace = true
 ethereum_rust-rlp.workspace = true
 ethereum_rust-rpc.workspace = true
 ethereum_rust-blockchain.workspace = true
-libsecp256k1 = "0.7.1"
+ethereum_rust-storage.workspace = true
+hex.workspace = true
 bytes.workspace = true
+jsonwebtoken.workspace = true
+sp1-sdk = "2.0.0"
+libsecp256k1 = "0.7.1"
 keccak-hash = "0.10.0"
-hex.workspace = true
 
 [lib]
 path = "./l2.rs"

crates/l2/operator/block_producer.rs

@@ -1,3 +1,48 @@
-pub struct BlockProducer;
+use crate::operator::engine::Engine;
+use ethereum_rust_rpc::types::fork_choice::{ForkChoiceState, PayloadAttributesV3};
+use ethereum_types::H256;
+use std::time::{Duration, SystemTime, UNIX_EPOCH};
+use tokio::time::sleep;
 
-pub async fn start_block_producer() {}
+pub async fn start_block_producer(current_block_hash: H256) {
+    let mut current_block_hash = current_block_hash;
+    loop {
+        let secret = std::fs::read("../../../jwt.hex").unwrap();
+        let engine = Engine::new("http://localhost:8551", secret.into());
+
+        let fork_choice_state = ForkChoiceState {
+            head_block_hash: current_block_hash,
+            safe_block_hash: current_block_hash,
+            finalized_block_hash: current_block_hash,
+        };
+        let payload_attributes = PayloadAttributesV3 {
+            timestamp: SystemTime::now()
+                .duration_since(UNIX_EPOCH)
+                .unwrap()
+                .as_secs(),
+            ..Default::default()
+        };
+
+        let fork_choice_response = engine
+            .engine_forkchoice_updated_v3(fork_choice_state, payload_attributes)
+            .await
+            .unwrap();
+
+        let payload_id = fork_choice_response.payload_id.unwrap();
+
+        let execution_payload_response = engine.engine_get_payload_v3(payload_id).await.unwrap();
+
+        let payload_status = engine
+            .engine_new_payload_v3(
+                execution_payload_response.execution_payload,
+                Default::default(),
+                Default::default(),
+            )
+            .await
+            .unwrap();
+
+        current_block_hash = payload_status.latest_valid_hash.unwrap();
+
+        sleep(Duration::from_secs(5)).await;
+    }
+}

crates/l2/operator/engine.rs

@@ -0,0 +1,145 @@
+use bytes::Bytes;
+use ethereum_rust_rpc::{
+    engine::{
+        fork_choice::ForkChoiceUpdatedV3,
+        payload::{GetPayloadV3Request, NewPayloadV3Request},
+        ExchangeCapabilitiesRequest,
+    },
+    types::{
+        fork_choice::{ForkChoiceResponse, ForkChoiceState, PayloadAttributesV3},
+        payload::{ExecutionPayloadResponse, ExecutionPayloadV3, PayloadStatus},
+    },
+    utils::{RpcErrorResponse, RpcRequest, RpcSuccessResponse},
+};
+use ethereum_types::H256;
+use reqwest::Client;
+use serde::Deserialize;
+use serde_json::json;
+use std::time::{SystemTime, UNIX_EPOCH};
+
+#[derive(Deserialize)]
+#[serde(untagged)]
+pub enum RpcResponse {
+    Success(RpcSuccessResponse),
+    Error(RpcErrorResponse),
+}
+
+pub struct Engine {
+    client: Client,
+    secret: Bytes,
+    execution_client_url: String,
+}
+
+impl Engine {
+    pub fn new(execution_client_url: &str, secret: Bytes) -> Self {
+        Self {
+            client: Client::new(),
+            secret,
+            execution_client_url: execution_client_url.to_string(),
+        }
+    }
+
+    async fn send_request(&self, request: RpcRequest) -> Result<RpcResponse, reqwest::Error> {
+        self.client
+            .post(&self.execution_client_url)
+            .bearer_auth(self.auth_token())
+            .header("content-type", "application/json")
+            .body(serde_json::ser::to_string(&request).unwrap())
+            .send()
+            .await?
+            .json::<RpcResponse>()
+            .await
+    }
+
+    pub async fn engine_exchange_capabilities(&self) -> Result<Vec<String>, String> {
+        let request = ExchangeCapabilitiesRequest::from(Self::capabilities()).into();
+
+        match self.send_request(request).await {
+            Ok(RpcResponse::Success(result)) => Ok(serde_json::from_value(result.result).unwrap()),
+            Ok(RpcResponse::Error(e)) => Err(e.error.message),
+            Err(e) => Err(e.to_string()),
+        }
+    }
+
+    pub async fn engine_forkchoice_updated_v3(
+        &self,
+        state: ForkChoiceState,
+        payload_attributes: PayloadAttributesV3,
+    ) -> Result<ForkChoiceResponse, String> {
+        let request = ForkChoiceUpdatedV3 {
+            fork_choice_state: state,
+            payload_attributes: Some(payload_attributes),
+        }
+        .into();
+
+        match self.send_request(request).await {
+            Ok(RpcResponse::Success(s)) => match serde_json::from_value(s.result.clone()) {
+                Ok(parsed_value) => Ok(parsed_value),
+                Err(error) => {
+                    dbg!(s.result);
+                    Err(error.to_string())
+                }
+            },
+            Ok(RpcResponse::Error(e)) => Err(e.error.message),
+            Err(e) => Err(e.to_string()),
+        }
+    }
+
+    pub async fn engine_get_payload_v3(
+        &self,
+        payload_id: u64,
+    ) -> Result<ExecutionPayloadResponse, String> {
+        let request = GetPayloadV3Request { payload_id }.into();
+
+        match self.send_request(request).await {
+            Ok(RpcResponse::Success(s)) => Ok(serde_json::from_value(s.result).unwrap()),
+            Ok(RpcResponse::Error(e)) => Err(e.error.message),
+            Err(e) => Err(e.to_string()),
+        }
+    }
+
+    pub async fn engine_new_payload_v3(
+        &self,
+        execution_payload: ExecutionPayloadV3,
+        expected_blob_versioned_hashes: Vec<H256>,
+        parent_beacon_block_root: H256,
+    ) -> Result<PayloadStatus, String> {
+        let request = NewPayloadV3Request {
+            payload: execution_payload,
+            expected_blob_versioned_hashes,
+            parent_beacon_block_root,
+        }
+        .into();
+
+        match self.send_request(request).await {
+            Ok(RpcResponse::Success(s)) => Ok(serde_json::from_value(s.result).unwrap()),
+            Ok(RpcResponse::Error(e)) => Err(e.error.message),
+            Err(e) => Err(e.to_string()),
+        }
+    }
+
+    fn auth_token(&self) -> String {
+        // Header
+        let header = jsonwebtoken::Header::default();
+        // Claims
+        let valid_iat = SystemTime::now()
+            .duration_since(UNIX_EPOCH)
+            .unwrap()
+            .as_secs() as usize;
+        let claims = json!({"iat": valid_iat});
+        // Encoding Key
+        let decoded_secret = hex::decode(self.secret.clone()).unwrap();
+        let encoding_key = jsonwebtoken::EncodingKey::from_secret(decoded_secret.as_ref());
+        // JWT Token
+        jsonwebtoken::encode(&header, &claims, &encoding_key).unwrap()
+    }
+
+    fn capabilities() -> Vec<String> {
+        vec![
+            "engine_exchangeCapabilities".to_owned(),
+            "engine_forkchoiceUpdatedV3".to_owned(),
+            "engine_getPayloadV3".to_owned(),
+            "engine_newPayloadV3".to_owned(),
+        ]
+    }
+}

crates/l2/operator/mod.rs

@@ -1,14 +1,23 @@
+use ethereum_rust_storage::Store;
 use std::net::{IpAddr, Ipv4Addr};
 
 pub mod block_producer;
+pub mod engine;
 pub mod l1_tx_sender;
 pub mod l1_watcher;
 pub mod proof_data_provider;
 
-pub async fn start_operator() {
+pub async fn start_operator(store: Store) {
     let l1_tx_sender = tokio::spawn(l1_tx_sender::start_l1_tx_sender());
     let l1_watcher = tokio::spawn(l1_watcher::start_l1_watcher());
-    let block_producer = tokio::spawn(block_producer::start_block_producer());
+    let current_block_hash = {
+        let current_block_number = store.get_latest_block_number().unwrap().unwrap();
+        store
+            .get_canonical_block_hash(current_block_number)
+            .unwrap()
+            .unwrap()
+    };
+    let block_producer = tokio::spawn(block_producer::start_block_producer(current_block_hash));
     let proof_data_provider = tokio::spawn(proof_data_provider::start_proof_data_provider(
         IpAddr::V4(Ipv4Addr::new(127, 0, 0, 1)),
         3000,

crates/networking/rpc/Cargo.toml

@@ -21,7 +21,7 @@ ethereum_rust-net.workspace = true
 ethereum_rust-rlp.workspace = true
 hex.workspace = true
 axum-extra = {version = "0.9.3", features = ["typed-header"]}
-jsonwebtoken = "9.3.0"
+jsonwebtoken.workspace = true
 rand.workspace = true
 
 [dev-dependencies]

crates/networking/rpc/engine/fork_choice.rs

@@ -12,6 +12,7 @@ use crate::{
         fork_choice::{ForkChoiceResponse, ForkChoiceState, PayloadAttributesV3},
         payload::PayloadStatus,
     },
+    utils::RpcRequest,
     RpcErr, RpcHandler,
 };
 
@@ -22,6 +23,19 @@ pub struct ForkChoiceUpdatedV3 {
     pub payload_attributes: Option<PayloadAttributesV3>,
 }
 
+impl From<ForkChoiceUpdatedV3> for RpcRequest {
+    fn from(val: ForkChoiceUpdatedV3) -> Self {
+        RpcRequest {
+            method: "engine_forkchoiceUpdatedV3".to_string(),
+            params: Some(vec![
+                serde_json::json!(val.fork_choice_state),
+                serde_json::json!(val.payload_attributes),
+            ]),
+            ..Default::default()
+        }
+    }
+}
+
 impl RpcHandler for ForkChoiceUpdatedV3 {
     fn parse(params: &Option<Vec<Value>>) -> Result<Self, RpcErr> {
         let params = params