feat: implement Filecoin.EthGetBlockByNumber

CHANGELOG.md

@@ -52,6 +52,9 @@
 - [#4184](https://github.com/ChainSafe/forest/pull/4184) Added
   `--no-healthcheck` flag to `forest` to disable the healthcheck endpoint.
 
+- [#4183](https://github.com/ChainSafe/forest/issues/4183) Add support for the
+  `Filecoin.EthGetBlockByNumber` RPC method.
+
 ### Changed
 
 - [#4170](https://github.com/ChainSafe/forest/pull/4170) Change the default

Cargo.toml

@@ -76,6 +76,8 @@ git-version = "0.3"
 group = "0.13"
 hex = { version = "0.4", features = ["serde"] }
 http = "1.0"
+keccak-hash = "0.10.0"
+rlp = "0.5.2"
 # TODO(forest): https://github.com/ChainSafe/forest/issues/3961
 #               bump hyper to 1.0 after https://github.com/paritytech/jsonrpsee/issues/1257
 http02 = { version = "0.2", package = "http" }

src/lotus_json/mod.rs

@@ -321,6 +321,39 @@ pub mod hexify_bytes {
     }
 }
 
+pub mod hexify_vec_bytes {
+    use super::*;
+    use std::fmt::Write;
+
+    pub fn serialize<S>(value: &[u8], serializer: S) -> Result<S::Ok, S::Error>
+    where
+        S: Serializer,
+    {
+        let mut s = String::with_capacity(2 + value.len() * 2);
+        s.push_str("0x");
+        for b in value {
+            write!(s, "{:02x}", b).expect("failed to write to string");
+        }
+        serializer.serialize_str(&s)
+    }
+
+    pub fn deserialize<'de, D>(deserializer: D) -> Result<Vec<u8>, D::Error>
+    where
+        D: Deserializer<'de>,
+    {
+        let s = String::deserialize(deserializer)?;
+        if (s.len() >= 2 && s.len() % 2 == 0) && s.get(..2).expect("failed to get prefix") == "0x" {
+            let result: Result<Vec<u8>, _> = (2..s.len())
+                .step_by(2)
+                .map(|i| u8::from_str_radix(s.get(i..i + 2).expect("failed to get slice"), 16))
+                .collect();
+            result.map_err(serde::de::Error::custom)
+        } else {
+            Err(serde::de::Error::custom("Invalid hex"))
+        }
+    }
+}
+
 /// Usage: `#[serde(with = "hexify")]`
 pub mod hexify {
     use super::*;

src/rpc/auth_layer.rs

@@ -167,6 +167,7 @@ static ACCESS_MAP: Lazy<HashMap<&str, Access>> = Lazy::new(|| {
     access.insert(eth::ETH_GAS_PRICE, Access::Read);
     access.insert(eth::ETH_GET_BALANCE, Access::Read);
     access.insert(eth::ETH_SYNCING, Access::Read);
+    access.insert(eth::ETH_GET_BLOCK_BY_NUMBER, Access::Read);
     access.insert(eth::WEB3_CLIENT_VERSION, Access::Read);
 
     // Pubsub API