From 479dedaa8254705a3013c077c5619d202b3fa3d6 Mon Sep 17 00:00:00 2001
From: Jonathan LEI <me@xjonathan.dev>
Date: Fri, 26 Apr 2024 03:39:48 +0800
Subject: [PATCH] feat: add checksum to pending block hash

Previously, the pseudo pending block hash format always ends with zeros,
which does not work with the block hash truncation in `bstream`. This
commit fixes it but clusters need to be re-synced.
---
 Cargo.lock  | 12 ++++++++++++
 Cargo.toml  |  1 +
 src/main.rs | 31 ++++++++++++++++++-------------
 3 files changed, 31 insertions(+), 13 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index 609047b..4766e14 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1071,6 +1071,7 @@ dependencies = [
  "serde",
  "serde_json",
  "serde_with",
+ "sha1",
  "starknet",
  "tokio",
  "url",
@@ -1697,6 +1698,17 @@ dependencies = [
  "syn 2.0.28",
 ]
 
+[[package]]
+name = "sha1"
+version = "0.10.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e3bf829a2d51ab4a5ddf1352d8470c140cadc8301b2ae1789db023f01cedd6ba"
+dependencies = [
+ "cfg-if",
+ "cpufeatures",
+ "digest",
+]
+
 [[package]]
 name = "sha2"
 version = "0.10.7"
diff --git a/Cargo.toml b/Cargo.toml
index 812ae43..15c8574 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -15,6 +15,7 @@ reqwest = { version = "0.11.18", default-features = false, features = ["rustls-t
 serde = "1.0.180"
 serde_json = "1.0.104"
 serde_with = "2.3.2"
+sha1 = "0.10.6"
 starknet = { git = "https://github.com/xJonathanLEI/starknet-rs", rev = "6cadb198644cf5e942187896c2e6bb3ecc9edc6e" }
 tokio = { version = "1.29.1", features = ["full"] }
 url = "2.4.0"
diff --git a/src/main.rs b/src/main.rs
index b6d8736..80a0c71 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -5,6 +5,7 @@ use clap::Parser;
 use log::{debug, error, info};
 use serde::{Deserialize, Serialize};
 use serde_with::serde_as;
+use sha1::Digest;
 use starknet::{
     core::{
         serde::unsigned_field_element::UfeHex,
@@ -96,19 +97,19 @@ impl MaybePendingBlock {
                 pseudo_height,
                 block,
             } => {
-                // +-------+-----------+--------------+---------------------+------------------+
-                // | Fixed | "PENDING" | Block Number | Transaction Count   | Reserved         |
-                // | 1 byte| 7 bytes   | 8 bytes      | 4 bytes             | 12 bytes         |
-                // +-------+-----------+--------------+---------------------+------------------+
-                // |  00   |    50     |      NN      |         NN          |        00        |
-                // |       |    45     |      NN      |         NN          |        00        |
-                // |       |    4E     |      NN      |         NN          |        00        |
-                // |       |    44     |      NN      |         NN          |        00        |
-                // |       |    49     |      NN      |                     |        00        |
-                // |       |    4E     |      NN      |                     |        00        |
-                // |       |    47     |      NN      |                     |        00        |
-                // |       |           |      NN      |                     |        00        |
-                // +-------+-----------+--------------+---------------------+------------------+
+                // +--------+-----------+--------------+-------------------+----------+----------+
+                // | Fixed  | "PENDING" | Block Number | Transaction Count | Reserved | Checksum |
+                // | 1 byte | 7 bytes   | 8 bytes      | 4 bytes           | 8 bytes  | 4 bytes  |
+                // +--------+-----------+--------------+-------------------+----------+----------+
+                // |  00    |    50     |      NN      |         NN        |    00    |   NN     |
+                // |        |    45     |      NN      |         NN        |    00    |   NN     |
+                // |        |    4E     |      NN      |         NN        |    00    |   NN     |
+                // |        |    44     |      NN      |         NN        |    00    |   NN     |
+                // |        |    49     |      NN      |                   |    00    |          |
+                // |        |    4E     |      NN      |                   |    00    |          |
+                // |        |    47     |      NN      |                   |    00    |          |
+                // |        |           |      NN      |                   |    00    |          |
+                // +--------+-----------+--------------+-------------------+----------+----------+
 
                 let mut buffer = [0u8; 32];
                 buffer[1] = b'P';
@@ -123,6 +124,10 @@ impl MaybePendingBlock {
                 buffer[(8 + 8)..(8 + 8 + 4)]
                     .copy_from_slice(&u32::to_be_bytes(block.transactions.len() as u32));
 
+                let mut hasher = sha1::Sha1::new();
+                hasher.update(&buffer[..(8 + 8 + 4 + 8)]);
+                buffer[(8 + 8 + 4 + 8)..].copy_from_slice(&hasher.finalize()[0..4]);
+
                 // This cannot fail as the buffer is always in range
                 FieldElement::from_bytes_be(&buffer).unwrap()
             }