Print a warning in case of non-empty badBlocks

bin/full-node/src/run/consensus_service.rs

@@ -950,6 +950,7 @@ impl SyncBackground {
                     let _jaeger_span = self.jaeger_service.block_body_verify_span(&hash_to_verify);
 
                     let mut verify = verify.start(unix_time, ());
+                    // TODO: check this block against the chain spec's badBlocks
                     loop {
                         match verify {
                             all::BlockVerification::Error {

bin/light-base/src/lib.rs

@@ -729,6 +729,7 @@ impl<TChain, TPlat: Platform> Client<TChain, TPlat> {
                             .as_ref()
                             .finalized_block_header
                             .hash(chain_spec.block_number_bytes().into());
+                        let has_bad_blocks = chain_spec.bad_blocks_hashes().count() != 0;
 
                         let running_chain = start_services(
                             log_name.clone(),
@@ -777,6 +778,15 @@ impl<TChain, TPlat: Platform> Client<TChain, TPlat> {
                             );
                         }
 
+                        // TODO: remove after https://github.com/paritytech/smoldot/issues/2584
+                        if has_bad_blocks {
+                            log::warn!(
+                                target: "smoldot",
+                                "Chain {} has bad blocks in its chain specification. Bad blocks \
+                                are not implemented in the light client", log_name
+                            );
+                        }
+
                         running_chain
                     };
 

bin/wasm-node/CHANGELOG.md

@@ -7,6 +7,7 @@
 - The GRANDPA warp sync algorithm now downloads Merkle proofs of all the necessary storage items at once, rather than one by one sequentially. This removes approximately 11 networking round-trips and thus significantly reduces the time the warp syncing takes. ([#2578](https://github.com/paritytech/smoldot/pull/2578))
 - The GRANDPA warp sync algorithm now works on AURA-based chains. It previously only worked for chains that are using BABE. Note that GRANDPA warp sync is irrelevant for parachains. ([#2581](https://github.com/paritytech/smoldot/pull/2581))
 - The GRANDPA warp sync implementation has been considerably refactored. It is possible that unintended changes in behaviour have accidentally been introduced. ([#2578](https://github.com/paritytech/smoldot/pull/2578))
+- A warning is now printed if the `badBlocks` field in a chain specification is not empty. Bad blocks are not supported by the smoldot light client. ([#2585](https://github.com/paritytech/smoldot/pull/2585))
 
 ## 0.6.27 - 2022-07-29
 

src/chain_spec.rs

@@ -268,6 +268,16 @@ impl ChainSpec {
         }
     }
 
+    /// Returns a list of hashes of block headers that should always be considered as invalid.
+    pub fn bad_blocks_hashes(&'_ self) -> impl Iterator<Item = &'_ [u8; 32]> + '_ {
+        self.client_spec
+            .bad_blocks
+            .as_ref()
+            .into_iter()
+            .flat_map(|l| l.iter())
+            .map(|h| &h.0)
+    }
+
     /// Returns the list of bootnode addresses found in the chain spec.
     ///
     /// Bootnode addresses that have failed to be parsed are returned as well in the form of

src/chain_spec/structs.rs

@@ -60,7 +60,6 @@ pub(super) struct ClientSpec {
     pub(super) properties: Option<Box<serde_json::value::RawValue>>,
     // TODO: make use of this
     pub(super) fork_blocks: Option<Vec<(u64, HashHexString)>>,
-    // TODO: make use of this
     pub(super) bad_blocks: Option<HashSet<HashHexString, FnvBuildHasher>>,
     // Unused but for some reason still part of the chain specs.
     #[serde(default, skip_serializing)]