1 files changed, 6 insertions, 0 deletions
diff --git a/src/interfaces/chain.h b/src/interfaces/chain.h
index 3778ab9a8b..7504f4cfb6 100644
--- a/src/interfaces/chain.h
+++ b/src/interfaces/chain.h
@@ -150,6 +150,12 @@ public:
     //! or contents.
     virtual bool findBlock(const uint256& hash, const FoundBlock& block={}) = 0;
 
+    //! Return whether block descends from a specified ancestor, and
+    //! optionally return ancestor information.
+    virtual bool findAncestorByHash(const uint256& block_hash,
+        const uint256& ancestor_hash,
+        const FoundBlock& ancestor_out={}) = 0;
+
     //! Look up unspent output information. Returns coins in the mempool and in
     //! the current chain UTXO set. Iterates through all the keys in the map and
     //! populates the values.