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diff --git a/src/index/blockfilterindex.h b/src/index/blockfilterindex.h
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+// Copyright (c) 2018 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#ifndef BITCOIN_INDEX_BLOCKFILTERINDEX_H
+#define BITCOIN_INDEX_BLOCKFILTERINDEX_H
+
+#include <blockfilter.h>
+#include <chain.h>
+#include <flatfile.h>
+#include <index/base.h>
+
+/**
+ * BlockFilterIndex is used to store and retrieve block filters, hashes, and headers for a range of
+ * blocks by height. An index is constructed for each supported filter type with its own database
+ * (ie. filter data for different types are stored in separate databases).
+ *
+ * This index is used to serve BIP 157 net requests.
+ */
+class BlockFilterIndex final : public BaseIndex
+{
+private:
+    BlockFilterType m_filter_type;
+    std::string m_name;
+    std::unique_ptr<BaseIndex::DB> m_db;
+
+    FlatFilePos m_next_filter_pos;
+    std::unique_ptr<FlatFileSeq> m_filter_fileseq;
+
+    bool ReadFilterFromDisk(const FlatFilePos& pos, BlockFilter& filter) const;
+    size_t WriteFilterToDisk(FlatFilePos& pos, const BlockFilter& filter);
+
+protected:
+    bool Init() override;
+
+    bool CommitInternal(CDBBatch& batch) override;
+
+    bool WriteBlock(const CBlock& block, const CBlockIndex* pindex) override;
+
+    bool Rewind(const CBlockIndex* current_tip, const CBlockIndex* new_tip) override;
+
+    BaseIndex::DB& GetDB() const override { return *m_db; }
+
+    const char* GetName() const override { return m_name.c_str(); }
+
+public:
+    /** Constructs the index, which becomes available to be queried. */
+    explicit BlockFilterIndex(BlockFilterType filter_type,
+                              size_t n_cache_size, bool f_memory = false, bool f_wipe = false);
+
+    BlockFilterType GetFilterType() const { return m_filter_type; }
+
+    /** Get a single filter by block. */
+    bool LookupFilter(const CBlockIndex* block_index, BlockFilter& filter_out) const;
+
+    /** Get a single filter header by block. */
+    bool LookupFilterHeader(const CBlockIndex* block_index, uint256& header_out) const;
+
+    /** Get a range of filters between two heights on a chain. */
+    bool LookupFilterRange(int start_height, const CBlockIndex* stop_index,
+                           std::vector<BlockFilter>& filters_out) const;
+
+    /** Get a range of filter hashes between two heights on a chain. */
+    bool LookupFilterHashRange(int start_height, const CBlockIndex* stop_index,
+                               std::vector<uint256>& hashes_out) const;
+};
+
+/**
+ * Get a block filter index by type. Returns nullptr if index has not been initialized or was
+ * already destroyed.
+ */
+BlockFilterIndex* GetBlockFilterIndex(BlockFilterType filter_type);
+
+/** Iterate over all running block filter indexes, invoking fn on each. */
+void ForEachBlockFilterIndex(std::function<void (BlockFilterIndex&)> fn);
+
+/**
+ * Initialize a block filter index for the given type if one does not already exist. Returns true if
+ * a new index is created and false if one has already been initialized.
+ */
+bool InitBlockFilterIndex(BlockFilterType filter_type,
+                          size_t n_cache_size, bool f_memory = false, bool f_wipe = false);
+
+/**
+ * Destroy the block filter index with the given type. Returns false if no such index exists. This
+ * just releases the allocated memory and closes the database connection, it does not delete the
+ * index data.
+ */
+bool DestroyBlockFilterIndex(BlockFilterType filter_type);
+
+/** Destroy all open block filter indexes. */
+void DestroyAllBlockFilterIndexes();
+
+#endif // BITCOIN_INDEX_BLOCKFILTERINDEX_H