Enforce restricted # pool txs served via RPC + optimize chunked reqs [release-v0.18]

- `/getblocks.bin` respects the `RESTRICTED_TX_COUNT` (=100) when
returning pool txs via a restricted RPC daemon.
- A restricted RPC daemon includes a max of `RESTRICTED_TX_COUNT` txs
in the `added_pool_txs` field, and returns any remaining pool hashes
in the `remaining_added_pool_txids` field. The client then requests
the remaining txs via `/gettransactions` in chunks.
- `/gettransactions` no longer does expensive no-ops for ALL pool txs
if the client requests a subset of pool txs. Instead it searches for
the txs the client explicitly requests.
- Reset `m_pool_info_query_time` when a user:
  (1) rescans the chain (so the wallet re-requests the whole pool)
  (2) changes the daemon their wallets points to (a new daemon would
      have a different view of the pool)
- `/getblocks.bin` respects the `req.prune` field when returning
pool txs.
- Pool extension fields in response to `/getblocks.bin` are optional
with default 0'd values.

1 files changed, 7 insertions, 2 deletions

diff --git a/src/cryptonote_core/cryptonote_core.cpp b/src/cryptonote_core/cryptonote_core.cpp
index b252f49de..d34c92723 100644
--- a/src/cryptonote_core/cryptonote_core.cpp
+++ b/src/cryptonote_core/cryptonote_core.cpp
@@ -1727,6 +1727,11 @@ namespace cryptonote
     return true;
   }
   //-----------------------------------------------------------------------------------------------
+  bool core::get_pool_transactions_info(const std::vector<crypto::hash>& txids, std::vector<std::pair<crypto::hash, tx_memory_pool::tx_details>>& txs, bool include_sensitive_txes) const
+  {
+    return m_mempool.get_transactions_info(txids, txs, include_sensitive_txes);
+  }
+  //-----------------------------------------------------------------------------------------------
   bool core::get_pool_transactions(std::vector<transaction>& txs, bool include_sensitive_data) const
   {
     m_mempool.get_transactions(txs, include_sensitive_data);
@@ -1739,9 +1744,9 @@ namespace cryptonote
     return true;
   }
   //-----------------------------------------------------------------------------------------------
-  bool core::get_pool_info(time_t start_time, bool include_sensitive_txes, std::vector<tx_memory_pool::tx_details>& added_txs, std::vector<crypto::hash>& removed_txs, bool& incremental) const
+  bool core::get_pool_info(time_t start_time, bool include_sensitive_txes, size_t max_tx_count, std::vector<std::pair<crypto::hash, tx_memory_pool::tx_details>>& added_txs, std::vector<crypto::hash>& remaining_added_txids, std::vector<crypto::hash>& removed_txs, bool& incremental) const
   {
-    return m_mempool.get_pool_info(start_time, include_sensitive_txes, added_txs, removed_txs, incremental);
+    return m_mempool.get_pool_info(start_time, include_sensitive_txes, max_tx_count, added_txs, remaining_added_txids, removed_txs, incremental);
   }
   //-----------------------------------------------------------------------------------------------
   bool core::get_pool_transaction_stats(struct txpool_stats& stats, bool include_sensitive_data) const