monerod can now sync from pruned blocks

If the peer (whether pruned or not itself) supports sending pruned blocks
to syncing nodes, the pruned version will be sent along with the hash
of the pruned data and the block weight. The original tx hashes can be
reconstructed from the pruned txes and theur prunable data hash. Those
hashes and the block weights are hashes and checked against the set of
precompiled hashes, ensuring the data we received is the original data.
It is currently not possible to use this system when not using the set
of precompiled hashes, since block weights can not otherwise be checked
for validity.

This is off by default for now, and is enabled by --sync-pruned-blocks

1 files changed, 4 insertions, 2 deletions

diff --git a/src/blockchain_db/lmdb/db_lmdb.cpp b/src/blockchain_db/lmdb/db_lmdb.cpp
index 760e380a9..8e2b5bebf 100644
--- a/src/blockchain_db/lmdb/db_lmdb.cpp
+++ b/src/blockchain_db/lmdb/db_lmdb.cpp
@@ -2056,7 +2056,7 @@ bool BlockchainLMDB::prune_worker(int mode, uint32_t pruning_seed)
           ++n_prunable_records;
           result = mdb_cursor_get(c_txs_prunable, &k, &v, MDB_SET);
           if (result == MDB_NOTFOUND)
-            MWARNING("Already pruned at height " << block_height << "/" << blockchain_height);
+            MDEBUG("Already pruned at height " << block_height << "/" << blockchain_height);
           else if (result)
             throw0(DB_ERROR(lmdb_error("Failed to find transaction prunable data: ", result).c_str()));
           else
@@ -2152,7 +2152,7 @@ bool BlockchainLMDB::prune_worker(int mode, uint32_t pruning_seed)
         {
           ++n_prunable_records;
           if (result == MDB_NOTFOUND)
-            MWARNING("Already pruned at height " << block_height << "/" << blockchain_height);
+            MDEBUG("Already pruned at height " << block_height << "/" << blockchain_height);
           else
           {
             MDEBUG("Pruning at height " << block_height << "/" << blockchain_height);
@@ -2994,6 +2994,8 @@ bool BlockchainLMDB::get_tx_blob(const crypto::hash& h, cryptonote::blobdata &bd
     return false;
   else if (get_result)
     throw0(DB_ERROR(lmdb_error("DB error attempting to fetch tx from hash", get_result).c_str()));
+  else if (result1.mv_size == 0)
+    return false;
 
   bd.assign(reinterpret_cast<char*>(result0.mv_data), result0.mv_size);
   bd.append(reinterpret_cast<char*>(result1.mv_data), result1.mv_size);