Merge pull request #442

43bca0d blockchain_utilities: new blockchain_dump diagnostic tool (moneromooo-monero)
5f397e4 Add functions to iterate through blocks, txes, outputs, key images (moneromooo-monero)
0a5a5e8 db_bdb: record numbers for recno databases start at 1 (moneromooo-monero)
50dfdc0 db_bdb: DB_KEYEMPTY is also not found for non-top recon fields (moneromooo-monero)
572780e blockchain_db: use the DNE exceptions where appropriate (moneromooo-monero)

11 files changed, 843 insertions, 21 deletions

diff --git a/src/blockchain_db/berkeleydb/db_bdb.cpp b/src/blockchain_db/berkeleydb/db_bdb.cpp
index bd579ed38..6560ce5c2 100644
--- a/src/blockchain_db/berkeleydb/db_bdb.cpp
+++ b/src/blockchain_db/berkeleydb/db_bdb.cpp
@@ -385,7 +385,7 @@ void BlockchainBDB::remove_tx_outputs(const crypto::hash& tx_hash, const transac
     auto result = cur->get(&k, &v, DB_SET);
     if (result == DB_NOTFOUND)
     {
-        throw0(DB_ERROR("Attempting to remove a tx's outputs, but none found."));
+        throw0(OUTPUT_DNE("Attempting to remove a tx's outputs, but none found."));
     }
     else if (result)
     {
@@ -533,6 +533,126 @@ void BlockchainBDB::remove_spent_key(const crypto::key_image& k_image)
         throw1(DB_ERROR("Error adding removal of key image to db transaction"));
 }
 
+bool BlockchainBDB::for_all_key_images(std::function<bool(const crypto::key_image&)> f) const
+{
+    LOG_PRINT_L3("BlockchainBDB::" << __func__);
+    check_open();
+
+    bdb_cur cur(DB_DEFAULT_TX, m_spent_keys);
+
+    Dbt_copy<crypto::key_image> k;
+    Dbt_copy<char> v;
+    bool ret = true;
+    int result;
+    while ((result = cur->get(&k, &v, DB_NEXT)) == 0)
+    {
+      if (!f(k))
+      {
+        ret = false;
+        break;
+      }
+    }
+    if (result != DB_NOTFOUND)
+      ret = false;
+
+    cur.close();
+    return ret;
+}
+
+bool BlockchainBDB::for_all_blocks(std::function<bool(uint64_t, const crypto::hash&, const cryptonote::block&)> f) const
+{
+    LOG_PRINT_L3("BlockchainBDB::" << __func__);
+    check_open();
+
+    bdb_cur cur(DB_DEFAULT_TX, m_blocks);
+
+    Dbt_copy<uint64_t> k;
+    Dbt_safe v;
+    bool ret = true;
+    int result;
+    while ((result = cur->get(&k, &v, DB_NEXT)) == 0)
+    {
+      uint64_t height = k - 1;
+      blobdata bd;
+      bd.assign(reinterpret_cast<char*>(v.get_data()), v.get_size());
+      block b;
+      if (!parse_and_validate_block_from_blob(bd, b))
+          throw0(DB_ERROR("Failed to parse block from blob retrieved from the db"));
+      crypto::hash hash;
+      if (!get_block_hash(b, hash))
+          throw0(DB_ERROR("Failed to get block hash from blob retrieved from the db"));
+      if (!f(height, hash, b))
+      {
+        ret = false;
+        break;
+      }
+    }
+    if (result != DB_NOTFOUND)
+      ret = false;
+
+    cur.close();
+    return ret;
+}
+
+bool BlockchainBDB::for_all_transactions(std::function<bool(const crypto::hash&, const cryptonote::transaction&)> f) const
+{
+    LOG_PRINT_L3("BlockchainBDB::" << __func__);
+    check_open();
+
+    bdb_cur cur(DB_DEFAULT_TX, m_txs);
+
+    Dbt_copy<crypto::hash> k;
+    Dbt_safe v;
+    bool ret = true;
+    int result;
+    while ((result = cur->get(&k, &v, DB_NEXT)) == 0)
+    {
+      blobdata bd;
+      bd.assign(reinterpret_cast<char*>(v.get_data()), v.get_size());
+      transaction tx;
+      if (!parse_and_validate_tx_from_blob(bd, tx))
+          throw0(DB_ERROR("Failed to parse tx from blob retrieved from the db"));
+      if (!f(k, tx))
+      {
+        ret = false;
+        break;
+      }
+    }
+    if (result != DB_NOTFOUND)
+      ret = false;
+
+    cur.close();
+    return ret;
+}
+
+bool BlockchainBDB::for_all_outputs(std::function<bool(uint64_t amount, const crypto::hash &tx_hash, size_t tx_idx)> f) const
+{
+    LOG_PRINT_L3("BlockchainBDB::" << __func__);
+    check_open();
+
+    bdb_cur cur(DB_DEFAULT_TX, m_output_amounts);
+
+    Dbt_copy<uint64_t> k;
+    Dbt_copy<uint32_t> v;
+    bool ret = true;
+    int result;
+    while ((result = cur->get(&k, &v, DB_NEXT)) == 0)
+    {
+      uint32_t global_index = v - 1;
+      tx_out_index toi = get_output_tx_and_index_from_global(global_index);
+      if (!f(k, toi.first, toi.second))
+      {
+        ret = false;
+        break;
+      }
+    }
+    if (result != DB_NOTFOUND)
+      ret = false;
+
+    cur.close();
+    return ret;
+}
+
 blobdata BlockchainBDB::output_to_blob(const tx_out& output) const
 {
     LOG_PRINT_L3("BlockchainBDB::" << __func__);
@@ -977,7 +1097,7 @@ block BlockchainBDB::get_block_from_height(const uint64_t& height) const
     auto get_result = m_blocks->get(DB_DEFAULT_TX, &key, &result, 0);
     if (get_result == DB_NOTFOUND)
     {
-        throw0(DB_ERROR(std::string("Attempt to get block from height ").append(boost::lexical_cast<std::string>(height)).append(" failed -- block not in db").c_str()));
+        throw0(BLOCK_DNE(std::string("Attempt to get block from height ").append(boost::lexical_cast<std::string>(height)).append(" failed -- block not in db").c_str()));
     }
     else if (get_result)
         throw0(DB_ERROR("Error attempting to retrieve a block from the db"));
@@ -1002,7 +1122,7 @@ uint64_t BlockchainBDB::get_block_timestamp(const uint64_t& height) const
     auto get_result = m_block_timestamps->get(DB_DEFAULT_TX, &key, &result, 0);
     if (get_result == DB_NOTFOUND)
     {
-        throw0(DB_ERROR(std::string("Attempt to get timestamp from height ").append(boost::lexical_cast<std::string>(height)).append(" failed -- timestamp not in db").c_str()));
+        throw0(BLOCK_DNE(std::string("Attempt to get timestamp from height ").append(boost::lexical_cast<std::string>(height)).append(" failed -- timestamp not in db").c_str()));
     }
     else if (get_result)
         throw0(DB_ERROR("Error attempting to retrieve a timestamp from the db"));
@@ -1034,7 +1154,7 @@ size_t BlockchainBDB::get_block_size(const uint64_t& height) const
     auto get_result = m_block_sizes->get(DB_DEFAULT_TX, &key, &result, 0);
     if (get_result == DB_NOTFOUND)
     {
-        throw0(DB_ERROR(std::string("Attempt to get block size from height ").append(boost::lexical_cast<std::string>(height)).append(" failed -- block size not in db").c_str()));
+        throw0(BLOCK_DNE(std::string("Attempt to get block size from height ").append(boost::lexical_cast<std::string>(height)).append(" failed -- block size not in db").c_str()));
     }
     else if (get_result)
         throw0(DB_ERROR("Error attempting to retrieve a block size from the db"));
@@ -1052,7 +1172,7 @@ difficulty_type BlockchainBDB::get_block_cumulative_difficulty(const uint64_t& h
     auto get_result = m_block_diffs->get(DB_DEFAULT_TX, &key, &result, 0);
     if (get_result == DB_NOTFOUND)
     {
-        throw0(DB_ERROR(std::string("Attempt to get cumulative difficulty from height ").append(boost::lexical_cast<std::string>(height)).append(" failed -- difficulty not in db").c_str()));
+        throw0(BLOCK_DNE(std::string("Attempt to get cumulative difficulty from height ").append(boost::lexical_cast<std::string>(height)).append(" failed -- difficulty not in db").c_str()));
     }
     else if (get_result)
         throw0(DB_ERROR("Error attempting to retrieve a cumulative difficulty from the db"));
@@ -1087,7 +1207,7 @@ uint64_t BlockchainBDB::get_block_already_generated_coins(const uint64_t& height
     auto get_result = m_block_coins->get(DB_DEFAULT_TX, &key, &result, 0);
     if (get_result == DB_NOTFOUND)
     {
-        throw0(DB_ERROR(std::string("Attempt to get generated coins from height ").append(boost::lexical_cast<std::string>(height)).append(" failed -- block size not in db").c_str()));
+        throw0(BLOCK_DNE(std::string("Attempt to get generated coins from height ").append(boost::lexical_cast<std::string>(height)).append(" failed -- block size not in db").c_str()));
     }
     else if (get_result)
         throw0(DB_ERROR("Error attempting to retrieve a total generated coins from the db"));
@@ -1315,11 +1435,11 @@ output_data_t BlockchainBDB::get_output_key(const uint64_t& global_index) const
     LOG_PRINT_L3("BlockchainBDB::" << __func__);
     check_open();
 
-    Dbt_copy<uint32_t> k(global_index);
+    Dbt_copy<uint32_t> k(global_index + 1);
     Dbt_copy<output_data_t> v;
     auto get_result = m_output_keys->get(DB_DEFAULT_TX, &k, &v, 0);
     if (get_result == DB_NOTFOUND)
-        throw0(DB_ERROR("Attempting to get output pubkey by global index, but key does not exist"));
+        throw1(OUTPUT_DNE("Attempting to get output pubkey by global index, but key does not exist"));
     else if (get_result)
         throw0(DB_ERROR("Error attempting to retrieve an output pubkey from the db"));
 
@@ -1467,7 +1587,7 @@ tx_out_index BlockchainBDB::get_output_tx_and_index_from_global(const uint64_t&
     LOG_PRINT_L3("BlockchainBDB::" << __func__);
     check_open();
 
-    Dbt_copy<uint32_t> k(index);
+    Dbt_copy<uint32_t> k(index + 1);
     Dbt_copy<crypto::hash > v;
 
     auto get_result = m_output_txs->get(DB_DEFAULT_TX, &k, &v, 0);
@@ -1826,7 +1946,7 @@ void BlockchainBDB::get_output_key(const uint64_t &amount, const std::vector<uin
     {
         for (const uint64_t &index : global_indices)
         {
-            Dbt_copy<uint32_t> k(index);
+            Dbt_copy<uint32_t> k(index + 1);
             Dbt_copy<output_data_t> v;
 
             auto get_result = m_output_keys->get(DB_DEFAULT_TX, &k, &v, 0);
@@ -1880,7 +2000,7 @@ uint64_t BlockchainBDB::get_hard_fork_starting_height(uint8_t version) const
     Dbt_copy<uint64_t> result;
 
     auto get_result = m_hf_starting_heights->get(DB_DEFAULT_TX, &key, &result, 0);
-    if (get_result == DB_NOTFOUND)
+    if (get_result == DB_NOTFOUND || get_result == DB_KEYEMPTY)
         return std::numeric_limits<uint64_t>::max();
     else if (get_result)
         throw0(DB_ERROR("Error attempting to retrieve hard fork starting height from the db"));
@@ -1908,7 +2028,9 @@ uint8_t BlockchainBDB::get_hard_fork_version(uint64_t height) const
     Dbt_copy<uint8_t> result;
 
     auto get_result = m_hf_versions->get(DB_DEFAULT_TX, &key, &result, 0);
-    if (get_result == DB_NOTFOUND || get_result)
+    if (get_result == DB_NOTFOUND || get_result == DB_KEYEMPTY)
+        throw0(OUTPUT_DNE("Error attempting to retrieve hard fork version from the db"));
+    else if (get_result)
         throw0(DB_ERROR("Error attempting to retrieve hard fork version from the db"));
 
     return result;
diff --git a/src/blockchain_db/berkeleydb/db_bdb.h b/src/blockchain_db/berkeleydb/db_bdb.h
index 54edcf0ad..b51d745d8 100644
--- a/src/blockchain_db/berkeleydb/db_bdb.h
+++ b/src/blockchain_db/berkeleydb/db_bdb.h
@@ -375,6 +375,11 @@ private:
 
   void get_output_global_indices(const uint64_t& amount, const std::vector<uint64_t> &offsets, std::vector<uint64_t> &global_indices);
 
+  virtual bool for_all_key_images(std::function<bool(const crypto::key_image&)>) const;
+  virtual bool for_all_blocks(std::function<bool(uint64_t, const crypto::hash&, const cryptonote::block&)>) const;
+  virtual bool for_all_transactions(std::function<bool(const crypto::hash&, const cryptonote::transaction&)>) const;
+  virtual bool for_all_outputs(std::function<bool(uint64_t amount, const crypto::hash &tx_hash, size_t tx_idx)> f) const;
+
   // Hard fork related storage
   virtual void set_hard_fork_starting_height(uint8_t version, uint64_t height);
   virtual uint64_t get_hard_fork_starting_height(uint8_t version) const;
diff --git a/src/blockchain_db/blockchain_db.h b/src/blockchain_db/blockchain_db.h
index 24bf4024d..1666e57c5 100644
--- a/src/blockchain_db/blockchain_db.h
+++ b/src/blockchain_db/blockchain_db.h
@@ -493,6 +493,11 @@ public:
   // returns true if key image <img> is present in spent key images storage
   virtual bool has_key_image(const crypto::key_image& img) const = 0;
 
+  virtual bool for_all_key_images(std::function<bool(const crypto::key_image&)>) const = 0;
+  virtual bool for_all_blocks(std::function<bool(uint64_t, const crypto::hash&, const cryptonote::block&)>) const = 0;
+  virtual bool for_all_transactions(std::function<bool(const crypto::hash&, const cryptonote::transaction&)>) const = 0;
+  virtual bool for_all_outputs(std::function<bool(uint64_t amount, const crypto::hash &tx_hash, size_t tx_idx)> f) const = 0;
+
   // Hard fork related storage
   virtual void set_hard_fork_starting_height(uint8_t version, uint64_t height) = 0;
   virtual uint64_t get_hard_fork_starting_height(uint8_t version) const = 0;
diff --git a/src/blockchain_db/lmdb/db_lmdb.cpp b/src/blockchain_db/lmdb/db_lmdb.cpp
index 2695d83f8..1e7078c67 100644
--- a/src/blockchain_db/lmdb/db_lmdb.cpp
+++ b/src/blockchain_db/lmdb/db_lmdb.cpp
@@ -747,7 +747,7 @@ void BlockchainLMDB::remove_output(const uint64_t& out_index, const uint64_t amo
 
   auto result = mdb_del(*m_write_txn, m_output_gindices, &k, NULL);
   if (result != 0 && result != MDB_NOTFOUND)
-      throw1(DB_ERROR("Error adding removal of output global index to db transaction"));
+      throw1(OUTPUT_DNE("Error adding removal of output global index to db transaction"));
 
   result = mdb_del(*m_write_txn, m_outputs, &v, NULL);
   if (result != 0 && result != MDB_NOTFOUND)
@@ -1242,7 +1242,7 @@ block BlockchainLMDB::get_block_from_height(const uint64_t& height) const
   auto get_result = mdb_get(txn, m_blocks, &key, &result);
   if (get_result == MDB_NOTFOUND)
   {
-    throw0(DB_ERROR(std::string("Attempt to get block from height ").append(boost::lexical_cast<std::string>(height)).append(" failed -- block not in db").c_str()));
+    throw0(BLOCK_DNE(std::string("Attempt to get block from height ").append(boost::lexical_cast<std::string>(height)).append(" failed -- block not in db").c_str()));
   }
   else if (get_result)
     throw0(DB_ERROR("Error attempting to retrieve a block from the db"));
@@ -1278,7 +1278,7 @@ uint64_t BlockchainLMDB::get_block_timestamp(const uint64_t& height) const
   auto get_result = mdb_get(*txn_ptr, m_block_timestamps, &key, &result);
   if (get_result == MDB_NOTFOUND)
   {
-    throw0(DB_ERROR(std::string("Attempt to get timestamp from height ").append(boost::lexical_cast<std::string>(height)).append(" failed -- timestamp not in db").c_str()));
+    throw0(BLOCK_DNE(std::string("Attempt to get timestamp from height ").append(boost::lexical_cast<std::string>(height)).append(" failed -- timestamp not in db").c_str()));
   }
   else if (get_result)
     throw0(DB_ERROR("Error attempting to retrieve a timestamp from the db"));
@@ -1322,7 +1322,7 @@ size_t BlockchainLMDB::get_block_size(const uint64_t& height) const
   auto get_result = mdb_get(*txn_ptr, m_block_sizes, &key, &result);
   if (get_result == MDB_NOTFOUND)
   {
-    throw0(DB_ERROR(std::string("Attempt to get block size from height ").append(boost::lexical_cast<std::string>(height)).append(" failed -- block size not in db").c_str()));
+    throw0(BLOCK_DNE(std::string("Attempt to get block size from height ").append(boost::lexical_cast<std::string>(height)).append(" failed -- block size not in db").c_str()));
   }
   else if (get_result)
     throw0(DB_ERROR("Error attempting to retrieve a block size from the db"));
@@ -1351,7 +1351,7 @@ difficulty_type BlockchainLMDB::get_block_cumulative_difficulty(const uint64_t&
   auto get_result = mdb_get(*txn_ptr, m_block_diffs, &key, &result);
   if (get_result == MDB_NOTFOUND)
   {
-    throw0(DB_ERROR(std::string("Attempt to get cumulative difficulty from height ").append(boost::lexical_cast<std::string>(height)).append(" failed -- difficulty not in db").c_str()));
+    throw0(BLOCK_DNE(std::string("Attempt to get cumulative difficulty from height ").append(boost::lexical_cast<std::string>(height)).append(" failed -- difficulty not in db").c_str()));
   }
   else if (get_result)
     throw0(DB_ERROR("Error attempting to retrieve a cumulative difficulty from the db"));
@@ -1398,7 +1398,7 @@ uint64_t BlockchainLMDB::get_block_already_generated_coins(const uint64_t& heigh
   auto get_result = mdb_get(*txn_ptr, m_block_coins, &key, &result);
   if (get_result == MDB_NOTFOUND)
   {
-    throw0(DB_ERROR(std::string("Attempt to get generated coins from height ").append(boost::lexical_cast<std::string>(height)).append(" failed -- block size not in db").c_str()));
+    throw0(BLOCK_DNE(std::string("Attempt to get generated coins from height ").append(boost::lexical_cast<std::string>(height)).append(" failed -- block size not in db").c_str()));
   }
   else if (get_result)
     throw0(DB_ERROR("Error attempting to retrieve a total generated coins from the db"));
@@ -1696,7 +1696,7 @@ output_data_t BlockchainLMDB::get_output_key(const uint64_t &global_index) const
   MDB_val v;
   auto get_result = mdb_get(txn, m_output_keys, &k, &v);
   if (get_result == MDB_NOTFOUND)
-    throw0(DB_ERROR("Attempting to get output pubkey by global index, but key does not exist"));
+    throw1(OUTPUT_DNE("Attempting to get output pubkey by global index, but key does not exist"));
   else if (get_result)
     throw0(DB_ERROR("Error attempting to retrieve an output pubkey from the db"));
 	txn.commit();
@@ -1968,6 +1968,165 @@ bool BlockchainLMDB::has_key_image(const crypto::key_image& img) const
   return false;
 }
 
+bool BlockchainLMDB::for_all_key_images(std::function<bool(const crypto::key_image&)> f) const
+{
+  LOG_PRINT_L3("BlockchainLMDB::" << __func__);
+  check_open();
+
+  mdb_txn_safe txn;
+  if (mdb_txn_begin(m_env, NULL, MDB_RDONLY, txn))
+    throw0(DB_ERROR("Failed to create a transaction for the db"));
+
+  MDB_val k;
+  MDB_val v;
+  bool ret = true;
+
+  lmdb_cur cur(txn, m_spent_keys);
+  MDB_cursor_op op = MDB_FIRST;
+  while (1)
+  {
+    int ret = mdb_cursor_get(cur, &k, &v, op);
+    op = MDB_NEXT;
+    if (ret == MDB_NOTFOUND)
+      break;
+    if (ret < 0)
+      throw0(DB_ERROR("Failed to enumerate key images"));
+    const crypto::key_image k_image = *(crypto::key_image*)k.mv_data;
+    if (!f(k_image)) {
+      ret = false;
+      break;
+    }
+  }
+
+  cur.close();
+  txn.commit();
+
+  return ret;
+}
+
+bool BlockchainLMDB::for_all_blocks(std::function<bool(uint64_t, const crypto::hash&, const cryptonote::block&)> f) const
+{
+  LOG_PRINT_L3("BlockchainLMDB::" << __func__);
+  check_open();
+
+  mdb_txn_safe txn;
+  if (mdb_txn_begin(m_env, NULL, MDB_RDONLY, txn))
+    throw0(DB_ERROR("Failed to create a transaction for the db"));
+
+  MDB_val k;
+  MDB_val v;
+  bool ret = true;
+
+  lmdb_cur cur(txn, m_blocks);
+  MDB_cursor_op op = MDB_FIRST;
+  while (1)
+  {
+    int ret = mdb_cursor_get(cur, &k, &v, op);
+    op = MDB_NEXT;
+    if (ret == MDB_NOTFOUND)
+      break;
+    if (ret)
+      throw0(DB_ERROR("Failed to enumerate blocks"));
+    uint64_t height = *(uint64_t*)k.mv_data;
+    blobdata bd;
+    bd.assign(reinterpret_cast<char*>(v.mv_data), v.mv_size);
+    block b;
+    if (!parse_and_validate_block_from_blob(bd, b))
+      throw0(DB_ERROR("Failed to parse block from blob retrieved from the db"));
+    crypto::hash hash;
+    if (!get_block_hash(b, hash))
+        throw0(DB_ERROR("Failed to get block hash from blob retrieved from the db"));
+    if (!f(height, hash, b)) {
+      ret = false;
+      break;
+    }
+  }
+
+  cur.close();
+  txn.commit();
+
+  return ret;
+}
+
+bool BlockchainLMDB::for_all_transactions(std::function<bool(const crypto::hash&, const cryptonote::transaction&)> f) const
+{
+  LOG_PRINT_L3("BlockchainLMDB::" << __func__);
+  check_open();
+
+  mdb_txn_safe txn;
+  if (mdb_txn_begin(m_env, NULL, MDB_RDONLY, txn))
+    throw0(DB_ERROR("Failed to create a transaction for the db"));
+
+  MDB_val k;
+  MDB_val v;
+  bool ret = true;
+
+  lmdb_cur cur(txn, m_txs);
+  MDB_cursor_op op = MDB_FIRST;
+  while (1)
+  {
+    int ret = mdb_cursor_get(cur, &k, &v, op);
+    op = MDB_NEXT;
+    if (ret == MDB_NOTFOUND)
+      break;
+    if (ret)
+      throw0(DB_ERROR("Failed to enumerate transactions"));
+    const crypto::hash hash = *(crypto::hash*)k.mv_data;
+    blobdata bd;
+    bd.assign(reinterpret_cast<char*>(v.mv_data), v.mv_size);
+    transaction tx;
+    if (!parse_and_validate_tx_from_blob(bd, tx))
+      throw0(DB_ERROR("Failed to parse tx from blob retrieved from the db"));
+    if (!f(hash, tx)) {
+      ret = false;
+      break;
+    }
+  }
+
+  cur.close();
+  txn.commit();
+
+  return ret;
+}
+
+bool BlockchainLMDB::for_all_outputs(std::function<bool(uint64_t amount, const crypto::hash &tx_hash, size_t tx_idx)> f) const
+{
+  LOG_PRINT_L3("BlockchainLMDB::" << __func__);
+  check_open();
+
+  mdb_txn_safe txn;
+  if (mdb_txn_begin(m_env, NULL, MDB_RDONLY, txn))
+    throw0(DB_ERROR("Failed to create a transaction for the db"));
+
+  MDB_val k;
+  MDB_val v;
+  bool ret = true;
+
+  lmdb_cur cur(txn, m_output_amounts);
+  MDB_cursor_op op = MDB_FIRST;
+  while (1)
+  {
+    int ret = mdb_cursor_get(cur, &k, &v, op);
+    op = MDB_NEXT;
+    if (ret == MDB_NOTFOUND)
+      break;
+    if (ret)
+      throw0(DB_ERROR("Failed to enumerate outputs"));
+    uint64_t amount = *(uint64_t*)k.mv_data;
+    uint64_t global_index = *(uint64_t*)v.mv_data;
+    tx_out_index toi = get_output_tx_and_index_from_global(global_index);
+    if (!f(amount, toi.first, toi.second)) {
+      ret = false;
+      break;
+    }
+  }
+
+  cur.close();
+  txn.commit();
+
+  return ret;
+}
+
 // batch_num_blocks: (optional) Used to check if resize needed before batch transaction starts.
 void BlockchainLMDB::batch_start(uint64_t batch_num_blocks)
 {
@@ -2329,8 +2488,8 @@ void BlockchainLMDB::get_output_key(const uint64_t &amount, const std::vector<ui
 			MDB_val v;
 
 			auto get_result = mdb_get(*txn_ptr, m_output_keys, &k, &v);
-			if (get_result != 0)
-				throw0(DB_ERROR("Attempting to get output pubkey by global index, but key does not exist"));
+			if (get_result == MDB_NOTFOUND)
+				throw1(OUTPUT_DNE("Attempting to get output pubkey by global index, but key does not exist"));
 			else if (get_result)
 				throw0(DB_ERROR("Error attempting to retrieve an output pubkey from the db"));
 
diff --git a/src/blockchain_db/lmdb/db_lmdb.h b/src/blockchain_db/lmdb/db_lmdb.h
index 380954295..6125ef2ef 100644
--- a/src/blockchain_db/lmdb/db_lmdb.h
+++ b/src/blockchain_db/lmdb/db_lmdb.h
@@ -189,6 +189,11 @@ public:
 
   virtual bool has_key_image(const crypto::key_image& img) const;
 
+  virtual bool for_all_key_images(std::function<bool(const crypto::key_image&)>) const;
+  virtual bool for_all_blocks(std::function<bool(uint64_t, const crypto::hash&, const cryptonote::block&)>) const;
+  virtual bool for_all_transactions(std::function<bool(const crypto::hash&, const cryptonote::transaction&)>) const;
+  virtual bool for_all_outputs(std::function<bool(uint64_t amount, const crypto::hash &tx_hash, size_t tx_idx)> f) const;
+
   virtual uint64_t add_block( const block& blk
                             , const size_t& block_size
                             , const difficulty_type& cumulative_difficulty
diff --git a/src/blockchain_utilities/CMakeLists.txt b/src/blockchain_utilities/CMakeLists.txt
index 7be9d95f7..f88180686 100644
--- a/src/blockchain_utilities/CMakeLists.txt
+++ b/src/blockchain_utilities/CMakeLists.txt
@@ -67,6 +67,15 @@ bitmonero_private_headers(blockchain_export
 	  ${blockchain_export_private_headers})
 
 
+set(blockchain_dump_sources
+  blockchain_dump.cpp
+  )
+
+set(blockchain_dump_private_headers)
+
+bitmonero_private_headers(blockchain_dump
+	  ${blockchain_dump_private_headers})
+
 
 if (BLOCKCHAIN_DB STREQUAL DB_LMDB)
 bitmonero_add_executable(blockchain_converter
@@ -120,3 +129,21 @@ add_dependencies(blockchain_export
 set_property(TARGET blockchain_export
 	PROPERTY
 	OUTPUT_NAME "blockchain_export")
+
+bitmonero_add_executable(blockchain_dump
+  ${blockchain_dump_sources}
+  ${blockchain_dump_private_headers})
+
+target_link_libraries(blockchain_dump
+  LINK_PRIVATE
+    cryptonote_core
+	blockchain_db
+	p2p
+    ${CMAKE_THREAD_LIBS_INIT})
+
+add_dependencies(blockchain_dump
+	version)
+set_property(TARGET blockchain_dump
+	PROPERTY
+	OUTPUT_NAME "blockchain_dump")
+
diff --git a/src/blockchain_utilities/blockchain_dump.cpp b/src/blockchain_utilities/blockchain_dump.cpp
new file mode 100644
index 000000000..4c3c09c43
--- /dev/null
+++ b/src/blockchain_utilities/blockchain_dump.cpp
@@ -0,0 +1,431 @@
+// Copyright (c) 2014-2015, The Monero Project
+//
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without modification, are
+// permitted provided that the following conditions are met:
+//
+// 1. Redistributions of source code must retain the above copyright notice, this list of
+//    conditions and the following disclaimer.
+//
+// 2. Redistributions in binary form must reproduce the above copyright notice, this list
+//    of conditions and the following disclaimer in the documentation and/or other
+//    materials provided with the distribution.
+//
+// 3. Neither the name of the copyright holder nor the names of its contributors may be
+//    used to endorse or promote products derived from this software without specific
+//    prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
+// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
+// THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
+// THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#include "cryptonote_core/cryptonote_basic.h"
+#include "cryptonote_core/blockchain_storage.h"
+#include "cryptonote_core/blockchain.h"
+#include "blockchain_db/blockchain_db.h"
+#include "blockchain_db/lmdb/db_lmdb.h"
+#include "blockchain_db/berkeleydb/db_bdb.h"
+#include "blockchain_utilities.h"
+#include "common/command_line.h"
+#include "version.h"
+
+unsigned int epee::g_test_dbg_lock_sleep = 0;
+
+namespace po = boost::program_options;
+using namespace epee; // log_space
+
+using namespace cryptonote;
+
+struct DumpContext {
+  std::ofstream &f;
+  size_t level;
+  std::vector<std::string> close;
+
+  DumpContext(std::ofstream &f): f(f), level(0) {}
+};
+
+template<typename S> static void start_compound(DumpContext &d, S key, bool array, bool print = false)
+{
+  if (print)
+    LOG_PRINT_L0("Dumping " << key << "...");
+  d.f << std::string(d.level*2, ' ');
+  d.f << "\"" << key << "\": " << (array ? "[" : "{") << " \n";
+  d.close.push_back(array ? "]" : "}");
+  d.level++;
+}
+
+template<typename S> static void start_array(DumpContext &d, S key, bool print = false) { start_compound(d, key, true, print); }
+template<typename S> static void start_struct(DumpContext &d, S key, bool print = false) { start_compound(d, key, false, print); }
+
+static void end_compound(DumpContext &d)
+{
+  d.level--;
+  d.f << std::string(d.level*2, ' ');
+  d.f << d.close.back() << ",\n";
+  d.close.pop_back();
+}
+
+template<typename S, typename T> static void write_pod(DumpContext &d, S key, const T &t)
+{
+  d.f << std::string(d.level*2, ' ');
+  d.f << "\"" << key << "\": ";
+  d.f << t;
+  d.f << ",\n";
+}
+
+template<typename T> static void write_pod(DumpContext &d, const T &t)
+{
+  d.f << std::string(d.level*2, ' ');
+  d.f << t;
+  d.f << ",\n";
+}
+
+int main(int argc, char* argv[])
+{
+  uint32_t log_level = 0;
+  uint64_t block_stop = 0;
+
+  boost::filesystem::path default_data_path {tools::get_default_data_dir()};
+  boost::filesystem::path default_testnet_data_path {default_data_path / "testnet"};
+  boost::filesystem::path output_file_path;
+
+  po::options_description desc_cmd_only("Command line options");
+  po::options_description desc_cmd_sett("Command line options and settings options");
+  const command_line::arg_descriptor<std::string> arg_output_file = {"output-file", "Specify output file", "", true};
+  const command_line::arg_descriptor<uint32_t> arg_log_level  = {"log-level",  "", log_level};
+  const command_line::arg_descriptor<uint64_t> arg_block_stop = {"block-stop", "Stop at block number", block_stop};
+#if SOURCE_DB != DB_MEMORY
+  const command_line::arg_descriptor<std::string> arg_db_type = {
+    "db-type"
+  , "Specify database type"
+  , DEFAULT_DB_TYPE
+  };
+  const command_line::arg_descriptor<bool>     arg_include_db_only_data = {
+    "include-db-only-data"
+      , "Include data that is only in a database version."
+      , false
+  };
+#endif
+  const command_line::arg_descriptor<bool>     arg_testnet_on = {
+    "testnet"
+      , "Run on testnet."
+      , false
+  };
+
+
+  command_line::add_arg(desc_cmd_sett, command_line::arg_data_dir, default_data_path.string());
+  command_line::add_arg(desc_cmd_sett, command_line::arg_testnet_data_dir, default_testnet_data_path.string());
+  command_line::add_arg(desc_cmd_sett, arg_output_file);
+#if SOURCE_DB != DB_MEMORY
+  command_line::add_arg(desc_cmd_sett, arg_db_type);
+  command_line::add_arg(desc_cmd_sett, arg_include_db_only_data);
+#endif
+  command_line::add_arg(desc_cmd_sett, arg_testnet_on);
+  command_line::add_arg(desc_cmd_sett, arg_log_level);
+  command_line::add_arg(desc_cmd_sett, arg_block_stop);
+
+  command_line::add_arg(desc_cmd_only, command_line::arg_help);
+
+  po::options_description desc_options("Allowed options");
+  desc_options.add(desc_cmd_only).add(desc_cmd_sett);
+
+  po::variables_map vm;
+  bool r = command_line::handle_error_helper(desc_options, [&]()
+  {
+    po::store(po::parse_command_line(argc, argv, desc_options), vm);
+    po::notify(vm);
+    return true;
+  });
+  if (! r)
+    return 1;
+
+  if (command_line::get_arg(vm, command_line::arg_help))
+  {
+    std::cout << CRYPTONOTE_NAME << " v" << MONERO_VERSION_FULL << ENDL << ENDL;
+    std::cout << desc_options << std::endl;
+    return 1;
+  }
+
+  log_level    = command_line::get_arg(vm, arg_log_level);
+  block_stop = command_line::get_arg(vm, arg_block_stop);
+
+  log_space::get_set_log_detalisation_level(true, log_level);
+  log_space::log_singletone::add_logger(LOGGER_CONSOLE, NULL, NULL);
+  LOG_PRINT_L0("Starting...");
+  LOG_PRINT_L0("Setting log level = " << log_level);
+
+  bool opt_testnet = command_line::get_arg(vm, arg_testnet_on);
+  bool opt_include_db_only_data = command_line::get_arg(vm, arg_include_db_only_data);
+
+  std::string m_config_folder;
+
+  auto data_dir_arg = opt_testnet ? command_line::arg_testnet_data_dir : command_line::arg_data_dir;
+  m_config_folder = command_line::get_arg(vm, data_dir_arg);
+
+  if (command_line::has_arg(vm, arg_output_file))
+    output_file_path = boost::filesystem::path(command_line::get_arg(vm, arg_output_file));
+  else
+    output_file_path = boost::filesystem::path(m_config_folder) / "dump" / "blockchain.json";
+  LOG_PRINT_L0("Export output file: " << output_file_path.string());
+
+  const boost::filesystem::path dir_path = output_file_path.parent_path();
+  if (!dir_path.empty())
+  {
+    if (boost::filesystem::exists(dir_path))
+    {
+      if (!boost::filesystem::is_directory(dir_path))
+      {
+        LOG_PRINT_RED_L0("dump directory path is a file: " << dir_path);
+        return false;
+      }
+    }
+    else
+    {
+      if (!boost::filesystem::create_directory(dir_path))
+      {
+        LOG_PRINT_RED_L0("Failed to create directory " << dir_path);
+        return false;
+      }
+    }
+  }
+
+  std::ofstream raw_data_file;
+  raw_data_file.open(output_file_path.string(), std::ios_base::out | std::ios::trunc);
+  if (raw_data_file.fail())
+    return false;
+
+
+  // If we wanted to use the memory pool, we would set up a fake_core.
+
+#if SOURCE_DB == DB_MEMORY
+  // blockchain_storage* core_storage = NULL;
+  // tx_memory_pool m_mempool(*core_storage); // is this fake anyway? just passing in NULL! so m_mempool can't be used anyway, right?
+  // core_storage = new blockchain_storage(&m_mempool);
+
+  blockchain_storage* core_storage = new blockchain_storage(NULL);
+  LOG_PRINT_L0("Initializing source blockchain (in-memory database)");
+  r = core_storage->init(m_config_folder, opt_testnet);
+#else
+  // Use Blockchain instead of lower-level BlockchainDB for two reasons:
+  // 1. Blockchain has the init() method for easy setup
+  // 2. exporter needs to use get_current_blockchain_height(), get_block_id_by_height(), get_block_by_hash()
+  //
+  // cannot match blockchain_storage setup above with just one line,
+  // e.g.
+  //   Blockchain* core_storage = new Blockchain(NULL);
+  // because unlike blockchain_storage constructor, which takes a pointer to
+  // tx_memory_pool, Blockchain's constructor takes tx_memory_pool object.
+  LOG_PRINT_L0("Initializing source blockchain (BlockchainDB)");
+  Blockchain *core_storage = NULL;
+  tx_memory_pool m_mempool(*core_storage);
+  core_storage = new Blockchain(m_mempool);
+
+  BlockchainDB* db;
+  int mdb_flags = 0;
+  std::string db_type = command_line::get_arg(vm, arg_db_type);
+  if (db_type.empty() || db_type == "lmdb")
+  {
+    db = new BlockchainLMDB();
+    mdb_flags |= MDB_RDONLY;
+  }
+  else if (db_type == "berkeley")
+  {
+    db = new BlockchainBDB();
+    // can't open readonly due to the way flags are split in db_bdb.cpp
+  }
+  else
+  {
+    LOG_PRINT_L0("Invalid db type: " << db_type);
+    throw;
+  }
+  boost::filesystem::path folder(m_config_folder);
+  folder /= db->get_db_name();
+  const std::string filename = folder.string();
+
+  LOG_PRINT_L0("Loading blockchain from folder " << filename << " ...");
+  try
+  {
+    db->open(filename, mdb_flags);
+  }
+  catch (const std::exception& e)
+  {
+    LOG_PRINT_L0("Error opening database: " << e.what());
+    throw;
+  }
+  r = core_storage->init(db, opt_testnet);
+#endif
+
+  CHECK_AND_ASSERT_MES(r, false, "Failed to initialize source blockchain storage");
+  LOG_PRINT_L0("Source blockchain storage initialized OK");
+  LOG_PRINT_L0("Dumping blockchain...");
+
+  DumpContext d(raw_data_file);
+
+  start_struct(d,"blockchain");
+    uint64_t height = core_storage->get_current_blockchain_height();
+    write_pod(d, "height", height);
+goto start;
+    start_array(d,"blockids", true);
+      for (uint64_t h = 0; h < height; ++h)
+        write_pod(d,core_storage->get_block_id_by_height(h));
+    end_compound(d);
+    start_array(d,"txids", true);
+    {
+      std::vector<crypto::hash> txids;
+      core_storage->for_all_transactions([&txids](const crypto::hash &hash, const cryptonote::transaction &tx)->bool{txids.push_back(hash); return true;});
+      std::sort(txids.begin(), txids.end(),
+        [](const crypto::hash &txid0, const crypto::hash &txid1) {return memcmp(txid0.data, txid1.data, sizeof(crypto::hash::data)) < 0;});
+      for (size_t n = 0; n < txids.size(); ++n)
+        write_pod(d, txids[n]);
+    }
+    end_compound(d);
+    start_struct(d,"transactions", true);
+    {
+      for (uint64_t h = 0; h < height; ++h)
+      {
+        start_array(d, boost::lexical_cast<std::string>(h));
+          std::list<cryptonote::block> blocks;
+          std::list<cryptonote::transaction> transactions, miner_tx;
+          core_storage->get_blocks(h, 1, blocks, transactions);
+          if (blocks.size() != 1)
+            throw std::string("Expected 1 block at height ") + boost::lexical_cast<std::string>(h);
+          crypto::hash txid = cryptonote::get_transaction_hash(blocks.front().miner_tx);
+          write_pod(d, string_tools::pod_to_hex(txid).c_str(), obj_to_json_str(blocks.front().miner_tx));
+          std::vector<std::pair<crypto::hash, cryptonote::transaction>> txes;
+          for (std::list<cryptonote::transaction>::iterator i = transactions.begin(); i != transactions.end(); ++i)
+            txes.push_back(std::make_pair(cryptonote::get_transaction_hash(*i), *i));
+          std::sort(txes.begin(), txes.end(),
+            [](const std::pair<crypto::hash, cryptonote::transaction> &tx0, const std::pair<crypto::hash, cryptonote::transaction> &tx1) {return memcmp(tx0.first.data, tx1.first.data, sizeof(crypto::key_image::data)) < 0;});
+          for (std::vector<std::pair<crypto::hash, cryptonote::transaction>>::iterator i = txes.begin(); i != txes.end(); ++i)
+          {
+            write_pod(d, string_tools::pod_to_hex((*i).first).c_str(), obj_to_json_str((*i).second));
+          }
+        end_compound(d);
+      }
+    }
+    start_struct(d,"blocks", true);
+    {
+      std::vector<crypto::hash> blockids;
+      core_storage->for_all_blocks([&](uint64_t height, const crypto::hash &hash, const cryptonote::block &b)->bool{
+         start_struct(d, boost::lexical_cast<std::string>(height));
+           write_pod(d, "hash", string_tools::pod_to_hex(hash));
+           cryptonote::block block = b;
+           write_pod(d, "block", obj_to_json_str(block));
+         end_compound(d);
+         return true;
+      });
+    }
+    end_compound(d);
+    start_array(d,"key_images", true);
+    {
+      std::vector<crypto::key_image> key_images;
+      core_storage->for_all_key_images([&key_images](const crypto::key_image &k_image)->bool{key_images.push_back(k_image); return true;});
+      std::sort(key_images.begin(), key_images.end(),
+        [](const crypto::key_image &k0, const crypto::key_image &k1) {return memcmp(k0.data, k1.data, sizeof(crypto::key_image::data)) < 0;});
+      for (size_t n = 0; n < key_images.size(); ++n)
+        write_pod(d,key_images[n]);
+    }
+    end_compound(d);
+    if (opt_include_db_only_data)
+    {
+      start_struct(d, "block_timestamps", true);
+        for (uint64_t h = 0; h < height; ++h)
+          write_pod(d,boost::lexical_cast<std::string>(h),db->get_block_timestamp(h));
+      end_compound(d);
+      start_struct(d, "block_difficulties", true);
+        for (uint64_t h = 0; h < height; ++h)
+          write_pod(d,boost::lexical_cast<std::string>(h),db->get_block_cumulative_difficulty(h));
+      end_compound(d);
+      start_struct(d, "block_sizes", true);
+        for (uint64_t h = 0; h < height; ++h)
+          write_pod(d,boost::lexical_cast<std::string>(h),db->get_block_size(h));
+      end_compound(d);
+      start_struct(d, "block_coins", true);
+        for (uint64_t h = 0; h < height; ++h)
+          write_pod(d,boost::lexical_cast<std::string>(h),db->get_block_already_generated_coins(h));
+      end_compound(d);
+      start_struct(d, "block_heights", true);
+        for (uint64_t h = 0; h < height; ++h)
+        {
+          const crypto::hash hash = core_storage->get_block_id_by_height(h);
+          write_pod(d,boost::lexical_cast<std::string>(h),db->get_block_height(hash));
+        }
+      end_compound(d);
+      {
+        std::vector<crypto::hash> txids;
+        core_storage->for_all_transactions([&txids](const crypto::hash &hash, const cryptonote::transaction &tx)->bool{txids.push_back(hash); return true;});
+        std::sort(txids.begin(), txids.end(),
+          [](const crypto::hash &txid0, const crypto::hash &txid1) {return memcmp(txid0.data, txid1.data, sizeof(crypto::hash::data)) < 0;});
+        start_struct(d, "transaction_unlock_times", true);
+          for (size_t n = 0; n < txids.size(); ++n)
+            write_pod(d,string_tools::pod_to_hex(txids[n]),db->get_tx_unlock_time(txids[n]));
+        end_compound(d);
+        start_struct(d, "transaction_block_heights", true);
+          for (size_t n = 0; n < txids.size(); ++n)
+            write_pod(d,string_tools::pod_to_hex(txids[n]),db->get_tx_block_height(txids[n]));
+        end_compound(d);
+      }
+      start_array(d, "tx_and_index_from_global", true);
+        for (uint64_t idx = 0; ; ++idx)
+        {
+          try
+          {
+            tx_out_index toi = db->get_output_tx_and_index_from_global(idx);
+            start_struct(d, boost::lexical_cast<std::string>(idx));
+              write_pod(d, "tx_hash", string_tools::pod_to_hex(toi.first));
+              write_pod(d, "tx_index", string_tools::pod_to_hex(toi.second));
+            end_compound(d);
+          }
+          catch (const OUTPUT_DNE &) { break; }
+        }
+      end_compound(d);
+start:
+      start_struct(d, "outputs_amounts", true);
+        for (uint64_t base = 1; base <= (uint64_t)10000000000000000000ul; base *= 10) for (uint64_t digit = 1; digit <= 9; ++digit) {
+          uint64_t amount = digit * base;
+          write_pod(d, boost::lexical_cast<std::string>(amount), db->get_num_outputs(amount));
+        }
+      end_compound(d);
+      start_array(d, "output_keys", true);
+        for (uint64_t idx = 0; ; ++idx)
+        {
+          try
+          {
+            output_data_t od = db->get_output_key(idx);
+            start_struct(d, boost::lexical_cast<std::string>(idx));
+              write_pod(d, "pubkey", string_tools::pod_to_hex(od.pubkey));
+              write_pod(d, "unlock_time", od.unlock_time);
+              write_pod(d, "height", od.height);
+            end_compound(d);
+          }
+          catch (const OUTPUT_DNE &) { break; }
+        }
+      end_compound(d);
+      start_struct(d, "hf_versions", true);
+        for (uint64_t h = 0; h < height; ++h)
+          write_pod(d, boost::lexical_cast<std::string>(h), (unsigned int)db->get_hard_fork_version(h));
+      end_compound(d);
+      start_struct(d, "hf_starting_heights", true);
+        for (unsigned int v = 0; v <= 255; ++v)
+          write_pod(d, boost::lexical_cast<std::string>(v), db->get_hard_fork_starting_height(v));
+      end_compound(d);
+    }
+  end_compound(d);
+
+  CHECK_AND_ASSERT_MES(r, false, "Failed to dump blockchain");
+
+  if (raw_data_file.fail())
+    return false;
+  raw_data_file.flush();
+
+  LOG_PRINT_L0("Blockchain dump OK");
+
+  return 0;
+}
diff --git a/src/cryptonote_core/blockchain.cpp b/src/cryptonote_core/blockchain.cpp
index 306530f02..99d654bb1 100644
--- a/src/cryptonote_core/blockchain.cpp
+++ b/src/cryptonote_core/blockchain.cpp
@@ -3188,3 +3188,23 @@ bool Blockchain::get_hard_fork_voting_info(uint8_t version, uint32_t &window, ui
 {
     return m_hardfork->get_voting_info(version, window, votes, threshold, voting);
 }
+
+bool Blockchain::for_all_key_images(std::function<bool(const crypto::key_image&)> f) const
+{
+  return m_db->for_all_key_images(f);
+}
+
+bool Blockchain::for_all_blocks(std::function<bool(uint64_t, const crypto::hash&, const block&)> f) const
+{
+  return m_db->for_all_blocks(f);
+}
+
+bool Blockchain::for_all_transactions(std::function<bool(const crypto::hash&, const cryptonote::transaction&)> f) const
+{
+  return m_db->for_all_transactions(f);
+}
+
+bool Blockchain::for_all_outputs(std::function<bool(uint64_t amount, const crypto::hash &tx_hash, size_t tx_idx)> f) const
+{
+  return m_db->for_all_outputs(f);;
+}
diff --git a/src/cryptonote_core/blockchain.h b/src/cryptonote_core/blockchain.h
index 3a663a342..21bbfb447 100644
--- a/src/cryptonote_core/blockchain.h
+++ b/src/cryptonote_core/blockchain.h
@@ -165,6 +165,11 @@ namespace cryptonote
     uint8_t get_ideal_hard_fork_version() const { return m_hardfork->get_ideal_version(); }
     bool get_hard_fork_voting_info(uint8_t version, uint32_t &window, uint32_t &votes, uint32_t &threshold, uint8_t &voting) const;
 
+    bool for_all_key_images(std::function<bool(const crypto::key_image&)>) const;
+    bool for_all_blocks(std::function<bool(uint64_t, const crypto::hash&, const block&)>) const;
+    bool for_all_transactions(std::function<bool(const crypto::hash&, const cryptonote::transaction&)>) const;
+    bool for_all_outputs(std::function<bool(uint64_t amount, const crypto::hash &tx_hash, size_t tx_idx)>) const;
+
     BlockchainDB& get_db()
     {
       return *m_db;
diff --git a/src/cryptonote_core/blockchain_storage.cpp b/src/cryptonote_core/blockchain_storage.cpp
index 4a4d348ba..16aaf7079 100644
--- a/src/cryptonote_core/blockchain_storage.cpp
+++ b/src/cryptonote_core/blockchain_storage.cpp
@@ -1890,3 +1890,41 @@ void blockchain_storage::set_enforce_dns_checkpoints(bool enforce_checkpoints)
 {
   m_enforce_dns_checkpoints = enforce_checkpoints;
 }
+//------------------------------------------------------------------
+bool blockchain_storage::for_all_key_images(std::function<bool(const crypto::key_image&)> f) const
+{
+  for (key_images_container::const_iterator i = m_spent_keys.begin(); i != m_spent_keys.end(); ++i) {
+    if (!f(*i))
+      return false;
+  }
+  return true;
+}
+//------------------------------------------------------------------
+bool blockchain_storage::for_all_blocks(std::function<bool(uint64_t, const block&)> f) const
+{
+  for (blocks_container::const_iterator i = m_blocks.begin(); i != m_blocks.end(); ++i) {
+    if (!f(i->height, i->bl))
+      return false;
+  }
+  return true;
+}
+//------------------------------------------------------------------
+bool blockchain_storage::for_all_transactions(std::function<bool(const transaction&)> f) const
+{
+  for (transactions_container::const_iterator i = m_transactions.begin(); i != m_transactions.end(); ++i) {
+    if (!f(i->second.tx))
+      return false;
+  }
+  return true;
+}
+//------------------------------------------------------------------
+bool blockchain_storage::for_all_outputs(std::function<bool(uint64_t, const crypto::hash&, size_t)> f) const
+{
+  for (outputs_container::const_iterator i = m_outputs.begin(); i != m_outputs.end(); ++i) {
+    for (size_t n = 0; n < i->second.size(); ++n) {
+      if (!f(i->first, i->second[n].first, i->second[n].second))
+        return false;
+    }
+  }
+  return true;
+}
diff --git a/src/cryptonote_core/blockchain_storage.h b/src/cryptonote_core/blockchain_storage.h
index 2a4cfcd49..4a4fc14c2 100644
--- a/src/cryptonote_core/blockchain_storage.h
+++ b/src/cryptonote_core/blockchain_storage.h
@@ -185,6 +185,11 @@ namespace cryptonote
     difficulty_type get_block_cumulative_difficulty(uint64_t height) const { return m_blocks[height].cumulative_difficulty; }
     uint64_t get_block_coins_generated(uint64_t height) const { return m_blocks[height].already_generated_coins; }
 
+    bool for_all_key_images(std::function<bool(const crypto::key_image&)>) const;
+    bool for_all_blocks(std::function<bool(uint64_t height, const block&)>) const;
+    bool for_all_transactions(std::function<bool(const transaction&)>) const;
+    bool for_all_outputs(std::function<bool(uint64_t amount, const crypto::hash &tx_hash, size_t tx_idx)>) const;
+
     // use for testing only
     bool debug_pop_block_from_blockchain() { return pop_block_from_blockchain(); }