New add_aux_pow RPC to support merge mining

12 files changed, 494 insertions, 1 deletions

diff --git a/src/crypto/hash-ops.h b/src/crypto/hash-ops.h
index 7dfc5151d..1cd502994 100644
--- a/src/crypto/hash-ops.h
+++ b/src/crypto/hash-ops.h
@@ -87,6 +87,10 @@ void hash_extra_jh(const void *data, size_t length, char *hash);
 void hash_extra_skein(const void *data, size_t length, char *hash);
 
 void tree_hash(const char (*hashes)[HASH_SIZE], size_t count, char *root_hash);
+bool tree_path(size_t count, size_t idx, uint32_t *path);
+bool tree_branch(const char (*hashes)[HASH_SIZE], size_t count, const char *hash, char (*branch)[HASH_SIZE], size_t *depth, uint32_t *path);
+bool tree_branch_hash(const char hash[HASH_SIZE], const char (*branch)[HASH_SIZE], size_t depth, uint32_t path, char root[HASH_SIZE]);
+bool is_branch_in_tree(const char hash[HASH_SIZE], const char root[HASH_SIZE], const char (*branch)[HASH_SIZE], size_t depth, uint32_t path);
 
 #define RX_BLOCK_VERSION	12
 void rx_slow_hash_allocate_state(void);
diff --git a/src/crypto/tree-hash.c b/src/crypto/tree-hash.c
index 643e95121..8f3ea3339 100644
--- a/src/crypto/tree-hash.c
+++ b/src/crypto/tree-hash.c
@@ -104,3 +104,154 @@ void tree_hash(const char (*hashes)[HASH_SIZE], size_t count, char *root_hash) {
     free(ints);
   }
 }
+
+bool tree_path(size_t count, size_t idx, uint32_t *path)
+{
+  if (count == 0)
+    return false;
+
+  if (count == 1) {
+    *path = 0;
+  } else if (count == 2) {
+    *path = idx == 0 ? 0 : 1;
+  } else {
+    size_t i, j;
+
+    *path = 0;
+    size_t cnt = tree_hash_cnt( count );
+
+    for (i = 2 * cnt - count, j = 2 * cnt - count; j < cnt; i += 2, ++j) {
+      if (idx == i || idx == i+1)
+      {
+        *path = (*path << 1) | (idx == i ? 0 : 1);
+        idx = j;
+      }
+    }
+    assert(i == count);
+
+    while (cnt > 2) {
+      cnt >>= 1;
+      for (i = 0, j = 0; j < cnt; i += 2, ++j) {
+        if (idx == i || idx == i + 1)
+        {
+          *path = (*path << 1) | (idx == i ? 0 : 1);
+          idx = j;
+        }
+      }
+    }
+
+    if (idx == 0 || idx == 1)
+    {
+      *path = (*path << 1) | (idx == 0 ? 0 : 1);
+      idx = 0;
+    }
+  }
+  return true;
+}
+
+bool tree_branch(const char (*hashes)[HASH_SIZE], size_t count, const char *hash, char (*branch)[HASH_SIZE], size_t *depth, uint32_t *path)
+{
+  size_t idx;
+
+  if (count == 0)
+    return false;
+
+  for (idx = 0; idx < count; ++idx)
+    if (!memcmp(hash, hashes[idx], HASH_SIZE))
+      break;
+  if (idx == count)
+    return false;
+
+  assert(count > 0);
+  if (count == 1) {
+    *depth = 0;
+    *path = 0;
+  } else if (count == 2) {
+    *depth = 1;
+    *path = idx == 0 ? 0 : 1;
+    memcpy(branch[0], hashes[idx ^ 1], HASH_SIZE);
+  } else {
+    size_t i, j;
+
+    *depth = 0;
+    *path = 0;
+    size_t cnt = tree_hash_cnt( count );
+
+    char *ints = calloc(cnt, HASH_SIZE);  // zero out as extra protection for using uninitialized mem
+    assert(ints);
+
+    memcpy(ints, hashes, (2 * cnt - count) * HASH_SIZE);
+
+    for (i = 2 * cnt - count, j = 2 * cnt - count; j < cnt; i += 2, ++j) {
+      if (idx == i || idx == i+1)
+      {
+        memcpy(branch[*depth], hashes[idx == i ? i + 1 : i], HASH_SIZE);
+        ++*depth;
+        *path = (*path << 1) | (idx == i ? 0 : 1);
+        idx = j;
+      }
+      cn_fast_hash(hashes[i], 64, ints + j * HASH_SIZE);
+    }
+    assert(i == count);
+
+    while (cnt > 2) {
+      cnt >>= 1;
+      for (i = 0, j = 0; j < cnt; i += 2, ++j) {
+        if (idx == i || idx == i + 1)
+        {
+          memcpy(branch[*depth], ints + (idx == i ? i + 1 : i) * HASH_SIZE, HASH_SIZE);
+          ++*depth;
+          *path = (*path << 1) | (idx == i ? 0 : 1);
+          idx = j;
+        }
+        cn_fast_hash(ints + i * HASH_SIZE, 64, ints + j * HASH_SIZE);
+      }
+    }
+
+    if (idx == 0 || idx == 1)
+    {
+      memcpy(branch[*depth], ints + (idx == 0 ? 1 : 0) * HASH_SIZE, HASH_SIZE);
+      ++*depth;
+      *path = (*path << 1) | (idx == 0 ? 0 : 1);
+      idx = 0;
+    }
+
+    free(ints);
+  }
+  return true;
+}
+
+bool tree_branch_hash(const char hash[HASH_SIZE], const char (*branch)[HASH_SIZE], size_t depth, uint32_t path, char root[HASH_SIZE])
+{
+  size_t d;
+  char partial[HASH_SIZE];
+
+  memcpy(partial, hash, HASH_SIZE);
+
+  for (d = 0; d < depth; ++d)
+  {
+    char buffer[2 * HASH_SIZE];
+    if ((path >> (depth - d - 1)) & 1)
+    {
+      memcpy(buffer, branch[d], HASH_SIZE);
+      memcpy(buffer + HASH_SIZE, partial, HASH_SIZE);
+    }
+    else
+    {
+      memcpy(buffer, partial, HASH_SIZE);
+      memcpy(buffer + HASH_SIZE, branch[d], HASH_SIZE);
+    }
+    cn_fast_hash(buffer, 2 * HASH_SIZE, partial);
+  }
+
+  memcpy(root, partial, HASH_SIZE);
+  return true;
+}
+
+bool is_branch_in_tree(const char hash[HASH_SIZE], const char root[HASH_SIZE], const char (*branch)[HASH_SIZE], size_t depth, uint32_t path)
+{
+  char res[HASH_SIZE];
+  if (!tree_branch_hash(hash, branch, depth, path, res))
+    return false;
+  return memcmp(res, root, HASH_SIZE) == 0;
+}
diff --git a/src/cryptonote_basic/CMakeLists.txt b/src/cryptonote_basic/CMakeLists.txt
index 5286256c7..c9fb1433c 100644
--- a/src/cryptonote_basic/CMakeLists.txt
+++ b/src/cryptonote_basic/CMakeLists.txt
@@ -43,6 +43,7 @@ set(cryptonote_basic_sources
   cryptonote_format_utils.cpp
   difficulty.cpp
   hardfork.cpp
+  merge_mining.cpp
   miner.cpp)
 
 set(cryptonote_basic_headers)
@@ -57,6 +58,7 @@ set(cryptonote_basic_private_headers
   cryptonote_format_utils.h
   difficulty.h
   hardfork.h
+  merge_mining.h
   miner.h
   tx_extra.h
   verification_context.h)
diff --git a/src/cryptonote_basic/cryptonote_format_utils.cpp b/src/cryptonote_basic/cryptonote_format_utils.cpp
index fcc96883b..259334b16 100644
--- a/src/cryptonote_basic/cryptonote_format_utils.cpp
+++ b/src/cryptonote_basic/cryptonote_format_utils.cpp
@@ -728,6 +728,25 @@ namespace cryptonote
     return true;
   }
   //---------------------------------------------------------------
+  bool add_mm_merkle_root_to_tx_extra(std::vector<uint8_t>& tx_extra, const crypto::hash& mm_merkle_root, size_t mm_merkle_tree_depth)
+  {
+    CHECK_AND_ASSERT_MES(mm_merkle_tree_depth < 32, false, "merge mining merkle tree depth should be less than 32");
+    size_t start_pos = tx_extra.size();
+    tx_extra.resize(tx_extra.size() + 3 + 32);
+    //write tag
+    tx_extra[start_pos] = TX_EXTRA_MERGE_MINING_TAG;
+    //write data size
+    ++start_pos;
+    tx_extra[start_pos] = 33;
+    //write depth varint (always one byte here)
+    ++start_pos;
+    tx_extra[start_pos] = mm_merkle_tree_depth;
+    //write data
+    ++start_pos;
+    memcpy(&tx_extra[start_pos], &mm_merkle_root, 32);
+    return true;
+  }
+  //---------------------------------------------------------------
   bool remove_field_from_tx_extra(std::vector<uint8_t>& tx_extra, const std::type_info &type)
   {
     if (tx_extra.empty())
diff --git a/src/cryptonote_basic/cryptonote_format_utils.h b/src/cryptonote_basic/cryptonote_format_utils.h
index 636a88b9a..b311bd2b2 100644
--- a/src/cryptonote_basic/cryptonote_format_utils.h
+++ b/src/cryptonote_basic/cryptonote_format_utils.h
@@ -83,6 +83,7 @@ namespace cryptonote
   std::vector<crypto::public_key> get_additional_tx_pub_keys_from_extra(const transaction_prefix& tx);
   bool add_additional_tx_pub_keys_to_extra(std::vector<uint8_t>& tx_extra, const std::vector<crypto::public_key>& additional_pub_keys);
   bool add_extra_nonce_to_tx_extra(std::vector<uint8_t>& tx_extra, const blobdata& extra_nonce);
+  bool add_mm_merkle_root_to_tx_extra(std::vector<uint8_t>& tx_extra, const crypto::hash& mm_merkle_root, size_t mm_merkle_tree_depth);
   bool remove_field_from_tx_extra(std::vector<uint8_t>& tx_extra, const std::type_info &type);
   void set_payment_id_to_tx_extra_nonce(blobdata& extra_nonce, const crypto::hash& payment_id);
   void set_encrypted_payment_id_to_tx_extra_nonce(blobdata& extra_nonce, const crypto::hash8& payment_id);
diff --git a/src/cryptonote_basic/merge_mining.cpp b/src/cryptonote_basic/merge_mining.cpp
new file mode 100644
index 000000000..fcc74859f
--- /dev/null
+++ b/src/cryptonote_basic/merge_mining.cpp
@@ -0,0 +1,95 @@
+// Copyright (c) 2020, 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 <string.h>
+#include "misc_log_ex.h"
+#include "int-util.h"
+#include "crypto/crypto.h"
+#include "common/util.h"
+#include "merge_mining.h"
+
+using namespace epee;
+
+#undef MONERO_DEFAULT_LOG_CATEGORY
+#define MONERO_DEFAULT_LOG_CATEGORY "cn.mm"
+
+using namespace crypto;
+
+namespace cryptonote
+{
+
+//---------------------------------------------------------------
+uint32_t get_aux_slot(const crypto::hash &id, uint32_t nonce, uint32_t n_aux_chains)
+{
+  CHECK_AND_ASSERT_THROW_MES(n_aux_chains > 0, "n_aux_chains is 0");
+
+  uint8_t buf[HASH_SIZE + sizeof(uint32_t) + 1];
+  memcpy(buf, &id, HASH_SIZE);
+  uint32_t v = SWAP32LE(nonce);
+  memcpy(buf + HASH_SIZE, &v, sizeof(uint32_t));
+  buf[HASH_SIZE + sizeof(uint32_t)] = config::HASH_KEY_MM_SLOT;
+
+  crypto::hash res;
+  tools::sha256sum(buf, sizeof(buf), res);
+  v = *((const uint32_t*)&res);
+  return SWAP32LE(v) % n_aux_chains;
+}
+//---------------------------------------------------------------
+uint32_t get_path_from_aux_slot(uint32_t slot, uint32_t n_aux_chains)
+{
+  CHECK_AND_ASSERT_THROW_MES(n_aux_chains > 0, "n_aux_chains is 0");
+  CHECK_AND_ASSERT_THROW_MES(slot < n_aux_chains, "slot >= n_aux_chains");
+
+  uint32_t path = 0;
+  CHECK_AND_ASSERT_THROW_MES(tree_path(n_aux_chains, slot, &path), "Failed to get path from aux slot");
+  return path;
+}
+//---------------------------------------------------------------
+uint32_t encode_mm_depth(uint32_t n_aux_chains, uint32_t nonce)
+{
+  CHECK_AND_ASSERT_THROW_MES(n_aux_chains > 0, "n_aux_chains is 0");
+
+  // how many bits to we need to representing n_aux_chains - 1
+  uint32_t n_bits = 1;
+  while ((1u << n_bits) < n_aux_chains && n_bits < 16)
+    ++n_bits;
+  CHECK_AND_ASSERT_THROW_MES(n_bits <= 16, "Way too many bits required");
+
+  const uint32_t depth = (n_bits - 1) | ((n_aux_chains - 1) << 3) | (nonce << (3 + n_bits));
+  return depth;
+}
+//---------------------------------------------------------------
+bool decode_mm_depth(uint32_t depth, uint32_t &n_aux_chains, uint32_t &nonce)
+{
+  const uint32_t n_bits = 1 + (depth & 7);
+  n_aux_chains = 1 + (depth >> 3 & ((1 << n_bits) - 1));
+  nonce = depth >> (3 + n_bits);
+  return true;
+}
+//---------------------------------------------------------------
+}
diff --git a/src/cryptonote_basic/merge_mining.h b/src/cryptonote_basic/merge_mining.h
new file mode 100644
index 000000000..378438f7c
--- /dev/null
+++ b/src/cryptonote_basic/merge_mining.h
@@ -0,0 +1,40 @@
+// Copyright (c) 2020, 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.
+
+#pragma once
+
+#include <stdint.h>
+#include "crypto/crypto.h"
+
+namespace cryptonote
+{
+  uint32_t get_aux_slot(const crypto::hash &id, uint32_t nonce, uint32_t n_aux_chains);
+  uint32_t get_path_from_aux_slot(uint32_t slot, uint32_t n_aux_chains);
+  uint32_t encode_mm_depth(uint32_t n_aux_chains, uint32_t nonce);
+  bool decode_mm_depth(uint32_t depth, uint32_t &n_aux_chains, uint32_t &nonce);
+}
diff --git a/src/cryptonote_config.h b/src/cryptonote_config.h
index 2cb28b2b1..33b65e2c0 100644
--- a/src/cryptonote_config.h
+++ b/src/cryptonote_config.h
@@ -235,6 +235,7 @@ namespace config
   const unsigned char HASH_KEY_CLSAG_AGG_0[] = "CLSAG_agg_0";
   const unsigned char HASH_KEY_CLSAG_AGG_1[] = "CLSAG_agg_1";
   const char HASH_KEY_MESSAGE_SIGNING[] = "MoneroMessageSignature";
+  const unsigned char HASH_KEY_MM_SLOT = 'm';
 
   namespace testnet
   {
diff --git a/src/debug_utilities/cn_deserialize.cpp b/src/debug_utilities/cn_deserialize.cpp
index dd4701e4f..c039b93c5 100644
--- a/src/debug_utilities/cn_deserialize.cpp
+++ b/src/debug_utilities/cn_deserialize.cpp
@@ -133,6 +133,18 @@ int main(int argc, char* argv[])
   {
     std::cout << "Parsed block:" << std::endl;
     std::cout << cryptonote::obj_to_json_str(block) << std::endl;
+    bool parsed = cryptonote::parse_tx_extra(block.miner_tx.extra, fields);
+    if (!parsed)
+      std::cout << "Failed to parse tx_extra" << std::endl;
+
+    if (!fields.empty())
+    {
+      print_extra_fields(fields);
+    }
+    else
+    {
+      std::cout << "No fields were found in tx_extra" << std::endl;
+    }
   }
   else if (cryptonote::parse_and_validate_tx_from_blob(blob, tx) || cryptonote::parse_and_validate_tx_base_from_blob(blob, tx))
   {
diff --git a/src/rpc/core_rpc_server.cpp b/src/rpc/core_rpc_server.cpp
index db228dd94..2ee342748 100644
--- a/src/rpc/core_rpc_server.cpp
+++ b/src/rpc/core_rpc_server.cpp
@@ -44,6 +44,7 @@ using namespace epee;
 #include "cryptonote_basic/cryptonote_format_utils.h"
 #include "cryptonote_basic/account.h"
 #include "cryptonote_basic/cryptonote_basic_impl.h"
+#include "cryptonote_basic/merge_mining.h"
 #include "cryptonote_core/tx_sanity_check.h"
 #include "misc_language.h"
 #include "net/parse.h"
@@ -1828,6 +1829,125 @@ namespace cryptonote
     return true;
   }
   //------------------------------------------------------------------------------------------------------------------------------
+  bool core_rpc_server::on_add_aux_pow(const COMMAND_RPC_ADD_AUX_POW::request& req, COMMAND_RPC_ADD_AUX_POW::response& res, epee::json_rpc::error& error_resp, const connection_context *ctx)
+  {
+    RPC_TRACKER(add_aux_pow);
+    bool r;
+    if (use_bootstrap_daemon_if_necessary<COMMAND_RPC_ADD_AUX_POW>(invoke_http_mode::JON_RPC, "add_aux_pow", req, res, r))
+      return r;
+
+    if (req.aux_pow.empty())
+    {
+      error_resp.code = CORE_RPC_ERROR_CODE_WRONG_PARAM;
+      error_resp.message = "Empty aux pow hash vector";
+      return false;
+    }
+
+    crypto::hash merkle_root;
+    size_t merkle_tree_depth = 0;
+    std::vector<std::pair<crypto::hash, crypto::hash>> aux_pow;
+    std::vector<crypto::hash> aux_pow_raw;
+    aux_pow.reserve(req.aux_pow.size());
+    aux_pow_raw.reserve(req.aux_pow.size());
+    for (const auto &s: req.aux_pow)
+    {
+      aux_pow.push_back({});
+      if (!epee::string_tools::hex_to_pod(s.id, aux_pow.back().first))
+      {
+        error_resp.code = CORE_RPC_ERROR_CODE_WRONG_PARAM;
+        error_resp.message = "Invalid aux pow id";
+        return false;
+      }
+      if (!epee::string_tools::hex_to_pod(s.hash, aux_pow.back().second))
+      {
+        error_resp.code = CORE_RPC_ERROR_CODE_WRONG_PARAM;
+        error_resp.message = "Invalid aux pow hash";
+        return false;
+      }
+      aux_pow_raw.push_back(aux_pow.back().second);
+    }
+
+    size_t path_domain = 1;
+    while ((1u << path_domain) < aux_pow.size())
+      ++path_domain;
+    uint32_t nonce;
+    const uint32_t max_nonce = 65535;
+    bool collision = true;
+    for (nonce = 0; nonce <= max_nonce; ++nonce)
+    {
+      std::vector<bool> slots(aux_pow.size(), false);
+      collision = false;
+      for (size_t idx = 0; idx < aux_pow.size(); ++idx)
+      {
+        const uint32_t slot = cryptonote::get_aux_slot(aux_pow[idx].first, nonce, aux_pow.size());
+        if (slot >= aux_pow.size())
+        {
+          error_resp.code = CORE_RPC_ERROR_CODE_INTERNAL_ERROR;
+          error_resp.message = "Computed slot is out of range";
+          return false;
+        }
+        if (slots[slot])
+        {
+          collision = true;
+          break;
+        }
+        slots[slot] = true;
+      }
+      if (!collision)
+        break;
+    }
+    if (collision)
+    {
+      error_resp.code = CORE_RPC_ERROR_CODE_INTERNAL_ERROR;
+      error_resp.message = "Failed to find a suitable nonce";
+      return false;
+    }
+
+    crypto::tree_hash((const char(*)[crypto::HASH_SIZE])aux_pow_raw.data(), aux_pow_raw.size(), merkle_root.data);
+    res.merkle_root = epee::string_tools::pod_to_hex(merkle_root);
+    res.merkle_tree_depth = cryptonote::encode_mm_depth(aux_pow.size(), nonce);
+
+    blobdata blocktemplate_blob;
+    if (!epee::string_tools::parse_hexstr_to_binbuff(req.blocktemplate_blob, blocktemplate_blob))
+    {
+      error_resp.code = CORE_RPC_ERROR_CODE_WRONG_PARAM;
+      error_resp.message = "Invalid blocktemplate_blob";
+      return false;
+    }
+
+    block b;
+    if (!parse_and_validate_block_from_blob(blocktemplate_blob, b))
+    {
+      error_resp.code = CORE_RPC_ERROR_CODE_WRONG_BLOCKBLOB;
+      error_resp.message = "Wrong blocktemplate_blob";
+      return false;
+    }
+
+    if (!remove_field_from_tx_extra(b.miner_tx.extra, typeid(cryptonote::tx_extra_merge_mining_tag)))
+    {
+      error_resp.code = CORE_RPC_ERROR_CODE_INTERNAL_ERROR;
+      error_resp.message = "Error removing existing merkle root";
+      return false;
+    }
+    if (!add_mm_merkle_root_to_tx_extra(b.miner_tx.extra, merkle_root, merkle_tree_depth))
+    {
+      error_resp.code = CORE_RPC_ERROR_CODE_INTERNAL_ERROR;
+      error_resp.message = "Error adding merkle root";
+      return false;
+    }
+    b.invalidate_hashes();
+    b.miner_tx.invalidate_hashes();
+
+    const blobdata block_blob = t_serializable_object_to_blob(b);
+    const blobdata hashing_blob = get_block_hashing_blob(b);
+
+    res.blocktemplate_blob = string_tools::buff_to_hex_nodelimer(block_blob);
+    res.blockhashing_blob = string_tools::buff_to_hex_nodelimer(hashing_blob);
+    res.aux_pow = req.aux_pow;
+    res.status = CORE_RPC_STATUS_OK;
+    return true;
+  }
+  //------------------------------------------------------------------------------------------------------------------------------
   bool core_rpc_server::on_submitblock(const COMMAND_RPC_SUBMITBLOCK::request& req, COMMAND_RPC_SUBMITBLOCK::response& res, epee::json_rpc::error& error_resp, const connection_context *ctx)
   {
     RPC_TRACKER(submitblock);
diff --git a/src/rpc/core_rpc_server.h b/src/rpc/core_rpc_server.h
index dcf6b4e4b..6736a6b7f 100644
--- a/src/rpc/core_rpc_server.h
+++ b/src/rpc/core_rpc_server.h
@@ -146,6 +146,7 @@ namespace cryptonote
         MAP_JON_RPC_WE("on_getblockhash",        on_getblockhash,               COMMAND_RPC_GETBLOCKHASH)
         MAP_JON_RPC_WE("get_block_template",     on_getblocktemplate,           COMMAND_RPC_GETBLOCKTEMPLATE)
         MAP_JON_RPC_WE("getblocktemplate",       on_getblocktemplate,           COMMAND_RPC_GETBLOCKTEMPLATE)
+        MAP_JON_RPC_WE("add_aux_pow",            on_add_aux_pow,                COMMAND_RPC_ADD_AUX_POW)
         MAP_JON_RPC_WE("submit_block",           on_submitblock,                COMMAND_RPC_SUBMITBLOCK)
         MAP_JON_RPC_WE("submitblock",            on_submitblock,                COMMAND_RPC_SUBMITBLOCK)
         MAP_JON_RPC_WE_IF("generateblocks",         on_generateblocks,             COMMAND_RPC_GENERATEBLOCKS, !m_restricted)
@@ -226,6 +227,7 @@ namespace cryptonote
     bool on_getblockcount(const COMMAND_RPC_GETBLOCKCOUNT::request& req, COMMAND_RPC_GETBLOCKCOUNT::response& res, const connection_context *ctx = NULL);
     bool on_getblockhash(const COMMAND_RPC_GETBLOCKHASH::request& req, COMMAND_RPC_GETBLOCKHASH::response& res, epee::json_rpc::error& error_resp, const connection_context *ctx = NULL);
     bool on_getblocktemplate(const COMMAND_RPC_GETBLOCKTEMPLATE::request& req, COMMAND_RPC_GETBLOCKTEMPLATE::response& res, epee::json_rpc::error& error_resp, const connection_context *ctx = NULL);
+    bool on_add_aux_pow(const COMMAND_RPC_ADD_AUX_POW::request& req, COMMAND_RPC_ADD_AUX_POW::response& res, epee::json_rpc::error& error_resp, const connection_context *ctx = NULL);
     bool on_submitblock(const COMMAND_RPC_SUBMITBLOCK::request& req, COMMAND_RPC_SUBMITBLOCK::response& res, epee::json_rpc::error& error_resp, const connection_context *ctx = NULL);
     bool on_generateblocks(const COMMAND_RPC_GENERATEBLOCKS::request& req, COMMAND_RPC_GENERATEBLOCKS::response& res, epee::json_rpc::error& error_resp, const connection_context *ctx = NULL);
     bool on_get_last_block_header(const COMMAND_RPC_GET_LAST_BLOCK_HEADER::request& req, COMMAND_RPC_GET_LAST_BLOCK_HEADER::response& res, epee::json_rpc::error& error_resp, const connection_context *ctx = NULL);
diff --git a/src/rpc/core_rpc_server_commands_defs.h b/src/rpc/core_rpc_server_commands_defs.h
index bbcb27f1c..e7bcb5570 100644
--- a/src/rpc/core_rpc_server_commands_defs.h
+++ b/src/rpc/core_rpc_server_commands_defs.h
@@ -88,7 +88,7 @@ namespace cryptonote
 // advance which version they will stop working with
 // Don't go over 32767 for any of these
 #define CORE_RPC_VERSION_MAJOR 3
-#define CORE_RPC_VERSION_MINOR 5
+#define CORE_RPC_VERSION_MINOR 6
 #define MAKE_CORE_RPC_VERSION(major,minor) (((major)<<16)|(minor))
 #define CORE_RPC_VERSION MAKE_CORE_RPC_VERSION(CORE_RPC_VERSION_MAJOR, CORE_RPC_VERSION_MINOR)
 
@@ -938,6 +938,52 @@ namespace cryptonote
     typedef epee::misc_utils::struct_init<response_t> response;
   };
 
+  struct COMMAND_RPC_ADD_AUX_POW
+  {
+    struct aux_pow_t
+    {
+      std::string id;
+      std::string hash;
+
+      BEGIN_KV_SERIALIZE_MAP()
+        KV_SERIALIZE(id)
+        KV_SERIALIZE(hash)
+      END_KV_SERIALIZE_MAP()
+    };
+
+    struct request_t: public rpc_request_base
+    {
+      blobdata blocktemplate_blob;
+      std::vector<aux_pow_t> aux_pow;
+
+      BEGIN_KV_SERIALIZE_MAP()
+        KV_SERIALIZE_PARENT(rpc_request_base)
+        KV_SERIALIZE(blocktemplate_blob)
+        KV_SERIALIZE(aux_pow)
+      END_KV_SERIALIZE_MAP()
+    };
+    typedef epee::misc_utils::struct_init<request_t> request;
+
+    struct response_t: public rpc_response_base
+    {
+      blobdata blocktemplate_blob;
+      blobdata blockhashing_blob;
+      std::string merkle_root;
+      uint32_t merkle_tree_depth;
+      std::vector<aux_pow_t> aux_pow;
+
+      BEGIN_KV_SERIALIZE_MAP()
+        KV_SERIALIZE_PARENT(rpc_response_base)
+        KV_SERIALIZE(blocktemplate_blob)
+        KV_SERIALIZE(blockhashing_blob)
+        KV_SERIALIZE(merkle_root)
+        KV_SERIALIZE(merkle_tree_depth)
+        KV_SERIALIZE(aux_pow)
+      END_KV_SERIALIZE_MAP()
+    };
+    typedef epee::misc_utils::struct_init<response_t> response;
+  };
+
   struct COMMAND_RPC_SUBMITBLOCK
   {
     typedef std::vector<std::string> request;