Change to Tx diffusion (Dandelion++ fluff) instead of flooding

4 files changed, 26 insertions, 10 deletions

diff --git a/src/p2p/net_node.cpp b/src/p2p/net_node.cpp
index 58c1717e0..58c5706de 100644
--- a/src/p2p/net_node.cpp
+++ b/src/p2p/net_node.cpp
@@ -161,6 +161,10 @@ namespace nodetool
     const command_line::arg_descriptor<int64_t> arg_limit_rate_down = {"limit-rate-down", "set limit-rate-down [kB/s]", P2P_DEFAULT_LIMIT_RATE_DOWN};
     const command_line::arg_descriptor<int64_t> arg_limit_rate = {"limit-rate", "set limit-rate [kB/s]", -1};
 
+    const command_line::arg_descriptor<bool> arg_pad_transactions = {
+      "pad-transactions", "Pad relayed transactions to help defend against traffic volume analysis", false
+    };
+
     boost::optional<std::vector<proxy>> get_proxies(boost::program_options::variables_map const& vm)
     {
         namespace ip = boost::asio::ip;
diff --git a/src/p2p/net_node.h b/src/p2p/net_node.h
index ee70c2806..0e9c1c942 100644
--- a/src/p2p/net_node.h
+++ b/src/p2p/net_node.h
@@ -38,6 +38,7 @@
 #include <boost/program_options/options_description.hpp>
 #include <boost/program_options/variables_map.hpp>
 #include <boost/uuid/uuid.hpp>
+#include <chrono>
 #include <functional>
 #include <utility>
 #include <vector>
@@ -109,8 +110,16 @@ namespace nodetool
   template<class base_type>
   struct p2p_connection_context_t: base_type //t_payload_net_handler::connection_context //public net_utils::connection_context_base
   {
-    p2p_connection_context_t(): peer_id(0), support_flags(0), m_in_timedsync(false) {}
+    p2p_connection_context_t()
+      : fluff_txs(),
+        flush_time(std::chrono::steady_clock::time_point::max()),
+        peer_id(0),
+        support_flags(0),
+        m_in_timedsync(false)
+    {}
 
+    std::vector<cryptonote::blobdata> fluff_txs;
+    std::chrono::steady_clock::time_point flush_time;
     peerid_type peer_id;
     uint32_t support_flags;
     bool m_in_timedsync;
@@ -337,7 +346,7 @@ namespace nodetool
     virtual void callback(p2p_connection_context& context);
     //----------------- i_p2p_endpoint -------------------------------------------------------------
     virtual bool relay_notify_to_list(int command, const epee::span<const uint8_t> data_buff, std::vector<std::pair<epee::net_utils::zone, boost::uuids::uuid>> connections);
-    virtual epee::net_utils::zone send_txs(std::vector<cryptonote::blobdata> txs, const epee::net_utils::zone origin, const boost::uuids::uuid& source, cryptonote::i_core_events& core, bool pad_txs);
+    virtual epee::net_utils::zone send_txs(std::vector<cryptonote::blobdata> txs, const epee::net_utils::zone origin, const boost::uuids::uuid& source, cryptonote::i_core_events& core);
     virtual bool invoke_command_to_peer(int command, const epee::span<const uint8_t> req_buff, std::string& resp_buff, const epee::net_utils::connection_context_base& context);
     virtual bool invoke_notify_to_peer(int command, const epee::span<const uint8_t> req_buff, const epee::net_utils::connection_context_base& context);
     virtual bool drop_connection(const epee::net_utils::connection_context_base& context);
@@ -540,6 +549,7 @@ namespace nodetool
     extern const command_line::arg_descriptor<int64_t> arg_limit_rate_up;
     extern const command_line::arg_descriptor<int64_t> arg_limit_rate_down;
     extern const command_line::arg_descriptor<int64_t> arg_limit_rate;
+    extern const command_line::arg_descriptor<bool> arg_pad_transactions;
 }
 
 POP_WARNINGS
diff --git a/src/p2p/net_node.inl b/src/p2p/net_node.inl
index 45bb10593..5dab251b5 100644
--- a/src/p2p/net_node.inl
+++ b/src/p2p/net_node.inl
@@ -116,6 +116,7 @@ namespace nodetool
     command_line::add_arg(desc, arg_limit_rate_up);
     command_line::add_arg(desc, arg_limit_rate_down);
     command_line::add_arg(desc, arg_limit_rate);
+    command_line::add_arg(desc, arg_pad_transactions);
   }
   //-----------------------------------------------------------------------------------
   template<class t_payload_net_handler>
@@ -340,6 +341,7 @@ namespace nodetool
   {
     bool testnet = command_line::get_arg(vm, cryptonote::arg_testnet_on);
     bool stagenet = command_line::get_arg(vm, cryptonote::arg_stagenet_on);
+    const bool pad_txs = command_line::get_arg(vm, arg_pad_transactions);
     m_nettype = testnet ? cryptonote::TESTNET : stagenet ? cryptonote::STAGENET : cryptonote::MAINNET;
 
     network_zone& public_zone = m_network_zones[epee::net_utils::zone::public_];
@@ -384,7 +386,7 @@ namespace nodetool
     m_use_ipv6 = command_line::get_arg(vm, arg_p2p_use_ipv6);
     m_require_ipv4 = !command_line::get_arg(vm, arg_p2p_ignore_ipv4);
     public_zone.m_notifier = cryptonote::levin::notify{
-      public_zone.m_net_server.get_io_service(), public_zone.m_net_server.get_config_shared(), nullptr, true
+      public_zone.m_net_server.get_io_service(), public_zone.m_net_server.get_config_shared(), nullptr, true, pad_txs
     };
 
     if (command_line::has_arg(vm, arg_p2p_add_peer))
@@ -495,7 +497,7 @@ namespace nodetool
       }
 
       zone.m_notifier = cryptonote::levin::notify{
-        zone.m_net_server.get_io_service(), zone.m_net_server.get_config_shared(), std::move(this_noise), false
+        zone.m_net_server.get_io_service(), zone.m_net_server.get_config_shared(), std::move(this_noise), false, pad_txs
       };
     }
 
@@ -2053,18 +2055,18 @@ namespace nodetool
   }
   //-----------------------------------------------------------------------------------
   template<class t_payload_net_handler>
-  epee::net_utils::zone node_server<t_payload_net_handler>::send_txs(std::vector<cryptonote::blobdata> txs, const epee::net_utils::zone origin, const boost::uuids::uuid& source, cryptonote::i_core_events& core, const bool pad_txs)
+  epee::net_utils::zone node_server<t_payload_net_handler>::send_txs(std::vector<cryptonote::blobdata> txs, const epee::net_utils::zone origin, const boost::uuids::uuid& source, cryptonote::i_core_events& core)
   {
     namespace enet = epee::net_utils;
 
-    const auto send = [&txs, &source, &core, pad_txs] (std::pair<const enet::zone, network_zone>& network)
+    const auto send = [&txs, &source, &core] (std::pair<const enet::zone, network_zone>& network)
     {
       const bool is_public = (network.first == enet::zone::public_);
       const cryptonote::relay_method tx_relay = is_public ?
-        cryptonote::relay_method::flood : cryptonote::relay_method::local;
+        cryptonote::relay_method::fluff : cryptonote::relay_method::local;
 
       core.on_transactions_relayed(epee::to_span(txs), tx_relay);
-      if (network.second.m_notifier.send_txs(std::move(txs), source, (pad_txs || !is_public)))
+      if (network.second.m_notifier.send_txs(std::move(txs), source))
         return network.first;
       return enet::zone::invalid;
     };
diff --git a/src/p2p/net_node_common.h b/src/p2p/net_node_common.h
index aa1b83b83..ed88aa28c 100644
--- a/src/p2p/net_node_common.h
+++ b/src/p2p/net_node_common.h
@@ -50,7 +50,7 @@ namespace nodetool
   struct i_p2p_endpoint
   {
     virtual bool relay_notify_to_list(int command, const epee::span<const uint8_t> data_buff, std::vector<std::pair<epee::net_utils::zone, boost::uuids::uuid>> connections)=0;
-    virtual epee::net_utils::zone send_txs(std::vector<cryptonote::blobdata> txs, const epee::net_utils::zone origin, const boost::uuids::uuid& source, cryptonote::i_core_events& core, bool pad_txs)=0;
+    virtual epee::net_utils::zone send_txs(std::vector<cryptonote::blobdata> txs, const epee::net_utils::zone origin, const boost::uuids::uuid& source, cryptonote::i_core_events& core)=0;
     virtual bool invoke_command_to_peer(int command, const epee::span<const uint8_t> req_buff, std::string& resp_buff, const epee::net_utils::connection_context_base& context)=0;
     virtual bool invoke_notify_to_peer(int command, const epee::span<const uint8_t> req_buff, const epee::net_utils::connection_context_base& context)=0;
     virtual bool drop_connection(const epee::net_utils::connection_context_base& context)=0;
@@ -75,7 +75,7 @@ namespace nodetool
     {
       return false;
     }
-    virtual epee::net_utils::zone send_txs(std::vector<cryptonote::blobdata> txs, const epee::net_utils::zone origin, const boost::uuids::uuid& source, cryptonote::i_core_events& core, const bool pad_txs)
+    virtual epee::net_utils::zone send_txs(std::vector<cryptonote::blobdata> txs, const epee::net_utils::zone origin, const boost::uuids::uuid& source, cryptonote::i_core_events& core)
     {
       return epee::net_utils::zone::invalid;
     }