MMS (Multisig Messaging System): Initial version

src/common/util.cpp

@@ -58,6 +58,7 @@
 #include "include_base_utils.h"
 #include "file_io_utils.h"
 #include "wipeable_string.h"
+#include "misc_os_dependent.h"
 using namespace epee;
 
 #include "crypto/crypto.h"
@@ -1025,4 +1026,15 @@ std::string get_nix_version_display_string()
 #endif
   }
 
+  std::string get_human_readable_timestamp(uint64_t ts)
+  {
+    char buffer[64];
+    if (ts < 1234567890)
+      return "<unknown>";
+    time_t tt = ts;
+    struct tm tm;
+    misc_utils::get_gmt_time(tt, tm);
+    strftime(buffer, sizeof(buffer), "%Y-%m-%d %H:%M:%S", &tm);
+    return std::string(buffer);
+  }
 }

src/common/util.h

@@ -242,4 +242,6 @@ namespace tools
 #endif
 
   void closefrom(int fd);
+
+  std::string get_human_readable_timestamp(uint64_t ts);
 }

src/simplewallet/simplewallet.h

@@ -154,7 +154,7 @@ namespace cryptonote
     bool show_incoming_transfers(const std::vector<std::string> &args);
     bool show_payments(const std::vector<std::string> &args);
     bool show_blockchain_height(const std::vector<std::string> &args);
-    bool transfer_main(int transfer_type, const std::vector<std::string> &args);
+    bool transfer_main(int transfer_type, const std::vector<std::string> &args, bool called_by_mms);
     bool transfer(const std::vector<std::string> &args);
     bool locked_transfer(const std::vector<std::string> &args);
     bool locked_sweep_all(const std::vector<std::string> &args);
@@ -214,15 +214,23 @@ namespace cryptonote
     bool payment_id(const std::vector<std::string> &args);
     bool print_fee_info(const std::vector<std::string> &args);
     bool prepare_multisig(const std::vector<std::string>& args);
+    bool prepare_multisig_main(const std::vector<std::string>& args, bool called_by_mms);
     bool make_multisig(const std::vector<std::string>& args);
+    bool make_multisig_main(const std::vector<std::string>& args, bool called_by_mms);
     bool finalize_multisig(const std::vector<std::string> &args);
     bool exchange_multisig_keys(const std::vector<std::string> &args);
+    bool exchange_multisig_keys_main(const std::vector<std::string> &args, bool called_by_mms);
     bool export_multisig(const std::vector<std::string>& args);
+    bool export_multisig_main(const std::vector<std::string>& args, bool called_by_mms);
     bool import_multisig(const std::vector<std::string>& args);
+    bool import_multisig_main(const std::vector<std::string>& args, bool called_by_mms);
     bool accept_loaded_tx(const tools::wallet2::multisig_tx_set &txs);
     bool sign_multisig(const std::vector<std::string>& args);
+    bool sign_multisig_main(const std::vector<std::string>& args, bool called_by_mms);
     bool submit_multisig(const std::vector<std::string>& args);
+    bool submit_multisig_main(const std::vector<std::string>& args, bool called_by_mms);
     bool export_raw_multisig(const std::vector<std::string>& args);
+    bool mms(const std::vector<std::string>& args);
     bool print_ring(const std::vector<std::string>& args);
     bool set_ring(const std::vector<std::string>& args);
     bool save_known_rings(const std::vector<std::string>& args);
@@ -386,5 +394,40 @@ namespace cryptonote
     bool m_auto_refresh_refreshing;
     std::atomic<bool> m_in_manual_refresh;
     uint32_t m_current_subaddress_account;
+    
+    // MMS
+    mms::message_store& get_message_store() const { return m_wallet->get_message_store(); };
+    mms::multisig_wallet_state get_multisig_wallet_state() const { return m_wallet->get_multisig_wallet_state(); };
+    bool mms_active() const { return get_message_store().get_active(); };
+    bool choose_mms_processing(const std::vector<mms::processing_data> &data_list, uint32_t &choice);
+    void list_mms_messages(const std::vector<mms::message> &messages);
+    void list_signers(const std::vector<mms::authorized_signer> &signers);
+    void add_signer_config_messages();
+    void show_message(const mms::message &m);
+    void ask_send_all_ready_messages();
+    void check_for_messages();
+    bool user_confirms(const std::string &question);
+    bool get_message_from_arg(const std::string &arg, mms::message &m);
+    bool get_number_from_arg(const std::string &arg, uint32_t &number, const uint32_t lower_bound, const uint32_t upper_bound); 
+
+    void mms_init(const std::vector<std::string> &args);
+    void mms_info(const std::vector<std::string> &args);
+    void mms_signer(const std::vector<std::string> &args);
+    void mms_list(const std::vector<std::string> &args);
+    void mms_next(const std::vector<std::string> &args);
+    void mms_sync(const std::vector<std::string> &args);
+    void mms_transfer(const std::vector<std::string> &args);
+    void mms_delete(const std::vector<std::string> &args);
+    void mms_send(const std::vector<std::string> &args);
+    void mms_receive(const std::vector<std::string> &args);
+    void mms_export(const std::vector<std::string> &args);
+    void mms_note(const std::vector<std::string> &args);
+    void mms_show(const std::vector<std::string> &args);
+    void mms_set(const std::vector<std::string> &args);
+    void mms_help(const std::vector<std::string> &args);
+    void mms_send_signer_config(const std::vector<std::string> &args);
+    void mms_start_auto_config(const std::vector<std::string> &args);
+    void mms_stop_auto_config(const std::vector<std::string> &args);
+    void mms_auto_config(const std::vector<std::string> &args);
   };
 }

src/wallet/CMakeLists.txt

@@ -34,7 +34,10 @@ set(wallet_sources
   wallet2.cpp
   wallet_args.cpp
   ringdb.cpp
-  node_rpc_proxy.cpp)
+  node_rpc_proxy.cpp
+  message_store.cpp
+  message_transporter.cpp
+)
 
 set(wallet_private_headers
   wallet2.h
@@ -44,7 +47,9 @@ set(wallet_private_headers
   wallet_rpc_server_commands_defs.h
   wallet_rpc_server_error_codes.h
   ringdb.h
-  node_rpc_proxy.h)
+  node_rpc_proxy.h
+  message_store.h
+  message_transporter.h)
 
 monero_private_headers(wallet
   ${wallet_private_headers})

src/wallet/message_store.h

@@ -0,0 +1,420 @@
+// Copyright (c) 2018, 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 <cstdlib>
+#include <string>
+#include <vector>
+#include "crypto/hash.h"
+#include <boost/serialization/vector.hpp>
+#include <boost/program_options/variables_map.hpp>
+#include <boost/program_options/options_description.hpp>
+#include <boost/optional/optional.hpp>
+#include "serialization/serialization.h"
+#include "cryptonote_basic/cryptonote_boost_serialization.h"
+#include "cryptonote_basic/account_boost_serialization.h"
+#include "cryptonote_basic/cryptonote_basic.h"
+#include "common/i18n.h"
+#include "common/command_line.h"
+#include "wipeable_string.h"
+#include "message_transporter.h"
+
+#undef MONERO_DEFAULT_LOG_CATEGORY
+#define MONERO_DEFAULT_LOG_CATEGORY "wallet.mms"
+#define AUTO_CONFIG_TOKEN_BYTES 4
+#define AUTO_CONFIG_TOKEN_PREFIX "mms"
+
+namespace mms
+{
+  enum class message_type
+  {
+    key_set,
+    additional_key_set,
+    multisig_sync_data,
+    partially_signed_tx,
+    fully_signed_tx,
+    note,
+    signer_config,
+    auto_config_data
+  };
+
+  enum class message_direction
+  {
+    in,
+    out
+  };
+
+  enum class message_state
+  {
+    ready_to_send,
+    sent,
+
+    waiting,
+    processed,
+
+    cancelled
+  };
+
+  enum class message_processing
+  {
+    prepare_multisig,
+    make_multisig,
+    exchange_multisig_keys,
+    create_sync_data,
+    process_sync_data,
+    sign_tx,
+    send_tx,
+    submit_tx,
+    process_signer_config,
+    process_auto_config_data
+  };
+
+  struct message
+  {
+    uint32_t id;
+    message_type type;
+    message_direction direction;
+    std::string content;
+    uint64_t created;
+    uint64_t modified;
+    uint64_t sent;
+    uint32_t signer_index;
+    crypto::hash hash;
+    message_state state;
+    uint32_t wallet_height;
+    uint32_t round;
+    uint32_t signature_count;
+    std::string transport_id;
+  };
+  // "wallet_height" (for lack of a short name that would describe what it is about)
+  // is the number of transfers present in the wallet at the time of message
+  // construction; used to coordinate generation of sync info (which depends
+  // on the content of the wallet at time of generation)
+
+  struct authorized_signer
+  {
+    std::string label;
+    std::string transport_address;
+    bool monero_address_known;
+    cryptonote::account_public_address monero_address;
+    bool me;
+    uint32_t index;
+    std::string auto_config_token;
+    crypto::public_key auto_config_public_key;
+    crypto::secret_key auto_config_secret_key;
+    std::string auto_config_transport_address;
+    bool auto_config_running;
+
+    authorized_signer()
+    {
+      monero_address_known = false;
+      memset(&monero_address, 0, sizeof(cryptonote::account_public_address));
+      index = 0;
+      auto_config_public_key = crypto::null_pkey;
+      auto_config_secret_key = crypto::null_skey;
+      auto_config_running = false;
+    };
+  };
+
+  struct processing_data
+  {
+    message_processing processing;
+    std::vector<uint32_t> message_ids;
+    uint32_t receiving_signer_index = 0;
+  };
+
+  struct file_transport_message
+  {
+    cryptonote::account_public_address sender_address;
+    crypto::chacha_iv iv;
+    crypto::public_key encryption_public_key;
+    message internal_message;
+  };
+  
+  struct auto_config_data
+  {
+    std::string label;
+    std::string transport_address;
+    cryptonote::account_public_address monero_address;
+  };
+
+  // Overal .mms file structure, with the "message_store" object serialized to and
+  // encrypted in "encrypted_data"
+  struct file_data
+  {
+    std::string magic_string;
+    uint32_t file_version;
+    crypto::chacha_iv iv;
+    std::string encrypted_data;
+  };
+
+    // The following struct provides info about the current state of a "wallet2" object
+  // at the time of a "message_store" method call that those methods need. See on the
+  // one hand a first parameter of this type for several of those methods, and on the
+  // other hand the method "wallet2::get_multisig_wallet_state" which clients like the
+  // CLI wallet can use to get that info.
+  //
+  // Note that in the case of a wallet that is already multisig "address" is NOT the
+  // multisig address, but the "original" wallet address at creation time. Likewise
+  // "view_secret_key" is the original view secret key then.
+  //
+  // This struct definition is here and not in "wallet2.h" to avoid circular imports.
+  struct multisig_wallet_state
+  {
+    cryptonote::account_public_address address;
+    cryptonote::network_type nettype;
+    crypto::secret_key view_secret_key;
+    bool multisig;
+    bool multisig_is_ready;
+    bool has_multisig_partial_key_images;
+    uint32_t multisig_rounds_passed;
+    size_t num_transfer_details;
+    std::string mms_file;
+  };
+
+  class message_store
+  {
+  public:
+    message_store();
+    // Initialize and start to use the MMS, set the first signer, this wallet itself
+    // Filename, if not null and not empty, is used to create the ".mms" file
+    // reset it if already used, with deletion of all signers and messages
+    void init(const multisig_wallet_state &state, const std::string &own_label,
+              const std::string &own_transport_address, uint32_t num_authorized_signers, uint32_t num_required_signers);
+    void set_active(bool active) { m_active = active; };
+    void set_auto_send(bool auto_send) { m_auto_send = auto_send; };
+    void set_options(const boost::program_options::variables_map& vm);
+    void set_options(const std::string &bitmessage_address, const epee::wipeable_string &bitmessage_login);
+    bool get_active() const { return m_active; };
+    bool get_auto_send() const { return m_auto_send; };
+    uint32_t get_num_required_signers() const { return m_num_required_signers; };
+    uint32_t get_num_authorized_signers() const { return m_num_authorized_signers; };
+
+    void set_signer(const multisig_wallet_state &state,
+                    uint32_t index,
+                    const boost::optional<std::string> &label,
+                    const boost::optional<std::string> &transport_address,
+                    const boost::optional<cryptonote::account_public_address> monero_address);
+
+    const authorized_signer &get_signer(uint32_t index) const;
+    bool get_signer_index_by_monero_address(const cryptonote::account_public_address &monero_address, uint32_t &index) const;
+    bool get_signer_index_by_label(const std::string label, uint32_t &index) const;
+    const std::vector<authorized_signer> &get_all_signers() const { return m_signers; };
+    bool signer_config_complete() const;
+    bool signer_labels_complete() const;
+    void get_signer_config(std::string &signer_config);
+    void unpack_signer_config(const multisig_wallet_state &state, const std::string &signer_config,
+                              std::vector<authorized_signer> &signers);
+    void process_signer_config(const multisig_wallet_state &state, const std::string &signer_config);
+
+    void start_auto_config(const multisig_wallet_state &state);
+    bool check_auto_config_token(const std::string &raw_token,
+                                 std::string &adjusted_token) const;
+    size_t add_auto_config_data_message(const multisig_wallet_state &state,
+                                        const std::string &auto_config_token);
+    void process_auto_config_data_message(uint32_t id);
+    void stop_auto_config();
+
+    // Process data just created by "me" i.e. the own local wallet, e.g. as the result of a "prepare_multisig" command
+    // Creates the resulting messages to the right signers
+    void process_wallet_created_data(const multisig_wallet_state &state, message_type type, const std::string &content);
+
+    // Go through all the messages, look at the "ready to process" ones, and check whether any single one
+    // or any group of them can be processed, because they are processable as single messages (like a tx
+    // that is fully signed and thus ready for submit to the net) or because they form a complete group
+    // (e.g. key sets from all authorized signers to make the wallet multisig). If there are multiple
+    // candidates, e.g. in 2/3 multisig sending to one OR the other signer to sign, there will be more
+    // than 1 element in 'data' for the user to choose. If nothing is ready "false" is returned.
+    // The method mostly ignores the order in which the messages were received because messages may be delayed
+    // (e.g. sync data from a signer arrives AFTER a transaction to submit) or because message time stamps
+    // may be wrong so it's not possible to order them reliably.
+    // Messages also may be ready by themselves but the wallet not yet ready for them (e.g. sync data already
+    // arriving when the wallet is not yet multisig because key sets were delayed or were lost altogether.)
+    // If nothing is ready 'wait_reason' may contain further info about the reason why.
+    bool get_processable_messages(const multisig_wallet_state &state,
+                                  bool force_sync,
+                                  std::vector<processing_data> &data_list,
+                                  std::string &wait_reason);
+    void set_messages_processed(const processing_data &data);
+
+    size_t add_message(const multisig_wallet_state &state,
+                       uint32_t signer_index, message_type type, message_direction direction,
+                       const std::string &content);
+    const std::vector<message> &get_all_messages() const { return m_messages; };
+    bool get_message_by_id(uint32_t id, message &m) const;
+    message get_message_by_id(uint32_t id) const;
+    void set_message_processed_or_sent(uint32_t id);
+    void delete_message(uint32_t id);
+    void delete_all_messages();
+    void get_sanitized_message_text(const message &m, std::string &sanitized_text) const;
+
+    void send_message(const multisig_wallet_state &state, uint32_t id);
+    bool check_for_messages(const multisig_wallet_state &state, std::vector<message> &messages);
+    void stop() { m_run.store(false, std::memory_order_relaxed); m_transporter.stop(); }
+
+    void write_to_file(const multisig_wallet_state &state, const std::string &filename);
+    void read_from_file(const multisig_wallet_state &state, const std::string &filename);
+
+    template <class t_archive>
+    inline void serialize(t_archive &a, const unsigned int ver)
+    {
+      a & m_active;
+      a & m_num_authorized_signers;
+      a & m_nettype;
+      a & m_num_required_signers;
+      a & m_signers;
+      a & m_messages;
+      a & m_next_message_id;
+      a & m_auto_send;
+    }
+
+    static const char* message_type_to_string(message_type type);
+    static const char* message_direction_to_string(message_direction direction);
+    static const char* message_state_to_string(message_state state);
+    std::string signer_to_string(const authorized_signer &signer, uint32_t max_width);
+    
+    static const char *tr(const char *str) { return i18n_translate(str, "tools::mms"); }
+    static void init_options(boost::program_options::options_description& desc_params);
+
+  private:
+    bool m_active;
+    uint32_t m_num_authorized_signers;
+    uint32_t m_num_required_signers;
+    bool m_auto_send;
+    cryptonote::network_type m_nettype;
+    std::vector<authorized_signer> m_signers;
+    std::vector<message> m_messages;
+    uint32_t m_next_message_id;
+    std::string m_filename;
+    message_transporter m_transporter;
+    std::atomic<bool> m_run;
+
+    bool get_message_index_by_id(uint32_t id, size_t &index) const;
+    size_t get_message_index_by_id(uint32_t id) const;
+    message& get_message_ref_by_id(uint32_t id);
+    bool any_message_of_type(message_type type, message_direction direction) const;
+    bool any_message_with_hash(const crypto::hash &hash) const;
+    size_t get_other_signers_id_count(const std::vector<uint32_t> &ids) const;
+    bool message_ids_complete(const std::vector<uint32_t> &ids) const;
+    void encrypt(crypto::public_key public_key, const std::string &plaintext,
+                 std::string &ciphertext, crypto::public_key &encryption_public_key, crypto::chacha_iv &iv);
+    void decrypt(const std::string &ciphertext, const crypto::public_key &encryption_public_key, const crypto::chacha_iv &iv,
+                 const crypto::secret_key &view_secret_key, std::string &plaintext);
+    std::string create_auto_config_token();
+    void setup_signer_for_auto_config(uint32_t index, const std::string token, bool receiving);
+    void delete_transport_message(uint32_t id);
+    std::string account_address_to_string(const cryptonote::account_public_address &account_address) const;
+    void save(const multisig_wallet_state &state);
+  };
+}
+
+BOOST_CLASS_VERSION(mms::file_data, 0)
+BOOST_CLASS_VERSION(mms::message_store, 0)
+BOOST_CLASS_VERSION(mms::message, 0)
+BOOST_CLASS_VERSION(mms::file_transport_message, 0)
+BOOST_CLASS_VERSION(mms::authorized_signer, 1)
+BOOST_CLASS_VERSION(mms::auto_config_data, 0)
+
+namespace boost
+{
+  namespace serialization
+  {
+    template <class Archive>
+    inline void serialize(Archive &a, mms::file_data &x, const boost::serialization::version_type ver)
+    {
+      a & x.magic_string;
+      a & x.file_version;
+      a & x.iv;
+      a & x.encrypted_data;
+    }
+
+    template <class Archive>
+    inline void serialize(Archive &a, mms::message &x, const boost::serialization::version_type ver)
+    {
+      a & x.id;
+      a & x.type;
+      a & x.direction;
+      a & x.content;
+      a & x.created;
+      a & x.modified;
+      a & x.sent;
+      a & x.signer_index;
+      a & x.hash;
+      a & x.state;
+      a & x.wallet_height;
+      a & x.round;
+      a & x.signature_count;
+      a & x.transport_id;
+    }
+
+    template <class Archive>
+    inline void serialize(Archive &a, mms::authorized_signer &x, const boost::serialization::version_type ver)
+    {
+      a & x.label;
+      a & x.transport_address;
+      a & x.monero_address_known;
+      a & x.monero_address;
+      a & x.me;
+      a & x.index;
+      if (ver < 1)
+      {
+        return;
+      }
+      a & x.auto_config_token;
+      a & x.auto_config_public_key;
+      a & x.auto_config_secret_key;
+      a & x.auto_config_transport_address;
+      a & x.auto_config_running;  
+    }
+
+    template <class Archive>
+    inline void serialize(Archive &a, mms::auto_config_data &x, const boost::serialization::version_type ver)
+    {
+      a & x.label;
+      a & x.transport_address;
+      a & x.monero_address;
+    }
+
+    template <class Archive>
+    inline void serialize(Archive &a, mms::file_transport_message &x, const boost::serialization::version_type ver)
+    {
+      a & x.sender_address;
+      a & x.iv;
+      a & x.encryption_public_key;
+      a & x.internal_message;
+    }
+
+    template <class Archive>
+    inline void serialize(Archive &a, crypto::chacha_iv &x, const boost::serialization::version_type ver)
+    {
+      a & x.data;
+    }
+
+  }
+}

src/wallet/message_transporter.cpp

@@ -0,0 +1,317 @@
+// Copyright (c) 2018, 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 "message_transporter.h"
+#include "string_coding.h"
+#include <boost/format.hpp>
+#include "wallet_errors.h"
+#include "net/http_client.h"
+#include "net/net_parse_helpers.h"
+#include <algorithm>
+
+#undef MONERO_DEFAULT_LOG_CATEGORY
+#define MONERO_DEFAULT_LOG_CATEGORY "wallet.mms"
+#define PYBITMESSAGE_DEFAULT_API_PORT 8442
+
+namespace mms
+{
+
+namespace bitmessage_rpc
+{
+
+  struct message_info
+  {
+    uint32_t encodingType;
+    std::string toAddress;
+    uint32_t read;
+    std::string msgid;
+    std::string message;
+    std::string fromAddress;
+    std::string receivedTime;
+    std::string subject;
+
+    BEGIN_KV_SERIALIZE_MAP()
+      KV_SERIALIZE(encodingType)
+      KV_SERIALIZE(toAddress)
+      KV_SERIALIZE(read)
+      KV_SERIALIZE(msgid)
+      KV_SERIALIZE(message);
+      KV_SERIALIZE(fromAddress)
+      KV_SERIALIZE(receivedTime)
+      KV_SERIALIZE(subject)
+    END_KV_SERIALIZE_MAP()
+  };
+
+  struct inbox_messages_response
+  {
+    std::vector<message_info> inboxMessages;
+
+    BEGIN_KV_SERIALIZE_MAP()
+      KV_SERIALIZE(inboxMessages)
+    END_KV_SERIALIZE_MAP()
+  };
+
+}
+
+message_transporter::message_transporter()
+{
+  m_run = true;
+}
+
+void message_transporter::set_options(const std::string &bitmessage_address, const epee::wipeable_string &bitmessage_login)
+{
+  m_bitmessage_url = bitmessage_address;
+  epee::net_utils::http::url_content address_parts{};
+  epee::net_utils::parse_url(m_bitmessage_url, address_parts);
+  if (address_parts.port == 0)
+  {
+    address_parts.port = PYBITMESSAGE_DEFAULT_API_PORT;
+  }
+  m_bitmessage_login = bitmessage_login;
+
+  m_http_client.set_server(address_parts.host, std::to_string(address_parts.port), boost::none);
+}
+
+bool message_transporter::receive_messages(const std::vector<std::string> &destination_transport_addresses,
+                                           std::vector<transport_message> &messages)
+{
+  // The message body of the Bitmessage message is basically the transport message, as JSON (and nothing more).
+  // Weeding out other, non-MMS messages is done in a simple way: If it deserializes without error, it's an MMS message
+  // That JSON is Base64-encoded by the MMS because the Monero epee JSON serializer does not escape anything and happily
+  // includes even 0 (NUL) in strings, which might confuse Bitmessage or at least display confusingly in the client.
+  // There is yet another Base64-encoding of course as part of the Bitmessage API for the message body parameter
+  // The Bitmessage API call "getAllInboxMessages" gives back a JSON array with all the messages (despite using
+  // XML-RPC for the calls, and not JSON-RPC ...)
+  m_run.store(true, std::memory_order_relaxed);
+  std::string request;
+  start_xml_rpc_cmd(request, "getAllInboxMessages");
+  end_xml_rpc_cmd(request);
+  std::string answer;
+  post_request(request, answer);
+
+  std::string json = get_str_between_tags(answer, "<string>", "</string>");
+  bitmessage_rpc::inbox_messages_response bitmessage_res;
+  epee::serialization::load_t_from_json(bitmessage_res, json);
+  size_t size = bitmessage_res.inboxMessages.size();
+  messages.clear();
+
+  for (size_t i = 0; i < size; ++i)
+  {
+    if (!m_run.load(std::memory_order_relaxed))
+    {
+      // Stop was called, don't waste time processing any more messages
+      return false;
+    }
+    const bitmessage_rpc::message_info &message_info = bitmessage_res.inboxMessages[i];
+    if (std::find(destination_transport_addresses.begin(), destination_transport_addresses.end(), message_info.toAddress) != destination_transport_addresses.end())
+    {
+      transport_message message;
+      bool is_mms_message = false;
+      try
+      {
+        // First Base64-decoding: The message body is Base64 in the Bitmessage API
+        std::string message_body = epee::string_encoding::base64_decode(message_info.message);
+        // Second Base64-decoding: The MMS uses Base64 to hide non-textual data in its JSON from Bitmessage
+        json = epee::string_encoding::base64_decode(message_body);
+        epee::serialization::load_t_from_json(message, json);
+        is_mms_message = true;
+      }
+      catch(const std::exception& e)
+      {
+      }
+      if (is_mms_message)
+      {
+        message.transport_id = message_info.msgid;
+        messages.push_back(message);
+      }
+    }
+  }
+
+  return true;
+}
+
+bool message_transporter::send_message(const transport_message &message)
+{
+  // <toAddress> <fromAddress> <subject> <message> [encodingType [TTL]]
+  std::string request;
+  start_xml_rpc_cmd(request, "sendMessage");
+  add_xml_rpc_string_param(request, message.destination_transport_address);
+  add_xml_rpc_string_param(request, message.source_transport_address);
+  add_xml_rpc_base64_param(request, message.subject);
+  std::string json = epee::serialization::store_t_to_json(message);
+  std::string message_body = epee::string_encoding::base64_encode(json);  // See comment in "receive_message" about reason for (double-)Base64 encoding
+  add_xml_rpc_base64_param(request, message_body);
+  add_xml_rpc_integer_param(request, 2);
+  end_xml_rpc_cmd(request);
+  std::string answer;
+  post_request(request, answer);
+  return true;
+}
+
+bool message_transporter::delete_message(const std::string &transport_id)
+{
+  std::string request;
+  start_xml_rpc_cmd(request, "trashMessage");
+  add_xml_rpc_string_param(request, transport_id);
+  end_xml_rpc_cmd(request);
+  std::string answer;
+  post_request(request, answer);
+  return true;
+}
+
+// Deterministically derive a transport / Bitmessage address from 'seed' (the 10-hex-digits
+// auto-config token will be used), but do not set it up for receiving in PyBitmessage as
+// well, because it's possible the address will only ever be used to SEND auto-config data
+std::string message_transporter::derive_transport_address(const std::string &seed)
+{
+  std::string request;
+  start_xml_rpc_cmd(request, "getDeterministicAddress");
+  add_xml_rpc_base64_param(request, seed);
+  add_xml_rpc_integer_param(request, 4);  // addressVersionNumber
+  add_xml_rpc_integer_param(request, 1);  // streamNumber
+  end_xml_rpc_cmd(request);
+  std::string answer;
+  post_request(request, answer);
+  std::string address = get_str_between_tags(answer, "<string>", "</string>");
+  return address;
+}
+
+// Derive a transport address and configure it for receiving in PyBitmessage, typically
+// for receiving auto-config messages by the wallet of the auto-config organizer
+std::string message_transporter::derive_and_receive_transport_address(const std::string &seed)
+{
+  // We need to call both "get_deterministic_address" AND "createDeterministicAddresses"
+  // because we won't get back the address from the latter call if it exists already
+  std::string address = derive_transport_address(seed);
+
+  std::string request;
+  start_xml_rpc_cmd(request, "createDeterministicAddresses");
+  add_xml_rpc_base64_param(request, seed);
+  add_xml_rpc_integer_param(request, 1);  // numberOfAddresses
+  add_xml_rpc_integer_param(request, 4);  // addressVersionNumber
+  end_xml_rpc_cmd(request);
+  std::string answer;
+  post_request(request, answer);
+
+  return address;
+}
+
+bool message_transporter::delete_transport_address(const std::string &transport_address)
+{
+  std::string request;
+  start_xml_rpc_cmd(request, "deleteAddress");
+  add_xml_rpc_string_param(request, transport_address);
+  end_xml_rpc_cmd(request);
+  std::string answer;
+  return post_request(request, answer);
+}
+
+bool message_transporter::post_request(const std::string &request, std::string &answer)
+{
+  // Somehow things do not work out if one tries to connect "m_http_client" to Bitmessage
+  // and keep it connected over the course of several calls. But with a new connection per
+  // call and disconnecting after the call there is no problem (despite perhaps a small
+  // slowdown)
+  epee::net_utils::http::fields_list additional_params;
+
+  // Basic access authentication according to RFC 7617 (which the epee HTTP classes do not seem to support?)
+  // "m_bitmessage_login" just contains what is needed here, "user:password"
+  std::string auth_string = epee::string_encoding::base64_encode((const unsigned char*)m_bitmessage_login.data(), m_bitmessage_login.size());
+  auth_string.insert(0, "Basic ");
+  additional_params.push_back(std::make_pair("Authorization", auth_string));
+
+  additional_params.push_back(std::make_pair("Content-Type", "application/xml; charset=utf-8"));
+  const epee::net_utils::http::http_response_info* response = NULL;
+  std::chrono::milliseconds timeout = std::chrono::seconds(15);
+  bool r = m_http_client.invoke("/", "POST", request, timeout, std::addressof(response), std::move(additional_params));
+  if (r)
+  {
+    answer = response->m_body;
+  }
+  else
+  {
+    LOG_ERROR("POST request to Bitmessage failed: " << request.substr(0, 300));
+    THROW_WALLET_EXCEPTION(tools::error::no_connection_to_bitmessage, m_bitmessage_url);
+  }
+  m_http_client.disconnect();  // see comment above
+  std::string string_value = get_str_between_tags(answer, "<string>", "</string>");
+  if ((string_value.find("API Error") == 0) || (string_value.find("RPC ") == 0))
+  {
+    THROW_WALLET_EXCEPTION(tools::error::bitmessage_api_error, string_value);
+  }
+
+  return r;
+}
+
+// Pick some string between two delimiters
+// When parsing the XML returned by PyBitmessage, don't bother to fully parse it but as a little hack rely on the
+// fact that e.g. a single string returned will be, however deeply nested in "<params><param><value>...", delivered
+// between the very first "<string>" and "</string>" tags to be found in the XML
+std::string message_transporter::get_str_between_tags(const std::string &s, const std::string &start_delim, const std::string &stop_delim)
+{
+  size_t first_delim_pos = s.find(start_delim);
+  if (first_delim_pos != std::string::npos)
+  {
+    size_t end_pos_of_first_delim = first_delim_pos + start_delim.length();
+    size_t last_delim_pos = s.find(stop_delim);
+    if (last_delim_pos != std::string::npos)
+    {
+      return s.substr(end_pos_of_first_delim, last_delim_pos - end_pos_of_first_delim);
+    }
+  }
+  return std::string();
+}
+
+void message_transporter::start_xml_rpc_cmd(std::string &xml, const std::string &method_name)
+{
+  xml = (boost::format("<?xml version=\"1.0\"?><methodCall><methodName>%s</methodName><params>") % method_name).str();
+}
+
+void message_transporter::add_xml_rpc_string_param(std::string &xml, const std::string &param)
+{
+  xml += (boost::format("<param><value><string>%s</string></value></param>") % param).str();
+}
+
+void message_transporter::add_xml_rpc_base64_param(std::string &xml, const std::string &param)
+{
+  // Bitmessage expects some arguments Base64-encoded, but it wants them as parameters of type "string", not "base64" that is also part of XML-RPC
+  std::string encoded_param = epee::string_encoding::base64_encode(param);
+  xml += (boost::format("<param><value><string>%s</string></value></param>") % encoded_param).str();
+}
+
+void message_transporter::add_xml_rpc_integer_param(std::string &xml, const int32_t &param)
+{
+  xml += (boost::format("<param><value><int>%i</int></value></param>") % param).str();
+}
+
+void message_transporter::end_xml_rpc_cmd(std::string &xml)
+{
+  xml += "</params></methodCall>";
+}
+
+}

src/wallet/message_transporter.h

@@ -0,0 +1,113 @@
+// Copyright (c) 2018, 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 "serialization/keyvalue_serialization.h"
+#include "cryptonote_basic/cryptonote_basic.h"
+#include "cryptonote_basic/cryptonote_boost_serialization.h"
+#include "cryptonote_basic/account_boost_serialization.h"
+#include "cryptonote_basic/cryptonote_basic.h"
+#include "net/http_server_impl_base.h"
+#include "net/http_client.h"
+#include "common/util.h"
+#include "wipeable_string.h"
+#include "serialization/keyvalue_serialization.h"
+#include <vector>
+
+namespace mms
+{
+
+struct transport_message
+{
+  cryptonote::account_public_address source_monero_address;
+  std::string source_transport_address;
+  cryptonote::account_public_address destination_monero_address;
+  std::string destination_transport_address;
+  crypto::chacha_iv iv;
+  crypto::public_key encryption_public_key;
+  uint64_t timestamp;
+  uint32_t type;
+  std::string subject;
+  std::string content;
+  crypto::hash hash;
+  crypto::signature signature;
+  uint32_t round;
+  uint32_t signature_count;
+  std::string transport_id;
+
+  BEGIN_KV_SERIALIZE_MAP()
+    KV_SERIALIZE(source_monero_address)
+    KV_SERIALIZE(source_transport_address)
+    KV_SERIALIZE(destination_monero_address)
+    KV_SERIALIZE(destination_transport_address)
+    KV_SERIALIZE_VAL_POD_AS_BLOB(iv)
+    KV_SERIALIZE_VAL_POD_AS_BLOB(encryption_public_key)
+    KV_SERIALIZE(timestamp)
+    KV_SERIALIZE(type)
+    KV_SERIALIZE(subject)
+    KV_SERIALIZE(content)
+    KV_SERIALIZE_VAL_POD_AS_BLOB(hash)
+    KV_SERIALIZE_VAL_POD_AS_BLOB(signature)
+    KV_SERIALIZE(round)
+    KV_SERIALIZE(signature_count)
+    KV_SERIALIZE(transport_id)
+  END_KV_SERIALIZE_MAP()
+};
+
+class message_transporter
+{
+public:
+  message_transporter();
+  void set_options(const std::string &bitmessage_address, const epee::wipeable_string &bitmessage_login);
+  bool send_message(const transport_message &message);
+  bool receive_messages(const std::vector<std::string> &destination_transport_addresses,
+                        std::vector<transport_message> &messages);
+  bool delete_message(const std::string &transport_id);
+  void stop() { m_run.store(false, std::memory_order_relaxed); }
+  std::string derive_transport_address(const std::string &seed);
+  std::string derive_and_receive_transport_address(const std::string &seed);
+  bool delete_transport_address(const std::string &transport_address);
+
+private:
+  epee::net_utils::http::http_simple_client m_http_client;
+  std::string m_bitmessage_url;
+  epee::wipeable_string m_bitmessage_login;
+  std::atomic<bool> m_run;
+
+  bool post_request(const std::string &request, std::string &answer);
+  static std::string get_str_between_tags(const std::string &s, const std::string &start_delim, const std::string &stop_delim);
+
+  static void start_xml_rpc_cmd(std::string &xml, const std::string &method_name);
+  static void add_xml_rpc_string_param(std::string &xml, const std::string &param);
+  static void add_xml_rpc_base64_param(std::string &xml, const std::string &param);
+  static void add_xml_rpc_integer_param(std::string &xml, const int32_t &param);
+  static void end_xml_rpc_cmd(std::string &xml);
+
+};
+
+}

src/wallet/wallet2.cpp

@@ -226,7 +226,7 @@ struct options {
   const command_line::arg_descriptor<std::string> tx_notify = { "tx-notify" , "Run a program for each new incoming transaction, '%s' will be replaced by the transaction hash" , "" };
 };
 
-void do_prepare_file_names(const std::string& file_path, std::string& keys_file, std::string& wallet_file)
+void do_prepare_file_names(const std::string& file_path, std::string& keys_file, std::string& wallet_file, std::string &mms_file)
 {
   keys_file = file_path;
   wallet_file = file_path;
@@ -238,6 +238,7 @@ void do_prepare_file_names(const std::string& file_path, std::string& keys_file,
   {//provided wallet file name
     keys_file += ".keys";
   }
+  mms_file = file_path + ".mms";
 }
 
 uint64_t calculate_fee(uint64_t fee_per_kb, size_t bytes, uint64_t fee_multiplier)
@@ -330,6 +331,7 @@ std::unique_ptr<tools::wallet2> make_basic(const boost::program_options::variabl
   wallet->init(std::move(daemon_address), std::move(login), 0, false, *trusted_daemon);
   boost::filesystem::path ringdb_path = command_line::get_arg(vm, opts.shared_ringdb_dir);
   wallet->set_ring_database(ringdb_path.string());
+  wallet->get_message_store().set_options(vm);
   wallet->device_name(device_name);
   wallet->device_derivation_path(device_derivation_path);
 
@@ -907,6 +909,8 @@ wallet2::wallet2(network_type nettype, uint64_t kdf_rounds, bool unattended):
   m_light_wallet_connected(false),
   m_light_wallet_balance(0),
   m_light_wallet_unlocked_balance(0),
+  m_original_keys_available(false),
+  m_message_store(),
   m_key_device_type(hw::device::device_type::SOFTWARE),
   m_ring_history_saved(false),
   m_ringdb(),
@@ -956,6 +960,7 @@ void wallet2::init_options(boost::program_options::options_description& desc_par
   command_line::add_arg(desc_params, opts.stagenet);
   command_line::add_arg(desc_params, opts.shared_ringdb_dir);
   command_line::add_arg(desc_params, opts.kdf_rounds);
+  mms::message_store::init_options(desc_params);
   command_line::add_arg(desc_params, opts.hw_device);
   command_line::add_arg(desc_params, opts.hw_device_derivation_path);
   command_line::add_arg(desc_params, opts.tx_notify);
@@ -3184,6 +3189,9 @@ bool wallet2::store_keys(const std::string& keys_file_name, const epee::wipeable
   value2.SetUint(m_subaddress_lookahead_minor);
   json.AddMember("subaddress_lookahead_minor", value2, json.GetAllocator());
 
+  value2.SetInt(m_original_keys_available ? 1 : 0);
+  json.AddMember("original_keys_available", value2, json.GetAllocator());
+
   value2.SetUint(1);
   json.AddMember("encrypted_secret_keys", value2, json.GetAllocator());
 
@@ -3193,6 +3201,18 @@ bool wallet2::store_keys(const std::string& keys_file_name, const epee::wipeable
   value.SetString(m_device_derivation_path.c_str(), m_device_derivation_path.size());
   json.AddMember("device_derivation_path", value, json.GetAllocator());
 
+  std::string original_address;
+  std::string original_view_secret_key;
+  if (m_original_keys_available)
+  {  
+    original_address = get_account_address_as_str(m_nettype, false, m_original_address);
+    value.SetString(original_address.c_str(), original_address.length());
+    json.AddMember("original_address", value, json.GetAllocator());
+    original_view_secret_key = epee::string_tools::pod_to_hex(m_original_view_secret_key);
+    value.SetString(original_view_secret_key.c_str(), original_view_secret_key.length());
+    json.AddMember("original_view_secret_key", value, json.GetAllocator());
+  }
+  
   // Serialize the JSON object
   rapidjson::StringBuffer buffer;
   rapidjson::Writer<rapidjson::StringBuffer> writer(buffer);
@@ -3311,6 +3331,7 @@ bool wallet2::load_keys(const std::string& keys_file_name, const epee::wipeable_
     m_ignore_fractional_outputs = true;
     m_subaddress_lookahead_major = SUBADDRESS_LOOKAHEAD_MAJOR;
     m_subaddress_lookahead_minor = SUBADDRESS_LOOKAHEAD_MINOR;
+    m_original_keys_available = false;
     m_device_name = "";
     m_device_derivation_path = "";
     m_key_device_type = hw::device::device_type::SOFTWARE;
@@ -3483,6 +3504,35 @@ bool wallet2::load_keys(const std::string& keys_file_name, const epee::wipeable_
 
     GET_FIELD_FROM_JSON_RETURN_ON_ERROR(json, device_derivation_path, std::string, String, false, std::string());
     m_device_derivation_path = field_device_derivation_path;
+    
+    if (json.HasMember("original_keys_available"))
+    {
+      GET_FIELD_FROM_JSON_RETURN_ON_ERROR(json, original_keys_available, int, Int, false, false);
+      m_original_keys_available = field_original_keys_available;
+      if (m_original_keys_available)
+      {
+        GET_FIELD_FROM_JSON_RETURN_ON_ERROR(json, original_address, std::string, String, true, std::string());
+        address_parse_info info;
+        bool ok = get_account_address_from_str(info, m_nettype, field_original_address);
+        if (!ok)
+        {
+          LOG_ERROR("Failed to parse original_address from JSON");
+          return false;
+        }
+        m_original_address = info.address;
+        GET_FIELD_FROM_JSON_RETURN_ON_ERROR(json, original_view_secret_key, std::string, String, true, std::string());
+        ok = epee::string_tools::hex_to_pod(field_original_view_secret_key, m_original_view_secret_key);
+        if (!ok)
+        {
+          LOG_ERROR("Failed to parse original_view_secret_key from JSON");
+          return false;
+        }
+      }
+    }
+    else
+    {
+      m_original_keys_available = false;
+    }
   }
   else
   {
@@ -3809,6 +3859,10 @@ void wallet2::generate(const std::string& wallet_, const epee::wipeable_string&
   m_key_device_type = hw::device::device_type::SOFTWARE;
   setup_keys(password);
 
+  // Not possible to restore a multisig wallet that is able to activate the MMS
+  // (because the original keys are not (yet) part of the restore info)
+  m_original_keys_available = false;
+
   create_keys_file(wallet_, false, password, m_nettype != MAINNET || create_address_file);
   setup_new_blockchain();
 
@@ -3846,6 +3900,7 @@ crypto::secret_key wallet2::generate(const std::string& wallet_, const epee::wip
   m_multisig = false;
   m_multisig_threshold = 0;
   m_multisig_signers.clear();
+  m_original_keys_available = false;
   m_key_device_type = hw::device::device_type::SOFTWARE;
   setup_keys(password);
 
@@ -3934,6 +3989,7 @@ void wallet2::generate(const std::string& wallet_, const epee::wipeable_string&
   m_multisig = false;
   m_multisig_threshold = 0;
   m_multisig_signers.clear();
+  m_original_keys_available = false;
   m_key_device_type = hw::device::device_type::SOFTWARE;
   setup_keys(password);
 
@@ -3974,6 +4030,7 @@ void wallet2::generate(const std::string& wallet_, const epee::wipeable_string&
   m_multisig = false;
   m_multisig_threshold = 0;
   m_multisig_signers.clear();
+  m_original_keys_available = false;
   m_key_device_type = hw::device::device_type::SOFTWARE;
   setup_keys(password);
 
@@ -4015,6 +4072,7 @@ void wallet2::restore(const std::string& wallet_, const epee::wipeable_string& p
   m_multisig = false;
   m_multisig_threshold = 0;
   m_multisig_signers.clear();
+  m_original_keys_available = false;
   setup_keys(password);
   m_device_name = device_name;
 
@@ -4127,6 +4185,15 @@ std::string wallet2::make_multisig(const epee::wipeable_string &password,
       m_multisig_derivations = derivations;
     }
   }
+  
+  if (!m_original_keys_available)
+  {
+    // Save the original i.e. non-multisig keys so the MMS can continue to use them to encrypt and decrypt messages
+    // (making a wallet multisig overwrites those keys, see account_base::make_multisig)
+    m_original_address = m_account.get_keys().m_account_address;
+    m_original_view_secret_key = m_account.get_keys().m_view_secret_key;
+    m_original_keys_available = true;
+  }
 
   clear();
   MINFO("Creating view key...");
@@ -4560,8 +4627,8 @@ void wallet2::write_watch_only_wallet(const std::string& wallet_name, const epee
 //----------------------------------------------------------------------------------------------------
 void wallet2::wallet_exists(const std::string& file_path, bool& keys_file_exists, bool& wallet_file_exists)
 {
-  std::string keys_file, wallet_file;
-  do_prepare_file_names(file_path, keys_file, wallet_file);
+  std::string keys_file, wallet_file, mms_file;
+  do_prepare_file_names(file_path, keys_file, wallet_file, mms_file);
 
   boost::system::error_code ignore;
   keys_file_exists = boost::filesystem::exists(keys_file, ignore);
@@ -4615,7 +4682,7 @@ bool wallet2::parse_payment_id(const std::string& payment_id_str, crypto::hash&
 //----------------------------------------------------------------------------------------------------
 bool wallet2::prepare_file_names(const std::string& file_path)
 {
-  do_prepare_file_names(file_path, m_keys_file, m_wallet_file);
+  do_prepare_file_names(file_path, m_keys_file, m_wallet_file, m_mms_file);
   return true;
 }
 //----------------------------------------------------------------------------------------------------
@@ -4808,6 +4875,8 @@ void wallet2::load(const std::string& wallet_, const epee::wipeable_string& pass
   {
     MERROR("Failed to save rings, will try again next time");
   }
+  
+  m_message_store.read_from_file(get_multisig_wallet_state(), m_mms_file);
 }
 //----------------------------------------------------------------------------------------------------
 void wallet2::trim_hashchain()
@@ -4913,6 +4982,7 @@ void wallet2::store_to(const std::string &path, const epee::wipeable_string &pas
   const std::string old_file = m_wallet_file;
   const std::string old_keys_file = m_keys_file;
   const std::string old_address_file = m_wallet_file + ".address.txt";
+  const std::string old_mms_file = m_mms_file;
 
   // save keys to the new file
   // if we here, main wallet file is saved and we only need to save keys and address files
@@ -4942,6 +5012,14 @@ void wallet2::store_to(const std::string &path, const epee::wipeable_string &pas
     if (!r) {
       LOG_ERROR("error removing file: " << old_address_file);
     }
+    // remove old message store file
+    if (boost::filesystem::exists(old_mms_file))
+    {
+      r = boost::filesystem::remove(old_mms_file);
+      if (!r) {
+        LOG_ERROR("error removing file: " << old_mms_file);
+      }
+    }
   } else {
     // save to new file
 #ifdef WIN32
@@ -4967,6 +5045,14 @@ void wallet2::store_to(const std::string &path, const epee::wipeable_string &pas
     std::error_code e = tools::replace_file(new_file, m_wallet_file);
     THROW_WALLET_EXCEPTION_IF(e, error::file_save_error, m_wallet_file, e);
   }
+  
+  if (m_message_store.get_active())
+  {
+    // While the "m_message_store" object of course always exist, a file for the message
+    // store should only exist if the MMS is really active
+    m_message_store.write_to_file(get_multisig_wallet_state(), m_mms_file);
+  }
+  
 }
 //----------------------------------------------------------------------------------------------------
 uint64_t wallet2::balance(uint32_t index_major) const
@@ -12030,6 +12116,29 @@ void wallet2::generate_genesis(cryptonote::block& b) const {
   cryptonote::generate_genesis_block(b, get_config(m_nettype).GENESIS_TX, get_config(m_nettype).GENESIS_NONCE);
 }
 //----------------------------------------------------------------------------------------------------
+mms::multisig_wallet_state wallet2::get_multisig_wallet_state() const
+{
+  mms::multisig_wallet_state state;
+  state.nettype = m_nettype;
+  state.multisig = multisig(&state.multisig_is_ready);
+  state.has_multisig_partial_key_images = has_multisig_partial_key_images();
+  state.multisig_rounds_passed = m_multisig_rounds_passed;
+  state.num_transfer_details = m_transfers.size();
+  if (state.multisig)
+  {
+    THROW_WALLET_EXCEPTION_IF(!m_original_keys_available, error::wallet_internal_error, "MMS use not possible because own original Monero address not available");
+    state.address = m_original_address;
+    state.view_secret_key = m_original_view_secret_key;
+  }
+  else
+  {
+    state.address = m_account.get_keys().m_account_address;
+    state.view_secret_key = m_account.get_keys().m_view_secret_key;
+  }
+  state.mms_file=m_mms_file;
+  return state;
+}
+//----------------------------------------------------------------------------------------------------
 wallet_device_callback * wallet2::get_device_callback()
 {
   if (!m_device_callback){

src/wallet/wallet2.h

@@ -61,6 +61,7 @@
 #include "wallet_errors.h"
 #include "common/password.h"
 #include "node_rpc_proxy.h"
+#include "message_store.h"
 
 #undef MONERO_DEFAULT_LOG_CATEGORY
 #define MONERO_DEFAULT_LOG_CATEGORY "wallet.wallet2"
@@ -674,7 +675,7 @@ namespace tools
     bool init(std::string daemon_address = "http://localhost:8080",
       boost::optional<epee::net_utils::http::login> daemon_login = boost::none, uint64_t upper_transaction_weight_limit = 0, bool ssl = false, bool trusted_daemon = false);
 
-    void stop() { m_run.store(false, std::memory_order_relaxed); }
+    void stop() { m_run.store(false, std::memory_order_relaxed); m_message_store.stop(); }
 
     i_wallet2_callback* callback() const { return m_callback; }
     void callback(i_wallet2_callback* callback) { m_callback = callback; }
@@ -1218,6 +1219,11 @@ namespace tools
     bool unblackball_output(const std::pair<uint64_t, uint64_t> &output);
     bool is_output_blackballed(const std::pair<uint64_t, uint64_t> &output) const;
 
+    // MMS -------------------------------------------------------------------------------------------------
+    mms::message_store& get_message_store() { return m_message_store; };
+    const mms::message_store& get_message_store() const { return m_message_store; };
+    mms::multisig_wallet_state get_multisig_wallet_state() const;
+
     bool lock_keys_file();
     bool unlock_keys_file();
     bool is_keys_file_locked() const;
@@ -1320,6 +1326,7 @@ namespace tools
     std::string m_daemon_address;
     std::string m_wallet_file;
     std::string m_keys_file;
+    std::string m_mms_file;
     epee::net_utils::http::http_simple_client m_http_client;
     hashchain m_blockchain;
     std::unordered_map<crypto::hash, unconfirmed_transfer_details> m_unconfirmed_txs;
@@ -1420,6 +1427,11 @@ namespace tools
 
     uint64_t m_last_block_reward;
     std::unique_ptr<tools::file_locker> m_keys_file_locker;
+    
+    mms::message_store m_message_store;
+    bool m_original_keys_available;
+    cryptonote::account_public_address m_original_address;
+    crypto::secret_key m_original_view_secret_key;
 
     crypto::chacha_key m_cache_key;
     boost::optional<epee::wipeable_string> m_encrypt_keys_after_refresh;

src/wallet/wallet_errors.h

@@ -821,6 +821,31 @@ namespace tools
       std::string m_wallet_file;
     };
     //----------------------------------------------------------------------------------------------------
+    struct mms_error : public wallet_logic_error
+    {
+    protected:
+      explicit mms_error(std::string&& loc, const std::string& message)
+        : wallet_logic_error(std::move(loc), message)
+      {
+      }
+    };
+    //----------------------------------------------------------------------------------------------------
+    struct no_connection_to_bitmessage : public mms_error
+    {
+      explicit no_connection_to_bitmessage(std::string&& loc, const std::string& address)
+        : mms_error(std::move(loc), "no connection to PyBitmessage at address " + address)
+      {
+      }
+    };
+    //----------------------------------------------------------------------------------------------------
+    struct bitmessage_api_error : public mms_error
+    {
+      explicit bitmessage_api_error(std::string&& loc, const std::string& error_string)
+        : mms_error(std::move(loc), "PyBitmessage returned " + error_string)
+      {
+      }
+    };
+    //----------------------------------------------------------------------------------------------------
 
 #if !defined(_MSC_VER)