Merge pull request #8942

78348bc wallet-rpc: restore from multisig seed (jeffro256)

7 files changed, 217 insertions, 35 deletions

diff --git a/contrib/epee/include/span.h b/contrib/epee/include/span.h
index 99c2ebb4f..23bd51f8c 100644
--- a/contrib/epee/include/span.h
+++ b/contrib/epee/include/span.h
@@ -147,6 +147,16 @@ namespace epee
     return {reinterpret_cast<const std::uint8_t*>(src.data()), src.size_bytes()}; 
   }
 
+  //! \return `span<std::uint8_t>` from a STL compatible `src`.
+  template<typename T>
+  constexpr span<std::uint8_t> to_mut_byte_span(T& src)
+  {
+    using value_type = typename T::value_type;
+    static_assert(!std::is_empty<value_type>(), "empty value types will not work -> sizeof == 1");
+    static_assert(!has_padding<value_type>(), "source value type may have padding");
+    return {reinterpret_cast<std::uint8_t*>(src.data()), src.size() * sizeof(value_type)};
+  }
+
   //! \return `span<const std::uint8_t>` which represents the bytes at `&src`.
   template<typename T>
   span<const std::uint8_t> as_byte_span(const T& src) noexcept
diff --git a/src/wallet/wallet2.cpp b/src/wallet/wallet2.cpp
index 1ea699ef1..df34e441f 100644
--- a/src/wallet/wallet2.cpp
+++ b/src/wallet/wallet2.cpp
@@ -988,6 +988,21 @@ bool get_pruned_tx(const cryptonote::COMMAND_RPC_GET_TRANSACTIONS::entry &entry,
   return false;
 }
 
+// Given M (threshold) and N (total), calculate the number of private multisig keys each
+// signer should have. This value is equal to (N - 1) choose (N - M)
+// Prereq: M >= 1 && N >= M && N <= 16
+uint64_t num_priv_multisig_keys_post_setup(uint64_t threshold, uint64_t total)
+{
+  THROW_WALLET_EXCEPTION_IF(threshold < 1 || total < threshold || threshold > 16,
+    tools::error::wallet_internal_error, "Invalid arguments to num_priv_multisig_keys_post_setup");
+
+  uint64_t n_multisig_keys = 1;
+  for (uint64_t i = 2; i <= total - 1; ++i) n_multisig_keys *= i; // multiply by (N - 1)!
+  for (uint64_t i = 2; i <= total - threshold; ++i) n_multisig_keys /= i; // divide by (N - M)!
+  for (uint64_t i = 2; i <= threshold - 1; ++i) n_multisig_keys /= i; // divide by ((N - 1) - (N - M))!
+  return n_multisig_keys;
+}
+
   //-----------------------------------------------------------------
 } //namespace
 
@@ -1412,7 +1427,7 @@ bool wallet2::get_seed(epee::wipeable_string& electrum_words, const epee::wipeab
   return true;
 }
 //----------------------------------------------------------------------------------------------------
-bool wallet2::get_multisig_seed(epee::wipeable_string& seed, const epee::wipeable_string &passphrase, bool raw) const
+bool wallet2::get_multisig_seed(epee::wipeable_string& seed, const epee::wipeable_string &passphrase) const
 {
   bool ready;
   uint32_t threshold, total;
@@ -1426,15 +1441,14 @@ bool wallet2::get_multisig_seed(epee::wipeable_string& seed, const epee::wipeabl
     std::cout << "This multisig wallet is not yet finalized" << std::endl;
     return false;
   }
-  if (!raw && seed_language.empty())
-  {
-    std::cout << "seed_language not set" << std::endl;
-    return false;
-  }
+
+  const uint64_t num_expected_ms_keys = num_priv_multisig_keys_post_setup(threshold, total);
 
   crypto::secret_key skey;
   crypto::public_key pkey;
   const account_keys &keys = get_account().get_keys();
+  THROW_WALLET_EXCEPTION_IF(num_expected_ms_keys != keys.m_multisig_keys.size(),
+    error::wallet_internal_error, "Unexpected number of private multisig keys")
   epee::wipeable_string data;
   data.append((const char*)&threshold, sizeof(uint32_t));
   data.append((const char*)&total, sizeof(uint32_t));
@@ -1459,18 +1473,7 @@ bool wallet2::get_multisig_seed(epee::wipeable_string& seed, const epee::wipeabl
     data = encrypt(data, key, true);
   }
 
-  if (raw)
-  {
-    seed = epee::to_hex::wipeable_string({(const unsigned char*)data.data(), data.size()});
-  }
-  else
-  {
-    if (!crypto::ElectrumWords::bytes_to_words(data.data(), data.size(), seed, seed_language))
-    {
-      std::cout << "Failed to encode seed";
-      return false;
-    }
-  }
+  seed = epee::to_hex::wipeable_string({(const unsigned char*)data.data(), data.size()});
 
   return true;
 }
@@ -5280,9 +5283,11 @@ void wallet2::generate(const std::string& wallet_, const epee::wipeable_string&
   offset += sizeof(uint32_t);
   uint32_t total = *(uint32_t*)(multisig_data.data() + offset);
   offset += sizeof(uint32_t);
-  THROW_WALLET_EXCEPTION_IF(threshold < 2, error::invalid_multisig_seed);
-  THROW_WALLET_EXCEPTION_IF(total != threshold && total != threshold + 1, error::invalid_multisig_seed);
-  const size_t n_multisig_keys =  total == threshold ? 1 : threshold;
+
+  THROW_WALLET_EXCEPTION_IF(threshold < 1, error::invalid_multisig_seed);
+  THROW_WALLET_EXCEPTION_IF(total < threshold, error::invalid_multisig_seed);
+  THROW_WALLET_EXCEPTION_IF(threshold > 16, error::invalid_multisig_seed); // doing N choose (N - M + 1) might overflow
+  const uint64_t n_multisig_keys = num_priv_multisig_keys_post_setup(threshold, total);
   THROW_WALLET_EXCEPTION_IF(multisig_data.size() != 8 + 32 * (4 + n_multisig_keys + total), error::invalid_multisig_seed);
 
   std::vector<crypto::secret_key> multisig_keys;
diff --git a/src/wallet/wallet2.h b/src/wallet/wallet2.h
index f07e1c41a..baeffe096 100644
--- a/src/wallet/wallet2.h
+++ b/src/wallet/wallet2.h
@@ -1059,7 +1059,7 @@ private:
     bool multisig(bool *ready = NULL, uint32_t *threshold = NULL, uint32_t *total = NULL) const;
     bool has_multisig_partial_key_images() const;
     bool has_unknown_key_images() const;
-    bool get_multisig_seed(epee::wipeable_string& seed, const epee::wipeable_string &passphrase = std::string(), bool raw = true) const;
+    bool get_multisig_seed(epee::wipeable_string& seed, const epee::wipeable_string &passphrase = std::string()) const;
     bool key_on_device() const { return get_device_type() != hw::device::device_type::SOFTWARE; }
     hw::device::device_type get_device_type() const { return m_key_device_type; }
     bool reconnect_device();
diff --git a/src/wallet/wallet_rpc_server.cpp b/src/wallet/wallet_rpc_server.cpp
index 4f1b3bd21..8119d9d09 100644
--- a/src/wallet/wallet_rpc_server.cpp
+++ b/src/wallet/wallet_rpc_server.cpp
@@ -3808,7 +3808,7 @@ namespace tools
     std::string old_language;
 
     // check the given seed
-    {
+    if (!req.enable_multisig_experimental) {
       if (!crypto::ElectrumWords::words_to_bytes(req.seed, recovery_key, old_language))
       {
         er.code = WALLET_RPC_ERROR_CODE_UNKNOWN_ERROR;
@@ -3831,6 +3831,13 @@ namespace tools
 
     // process seed_offset if given
     {
+      if (req.enable_multisig_experimental && !req.seed_offset.empty())
+      {
+        er.code = WALLET_RPC_ERROR_CODE_UNKNOWN_ERROR;
+        er.message = "Multisig seeds are not compatible with seed offsets";
+        return false;
+      }
+
       if (!req.seed_offset.empty())
       {
         recovery_key = cryptonote::decrypt_key(recovery_key, req.seed_offset);
@@ -3894,7 +3901,27 @@ namespace tools
     crypto::secret_key recovery_val;
     try
     {
-      recovery_val = wal->generate(wallet_file, std::move(rc.second).password(), recovery_key, true, false, false);
+      if (req.enable_multisig_experimental)
+      {
+        // Parse multisig seed into raw multisig data
+        epee::wipeable_string multisig_data;
+        multisig_data.resize(req.seed.size() / 2);
+        if (!epee::from_hex::to_buffer(epee::to_mut_byte_span(multisig_data), req.seed))
+        {
+          er.code = WALLET_RPC_ERROR_CODE_UNKNOWN_ERROR;
+          er.message = "Multisig seed not represented as hexadecimal string";
+          return false;
+        }
+
+        // Generate multisig wallet
+        wal->generate(wallet_file, std::move(rc.second).password(), multisig_data, false);
+        wal->enable_multisig(true);
+      }
+      else
+      {
+        // Generate normal wallet
+        recovery_val = wal->generate(wallet_file, std::move(rc.second).password(), recovery_key, true, false, false);
+      }
       MINFO("Wallet has been restored.\n");
     }
     catch (const std::exception &e)
@@ -3905,7 +3932,7 @@ namespace tools
 
     // // Convert the secret key back to seed
     epee::wipeable_string electrum_words;
-    if (!crypto::ElectrumWords::bytes_to_words(recovery_val, electrum_words, mnemonic_language))
+    if (!req.enable_multisig_experimental && !crypto::ElectrumWords::bytes_to_words(recovery_val, electrum_words, mnemonic_language))
     {
       er.code = WALLET_RPC_ERROR_CODE_UNKNOWN_ERROR;
       er.message = "Failed to encode seed";
diff --git a/src/wallet/wallet_rpc_server_commands_defs.h b/src/wallet/wallet_rpc_server_commands_defs.h
index 74c3862cb..d5c6bfd6b 100644
--- a/src/wallet/wallet_rpc_server_commands_defs.h
+++ b/src/wallet/wallet_rpc_server_commands_defs.h
@@ -2262,6 +2262,7 @@ namespace wallet_rpc
       std::string password;
       std::string language;
       bool autosave_current;
+      bool enable_multisig_experimental;
 
       BEGIN_KV_SERIALIZE_MAP()
       KV_SERIALIZE_OPT(restore_height, (uint64_t)0)
@@ -2271,6 +2272,7 @@ namespace wallet_rpc
       KV_SERIALIZE(password)
       KV_SERIALIZE(language)
       KV_SERIALIZE_OPT(autosave_current, true)
+      KV_SERIALIZE_OPT(enable_multisig_experimental, false)
       END_KV_SERIALIZE_MAP()
     };
     typedef epee::misc_utils::struct_init<request_t> request;
diff --git a/tests/functional_tests/multisig.py b/tests/functional_tests/multisig.py
index 59f124e00..980adc2df 100755
--- a/tests/functional_tests/multisig.py
+++ b/tests/functional_tests/multisig.py
@@ -29,6 +29,7 @@
 # THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 from __future__ import print_function
+import random
 
 """Test multisig transfers
 """
@@ -36,42 +37,74 @@ from __future__ import print_function
 from framework.daemon import Daemon
 from framework.wallet import Wallet
 
+MULTISIG_PUB_ADDRS = [
+  '45J58b7PmKJFSiNPFFrTdtfMcFGnruP7V4CMuRpX7NsH4j3jGHKAjo3YJP2RePX6HMaSkbvTbrWUFhDNcNcHgtNmQ3gr7sG', # 2/2
+  '44G2TQNfsiURKkvxp7gbgaJY8WynZvANnhmyMAwv6WeEbAvyAWMfKXRhh3uBXT2UAKhAsUJ7Fg5zjjF2U1iGciFk5duN94i', # 2/3
+  '41mro238grj56GnrWkakAKTkBy2yDcXYsUZ2iXCM9pe5Ueajd2RRc6Fhh3uBXT2UAKhAsUJ7Fg5zjjF2U1iGciFk5ief4ZP', # 3/3
+  '44vZSprQKJQRFe6t1VHgU4ESvq2dv7TjBLVGE7QscKxMdFSiyyPCEV64NnKUQssFPyWxc2meyt7j63F2S2qtCTRL6dakeff', # 3/4
+  '47puypSwsV1gvUDratmX4y58fSwikXVehEiBhVLxJA1gRCxHyrRgTDr4NnKUQssFPyWxc2meyt7j63F2S2qtCTRL6aRPj5U', # 2/4
+  '4A8RnBQixry4VXkqeWhmg8L7vWJVDJj4FN9PV4E7Mgad5ZZ6LKQdn8dYJP2RePX6HMaSkbvTbrWUFhDNcNcHgtNmQ4S8RSB'  # 1/2
+]
+
 class MultisigTest():
     def run_test(self):
         self.reset()
-        self.mine('45J58b7PmKJFSiNPFFrTdtfMcFGnruP7V4CMuRpX7NsH4j3jGHKAjo3YJP2RePX6HMaSkbvTbrWUFhDNcNcHgtNmQ3gr7sG', 5)
-        self.mine('44G2TQNfsiURKkvxp7gbgaJY8WynZvANnhmyMAwv6WeEbAvyAWMfKXRhh3uBXT2UAKhAsUJ7Fg5zjjF2U1iGciFk5duN94i', 5)
-        self.mine('41mro238grj56GnrWkakAKTkBy2yDcXYsUZ2iXCM9pe5Ueajd2RRc6Fhh3uBXT2UAKhAsUJ7Fg5zjjF2U1iGciFk5ief4ZP', 5)
-        self.mine('44vZSprQKJQRFe6t1VHgU4ESvq2dv7TjBLVGE7QscKxMdFSiyyPCEV64NnKUQssFPyWxc2meyt7j63F2S2qtCTRL6dakeff', 5)
-        self.mine('47puypSwsV1gvUDratmX4y58fSwikXVehEiBhVLxJA1gRCxHyrRgTDr4NnKUQssFPyWxc2meyt7j63F2S2qtCTRL6aRPj5U', 5)
+        for pub_addr in MULTISIG_PUB_ADDRS:
+          self.mine(pub_addr, 4)
         self.mine('42ey1afDFnn4886T7196doS9GPMzexD9gXpsZJDwVjeRVdFCSoHnv7KPbBeGpzJBzHRCAs9UxqeoyFQMYbqSWYTfJJQAWDm', 80)
 
         self.test_states()
 
+        self.fund_addrs_with_normal_wallet(MULTISIG_PUB_ADDRS)
+
         self.create_multisig_wallets(2, 2, '45J58b7PmKJFSiNPFFrTdtfMcFGnruP7V4CMuRpX7NsH4j3jGHKAjo3YJP2RePX6HMaSkbvTbrWUFhDNcNcHgtNmQ3gr7sG')
         self.import_multisig_info([1, 0], 5)
         txid = self.transfer([1, 0])
         self.import_multisig_info([0, 1], 6)
         self.check_transaction(txid)
 
+        self.remake_some_multisig_wallets_by_multsig_seed(2)
+        self.import_multisig_info([0, 1], 6) # six outputs, same as before
+        txid = self.transfer([0, 1])
+        self.import_multisig_info([0, 1], 7) # seven outputs b/c we're dest plus change
+        self.check_transaction(txid)
+
         self.create_multisig_wallets(2, 3, '44G2TQNfsiURKkvxp7gbgaJY8WynZvANnhmyMAwv6WeEbAvyAWMfKXRhh3uBXT2UAKhAsUJ7Fg5zjjF2U1iGciFk5duN94i')
         self.import_multisig_info([0, 2], 5)
         txid = self.transfer([0, 2])
         self.import_multisig_info([0, 1, 2], 6)
         self.check_transaction(txid)
 
+        self.remake_some_multisig_wallets_by_multsig_seed(2)
+        self.import_multisig_info([0, 2], 6) # six outputs, same as before
+        txid = self.transfer([0, 2])
+        self.import_multisig_info([0, 1, 2], 7) # seven outputs b/c we're dest plus change
+        self.check_transaction(txid)
+
         self.create_multisig_wallets(3, 3, '41mro238grj56GnrWkakAKTkBy2yDcXYsUZ2iXCM9pe5Ueajd2RRc6Fhh3uBXT2UAKhAsUJ7Fg5zjjF2U1iGciFk5ief4ZP')
         self.import_multisig_info([2, 0, 1], 5)
         txid = self.transfer([2, 1, 0])
         self.import_multisig_info([0, 2, 1], 6)
         self.check_transaction(txid)
 
+        self.remake_some_multisig_wallets_by_multsig_seed(3)
+        self.import_multisig_info([2, 0, 1], 6) # six outputs, same as before
+        txid = self.transfer([2, 1, 0])
+        self.import_multisig_info([0, 2, 1], 7) # seven outputs b/c we're dest plus change
+        self.check_transaction(txid)
+
         self.create_multisig_wallets(3, 4, '44vZSprQKJQRFe6t1VHgU4ESvq2dv7TjBLVGE7QscKxMdFSiyyPCEV64NnKUQssFPyWxc2meyt7j63F2S2qtCTRL6dakeff')
         self.import_multisig_info([0, 2, 3], 5)
         txid = self.transfer([0, 2, 3])
         self.import_multisig_info([0, 1, 2, 3], 6)
         self.check_transaction(txid)
 
+        self.remake_some_multisig_wallets_by_multsig_seed(3)
+        self.import_multisig_info([0, 2, 3], 6) # six outputs, same as before
+        txid = self.transfer([0, 2, 3])
+        self.import_multisig_info([0, 1, 2, 3], 7) # seven outputs b/c we're dest plus change
+        self.check_transaction(txid)
+
         self.create_multisig_wallets(2, 4, '47puypSwsV1gvUDratmX4y58fSwikXVehEiBhVLxJA1gRCxHyrRgTDr4NnKUQssFPyWxc2meyt7j63F2S2qtCTRL6aRPj5U')
         self.import_multisig_info([1, 2], 5)
         txid = self.transfer([1, 2])
@@ -81,6 +114,24 @@ class MultisigTest():
         self.import_multisig_info([0, 1, 2, 3], 7)
         self.check_transaction(txid)
 
+        self.remake_some_multisig_wallets_by_multsig_seed(2)
+        self.import_multisig_info([0, 1, 2, 3], 6) # six outputs, same as before
+        txid = self.transfer([2, 3])
+        self.import_multisig_info([0, 1, 2, 3], 7) # seven outputs b/c we're dest plus change
+        self.check_transaction(txid)
+
+        self.create_multisig_wallets(1, 2, '4A8RnBQixry4VXkqeWhmg8L7vWJVDJj4FN9PV4E7Mgad5ZZ6LKQdn8dYJP2RePX6HMaSkbvTbrWUFhDNcNcHgtNmQ4S8RSB')
+        self.import_multisig_info([0, 1], 5)
+        txid = self.transfer([0])
+        self.import_multisig_info([0, 1], 6)
+        self.check_transaction(txid)
+
+        self.remake_some_multisig_wallets_by_multsig_seed(1)
+        self.import_multisig_info([0, 1], 6) # six outputs, same as before
+        txid = self.transfer([1])
+        self.import_multisig_info([0, 1], 7) # seven outputs b/c we're dest plus change
+        self.check_transaction(txid)
+
     def reset(self):
         print('Resetting blockchain')
         daemon = Daemon()
@@ -93,6 +144,11 @@ class MultisigTest():
         daemon = Daemon()
         daemon.generateblocks(address, blocks)
 
+    # This method sets up N_total wallets with a threshold of M_threshold doing the following steps:
+    #   * restore_deterministic_wallet(w/ hardcoded seeds)
+    #   * prepare_multisig(enable_multisig_experimental = True)
+    #   * make_multisig()
+    #   * exchange_multisig_keys()
     def create_multisig_wallets(self, M_threshold, N_total, expected_address):
       print('Creating ' + str(M_threshold) + '/' + str(N_total) + ' multisig wallet')
       seeds = [
@@ -103,6 +159,8 @@ class MultisigTest():
       ]
       assert M_threshold <= N_total
       assert N_total <= len(seeds)
+
+      # restore_deterministic_wallet() & prepare_multisig()
       self.wallet = [None] * N_total
       info = []
       for i in range(N_total):
@@ -114,10 +172,12 @@ class MultisigTest():
         assert len(res.multisig_info) > 0
         info.append(res.multisig_info)
 
+      # Assert that all wallets are multisig
       for i in range(N_total):
         res = self.wallet[i].is_multisig()
         assert res.multisig == False
 
+      # make_multisig() with each other's info
       addresses = []
       next_stage = []
       for i in range(N_total):
@@ -125,6 +185,7 @@ class MultisigTest():
         addresses.append(res.address)
         next_stage.append(res.multisig_info)
 
+      # Assert multisig paramaters M/N for each wallet
       for i in range(N_total):
         res = self.wallet[i].is_multisig()
         assert res.multisig == True
@@ -132,13 +193,15 @@ class MultisigTest():
         assert res.threshold == M_threshold
         assert res.total == N_total
 
-      while True:
+      # exchange_multisig_keys()
+      num_exchange_multisig_keys_stages = 0
+      while True: # while not all wallets are ready
         n_ready = 0
         for i in range(N_total):
           res = self.wallet[i].is_multisig()
           if res.ready == True:
             n_ready += 1
-        assert n_ready == 0 or n_ready == N_total
+        assert n_ready == 0 or n_ready == N_total # No partial readiness
         if n_ready == N_total:
           break
         info = next_stage
@@ -148,10 +211,17 @@ class MultisigTest():
           res = self.wallet[i].exchange_multisig_keys(info)
           next_stage.append(res.multisig_info)
           addresses.append(res.address)
+        num_exchange_multisig_keys_stages += 1
+
+      # We should only need N - M + 1 key exchange rounds
+      assert num_exchange_multisig_keys_stages == N_total - M_threshold + 1
+
+      # Assert that the all wallets have expected public address
       for i in range(N_total):
-        assert addresses[i] == expected_address
+        assert addresses[i] == expected_address, addresses[i]
       self.wallet_address = expected_address
 
+      # Assert multisig paramaters M/N and "ready" for each wallet
       for i in range(N_total):
         res = self.wallet[i].is_multisig()
         assert res.multisig == True
@@ -159,6 +229,73 @@ class MultisigTest():
         assert res.threshold == M_threshold
         assert res.total == N_total
 
+    # We want to test if multisig wallets can receive normal transfers as well and mining transfers
+    def fund_addrs_with_normal_wallet(self, addrs):
+      print("Funding multisig wallets with normal wallet-to-wallet transfers")
+
+      # Generate normal deterministic wallet
+      normal_seed = 'velvet lymph giddy number token physics poetry unquoted nibs useful sabotage limits benches lifestyle eden nitrogen anvil fewest avoid batch vials washing fences goat unquoted'
+      assert not hasattr(self, 'wallet') or not self.wallet
+      self.wallet = [Wallet(idx = 0)]
+      res = self.wallet[0].restore_deterministic_wallet(seed = normal_seed)
+      assert res.address == '42ey1afDFnn4886T7196doS9GPMzexD9gXpsZJDwVjeRVdFCSoHnv7KPbBeGpzJBzHRCAs9UxqeoyFQMYbqSWYTfJJQAWDm'
+
+      self.wallet[0].refresh()
+
+      # Check that we own enough spendable enotes
+      res = self.wallet[0].incoming_transfers(transfer_type = 'available')
+      assert 'transfers' in res
+      num_outs_spendable = 0
+      min_out_amount = None
+      for t in res.transfers:
+          if not t.spent:
+            num_outs_spendable += 1
+            min_out_amount = min(min_out_amount, t.amount) if min_out_amount is not None else t.amount
+      assert num_outs_spendable >= 2 * len(addrs)
+
+      # Transfer to addrs and mine to confirm tx
+      dsts = [{'address': addr, 'amount': int(min_out_amount * 0.95)} for addr in addrs]
+      res = self.wallet[0].transfer(dsts, get_tx_metadata = True)
+      tx_hex = res.tx_metadata
+      res = self.wallet[0].relay_tx(tx_hex)
+      self.mine('42ey1afDFnn4886T7196doS9GPMzexD9gXpsZJDwVjeRVdFCSoHnv7KPbBeGpzJBzHRCAs9UxqeoyFQMYbqSWYTfJJQAWDm', 10)
+
+    def remake_some_multisig_wallets_by_multsig_seed(self, threshold):
+      N = len(self.wallet)
+      signers_to_remake = set()
+      num_signers_to_remake = random.randint(1, N) # Do at least one
+      while len(signers_to_remake) < num_signers_to_remake:
+        signers_to_remake.add(random.randint(0, N - 1))
+
+      for i in signers_to_remake:
+        print("Remaking {}/{} multsig wallet from multisig seed: #{}".format(threshold, N, i+1))
+
+        otherwise_unused_seed = \
+          'factual wiggle awakened maul sash biscuit pause reinvest fonts sleepless knowledge tossed jewels request gusts dagger gumball onward dotted amended powder cynical strained topic request'
+
+        # Get information about wallet, will compare against later
+        old_viewkey = self.wallet[i].query_key('view_key').key
+        old_spendkey = self.wallet[i].query_key('spend_key').key
+        old_multisig_seed = self.wallet[i].query_key('mnemonic').key
+
+        # Close old wallet and restore w/ random seed so we know that restoring actually did something
+        self.wallet[i].close_wallet()
+        self.wallet[i].restore_deterministic_wallet(seed=otherwise_unused_seed)
+        mid_viewkey = self.wallet[i].query_key('view_key').key
+        assert mid_viewkey != old_viewkey
+
+        # Now restore w/ old multisig seed and check against original
+        self.wallet[i].close_wallet()
+        self.wallet[i].restore_deterministic_wallet(seed=old_multisig_seed, enable_multisig_experimental=True)
+        new_viewkey = self.wallet[i].query_key('view_key').key
+        new_spendkey = self.wallet[i].query_key('spend_key').key
+        new_multisig_seed = self.wallet[i].query_key('mnemonic').key
+        assert new_viewkey == old_viewkey
+        assert new_spendkey == old_spendkey
+        assert new_multisig_seed == old_multisig_seed
+
+        self.wallet[i].refresh()
+
     def test_states(self):
         print('Testing multisig states')
         seeds = [
@@ -251,7 +388,7 @@ class MultisigTest():
           assert res.n_outputs == expected_outputs
 
     def transfer(self, signers):
-        assert len(signers) >= 2
+        assert len(signers) >= 1
 
         daemon = Daemon()
 
diff --git a/utils/python-rpc/framework/wallet.py b/utils/python-rpc/framework/wallet.py
index 0f6db76bd..37e91034b 100644
--- a/utils/python-rpc/framework/wallet.py
+++ b/utils/python-rpc/framework/wallet.py
@@ -297,7 +297,7 @@ class Wallet(object):
         }
         return self.rpc.send_json_rpc_request(query_key)
 
-    def restore_deterministic_wallet(self, seed = '', seed_offset = '', filename = '', restore_height = 0, password = '', language = '', autosave_current = True):
+    def restore_deterministic_wallet(self, seed = '', seed_offset = '', filename = '', restore_height = 0, password = '', language = '', autosave_current = True, enable_multisig_experimental = False):
         restore_deterministic_wallet = {
             'method': 'restore_deterministic_wallet',
             'params' : {
@@ -308,6 +308,7 @@ class Wallet(object):
                 'password': password,
                 'language': language,
                 'autosave_current': autosave_current,
+                'enable_multisig_experimental': enable_multisig_experimental
             },
             'jsonrpc': '2.0', 
             'id': '0'