4 files changed, 46 insertions, 1 deletions
diff --git a/src/cryptonote_core/blockchain.cpp b/src/cryptonote_core/blockchain.cpp
index 435a3fc0c..815f5b4f3 100644
--- a/src/cryptonote_core/blockchain.cpp
+++ b/src/cryptonote_core/blockchain.cpp
@@ -3097,6 +3097,8 @@ bool Blockchain::handle_block_to_main_chain(const block& bl, const crypto::hash&
   CRITICAL_REGION_LOCAL(m_blockchain_lock);
   TIME_MEASURE_START(t1);
 
+  static bool seen_future_version = false;
+
   m_db->block_txn_start(true);
   if(bl.prev_id != get_tail_id())
   {
@@ -3106,6 +3108,18 @@ leave:
     return false;
   }
 
+  // warn users if they're running an old version
+  if (!seen_future_version && bl.major_version > m_hardfork->get_ideal_version())
+  {
+    seen_future_version = true;
+    const el::Level level = el::Level::Warning;
+    MCLOG_RED(level, "global", "**********************************************************************");
+    MCLOG_RED(level, "global", "A block was seen on the network with a version higher than the last");
+    MCLOG_RED(level, "global", "known one. This may be an old version of the daemon, and a software");
+    MCLOG_RED(level, "global", "update may be required to sync further. Try running: update check");
+    MCLOG_RED(level, "global", "**********************************************************************");
+  }
+
   // this is a cheap test
   if (!m_hardfork->check(bl))
   {
diff --git a/src/cryptonote_core/cryptonote_core.cpp b/src/cryptonote_core/cryptonote_core.cpp
index 4cfa52441..da8ec68dd 100644
--- a/src/cryptonote_core/cryptonote_core.cpp
+++ b/src/cryptonote_core/cryptonote_core.cpp
@@ -660,6 +660,12 @@ namespace cryptonote
       return false;
     }
 
+    if (!check_tx_inputs_ring_members_diff(tx))
+    {
+      MERROR_VER("tx uses duplicate ring members");
+      return false;
+    }
+
     if (!check_tx_inputs_keyimages_domain(tx))
     {
       MERROR_VER("tx uses key image not in the valid domain");
@@ -752,6 +758,22 @@ namespace cryptonote
     return true;
   }
   //-----------------------------------------------------------------------------------------------
+  bool core::check_tx_inputs_ring_members_diff(const transaction& tx) const
+  {
+    const uint8_t version = m_blockchain_storage.get_current_hard_fork_version();
+    if (version >= 6)
+    {
+      for(const auto& in: tx.vin)
+      {
+        CHECKED_GET_SPECIFIC_VARIANT(in, const txin_to_key, tokey_in, false);
+        for (size_t n = 1; n < tokey_in.key_offsets.size(); ++n)
+          if (tokey_in.key_offsets[n] == 0)
+            return false;
+      }
+    }
+    return true;
+  }
+  //-----------------------------------------------------------------------------------------------
   bool core::check_tx_inputs_keyimages_domain(const transaction& tx) const
   {
     std::unordered_set<crypto::key_image> ki;
diff --git a/src/cryptonote_core/cryptonote_core.h b/src/cryptonote_core/cryptonote_core.h
index e5fbf7f91..4ced91e23 100644
--- a/src/cryptonote_core/cryptonote_core.h
+++ b/src/cryptonote_core/cryptonote_core.h
@@ -781,6 +781,15 @@ namespace cryptonote
      bool check_tx_inputs_keyimages_diff(const transaction& tx) const;
 
      /**
+      * @brief verify that each ring uses distinct members
+      *
+      * @param tx the transaction to check
+      *
+      * @return false if any ring uses duplicate members, true otherwise
+      */
+     bool check_tx_inputs_ring_members_diff(const transaction& tx) const;
+
+     /**
       * @brief verify that each input key image in a transaction is in
       * the valid domain
       *
diff --git a/src/cryptonote_core/cryptonote_tx_utils.cpp b/src/cryptonote_core/cryptonote_tx_utils.cpp
index 26d5fb767..abb4b31ec 100644
--- a/src/cryptonote_core/cryptonote_tx_utils.cpp
+++ b/src/cryptonote_core/cryptonote_tx_utils.cpp
@@ -265,7 +265,7 @@ namespace cryptonote
 
     // "Shuffle" outs
     std::vector<tx_destination_entry> shuffled_dsts(destinations);
-    std::sort(shuffled_dsts.begin(), shuffled_dsts.end(), [](const tx_destination_entry& de1, const tx_destination_entry& de2) { return de1.amount < de2.amount; } );
+    std::random_shuffle(shuffled_dsts.begin(), shuffled_dsts.end(), [](int i) { return crypto::rand<int>() % i; });
 
     uint64_t summary_outs_money = 0;
     //fill outputs