Add a size limit for tx_extra in tx pool [release-v0.18]

src/cryptonote_basic/verification_context.h

@@ -53,6 +53,7 @@ namespace cryptonote
     bool m_overspend;
     bool m_fee_too_low;
     bool m_too_few_outputs;
+    bool m_tx_extra_too_big;
   };
 
   struct block_verification_context

src/cryptonote_config.h

@@ -206,6 +206,11 @@
 
 #define DNS_BLOCKLIST_LIFETIME (86400 * 8)
 
+//The limit is enough for the mandatory transaction content with 16 outputs (547 bytes),
+//a custom tag (1 byte) and up to 32 bytes of custom data for each recipient.
+// (1+32) + (1+1+16*32) + (1+16*32) = 1060
+#define MAX_TX_EXTRA_SIZE                       1060
+
 // New constants are intended to go here
 namespace config
 {

src/cryptonote_core/cryptonote_tx_utils.cpp

@@ -437,6 +437,8 @@ namespace cryptonote
     if (!sort_tx_extra(tx.extra, tx.extra))
       return false;
 
+    CHECK_AND_ASSERT_MES(tx.extra.size() <= MAX_TX_EXTRA_SIZE, false, "TX extra size (" << tx.extra.size() << ") is greater than max allowed (" << MAX_TX_EXTRA_SIZE << ")");
+
     //check money
     if(summary_outs_money > summary_inputs_money )
     {

src/cryptonote_core/tx_pool.cpp

@@ -219,6 +219,15 @@ namespace cryptonote
       return false;
     }
 
+    size_t tx_extra_size = tx.extra.size();
+    if (!kept_by_block && tx_extra_size > MAX_TX_EXTRA_SIZE)
+    {
+      LOG_PRINT_L1("transaction tx-extra is too big: " << tx_extra_size << " bytes, the limit is: " << MAX_TX_EXTRA_SIZE);
+      tvc.m_verifivation_failed = true;
+      tvc.m_tx_extra_too_big = true;
+      return false;
+    }
+
     // if the transaction came from a block popped from the chain,
     // don't check if we have its key images as spent.
     // TODO: Investigate why not?

src/rpc/core_rpc_server.cpp

@@ -1275,6 +1275,8 @@ namespace cryptonote
           add_reason(reason, "fee too low");
         if ((res.too_few_outputs = tvc.m_too_few_outputs))
           add_reason(reason, "too few outputs");
+        if ((res.tx_extra_too_big = tvc.m_tx_extra_too_big))
+          add_reason(reason, "tx-extra too big");
         const std::string punctuation = reason.empty() ? "" : ": ";
         if (tvc.m_verifivation_failed)
         {

src/rpc/core_rpc_server_commands_defs.h

@@ -88,7 +88,7 @@ namespace cryptonote
 // advance which version they will stop working with
 // Don't go over 32767 for any of these
 #define CORE_RPC_VERSION_MAJOR 3
-#define CORE_RPC_VERSION_MINOR 11
+#define CORE_RPC_VERSION_MINOR 12
 #define MAKE_CORE_RPC_VERSION(major,minor) (((major)<<16)|(minor))
 #define CORE_RPC_VERSION MAKE_CORE_RPC_VERSION(CORE_RPC_VERSION_MAJOR, CORE_RPC_VERSION_MINOR)
 
@@ -592,6 +592,7 @@ namespace cryptonote
       bool fee_too_low;
       bool too_few_outputs;
       bool sanity_check_failed;
+      bool tx_extra_too_big;
 
       BEGIN_KV_SERIALIZE_MAP()
         KV_SERIALIZE_PARENT(rpc_access_response_base)
@@ -606,6 +607,7 @@ namespace cryptonote
         KV_SERIALIZE(fee_too_low)
         KV_SERIALIZE(too_few_outputs)
         KV_SERIALIZE(sanity_check_failed)
+        KV_SERIALIZE(tx_extra_too_big)
       END_KV_SERIALIZE_MAP()
     };
     typedef epee::misc_utils::struct_init<response_t> response;