[rpc] sendrawtransaction no longer bypasses minRelayTxFee

The prioritisetransaction API can always be used if a transaction needs to be submitted that bypasses minRelayTxFee.

(cherry picked from commit bitcoin/bitcoin@ad727f4eaf)

Signed-off-by: Daira Emma Hopwood <daira@jacaranda.org>

qa/rpc-tests/mempool_packages.py

@@ -25,7 +25,6 @@ class MempoolPackagesTest(BitcoinTestFramework):
     def setup_network(self):
         base_args = [
             "-maxorphantx=1000",
-            "-relaypriority=0",
             "-debug",
             "-allowdeprecated=getnewaddress",
         ]

qa/rpc-tests/prioritisetransaction.py

@@ -29,7 +29,6 @@ class PrioritiseTransactionTest (BitcoinTestFramework):
         args = [
             "-blockmaxsize=11000",
             "-maxorphantx=1000",
-            "-relaypriority=true",
             "-printpriority=1",
             "-limitancestorcount=900",
             "-allowdeprecated=getnewaddress",

qa/rpc-tests/smartfees.py

@@ -156,7 +156,7 @@ class EstimateFeeTest(BitcoinTestFramework):
         self.nodes = []
         # Use node0 to mine blocks for input splitting
         self.nodes.append(start_node(0, self.options.tmpdir, ["-maxorphantx=1000",
-                                                              "-relaypriority=0", "-whitelist=127.0.0.1"]))
+                                                              "-whitelist=127.0.0.1"]))
 
         print("This test is time consuming, please be patient")
         print("Splitting inputs to small size so we can generate low priority tx's")
@@ -188,17 +188,16 @@ class EstimateFeeTest(BitcoinTestFramework):
 
         # Now we can connect the other nodes, didn't want to connect them earlier
         # so the estimates would not be affected by the splitting transactions
-        # Node1 mines small blocks but that are bigger than the expected transaction rate,
+        # Node1 mines small blocks but that are bigger than the expected transaction rate.
-        # and allows free transactions.
         # NOTE: the CreateNewBlock code starts counting block size at 1,000 bytes,
         # (17k is room enough for 110 or so transactions)
         self.nodes.append(start_node(1, self.options.tmpdir,
-                                     ["-blockmaxsize=18000", "-maxorphantx=1000", "-relaypriority=0", "-debug=estimatefee"]))
+                                     ["-blockmaxsize=18000", "-maxorphantx=1000", "-debug=estimatefee"]))
         connect_nodes(self.nodes[1], 0)
 
         # Node2 is a stingy miner, that
         # produces too small blocks (room for only 70 or so transactions)
-        node2args = ["-blockmaxsize=12000", "-maxorphantx=1000", "-relaypriority=0"]
+        node2args = ["-blockmaxsize=12000", "-maxorphantx=1000"]
 
         self.nodes.append(start_node(2, self.options.tmpdir, node2args))
         connect_nodes(self.nodes[0], 2)

src/init.cpp

@@ -479,8 +479,6 @@ std::string HelpMessage(HelpMessageMode mode)
     {
         strUsage += HelpMessageOpt("-clockoffset=<n>", "Applies offset of <n> seconds to the actual time. Incompatible with -mocktime (default: 0)");
         strUsage += HelpMessageOpt("-mocktime=<n>", "Replace actual time with <n> seconds since epoch. Incompatible with -clockoffset (default: 0)");
-        strUsage += HelpMessageOpt("-limitfreerelay=<n>", strprintf("Continuously rate-limit free transactions to <n>*1000 bytes per minute (default: %u)", DEFAULT_LIMITFREERELAY));
-        strUsage += HelpMessageOpt("-relaypriority", strprintf("Require high priority for relaying free or low-fee transactions (default: %u)", DEFAULT_RELAYPRIORITY));
         strUsage += HelpMessageOpt("-maxsigcachesize=<n>", strprintf("Limit total size of signature and bundle caches to <n> MiB (default: %u)", DEFAULT_MAX_SIG_CACHE_SIZE));
         strUsage += HelpMessageOpt("-maxtipage=<n>", strprintf("Maximum tip age in seconds to consider node in initial block download (default: %u)", DEFAULT_MAX_TIP_AGE));
     }
@@ -1227,7 +1225,7 @@ bool AppInit2(boost::thread_group& threadGroup, CScheduler& scheduler)
     if (nConnectTimeout <= 0)
         nConnectTimeout = DEFAULT_CONNECT_TIMEOUT;
 
-    // Fee-per-kilobyte amount considered the same as "free"
+    // Fee-per-kilobyte amount required for mempool acceptance and relay
     // If you are mining, be careful setting this:
     // if you set it to zero then
     // a transaction spammer can cheaply fill blocks using

src/main.cpp

@@ -1938,32 +1938,11 @@ bool AcceptToMemoryPool(
         CTxMemPoolEntry entry(tx, nFees, GetTime(), dPriority, chainActive.Height(), pool.HasNoInputsOf(tx), fSpendsCoinbase, nSigOps, consensusBranchId);
         unsigned int nSize = entry.GetTxSize();
 
-        // Require that free transactions have sufficient priority to be mined in the next block.
+        // No transactions are allowed with modified fee below the minimum relay fee,
-        if (GetBoolArg("-relaypriority", DEFAULT_RELAYPRIORITY) && nModifiedFees < ::minRelayTxFee.GetFeeForRelay(nSize) && !AllowFree(view.GetPriority(tx, chainActive.Height() + 1))) {
+        // except from disconnected blocks. The minimum relay fee will never be more
-            return state.DoS(0, false, REJECT_INSUFFICIENTFEE, "insufficient priority");
+        // than DEFAULT_FEE zatoshis.
-        }
+        if (fLimitFree && nModifiedFees < ::minRelayTxFee.GetFeeForRelay(nSize)) {
-
+            return state.DoS(0, false, REJECT_INSUFFICIENTFEE, "min relay fee not met");
-        // Continuously rate-limit free (really, very-low-fee) transactions
-        // This mitigates 'penny-flooding' -- sending thousands of free transactions just to
-        // be annoying or make others' transactions take longer to confirm.
-        if (fLimitFree && nModifiedFees < ::minRelayTxFee.GetFeeForRelay(nSize))
-        {
-            static CCriticalSection csFreeLimiter;
-            static double dFreeCount;
-            static int64_t nLastTime;
-            int64_t nNow = GetTime();
-
-            LOCK(csFreeLimiter);
-
-            // Use an exponentially decaying ~10-minute window:
-            dFreeCount *= pow(1.0 - 1.0/600.0, (double)(nNow - nLastTime));
-            nLastTime = nNow;
-            // -limitfreerelay unit is thousand-bytes-per-minute
-            // At default rate it would take over a month to fill 1GB
-            if (dFreeCount >= GetArg("-limitfreerelay", DEFAULT_LIMITFREERELAY) * 10 * 1000)
-                return state.DoS(0, false, REJECT_INSUFFICIENTFEE, "rate limited free transaction");
-            LogPrint("mempool", "Rate limit dFreeCount: %g => %g\n", dFreeCount, dFreeCount+nSize);
-            dFreeCount += nSize;
         }
 
         if (fRejectAbsurdFee && nFees > maxTxFee) {
@@ -7175,7 +7154,7 @@ bool static ProcessMessage(const CChainParams& chainparams, CNode* pfrom, string
                             LogPrint("mempool", "   invalid orphan tx %s\n", orphanHash.ToString());
                         }
                         // Has inputs but not accepted to mempool
-                        // Probably non-standard or insufficient fee/priority
+                        // Probably non-standard or insufficient fee
                         LogPrint("mempool", "   removed orphan tx %s\n", orphanHash.ToString());
                         vEraseQueue.push_back(orphanHash);
                         // Add the wtxid of this transaction to our reject filter.

src/main.h

@@ -135,8 +135,6 @@ static const unsigned int INVENTORY_BROADCAST_INTERVAL = 5;
  *  Limits the impact of low-fee transaction floods. */
 static const unsigned int INVENTORY_BROADCAST_MAX = 7 * INVENTORY_BROADCAST_INTERVAL;
 
-static const unsigned int DEFAULT_LIMITFREERELAY = 15;
-static const bool DEFAULT_RELAYPRIORITY = false;
 static const int64_t DEFAULT_MAX_TIP_AGE = 24 * 60 * 60;
 
 /** Default for -permitbaremultisig */

src/rpc/misc.cpp

@@ -68,7 +68,7 @@ UniValue getinfo(const UniValue& params, bool fHelp)
             "  \"keypoolsize\": xxxx,        (numeric, optional) how many new keys are pre-generated\n"
             "  \"unlocked_until\": ttt,      (numeric, optional) the timestamp in seconds since epoch (midnight Jan 1 1970 GMT) that the wallet is unlocked for transfers, or 0 if the wallet is locked, if wallet functionality is available and the wallet is encrypted\n"
             "  \"paytxfee\": x.xxxx,         (numeric) the transaction fee set in " + CURRENCY_UNIT + "/kB\n"
-            "  \"relayfee\": x.xxxx,         (numeric) minimum relay fee for non-free transactions in " + CURRENCY_UNIT + "/kB\n"
+            "  \"relayfee\": x.xxxx,         (numeric) minimum relay fee for transactions in " + CURRENCY_UNIT + "/kB\n"
             "  \"errors\": \"...\"           (string) message describing the latest or highest-priority error\n"
             "  \"errorstimestamp\": \"...\"  (string) timestamp associated with the latest or highest-priority error\n"
             "}\n"

src/rpc/net.cpp

@@ -516,7 +516,7 @@ UniValue getnetworkinfo(const UniValue& params, bool fHelp)
             "  }\n"
             "  ,...\n"
             "  ],\n"
-            "  \"relayfee\": x.xxxxxxxx,                (numeric) minimum relay fee for non-free transactions in " + CURRENCY_UNIT + "/kB\n"
+            "  \"relayfee\": x.xxxxxxxx,                (numeric) minimum relay fee for transactions in " + CURRENCY_UNIT + "/kB\n"
             "  \"localaddresses\": [                    (array) list of local addresses\n"
             "  {\n"
             "    \"address\": \"xxxx\",                 (string) network address\n"

src/rpc/rawtransaction.cpp

@@ -1285,7 +1285,7 @@ UniValue sendrawtransaction(const UniValue& params, bool fHelp)
         // push to local node and sync with wallets
         CValidationState state;
         bool fMissingInputs;
-        if (!AcceptToMemoryPool(chainparams, mempool, state, tx, false, &fMissingInputs, !fOverrideFees)) {
+        if (!AcceptToMemoryPool(chainparams, mempool, state, tx, true, &fMissingInputs, !fOverrideFees)) {
             if (state.IsInvalid()) {
                 throw JSONRPCError(RPC_TRANSACTION_REJECTED, strprintf("%i: %s", state.GetRejectCode(), state.GetRejectReason()));
             } else {

src/txmempool.h

@@ -28,22 +28,6 @@
 
 class CAutoFile;
 
-inline double AllowFreeThreshold()
-{
-    // 144 is the number of Bitcoin blocks per day. This has not been updated for Zcash,
-    // as it would make it harder to get shielded transactions into blocks by lowering the
-    // threshold at which we switch from priority-based selection of transactions into
-    // blocks to fee-based selection.
-    return COIN * 144 / 250;
-}
-
-inline bool AllowFree(double dPriority)
-{
-    // Large (in bytes) low-priority (new, small-coin) transactions
-    // need a fee.
-    return dPriority > AllowFreeThreshold();
-}
-
 /** Version from which we write `fee_estimates.dat` without priority information: 5.5.0-beta1 or later */
 static const int FEE_ESTIMATES_WITHOUT_PRIORITY_VERSION = 5050000;