Follow whole-script sizelimit.

Also add unit test for the op_return limits.

libs/server/policy/policy.cpp

@@ -70,7 +70,7 @@ bool IsStandard(const CScript &scriptPubKey, Script::TxnOutType &whichType, int
     } else if (whichType == Script::TX_NULL_DATA) {
         if (!fAcceptDatacarrier)
             return false;
-        dataUsed += scriptPubKey.size() - 3; // (-1 for OP_RETURN, -2 for the pushdata opcodes)
+        dataUsed += scriptPubKey.size();
     }
 
     return whichType != Script::TX_NONSTANDARD;

libs/utils/SettingsDefaults.h

@@ -34,7 +34,7 @@ constexpr uint32_t DefaultCheckLevel = 3;
 constexpr int32_t DefaultBlockAcceptSize = 128000000;
 
 constexpr bool DefaultAcceptDataCarrier = true;
-constexpr int MaxOpReturnRelay = 220; //! bytes
+constexpr int MaxOpReturnRelay = 223;
 constexpr bool DefaultRelayPriority = true;
 
 /** Default for setting that we download and accept blocks only (no transactions, no mempool) */

testing/bitcoin-protocol/transaction_tests.cpp

@@ -334,14 +334,34 @@ void TransactionTests::test_IsStandard()
     t.vout[0].scriptPubKey = CScript() << OP_RETURN
         << ParseHex("04678afdb0fe5548271967f1a67130b7105cd6a828e03909a67962e0ea1f61deb649f6bc3f4cef3804678afdb0fe5548271967f1a67130b7105cd6a828e03909a67962e0ea1f61deb649f6bc3f4cef38"
                     "0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000");
-    QCOMPARE(Settings::MaxOpReturnRelay + 3, t.vout[0].scriptPubKey.size());
+    QCOMPARE(Settings::MaxOpReturnRelay, t.vout[0].scriptPubKey.size());
     QVERIFY(IsStandardTx(t, reason));
 
+    // Multiple op-returns.
+    t.vout.push_back(t.vout.at(0));
+    t.vout[0].scriptPubKey = CScript() << OP_RETURN // 58 + 2 bytes
+        << ParseHex("04678afdb0fe55482719bc3f4cef3804678afdb0fe5548271967f1a67130b7105cd6a828e03909a67962e0ea1f61deb649f6bc3f4cef38123456");
+    t.vout[1].scriptPubKey = CScript() << OP_RETURN // 103 + 3 bytes
+        << ParseHex("04678afdb0fe55482719bc3f4cef3804678afdb0fe5548271967f1a67130b7105cd6a828e03909a67962e0ea1f61deb649f6bc3f4cef38"
+                    "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000");
+    QVERIFY(IsStandardTx(t, reason));
+
+    // limit is currently 223
+    t.vout.push_back(t.vout.at(0));
+    t.vout[2].scriptPubKey = CScript() << OP_RETURN // 57 + 2
+        << ParseHex("04678afdb0fe55482719bc3f4cef3804678afdb0fe5548271967f1a67130b7105cd6a828e03909a67962e0ea1f61deb649f6bc3f4cef38");
+    QVERIFY(IsStandardTx(t, reason)); // exactly within limit.
+    // one byte over limit.
+    t.vout[2].scriptPubKey = t.vout[1].scriptPubKey;
+    QCOMPARE(IsStandardTx(t, reason), false);
+    QCOMPARE(reason, "oversize-op-return");
+
+    t.vout.resize(1);
     // MAX_OP_RETURN_RELAY+1-byte TX_NULL_DATA (non-standard)
     t.vout[0].scriptPubKey = CScript() << OP_RETURN
         << ParseHex("04678afdb0fe5548271967f1a67130b7105cd6a828e03909a67962e0ea1f61deb649f6bc3f4cef3804678afdb0fe5548271967f1a67130b7105cd6a828e03909a67962e0ea1f61deb649f6bc3f4cef3800"
                     "0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000");
-    QCOMPARE(Settings::MaxOpReturnRelay + 4, t.vout[0].scriptPubKey.size());
+    QCOMPARE(Settings::MaxOpReturnRelay + 1, t.vout[0].scriptPubKey.size());
     QVERIFY(!IsStandardTx(t, reason));
 
     // Data payload can be encoded in any way...