[policy] restrict all v3 transactions to 10kvB

2 files changed, 17 insertions, 2 deletions

diff --git a/src/policy/v3_policy.cpp b/src/policy/v3_policy.cpp
index 3c3942d707..d44832fceb 100644
--- a/src/policy/v3_policy.cpp
+++ b/src/policy/v3_policy.cpp
@@ -67,6 +67,12 @@ std::optional<std::string> PackageV3Checks(const CTransactionRef& ptx, int64_t v
 
     // Now we have all ancestors, so we can start checking v3 rules.
     if (ptx->nVersion == 3) {
+        // SingleV3Checks should have checked this already.
+        if (!Assume(vsize <= V3_MAX_VSIZE)) {
+            return strprintf("v3 tx %s (wtxid=%s) is too big: %u > %u virtual bytes",
+                             ptx->GetHash().ToString(), ptx->GetWitnessHash().ToString(), vsize, V3_MAX_VSIZE);
+        }
+
         if (mempool_ancestors.size() + in_package_parents.size() + 1 > V3_ANCESTOR_LIMIT) {
             return strprintf("tx %s (wtxid=%s) would have too many ancestors",
                              ptx->GetHash().ToString(), ptx->GetWitnessHash().ToString());
@@ -186,6 +192,12 @@ std::optional<std::pair<std::string, CTransactionRef>> SingleV3Checks(const CTra
     // The rest of the rules only apply to transactions with nVersion=3.
     if (ptx->nVersion != 3) return std::nullopt;
 
+    if (vsize > V3_MAX_VSIZE) {
+        return std::make_pair(strprintf("v3 tx %s (wtxid=%s) is too big: %u > %u virtual bytes",
+                         ptx->GetHash().ToString(), ptx->GetWitnessHash().ToString(), vsize, V3_MAX_VSIZE),
+            nullptr);
+    }
+
     // Check that V3_ANCESTOR_LIMIT would not be violated.
     if (mempool_ancestors.size() + 1 > V3_ANCESTOR_LIMIT) {
         return std::make_pair(strprintf("tx %s (wtxid=%s) would have too many ancestors",
diff --git a/src/policy/v3_policy.h b/src/policy/v3_policy.h
index 2e56f8822b..25aff37a1b 100644
--- a/src/policy/v3_policy.h
+++ b/src/policy/v3_policy.h
@@ -24,11 +24,13 @@ static constexpr unsigned int V3_DESCENDANT_LIMIT{2};
 /** Maximum number of transactions including a V3 tx and all its mempool ancestors. */
 static constexpr unsigned int V3_ANCESTOR_LIMIT{2};
 
+/** Maximum sigop-adjusted virtual size of all v3 transactions. */
+static constexpr int64_t V3_MAX_VSIZE{10000};
 /** Maximum sigop-adjusted virtual size of a tx which spends from an unconfirmed v3 transaction. */
 static constexpr int64_t V3_CHILD_MAX_VSIZE{1000};
 // These limits are within the default ancestor/descendant limits.
-static_assert(V3_CHILD_MAX_VSIZE + MAX_STANDARD_TX_WEIGHT / WITNESS_SCALE_FACTOR <= DEFAULT_ANCESTOR_SIZE_LIMIT_KVB * 1000);
-static_assert(V3_CHILD_MAX_VSIZE + MAX_STANDARD_TX_WEIGHT / WITNESS_SCALE_FACTOR <= DEFAULT_DESCENDANT_SIZE_LIMIT_KVB * 1000);
+static_assert(V3_MAX_VSIZE + V3_CHILD_MAX_VSIZE <= DEFAULT_ANCESTOR_SIZE_LIMIT_KVB * 1000);
+static_assert(V3_MAX_VSIZE + V3_CHILD_MAX_VSIZE <= DEFAULT_DESCENDANT_SIZE_LIMIT_KVB * 1000);
 
 /** Must be called for every transaction, even if not v3. Not strictly necessary for transactions
  * accepted through AcceptMultipleTransactions.
@@ -40,6 +42,7 @@ static_assert(V3_CHILD_MAX_VSIZE + MAX_STANDARD_TX_WEIGHT / WITNESS_SCALE_FACTOR
  * 4. A v3's descendant set, including itself, must be within V3_DESCENDANT_LIMIT.
  * 5. If a v3 tx has any unconfirmed ancestors, the tx's sigop-adjusted vsize must be within
  * V3_CHILD_MAX_VSIZE.
+ * 6. A v3 tx must be within V3_MAX_VSIZE.
  *
  *
  * @param[in]   mempool_ancestors       The in-mempool ancestors of ptx.