Apply Bloom filters to DIP2 transactions extra payload (#2786)

* check matches for special transactions additional data

* additional method to check matches for CKeyID

* remove code duplication

* unit tests for bloom filters for DIP2 txes

* automatically update filters if special transaction matches

* unit tests for filter updates

* Error in comment

Co-Authored-By: gladcow <[email protected]>

* use switch instead of if-chain

* fix version check

* remove code duplication

* add negative tests in unit tests

src/bloom.cpp

@@ -5,6 +5,10 @@
 #include "bloom.h"
 
 #include "primitives/transaction.h"
+#include "evo/specialtx.h"
+#include "evo/providertx.h"
+#include "evo/cbtx.h"
+#include "llmq/quorums_commitment.h"
 #include "hash.h"
 #include "script/script.h"
 #include "script/standard.h"
@@ -113,6 +117,12 @@ bool CBloomFilter::contains(const uint256& hash) const
     return contains(data);
 }
 
+bool CBloomFilter::contains(const uint160& hash) const
+{
+    std::vector<unsigned char> data(hash.begin(), hash.end());
+    return contains(data);
+}
+
 void CBloomFilter::clear()
 {
     vData.assign(vData.size(),0);
@@ -131,6 +141,96 @@ bool CBloomFilter::IsWithinSizeConstraints() const
     return vData.size() <= MAX_BLOOM_FILTER_SIZE && nHashFuncs <= MAX_HASH_FUNCS;
 }
 
+// Match if the filter contains any arbitrary script data element in script
+bool CBloomFilter::CheckScript(const CScript &script) const
+{
+    CScript::const_iterator pc = script.begin();
+    std::vector<unsigned char> data;
+    while (pc < script.end()) {
+        opcodetype opcode;
+        if (!script.GetOp(pc, opcode, data))
+            break;
+        if (data.size() != 0 && contains(data))
+            return true;
+    }
+    return false;
+}
+
+// If the transaction is a special transaction that has a registration
+// transaction hash, test the registration transaction hash.
+// If the transaction is a special transaction with any public keys or any
+// public key hashes test them.
+// If the transaction is a special transaction with payout addresses test
+// the hash160 of those addresses.
+// Filter is updated only if it has BLOOM_UPDATE_ALL flag to be able to have
+// simple SPV wallets that doesn't work with DIP2 transactions (multicoin
+// wallets, etc.)
+bool CBloomFilter::CheckSpecialTransactionMatchesAndUpdate(const CTransaction &tx)
+{
+    if(tx.nVersion != 3 || tx.nType == TRANSACTION_NORMAL) {
+        return false; // it is not a special transaction
+    }
+    switch(tx.nType) {
+    case(TRANSACTION_PROVIDER_REGISTER): {
+        CProRegTx proTx;
+        if (GetTxPayload(tx, proTx)) {
+            if(contains(proTx.collateralOutpoint) ||
+                    contains(proTx.keyIDOwner) ||
+                    contains(proTx.keyIDVoting) ||
+                    CheckScript(proTx.scriptPayout)) {
+                if ((nFlags & BLOOM_UPDATE_MASK) == BLOOM_UPDATE_ALL)
+                    insert(tx.GetHash());
+                return true;
+            }
+        }
+        return false;
+    }
+    case(TRANSACTION_PROVIDER_UPDATE_SERVICE): {
+        CProUpServTx proTx;
+        if (GetTxPayload(tx, proTx)) {
+            if(contains(proTx.proTxHash)) {
+                return true;
+            }
+            if(CheckScript(proTx.scriptOperatorPayout)) {
+                if ((nFlags & BLOOM_UPDATE_MASK) == BLOOM_UPDATE_ALL)
+                    insert(proTx.proTxHash);
+                return true;
+            }
+        }
+        return false;
+    }
+    case(TRANSACTION_PROVIDER_UPDATE_REGISTRAR): {
+        CProUpRegTx proTx;
+        if (GetTxPayload(tx, proTx)) {
+            if(contains(proTx.proTxHash))
+                return true;
+            if(contains(proTx.keyIDVoting) ||
+                    CheckScript(proTx.scriptPayout)) {
+                if ((nFlags & BLOOM_UPDATE_MASK) == BLOOM_UPDATE_ALL)
+                    insert(proTx.proTxHash);
+                return true;
+            }
+        }
+        return false;
+    }
+    case(TRANSACTION_PROVIDER_UPDATE_REVOKE): {
+        CProUpRevTx proTx;
+        if (GetTxPayload(tx, proTx)) {
+            if(contains(proTx.proTxHash))
+                return true;
+        }
+        return false;
+    }
+    case(TRANSACTION_COINBASE):
+    case(TRANSACTION_QUORUM_COMMITMENT):
+        // No aditional checks for this transaction types
+        return false;
+    }
+
+    LogPrintf("Unknown special transaction type in Bloom filter check.");
+    return false;
+}
+
 bool CBloomFilter::IsRelevantAndUpdate(const CTransaction& tx)
 {
     bool fFound = false;
@@ -144,34 +244,27 @@ bool CBloomFilter::IsRelevantAndUpdate(const CTransaction& tx)
     if (contains(hash))
         fFound = true;
 
+    // Check additional matches for special transactions
+    fFound = fFound || CheckSpecialTransactionMatchesAndUpdate(tx);
+
     for (unsigned int i = 0; i < tx.vout.size(); i++)
     {
         const CTxOut& txout = tx.vout[i];
         // Match if the filter contains any arbitrary script data element in any scriptPubKey in tx
         // If this matches, also add the specific output that was matched.
         // This means clients don't have to update the filter themselves when a new relevant tx 
         // is discovered in order to find spending transactions, which avoids round-tripping and race conditions.
-        CScript::const_iterator pc = txout.scriptPubKey.begin();
-        std::vector<unsigned char> data;
-        while (pc < txout.scriptPubKey.end())
-        {
-            opcodetype opcode;
-            if (!txout.scriptPubKey.GetOp(pc, opcode, data))
-                break;
-            if (data.size() != 0 && contains(data))
+        if(CheckScript(txout.scriptPubKey)) {
+            fFound = true;
+            if ((nFlags & BLOOM_UPDATE_MASK) == BLOOM_UPDATE_ALL)
+                insert(COutPoint(hash, i));
+            else if ((nFlags & BLOOM_UPDATE_MASK) == BLOOM_UPDATE_P2PUBKEY_ONLY)
             {
-                fFound = true;
-                if ((nFlags & BLOOM_UPDATE_MASK) == BLOOM_UPDATE_ALL)
+                txnouttype type;
+                std::vector<std::vector<unsigned char> > vSolutions;
+                if (Solver(txout.scriptPubKey, type, vSolutions) &&
+                        (type == TX_PUBKEY || type == TX_MULTISIG))
                     insert(COutPoint(hash, i));
-                else if ((nFlags & BLOOM_UPDATE_MASK) == BLOOM_UPDATE_P2PUBKEY_ONLY)
-                {
-                    txnouttype type;
-                    std::vector<std::vector<unsigned char> > vSolutions;
-                    if (Solver(txout.scriptPubKey, type, vSolutions) &&
-                            (type == TX_PUBKEY || type == TX_MULTISIG))
-                        insert(COutPoint(hash, i));
-                }
-                break;
             }
         }
     }
@@ -186,16 +279,8 @@ bool CBloomFilter::IsRelevantAndUpdate(const CTransaction& tx)
             return true;
 
         // Match if the filter contains any arbitrary script data element in any scriptSig in tx
-        CScript::const_iterator pc = txin.scriptSig.begin();
-        std::vector<unsigned char> data;
-        while (pc < txin.scriptSig.end())
-        {
-            opcodetype opcode;
-            if (!txin.scriptSig.GetOp(pc, opcode, data))
-                break;
-            if (data.size() != 0 && contains(data))
-                return true;
-        }
+        if(CheckScript(txin.scriptSig))
+            return true;
     }
 
     return false;

src/bloom.h

@@ -10,8 +10,10 @@
 #include <vector>
 
 class COutPoint;
+class CScript;
 class CTransaction;
 class uint256;
+class uint160;
 
 //! 20,000 items with fp rate < 0.1% or 10,000 items and <0.0001%
 static const unsigned int MAX_BLOOM_FILTER_SIZE = 36000; // bytes
@@ -57,6 +59,10 @@ class CBloomFilter
     CBloomFilter(unsigned int nElements, double nFPRate, unsigned int nTweak);
     friend class CRollingBloomFilter;
 
+    // Check matches for arbitrary script data elements
+    bool CheckScript(const CScript& script) const;
+    // Check additional matches for special transactions
+    bool CheckSpecialTransactionMatchesAndUpdate(const CTransaction& tx);
 public:
     /**
      * Creates a new bloom filter which will provide the given fp rate when filled with the given number of elements
@@ -87,6 +93,7 @@ class CBloomFilter
     bool contains(const std::vector<unsigned char>& vKey) const;
     bool contains(const COutPoint& outpoint) const;
     bool contains(const uint256& hash) const;
+    bool contains(const uint160& hash) const;
 
     void clear();
     void reset(unsigned int nNewTweak);