* make interface for getting tx safer in Eval

* restrict lengths in cryptoconditions to avoid ridiculous situations

src/cc/disputepayout.cpp

@@ -33,29 +33,27 @@ bool Eval::DisputePayout(AppVM &vm, const CC *cond, const CTransaction &disputeT
 
     // load dispute header
     DisputeHeader disputeHeader;
-    std::vector<unsigned char> headerData(cond->paramsBin,
-                                          cond->paramsBin+cond->paramsBinLength);
+    std::vector<unsigned char> headerData(
+            cond->paramsBin, cond->paramsBin+cond->paramsBinLength);
     if (!CheckDeserialize(headerData, disputeHeader))
         return Invalid("invalid-dispute-header");
 
     // ensure that enough time has passed
-    CTransaction sessionTx;
-    uint256 sessionBlockHash;
-    CBlockIndex sessionBlock;
-    
-    if (!GetTx(disputeTx.vin[0].prevout.hash, sessionTx, sessionBlockHash, false))
-        return Error("couldnt-get-parent");
-    // TODO: This may not be an error, if both txs are to go into the same block...
-    // Probably change it to Invalid
-    if (!GetBlock(sessionBlockHash, sessionBlock))
-        return Error("couldnt-get-block");
+    {
+        CTransaction sessionTx;
+        CBlockIndex sessionBlock;
+        
+        // if unconformed its too soon
+        if (!GetTxConfirmed(disputeTx.vin[0].prevout.hash, sessionTx, sessionBlock))
+            return Error("couldnt-get-parent");
 
-    if (GetCurrentHeight() < sessionBlock.nHeight + disputeHeader.waitBlocks)
-        return Invalid("dispute-too-soon");  // Not yet
+        if (GetCurrentHeight() < sessionBlock.nHeight + disputeHeader.waitBlocks)
+            return Invalid("dispute-too-soon");  // Not yet
+    }
 
     // get spends
     std::vector<CTransaction> spends;
-    if (!GetSpends(disputeTx.vin[0].prevout.hash, spends))
+    if (!GetSpendsConfirmed(disputeTx.vin[0].prevout.hash, spends))
         return Error("couldnt-get-spends");
 
     // verify result from VM

src/cc/eval.cpp

@@ -57,19 +57,31 @@ bool Eval::Dispatch(const CC *cond, const CTransaction &txTo, unsigned int nIn)
 }
 
 
-bool Eval::GetSpends(uint256 hash, std::vector<CTransaction> &spends) const
+bool Eval::GetSpendsConfirmed(uint256 hash, std::vector<CTransaction> &spends) const
 {
     // NOT IMPLEMENTED
     return false;
 }
 
 
-bool Eval::GetTx(const uint256 &hash, CTransaction &txOut, uint256 &hashBlock, bool fAllowSlow) const
+bool Eval::GetTxUnconfirmed(const uint256 &hash, CTransaction &txOut, uint256 &hashBlock) const
 {
+    bool fAllowSlow = false; // Don't allow slow
     return GetTransaction(hash, txOut, hashBlock, fAllowSlow);
 }
 
 
+bool Eval::GetTxConfirmed(const uint256 &hash, CTransaction &txOut, CBlockIndex &block) const
+{
+    uint256 hashBlock;
+    if (!GetTxUnconfirmed(hash, txOut, hashBlock))
+        return false;
+    if (hashBlock.IsNull() || !GetBlock(hashBlock, block))
+        return false;
+    return true;
+}
+
+
 unsigned int Eval::GetCurrentHeight() const
 {
     return chainActive.Height();
@@ -83,6 +95,7 @@ bool Eval::GetBlock(uint256 hash, CBlockIndex& blockIdx) const
         blockIdx = *r->second;
         return true;
     }
+    fprintf(stderr, "CC Eval Error: Can't get block from index\n");
     return false;
 }
 
@@ -109,7 +122,7 @@ bool Eval::CheckNotaryInputs(const CTransaction &tx, uint32_t height, uint32_t t
         // Get notary pubkey
         CTransaction tx;
         uint256 hashBlock;
-        if (!GetTx(txIn.prevout.hash, tx, hashBlock, false)) return false;
+        if (!GetTxUnconfirmed(txIn.prevout.hash, tx, hashBlock)) return false;
         if (tx.vout.size() < txIn.prevout.n) return false;
         CScript spk = tx.vout[txIn.prevout.n].scriptPubKey;
         if (spk.size() != 35) return false;
@@ -173,10 +186,8 @@ bool NotarisationData::Parse(const CScript scriptPK)
 bool Eval::GetNotarisationData(const uint256 notaryHash, NotarisationData &data) const
 {
     CTransaction notarisationTx;
-    uint256 notarisationBlock;
-    if (!GetTx(notaryHash, notarisationTx, notarisationBlock, true)) return false;
     CBlockIndex block;
-    if (!GetBlock(notarisationBlock, block)) return false;
+    if (!GetTxConfirmed(notaryHash, notarisationTx, block)) return false;
     if (!CheckNotaryInputs(notarisationTx, block.nHeight, block.nTime)) return false;
     if (notarisationTx.vout.size() < 2) return false;
     if (!data.Parse(notarisationTx.vout[1].scriptPubKey)) return false;

src/cc/eval.h

@@ -41,9 +41,10 @@ public:
     /*
      * IO functions
      */
-    virtual bool GetTx(const uint256 &hash, CTransaction &txOut, uint256 &hashBlock, bool fAllowSlow) const;
+    virtual bool GetTxUnconfirmed(const uint256 &hash, CTransaction &txOut, uint256 &hashBlock) const;
+    virtual bool GetTxConfirmed(const uint256 &hash, CTransaction &txOut, CBlockIndex &block) const;
     virtual unsigned int GetCurrentHeight() const;
-    virtual bool GetSpends(uint256 hash, std::vector<CTransaction> &spends) const;
+    virtual bool GetSpendsConfirmed(uint256 hash, std::vector<CTransaction> &spends) const;
     virtual bool GetBlock(uint256 hash, CBlockIndex& blockIdx) const;
     virtual int32_t GetNotaries(uint8_t pubkeys[64][33], int32_t height, uint32_t timestamp) const;
     virtual bool GetNotarisationData(uint256 notarisationHash, NotarisationData &data) const;