fixed segfault in bignum.h,

additional security limits,
refactoring
-- version 0.3.7

git-svn-id: https://bitcoin.svn.sourceforge.net/svnroot/bitcoin/trunk@121 1a98c847-1fd6-4fd8-948a-caf3550aa51b

1 files changed, 21 insertions, 11 deletions

diff --git a/script.cpp b/script.cpp
index 2b692caf42..a88f915900 100644
--- a/script.cpp
+++ b/script.cpp
@@ -42,20 +42,17 @@ void MakeSameSize(valtype& vch1, valtype& vch2)
 #define stacktop(i)  (stack.at(stack.size()+(i)))

 #define altstacktop(i)  (altstack.at(altstack.size()+(i)))

 

-bool EvalScript(const CScript& script, const CTransaction& txTo, unsigned int nIn, int nHashType,

-                vector<vector<unsigned char> >* pvStackRet)

+bool EvalScript(vector<vector<unsigned char> >& stack, const CScript& script, const CTransaction& txTo, unsigned int nIn, int nHashType)

 {

     CAutoBN_CTX pctx;

     CScript::const_iterator pc = script.begin();

     CScript::const_iterator pend = script.end();

     CScript::const_iterator pbegincodehash = script.begin();

     vector<bool> vfExec;

-    vector<valtype> stack;

     vector<valtype> altstack;

-    if (pvStackRet)

-        pvStackRet->clear();

-    if (script.size() > 20000)

+    if (script.size() > 10000)

         return false;

+    int nOpCount = 0;

 

 

     try

@@ -73,6 +70,8 @@ bool EvalScript(const CScript& script, const CTransaction& txTo, unsigned int nI
                 return false;

             if (vchPushValue.size() > 5000)

                 return false;

+            if (opcode > OP_16 && nOpCount++ > 200)

+                return false;

 

             if (fExec && opcode <= OP_PUSHDATA4)

                 stack.push_back(vchPushValue);

@@ -828,9 +827,7 @@ bool EvalScript(const CScript& script, const CTransaction& txTo, unsigned int nI
     if (!vfExec.empty())

         return false;

 

-    if (pvStackRet)

-        *pvStackRet = stack;

-    return (stack.empty() ? false : CastToBool(stack.back()));

+    return true;

 }

 

 #undef top

@@ -1114,6 +1111,19 @@ bool ExtractHash160(const CScript& scriptPubKey, uint160& hash160Ret)
 }

 

 

+bool VerifyScript(const CScript& scriptSig, const CScript& scriptPubKey, const CTransaction& txTo, unsigned int nIn, int nHashType)

+{

+    vector<vector<unsigned char> > stack;

+    if (!EvalScript(stack, scriptSig, txTo, nIn, nHashType))

+        return false;

+    if (!EvalScript(stack, scriptPubKey, txTo, nIn, nHashType))

+        return false;

+    if (stack.empty())

+        return false;

+    return CastToBool(stack.back());

+}

+

+

 bool SignSignature(const CTransaction& txFrom, CTransaction& txTo, unsigned int nIn, int nHashType, CScript scriptPrereq)

 {

     assert(nIn < txTo.vin.size());

@@ -1132,7 +1142,7 @@ bool SignSignature(const CTransaction& txFrom, CTransaction& txTo, unsigned int
 

     // Test solution

     if (scriptPrereq.empty())

-        if (!EvalScript(txin.scriptSig + CScript(OP_CODESEPARATOR) + txout.scriptPubKey, txTo, nIn))

+        if (!VerifyScript(txin.scriptSig, txout.scriptPubKey, txTo, nIn, 0))

             return false;

 

     return true;

@@ -1150,7 +1160,7 @@ bool VerifySignature(const CTransaction& txFrom, const CTransaction& txTo, unsig
     if (txin.prevout.hash != txFrom.GetHash())

         return false;

 

-    if (!EvalScript(txin.scriptSig + CScript(OP_CODESEPARATOR) + txout.scriptPubKey, txTo, nIn, nHashType))

+    if (!VerifyScript(txin.scriptSig, txout.scriptPubKey, txTo, nIn, nHashType))

         return false;

 

     // Anytime a signature is successfully verified, it's proof the outpoint is spent,