From b2516d2435f6916974ecd19241514b421a823a01 Mon Sep 17 00:00:00 2001
From: Sunny King <sunnyking9999@gmail.com>
Date: Thu, 5 Jul 2012 18:59:06 +0100
Subject: [PATCH] PPCoin: Sign block when communicating with miners via RPC 'getwork'

---
 src/bitcoinrpc.cpp |    6 ++++--
 src/main.cpp       |   52 +++++++++++++++++++++++++++++++---------------------
 src/main.h         |    2 +-
 3 files changed, 36 insertions(+), 24 deletions(-)

diff --git a/src/bitcoinrpc.cpp b/src/bitcoinrpc.cpp
index bd988e9..e68f1fe 100644
--- a/src/bitcoinrpc.cpp
+++ b/src/bitcoinrpc.cpp
@@ -1657,14 +1657,14 @@ Value getwork(const Array& params, bool fHelp)
             nStart = GetTime();
 
             // Create new block
-            pblock = CreateNewBlock(pwalletMain);
+            pblock = CreateNewBlock(pwalletMain, true);
             if (!pblock)
                 throw JSONRPCError(-7, "Out of memory");
             vNewBlock.push_back(pblock);
         }
 
         // Update nTime
-        pblock->nTime = max(pindexPrev->GetMedianTimePast()+1, GetAdjustedTime());
+        pblock->nTime = max(pblock->GetBlockTime(), GetAdjustedTime());
         pblock->nNonce = 0;
 
         // Update nExtraNonce
@@ -1710,6 +1710,8 @@ Value getwork(const Array& params, bool fHelp)
         pblock->nNonce = pdata->nNonce;
         pblock->vtx[0].vin[0].scriptSig = mapNewBlock[pdata->hashMerkleRoot].second;
         pblock->hashMerkleRoot = pblock->BuildMerkleTree();
+        if (!pblock->SignBlock(*pwalletMain))
+            throw JSONRPCError(-100, "Unable to sign block");
 
         return CheckWork(pblock, *pwalletMain, reservekey);
     }
diff --git a/src/main.cpp b/src/main.cpp
index ab9026b..263a9e9 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -3052,7 +3052,7 @@ public:
 };
 
 
-CBlock* CreateNewBlock(CWallet* pwallet)
+CBlock* CreateNewBlock(CWallet* pwallet, bool fProofOfWorkOnly)
 {
     CReserveKey reservekey(pwallet);
 
@@ -3074,24 +3074,28 @@ CBlock* CreateNewBlock(CWallet* pwallet)
     // ppcoin: if coinstake available add coinstake tx
     static unsigned int nLastCoinStakeCheckTime = GetAdjustedTime() - nMaxClockDrift + 60;  // only initialized at startup
     CBlockIndex* pindexPrev = pindexBest;
-    while (nLastCoinStakeCheckTime < GetAdjustedTime())
+
+    if (!fProofOfWorkOnly)
     {
-        pindexPrev = pindexBest;  // get best block again to avoid getting stale
-        pblock->nBits = GetNextTargetRequired(pindexPrev, true);
-        static CCriticalSection cs;
-        CTransaction txCoinStake;
-        CRITICAL_BLOCK(cs)
-        {
-            // mining may have been suspended for a while so 
-            // need to take max to satisfy the timestamp protocol
-            nLastCoinStakeCheckTime = max(++nLastCoinStakeCheckTime, (unsigned int) (GetAdjustedTime() - nMaxClockDrift + 60));
-            txCoinStake.nTime = nLastCoinStakeCheckTime;
-        }
-        if (pwallet->CreateCoinStake(pblock->nBits, txCoinStake))
+        while (nLastCoinStakeCheckTime < GetAdjustedTime())
         {
-            pblock->vtx.push_back(txCoinStake);
-            pblock->vtx[0].vout[0].SetEmpty();
-            break;
+            pindexPrev = pindexBest;  // get best block again to avoid getting stale
+            pblock->nBits = GetNextTargetRequired(pindexPrev, true);
+            static CCriticalSection cs;
+            CTransaction txCoinStake;
+            CRITICAL_BLOCK(cs)
+            {
+                // mining may have been suspended for a while so 
+                // need to take max to satisfy the timestamp protocol
+                nLastCoinStakeCheckTime = max(++nLastCoinStakeCheckTime, (unsigned int) (GetAdjustedTime() - nMaxClockDrift + 60));
+                txCoinStake.nTime = nLastCoinStakeCheckTime;
+            }
+            if (pwallet->CreateCoinStake(pblock->nBits, txCoinStake))
+            {
+                pblock->vtx.push_back(txCoinStake);
+                pblock->vtx[0].vout[0].SetEmpty();
+                break;
+            }
         }
     }
 
@@ -3370,8 +3374,11 @@ void static BitcoinMiner(CWallet *pwallet)
         // ppcoin: if proof-of-stake block found then process block
         if (pblock->IsProofOfStake())
         {
-            // should be able to sign block - assert here for now
-            assert(pblock->SignBlock(*pwalletMain));
+            if (!pblock->SignBlock(*pwalletMain))
+            {
+                error("BitcoinMiner: Unable to sign new proof-of-stake block");
+                return;
+            }
             printf("BitcoinMiner : proof-of-stake block found %s\n", pblock->GetHash().ToString().c_str()); 
             SetThreadPriority(THREAD_PRIORITY_NORMAL);
             CheckWork(pblock.get(), *pwalletMain, reservekey);
@@ -3422,8 +3429,11 @@ void static BitcoinMiner(CWallet *pwallet)
                     // Found a solution
                     pblock->nNonce = ByteReverse(nNonceFound);
                     assert(hash == pblock->GetHash());
-                    // should be able to sign block - assert here for now
-                    assert(pblock->SignBlock(*pwalletMain));
+                    if (!pblock->SignBlock(*pwalletMain))
+                    {
+                        error("BitcoinMiner: Unable to sign new proof-of-work block");
+                        return;
+                    }
 
                     SetThreadPriority(THREAD_PRIORITY_NORMAL);
                     CheckWork(pblock.get(), *pwalletMain, reservekey);
diff --git a/src/main.h b/src/main.h
index 42d3759..f69c96e 100644
--- a/src/main.h
+++ b/src/main.h
@@ -98,7 +98,7 @@ void PrintBlockTree();
 bool ProcessMessages(CNode* pfrom);
 bool SendMessages(CNode* pto, bool fSendTrickle);
 void GenerateBitcoins(bool fGenerate, CWallet* pwallet);
-CBlock* CreateNewBlock(CWallet* pwallet);
+CBlock* CreateNewBlock(CWallet* pwallet, bool fProofOfWorkOnly=false);
 void IncrementExtraNonce(CBlock* pblock, CBlockIndex* pindexPrev, unsigned int& nExtraNonce);
 void FormatHashBuffers(CBlock* pblock, char* pmidstate, char* pdata, char* phash1);
 bool CheckWork(CBlock* pblock, CWallet& wallet, CReserveKey& reservekey);
-- 
1.7.1