Merge #7453: [0.13] Missing patches from 0.12

1e05727 Decide eviction group ties based on time. (Gregory Maxwell)
1e9613a Do not absolutely protect local peers from eviction. (Gregory Maxwell)
5d74309 Get rid of inaccurate ScriptSigArgsExpected (Pieter Wuille)

6 files changed, 16 insertions, 78 deletions

diff --git a/src/net.cpp b/src/net.cpp
index 48e9e10157..14e22f6cb3 100644
--- a/src/net.cpp
+++ b/src/net.cpp
@@ -899,8 +899,6 @@ static bool AttemptToEvictConnection(bool fPreferNewConnection) {
                 continue;
             if (node->fDisconnect)
                 continue;
-            if (node->addr.IsLocal())
-                continue;
             vEvictionCandidates.push_back(CNodeRef(node));
         }
     }
@@ -931,15 +929,20 @@ static bool AttemptToEvictConnection(bool fPreferNewConnection) {
 
     if (vEvictionCandidates.empty()) return false;
 
-    // Identify the network group with the most connections
+    // Identify the network group with the most connections and youngest member.
+    // (vEvictionCandidates is already sorted by reverse connect time)
     std::vector<unsigned char> naMostConnections;
     unsigned int nMostConnections = 0;
+    int64_t nMostConnectionsTime = 0;
     std::map<std::vector<unsigned char>, std::vector<CNodeRef> > mapAddrCounts;
     BOOST_FOREACH(const CNodeRef &node, vEvictionCandidates) {
         mapAddrCounts[node->addr.GetGroup()].push_back(node);
+        int64_t grouptime = mapAddrCounts[node->addr.GetGroup()][0]->nTimeConnected;
+        size_t groupsize = mapAddrCounts[node->addr.GetGroup()].size();
 
-        if (mapAddrCounts[node->addr.GetGroup()].size() > nMostConnections) {
-            nMostConnections = mapAddrCounts[node->addr.GetGroup()].size();
+        if (groupsize > nMostConnections || (groupsize == nMostConnections && grouptime > nMostConnectionsTime)) {
+            nMostConnections = groupsize;
+            nMostConnectionsTime = grouptime;
             naMostConnections = node->addr.GetGroup();
         }
     }
@@ -947,14 +950,13 @@ static bool AttemptToEvictConnection(bool fPreferNewConnection) {
     // Reduce to the network group with the most connections
     vEvictionCandidates = mapAddrCounts[naMostConnections];
 
-    // Do not disconnect peers if there is only 1 connection from their network group
+    // Do not disconnect peers if there is only one unprotected connection from their network group.
     if (vEvictionCandidates.size() <= 1)
         // unless we prefer the new connection (for whitelisted peers)
         if (!fPreferNewConnection)
             return false;
 
-    // Disconnect the most recent connection from the network group with the most connections
-    std::sort(vEvictionCandidates.begin(), vEvictionCandidates.end(), ReverseCompareNodeTimeConnected);
+    // Disconnect from the network group with the most connections
     vEvictionCandidates[0]->fDisconnect = true;
 
     return true;
diff --git a/src/policy/policy.cpp b/src/policy/policy.cpp
index 019df72279..332abc430e 100644
--- a/src/policy/policy.cpp
+++ b/src/policy/policy.cpp
@@ -132,45 +132,20 @@ bool AreInputsStandard(const CTransaction& tx, const CCoinsViewCache& mapInputs)
         const CScript& prevScript = prev.scriptPubKey;
         if (!Solver(prevScript, whichType, vSolutions))
             return false;
-        int nArgsExpected = ScriptSigArgsExpected(whichType, vSolutions);
-        if (nArgsExpected < 0)
-            return false;
-
-        // Transactions with extra stuff in their scriptSigs are
-        // non-standard. Note that this EvalScript() call will
-        // be quick, because if there are any operations
-        // beside "push data" in the scriptSig
-        // IsStandardTx() will have already returned false
-        // and this method isn't called.
-        std::vector<std::vector<unsigned char> > stack;
-        if (!EvalScript(stack, tx.vin[i].scriptSig, SCRIPT_VERIFY_NONE, BaseSignatureChecker()))
-            return false;
 
         if (whichType == TX_SCRIPTHASH)
         {
+            std::vector<std::vector<unsigned char> > stack;
+            // convert the scriptSig into a stack, so we can inspect the redeemScript
+            if (!EvalScript(stack, tx.vin[i].scriptSig, SCRIPT_VERIFY_NONE, BaseSignatureChecker(), 0))
+                return false;
             if (stack.empty())
                 return false;
             CScript subscript(stack.back().begin(), stack.back().end());
-            std::vector<std::vector<unsigned char> > vSolutions2;
-            txnouttype whichType2;
-            if (Solver(subscript, whichType2, vSolutions2))
-            {
-                int tmpExpected = ScriptSigArgsExpected(whichType2, vSolutions2);
-                if (tmpExpected < 0)
-                    return false;
-                nArgsExpected += tmpExpected;
-            }
-            else
-            {
-                // Any other Script with less than 15 sigops OK:
-                unsigned int sigops = subscript.GetSigOpCount(true);
-                // ... extra data left on the stack after execution is OK, too:
-                return (sigops <= MAX_P2SH_SIGOPS);
+            if (subscript.GetSigOpCount(true) > MAX_P2SH_SIGOPS) {
+                return false;
             }
         }
-
-        if (stack.size() != (unsigned int)nArgsExpected)
-            return false;
     }
 
     return true;
diff --git a/src/script/standard.cpp b/src/script/standard.cpp
index 30935768ac..67b6af327a 100644
--- a/src/script/standard.cpp
+++ b/src/script/standard.cpp
@@ -161,27 +161,6 @@ bool Solver(const CScript& scriptPubKey, txnouttype& typeRet, vector<vector<unsi
     return false;
 }
 
-int ScriptSigArgsExpected(txnouttype t, const std::vector<std::vector<unsigned char> >& vSolutions)
-{
-    switch (t)
-    {
-    case TX_NONSTANDARD:
-    case TX_NULL_DATA:
-        return -1;
-    case TX_PUBKEY:
-        return 1;
-    case TX_PUBKEYHASH:
-        return 2;
-    case TX_MULTISIG:
-        if (vSolutions.size() < 1 || vSolutions[0].size() < 1)
-            return -1;
-        return vSolutions[0][0] + 1;
-    case TX_SCRIPTHASH:
-        return 1; // doesn't include args needed by the script
-    }
-    return -1;
-}
-
 bool ExtractDestination(const CScript& scriptPubKey, CTxDestination& addressRet)
 {
     vector<valtype> vSolutions;
diff --git a/src/script/standard.h b/src/script/standard.h
index 6bac6e4097..64bf010ec1 100644
--- a/src/script/standard.h
+++ b/src/script/standard.h
@@ -71,7 +71,6 @@ typedef boost::variant<CNoDestination, CKeyID, CScriptID> CTxDestination;
 const char* GetTxnOutputType(txnouttype t);
 
 bool Solver(const CScript& scriptPubKey, txnouttype& typeRet, std::vector<std::vector<unsigned char> >& vSolutionsRet);
-int ScriptSigArgsExpected(txnouttype t, const std::vector<std::vector<unsigned char> >& vSolutions);
 bool ExtractDestination(const CScript& scriptPubKey, CTxDestination& addressRet);
 bool ExtractDestinations(const CScript& scriptPubKey, txnouttype& typeRet, std::vector<CTxDestination>& addressRet, int& nRequiredRet);
 
diff --git a/src/test/script_P2SH_tests.cpp b/src/test/script_P2SH_tests.cpp
index 7bd4b8441b..28b85e8d29 100644
--- a/src/test/script_P2SH_tests.cpp
+++ b/src/test/script_P2SH_tests.cpp
@@ -346,15 +346,6 @@ BOOST_AUTO_TEST_CASE(AreInputsStandard)
     // 22 P2SH sigops for all inputs (1 for vin[0], 6 for vin[3], 15 for vin[4]
     BOOST_CHECK_EQUAL(GetP2SHSigOpCount(txTo, coins), 22U);
 
-    // Make sure adding crap to the scriptSigs makes them non-standard:
-    for (int i = 0; i < 3; i++)
-    {
-        CScript t = txTo.vin[i].scriptSig;
-        txTo.vin[i].scriptSig = (CScript() << 11) + t;
-        BOOST_CHECK(!::AreInputsStandard(txTo, coins));
-        txTo.vin[i].scriptSig = t;
-    }
-
     CMutableTransaction txToNonStd1;
     txToNonStd1.vout.resize(1);
     txToNonStd1.vout[0].scriptPubKey = GetScriptForDestination(key[1].GetPubKey().GetID());
diff --git a/src/test/transaction_tests.cpp b/src/test/transaction_tests.cpp
index 3dca7ea0f7..c27f194b55 100644
--- a/src/test/transaction_tests.cpp
+++ b/src/test/transaction_tests.cpp
@@ -310,14 +310,6 @@ BOOST_AUTO_TEST_CASE(test_Get)
 
     BOOST_CHECK(AreInputsStandard(t1, coins));
     BOOST_CHECK_EQUAL(coins.GetValueIn(t1), (50+21+22)*CENT);
-
-    // Adding extra junk to the scriptSig should make it non-standard:
-    t1.vin[0].scriptSig << OP_11;
-    BOOST_CHECK(!AreInputsStandard(t1, coins));
-
-    // ... as should not having enough:
-    t1.vin[0].scriptSig = CScript();
-    BOOST_CHECK(!AreInputsStandard(t1, coins));
 }
 
 BOOST_AUTO_TEST_CASE(test_IsStandard)