// Copyright (c) 2009-2010 Satoshi Nakamoto
// Copyright (c) 2009-2012 The Bitcoin developers
+// Copyright (c) 2012 The PPCoin developers
// Distributed under the MIT/X11 software license, see the accompanying
-// file license.txt or http://www.opensource.org/licenses/mit-license.php.
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#include <boost/foreach.hpp>
+#include <boost/tuple/tuple.hpp>
using namespace std;
using namespace boost;
#include "bignum.h"
#include "key.h"
#include "main.h"
+#include "util.h"
bool CheckSig(vector<unsigned char> vchSig, vector<unsigned char> vchPubKey, CScript scriptCode, const CTransaction& txTo, unsigned int nIn, int nHashType);
-typedef vector<unsigned char> valtype;
static const valtype vchFalse(0);
static const valtype vchZero(0);
static const valtype vchTrue(1, 1);
return false;
int n = CastToBigNum(stacktop(-1)).getint();
popstack(stack);
- if (n < 0 || n >= stack.size())
+ if (n < 0 || n >= (int)stack.size())
return false;
valtype vch = stacktop(-n-1);
if (opcode == OP_ROLL)
int nEnd = nBegin + CastToBigNum(stacktop(-1)).getint();
if (nBegin < 0 || nEnd < nBegin)
return false;
- if (nBegin > vch.size())
+ if (nBegin > (int)vch.size())
nBegin = vch.size();
- if (nEnd > vch.size())
+ if (nEnd > (int)vch.size())
nEnd = vch.size();
vch.erase(vch.begin() + nEnd, vch.end());
vch.erase(vch.begin(), vch.begin() + nBegin);
int nSize = CastToBigNum(stacktop(-1)).getint();
if (nSize < 0)
return false;
- if (nSize > vch.size())
+ if (nSize > (int)vch.size())
nSize = vch.size();
if (opcode == OP_LEFT)
vch.erase(vch.begin() + nSize, vch.end());
{
// ([sig ...] num_of_signatures [pubkey ...] num_of_pubkeys -- bool)
- unsigned int i = 1;
+ int i = 1;
if (stack.size() < i)
return false;
}
+// Valid signature cache, to avoid doing expensive ECDSA signature checking
+// twice for every transaction (once when accepted into memory pool, and
+// again when accepted into the block chain)
+
+class CSignatureCache
+{
+private:
+ // sigdata_type is (signature hash, signature, public key):
+ typedef boost::tuple<uint256, std::vector<unsigned char>, std::vector<unsigned char> > sigdata_type;
+ std::set< sigdata_type> setValid;
+ CCriticalSection cs_sigcache;
+
+public:
+ bool
+ Get(uint256 hash, const std::vector<unsigned char>& vchSig, const std::vector<unsigned char>& pubKey)
+ {
+ LOCK(cs_sigcache);
+
+ sigdata_type k(hash, vchSig, pubKey);
+ std::set<sigdata_type>::iterator mi = setValid.find(k);
+ if (mi != setValid.end())
+ return true;
+ return false;
+ }
+
+ void
+ Set(uint256 hash, const std::vector<unsigned char>& vchSig, const std::vector<unsigned char>& pubKey)
+ {
+ // DoS prevention: limit cache size to less than 10MB
+ // (~200 bytes per cache entry times 50,000 entries)
+ // Since there are a maximum of 20,000 signature operations per block
+ // 50,000 is a reasonable default.
+ int64 nMaxCacheSize = GetArg("-maxsigcachesize", 50000);
+ if (nMaxCacheSize <= 0) return;
+
+ LOCK(cs_sigcache);
+
+ while (static_cast<int64>(setValid.size()) > nMaxCacheSize)
+ {
+ // Evict a random entry. Random because that helps
+ // foil would-be DoS attackers who might try to pre-generate
+ // and re-use a set of valid signatures just-slightly-greater
+ // than our cache size.
+ uint256 randomHash = GetRandHash();
+ std::vector<unsigned char> unused;
+ std::set<sigdata_type>::iterator it =
+ setValid.lower_bound(sigdata_type(randomHash, unused, unused));
+ if (it == setValid.end())
+ it = setValid.begin();
+ setValid.erase(*it);
+ }
+
+ sigdata_type k(hash, vchSig, pubKey);
+ setValid.insert(k);
+ }
+};
+
bool CheckSig(vector<unsigned char> vchSig, vector<unsigned char> vchPubKey, CScript scriptCode,
const CTransaction& txTo, unsigned int nIn, int nHashType)
{
- CKey key;
- if (!key.SetPubKey(vchPubKey))
- return false;
+ static CSignatureCache signatureCache;
// Hash type is one byte tacked on to the end of the signature
if (vchSig.empty())
return false;
vchSig.pop_back();
- return key.Verify(SignatureHash(scriptCode, txTo, nIn, nHashType), vchSig);
+ uint256 sighash = SignatureHash(scriptCode, txTo, nIn, nHashType);
+
+ if (signatureCache.Get(sighash, vchSig, vchPubKey))
+ return true;
+
+ CKey key;
+ if (!key.SetPubKey(vchPubKey))
+ return false;
+
+ if (!key.Verify(sighash, vchSig))
+ return false;
+
+ signatureCache.Set(sighash, vchSig, vchPubKey);
+ return true;
}
}
-int HaveKeys(const vector<valtype>& pubkeys, const CKeyStore& keystore)
+unsigned int HaveKeys(const vector<valtype>& pubkeys, const CKeyStore& keystore)
{
- int nResult = 0;
+ unsigned int nResult = 0;
BOOST_FOREACH(const valtype& pubkey, pubkeys)
{
CBitcoinAddress address;
assert(nIn < txTo.vin.size());
CTxIn& txin = txTo.vin[nIn];
assert(txin.prevout.n < txFrom.vout.size());
+ assert(txin.prevout.hash == txFrom.GetHash());
const CTxOut& txout = txFrom.vout[txin.prevout.n];
// Leave out the signature from the hash, since a signature can't sign itself.
return true;
}
-int CScript::GetSigOpCount(bool fAccurate) const
+unsigned int CScript::GetSigOpCount(bool fAccurate) const
{
- int n = 0;
+ unsigned int n = 0;
const_iterator pc = begin();
opcodetype lastOpcode = OP_INVALIDOPCODE;
while (pc < end())
return n;
}
-int CScript::GetSigOpCount(const CScript& scriptSig) const
+unsigned int CScript::GetSigOpCount(const CScript& scriptSig) const
{
if (!IsPayToScriptHash())
return GetSigOpCount(true);
git://git.novaco.in / novacoin.git / blobdiff