Files
rippled/modules/ripple_app/misc/ripple_ProofOfWorkFactory.cpp
2013-07-29 14:28:03 -07:00

313 lines
10 KiB
C++

//------------------------------------------------------------------------------
/*
Copyright (c) 2011-2013, OpenCoin, Inc.
*/
//==============================================================================
ProofOfWorkFactory::ProofOfWorkFactory () : mValidTime (180)
{
setDifficulty (1);
RandomNumbers::getInstance ().fillBytes (mSecret.begin (), mSecret.size ());
}
ProofOfWork ProofOfWorkFactory::getProof ()
{
// challenge - target - iterations - time - validator
static boost::format f ("%s-%s-%d-%d");
int now = static_cast<int> (time (NULL) / 4);
uint256 challenge;
RandomNumbers::getInstance ().fillBytes (challenge.begin (), challenge.size ());
boost::mutex::scoped_lock sl (mLock);
std::string s = boost::str (boost::format (f) % challenge.GetHex () % mTarget.GetHex () % mIterations % now);
std::string c = mSecret.GetHex () + s;
s += "-" + Serializer::getSHA512Half (c).GetHex ();
return ProofOfWork (s, mIterations, challenge, mTarget);
}
POWResult ProofOfWorkFactory::checkProof (const std::string& token, uint256 const& solution)
{
// VFALCO COmmented this out because Dave said it wasn't used
// and also we dont have the lexicalCast from a vector of strings to a time_t
// challenge - target - iterations - time - validator
std::vector<std::string> fields;
boost::split (fields, token, boost::algorithm::is_any_of ("-"));
if (fields.size () != 5)
{
WriteLog (lsDEBUG, ProofOfWork) << "PoW " << token << " is corrupt";
return powCORRUPT;
}
std::string v = mSecret.GetHex () + fields[0] + "-" + fields[1] + "-" + fields[2] + "-" + fields[3];
if (fields[4] != Serializer::getSHA512Half (v).GetHex ())
{
WriteLog (lsDEBUG, ProofOfWork) << "PoW " << token << " has a bad token";
return powCORRUPT;
}
uint256 challenge, target;
challenge.SetHex (fields[0]);
target.SetHex (fields[1]);
time_t t;
#if 0
// Broken with lexicalCast<> changes
t = lexicalCast <time_t> (fields[3]);
#else
t = static_cast <time_t> (lexicalCast <uint64> (fields [3]));
#endif
time_t now = time (NULL);
int iterations = lexicalCast <int> (fields[2]);
{
boost::mutex::scoped_lock sl (mLock);
if ((t * 4) > (now + mValidTime))
{
WriteLog (lsDEBUG, ProofOfWork) << "PoW " << token << " has expired";
return powEXPIRED;
}
if (((iterations != mIterations) || (target != mTarget)) && getPowEntry (target, iterations) < (mPowEntry - 2))
{
// difficulty has increased more than two times since PoW requested
WriteLog (lsINFO, ProofOfWork) << "Difficulty has increased since PoW requested";
return powTOOEASY;
}
}
ProofOfWork pow (token, iterations, challenge, target);
if (!pow.checkSolution (solution))
{
WriteLog (lsDEBUG, ProofOfWork) << "PoW " << token << " has a bad nonce";
return powBADNONCE;
}
{
boost::mutex::scoped_lock sl (mLock);
if (!mSolvedChallenges.insert (powMap_vt (now, challenge)).second)
{
WriteLog (lsDEBUG, ProofOfWork) << "PoW " << token << " has been reused";
return powREUSED;
}
}
return powOK;
}
void ProofOfWorkFactory::sweep ()
{
time_t expire = time (NULL) - mValidTime;
boost::mutex::scoped_lock sl (mLock);
do
{
powMap_t::left_map::iterator it = mSolvedChallenges.left.begin ();
if (it == mSolvedChallenges.left.end ())
return;
if (it->first >= expire)
return;
mSolvedChallenges.left.erase (it);
}
while (1);
}
void ProofOfWorkFactory::loadHigh ()
{
time_t now = time (NULL);
boost::mutex::scoped_lock sl (mLock);
if (mLastDifficultyChange == now)
return;
if (mPowEntry == 30)
return;
++mPowEntry;
mLastDifficultyChange = now;
}
void ProofOfWorkFactory::loadLow ()
{
time_t now = time (NULL);
boost::mutex::scoped_lock sl (mLock);
if (mLastDifficultyChange == now)
return;
if (mPowEntry == 0)
return;
--mPowEntry;
mLastDifficultyChange = now;
}
struct PowEntry
{
const char* target;
int iterations;
};
PowEntry PowEntries[ProofOfWork::sMaxDifficulty + 1] =
{
// target iterations hashes memory
{ "0CFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF", 65536 }, // 1451874, 2 MB
{ "0CFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF", 98304 }, // 2177811, 3 MB
{ "07FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF", 98304 }, // 3538944, 3 MB
{ "0CFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF", 196608}, // 4355623, 6 MB
{ "07FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF", 131072}, // 4718592, 4 MB
{ "0CFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF", 262144}, // 5807497, 8 MB
{ "07FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF", 196608}, // 7077888, 6 MB
{ "07FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF", 262144}, // 9437184, 8 MB
{ "07FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF", 393216}, // 14155776, 12MB
{ "03FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF", 393216}, // 28311552, 12MB
{ "00CFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF", 262144}, // 92919965, 8 MB
{ "00CFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF", 393216}, // 139379948, 12MB
{ "007FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF", 262144}, // 150994944, 8 MB
{ "007FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF", 393216}, // 226492416, 12MB
{ "000CFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF", 49152 }, // 278759896, 1.5MB
{ "003FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF", 262144}, // 301989888, 8 MB
{ "003FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF", 393216}, // 452984832, 12MB
{ "0007FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF", 98304 }, // 905969664, 3 MB
{ "000CFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF", 196608}, // 1115039586, 6 MB
{ "000CFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF", 262144}, // 1486719448 8 MB
{ "000CFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF", 393216}, // 2230079172 12MB
{ "0007FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF", 262144}, // 2415919104, 8 MB
{ "0007FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF", 393216}, // 3623878656, 12MB
{ "0003FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF", 393216}, // 7247757312, 12MB
{ "0000CFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF", 262144}, // 23787511177, 8 MB
{ "0000CFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF", 393216}, // 35681266766, 12MB
{ "00003FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF", 131072}, // 38654705664, 4 MB
{ "00007FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF", 262144}, // 38654705664, 8 MB
{ "00003FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF", 196608}, // 57982058496, 6 MB
{ "00007FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF", 393216}, // 57982058496, 12MB
{ "00003FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF", 262144}, // 77309411328, 8 MB
};
int ProofOfWorkFactory::getPowEntry (uint256 const& target, int iterations)
{
for (int i = 0; i < 31; ++i)
if (PowEntries[i].iterations == iterations)
{
uint256 t;
t.SetHex (PowEntries[i].target);
if (t == target)
return i;
}
return -1;
}
void ProofOfWorkFactory::setDifficulty (int i)
{
assert ((i >= 0) && (i <= ProofOfWork::sMaxDifficulty));
time_t now = time (NULL);
boost::mutex::scoped_lock sl (mLock);
mPowEntry = i;
mIterations = PowEntries[i].iterations;
mTarget.SetHex (PowEntries[i].target);
mLastDifficultyChange = now;
}
IProofOfWorkFactory* IProofOfWorkFactory::New ()
{
return new ProofOfWorkFactory;
}
//------------------------------------------------------------------------------
class ProofOfWorkTests : public UnitTest
{
public:
ProofOfWorkTests () : UnitTest ("ProofOfWork", "ripple")
{
}
void runTest ()
{
using namespace ripple;
ProofOfWorkFactory gen;
ProofOfWork pow = gen.getProof ();
String s;
s << "solve difficulty " << String (pow.getDifficulty ());
beginTestCase ("solve");
uint256 solution = pow.solve (16777216);
expect (! solution.isZero (), "Should be solved");
expect (pow.checkSolution (solution), "Should be checked");
// Why is this emitted?
//WriteLog (lsDEBUG, ProofOfWork) << "A bad nonce error is expected";
POWResult r = gen.checkProof (pow.getToken (), uint256 ());
expect (r == powBADNONCE, "Should show bad nonce for empty solution");
expect (gen.checkProof (pow.getToken (), solution) == powOK, "Solution should check with issuer");
//WriteLog (lsDEBUG, ProofOfWork) << "A reused nonce error is expected";
expect (gen.checkProof (pow.getToken (), solution) == powREUSED, "Reuse solution should be detected");
#ifdef SOLVE_POWS
for (int i = 0; i < 12; ++i)
{
gen.setDifficulty (i);
ProofOfWork pow = gen.getProof ();
WriteLog (lsINFO, ProofOfWork) << "Level: " << i << ", Estimated difficulty: " << pow.getDifficulty ();
uint256 solution = pow.solve (131072);
if (solution.isZero ())
{
//WriteLog (lsINFO, ProofOfWork) << "Giving up";
}
else
{
//WriteLog (lsINFO, ProofOfWork) << "Solution found";
if (gen.checkProof (pow.getToken (), solution) != powOK)
{
//WriteLog (lsFATAL, ProofOfWork) << "Solution fails";
}
}
}
#endif
}
};
static ProofOfWorkTests proofOfWorkTests;