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Remove timing-based signature cache unit test

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Two changes:

First removes a unit test that fails in my development environment
(OSX, compiled -g3 with clang).

sipa says that's not terribly surprising; the CMutableTransaction change
makes signing a little more expensive but verification quicker. The unit
test timed sign+verify-uncached versus verify-cached-five-times.

He also says the test will be invalid when libsec256kp1 is integrated
(because validation is super-optimized over signing).

core.h change fixes a compiler warning (clang -Wall : CMutableTransaction defined
as struct, declared as class in script.h).
This commit is contained in:
Gavin Andresen 2014-06-25 14:21:29 -04:00
parent 343feecf56
commit a90689ff98
No known key found for this signature in database
GPG key ID: 7588242FBE38D3A8
2 changed files with 1 additions and 88 deletions
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2
src/script.h
View file

@ -20,7 +20,7 @@
class CCoins; class CCoins;
class CKeyStore; class CKeyStore;
class CTransaction; class CTransaction;
class CMutableTransaction; struct CMutableTransaction;
static const unsigned int MAX_SCRIPT_ELEMENT_SIZE = 520; // bytes static const unsigned int MAX_SCRIPT_ELEMENT_SIZE = 520; // bytes
static const unsigned int MAX_OP_RETURN_RELAY = 40; // bytes static const unsigned int MAX_OP_RETURN_RELAY = 40; // bytes

87
src/test/DoS_tests.cpp
View file

@ -231,91 +231,4 @@ BOOST_AUTO_TEST_CASE(DoS_mapOrphans)
BOOST_CHECK(mapOrphanTransactionsByPrev.empty()); BOOST_CHECK(mapOrphanTransactionsByPrev.empty());
} }
BOOST_AUTO_TEST_CASE(DoS_checkSig)
{
// Test signature caching code (see key.cpp Verify() methods)
CKey key;
key.MakeNewKey(true);
CBasicKeyStore keystore;
keystore.AddKey(key);
unsigned int flags = SCRIPT_VERIFY_P2SH | SCRIPT_VERIFY_STRICTENC;
// 100 orphan transactions:
static const int NPREV=100;
CMutableTransaction orphans[NPREV];
for (int i = 0; i < NPREV; i++)
{
CMutableTransaction& tx = orphans[i];
tx.vin.resize(1);
tx.vin[0].prevout.n = 0;
tx.vin[0].prevout.hash = GetRandHash();
tx.vin[0].scriptSig << OP_1;
tx.vout.resize(1);
tx.vout[0].nValue = 1*CENT;
tx.vout[0].scriptPubKey.SetDestination(key.GetPubKey().GetID());
AddOrphanTx(tx);
}
// Create a transaction that depends on orphans:
CMutableTransaction tx;
tx.vout.resize(1);
tx.vout[0].nValue = 1*CENT;
tx.vout[0].scriptPubKey.SetDestination(key.GetPubKey().GetID());
tx.vin.resize(NPREV);
for (unsigned int j = 0; j < tx.vin.size(); j++)
{
tx.vin[j].prevout.n = 0;
tx.vin[j].prevout.hash = orphans[j].GetHash();
}
// Creating signatures primes the cache:
boost::posix_time::ptime mst1 = boost::posix_time::microsec_clock::local_time();
for (unsigned int j = 0; j < tx.vin.size(); j++)
BOOST_CHECK(SignSignature(keystore, orphans[j], tx, j));
boost::posix_time::ptime mst2 = boost::posix_time::microsec_clock::local_time();
boost::posix_time::time_duration msdiff = mst2 - mst1;
long nOneValidate = msdiff.total_milliseconds();
if (fDebug) printf("DoS_Checksig sign: %ld\n", nOneValidate);
// ... now validating repeatedly should be quick:
// 2.8GHz machine, -g build: Sign takes ~760ms,
// uncached Verify takes ~250ms, cached Verify takes ~50ms
// (for 100 single-signature inputs)
mst1 = boost::posix_time::microsec_clock::local_time();
for (unsigned int i = 0; i < 5; i++)
for (unsigned int j = 0; j < tx.vin.size(); j++)
BOOST_CHECK(VerifySignature(CCoins(orphans[j], MEMPOOL_HEIGHT), tx, j, flags, SIGHASH_ALL));
mst2 = boost::posix_time::microsec_clock::local_time();
msdiff = mst2 - mst1;
long nManyValidate = msdiff.total_milliseconds();
if (fDebug) printf("DoS_Checksig five: %ld\n", nManyValidate);
BOOST_CHECK_MESSAGE(nManyValidate < nOneValidate, "Signature cache timing failed");
// Empty a signature, validation should fail:
CScript save = tx.vin[0].scriptSig;
tx.vin[0].scriptSig = CScript();
BOOST_CHECK(!VerifySignature(CCoins(orphans[0], MEMPOOL_HEIGHT), tx, 0, flags, SIGHASH_ALL));
tx.vin[0].scriptSig = save;
// Swap signatures, validation should fail:
std::swap(tx.vin[0].scriptSig, tx.vin[1].scriptSig);
BOOST_CHECK(!VerifySignature(CCoins(orphans[0], MEMPOOL_HEIGHT), tx, 0, flags, SIGHASH_ALL));
BOOST_CHECK(!VerifySignature(CCoins(orphans[1], MEMPOOL_HEIGHT), tx, 1, flags, SIGHASH_ALL));
std::swap(tx.vin[0].scriptSig, tx.vin[1].scriptSig);
// Exercise -maxsigcachesize code:
mapArgs["-maxsigcachesize"] = "10";
// Generate a new, different signature for vin[0] to trigger cache clear:
CScript oldSig = tx.vin[0].scriptSig;
BOOST_CHECK(SignSignature(keystore, orphans[0], tx, 0));
BOOST_CHECK(tx.vin[0].scriptSig != oldSig);
for (unsigned int j = 0; j < tx.vin.size(); j++)
BOOST_CHECK(VerifySignature(CCoins(orphans[j], MEMPOOL_HEIGHT), tx, j, flags, SIGHASH_ALL));
mapArgs.erase("-maxsigcachesize");
LimitOrphanTxSize(0);
}
BOOST_AUTO_TEST_SUITE_END() BOOST_AUTO_TEST_SUITE_END()