X-Git-Url: https://git.novaco.in/?p=novacoin.git;a=blobdiff_plain;f=src%2Fkey.cpp;h=b6c3f2868825f7b506aaf3b240a822eb09c50483;hp=ac7ac4db775670888f3b2a574460708f2bcbbc4d;hb=fcbeaff8d049e414284631989b950e56b909525c;hpb=414e0407df38ccde3f20aac874005aec714299d0 diff --git a/src/key.cpp b/src/key.cpp index ac7ac4d..b6c3f28 100644 --- a/src/key.cpp +++ b/src/key.cpp @@ -4,7 +4,6 @@ #include -#include #include #include @@ -351,85 +350,23 @@ bool CKey::SetCompactSignature(uint256 hash, const std::vector& v 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) - -// sigdata_type is (signature hash, signature, public key): -typedef boost::tuple, std::vector > sigdata_type; -static std::set< sigdata_type> setValidSigCache; -static CCriticalSection cs_sigcache; - -static bool -GetValidSigCache(uint256 hash, const std::vector& vchSig, const std::vector& pubKey) -{ - LOCK(cs_sigcache); - - sigdata_type k(hash, vchSig, pubKey); - std::set::iterator mi = setValidSigCache.find(k); - if (mi != setValidSigCache.end()) - return true; - return false; -} - -static void -SetValidSigCache(uint256 hash, const std::vector& vchSig, const std::vector& 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 (setValidSigCache.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 unused; - std::set::iterator it = - setValidSigCache.lower_bound(sigdata_type(randomHash, unused, unused)); - if (it == setValidSigCache.end()) - it = setValidSigCache.begin(); - setValidSigCache.erase(*it); - } - - sigdata_type k(hash, vchSig, pubKey); - setValidSigCache.insert(k); -} - - bool CKey::Verify(uint256 hash, const std::vector& vchSig) { - if (GetValidSigCache(hash, vchSig, GetPubKey())) - return true; - // -1 = error, 0 = bad sig, 1 = good if (ECDSA_verify(0, (unsigned char*)&hash, sizeof(hash), &vchSig[0], vchSig.size(), pkey) != 1) return false; - // good sig - SetValidSigCache(hash, vchSig, GetPubKey()); return true; } bool CKey::VerifyCompact(uint256 hash, const std::vector& vchSig) { - if (GetValidSigCache(hash, vchSig, GetPubKey())) - return true; - CKey key; if (!key.SetCompactSignature(hash, vchSig)) return false; if (GetPubKey() != key.GetPubKey()) return false; - SetValidSigCache(hash, vchSig, GetPubKey()); return true; }