aboutsummaryrefslogtreecommitdiff
path: root/src
diff options
context:
space:
mode:
authorSebastian Falbesoner <sebastian.falbesoner@gmail.com>2020-04-28 19:19:34 +0200
committerSebastian Falbesoner <sebastian.falbesoner@gmail.com>2020-04-28 19:27:22 +0200
commit1ad8ea2b73134bdd8d6b50704a019d47ad2191d8 (patch)
treee4bb3deda313169ce6e76178df16d78a2bb7ae2d /src
parent6e3fc7492a7d5e58c0ada22617388b6487410f82 (diff)
net: remove is{Empty,Full} flags from CBloomFilter, clarify CVE fix
Diffstat (limited to 'src')
-rw-r--r--src/bloom.cpp26
-rw-r--r--src/bloom.h7
-rw-r--r--src/net_processing.cpp1
-rw-r--r--src/test/fuzz/bloom_filter.cpp5
4 files changed, 5 insertions, 34 deletions
diff --git a/src/bloom.cpp b/src/bloom.cpp
index 30af507243..54fcf487e4 100644
--- a/src/bloom.cpp
+++ b/src/bloom.cpp
@@ -31,8 +31,6 @@ CBloomFilter::CBloomFilter(const unsigned int nElements, const double nFPRate, c
* Again, we ignore filter parameters which will create a bloom filter with more hash functions than the protocol limits
* See https://en.wikipedia.org/wiki/Bloom_filter for an explanation of these formulas
*/
- isFull(false),
- isEmpty(true),
nHashFuncs(std::min((unsigned int)(vData.size() * 8 / nElements * LN2), MAX_HASH_FUNCS)),
nTweak(nTweakIn),
nFlags(nFlagsIn)
@@ -47,7 +45,7 @@ inline unsigned int CBloomFilter::Hash(unsigned int nHashNum, const std::vector<
void CBloomFilter::insert(const std::vector<unsigned char>& vKey)
{
- if (isFull)
+ if (vData.empty()) // Avoid divide-by-zero (CVE-2013-5700)
return;
for (unsigned int i = 0; i < nHashFuncs; i++)
{
@@ -55,7 +53,6 @@ void CBloomFilter::insert(const std::vector<unsigned char>& vKey)
// Sets bit nIndex of vData
vData[nIndex >> 3] |= (1 << (7 & nIndex));
}
- isEmpty = false;
}
void CBloomFilter::insert(const COutPoint& outpoint)
@@ -74,10 +71,8 @@ void CBloomFilter::insert(const uint256& hash)
bool CBloomFilter::contains(const std::vector<unsigned char>& vKey) const
{
- if (isFull)
+ if (vData.empty()) // Avoid divide-by-zero (CVE-2013-5700)
return true;
- if (isEmpty)
- return false;
for (unsigned int i = 0; i < nHashFuncs; i++)
{
unsigned int nIndex = Hash(i, vKey);
@@ -112,10 +107,8 @@ bool CBloomFilter::IsRelevantAndUpdate(const CTransaction& tx)
bool fFound = false;
// Match if the filter contains the hash of tx
// for finding tx when they appear in a block
- if (isFull)
+ if (vData.empty()) // zero-size = "match-all" filter
return true;
- if (isEmpty)
- return false;
const uint256& hash = tx.GetHash();
if (contains(hash))
fFound = true;
@@ -177,19 +170,6 @@ bool CBloomFilter::IsRelevantAndUpdate(const CTransaction& tx)
return false;
}
-void CBloomFilter::UpdateEmptyFull()
-{
- bool full = true;
- bool empty = true;
- for (unsigned int i = 0; i < vData.size(); i++)
- {
- full &= vData[i] == 0xff;
- empty &= vData[i] == 0;
- }
- isFull = full;
- isEmpty = empty;
-}
-
CRollingBloomFilter::CRollingBloomFilter(const unsigned int nElements, const double fpRate)
{
double logFpRate = log(fpRate);
diff --git a/src/bloom.h b/src/bloom.h
index 8e3b7be54d..9173b80d66 100644
--- a/src/bloom.h
+++ b/src/bloom.h
@@ -45,8 +45,6 @@ class CBloomFilter
{
private:
std::vector<unsigned char> vData;
- bool isFull;
- bool isEmpty;
unsigned int nHashFuncs;
unsigned int nTweak;
unsigned char nFlags;
@@ -64,7 +62,7 @@ public:
* nFlags should be one of the BLOOM_UPDATE_* enums (not _MASK)
*/
CBloomFilter(const unsigned int nElements, const double nFPRate, const unsigned int nTweak, unsigned char nFlagsIn);
- CBloomFilter() : isFull(true), isEmpty(false), nHashFuncs(0), nTweak(0), nFlags(0) {}
+ CBloomFilter() : nHashFuncs(0), nTweak(0), nFlags(0) {}
ADD_SERIALIZE_METHODS;
@@ -90,9 +88,6 @@ public:
//! Also adds any outputs which match the filter to the filter (to match their spending txes)
bool IsRelevantAndUpdate(const CTransaction& tx);
-
- //! Checks for empty and full filters to avoid wasting cpu
- void UpdateEmptyFull();
};
/**
diff --git a/src/net_processing.cpp b/src/net_processing.cpp
index 26327ac6eb..34017bc047 100644
--- a/src/net_processing.cpp
+++ b/src/net_processing.cpp
@@ -3193,7 +3193,6 @@ bool ProcessMessage(CNode* pfrom, const std::string& msg_type, CDataStream& vRec
{
LOCK(pfrom->m_tx_relay->cs_filter);
pfrom->m_tx_relay->pfilter.reset(new CBloomFilter(filter));
- pfrom->m_tx_relay->pfilter->UpdateEmptyFull();
pfrom->m_tx_relay->fRelayTxes = true;
}
return true;
diff --git a/src/test/fuzz/bloom_filter.cpp b/src/test/fuzz/bloom_filter.cpp
index 50036ce5bd..7039bf16c1 100644
--- a/src/test/fuzz/bloom_filter.cpp
+++ b/src/test/fuzz/bloom_filter.cpp
@@ -25,7 +25,7 @@ void test_one_input(const std::vector<uint8_t>& buffer)
fuzzed_data_provider.ConsumeIntegral<unsigned int>(),
static_cast<unsigned char>(fuzzed_data_provider.PickValueInArray({BLOOM_UPDATE_NONE, BLOOM_UPDATE_ALL, BLOOM_UPDATE_P2PUBKEY_ONLY, BLOOM_UPDATE_MASK}))};
while (fuzzed_data_provider.remaining_bytes() > 0) {
- switch (fuzzed_data_provider.ConsumeIntegralInRange(0, 4)) {
+ switch (fuzzed_data_provider.ConsumeIntegralInRange(0, 3)) {
case 0: {
const std::vector<unsigned char> b = ConsumeRandomLengthByteVector(fuzzed_data_provider);
(void)bloom_filter.contains(b);
@@ -65,9 +65,6 @@ void test_one_input(const std::vector<uint8_t>& buffer)
(void)bloom_filter.IsRelevantAndUpdate(tx);
break;
}
- case 4:
- bloom_filter.UpdateEmptyFull();
- break;
}
(void)bloom_filter.IsWithinSizeConstraints();
}