Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

fix: delay in TimeOffset applied to AdjustedTime caused by send/recei… #28007

Closed
wants to merge 1 commit into from
Closed

fix: delay in TimeOffset applied to AdjustedTime caused by send/recei… #28007

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Jump to
Jump to file
Failed to load files.
Diff view
Diff view
60 changes: 58 additions & 2 deletions src/net.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -27,6 +27,7 @@
#include <protocol.h>
#include <random.h>
#include <scheduler.h>
#include <timedata.h>
#include <util/fs.h>
#include <util/sock.h>
#include <util/strencodings.h>
Expand All @@ -37,12 +38,18 @@

#ifdef WIN32
#include <string.h>
#else
#include <fcntl.h>
#endif

#if HAVE_DECL_GETIFADDRS && HAVE_DECL_FREEIFADDRS
#include <ifaddrs.h>
#endif

#ifdef USE_POLL
#include <poll.h>
#endif

#include <algorithm>
#include <array>
#include <cstdint>
Expand Down Expand Up @@ -825,6 +832,55 @@ size_t CConnman::SocketSendData(CNode& node) const
auto it = node.vSendMsg.begin();
size_t nSentSize = 0;

/* Begin queue send delay time offset fix
The Sendtime is not the time this message was put in the queue,
it is Now(). Observed queue delays of 30 seconds or more are introduced
on hosts with restricted resources during "tip" folloowing and chain
re-org operations. This delay corrupts AdjustedTime on the receiving host

format of VERSION message in std::deque, not contiguous
(4) message start
(12) command = version
(4) size
(4) checksum
------- chunk 2 -------
(4) nVersion
(8) nServiceInt
(8) nTime
(x) CAddress addrMe
(x) CAddress addrFrom
(8) nNonce
........ and so on...
*/
const int bigint = 1;
auto& sh = *it;
// at front of deque, hdrbuf is first
CMessageHeader * shdr = reinterpret_cast<CMessageHeader*>(sh.data());
std::string strCommand = shdr->GetCommand();
if (strCommand == NetMsgType::VERSION) {
/* do not increment "it", it corrupts deque
header and message are in 2 sequential non-contiguious chunks in the deque, see:
void CConnman::PushMessage(CNode* pnode, CSerializedNetMsg&& msg)
...
pnode->vSendMsg.push_back(std::move(serializedHeader));
if (nMessageSize)
pnode->vSendMsg.push_back(std::move(msg.data));
*/
auto& sd = *(std::next(it, 1)); // point to next data chunk
int64_t * pnsTime = reinterpret_cast<int64_t*>(sd.data() + 12);
int64_t nSendtime = *pnsTime;
int64_t nNow = GetTime();
if (node.IsInboundConn()) nNow += GetTimeOffset(); // GetAdjustedTime() in int64_t seconds
int64_t nNewSendtime = nNow;
if (! *(char *)&bigint) { // if bigendian
nSendtime = bswap_64(*pnsTime);
nNewSendtime = bswap_64(nNow);
}
// LogPrintf("HACK %s size %d %" PRId64 " %" PRId64 "\n", strCommand.c_str(), shdr->nMessageSize, nSendtime
if (nSendtime != nNow) *pnsTime = nNewSendtime;
}
// end time offset fix

while (it != node.vSendMsg.end()) {
const auto& data = *it;
assert(data.size() > node.nSendOffset);
Expand Down Expand Up @@ -2927,13 +2983,13 @@ void CaptureMessageToFile(const CAddress& addr,
AutoFile f{fsbridge::fopen(path, "ab")};

ser_writedata64(f, now.count());
f << Span{msg_type};
f.write(MakeByteSpan(msg_type));
for (auto i = msg_type.length(); i < CMessageHeader::COMMAND_SIZE; ++i) {
f << uint8_t{'\0'};
}
uint32_t size = data.size();
ser_writedata32(f, size);
f << data;
f.write(AsBytes(data));
}

std::function<void(const CAddress& addr,
Expand Down
10 changes: 9 additions & 1 deletion src/net_processing.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -3500,7 +3500,15 @@ void PeerManagerImpl::ProcessMessage(CNode& pfrom, const std::string& msg_type,
peer->m_starting_height, addrMe.ToStringAddrPort(), fRelay, pfrom.GetId(),
remoteAddr, (mapped_as ? strprintf(", mapped_as=%d", mapped_as) : ""));

int64_t nTimeOffset = nTime - GetTime();
/* Begin queue receive delay time offset fix
The receive time is not the time this message is processed, it it the time
it was put in the queue "time_received".
Observed queue delays of 30 seconds or more are introduced
on hosts with restricted resources during "tip" folloowing and chain
re-org operations. This delay corrupts AdjustedTime/
*/
// int64_t nTimeOffset = nTime - GetTime();
int64_t nTimeOffset = nTime - ((std::uint64_t)time_received.count()/1000000);
pfrom.nTimeOffset = nTimeOffset;
if (!pfrom.IsInboundConn()) {
// Don't use timedata samples from inbound peers to make it
Expand Down