1 // Copyright (c) 2024-present The Bitcoin Core developers
2 // Distributed under the MIT software license, see the accompanying
3 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
4 5 #include <node/timeoffsets.h>
6 #include <node/warnings.h>
7 #include <sync.h>
8 #include <tinyformat.h>
9 #include <util/log.h>
10 #include <util/time.h>
11 #include <util/translation.h>
12 13 #include <algorithm>
14 #include <chrono>
15 #include <cstdint>
16 #include <deque>
17 #include <limits>
18 #include <optional>
19 20 using namespace std::chrono_literals;
21 22 void TimeOffsets::Add(std::chrono::seconds offset)
23 {
24 LOCK(m_mutex);
25 26 if (m_offsets.size() >= MAX_SIZE) {
27 m_offsets.pop_front();
28 }
29 m_offsets.push_back(offset);
30 LogDebug(BCLog::NET, "Added time offset %+ds, total samples %d\n",
31 Ticks<std::chrono::seconds>(offset), m_offsets.size());
32 }
33 34 std::chrono::seconds TimeOffsets::Median() const
35 {
36 LOCK(m_mutex);
37 38 // Only calculate the median if we have 5 or more offsets
39 if (m_offsets.size() < 5) return 0s;
40 41 auto sorted_copy = m_offsets;
42 std::sort(sorted_copy.begin(), sorted_copy.end());
43 return sorted_copy[sorted_copy.size() / 2]; // approximate median is good enough, keep it simple
44 }
45 46 bool TimeOffsets::WarnIfOutOfSync() const
47 {
48 // when median == std::numeric_limits<int64_t>::min(), calling std::chrono::abs is UB
49 auto median{std::max(Median(), std::chrono::seconds(std::numeric_limits<int64_t>::min() + 1))};
50 if (std::chrono::abs(median) <= WARN_THRESHOLD) {
51 m_warnings.Unset(node::Warning::CLOCK_OUT_OF_SYNC);
52 return false;
53 }
54 55 bilingual_str msg{strprintf(_(
56 "Your computer's date and time appear to be more than %d minutes out of sync with the network, "
57 "this may lead to consensus failure. After you've confirmed your computer's clock, this message "
58 "should no longer appear when you restart your node. Without a restart, it should stop showing "
59 "automatically after you've connected to a sufficient number of new outbound peers, which may "
60 "take some time. You can inspect the `timeoffset` field of the `getpeerinfo` and `getnetworkinfo` "
61 "RPC methods to get more info."
62 ), Ticks<std::chrono::minutes>(WARN_THRESHOLD))};
63 LogWarning("%s\n", msg.original);
64 m_warnings.Set(node::Warning::CLOCK_OUT_OF_SYNC, msg);
65 return true;
66 }
67