-
#ifdef WIN32
#include <winsock2.h>
#else
#endif
#include "netbase.h"
-#include "util.h"
#include "net.h"
+#include "util.h"
extern int GetRandInt(int nMax);
uint8_t mac[5 * sizeof(uint32_t)]; /* mac */
};
-int nServersCount = 112;
+const int nServersCount = 147;
-std::string NtpServers[112] = {
+std::string NtpServers[147] = {
// Microsoft
"time.windows.com",
"time3.google.com",
"time4.google.com",
+ // Hurricane Electric
+ "clock.sjc.he.net",
+ "clock.nyc.he.net",
+
+ // SixXS
+ "ntp.sixxs.net",
+ "ntp.eu.sixxs.net",
+ "ntp.us.sixxs.net",
+ "ntp.ap.sixxs.net",
+
// Russian Federation
"ntp.karelia.pro",
"ntp.alpet.me",
"3.ru.pool.ntp.org",
// United States
+ "tock.cs.unlv.edu",
+ "timex.cs.columbia.edu",
+ "tick.cs.unlv.edu",
+ "sundial.columbia.edu",
+ "ntp-1.ece.cmu.edu",
+ "ntp-2.ece.cmu.edu",
+ "ntp1.cs.wisc.edu",
+ "ntp2.cs.wisc.edu",
+ "ntp3.cs.wisc.edu",
"ntp-01.caltech.edu",
"ntp-02.caltech.edu",
"ntp-03.caltech.edu",
// United Kingdom
"ntp2d.mcc.ac.uk",
"ntp2c.mcc.ac.uk",
+ "ntp2b.mcc.ac.uk",
"ntp.exnet.com",
"ntp.cis.strath.ac.uk",
"ntppub.le.ac.uk",
"2.uk.pool.ntp.org",
"3.uk.pool.ntp.org",
+ // Canada
+ "chime.utoronto.ca",
+ "tick.utoronto.ca",
+ "time.nrc.ca",
+ "timelord.uregina.ca",
+ "tock.utoronto.ca",
+ "www1.cmc.ec.gc.ca",
+ "www2.cmc.ec.gc.ca",
+ "0.ca.pool.ntp.org",
+ "1.ca.pool.ntp.org",
+ "2.ca.pool.ntp.org",
+ "3.ca.pool.ntp.org",
+
// Japan
"ntp.nict.jp",
"0.jp.pool.ntp.org",
"2.jp.pool.ntp.org",
"3.jp.pool.ntp.org",
- // ... To be continued
-};
-
-bool InitWithRandom(SOCKET &sockfd, socklen_t &servlen, struct sockaddr *pcliaddr) {
- int nAttempt = 0;
-
- while(nAttempt < 100) {
- sockfd = -1;
- nAttempt++;
-
- int nServerNum = GetRandInt(nServersCount);
-
- std::vector<CNetAddr> vIP;
- bool fRet = LookupHost(NtpServers[nServerNum].c_str(), vIP, 10, true);
- if (!fRet)
- continue;
-
- struct sockaddr_in servaddr;
- servaddr.sin_family = AF_INET;
- servaddr.sin_port = htons(123);
-
- bool found = false;
- for(unsigned int i = 0; i < vIP.size(); i++) {
- if ((found = vIP[i].GetInAddr(&servaddr.sin_addr))) {
- break;
- }
- }
-
- if (!found)
- continue;
-
- sockfd = socket(AF_INET, SOCK_DGRAM, 0);
+ // Australia
+ "ntp.cs.mu.oz.au",
+ "augean.eleceng.adelaide.edu.au",
+ "0.au.pool.ntp.org",
+ "1.au.pool.ntp.org",
+ "2.au.pool.ntp.org",
+ "3.au.pool.ntp.org",
- if (sockfd == INVALID_SOCKET)
- continue; // socket initialization error
+ // Slovenia
+ "time.ijs.si",
- if (connect(sockfd, (struct sockaddr *) &servaddr, sizeof(servaddr)) == -1 ) {
- continue; // "connection" error
- }
-
- *pcliaddr = *((struct sockaddr *) &servaddr);
- servlen = sizeof(servaddr);
- return true;
- }
+ // ???
+ "clepsydra.dec.com",
- return false;
-}
+ // ... To be continued
+};
bool InitWithHost(std::string &strHostName, SOCKET &sockfd, socklen_t &servlen, struct sockaddr *pcliaddr) {
sockfd = -1;
return true;
}
+bool InitWithRandom(SOCKET &sockfd, socklen_t &servlen, struct sockaddr *pcliaddr) {
+
+ for (int nAttempt = 0; nAttempt < nServersCount; nAttempt++) {
+ int nServerNum = GetRandInt(nServersCount);
+ if (InitWithHost(NtpServers[nServerNum], sockfd, servlen, pcliaddr)) {
+ return true;
+ }
+ }
+
+ return false;
+}
int64_t DoReq(SOCKET sockfd, socklen_t servlen, struct sockaddr cliaddr) {
#ifdef WIN32
}
recvfrom(sockfd, (char *) msg, len, 0, NULL, NULL);
-
- ntohl_fp(&msg->rec, &prt->rec);
ntohl_fp(&msg->xmt, &prt->xmt);
-
- time_t seconds_receive;
time_t seconds_transmit;
-
- Ntp2Unix(prt->rec.Ul_i.Xl_ui, seconds_receive);
Ntp2Unix(prt->xmt.Ul_i.Xl_ui, seconds_transmit);
delete msg;
delete prt;
- return (seconds_receive + seconds_transmit) / 2;
-}
-
-int64_t NtpGetTime() {
- struct sockaddr cliaddr;
-
- SOCKET sockfd;
- socklen_t servlen;
-
- if (!InitWithRandom(sockfd, servlen, &cliaddr))
- return -1;
-
- int64_t nTime = DoReq(sockfd, servlen, cliaddr);
-
- closesocket(sockfd);
-
- return nTime;
+ return seconds_transmit;
}
int64_t NtpGetTime(CNetAddr& ip) {
return nTime;
}
-void ThreadNtpSamples(void* parg)
-{
+// NTP server, which we unconditionally trust. This may be your own installation of ntpd somewhere, for example.
+// "localhost" means "trust no one"
+std::string strTrustedUpstream = "localhost";
+
+// Current offset
+int64_t nNtpOffset = INT64_MAX;
+
+int64_t GetNtpOffset() {
+ return nNtpOffset;
+}
+
+void ThreadNtpSamples(void* parg) {
+
+ // Maximum offset is 2 hours.
+ const int64_t nMaxOffset = 7200;
+
printf("ThreadNtpSamples started\n");
vnThreadsRunning[THREAD_NTP]++;
// Make this thread recognisable as time synchronization thread
RenameThread("novacoin-ntp-samples");
+ CMedianFilter<int64_t> vTimeOffsets(200,0);
+
while (!fShutdown) {
- CNetAddr ip;
- int64_t nTime = NtpGetTime(ip);
+ if (strTrustedUpstream != "localhost") {
+ // Trying to get new offset sample from trusted NTP server.
+ int64_t nClockOffset = NtpGetTime(strTrustedUpstream) - GetTime();
+
+ if (abs64(nClockOffset) < nMaxOffset) {
+ // Everything seems right, remember new trusted offset.
+ nNtpOffset = nClockOffset;
+ }
+ else {
+ // Something went wrong, disable trusted offset sampling.
+ nNtpOffset = INT64_MAX;
+ strTrustedUpstream = "localhost";
- if (nTime > 0 && nTime != 2085978496) { // Skip the deliberately wrong timestamps
- AddTimeData(ip, nTime);
+ int nSleepMinutes = 1 + GetRandInt(9); // Sleep for 1-10 minutes.
+ for (int i = 0; i < nSleepMinutes * 60 && !fShutdown; i++)
+ Sleep(1000);
+
+ continue;
+ }
}
else {
- Sleep(600000); // In case of failure wait 600 seconds and then try again
- continue;
+ // Now, trying to get 2-4 samples from random NTP servers.
+ int nSamplesCount = 2 + GetRandInt(2);
+
+ for (int i = 0; i < nSamplesCount; i++) {
+ CNetAddr ip;
+ int64_t nClockOffset = NtpGetTime(ip) - GetTime();
+
+ if (abs64(nClockOffset) < nMaxOffset) { // Skip the deliberately wrong timestamps
+ vTimeOffsets.input(nClockOffset);
+ }
+ }
+
+ if (vTimeOffsets.size() > 2) {
+ nNtpOffset = vTimeOffsets.median();
+ }
+ else {
+ // Not enough offsets yet, try again later.
+ nNtpOffset = INT64_MAX;
+ int nSleepMinutes = 1 + GetRandInt(4); // Sleep for 1-5 minutes.
+ for (int i = 0; i < nSleepMinutes * 60 && !fShutdown; i++)
+ Sleep(1000);
+ continue;
+ }
}
- Sleep(43200000); // Sleep for 12 hours
+ printf("nNtpOffset = %+" PRId64 " (%+" PRId64 " minutes)\n", nNtpOffset, nNtpOffset/60);
+
+ int nSleepHours = 1 + GetRandInt(5); // Sleep for 1-6 hours.
+ for (int i = 0; i < nSleepHours * 3600 && !fShutdown; i++)
+ Sleep(1000);
}
vnThreadsRunning[THREAD_NTP]--;