4 #include <sys/socket.h>
6 #include <netinet/in.h>
14 #include "interface.h"
16 extern int GetRandInt(int nMax);
19 * NTP uses two fixed point formats. The first (l_fp) is the "long"
20 * format and is 64 bits long with the decimal between bits 31 and 32.
21 * This is used for time stamps in the NTP packet header (in network
22 * byte order) and for internal computations of offsets (in local host
23 * byte order). We use the same structure for both signed and unsigned
24 * values, which is a big hack but saves rewriting all the operators
25 * twice. Just to confuse this, we also sometimes just carry the
26 * fractional part in calculations, in both signed and unsigned forms.
27 * Anyway, an l_fp looks like:
30 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
31 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
33 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
35 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
36 * REF http://www.eecis.udel.edu/~mills/database/rfc/rfc2030.txt
52 inline void Ntp2Unix(const uint32_t &n, time_t &u) {
53 // Ntp's time scale starts in 1900, Unix in 1970.
55 u = n - 0x83aa7e80; // 2208988800 1970 - 1900 in seconds
58 inline void ntohl_fp(l_fp *n, l_fp *h) {
59 (h)->Ul_i.Xl_ui = ntohl((n)->Ul_i.Xl_ui);
60 (h)->Ul_f.Xl_uf = ntohl((n)->Ul_f.Xl_uf);
64 uint8_t li_vn_mode; /* leap indicator, version and mode */
65 uint8_t stratum; /* peer stratum */
66 uint8_t ppoll; /* peer poll interval */
67 int8_t precision; /* peer clock precision */
68 uint32_t rootdelay; /* distance to primary clock */
69 uint32_t rootdispersion; /* clock dispersion */
70 uint32_t refid; /* reference clock ID */
71 l_fp ref; /* time peer clock was last updated */
72 l_fp org; /* originate time stamp */
73 l_fp rec; /* receive time stamp */
74 l_fp xmt; /* transmit time stamp */
76 uint32_t exten[1]; /* misused */
77 uint8_t mac[5 * sizeof(uint32_t)]; /* mac */
80 const int nServersCount = 154;
82 std::string NtpServers[nServersCount] = {
121 "ntp1.niiftri.irkutsk.ru",
122 "ntp2.niiftri.irkutsk.ru",
134 "timex.cs.columbia.edu",
136 "sundial.columbia.edu",
144 "ntp-01.caltech.edu",
145 "ntp-02.caltech.edu",
146 "ntp-03.caltech.edu",
147 "ntp-04.caltech.edu",
148 "nist0-pa.ustiming.org",
149 "nist1-pa.ustiming.org",
150 "nist2-pa.ustiming.org",
157 "nist1-macon.macon.ga.us",
158 "nist.netservicesgroup.com",
160 "time-a.timefreq.bldrdoc.gov",
161 "time-b.timefreq.bldrdoc.gov",
162 "time-c.timefreq.bldrdoc.gov",
163 "utcnist.colorado.edu",
164 "utcnist2.colorado.edu",
165 "nist1-lv.ustiming.org",
178 "bonehed.lcs.mit.edu",
179 "ntp-s1.cise.ufl.edu",
182 "ntp1.meraka.csir.co.za",
186 "ntp1.neology.co.za",
187 "ntp2.neology.co.za",
188 "tick.meraka.csir.co.za",
189 "tock.meraka.csir.co.za",
191 "ntp1.meraka.csir.co.za",
192 "ntp2.meraka.csir.co.za",
224 "ntp.cis.strath.ac.uk",
235 "timelord.uregina.ca",
251 "augean.eleceng.adelaide.edu.au",
269 // ... To be continued
272 bool InitWithHost(const std::string &strHostName, SOCKET &sockfd, socklen_t &servlen, struct sockaddr *pcliaddr) {
274 sockfd = INVALID_SOCKET;
276 std::vector<CNetAddr> vIP;
277 bool fRet = LookupHost(strHostName.c_str(), vIP, 10, true);
282 struct sockaddr_in servaddr;
283 servaddr.sin_family = AF_INET;
284 servaddr.sin_port = htons(123);
287 for(unsigned int i = 0; i < vIP.size(); i++) {
288 if ((found = vIP[i].GetInAddr(&servaddr.sin_addr)) != false) {
297 sockfd = socket(AF_INET, SOCK_DGRAM, 0);
299 if (sockfd == INVALID_SOCKET)
300 return false; // socket initialization error
302 if (connect(sockfd, (struct sockaddr *) &servaddr, sizeof(servaddr)) == -1 ) {
303 return false; // "connection" error
307 *pcliaddr = *((struct sockaddr *) &servaddr);
308 servlen = sizeof(servaddr);
313 bool InitWithRandom(SOCKET &sockfd, socklen_t &servlen, struct sockaddr *pcliaddr) {
315 for (int nAttempt = 0; nAttempt < nServersCount; nAttempt++) {
316 int nServerNum = GetRandInt(nServersCount);
317 if (InitWithHost(NtpServers[nServerNum], sockfd, servlen, pcliaddr)) {
325 int64_t DoReq(SOCKET sockfd, socklen_t servlen, struct sockaddr cliaddr) {
330 if (ioctlsocket(sockfd, FIONBIO, &nOne) == SOCKET_ERROR) {
331 printf("ConnectSocket() : ioctlsocket non-blocking setting failed, error %d\n", WSAGetLastError());
333 if (fcntl(sockfd, F_SETFL, O_NONBLOCK) == SOCKET_ERROR) {
334 printf("ConnectSocket() : fcntl non-blocking setting failed, error %d\n", errno);
339 struct timeval timeout = {10, 0};
340 struct pkt *msg = new pkt;
341 struct pkt *prt = new pkt;
342 time_t seconds_transmit;
350 msg->rootdispersion=0;
352 msg->ref.Ul_i.Xl_i=0;
353 msg->ref.Ul_f.Xl_f=0;
354 msg->org.Ul_i.Xl_i=0;
355 msg->org.Ul_f.Xl_f=0;
356 msg->rec.Ul_i.Xl_i=0;
357 msg->rec.Ul_f.Xl_f=0;
358 msg->xmt.Ul_i.Xl_i=0;
359 msg->xmt.Ul_f.Xl_f=0;
361 int retcode = sendto(sockfd, (char *) msg, len, 0, &cliaddr, servlen);
363 printf("sendto() failed: %d\n", retcode);
364 seconds_transmit = -3;
370 FD_SET(sockfd, &fdset);
372 retcode = select(sockfd + 1, &fdset, NULL, NULL, &timeout);
374 printf("recvfrom() error\n");
375 seconds_transmit = -4;
379 recvfrom(sockfd, (char *) msg, len, 0, NULL, NULL);
380 ntohl_fp(&msg->xmt, &prt->xmt);
381 Ntp2Unix(prt->xmt.Ul_i.Xl_ui, seconds_transmit);
388 return seconds_transmit;
391 int64_t NtpGetTime(CNetAddr& ip) {
392 struct sockaddr cliaddr;
397 if (!InitWithRandom(sockfd, servlen, &cliaddr))
400 ip = CNetAddr(((sockaddr_in *)&cliaddr)->sin_addr);
401 int64_t nTime = DoReq(sockfd, servlen, cliaddr);
408 int64_t NtpGetTime(const std::string &strHostName)
410 struct sockaddr cliaddr;
415 if (!InitWithHost(strHostName, sockfd, servlen, &cliaddr))
418 int64_t nTime = DoReq(sockfd, servlen, cliaddr);
425 // NTP server, which we unconditionally trust. This may be your own installation of ntpd somewhere, for example.
426 // "localhost" means "trust no one"
427 std::string strTrustedUpstream = "localhost";
430 int64_t nNtpOffset = INT64_MAX;
432 int64_t GetNtpOffset() {
436 void ThreadNtpSamples(void* parg) {
437 const int64_t nMaxOffset = nOneDay; // Not a real limit, just sanity threshold.
439 printf("Trying to find NTP server at localhost...\n");
441 std::string strLocalHost = "127.0.0.1";
442 if (NtpGetTime(strLocalHost) == GetTime()) {
443 printf("There is NTP server active at localhost, we don't need NTP thread.\n");
449 printf("ThreadNtpSamples started\n");
450 vnThreadsRunning[THREAD_NTP]++;
452 // Make this thread recognisable as time synchronization thread
453 RenameThread("novacoin-ntp-samples");
455 CMedianFilter<int64_t> vTimeOffsets(200,0);
458 if (strTrustedUpstream != "localhost") {
459 // Trying to get new offset sample from trusted NTP server.
460 int64_t nClockOffset = NtpGetTime(strTrustedUpstream) - GetTime();
462 if (abs(nClockOffset) < nMaxOffset) {
463 // Everything seems right, remember new trusted offset.
464 printf("ThreadNtpSamples: new offset sample from %s, offset=%" PRId64 ".\n", strTrustedUpstream.c_str(), nClockOffset);
465 nNtpOffset = nClockOffset;
468 // Something went wrong, disable trusted offset sampling.
469 nNtpOffset = INT64_MAX;
470 strTrustedUpstream = "localhost";
472 int nSleepMinutes = 1 + GetRandInt(9); // Sleep for 1-10 minutes.
473 for (int i = 0; i < nSleepMinutes * 60 && !fShutdown; i++)
480 // Now, trying to get 2-4 samples from random NTP servers.
481 int nSamplesCount = 2 + GetRandInt(2);
483 for (int i = 0; i < nSamplesCount; i++) {
485 int64_t nClockOffset = NtpGetTime(ip) - GetTime();
487 if (abs(nClockOffset) < nMaxOffset) { // Skip the deliberately wrong timestamps
488 printf("ThreadNtpSamples: new offset sample from %s, offset=%" PRId64 ".\n", ip.ToString().c_str(), nClockOffset);
489 vTimeOffsets.input(nClockOffset);
493 if (vTimeOffsets.size() > 1) {
494 nNtpOffset = vTimeOffsets.median();
497 // Not enough offsets yet, try to collect additional samples later.
498 nNtpOffset = INT64_MAX;
499 int nSleepMinutes = 1 + GetRandInt(4); // Sleep for 1-5 minutes.
500 for (int i = 0; i < nSleepMinutes * 60 && !fShutdown; i++)
506 if (GetNodesOffset() == INT_MAX && abs(nNtpOffset) > 40 * 60)
508 // If there is not enough node offsets data and NTP time offset is greater than 40 minutes then give a warning.
509 std::string strMessage = _("Warning: Please check that your computer's date and time are correct! If your clock is wrong NovaCoin will not work properly.");
510 strMiscWarning = strMessage;
511 printf("*** %s\n", strMessage.c_str());
512 uiInterface.ThreadSafeMessageBox(strMessage+" ", std::string("NovaCoin"), CClientUIInterface::OK | CClientUIInterface::ICON_EXCLAMATION);
515 printf("nNtpOffset = %+" PRId64 " (%+" PRId64 " minutes)\n", nNtpOffset, nNtpOffset/60);
517 int nSleepHours = 1 + GetRandInt(5); // Sleep for 1-6 hours.
518 for (int i = 0; i < nSleepHours * 3600 && !fShutdown; i++)
522 vnThreadsRunning[THREAD_NTP]--;
523 printf("ThreadNtpSamples exited\n");