4 #include <sys/socket.h>
6 #include <netinet/in.h>
16 #include "interface.h"
18 extern int GetRandInt(int nMax);
21 * NTP uses two fixed point formats. The first (l_fp) is the "long"
22 * format and is 64 bits long with the decimal between bits 31 and 32.
23 * This is used for time stamps in the NTP packet header (in network
24 * byte order) and for internal computations of offsets (in local host
25 * byte order). We use the same structure for both signed and unsigned
26 * values, which is a big hack but saves rewriting all the operators
27 * twice. Just to confuse this, we also sometimes just carry the
28 * fractional part in calculations, in both signed and unsigned forms.
29 * Anyway, an l_fp looks like:
32 * 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
33 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
35 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
37 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
38 * REF http://www.eecis.udel.edu/~mills/database/rfc/rfc2030.txt
54 inline void Ntp2Unix(const uint32_t &n, time_t &u) {
55 // Ntp's time scale starts in 1900, Unix in 1970.
57 u = n - 0x83aa7e80; // 2208988800 1970 - 1900 in seconds
60 inline void ntohl_fp(l_fp *n, l_fp *h) {
61 (h)->Ul_i.Xl_ui = ntohl((n)->Ul_i.Xl_ui);
62 (h)->Ul_f.Xl_uf = ntohl((n)->Ul_f.Xl_uf);
66 uint8_t li_vn_mode; /* leap indicator, version and mode */
67 uint8_t stratum; /* peer stratum */
68 uint8_t ppoll; /* peer poll interval */
69 int8_t precision; /* peer clock precision */
70 uint32_t rootdelay; /* distance to primary clock */
71 uint32_t rootdispersion; /* clock dispersion */
72 uint32_t refid; /* reference clock ID */
73 l_fp ref; /* time peer clock was last updated */
74 l_fp org; /* originate time stamp */
75 l_fp rec; /* receive time stamp */
76 l_fp xmt; /* transmit time stamp */
78 uint32_t exten[1]; /* misused */
79 uint8_t mac[5 * sizeof(uint32_t)]; /* mac */
82 const int nServersCount = 154;
84 std::string NtpServers[nServersCount] = {
101 // Russian Federation
123 "ntp1.niiftri.irkutsk.ru",
124 "ntp2.niiftri.irkutsk.ru",
136 "timex.cs.columbia.edu",
138 "sundial.columbia.edu",
146 "ntp-01.caltech.edu",
147 "ntp-02.caltech.edu",
148 "ntp-03.caltech.edu",
149 "ntp-04.caltech.edu",
150 "nist0-pa.ustiming.org",
151 "nist1-pa.ustiming.org",
152 "nist2-pa.ustiming.org",
159 "nist1-macon.macon.ga.us",
160 "nist.netservicesgroup.com",
162 "time-a.timefreq.bldrdoc.gov",
163 "time-b.timefreq.bldrdoc.gov",
164 "time-c.timefreq.bldrdoc.gov",
165 "utcnist.colorado.edu",
166 "utcnist2.colorado.edu",
167 "nist1-lv.ustiming.org",
180 "bonehed.lcs.mit.edu",
181 "ntp-s1.cise.ufl.edu",
184 "ntp1.meraka.csir.co.za",
188 "ntp1.neology.co.za",
189 "ntp2.neology.co.za",
190 "tick.meraka.csir.co.za",
191 "tock.meraka.csir.co.za",
193 "ntp1.meraka.csir.co.za",
194 "ntp2.meraka.csir.co.za",
226 "ntp.cis.strath.ac.uk",
237 "timelord.uregina.ca",
253 "augean.eleceng.adelaide.edu.au",
271 // ... To be continued
274 bool InitWithHost(const std::string &strHostName, SOCKET &sockfd, socklen_t &servlen, struct sockaddr *pcliaddr) {
276 sockfd = INVALID_SOCKET;
278 std::vector<CNetAddr> vIP;
279 bool fRet = LookupHost(strHostName.c_str(), vIP, 10, true);
284 struct sockaddr_in servaddr;
285 servaddr.sin_family = AF_INET;
286 servaddr.sin_port = htons(123);
289 for(unsigned int i = 0; i < vIP.size(); i++) {
290 if ((found = vIP[i].GetInAddr(&servaddr.sin_addr)) != false) {
299 sockfd = socket(AF_INET, SOCK_DGRAM, 0);
301 if (sockfd == INVALID_SOCKET)
302 return false; // socket initialization error
304 if (connect(sockfd, (struct sockaddr *) &servaddr, sizeof(servaddr)) == -1 ) {
305 return false; // "connection" error
309 *pcliaddr = *((struct sockaddr *) &servaddr);
310 servlen = sizeof(servaddr);
315 bool InitWithRandom(SOCKET &sockfd, socklen_t &servlen, struct sockaddr *pcliaddr) {
317 for (int nAttempt = 0; nAttempt < nServersCount; nAttempt++) {
318 int nServerNum = GetRandInt(nServersCount);
319 if (InitWithHost(NtpServers[nServerNum], sockfd, servlen, pcliaddr)) {
327 int64_t DoReq(SOCKET sockfd, socklen_t servlen, struct sockaddr cliaddr) {
332 if (ioctlsocket(sockfd, FIONBIO, &nOne) == SOCKET_ERROR) {
333 printf("ConnectSocket() : ioctlsocket non-blocking setting failed, error %d\n", WSAGetLastError());
335 if (fcntl(sockfd, F_SETFL, O_NONBLOCK) == SOCKET_ERROR) {
336 printf("ConnectSocket() : fcntl non-blocking setting failed, error %d\n", errno);
341 struct timeval timeout = {10, 0};
342 struct pkt *msg = new pkt;
343 struct pkt *prt = new pkt;
344 time_t seconds_transmit;
352 msg->rootdispersion=0;
354 msg->ref.Ul_i.Xl_i=0;
355 msg->ref.Ul_f.Xl_f=0;
356 msg->org.Ul_i.Xl_i=0;
357 msg->org.Ul_f.Xl_f=0;
358 msg->rec.Ul_i.Xl_i=0;
359 msg->rec.Ul_f.Xl_f=0;
360 msg->xmt.Ul_i.Xl_i=0;
361 msg->xmt.Ul_f.Xl_f=0;
363 int retcode = sendto(sockfd, (char *) msg, len, 0, &cliaddr, servlen);
365 printf("sendto() failed: %d\n", retcode);
366 seconds_transmit = -3;
372 FD_SET(sockfd, &fdset);
374 retcode = select(sockfd + 1, &fdset, NULL, NULL, &timeout);
376 printf("recvfrom() error\n");
377 seconds_transmit = -4;
381 recvfrom(sockfd, (char *) msg, len, 0, NULL, NULL);
382 ntohl_fp(&msg->xmt, &prt->xmt);
383 Ntp2Unix(prt->xmt.Ul_i.Xl_ui, seconds_transmit);
390 return seconds_transmit;
393 int64_t NtpGetTime(CNetAddr& ip) {
394 struct sockaddr cliaddr;
399 if (!InitWithRandom(sockfd, servlen, &cliaddr))
402 ip = CNetAddr(((sockaddr_in *)&cliaddr)->sin_addr);
403 int64_t nTime = DoReq(sockfd, servlen, cliaddr);
410 int64_t NtpGetTime(const std::string &strHostName)
412 struct sockaddr cliaddr;
417 if (!InitWithHost(strHostName, sockfd, servlen, &cliaddr))
420 int64_t nTime = DoReq(sockfd, servlen, cliaddr);
427 // NTP server, which we unconditionally trust. This may be your own installation of ntpd somewhere, for example.
428 // "localhost" means "trust no one"
429 std::string strTrustedUpstream = "localhost";
432 int64_t nNtpOffset = INT64_MAX;
434 int64_t GetNtpOffset() {
438 void ThreadNtpSamples(void* parg) {
439 const int64_t nMaxOffset = nOneDay; // Not a real limit, just sanity threshold.
441 printf("Trying to find NTP server at localhost...\n");
443 std::string strLocalHost = "127.0.0.1";
444 if (NtpGetTime(strLocalHost) == GetTime()) {
445 printf("There is NTP server active at localhost, we don't need NTP thread.\n");
451 printf("ThreadNtpSamples started\n");
452 vnThreadsRunning[THREAD_NTP]++;
454 // Make this thread recognisable as time synchronization thread
455 RenameThread("novacoin-ntp-samples");
457 CMedianFilter<int64_t> vTimeOffsets(200,0);
460 if (strTrustedUpstream != "localhost") {
461 // Trying to get new offset sample from trusted NTP server.
462 int64_t nClockOffset = NtpGetTime(strTrustedUpstream) - GetTime();
464 if (abs(nClockOffset) < nMaxOffset) {
465 // Everything seems right, remember new trusted offset.
466 printf("ThreadNtpSamples: new offset sample from %s, offset=%" PRId64 ".\n", strTrustedUpstream.c_str(), nClockOffset);
467 nNtpOffset = nClockOffset;
470 // Something went wrong, disable trusted offset sampling.
471 nNtpOffset = INT64_MAX;
472 strTrustedUpstream = "localhost";
474 int nSleepMinutes = 1 + GetRandInt(9); // Sleep for 1-10 minutes.
475 for (int i = 0; i < nSleepMinutes * 60 && !fShutdown; i++)
482 // Now, trying to get 2-4 samples from random NTP servers.
483 int nSamplesCount = 2 + GetRandInt(2);
485 for (int i = 0; i < nSamplesCount; i++) {
487 int64_t nClockOffset = NtpGetTime(ip) - GetTime();
489 if (abs(nClockOffset) < nMaxOffset) { // Skip the deliberately wrong timestamps
490 printf("ThreadNtpSamples: new offset sample from %s, offset=%" PRId64 ".\n", ip.ToString().c_str(), nClockOffset);
491 vTimeOffsets.input(nClockOffset);
495 if (vTimeOffsets.size() > 1) {
496 nNtpOffset = vTimeOffsets.median();
499 // Not enough offsets yet, try to collect additional samples later.
500 nNtpOffset = INT64_MAX;
501 int nSleepMinutes = 1 + GetRandInt(4); // Sleep for 1-5 minutes.
502 for (int i = 0; i < nSleepMinutes * 60 && !fShutdown; i++)
508 if (GetNodesOffset() == INT_MAX && abs(nNtpOffset) > 40 * 60)
510 // If there is not enough node offsets data and NTP time offset is greater than 40 minutes then give a warning.
511 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.");
512 strMiscWarning = strMessage;
513 printf("*** %s\n", strMessage.c_str());
514 uiInterface.ThreadSafeMessageBox(strMessage+" ", std::string("NovaCoin"), CClientUIInterface::OK | CClientUIInterface::ICON_EXCLAMATION);
517 printf("nNtpOffset = %+" PRId64 " (%+" PRId64 " minutes)\n", nNtpOffset, nNtpOffset/60);
519 int nSleepHours = 1 + GetRandInt(5); // Sleep for 1-6 hours.
520 for (int i = 0; i < nSleepHours * 3600 && !fShutdown; i++)
524 vnThreadsRunning[THREAD_NTP]--;
525 printf("ThreadNtpSamples exited\n");