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-rw-r--r--toys/pending/sntp.c269
1 files changed, 0 insertions, 269 deletions
diff --git a/toys/pending/sntp.c b/toys/pending/sntp.c
deleted file mode 100644
index f1415332..00000000
--- a/toys/pending/sntp.c
+++ /dev/null
@@ -1,269 +0,0 @@
-/* sntp.c - sntp client and server
- *
- * Copyright 2019 Rob Landley <rob@landley.net>
- *
- * See https://www.ietf.org/rfc/rfc4330.txt
-
- modes: oneshot display, oneshot set, persist, serve, multi
-
-USE_SNTP(NEWTOY(sntp, "m:Sp:asdDqr#<4>17=10[!as]", TOYFLAG_USR|TOYFLAG_BIN))
-
-config SNTP
- bool "sntp"
- default n
- help
- usage: sntp [-saSdDqm] [-r SHIFT] [-m ADDRESS] [-p PORT] [SERVER]
-
- Simple Network Time Protocol client. Query SERVER and display time.
-
- -p Use PORT (default 123)
- -s Set system clock suddenly
- -a Adjust system clock gradually
- -S Serve time instead of querying (bind to SERVER address if specified)
- -m Wait for updates from multicast ADDRESS (RFC 4330 says use 224.0.1.1)
- -d Daemonize (run in background re-querying )
- -D Daemonize but stay in foreground: re-query time every 1000 seconds
- -r Retry shift (every 1<<SHIFT seconds)
- -q Quiet (don't display time)
-*/
-
-#define FOR_sntp
-#include "toys.h"
-
-GLOBALS(
- long r;
- char *p, *m;
-)
-
-// Seconds from 1900 to 1970, including appropriate leap days
-#define SEVENTIES 2208988800L
-
-union socksaddr {
- struct sockaddr_in in;
- struct sockaddr_in6 in6;
-};
-
-// timeout in milliseconds
-int xrecvwait(int fd, char *buf, int len, union socksaddr *sa, int timeout)
-{
- socklen_t sl = sizeof(*sa);
-
- if (timeout >= 0) {
- struct pollfd pfd;
-
- pfd.fd = fd;
- pfd.events = POLLIN;
- if (!xpoll(&pfd, 1, timeout)) return 0;
- }
-
- len = recvfrom(fd, buf, len, 0, (void *)sa, &sl);
- if (len<0) perror_exit("recvfrom");
-
- return len;
-}
-
-// Adjust timespec by nanosecond offset
-static void nanomove(struct timespec *ts, long long offset)
-{
- long long nano = ts->tv_nsec + offset, secs = nano/1000000000;
-
- ts->tv_sec += secs;
- nano %= 1000000000;
- if (nano<0) {
- ts->tv_sec--;
- nano += 1000000000;
- }
- ts->tv_nsec = nano;
-}
-
-// Get time and return ntptime (saving timespec in pointer if not null)
-// NTP time is high 32 bits = seconds since 1970 (blame RFC 868), low 32 bits
-// fraction of a second.
-// diff is how far off we think our clock is from reality (in nanoseconds)
-static unsigned long long lunchtime(struct timespec *television, long long diff)
-{
- struct timespec tv;
-
- clock_gettime(CLOCK_REALTIME, &tv);
- if (diff) nanomove(&tv, diff);
-
- if (television) *television = tv;
-
- // Unix time is 1970 but RFCs 868 and 958 said 1900 so add seconds 1900->1970
- // If they'd done a 34/30 bit split the Y2036 problem would be centuries
- // from now and still give us nanosecond accuracy, but no...
- return ((tv.tv_sec+SEVENTIES)<<32)+(((long long)tv.tv_nsec)<<32)/1000000000;
-}
-
-// convert ntptime back to struct timespec.
-static void doublyso(unsigned long long now, struct timespec *tv)
-{
- // Y2036 fixup: if time wrapped, it's in the future
- tv->tv_sec = (now>>32) + (1LL<<32)*!(now&(1LL<<63));
- tv->tv_sec -= SEVENTIES; // Force signed math for Y2038 fixup
- tv->tv_nsec = ((now&0xFFFFFFFF)*1000000000)>>32;
-}
-
-// return difference between two timespecs in nanosecs
-static long long nanodiff(struct timespec *old, struct timespec *new)
-{
- return (new->tv_sec - old->tv_sec)*1000000000LL+(new->tv_nsec - old->tv_nsec);
-}
-
-void sntp_main(void)
-{
- struct timespec tv, tv2;
- unsigned long long *pktime = (void *)toybuf, now, then, before = before;
- long long diff = 0;
- struct addrinfo *ai;
- union socksaddr sa;
- int fd, tries = 0;
-
- if (!(FLAG(S)||FLAG(m)) && !*toys.optargs)
- error_exit("Need -Sm or SERVER address");
-
- // Lookup address and open server or client UDP socket
- if (!TT.p || !*TT.p) TT.p = "123";
- ai = xgetaddrinfo(*toys.optargs, TT.p, AF_UNSPEC, SOCK_DGRAM, IPPROTO_UDP,
- AI_PASSIVE*!*toys.optargs);
-
- if (FLAG(d) && daemon(0, 0)) perror_exit("daemonize");
-
- // Act as server if necessary
- if (FLAG(S)|FLAG(m)) {
- fd = xbind(ai);
- if (TT.m) {
- struct ip_mreq group;
-
- // subscribe to multicast group
- memset(&group, 0, sizeof(group));
- group.imr_multiaddr.s_addr = inet_addr(TT.m);
- xsetsockopt(fd, IPPROTO_IP, IP_ADD_MEMBERSHIP, &group, sizeof(group));
- }
- } else fd = xsocket(ai->ai_family, SOCK_DGRAM, IPPROTO_UDP);
-
- // -Sm = loop waiting for input
- // -Dd = loop polling time and waiting until next poll period
- // Otherwise poll up to 3 times to get 2 responses, then exit
-
- // loop sending/receiving packets
- for (;;) {
- now = millitime();
-
- // Figure out if we're in server and multicast modes don't poll
- if (FLAG(m) || FLAG(S)) then = -1;
-
- // daemon and oneshot modes send a packet each time through outer loop
- else {
- then = now + 3000;
- if (FLAG(d) || FLAG(D)) then = now + (1<<TT.r)*1000;
-
- // Send NTP query packet
- memset(toybuf, 0, 48);
- *toybuf = 0xe3; // li = 3 (unsynchronized), version = 4, mode = 3 (client)
- toybuf[2] = 8; // poll frequency 1<<8 = 256 seconds
- pktime[5] = SWAP_BE64(before = lunchtime(&tv, diff));
- xsendto(fd, toybuf, 48, ai->ai_addr);
- }
-
- // Loop receiving packets until it's time to send the next one.
- for (;;) {
- int strike;
-
- // Wait to receive a packet
-
- if (then>0 && then<(now = millitime())) break;;
- strike = xrecvwait(fd, toybuf, sizeof(toybuf), &sa, then-now);
- if (strike<1) {
- if (!(FLAG(S)||FLAG(m)||FLAG(D)||FLAG(d)) && ++tries == 3)
- error_exit("no reply from %s", *toys.optargs);
- break;
- }
- if (strike<48) continue;
-
- // Validate packet
- if (!FLAG(S) || FLAG(m)) {
- char buf[128];
- int mode = 7&*toybuf;
-
- // Is source address what we expect?
- xstrncpy(buf, ntop(ai->ai_addr), 128);
- strike = strcmp(buf, ntop((void *)&sa));
- // Does this reply's originate timestamp match the packet we sent?
- if (!FLAG(S) && !FLAG(m) && before != SWAP_BE64(pktime[3])) continue;
- // Ignore packets from wrong address or with wrong mode
- if (strike && !FLAG(S)) continue;
- if (!((FLAG(m) && mode==5) || (FLAG(S) && mode==3) ||
- (!FLAG(m) && !FLAG(S) && mode==4))) continue;
- }
-
- // If received a -S request packet, send server packet
- if (strike) {
- char *buf = toybuf+48;
-
- *buf = 0x24; // LI 0 VN 4 mode 4.
- buf[1] = 3; // stratum 3
- buf[2] = 10; // recommended retry every 1<<10=1024 seconds
- buf[3] = 250; // precision -6, minimum allowed
- strcpy(buf+12, "LOCL");
- pktime[6+3] = pktime[5]; // send back reference time they sent us
- // everything else is current time
- pktime[6+2] = pktime[6+4] = pktime[6+5] = SWAP_BE64(lunchtime(0, 0));
- xsendto(fd, buf, 48, (void *)&sa);
-
- // Got a time packet from a recognized server
- } else {
- int unset = !diff;
-
- // First packet: figure out how far off our clock is from what server
- // said and try again. Don't set clock, just record offset to use
- // generating second reuest. (We know this time is in the past
- // because transmission took time, but it's a start. And if time is
- // miraculously exact, don't loop.)
-
- lunchtime(&tv2, diff);
- diff = nanodiff(&tv, &tv2);
- if (unset && diff) break;
-
- // Second packet: determine midpoint of packet transit time according
- // to local clock, assuming each direction took same time so midpoint
- // is time server reported. The first television was the adjusted time
- // we sent the packet at, tv2 is what server replied, so now diff
- // is round trip time.
-
- // What time did the server say and how far off are we?
- nanomove(&tv, diff/2);
- doublyso(SWAP_BE64(pktime[5]), &tv2);
- diff = nanodiff(&tv, &tv2);
-
- if (FLAG(s)) {
- // Do read/adjust/set to lose as little time as possible.
- clock_gettime(CLOCK_REALTIME, &tv2);
- nanomove(&tv2, diff);
- if (clock_settime(CLOCK_REALTIME, &tv2))
- perror_exit("clock_settime");
- } else if (FLAG(a)) {
- struct timeval why;
-
- // call adjtime() to move the clock gradually, copying nanoseconds
- // into gratuitous microseconds structure for sad historical reasons
- memset(&tv2, 0, sizeof(tv2));
- nanomove(&tv2, diff);
- why.tv_sec = tv2.tv_sec;
- why.tv_usec = tv2.tv_nsec/1000;
- if (adjtime(&why, 0)) perror_exit("adjtime");
- }
-
- // Display the time and offset
- if (!FLAG(q)) {
- format_iso_time(toybuf, sizeof(toybuf)-1, &tv2);
- printf("%s offset %c%lld.%09lld secs\n", toybuf, (diff<0) ? '-' : '+',
- llabs(diff/1000000000), llabs(diff%1000000000));
- }
-
- // If we're not in daemon mode, we're done. (Can't get here for -S.)
- if (!FLAG(d) && !FLAG(D)) return;
- }
- }
- }
-}
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