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authorLaurent Bercot <ska-skaware@skarnet.org>2014-12-15 23:08:59 +0000
committerLaurent Bercot <ska-skaware@skarnet.org>2014-12-15 23:08:59 +0000
commite0fc82203d677a6f1e808e9a1a46176c109d89be (patch)
treee9609209b755e3f7a8480aea86601ffe9d4ca540 /src/clock/s6-taiclock.c
downloads6-networking-e0fc82203d677a6f1e808e9a1a46176c109d89be.tar.xz
Initial commit
Diffstat (limited to 'src/clock/s6-taiclock.c')
-rw-r--r--src/clock/s6-taiclock.c182
1 files changed, 182 insertions, 0 deletions
diff --git a/src/clock/s6-taiclock.c b/src/clock/s6-taiclock.c
new file mode 100644
index 0000000..99150b5
--- /dev/null
+++ b/src/clock/s6-taiclock.c
@@ -0,0 +1,182 @@
+/* ISC license. */
+
+#include <sys/types.h>
+#include <unistd.h>
+#include <errno.h>
+#include <skalibs/error.h>
+#include <skalibs/uint16.h>
+#include <skalibs/uint32.h>
+#include <skalibs/uint.h>
+#include <skalibs/sgetopt.h>
+#include <skalibs/allreadwrite.h>
+#include <skalibs/bytestr.h>
+#include <skalibs/strerr2.h>
+#include <skalibs/tai.h>
+#include <skalibs/djbtime.h>
+#include <skalibs/iopause.h>
+#include <skalibs/allreadwrite.h>
+#include <skalibs/socket.h>
+#include <skalibs/ip46.h>
+#include <skalibs/random.h>
+
+#define USAGE "s6-taiclock [ -f ] [ -v verbosity ] [ -r roundtrips ] [ -t triptimeout ] [ -h throttle ] [ -T totaltimeout ] [ -e errmax ] [ -p port ] ipaddress"
+#define dieusage() strerr_dieusage(100, USAGE)
+
+static unsigned int verbosity = 1 ;
+
+#define N 28
+
+int tain_exchange (int s, ip46_t const *ip, uint16 port, tain_t *serversays, tain_t const *deadline)
+{
+ char query[N] = "ctai" ;
+ char answer[N] ;
+ ip46_t dummyip ;
+ int r ;
+ uint16 dummyport ;
+ tain_pack(query+4, &STAMP) ;
+ if (badrandom_string(query+20, N-20) < N-20) return 0 ; /* cookie */
+ r = socket_sendnb46_g(s, query, N, ip, port, deadline) ;
+ if (r < 0) return 0 ;
+ if (r < N) return (errno = EPIPE, 0) ;
+ r = socket_recvnb46_g(s, answer, N, &dummyip, &dummyport, deadline) ;
+ if (r < 0) return 0 ;
+ if (r < N) return (errno = EPROTO, 0) ;
+ if (byte_diff(answer, 4, "stai")) return (errno = EPROTO, 0) ;
+ if (byte_diff(query+20, N-20, answer+20)) return (errno = EPROTO, 0) ;
+ tain_unpack(answer+4, serversays) ;
+ return 1 ;
+}
+
+int main (int argc, char const *const *argv)
+{
+ tain_t deltamin = TAIN_ZERO ;
+ tain_t deltaoffset ;
+ tain_t deltamax ;
+ tain_t errmax ;
+ tain_t timeouttto, throttletto, globaltto ;
+ tain_t globaldeadline ;
+ unsigned int roundtrips = 10 ;
+ unsigned int i = 0 ;
+ ip46_t ipremote ;
+ int sock ;
+ int flagforce = 0 ;
+ uint16 portremote = 4014 ;
+ PROG = "s6-taiclock" ;
+
+ {
+ unsigned int timeout = 2000 ;
+ unsigned int throttle = 0 ;
+ unsigned int bigtimeout = 10000 ;
+ unsigned int emax = 100 ;
+ subgetopt_t l = SUBGETOPT_ZERO ;
+ for (;;)
+ {
+ register int opt = subgetopt_r(argc, argv, "fv:r:t:h:T:e:p:", &l) ;
+ if (opt == -1) break ;
+ switch (opt)
+ {
+ case 'f' : flagforce = 1 ; break ;
+ case 'v' : if (!uint0_scan(l.arg, &verbosity)) dieusage() ; break ;
+ case 'r' : if (!uint0_scan(l.arg, &roundtrips)) dieusage() ; break ;
+ case 't' : if (!uint0_scan(l.arg, &timeout)) dieusage() ; break ;
+ case 'h' : if (!uint0_scan(l.arg, &throttle)) dieusage() ; break ;
+ case 'T' : if (!uint0_scan(l.arg, &bigtimeout)) dieusage() ; break ;
+ case 'e' : if (!uint0_scan(l.arg, &emax)) dieusage() ; break ;
+ case 'p' : if (!uint160_scan(l.arg, &portremote)) dieusage() ; break ;
+ default : dieusage() ;
+ }
+ }
+ argc -= l.ind ; argv += l.ind ;
+ if (timeout) tain_from_millisecs(&timeouttto, timeout) ;
+ else timeouttto = tain_infinite_relative ;
+ tain_from_millisecs(&throttletto, throttle) ;
+ if (bigtimeout) tain_from_millisecs(&globaltto, bigtimeout) ;
+ else globaltto = tain_infinite_relative ;
+ tain_from_millisecs(&errmax, emax) ;
+ }
+ if (!argc) dieusage() ;
+ if (!ip46_scan(argv[0], &ipremote)) dieusage() ;
+
+ sock = socket_udp46(ip46_is6(&ipremote)) ;
+ if (sock < 0) strerr_diefu1sys(111, "socket_udp") ;
+
+ tain_uint(&deltaoffset, 0xffffffffU) ;
+ tain_add(&deltaoffset, &deltaoffset, &deltaoffset) ; /* about 136 years */
+ tain_add(&deltamax, &deltaoffset, &deltaoffset) ;
+ tain_now_g() ;
+ tain_add_g(&globaldeadline, &globaltto) ;
+ if (!socket_deadlineconnstamp46_g(sock, &ipremote, portremote, &globaldeadline))
+ strerr_diefu1sys(111, "socket_deadlineconnstamp") ;
+
+ for (; i < roundtrips ; i++)
+ {
+ tain_t deadline, before, serversays ;
+ tain_add_g(&deadline, &timeouttto) ;
+ if (tain_less(&globaldeadline, &deadline)) deadline = globaldeadline ;
+ tain_copynow(&before) ;
+ if (!tain_exchange(sock, &ipremote, portremote, &serversays, &deadline))
+ {
+ if (verbosity >= 2)
+ {
+ char fmt[UINT_FMT] ;
+ char fmtr[UINT_FMT] ;
+ fmt[uint_fmt(fmt, i+1)] = 0 ;
+ fmtr[uint_fmt(fmtr, roundtrips)] = 0 ;
+ strerr_warni5sys("TAIA round-trip ", fmt, "/", fmtr, " failed") ;
+ }
+ }
+ else
+ {
+ tain_t cur, min, max ;
+ tain_add(&cur, &serversays, &deltaoffset) ;
+ tain_add(&min, &before, &deltamin) ;
+ tain_add(&max, &before, &deltamax) ;
+ if (tain_less(&cur, &max) && !tain_less(&cur, &min))
+ tain_sub(&deltamax, &cur, &before) ;
+ tain_add_g(&min, &deltamin) ;
+ tain_add_g(&max, &deltamax) ;
+ if (tain_less(&cur, &max) && !tain_less(&cur, &min))
+ tain_sub(&deltamin, &cur, &STAMP) ;
+ }
+
+ tain_add_g(&deadline, &throttletto) ;
+ if (tain_less(&globaldeadline, &deadline)) deadline = globaldeadline ;
+ deepsleepuntil_g(&deadline) ;
+ if (!tain_future(&globaldeadline))
+ {
+ if (verbosity)
+ {
+ errno = ETIMEDOUT ;
+ strerr_diefu1sys(1, "complete series of TAIA exchanges") ;
+ }
+ else return 1 ;
+ }
+ }
+
+ {
+ char adj[TAIN_PACK] ;
+ tain_t delta ;
+ if (tain_less(&deltamax, &deltamin)) tain_sub(&delta, &deltamin, &deltamax) ;
+ else tain_sub(&delta, &deltamax, &deltamin) ;
+ if (tain_less(&errmax, &delta))
+ {
+ if (verbosity)
+ {
+ char fmtd[TAIN_FMT] ;
+ char fmte[TAIN_FMT] ;
+ fmtd[tain_fmt(fmtd, &delta)] = 0 ;
+ fmte[tain_fmt(fmte, &errmax)] = 0 ;
+ strerr_warnw2x("maximum acceptable uncertainty: ", fmte) ;
+ strerr_warnw2x("current calculated uncertainty: ", fmtd) ;
+ }
+ if (!flagforce) strerr_dief1x(111, "time uncertainty too large") ;
+ }
+
+ tain_add(&delta, &deltamax, &deltamin) ;
+ tain_half(&delta, &delta) ;
+ tain_sub(&delta, &delta, &deltaoffset) ;
+ tain_pack(adj, &delta) ;
+ if (allwrite(1, adj, TAIN_PACK) < TAIN_PACK) strerr_diefu1sys(111, "write to stdout") ;
+ }
+ return 0 ;
+}