diff options
Diffstat (limited to 'src/clock/s6-taiclock.c')
| -rw-r--r-- | src/clock/s6-taiclock.c | 182 |
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 ; +} |