1 /* 2 * ntpdate.h - declarations for the ntpdate and ntptimeset programs 3 */ 4 5 #include "ntp_malloc.h" 6 7 extern void loadservers P((char *cfgpath)); 8 9 /* 10 * The server structure is a much simplified version of the 11 * peer structure, for ntpdate's use. Since we always send 12 * in client mode and expect to receive in server mode, this 13 * leaves only a very limited number of things we need to 14 * remember about the server. 15 */ 16 struct server { 17 struct server *next_server; /* next server in build list */ 18 struct sockaddr_storage srcadr; /* address of remote host */ 19 u_char version; /* version to use */ 20 u_char leap; /* leap indicator */ 21 u_char stratum; /* stratum of remote server */ 22 s_char precision; /* server's clock precision */ 23 u_char trust; /* trustability of the filtered data */ 24 u_fp rootdelay; /* distance from primary clock */ 25 u_fp rootdispersion; /* peer clock dispersion */ 26 u_int32 refid; /* peer reference ID */ 27 l_fp reftime; /* time of peer's last update */ 28 u_long event_time; /* time for next timeout */ 29 u_long last_xmit; /* time of last transmit */ 30 u_short xmtcnt; /* number of packets transmitted */ 31 u_short rcvcnt; /* number of packets received */ 32 u_char reach; /* reachability, NTP_WINDOW bits */ 33 u_short filter_nextpt; /* index into filter shift register */ 34 s_fp filter_delay[NTP_SHIFT]; /* delay part of shift register */ 35 l_fp filter_offset[NTP_SHIFT]; /* offset part of shift register */ 36 s_fp filter_soffset[NTP_SHIFT]; /* offset in s_fp format, for disp */ 37 u_fp filter_error[NTP_SHIFT]; /* error part of shift register */ 38 l_fp org; /* peer's originate time stamp */ 39 l_fp xmt; /* transmit time stamp */ 40 u_fp delay; /* filter estimated delay */ 41 u_fp dispersion; /* filter estimated dispersion */ 42 l_fp offset; /* filter estimated clock offset */ 43 s_fp soffset; /* fp version of above */ 44 }; 45 46 47 /* 48 * ntpdate runs everything on a simple, short timeout. It sends a 49 * packet and sets the timeout (by default, to a small value suitable 50 * for a LAN). If it receives a response it sends another request. 51 * If it times out it shifts zeroes into the filter and sends another 52 * request. 53 * 54 * The timer routine is run often (once every 1/5 second currently) 55 * so that time outs are done with reasonable precision. 56 */ 57 #define TIMER_HZ (5) /* 5 per second */ 58 59 /* 60 * ntpdate will make a long adjustment using adjtime() if the times 61 * are close, or step the time if the times are farther apart. The 62 * following defines what is "close". 63 */ 64 #define NTPDATE_THRESHOLD (FP_SECOND >> 1) /* 1/2 second */ 65 66 #define NTP_MAXAGE 86400 /* one day in seconds */ 67 68 /* 69 * When doing adjustments, ntpdate actually overadjusts (currently 70 * by 50%, though this may change). While this will make it take longer 71 * to reach a steady state condition, it will typically result in 72 * the clock keeping more accurate time, on average. The amount of 73 * overshoot is limited. 74 */ 75 #ifdef NOTNOW 76 #define ADJ_OVERSHOOT 1/2 /* this is hard coded */ 77 #endif /* NOTNOW */ 78 #define ADJ_MAXOVERSHOOT 0x10000000 /* 50 ms as a ts fraction */ 79 80 /* 81 * Since ntpdate isn't aware of some of the things that normally get 82 * put in an NTP packet, we fix some values. 83 */ 84 #define NTPDATE_PRECISION (-6) /* use this precision */ 85 #define NTPDATE_DISTANCE FP_SECOND /* distance is 1 sec */ 86 #define NTPDATE_DISP FP_SECOND /* so is the dispersion */ 87 #define NTPDATE_REFID (0) /* reference ID to use */ 88 #define PEER_MAXDISP (64*FP_SECOND) /* maximum dispersion (fp 64) */ 89 90 91 /* 92 * Some defaults 93 */ 94 #define DEFTIMEOUT 5 /* 5 timer increments */ 95 #define DEFSAMPLES 4 /* get 4 samples per server */ 96 #define DEFPRECISION (-5) /* the precision we claim */ 97 #define DEFMAXPERIOD 60 /* maximum time to wait */ 98 #define DEFMINSERVERS 3 /* minimum responding servers */ 99 #define DEFMINVALID 1 /* mimimum servers with valid time */ 100 101 /* 102 * Define the max number of sockets we can open 103 */ 104 #define MAX_AF 2 105