[Bug 3424] Trimble Thunderbolt 1024 week millenium bug

bk: 599f313cOs1FsBCriJ19G1j4DjsBuA

diff --git a/ChangeLog b/ChangeLog
index a1a1cfae45a59975bb12958d206f6c0a48e631b5..4dd2249df8af46012e523f43ada7cce5d9cd6e21 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+---
+* [Bug 3424] Trimble Thunderbolt 1024 week millenium bug <perlinger@ntp.org>
+  - initial patch by Daniel Pouzzner
+
 ---
 (4.2.8p10-win-beta1) 2017/03/21 Released by Harlan Stenn <stenn@ntp.org>
 (4.2.8p10)

diff --git a/ntpd/refclock_palisade.c b/ntpd/refclock_palisade.c
index 921c815ce163a751b789ff782ba20746251c233f..0289dd2c15e6fc2fe61d7d5c01632c33c85b93fb 100644 (file)
--- a/ntpd/refclock_palisade.c
+++ b/ntpd/refclock_palisade.c
@@ -80,10 +80,6 @@ extern int async_write(int, const void *, unsigned int);
 #endif
 
 #include "refclock_palisade.h"
-/* Table to get from month to day of the year */
-const int days_of_year [12] = {
-       0,  31,  59,  90, 120, 151, 181, 212, 243, 273, 304, 334
-};
 
 #ifdef DEBUG
 const char * Tracking_Status[15][15] = { 
@@ -107,7 +103,7 @@ struct refclock refclock_palisade = {
        NOFLAGS                 /* not used */
 };
 
-int day_of_year (char *dt);
+static int decode_date(struct refclockproc *pp, const char *cp);
 
 /* Extract the clock type from the mode setting */
 #define CLK_TYPE(x) ((int)(((x)->ttl) & 0x7F))
@@ -400,33 +396,78 @@ palisade_shutdown (
 }
 
 
-
 /* 
- * unpack_date - get day and year from date
+ * unpack helpers
  */
-int
-day_of_year (
-       char * dt
-       )
-{
-       int day, mon, year;
 
-       mon = dt[1];
-       /* Check month is inside array bounds */
-       if ((mon < 1) || (mon > 12)) 
-               return -1;
+static inline uint8_t
+get_u8(
+       const char *cp)
+{
+       return ((const u_char*)cp)[0];
+}
 
-       day = dt[0] + days_of_year[mon - 1];
-       year = getint((u_char *) (dt + 2)); 
+static inline uint16_t
+get_u16(
+       const char *cp)
+{
+       return ((uint16_t)get_u8(cp) << 8) | get_u8(cp + 1);
+}
 
-       if ( !(year % 4) && ((year % 100) || 
-                            (!(year % 100) && !(year%400)))
-            &&(mon > 2))
-               day ++; /* leap year and March or later */
+/*
+ * unpack & fix date (the receiver provides a valid time for 1024 weeks
+ * after 1997-12-14 and therefore folds back in 2017, 2037,...)
+ *
+ * Returns -1 on error, day-of month + (month * 32) othertwise.
+ */
+int
+decode_date(
+       struct refclockproc *pp,
+       const char          *cp)
+{
+       static uint32_t s_baseday = 0;
+       
+       struct calendar jd;
+       int32_t         rd;
+
+       if (0 == s_baseday) {
+               if (!ntpcal_get_build_date(&jd)) {
+                       jd.year     = 2015;
+                       jd.month    = 1;
+                       jd.monthday = 1;
+               }
+               s_baseday = ntpcal_date_to_rd(&jd);
+       }
 
-       return day;
+       /* get date fields and convert to RDN */
+       jd.monthday = get_u8 (  cp  );
+       jd.month    = get_u8 (cp + 1);
+       jd.year     = get_u16(cp + 2);
+       rd = ntpcal_date_to_rd(&jd);
+
+       /* for the paranoid: do reverse calculation and cross-check */
+       ntpcal_rd_to_date(&jd, rd);
+       if ((jd.monthday != get_u8 (  cp  )) ||
+           (jd.month    != get_u8 (cp + 1)) ||
+           (jd.year     != get_u16(cp + 2))  )
+               return - 1;
+       
+       /* calculate cycle shift to base day and calculate re-folded
+        * date
+        *
+        * One could do a proper modulo calculation here, but a counting
+        * loop is probably faster for the next few rollovers...
+        */
+       while (rd < s_baseday)
+               rd += 7*1024;
+       ntpcal_rd_to_date(&jd, rd);
+
+       /* fill refclock structure & indicate success */
+       pp->day  = jd.yearday;
+       pp->year = jd.year;     
+       return ((int)jd.month << 5) | jd.monthday;
 }
-
+    
 
 /* 
  * TSIP_decode - decode the TSIP data packets 
@@ -441,7 +482,8 @@ TSIP_decode (
        double secs;
        double secfrac;
        unsigned short event = 0;
-
+       int mmday;
+       
        struct palisade_unit *up;
        struct refclockproc *pp;
 
@@ -535,16 +577,16 @@ TSIP_decode (
                        pp->minute = secint / 60;
                        secint %= 60;
                        pp->second = secint % 60;
-               
-                       if ((pp->day = day_of_year(&mb(11))) < 0) break;
 
-                       pp->year = getint((u_char *) &mb(13)); 
+                       mmday = decode_date(pp, &mb(11));
+                       if (mmday < 0)
+                               break;
 
 #ifdef DEBUG
                        if (debug > 1)
                                printf("TSIP_decode: unit %d: %02X #%d %02d:%02d:%02d.%09ld %02d/%02d/%04d UTC %02d\n",
                                       up->unit, mb(0) & 0xff, event, pp->hour, pp->minute, 
-                                      pp->second, pp->nsec, mb(12), mb(11), pp->year, GPS_UTC_Offset);
+                                      pp->second, pp->nsec, (mmday >> 5), (mmday & 31), pp->year, GPS_UTC_Offset);
 #endif
                        /* Only use this packet when no
                         * 8F-AD's are being received
@@ -584,7 +626,11 @@ TSIP_decode (
                                break;
                        }
 
-                       up->month = mb(15);
+                       mmday = decode_date(pp, &mb(14));
+                       if (mmday < 0)
+                               break;
+                       up->month  = (mmday >> 5);  /* Save for LEAP check */
+
                        if ( (up->leap_status & PALISADE_LEAP_PENDING) &&
                        /* Avoid early announce: https://bugs.ntp.org/2773 */
                                (6 == up->month || 12 == up->month) ) {
@@ -612,19 +658,15 @@ TSIP_decode (
                        pp->nsec = (long) (getdbl((u_char *) &mb(3))
                                           * 1000000000);
 
-                       if ((pp->day = day_of_year(&mb(14))) < 0) 
-                               break;
-                       pp->year = getint((u_char *) &mb(16)); 
                        pp->hour = mb(11);
                        pp->minute = mb(12);
                        pp->second = mb(13);
-                       up->month = mb(14);  /* Save for LEAP check */
 
 #ifdef DEBUG
                        if (debug > 1)
                                printf("TSIP_decode: unit %d: %02X #%d %02d:%02d:%02d.%09ld %02d/%02d/%04d UTC %02x %s\n",
                                       up->unit, mb(0) & 0xff, event, pp->hour, pp->minute, 
-                                      pp->second, pp->nsec, mb(15), mb(14), pp->year,
+                                      pp->second, pp->nsec, (mmday >> 5), (mmday & 31), pp->year,
                                       mb(19), *Tracking_Status[st]);
 #endif
                        return 1;
@@ -750,17 +792,17 @@ TSIP_decode (
                                printf ("       Time is from GPS\n\n"); 
 #endif         
 
-                       if ((pp->day = day_of_year(&mb(13))) < 0)
+                       mmday = decode_date(pp, &mb(13));
+                       if (mmday < 0)
                                break;
                        tow = getlong((u_char *) &mb(1));
 #ifdef DEBUG           
                        if (debug > 1) {
                                printf("pp->day: %d\n", pp->day); 
                                printf("TOW: %ld\n", tow);
-                               printf("DAY: %d\n", mb(13));
+                               printf("DAY: %d\n", (mmday & 31));
                        }
 #endif
-                       pp->year = getint((u_char *) &mb(15));
                        pp->hour = mb(12);
                        pp->minute = mb(11);
                        pp->second = mb(10);
@@ -768,7 +810,9 @@ TSIP_decode (
 
 #ifdef DEBUG
                        if (debug > 1)
-                               printf("TSIP_decode: unit %d: %02X #%d %02d:%02d:%02d.%09ld %02d/%02d/%04d ",up->unit, mb(0) & 0xff, event, pp->hour, pp->minute, pp->second, pp->nsec, mb(14), mb(13), pp->year);
+                               printf("TSIP_decode: unit %d: %02X #%d %02d:%02d:%02d.%09ld %02d/%02d/%04d ",
+                                      up->unit, mb(0) & 0xff, event, pp->hour, pp->minute, pp->second,
+                                      pp->nsec, (mmday >> 5), (mmday & 31), pp->year);
 #endif
                        return 1;
                        break;