1 files changed, 151 insertions, 2 deletions

diff --git a/src/lib/libcrypto/o_time.c b/src/lib/libcrypto/o_time.c
index e29091d650..eecbdd19f0 100644
--- a/src/lib/libcrypto/o_time.c
+++ b/src/lib/libcrypto/o_time.c
@@ -2,6 +2,9 @@
 /* Written by Richard Levitte (richard@levitte.org) for the OpenSSL
  * project 2001.
  */
+/* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
+ * project 2008.
+ */
 /* ====================================================================
  * Copyright (c) 2001 The OpenSSL Project.  All rights reserved.
  *
@@ -73,7 +76,7 @@ struct tm *OPENSSL_gmtime(const time_t *timer, struct tm *result)
         {
         struct tm *ts = NULL;
 
-#if defined(OPENSSL_THREADS) && !defined(OPENSSL_SYS_WIN32) && !defined(OPENSSL_SYS_OS2) && !defined(__CYGWIN32__) && (!defined(OPENSSL_SYS_VMS) || defined(gmtime_r)) && !defined(OPENSSL_SYS_MACOSX) && !defined(OPENSSL_SYS_SUNOS)
+#if defined(OPENSSL_THREADS) && !defined(OPENSSL_SYS_WIN32) && !defined(OPENSSL_SYS_OS2) && (!defined(OPENSSL_SYS_VMS) || defined(gmtime_r)) && !defined(OPENSSL_SYS_MACOSX) && !defined(OPENSSL_SYS_SUNOS)
         /* should return &data, but doesn't on some systems,
            so we don't even look at the return value */
         gmtime_r(timer,result);
@@ -214,4 +217,150 @@ struct tm *OPENSSL_gmtime(const time_t *timer, struct tm *result)
                 }
 #endif
         return ts;
-        }       
+        }
+
+/* Take a tm structure and add an offset to it. This avoids any OS issues
+ * with restricted date types and overflows which cause the year 2038
+ * problem.
+ */
+
+#define SECS_PER_DAY (24 * 60 * 60)
+
+static long date_to_julian(int y, int m, int d);
+static void julian_to_date(long jd, int *y, int *m, int *d);
+
+int OPENSSL_gmtime_adj(struct tm *tm, int off_day, long offset_sec)
+        {
+        int offset_hms, offset_day;
+        long time_jd;
+        int time_year, time_month, time_day;
+        /* split offset into days and day seconds */
+        offset_day = offset_sec / SECS_PER_DAY;
+        /* Avoid sign issues with % operator */
+        offset_hms  = offset_sec - (offset_day * SECS_PER_DAY);
+        offset_day += off_day;
+        /* Add current time seconds to offset */
+        offset_hms += tm->tm_hour * 3600 + tm->tm_min * 60 + tm->tm_sec;
+        /* Adjust day seconds if overflow */
+        if (offset_hms >= SECS_PER_DAY)
+                {
+                offset_day++;
+                offset_hms -= SECS_PER_DAY;
+                }
+        else if (offset_hms < 0)
+                {
+                offset_day--;
+                offset_hms += SECS_PER_DAY;
+                }
+
+        /* Convert date of time structure into a Julian day number.
+         */
+
+        time_year = tm->tm_year + 1900;
+        time_month = tm->tm_mon + 1;
+        time_day = tm->tm_mday;
+
+        time_jd = date_to_julian(time_year, time_month, time_day);
+
+        /* Work out Julian day of new date */
+        time_jd += offset_day;
+
+        if (time_jd < 0)
+                return 0;
+
+        /* Convert Julian day back to date */
+
+        julian_to_date(time_jd, &time_year, &time_month, &time_day);
+
+        if (time_year < 1900 || time_year > 9999)
+                return 0;
+
+        /* Update tm structure */
+
+        tm->tm_year = time_year - 1900;
+        tm->tm_mon = time_month - 1;
+        tm->tm_mday = time_day;
+
+        tm->tm_hour = offset_hms / 3600;
+        tm->tm_min = (offset_hms / 60) % 60;
+        tm->tm_sec = offset_hms % 60;
+
+        return 1;
+                
+}
+
+/* Convert date to and from julian day
+ * Uses Fliegel & Van Flandern algorithm
+ */
+static long date_to_julian(int y, int m, int d)
+{
+        return (1461 * (y + 4800 + (m - 14) / 12)) / 4 +
+                (367 * (m - 2 - 12 * ((m - 14) / 12))) / 12 -
+                (3 * ((y + 4900 + (m - 14) / 12) / 100)) / 4 +
+                d - 32075;
+}
+
+static void julian_to_date(long jd, int *y, int *m, int *d)
+        {
+        long  L = jd + 68569;
+        long  n = (4 * L) / 146097;
+        long  i, j;
+
+        L = L - (146097 * n + 3) / 4;
+        i = (4000 * (L + 1)) / 1461001;
+        L = L - (1461 * i) / 4 + 31;
+        j = (80 * L) / 2447;
+        *d = L - (2447 * j) / 80;
+        L = j / 11;
+        *m = j + 2 - (12 * L);
+        *y = 100 * (n - 49) + i + L;
+        }
+
+#ifdef OPENSSL_TIME_TEST
+
+#include <stdio.h>
+
+/* Time checking test code. Check times are identical for a wide range of
+ * offsets. This should be run on a machine with 64 bit time_t or it will
+ * trigger the very errors the routines fix.
+ */
+
+int main(int argc, char **argv)
+        {
+        long offset;
+        for (offset = 0; offset < 1000000; offset++)
+                {
+                check_time(offset);
+                check_time(-offset);
+                check_time(offset * 1000);
+                check_time(-offset * 1000);
+                }
+        }
+
+int check_time(long offset)
+        {
+        struct tm tm1, tm2;
+        time_t t1, t2;
+        time(&t1);
+        t2 = t1 + offset;
+        OPENSSL_gmtime(&t2, &tm2);
+        OPENSSL_gmtime(&t1, &tm1);
+        OPENSSL_gmtime_adj(&tm1, 0, offset);
+        if ((tm1.tm_year == tm2.tm_year) &&
+            (tm1.tm_mon == tm2.tm_mon) &&
+            (tm1.tm_mday == tm2.tm_mday) &&
+            (tm1.tm_hour == tm2.tm_hour) &&
+            (tm1.tm_min == tm2.tm_min) &&
+            (tm1.tm_sec == tm2.tm_sec))
+                return 1;
+        fprintf(stderr, "TIME ERROR!!\n");
+        fprintf(stderr, "Time1: %d/%d/%d, %d:%02d:%02d\n",
+                        tm2.tm_mday, tm2.tm_mon + 1, tm2.tm_year + 1900,
+                        tm2.tm_hour, tm2.tm_min, tm2.tm_sec);
+        fprintf(stderr, "Time2: %d/%d/%d, %d:%02d:%02d\n",
+                        tm1.tm_mday, tm1.tm_mon + 1, tm1.tm_year + 1900,
+                        tm1.tm_hour, tm1.tm_min, tm1.tm_sec);
+        return 0;
+        }
+
+#endif