Experimental new date handling routines. These fix issues with X509_time_adj()

and should avoid any OS date limitations such as the year 2038 bug.

1 files changed, 150 insertions, 1 deletions

diff --git a/crypto/o_time.c b/crypto/o_time.c
index 607556b0a6..eecbdd19f0 100644
--- a/crypto/o_time.c
+++ b/crypto/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.
  *
@@ -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