lib/gztime.c

   1 /* gztime.c --- Convertion functions for GeneralizedTime.
   2  * Copyright (C) 2002, 2003, 2004, 2006  Simon Josefsson
   3  *
   4  * This file is part of Shishi.
   5  *
   6  * Shishi is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * Shishi is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with Shishi; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
  19  *
  20  */
  21
  22 #include "internal.h"
  23
  24 /* Get xtime. */
  25 #include "utils.h"
  26
  27 /* Get timegm. */
  28 #include "timegm.h"
  29
  30 /**
  31  * shishi_generalize_time:
  32  * @handle: shishi handle as allocated by shishi_init().
  33  * @t: C time to convert.
  34  *
  35  * Convert C time to KerberosTime.  The string must not be deallocate
  36  * by caller.
  37  *
  38  * Return value: Return a KerberosTime time string corresponding to C time t.
  39  **/
  40 const char *
  41 shishi_generalize_time (Shishi * handle, time_t t)
  42 {
  43   struct tm *tm;
  44
  45   tm = gmtime (&t);
  46   strftime (handle->gztime_buf, sizeof (handle->gztime_buf),
  47             "%Y%m%d%H%M%SZ", tm);
  48
  49   return handle->gztime_buf;
  50 }
  51
  52 /**
  53  * shishi_generalize_now:
  54  * @handle: shishi handle as allocated by shishi_init().
  55  *
  56  * Convert current time to KerberosTime.  The string must not be
  57  * deallocate by caller.
  58  *
  59  * Return value: Return a KerberosTime time string corresponding to
  60  *   current time.
  61  **/
  62 const char *
  63 shishi_generalize_now (Shishi * handle)
  64 {
  65   time_t t = xtime (NULL);
  66
  67   return shishi_generalize_time (handle, t);
  68 }
  69
  70 /**
  71  * shishi_generalize_ctime:
  72  * @handle: shishi handle as allocated by shishi_init().
  73  * @t: KerberosTime to convert.
  74  *
  75  * Convert KerberosTime to C time.
  76  *
  77  * Return value: Returns C time corresponding to KerberosTime t.
  78  **/
  79 time_t
  80 shishi_generalize_ctime (Shishi * handle, const char *t)
  81 {
  82   struct tm tm;
  83   time_t ct;
  84
  85   memset (&tm, 0, sizeof (tm));
  86
  87   sscanf (t, "%4u%2u%2u%2u%2u%2uZ",
  88           &tm.tm_year, &tm.tm_mon, &tm.tm_mday,
  89           &tm.tm_hour, &tm.tm_min, &tm.tm_sec);
  90   tm.tm_year -= 1900;
  91   tm.tm_mon--;
  92
  93   ct = timegm (&tm);
  94
  95   return ct;
  96 }
  97
  98 /**
  99  * shishi_time:
 100  * @handle: shishi handle as allocated by shishi_init().
 101  * @node: ASN.1 node to get time from.
 102  * @field: Name of field in ASN.1 node to get time from.
 103  * @t: newly allocated output array with zero terminated time string.
 104  *
 105  * Extract time from ASN.1 structure.
 106  *
 107  * Return value: Returns SHISHI_OK iff successful.
 108  **/
 109 int
 110 shishi_time (Shishi * handle, Shishi_asn1 node, const char *field, char **t)
 111 {
 112   size_t len;
 113   int res;
 114
 115   len = SHISHI_GENERALIZEDTIME_LENGTH + 1;
 116   *t = xmalloc (len);
 117
 118   res = shishi_asn1_read_inline (handle, node, field, *t, &len);
 119   if (res != SHISHI_OK)
 120     return res;
 121
 122   if (len <= SHISHI_GENERALIZEDTIME_LENGTH)
 123     {
 124       shishi_error_printf (handle, "Read time too short (%s)", *t);
 125       return SHISHI_ASN1_ERROR;
 126     }
 127
 128   (*t)[SHISHI_GENERALIZEDTIME_LENGTH] = '\0';
 129
 130   return SHISHI_OK;
 131 }
 132
 133 /**
 134  * shishi_ctime:
 135  * @handle: shishi handle as allocated by shishi_init().
 136  * @node: ASN.1 variable to read field from.
 137  * @field: name of field in @node to read.
 138  * @t: pointer to time field to set.
 139  *
 140  * Extract time from ASN.1 structure.
 141  *
 142  * Return value: Returns SHISHI_OK if successful,
 143  *   SHISHI_ASN1_NO_ELEMENT if the element do not exist,
 144  *   SHISHI_ASN1_NO_VALUE if the field has no value, ot
 145  *   SHISHI_ASN1_ERROR otherwise.
 146  **/
 147 int
 148 shishi_ctime (Shishi * handle, Shishi_asn1 node, const char *field, time_t *t)
 149 {
 150   char str[SHISHI_GENERALIZEDTIME_LENGTH + 1];
 151   size_t strlen = sizeof (str);
 152   int rc;
 153
 154   rc = shishi_asn1_read_inline (handle, node, field, str, &strlen);
 155   if (rc != SHISHI_OK)
 156     return rc;
 157
 158   *t = shishi_generalize_ctime (handle, str);
 159
 160   return SHISHI_OK;
 161 }