source/utils/net_time.c

   1 /*
   2    Samba Unix/Linux SMB client library
   3    net time command
   4    Copyright (C) 2001 Andrew Tridgell (tridge@samba.org)
   5
   6    This program 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 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
  18 */
  19 #include "includes.h"
  20 #include "utils/net.h"
  21
  22 /*
  23   return the time on a server. This does not require any authentication
  24 */
  25 static time_t cli_servertime(const char *host, struct sockaddr_storage *pss, int *zone)
  26 {
  27         struct nmb_name calling, called;
  28         time_t ret = 0;
  29         struct cli_state *cli = NULL;
  30         NTSTATUS status;
  31
  32         cli = cli_initialise();
  33         if (!cli) {
  34                 goto done;
  35         }
  36
  37         status = cli_connect(cli, host, pss);
  38         if (!NT_STATUS_IS_OK(status)) {
  39                 fprintf(stderr,"Can't contact server %s. Error %s\n", host, nt_errstr(status));
  40                 goto done;
  41         }
  42
  43         make_nmb_name(&calling, global_myname(), 0x0);
  44         if (host) {
  45                 make_nmb_name(&called, host, 0x20);
  46         } else {
  47                 make_nmb_name(&called, "*SMBSERVER", 0x20);
  48         }
  49
  50         if (!cli_session_request(cli, &calling, &called)) {
  51                 fprintf(stderr,"Session request failed\n");
  52                 goto done;
  53         }
  54         if (!cli_negprot(cli)) {
  55                 fprintf(stderr,"Protocol negotiation failed\n");
  56                 goto done;
  57         }
  58
  59         ret = cli->servertime;
  60         if (zone) *zone = cli->serverzone;
  61
  62 done:
  63         if (cli) {
  64                 cli_shutdown(cli);
  65         }
  66         return ret;
  67 }
  68
  69 /* find the servers time on the opt_host host */
  70 static time_t nettime(struct net_context *c, int *zone)
  71 {
  72         return cli_servertime(c->opt_host,
  73                               c->opt_have_ip? &c->opt_dest_ip : NULL, zone);
  74 }
  75
  76 /* return a time as a string ready to be passed to /bin/date */
  77 static const char *systime(time_t t)
  78 {
  79         static fstring s;
  80         struct tm *tm;
  81
  82         tm = localtime(&t);
  83         if (!tm) {
  84                 return "unknown";
  85         }
  86
  87         fstr_sprintf(s, "%02d%02d%02d%02d%04d.%02d",
  88                  tm->tm_mon+1, tm->tm_mday, tm->tm_hour,
  89                  tm->tm_min, tm->tm_year + 1900, tm->tm_sec);
  90         return s;
  91 }
  92
  93 int net_time_usage(struct net_context *c, int argc, const char **argv)
  94 {
  95         d_printf(
  96 "net time\n\tdisplays time on a server\n\n"
  97 "net time system\n\tdisplays time on a server in a format ready for /bin/date\n\n"
  98 "net time set\n\truns /bin/date with the time from the server\n\n"
  99 "net time zone\n\tdisplays the timezone in hours from GMT on the remote computer\n\n"
 100 "\n");
 101         net_common_flags_usage(c, argc, argv);
 102         return -1;
 103 }
 104
 105 /* try to set the system clock using /bin/date */
 106 static int net_time_set(struct net_context *c, int argc, const char **argv)
 107 {
 108         time_t t = nettime(c, NULL);
 109         char *cmd;
 110         int result;
 111
 112         if (t == 0) return -1;
 113
 114         /* yes, I know this is cheesy. Use "net time system" if you want to
 115            roll your own. I'm putting this in as it works on a large number
 116            of systems and the user has a choice in whether its used or not */
 117         if (asprintf(&cmd, "/bin/date %s", systime(t)) == -1) {
 118                 return -1;
 119         }
 120         result = system(cmd);
 121         if (result)
 122                 d_fprintf(stderr, "%s failed.  Error was (%s)\n",
 123                         cmd, strerror(errno));
 124         free(cmd);
 125
 126         return result;
 127 }
 128
 129 /* display the time on a remote box in a format ready for /bin/date */
 130 static int net_time_system(struct net_context *c, int argc, const char **argv)
 131 {
 132         time_t t;
 133
 134         if (c->display_usage) {
 135                 d_printf("Usage:\n"
 136                          "net time system\n"
 137                          "    Output remote time server time in a format ready "
 138                          "for /bin/date\n");
 139                 return 0;
 140         }
 141
 142         t = nettime(c, NULL);
 143         if (t == 0) return -1;
 144
 145         printf("%s\n", systime(t));
 146
 147         return 0;
 148 }
 149
 150 /* display the remote time server's offset to UTC */
 151 static int net_time_zone(struct net_context *c, int argc, const char **argv)
 152 {
 153         int zone = 0;
 154         int hours, mins;
 155         char zsign;
 156         time_t t;
 157
 158         if (c->display_usage) {
 159                 d_printf("Usage:\n"
 160                          "net time zone\n"
 161                          "   Display the remote time server's offset to UTC\n");
 162                 return 0;
 163         }
 164
 165         t = nettime(c, &zone);
 166
 167         if (t == 0) return -1;
 168
 169         zsign = (zone > 0) ? '-' : '+';
 170         if (zone < 0) zone = -zone;
 171
 172         zone /= 60;
 173         hours = zone / 60;
 174         mins = zone % 60;
 175
 176         printf("%c%02d%02d\n", zsign, hours, mins);
 177
 178         return 0;
 179 }
 180
 181 /* display or set the time on a host */
 182 int net_time(struct net_context *c, int argc, const char **argv)
 183 {
 184         time_t t;
 185         struct functable func[] = {
 186                 {
 187                         "system",
 188                         net_time_system,
 189                         NET_TRANSPORT_LOCAL,
 190                         "Display time ready for /bin/date",
 191                         "net time system\n"
 192                         "    Display time ready for /bin/date"
 193                 },
 194                 {
 195                         "set",
 196                         net_time_set,
 197                         NET_TRANSPORT_LOCAL,
 198                         "Set the system time from time server",
 199                         "net time set\n"
 200                         "    Set the system time from time server"
 201                 },
 202                 {
 203                         "zone",
 204                         net_time_zone,
 205                         NET_TRANSPORT_LOCAL,
 206                         "Display timezone offset from UTC",
 207                         "net time zone\n"
 208                         "    Display timezone offset from UTC"
 209                 },
 210                 {NULL, NULL, 0, NULL, NULL}
 211         };
 212
 213         if (argc != 0) {
 214                 return net_run_function(c, argc, argv, "net time", func);
 215         }
 216
 217         if (c->display_usage) {
 218                 d_printf("Usage:\n");
 219                 d_printf("net time\n"
 220                          "    Display the remote time server's time\n");
 221                 net_display_usage_from_functable(func);
 222                 return 0;
 223         }
 224
 225         if (!c->opt_host && !c->opt_have_ip &&
 226             !find_master_ip(c->opt_target_workgroup, &c->opt_dest_ip)) {
 227                 d_fprintf(stderr, "Could not locate a time server.  Try "
 228                                  "specifying a target host.\n");
 229                 net_time_usage(c, argc,argv);
 230                 return -1;
 231         }
 232
 233         /* default - print the time */
 234         t = cli_servertime(c->opt_host, c->opt_have_ip? &c->opt_dest_ip : NULL,
 235                            NULL);
 236         if (t == 0) return -1;
 237
 238         d_printf("%s", ctime(&t));
 239         return 0;
 240 }