/*****************************************************************************
*
* Monitoring check_by_ssh plugin
*
* License: GPL
* Copyright (c) 2000-2008 Monitoring Plugins Development Team
*
* Description:
*
* This file contains the check_by_ssh plugin
*
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program.  If not, see <http://www.gnu.org/licenses/>.
*
*
*****************************************************************************/

const char *progname = "check_by_ssh";
const char *copyright = "2000-2008";
const char *email = "devel@monitoring-plugins.org";

#include "common.h"
#include "utils.h"
#include "netutils.h"
#include "utils_cmd.h"

#ifndef NP_MAXARGS
#define NP_MAXARGS 1024
#endif

int process_arguments (int, char **);
int validate_arguments (void);
void comm_append (const char *);
void print_help (void);
void print_usage (void);

unsigned int commands = 0;
unsigned int services = 0;
int skip_stdout = 0;
int skip_stderr = 0;
char *remotecmd = NULL;
char **commargv = NULL;
int commargc = 0;
char *hostname = NULL;
char *outputfile = NULL;
char *host_shortname = NULL;
char **service;
int passive = FALSE;
int verbose = FALSE;

int
main (int argc, char **argv)
{

        char *status_text;
        int cresult;
        int result = STATE_UNKNOWN;
        int i;
        time_t local_time;
        FILE *fp = NULL;
        output chld_out, chld_err;

        remotecmd = "";
        comm_append(SSH_COMMAND);

        setlocale (LC_ALL, "");
        bindtextdomain (PACKAGE, LOCALEDIR);
        textdomain (PACKAGE);

        /* Parse extra opts if any */
        argv=np_extra_opts (&argc, argv, progname);

        /* process arguments */
        if (process_arguments (argc, argv) == ERROR)
                usage_va(_("Could not parse arguments"));

        /* Set signal handling and alarm timeout */
        if (signal (SIGALRM, timeout_alarm_handler) == SIG_ERR) {
                usage_va(_("Cannot catch SIGALRM"));
        }
        alarm (timeout_interval);

        /* run the command */
        if (verbose) {
                printf ("Command: %s\n", commargv[0]);
                for (i=1; i<commargc; i++)
                        printf ("Argument %i: %s\n", i, commargv[i]);
        }

        result = cmd_run_array (commargv, &chld_out, &chld_err, 0);

        if (skip_stdout == -1) /* --skip-stdout specified without argument */
                skip_stdout = chld_out.lines;
        if (skip_stderr == -1) /* --skip-stderr specified without argument */
                skip_stderr = chld_err.lines;

        /* UNKNOWN or worse if (non-skipped) output found on stderr */
        if(chld_err.lines > skip_stderr) {
                printf (_("Remote command execution failed: %s\n"),
                        chld_err.line[skip_stderr]);
                return max_state_alt(result, STATE_UNKNOWN);
        }

        /* this is simple if we're not supposed to be passive.
         * Wrap up quickly and keep the tricks below */
        if(!passive) {
                if (chld_out.lines > skip_stdout)
                        for (i = skip_stdout; i < chld_out.lines; i++)
                                puts (chld_out.line[i]);
                else
                        printf (_("%s - check_by_ssh: Remote command '%s' returned status %d\n"),
                                state_text(result), remotecmd, result);
                return result;  /* return error status from remote command */
        }


        /*
         * Passive mode
         */

        /* process output */
        if (!(fp = fopen (outputfile, "a"))) {
                printf (_("SSH WARNING: could not open %s\n"), outputfile);
                exit (STATE_UNKNOWN);
        }

        local_time = time (NULL);
        commands = 0;
        for(i = skip_stdout; i < chld_out.lines; i++) {
                status_text = chld_out.line[i++];
                if (i == chld_out.lines || strstr (chld_out.line[i], "STATUS CODE: ") == NULL)
                        die (STATE_UNKNOWN, _("%s: Error parsing output\n"), progname);

                if (service[commands] && status_text
                        && sscanf (chld_out.line[i], "STATUS CODE: %d", &cresult) == 1)
                {
                        fprintf (fp, "[%d] PROCESS_SERVICE_CHECK_RESULT;%s;%s;%d;%s\n",
                                 (int) local_time, host_shortname, service[commands++],
                                 cresult, status_text);
                }
        }

        /* Multiple commands and passive checking should always return OK */
        return result;
}

/* process command-line arguments */
int
process_arguments (int argc, char **argv)
{
        int c;
        char *p1, *p2;

        int option = 0;
        static struct option longopts[] = {
                {"version", no_argument, 0, 'V'},
                {"help", no_argument, 0, 'h'},
                {"verbose", no_argument, 0, 'v'},
                {"fork", no_argument, 0, 'f'},
                {"timeout", required_argument, 0, 't'},
                {"host", required_argument, 0, 'H'},    /* backward compatibility */
                {"hostname", required_argument, 0, 'H'},
                {"port", required_argument,0,'p'},
                {"output", required_argument, 0, 'O'},
                {"name", required_argument, 0, 'n'},
                {"services", required_argument, 0, 's'},
                {"identity", required_argument, 0, 'i'},
                {"user", required_argument, 0, 'u'},
                {"logname", required_argument, 0, 'l'},
                {"command", required_argument, 0, 'C'},
                {"skip", optional_argument, 0, 'S'}, /* backwards compatibility */
                {"skip-stdout", optional_argument, 0, 'S'},
                {"skip-stderr", optional_argument, 0, 'E'},
                {"proto1", no_argument, 0, '1'},
                {"proto2", no_argument, 0, '2'},
                {"use-ipv4", no_argument, 0, '4'},
                {"use-ipv6", no_argument, 0, '6'},
                {"ssh-option", required_argument, 0, 'o'},
                {"force-tty", no_argument, 0, 'z'},
                {"quiet", no_argument, 0, 'q'},
                {"configfile", optional_argument, 0, 'F'},
                {0, 0, 0, 0}
        };

        if (argc < 2)
                return ERROR;

        for (c = 1; c < argc; c++)
                if (strcmp ("-to", argv[c]) == 0)
                        strcpy (argv[c], "-t");

        while (1) {
                c = getopt_long (argc, argv, "Vvh1246fzqt:H:O:p:i:u:l:C:S::E::n:s:o:F:", longopts,
                                 &option);

                if (c == -1 || c == EOF)
                        break;

                switch (c) {
                case 'V':                                                                       /* version */
                        print_revision (progname, NP_VERSION);
                        exit (STATE_OK);
                case 'h':                                                                       /* help */
                        print_help ();
                        exit (STATE_OK);
                case 'v':                                                                       /* help */
                        verbose = TRUE;
                        break;
                case 't':                                                                       /* timeout period */
                        if (!is_integer (optarg))
                                usage_va(_("Timeout interval must be a positive integer"));
                        else
                                timeout_interval = atoi (optarg);
                        break;
                case 'H':                                                                       /* host */
                        host_or_die(optarg);
                        hostname = optarg;
                        break;
                case 'p': /* port number */
                        if (!is_integer (optarg))
                                usage_va(_("Port must be a positive integer"));
                        comm_append("-p");
                        comm_append(optarg);
                        break;
                case 'O':                                                                       /* output file */
                        outputfile = optarg;
                        passive = TRUE;
                        break;
                case 's':                                                                       /* description of service to check */
                        p1 = optarg;
                        service = realloc (service, (++services) * sizeof(char *));
                        while ((p2 = index (p1, ':'))) {
                                *p2 = '\0';
                                service[services - 1] = p1;
                                service = realloc (service, (++services) * sizeof(char *));
                                p1 = p2 + 1;
                        }
                        service[services - 1] = p1;
                        break;
                case 'n':                                                                       /* short name of host in the monitoring configuration */
                        host_shortname = optarg;
                        break;

                case 'u':
                        comm_append("-l");
                        comm_append(optarg);
                        break;
                case 'l':                                                                       /* login name */
                        comm_append("-l");
                        comm_append(optarg);
                        break;
                case 'i':                                                                       /* identity */
                        comm_append("-i");
                        comm_append(optarg);
                        break;

                case '1':                                                                       /* Pass these switches directly to ssh */
                        comm_append("-1");
                        break;
                case '2':                                                                       /* 1 to force version 1, 2 to force version 2 */
                        comm_append("-2");
                        break;
                case '4':                                                                       /* -4 for IPv4 */
                        comm_append("-4");
                        break;
                case 'z':                                                                       /* -4 for IPv4 */
                        comm_append("-t");
                        break;
                case '6':                                                               /* -6 for IPv6 */
                        comm_append("-6");
                        break;
                case 'f':                                                                       /* fork to background */
                        comm_append("-f");
                        break;
                case 'C':                                                                       /* Command for remote machine */
                        commands++;
                        if (commands > 1)
                                xasprintf (&remotecmd, "%s;echo STATUS CODE: $?;", remotecmd);
                        xasprintf (&remotecmd, "%s%s", remotecmd, optarg);
                        break;
                case 'S':                                                                       /* skip n (or all) lines on stdout */
                        if (optarg == NULL)
                                skip_stdout = -1; /* skip all output on stdout */
                        else if (!is_integer (optarg))
                                usage_va(_("skip-stdout argument must be an integer"));
                        else
                                skip_stdout = atoi (optarg);
                        break;
                case 'E':                                                                       /* skip n (or all) lines on stderr */
                        if (optarg == NULL)
                                skip_stderr = -1; /* skip all output on stderr */
                        else if (!is_integer (optarg))
                                usage_va(_("skip-stderr argument must be an integer"));
                        else
                                skip_stderr = atoi (optarg);
                        break;
                case 'o':                                                                       /* Extra options for the ssh command */
                        comm_append("-o");
                        comm_append(optarg);
                        break;
                case 'q':                                                                       /* Tell the ssh command to be quiet */
                        comm_append("-q");
                        break;
                case 'F':                                                                       /* ssh configfile */
                        comm_append("-F");
                        comm_append(optarg);
                        break;
                default:                                                                        /* help */
                        usage5();
                }
        }

        c = optind;
        if (hostname == NULL) {
                if (c <= argc) {
                        die (STATE_UNKNOWN, _("%s: You must provide a host name\n"), progname);
                }
                host_or_die(argv[c]);
                hostname = argv[c++];
        }

        if (strlen(remotecmd) == 0) {
                for (; c < argc; c++)
                        if (strlen(remotecmd) > 0)
                                xasprintf (&remotecmd, "%s %s", remotecmd, argv[c]);
                        else
                                xasprintf (&remotecmd, "%s", argv[c]);
        }

        if (commands > 1 || passive)
                xasprintf (&remotecmd, "%s;echo STATUS CODE: $?;", remotecmd);

        if (remotecmd == NULL || strlen (remotecmd) <= 1)
                usage_va(_("No remotecmd"));

        comm_append(hostname);
        comm_append(remotecmd);

        return validate_arguments ();
}


void
comm_append (const char *str)
{

        if (++commargc > NP_MAXARGS)
                die(STATE_UNKNOWN, _("%s: Argument limit of %d exceeded\n"), progname, NP_MAXARGS);

        if ((commargv = (char **)realloc(commargv, (commargc+1) * sizeof(char *))) == NULL)
                die(STATE_UNKNOWN, _("Can not (re)allocate 'commargv' buffer\n"));

        commargv[commargc-1] = strdup(str);
        commargv[commargc] = NULL;

}

int
validate_arguments (void)
{
        if (remotecmd == NULL || hostname == NULL)
                return ERROR;

        if (passive && commands != services)
                die (STATE_UNKNOWN, _("%s: In passive mode, you must provide a service name for each command.\n"), progname);

        if (passive && host_shortname == NULL)
                die (STATE_UNKNOWN, _("%s: In passive mode, you must provide the host short name from the monitoring configs.\n"), progname);

        return OK;
}


void
print_help (void)
{
        print_revision (progname, NP_VERSION);

        printf ("Copyright (c) 1999 Karl DeBisschop <kdebisschop@users.sourceforge.net>\n");
        printf (COPYRIGHT, copyright, email);

        printf (_("This plugin uses SSH to execute commands on a remote host"));

  printf ("\n\n");

        print_usage ();

        printf (UT_HELP_VRSN);

        printf (UT_EXTRA_OPTS);

        printf (UT_HOST_PORT, 'p', "none");

        printf (UT_IPv46);

  printf (" %s\n", "-1, --proto1");
  printf ("    %s\n", _("tell ssh to use Protocol 1 [optional]"));
  printf (" %s\n", "-2, --proto2");
  printf ("    %s\n", _("tell ssh to use Protocol 2 [optional]"));
  printf (" %s\n", "-S, --skip-stdout[=n]");
  printf ("    %s\n", _("Ignore all or (if specified) first n lines on STDOUT [optional]"));
  printf (" %s\n", "-E, --skip-stderr[=n]");
  printf ("    %s\n", _("Ignore all or (if specified) first n lines on STDERR [optional]"));
  printf (" %s\n", "-f");
  printf ("    %s\n", _("tells ssh to fork rather than create a tty [optional]. This will always return OK if ssh is executed"));
  printf (" %s\n","-C, --command='COMMAND STRING'");
  printf ("    %s\n", _("command to execute on the remote machine"));
  printf (" %s\n","-l, --logname=USERNAME");
  printf ("    %s\n", _("SSH user name on remote host [optional]"));
  printf (" %s\n","-i, --identity=KEYFILE");
  printf ("    %s\n", _("identity of an authorized key [optional]"));
  printf (" %s\n","-O, --output=FILE");
  printf ("    %s\n", _("external command file for monitoring [optional]"));
  printf (" %s\n","-s, --services=LIST");
  printf ("    %s\n", _("list of monitoring service names, separated by ':' [optional]"));
  printf (" %s\n","-n, --name=NAME");
  printf ("    %s\n", _("short name of host in the monitoring configuration [optional]"));
  printf (" %s\n","-z, --force-tty");
  printf ("    %s\n", _("Call ssh with '-t' to force pseudo tty allocation. Has to be used in conjunction with -E [optional]"));
  printf (" %s\n","-o, --ssh-option=OPTION");
  printf ("    %s\n", _("Call ssh with '-o OPTION' (may be used multiple times) [optional]"));
  printf (" %s\n","-F, --configfile");
  printf ("    %s\n", _("Tell ssh to use this configfile [optional]"));
  printf (" %s\n","-q, --quiet");
  printf ("    %s\n", _("Tell ssh to suppress warning and diagnostic messages [optional]"));
        printf (UT_WARN_CRIT);
        printf (UT_CONN_TIMEOUT, DEFAULT_SOCKET_TIMEOUT);
        printf (UT_VERBOSE);
        printf("\n");
  printf (" %s\n", _("The most common mode of use is to refer to a local identity file with"));
  printf (" %s\n", _("the '-i' option. In this mode, the identity pair should have a null"));
  printf (" %s\n", _("passphrase and the public key should be listed in the authorized_keys"));
  printf (" %s\n", _("file of the remote host. Usually the key will be restricted to running"));
  printf (" %s\n", _("only one command on the remote server. If the remote SSH server tracks"));
  printf (" %s\n", _("invocation arguments, the one remote program may be an agent that can"));
  printf (" %s\n", _("execute additional commands as proxy"));
  printf("\n");
  printf (" %s\n", _("To use passive mode, provide multiple '-C' options, and provide"));
  printf (" %s\n", _("all of -O, -s, and -n options (servicelist order must match '-C'options)"));
  printf ("\n");
  printf ("%s\n", _("Examples:"));
  printf (" %s\n", "$ check_by_ssh -H localhost -n lh -s c1:c2:c3 -C uptime -C uptime -C uptime -O /tmp/foo");
  printf (" %s\n", "$ cat /tmp/foo");
  printf (" %s\n", "[1080933700] PROCESS_SERVICE_CHECK_RESULT;flint;c1;0; up 2 days");
  printf (" %s\n", "[1080933700] PROCESS_SERVICE_CHECK_RESULT;flint;c2;0; up 2 days");
  printf (" %s\n", "[1080933700] PROCESS_SERVICE_CHECK_RESULT;flint;c3;0; up 2 days");

        printf(UT_SUPPORT);
}



void
print_usage (void)
{
        printf ("%s\n", _("Usage:"));
        printf (" %s -H <host> -C <command> [-fqv] [-1|-2] [-4|-6]\n"
                "       [-S [lines]] [-E [lines]] [-t timeout] [-i identity]\n"
                "       [-l user] [-n name] [-s servicelist] [-O outputfile]\n"
                "       [-p port] [-z] [-o ssh-option] [-F configfile]\n",
                progname);
}