/****************************************************************************** * * Nagios check_ssh plugin * * License: GPL * Copyright (c) 1999-2006 nagios-plugins team * * Last Modified: $Date: 2006/10/19 23:53:28 $ * * Description: * * This file contains the check_ssh plugin * * * Try to connect to an SSH server at specified server and port * * * License Information: * * 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 2 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, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. * * $Id: check_ssh.c,v 1.30 2006/10/19 23:53:28 opensides Exp $ * ******************************************************************************/ const char *progname = "check_ssh"; const char *revision = "$Revision: 1.30 $"; const char *copyright = "2000-2006"; const char *email = "nagiosplug-devel@lists.sourceforge.net"; #include "common.h" #include "netutils.h" #include "utils.h" #ifndef MSG_DONTWAIT #define MSG_DONTWAIT 0 #endif #define SSH_DFL_PORT 22 #define BUFF_SZ 256 int port = -1; char *server_name = NULL; char *remote_version = NULL; int verbose = FALSE; int process_arguments (int, char **); int validate_arguments (void); void print_help (void); void print_usage (void); int ssh_connect (char *haddr, int hport, char *remote_version); int main (int argc, char **argv) { int result = STATE_UNKNOWN; setlocale (LC_ALL, ""); bindtextdomain (PACKAGE, LOCALEDIR); textdomain (PACKAGE); if (process_arguments (argc, argv) == ERROR) usage4 (_("Could not parse arguments")); /* initialize alarm signal handling */ signal (SIGALRM, socket_timeout_alarm_handler); alarm (socket_timeout); /* ssh_connect exits if error is found */ result = ssh_connect (server_name, port, remote_version); alarm (0); return (result); } /* process command-line arguments */ int process_arguments (int argc, char **argv) { int c; int option = 0; static struct option longopts[] = { {"help", no_argument, 0, 'h'}, {"version", no_argument, 0, 'V'}, {"host", required_argument, 0, 'H'}, {"port", required_argument, 0, 'p'}, {"use-ipv4", no_argument, 0, '4'}, {"use-ipv6", no_argument, 0, '6'}, {"timeout", required_argument, 0, 't'}, {"verbose", no_argument, 0, 'v'}, {"remote-version", required_argument, 0, 'r'}, {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, "+Vhv46t:r:H:p:", longopts, &option); if (c == -1 || c == EOF) break; switch (c) { case '?': /* help */ usage2 (_("Unknown argument"), optarg); case 'V': /* version */ print_revision (progname, revision); exit (STATE_OK); case 'h': /* help */ print_help (); exit (STATE_OK); case 'v': /* verbose */ verbose = TRUE; break; case 't': /* timeout period */ if (!is_integer (optarg)) usage2 (_("Timeout interval must be a positive integer"), optarg); else socket_timeout = atoi (optarg); break; case '4': address_family = AF_INET; break; case '6': #ifdef USE_IPV6 address_family = AF_INET6; #else usage4 (_("IPv6 support not available")); #endif break; case 'r': /* remote version */ remote_version = optarg; break; case 'H': /* host */ if (is_host (optarg) == FALSE) usage2 (_("Invalid hostname/address"), optarg); server_name = optarg; break; case 'p': /* port */ if (is_intpos (optarg)) { port = atoi (optarg); } else { usage2 (_("Port number must be a positive integer"), optarg); } } } c = optind; if (server_name == NULL && c < argc) { if (is_host (argv[c])) { server_name = argv[c++]; } } if (port == -1 && c < argc) { if (is_intpos (argv[c])) { port = atoi (argv[c++]); } else { print_usage (); exit (STATE_UNKNOWN); } } return validate_arguments (); } int validate_arguments (void) { if (server_name == NULL) return ERROR; if (port == -1) /* funky, but allows -p to override stray integer in args */ port = SSH_DFL_PORT; return OK; } /************************************************************************ * * Try to connect to SSH server at specified server and port * *-----------------------------------------------------------------------*/ int ssh_connect (char *haddr, int hport, char *remote_version) { int sd; int result; char *output = NULL; char *buffer = NULL; char *ssh_proto = NULL; char *ssh_server = NULL; char rev_no[20]; sscanf ("$Revision: 1.30 $", "$Revision: %[0123456789.]", rev_no); result = my_tcp_connect (haddr, hport, &sd); if (result != STATE_OK) return result; output = (char *) malloc (BUFF_SZ + 1); memset (output, 0, BUFF_SZ + 1); recv (sd, output, BUFF_SZ, 0); if (strncmp (output, "SSH", 3)) { printf (_("Server answer: %s"), output); exit (STATE_CRITICAL); } else { strip (output); if (verbose) printf ("%s\n", output); ssh_proto = output + 4; ssh_server = ssh_proto + strspn (ssh_proto, "-0123456789. "); ssh_proto[strspn (ssh_proto, "0123456789. ")] = 0; asprintf (&buffer, "SSH-%s-check_ssh_%s\r\n", ssh_proto, rev_no); send (sd, buffer, strlen (buffer), MSG_DONTWAIT); if (verbose) printf ("%s\n", buffer); if (remote_version && strcmp(remote_version, ssh_server)) { printf (_("SSH WARNING - %s (protocol %s) version mismatch, expected '%s'\n"), ssh_server, ssh_proto, remote_version); exit (STATE_WARNING); } printf (_("SSH OK - %s (protocol %s)\n"), ssh_server, ssh_proto); close(sd); exit (STATE_OK); } } void print_help (void) { char *myport; asprintf (&myport, "%d", SSH_DFL_PORT); print_revision (progname, revision); printf ("Copyright (c) 1999 Remi Paulmier \n"); printf (COPYRIGHT, copyright, email); printf ("%s\n", _("Try to connect to an SSH server at specified server and port")); printf ("\n\n"); print_usage (); printf (_(UT_HELP_VRSN)); printf (_(UT_HOST_PORT), 'p', myport); printf (_(UT_IPv46)); printf (_(UT_TIMEOUT), DEFAULT_SOCKET_TIMEOUT); printf (" %s\n", "-r, --remote-version=STRING"); printf (" %s\n", _("Warn if string doesn't match expected server version (ex: OpenSSH_3.9p1)")); printf (_(UT_VERBOSE)); printf (_(UT_SUPPORT)); } void print_usage (void) { printf (_("Usage:")); printf ("%s [-46] [-t ] [-r ] [-p ] \n", progname); }