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-rw-r--r--contrib/check_logins.c351
1 files changed, 351 insertions, 0 deletions
diff --git a/contrib/check_logins.c b/contrib/check_logins.c
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index 00000000..fa3ed177
--- /dev/null
+++ b/contrib/check_logins.c
@@ -0,0 +1,351 @@
+/*=================================
+ * check_logins - Nagios plugin
+ * Copyright (C) 2003 Dag Robøle
+ *
+ * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * Authors email: drobole@broadpark.no
+ */
+//=================================
+#include <sys/types.h>
+#include <signal.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+
+#include "config.h"
+#include "common.h"
+#include "utils.h"
+#include "popen.h"
+//=================================
+#define REVISION "$Revision$"
+#define COPYRIGHT "2003"
+#define AUTHOR "Dag Robole"
+#define EMAIL "drobole@broadpark.no"
+#define SUMMARY "Check for multiple user logins"
+
+#define check(func, errmsg) { if((func) == -1) die(STATE_UNKNOWN, errmsg); }
+#define checkz(func, errmsg) { if(!(func)) die(STATE_UNKNOWN, errmsg); }
+//=================================
+typedef struct USERNODE_TYP {
+ char *name;
+ char *host;
+ struct USERNODE_TYP* next;
+} USERNODE;
+//=================================
+char *progname = NULL;
+USERNODE *userlist = NULL, *adminlist = NULL;
+int warning_limit = 0, critical_limit = 0;
+
+void print_usage();
+void print_help();
+void process_arguments(int argc, char* *argv);
+void parse_wholine(const char *line, char *name, char *host);
+void node_create(USERNODE* *node, const char *name, const char *host);
+void node_free(USERNODE* *node);
+USERNODE* list_insert_sort_uniq(USERNODE* *list, USERNODE* *node);
+void list_free(USERNODE* *list);
+void cleanup();
+//=================================
+int main(int argc, char* *argv)
+{
+ FILE *who;
+ USERNODE *newnode, *nptra, *nptrb;
+ char buffer[BUFSIZ], username[BUFSIZ], hostname[BUFSIZ], *cptra, *cptrb;
+ char max_login_name[BUFSIZ], currname[BUFSIZ];
+ int max_login_count = 0, counter = 0, skip;
+ void (*old_sig_alrm)();
+
+ progname = argv[0];
+ if(atexit(cleanup))
+ die(STATE_UNKNOWN, "atexit failed\n");
+
+ if((old_sig_alrm = signal((int)SIGALRM, timeout_alarm_handler)) == SIG_ERR)
+ die(STATE_UNKNOWN, "signal failed\n");
+ alarm(timeout_interval);
+
+ process_arguments(argc, argv);
+
+ checkz(who = spopen(PATH_TO_WHO), "spopen failed\n");
+
+ while(fgets(buffer, sizeof(buffer), who) != NULL) {
+ parse_wholine(buffer, username, hostname);
+ skip = 0;
+ nptra = adminlist;
+
+ while(nptra != NULL) {
+ if(!strcmp(nptra->name, username)) {
+ skip = 1;
+ break;
+ }
+ nptra = nptra->next;
+ }
+ if(!skip) {
+ node_create(&newnode, username, hostname);
+ if(!list_insert_sort_uniq(&userlist, &newnode))
+ node_free(&newnode);
+ }
+ }
+
+ check(spclose(who), "spclose failed\n");
+
+ if(userlist != NULL) {
+ nptra = userlist;
+ strcpy(currname, nptra->name);
+ strcpy(max_login_name, nptra->name);
+ max_login_count = 1;
+ while(nptra != NULL) {
+ if(!strcmp(currname, nptra->name))
+ ++counter;
+ else {
+ if(counter > max_login_count) {
+ max_login_count = counter;
+ strcpy(max_login_name, currname);
+ }
+ strcpy(currname, nptra->name);
+ counter = 1;
+ }
+ nptra = nptra->next;
+ }
+
+ if(counter > max_login_count) {
+ max_login_count = counter;
+ strcpy(max_login_name, currname);
+ }
+ }
+
+ if(signal((int)SIGALRM, old_sig_alrm) == SIG_ERR)
+ die(STATE_UNKNOWN, "signal failed\n");
+
+ if(max_login_count) {
+ if(critical_limit && max_login_count >= critical_limit) {
+ printf("CRITICAL - User %s has logged in from %d different hosts\n", max_login_name, max_login_count);
+ return STATE_CRITICAL;
+ }
+ else if(warning_limit && max_login_count >= warning_limit) {
+ printf("WARNING - User %s has logged in from %d different hosts\n", max_login_name, max_login_count);
+ return STATE_WARNING;
+ }
+ }
+
+ printf("OK - No users has exceeded the login limits\n");
+ return STATE_OK;
+}
+//=================================
+void print_usage()
+{
+ fprintf(stderr, "Usage: %s [ -hV ] [ -w limit ] [ -c limit ] [ -u username1, ... ,usernameN ]\n", progname);
+}
+//=================================
+void print_help()
+{
+ print_revision(progname, REVISION);
+ printf("Copyright (c) %s %s <%s>\n\n%s\n\n", COPYRIGHT, AUTHOR, EMAIL, SUMMARY);
+ print_usage();
+ printf("\nDescription:\n"
+ "\tThis plugin supports the w (warning) and c (critical) options indicating the upper limits\n"
+ "\tof logins allowed before a warning is given.\n"
+ "\tThe output from %s is the username and number of login sessions for the user\n"
+ "\twho has the most login sessions (from different hosts) running at a given point in time.\n"
+ "\tThe u (users) option takes a comma separated list of usernames that will be ignored\n"
+ "\twhile scannig users.\n"
+ "\nOptions:\n"
+ "\t-h | --help\n\t\tShow this help message and exit\n"
+ "\t-V | --version\n\t\tShow version description\n"
+ "\t-w | --warning=INTEGER\n\t\tSet warning limit for logins (minimum value is 2)\n"
+ "\t-c | --critical=INTEGER\n\t\tSet critical limit for logins (minimum value is 2)\n"
+ "\t-u | --users=STRING\n\t\tSet usernames to be ignored\n"
+ "\nExamples:\n\t%s -w 3 -c 5\n"
+ "\t%s -w 3 -c 5 -u root,guest,jcarmack\n\n", progname, progname, progname);
+}
+//=================================
+void process_arguments(int argc, char* *argv)
+{
+ USERNODE *newnode;
+ int optch;
+ char buffer[BUFSIZ], *cptra;
+ static struct option long_opts[] = {
+ {"help", no_argument, 0, 'h'},
+ {"version", no_argument, 0, 'V'},
+ {"warning", required_argument, 0, 'w'},
+ {"critical", required_argument, 0, 'c'},
+ {"users", required_argument, 0, 'u'},
+ {0, 0, 0, 0},
+ };
+
+ while((optch = getopt_long(argc, argv, "hVw:c:u:", long_opts, NULL)) != -1) {
+ switch(optch) {
+ case 'h':
+ print_help();
+ exit(STATE_OK);
+ break;
+ case 'V':
+ print_revision(progname, REVISION);
+ exit(STATE_OK);
+ break;
+ case 'w':
+ if(!is_numeric(optarg)) {
+ print_usage();
+ die(STATE_UNKNOWN, "invalid options\n");
+ }
+ warning_limit = atoi(optarg) > 2 ? atoi(optarg) : 2;
+ break;
+ case 'c':
+ if(!is_numeric(optarg)) {
+ print_usage();
+ die(STATE_UNKNOWN, "invalid options\n");
+ }
+ critical_limit = atoi(optarg) > 2 ? atoi(optarg) : 2;
+ break;
+ case 'u':
+ strcpy(buffer, optarg);
+ cptra = strtok(buffer, ",");
+ while(cptra != NULL) {
+ node_create(&newnode, cptra, "(adminhost)");
+ list_insert_sort_uniq(&adminlist, &newnode);
+ cptra = strtok(NULL, ",");
+ }
+ break;
+ default:
+ print_usage();
+ exit(STATE_UNKNOWN);
+ break;
+ }
+ }
+
+ if(argc > optind) {
+ print_usage();
+ die(STATE_UNKNOWN, "invalid options\n");
+ }
+
+ if(!warning_limit && !critical_limit) {
+ print_usage();
+ die(STATE_UNKNOWN, "you must provide a limit for this plugin\n");
+ }
+
+ if(critical_limit && warning_limit > critical_limit) {
+ print_usage();
+ die(STATE_UNKNOWN, "warning limit must be less or equal critical limit\n");
+ }
+}
+//=================================
+void parse_wholine(const char *line, char *name, char *host)
+{
+ char buffer[BUFSIZ], *cptra, *cptrb, *display;
+ strcpy(buffer, line);
+
+ cptra = buffer;
+ checkz(cptrb = (char*)strchr(buffer, ' '), "strchr failed\n");
+ strncpy(name, cptra, cptrb-cptra);
+ name[cptrb-cptra] = '\0';
+
+ if((cptra = strchr(buffer, '(')) != NULL) // hostname found in source arg...
+ {
+ if(cptra[1] == ':') // local host
+ strcpy(host, "(localhost)");
+ else // extern host
+ {
+ checkz(cptrb = strchr(cptra, ')'), "strchr failed\n");
+ cptrb++;
+ strncpy(host, cptra, cptrb-cptra);
+ host[cptrb-cptra] = '\0';
+ }
+ }
+ else // no hostname in source arg, look in line arg...
+ {
+ checkz(cptra = strtok(buffer, " \t\r\n"), "strtok failed\n");
+ checkz(cptra = strtok(NULL, " \t\r\n"), "strtok failed\n");
+ if(cptra[0] == ':') // local host
+ strcpy(host, "(localhost)");
+ else // extern host
+ sprintf(host, "(%s)", cptra);
+ }
+
+ if((cptra = strchr(host, ':')) != NULL) // remove display if any...
+ strcpy(cptra, ")");
+}
+//=================================
+void node_create(USERNODE* *node, const char *name, const char *host)
+{
+ checkz(*node = (USERNODE*)malloc(sizeof(USERNODE)), "malloc failed\n");
+ checkz((*node)->name = (char*)malloc(strlen(name)+1), "malloc failed\n");
+ checkz((*node)->host = (char*)malloc(strlen(host)+1), "malloc failed\n");
+ (*node)->next = NULL;
+ strcpy((*node)->name, name);
+ strcpy((*node)->host, host);
+}
+//=================================
+void node_free(USERNODE* *node)
+{
+ free((*node)->name);
+ free((*node)->host);
+ free(*node);
+ *node = NULL;
+}
+//=================================
+USERNODE* list_insert_sort_uniq(USERNODE* *list, USERNODE* *node)
+{
+ char n1[BUFSIZ], n2[BUFSIZ];
+ USERNODE *last_nptr = NULL, *nptr = *list;
+
+ if(*list == NULL)
+ return(*list = *node);
+ else {
+ sprintf(n1, "%s %s", (*node)->name, (*node)->host);
+ while(nptr != NULL) {
+ sprintf(n2, "%s %s", nptr->name, nptr->host);
+ if(!strcmp(n1, n2))
+ return NULL;
+ else if(strcmp(n1, n2) < 0) {
+ if(last_nptr) {
+ last_nptr->next = *node;
+ (*node)->next = nptr;
+ }
+ else {
+ (*node)->next = *list;
+ *list = *node;
+ }
+ break;
+ }
+ else {
+ last_nptr = nptr;
+ nptr = nptr->next;
+ }
+ }
+ if(nptr == NULL)
+ last_nptr->next = *node;
+ }
+ return *node;
+}
+//=================================
+void list_free(USERNODE* *list)
+{
+ USERNODE *doe, *nptr = *list;
+ while(nptr != NULL) {
+ doe = nptr;
+ nptr = nptr->next;
+ node_free(&doe);
+ }
+ *list = NULL;
+}
+//=================================
+void cleanup()
+{
+ list_free(&userlist);
+ list_free(&adminlist);
+}
+//=================================
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