1 files changed, 351 insertions, 0 deletions

diff --git a/contrib/check_logins.c b/contrib/check_logins.c
new file mode 100644
index 0000000..fa3ed17
--- /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);
+}
+//=================================