New "-m, --mac" option which allows for specifying the MAC address to

[nagiosplug.git] / plugins-root / check_dhcp.c

diff --git a/plugins-root/check_dhcp.c b/plugins-root/check_dhcp.c
index 904d43ef8e4f29225403694fd0827a16a77f92c4..a0f150fbf281b8809eff8adc5f060ce80531a27c 100644 (file)
--- a/plugins-root/check_dhcp.c
+++ b/plugins-root/check_dhcp.c
@@ -50,6 +50,7 @@ const char *email = "nagiosplug-devel@lists.sourceforge.net";
 #include "netutils.h"
 #include "utils.h"
 
+#include <ctype.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -211,6 +212,7 @@ u_int8_t unicast = 0;        /* unicast mode: mimic a DHCP relay */
 struct in_addr my_ip;        /* our address (required for relay) */
 struct in_addr dhcp_ip;      /* server to query (if in unicast mode) */
 unsigned char client_hardware_address[MAX_DHCP_CHADDR_LENGTH]="";
+unsigned char *user_specified_mac=NULL;
 
 char network_interface_name[IFNAMSIZ]="eth0";
 
@@ -241,6 +243,8 @@ int validate_arguments(void);
 void print_usage(void);
 void print_help(void);
 
+unsigned char *mac_aton(const char *);
+void print_hardware_address(const unsigned char *);
 int get_hardware_address(int,char *);
 int get_ip_address(int,char *);
 
@@ -279,7 +283,10 @@ int main(int argc, char **argv){
        dhcp_socket=create_dhcp_socket();
 
        /* get hardware address of client machine */
-       get_hardware_address(dhcp_socket,network_interface_name);
+       if(user_specified_mac!=NULL)
+               memcpy(client_hardware_address,user_specified_mac,6);
+       else
+               get_hardware_address(dhcp_socket,network_interface_name);
 
        if(unicast) /* get IP address of client machine */
                get_ip_address(dhcp_socket,network_interface_name);
@@ -308,12 +315,11 @@ int main(int argc, char **argv){
 /* determines hardware address on client machine */
 int get_hardware_address(int sock,char *interface_name){
 
-       int i;
-
 #if defined(__linux__)
        struct ifreq ifr;
 
-       strncpy((char *)&ifr.ifr_name,interface_name,sizeof(ifr.ifr_name));
+       strncpy((char *)&ifr.ifr_name,interface_name,sizeof(ifr.ifr_name)-1);
+       ifr.ifr_name[sizeof(ifr.ifr_name)-1]='\0';
        
        /* try and grab hardware address of requested interface */
        if(ioctl(sock,SIOCGIFHWADDR,&ifr)<0){
@@ -403,16 +409,12 @@ int get_hardware_address(int sock,char *interface_name){
                                                /* Kompf 2000-2003 */
 
 #else
-       printf(_("Error: can't get MAC address for this architecture.\n"));
+       printf(_("Error: can't get MAC address for this architecture.  Use the --mac option.\n"));
        exit(STATE_UNKNOWN);
 #endif
 
-       if(verbose){ 
-               printf(_("Hardware address: "));
-               for (i=0; i<6; ++i)
-                       printf("%2.2x", client_hardware_address[i]);
-               printf( "\n");
-               }
+       if(verbose)
+               print_hardware_address(client_hardware_address);
 
        return OK;
         }
@@ -773,14 +775,16 @@ int create_dhcp_socket(void){
 
        /* bind socket to interface */
 #if defined(__linux__)
-       strncpy(interface.ifr_ifrn.ifrn_name,network_interface_name,IFNAMSIZ);
+       strncpy(interface.ifr_ifrn.ifrn_name,network_interface_name,IFNAMSIZ-1);
+       interface.ifr_ifrn.ifrn_name[IFNAMSIZ-1]='\0';
        if(setsockopt(sock,SOL_SOCKET,SO_BINDTODEVICE,(char *)&interface,sizeof(interface))<0){
                printf(_("Error: Could not bind socket to interface %s.  Check your privileges...\n"),network_interface_name);
                exit(STATE_UNKNOWN);
                }
 
 #else
-       strncpy(interface.ifr_name,network_interface_name,IFNAMSIZ);
+       strncpy(interface.ifr_name,network_interface_name,IFNAMSIZ-1);
+       interface.ifr_name[IFNAMSIZ-1]='\0';
 #endif
 
         /* bind the socket */
@@ -1094,6 +1098,7 @@ int call_getopt(int argc, char **argv){
                {"requestedip",    required_argument,0,'r'},
                {"timeout",        required_argument,0,'t'},
                {"interface",      required_argument,0,'i'},
+               {"mac",            required_argument,0,'m'},
                {"unicast",        no_argument,      0,'u'},
                {"verbose",        no_argument,      0,'v'},
                {"version",        no_argument,      0,'V'},
@@ -1102,7 +1107,7 @@ int call_getopt(int argc, char **argv){
        };
 
        while(1){
-               c=getopt_long(argc,argv,"+hVvt:s:r:t:i:u",long_options,&option_index);
+               c=getopt_long(argc,argv,"+hVvt:s:r:t:i:m:u",long_options,&option_index);
 
                i++;
 
@@ -1159,6 +1164,15 @@ int call_getopt(int argc, char **argv){
                        */
                        break;
 
+               case 'm': /* MAC address */
+
+                       if((user_specified_mac=mac_aton(optarg)) == NULL)
+                               usage("Cannot parse MAC address.\n");
+                       if(verbose)
+                               print_hardware_address(user_specified_mac);
+
+                       break;
+
                case 'i': /* interface name */
 
                        strncpy(network_interface_name,optarg,sizeof(network_interface_name)-1);
@@ -1338,6 +1352,39 @@ long mac_addr_dlpi( const char *dev, int unit, u_char  *addr){
 #endif
 
 
+/* parse MAC address string, return 6 bytes (unterminated) or NULL */
+unsigned char *mac_aton(const char *string){
+       static unsigned char result[6];
+       char tmp[3];
+       unsigned i, j;
+
+       for(i=0, j=0; string[i] != '\0' && j < sizeof(result); i++){
+               /* ignore ':' and any other non-hex character */
+               if(!isxdigit(string[i]) || !isxdigit(string[i+1]))
+                       continue;
+               tmp[0]=string[i];
+               tmp[1]=string[i+1];
+               tmp[2]='\0';
+               result[j]=strtol(tmp,(char **)NULL,16);
+               i++;
+               j++;
+               }
+
+       return (j==6) ? result : NULL;
+       }
+
+
+void print_hardware_address(const unsigned char *address){
+       int i;
+
+       printf(_("Hardware address: "));
+       for (i=0; i<5; i++)
+               printf("%2.2x:", address[i]);
+       printf("%2.2x", address[i]);
+       putchar('\n');
+       }
+
+
 /* print usage help */
 void print_help(void){
 
@@ -1364,6 +1411,8 @@ void print_help(void){
   printf ("    %s\n", _("Seconds to wait for DHCPOFFER before timeout occurs"));
   printf (" %s\n", "-i, --interface=STRING");
   printf ("    %s\n", _("Interface to to use for listening (i.e. eth0)"));
+  printf (" %s\n", "-m, --mac=STRING");
+  printf ("    %s\n", _("MAC address to use in the DHCP request"));
   printf (" %s\n", "-u, --unicast");
   printf ("    %s\n", _("Unicast testing: mimic a DHCP relay, requires -s"));
 
@@ -1376,7 +1425,7 @@ print_usage(void){
        
   printf (_("Usage:"));
   printf (" %s [-v] [-u] [-s serverip] [-r requestedip] [-t timeout]\n",progname);
-  printf ("                  [-i interface]\n");
+  printf ("                  [-i interface] [-m mac]\n");
   
        return;
        }