diff options
| -rw-r--r-- | NEWS | 2 | ||||
| -rw-r--r-- | THANKS.in | 1 | ||||
| -rw-r--r-- | configure.in | 3 | ||||
| -rw-r--r-- | plugins-root/check_dhcp.c | 84 |
4 files changed, 80 insertions, 10 deletions
@@ -9,6 +9,8 @@ This file documents the major additions and syntax changes between releases. Check_disk now calls stat() on all filesystems to check. (Old: only the ones selected using -p) A meaningful error message (eg "Stale NFS Handle") is printed if stat fails. Check_disk's --help now prints some examples for the new features introduced in 1.4.8 + New check_dhcp -u/--unicast option for emulating a DHCP relay in order + to check DHCP servers on remote networks 1.4.9 4th June 2006 Inclusion of contrib/check_cluster2 as check_cluster with some improvements @@ -223,3 +223,4 @@ Daniel Bimschas Aurelien Bompard Christoph Schell Andrew Elwell +Heiti Ernits diff --git a/configure.in b/configure.in index 5b5b983b..86f37809 100644 --- a/configure.in +++ b/configure.in @@ -1450,6 +1450,9 @@ elif test -f ../plugins/check_nt.c ; then fi +dnl used in check_dhcp +AC_CHECK_HEADERS(sys/sockio.h) + case $host in *bsd*) AC_DEFINE(__bsd__,1,[bsd specific code in check_dhcp.c]) diff --git a/plugins-root/check_dhcp.c b/plugins-root/check_dhcp.c index 7cb2d300..a1d04c18 100644 --- a/plugins-root/check_dhcp.c +++ b/plugins-root/check_dhcp.c @@ -33,6 +33,12 @@ * * $Id$ * +* ------------------------------------------------------------------------ +* Unicast mode was originally implemented by Heiti of Boras Kommun with +* general improvements as well as usability fixes and "forward"-porting by +* Andreas Ericsson of OP5 AB. +* ------------------------------------------------------------------------ +* *****************************************************************************/ const char *progname = "check_dhcp"; @@ -59,6 +65,9 @@ const char *email = "nagiosplug-devel@lists.sourceforge.net"; #include <netinet/in.h> #include <net/if.h> #include <arpa/inet.h> +#if HAVE_SYS_SOCKIO_H +#include <sys/sockio.h> +#endif #if defined( __linux__ ) @@ -190,6 +199,7 @@ typedef struct requested_server_struct{ #define DHCP_INFINITE_TIME 0xFFFFFFFF #define DHCP_BROADCAST_FLAG 32768 +#define DHCP_UNICAST_FLAG 0 #define DHCP_SERVER_PORT 67 #define DHCP_CLIENT_PORT 68 @@ -197,6 +207,9 @@ typedef struct requested_server_struct{ #define ETHERNET_HARDWARE_ADDRESS 1 /* used in htype field of dhcp packet */ #define ETHERNET_HARDWARE_ADDRESS_LENGTH 6 /* length of Ethernet hardware addresses */ +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]=""; char network_interface_name[IFNAMSIZ]="eth0"; @@ -229,6 +242,7 @@ void print_usage(void); void print_help(void); int get_hardware_address(int,char *); +int get_ip_address(int,char *); int send_dhcp_discover(int); int get_dhcp_offer(int); @@ -267,6 +281,9 @@ int main(int argc, char **argv){ /* get hardware address of client machine */ get_hardware_address(dhcp_socket,network_interface_name); + if(unicast) /* get IP address of client machine */ + get_ip_address(dhcp_socket,network_interface_name); + /* send DHCPDISCOVER packet */ send_dhcp_discover(dhcp_socket); @@ -400,6 +417,32 @@ int get_hardware_address(int sock,char *interface_name){ return OK; } +/* determines IP address of the client interface */ +int get_ip_address(int sock,char *interface_name){ +#if defined(SIOCGIFADDR) + struct ifreq ifr; + + strncpy((char *)&ifr.ifr_name,interface_name,sizeof(ifr.ifr_name)-1); + ifr.ifr_name[sizeof(ifr.ifr_name)-1]='\0'; + + if(ioctl(sock,SIOCGIFADDR,&ifr)<0){ + printf(_("Error: Cannot determine IP address of interface %s\n"), + interface_name); + exit(STATE_UNKNOWN); + } + + my_ip=((struct sockaddr_in *)&ifr.ifr_addr)->sin_addr; + +#else + printf(_("Error: Cannot get interface IP address on this platform.\n")); + exit(STATE_UNKNOWN); +#endif + + if(verbose) + printf(_("Pretending to be relay client %s\n"),inet_ntoa(my_ip)); + + return OK; + } /* sends a DHCPDISCOVER broadcast message in an attempt to find DHCP servers */ int send_dhcp_discover(int sock){ @@ -421,8 +464,6 @@ int send_dhcp_discover(int sock){ /* length of our hardware address */ discover_packet.hlen=ETHERNET_HARDWARE_ADDRESS_LENGTH; - discover_packet.hops=0; - /* transaction id is supposed to be random */ srand(time(NULL)); packet_xid=random(); @@ -435,8 +476,11 @@ int send_dhcp_discover(int sock){ /*discover_packet.secs=htons(65535);*/ discover_packet.secs=0xFF; - /* tell server it should broadcast its response */ - discover_packet.flags=htons(DHCP_BROADCAST_FLAG); + /* + * server needs to know if it should broadcast or unicast its response: + * 0x8000L == 32768 == 1 << 15 == broadcast, 0 == unicast + */ + discover_packet.flags = unicast ? 0 : htons(DHCP_BROADCAST_FLAG); /* our hardware address */ memcpy(discover_packet.chaddr,client_hardware_address,ETHERNET_HARDWARE_ADDRESS_LENGTH); @@ -462,10 +506,17 @@ int send_dhcp_discover(int sock){ } discover_packet.options[opts++]=DHCP_OPTION_END; + /* unicast fields */ + if(unicast) + discover_packet.giaddr.s_addr = my_ip.s_addr; + + /* see RFC 1542, 4.1.1 */ + discover_packet.hops = unicast ? 1 : 0; + /* send the DHCPDISCOVER packet to broadcast address */ sockaddr_broadcast.sin_family=AF_INET; sockaddr_broadcast.sin_port=htons(DHCP_SERVER_PORT); - sockaddr_broadcast.sin_addr.s_addr=INADDR_BROADCAST; + sockaddr_broadcast.sin_addr.s_addr = unicast ? dhcp_ip.s_addr : INADDR_BROADCAST; bzero(&sockaddr_broadcast.sin_zero,sizeof(sockaddr_broadcast.sin_zero)); @@ -685,8 +736,9 @@ int create_dhcp_socket(void){ /* Set up the address we're going to bind to. */ bzero(&myname,sizeof(myname)); myname.sin_family=AF_INET; - myname.sin_port=htons(DHCP_CLIENT_PORT); - myname.sin_addr.s_addr=INADDR_ANY; /* listen on any address */ + /* listen to DHCP server port if we're in unicast mode */ + myname.sin_port = htons(unicast ? DHCP_SERVER_PORT : DHCP_CLIENT_PORT); + myname.sin_addr.s_addr = unicast ? my_ip.s_addr : INADDR_ANY; bzero(&myname.sin_zero,sizeof(myname.sin_zero)); /* create a socket for DHCP communications */ @@ -1035,6 +1087,7 @@ int call_getopt(int argc, char **argv){ {"requestedip", required_argument,0,'r'}, {"timeout", required_argument,0,'t'}, {"interface", required_argument,0,'i'}, + {"unicast", no_argument, 0,'u'}, {"verbose", no_argument, 0,'v'}, {"version", no_argument, 0,'V'}, {"help", no_argument, 0,'h'}, @@ -1042,7 +1095,7 @@ int call_getopt(int argc, char **argv){ }; while(1){ - c=getopt_long(argc,argv,"+hVvt:s:r:t:i:",long_options,&option_index); + c=getopt_long(argc,argv,"+hVvt:s:r:t:i:u",long_options,&option_index); i++; @@ -1063,8 +1116,12 @@ int call_getopt(int argc, char **argv){ switch(c){ case 's': /* DHCP server address */ - if(inet_aton(optarg,&ipaddress)) + if(inet_aton(optarg,&ipaddress)){ add_requested_server(ipaddress); + inet_aton(optarg, &dhcp_ip); + if (verbose) + printf("querying %s\n",inet_ntoa(dhcp_ip)); + } /* else usage("Invalid server IP address\n"); @@ -1102,6 +1159,10 @@ int call_getopt(int argc, char **argv){ break; + case 'u': /* unicast testing */ + unicast=1; + break; + case 'V': /* version */ print_revision(progname,revision); exit(STATE_OK); @@ -1296,6 +1357,8 @@ 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", "-u, --unicast"); + printf (" %s\n", _("Unicast testing: mimic a DHCP relay, requires -s")); return; } @@ -1305,7 +1368,8 @@ void print_usage(void){ printf (_("Usage:")); - printf ("%s [-s serverip] [-r requestedip] [-t timeout] [-i interface] [-v]\n",progname); + printf (" %s [-v] [-u] [-s serverip] [-r requestedip] [-t timeout]\n",progname); + printf (" [-i interface]\n"); return; } |