/******************************************************************************/
/* */
/* Copyright (c) International Business Machines Corp., 2006 */
/* */
/* 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */
/* */
/******************************************************************************/
/*
* File:
* ns-igmp_querier.c
*
* Description:
* This utiltity sends IGMP queries.
* (General Query, Multicast Address Specific Query
* or Multicast Address and Source Specific Query)
*
* Author:
* Mitsuru Chinen <mitch@jp.ibm.com>
*
* History:
* Apr 24 2006 - Created (Mitsuru Chinen)
*---------------------------------------------------------------------------*/
/*
* Header Files
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <netdb.h>
#include <signal.h>
#include <time.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <net/if.h>
#include <netinet/in.h>
#include <netinet/igmp.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <sys/types.h>
#include "ns-mcast.h"
#include "ns-traffic.h"
/*
* Structure Definitions
*/
struct igmp_info {
uint32_t ifindex;
struct igmpv3_query *query;
double timeout;
struct timespec interval;
};
/*
* Gloval variables
*/
char *program_name; /* program name */
struct sigaction handler; /* Behavior for a signal */
int catch_sighup; /* When catch the SIGHUP, set to non-zero */
/*
* Function: usage()
*
* Descripton:
* Print the usage of this program. Then, terminate this program with
* the specified exit value.
*
* Argument:
* exit_value: exit value
*
* Return value:
* This function does not return.
*/
void usage(char *program_name, int exit_value)
{
FILE *stream = stdout; /* stream where the usage is output */
if (exit_value == EXIT_FAILURE)
stream = stderr;
fprintf(stream, "%s [OPTION]\n"
"\t-I ifname\tname of listening interface\n"
"\t-m addr\tmulticast address\n"
"\t-s addrs\tcomma separated array of Source Addresses\n"
"\t-r value\tMax Resp Code\n"
"\t-i value\tinterval [nanosec]\n"
"\t-t value\ttimeout [sec]\n"
"\t-o\t\tsend only one query\n"
"\t-b\t\twork in the background\n"
"\t-d\t\tdisplay debug informations\n"
"\t-h\t\tdisplay this usage\n", program_name);
exit(exit_value);
}
/*
* Function: set_signal_flag()
*
* Description:
* This function sets global variables accordig to signal
*
* Argument:
* type: type of signal
*
* Return value:
* None
*/
void set_signal_flag(int type)
{
if (debug)
fprintf(stderr, "Catch signal. type is %d\n", type);
switch (type) {
case SIGHUP:
catch_sighup = 1;
handler.sa_handler = SIG_IGN;
if (sigaction(type, &handler, NULL) < 0)
fatal_error("sigaction()");
break;
default:
fprintf(stderr, "Unexpected signal (%d) is caught\n", type);
exit(EXIT_FAILURE);
}
}
/*
* Function: create_query()
*
* Description:
* This function create a igmpv3 query information.
* This function allocates memory to store the information.
*
* Argument:
* code: Max Resp Code
* maddr: multicast address
* saddrs: comma separated array of the source addresses
*
* Return value:
* pointer to allocated igmpv3_query structure
*/
struct igmpv3_query *create_query(uint8_t code, char *maddr, char *saddrs)
{
struct igmpv3_query *query; /* pointer to igmpv3_query structure */
uint16_t numsrc; /* number of source address */
size_t query_size; /* size of igmpv3_query */
struct in_addr ip;
uint32_t idx;
char *sp, *ep;
/* calculate the number of source address */
if (saddrs == NULL) {
numsrc = 0;
} else {
numsrc = 1;
for (sp = saddrs; *sp != '\0'; sp++)
if (*sp == ',')
numsrc++;
}
if (debug)
fprintf(stderr, "number of source address is %u\n", numsrc);
/* allocate memory for igmpv3_query structure */
query_size = MY_IGMPV3_QUERY_SIZE(numsrc);
query = (struct igmpv3_query *)calloc(1, query_size);
if (query == NULL)
fatal_error("calloc()");
/* substitute paramaters */
query->type = IGMP_HOST_MEMBERSHIP_QUERY;
query->code = code;
query->csum = 0; /* Calculate later */
query->resv = 0;
query->suppress = 0;
query->qrv = 0;
query->qqic = 0;
query->nsrcs = htons(numsrc);
/* substitute multicast address */
if (maddr == NULL) {
query->group = htonl(INADDR_ANY);
} else {
if (inet_pton(AF_INET, maddr, &ip) <= 0) {
fprintf(stderr,
"multicast address is something wrong\n");
return NULL;
}
query->group = ip.s_addr;
}
/* substitute source addresses */
sp = saddrs;
for (idx = 0; idx < numsrc; idx++) {
ep = strchr(sp, ',');
if (ep != NULL)
*ep = '\0';
if (debug)
fprintf(stderr, "source address[%u]: %s\n", idx, sp);
if (inet_pton(AF_INET, sp, &ip) <= 0) {
fprintf(stderr,
"source address list is something wrong\n");
return NULL;
}
query->srcs[idx] = ip.s_addr;
sp = ep + 1;
}
/* Calculate checksum */
query->csum = calc_checksum((u_int16_t *) query, query_size);
return query;
}
/*
* Function: parse_options()
*
* Description:
* This function parse the options
*
* Argument:
* argc: the number of argument
* argv: arguments
* info_p: pointer to data of querier information
* bg_p: pointer to the flag of working in backgrond
*
* Return value:
* None
*/
void parse_options(int argc, char *argv[], struct igmp_info *info_p, int *bg_p)
{
int optc; /* option */
unsigned long opt_ul; /* option value in unsigned long */
double opt_d; /* option value in double */
uint8_t max_resp; /* Max Resp Code */
char *maddr; /* multicast address */
char *saddrs; /* comma separated array of source addresses */
max_resp = IGMP_MAX_HOST_REPORT_DELAY;
maddr = NULL;
saddrs = NULL;
while ((optc = getopt(argc, argv, "I:m:s:r:t:i:obdh")) != EOF) {
switch (optc) {
case 'I':
info_p->ifindex = if_nametoindex(optarg);
if (info_p->ifindex == 0) {
fprintf(stderr,
"specified interface is incorrect\n");
usage(program_name, EXIT_FAILURE);
}
break;
case 'm':
maddr = strdup(optarg);
if (maddr == NULL)
fatal_error("strdup()");
break;
case 's':
saddrs = strdup(optarg);
if (saddrs == NULL)
fatal_error("strdup()");
break;
case 'r':
opt_ul = strtoul(optarg, NULL, 0);
if (opt_ul > 255) {
fprintf(stderr,
"Max Resp Code should be less then 256\n");
usage(program_name, EXIT_FAILURE);
}
max_resp = opt_ul;
break;
case 't':
opt_d = strtod(optarg, NULL);
if (opt_d < 0.0) {
fprintf(stderr,
"Timeout should be positive value\n");
usage(program_name, EXIT_FAILURE);
}
info_p->timeout = opt_d;
break;
case 'i':
if (strtotimespec(optarg, &info_p->interval)) {
fprintf(stderr,
"Interval is something wrong\n");
usage(program_name, EXIT_FAILURE);
}
break;
case 'o':
info_p->timeout = -1.0;
break;
case 'b':
*bg_p = 1;
break;
case 'd':
debug = 1;
break;
case 'h':
usage(program_name, EXIT_SUCCESS);
break;
default:
usage(program_name, EXIT_FAILURE);
}
}
if (info_p->ifindex == 0) {
fprintf(stderr, "specified interface seems incorrect\n");
usage(program_name, EXIT_FAILURE);
}
if ((info_p->query = create_query(max_resp, maddr, saddrs)) == NULL)
usage(program_name, EXIT_FAILURE);
free(maddr);
free(saddrs);
}
/*
* Function: create_socket()
*
* Description:
* This function creates a socket to send
*
* Argument:
* info_p: pointer to data of igmp query information
*
* Return value:
* file descriptor referencing the socket
*/
int create_socket(struct igmp_info *info_p)
{
int sd; /* socket file descriptor */
int on;
unsigned char opt[4] = { 0x94, 0x04, 0x00, 0x00 }; /* Router Alert */
struct ip_mreqn mcast_req, *req_p = &mcast_req;
/* Create a socket */
sd = socket(AF_INET, SOCK_RAW, IPPROTO_IGMP);
if (sd < 0)
fatal_error("socket()");
/* Enable to reuse the socket */
on = 1;
if (setsockopt(sd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(int)))
fatal_error("setsockopt(): enable to reuse the socket");
/* Add router alert option */
if (setsockopt(sd, IPPROTO_IP, IP_OPTIONS, opt, sizeof(opt)))
fatal_error("setsockopt(): socket options");
/* Specify the interface for outgoing datagrams */
req_p->imr_multiaddr.s_addr = info_p->query->group;
req_p->imr_address.s_addr = htonl(INADDR_ANY);
req_p->imr_ifindex = info_p->ifindex;
if (setsockopt(sd, IPPROTO_IP, IP_MULTICAST_IF,
req_p, sizeof(struct ip_mreqn))) {
fatal_error("setsockopt(): specify the interface");
}
return sd;
}
/*
* Function: send_query()
*
* Description:
* This function sends IGMP query
*
* Argument:
* info_p: pointer to data of igmp query information
*
* Return value:
* None
*/
void send_query(struct igmp_info *info_p)
{
int sd;
int retval;
double start_time;
struct sockaddr_in to;
size_t query_size;
/* Set singal hander for SIGHUP */
handler.sa_handler = set_signal_flag;
handler.sa_flags = 0;
if (sigfillset(&handler.sa_mask) < 0)
fatal_error("sigfillset()");
if (sigaction(SIGHUP, &handler, NULL) < 0)
fatal_error("sigaction()");
/* Specify multicast address to send */
to.sin_family = AF_INET;
to.sin_port = IPPROTO_IGMP;
if (info_p->query->group == htonl(INADDR_ANY))
to.sin_addr.s_addr = IGMP_ALL_HOSTS;
else
to.sin_addr.s_addr = info_p->query->group;
/* Create a socket */
sd = create_socket(info_p);
/* loop for sending queries */
start_time = time(NULL);
query_size = MY_IGMPV3_QUERY_SIZE(ntohs(info_p->query->nsrcs));
if (debug)
fprintf(stderr, "query size is %zu\n", query_size);
for (;;) {
retval = sendto(sd, info_p->query, query_size, 0,
(struct sockaddr *)&to,
sizeof(struct sockaddr_in));
if (retval != query_size) {
if (catch_sighup)
break;
else
fatal_error("sendto()");
}
/* Check timeout:
If timeout value is negative only send one datagram */
if (info_p->timeout)
if (info_p->timeout < difftime(time(NULL), start_time))
break;
/* Wait in specified interval */
nanosleep(&info_p->interval, NULL);
/* catch SIGHUP */
if (catch_sighup)
break;
}
close(sd);
}
/*
*
* Function: main()
*
*/
int main(int argc, char *argv[])
{
struct igmp_info mcast_rcv;
int background = 0;
debug = 0;
program_name = strdup(argv[0]);
memset(&mcast_rcv, '\0', sizeof(struct igmp_info));
parse_options(argc, argv, &mcast_rcv, &background);
if (background) /* Work in the background */
if (daemon(0, 0) < 0)
fatal_error("daemon()");
send_query(&mcast_rcv);
exit(EXIT_SUCCESS);
}