glenux/igmpgen
1
0
Fork 0
Code Issues 5 Pull requests Projects 1 Releases Packages Wiki Activity

feat: implement basic packet creation

Browse source
This commit is contained in:
Glenn Y. Rolland 2009-09-07 22:54:51 +02:00
parent 7e60ac8b61
commit 8487dc951d
1 changed files with 64 additions and 12 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

76
src/igmpgen.c
View file

@ -21,6 +21,7 @@ struct igmp_extra {
{ 2, "query", 0x11, 1, "224.0.0.1", 0 },
{ 2, "report", 0x16, 1, "224.0.0.2", 1 },
{ 2, "leave", 0x17, 1, "224.0.0.2", 0 },
/* Note: end of list (please keep) */
{ 0, 0, 0, 0 },
};
@ -32,17 +33,22 @@ void usage(char *name)
int main(int argc, char **argv)
{
/* ip addresses */
u_int32_t ip_src = 0;
char *ip_src_str = NULL;
/* libnet stuff */
char neterr[LIBNET_ERRBUF_SIZE];
libnet_t *netcontext = NULL;
/* misc */
int c;
int c;
char *device = NULL;
u_int8_t igmp_version = 0;
char *cp = NULL;
int found = 0;
struct igmp_extra *pkt_ptr;
u_char igmp_type = 0;
u_char igmp_code = 0;
printf("IGMP packet generator\n\n");
printf("Parsing command line...\n");
@ -55,8 +61,27 @@ int main(int argc, char **argv)
device = optarg;
break;
case 't':
/* Packet version/type argument handling */
printf(" Packet version/type = [%s]\n", optarg);
if (!(cp = strrchr(optarg, '.'))) {
usage(argv[0]);
exit(1);
}
*cp++ = 0;
igmp_version = (u_short)atoi(cp);
pkt_ptr = g_igmp_pkts;
while (pkt_ptr->igmp_version || pkt_ptr->igmp_tag) {
if ((strcasecmp(pkt_ptr->igmp_tag, optarg) == 0)
&& (igmp_version == pkt_ptr->igmp_version)) {
found = 1;
igmp_type = pkt_ptr->igmp_type;
igmp_code = pkt_ptr->igmp_code;
break;
}
pkt_ptr++;
}
if (!found) {
usage(argv[0]);
exit(1);
}
break;
default:
usage(argv[0]);
@ -72,22 +97,49 @@ int main(int argc, char **argv)
printf("done\n");
/* Memory initialization */
printf("Initializing libnet context...");
printf("Initializing libnet context...\n");
netcontext = libnet_init(LIBNET_RAW4, device, neterr);
if (!netcontext){
fprintf(stderr, neterr);
if (!netcontext) {
fprintf(stderr, "%s\n", neterr);
exit(1);
}
libnet_clear_packet(netcontext);
if (!ip_src_str)
{
if (!ip_src_str) {
ip_src = libnet_get_ipaddr4(netcontext);
ip_src_str = libnet_addr2name4(ip_src, LIBNET_DONT_RESOLVE);
}
printf("done\n");
printf("Packet construction...\n");
/* Packet construction: IGMP */
printf(" Building IGMP content...\n");
libnet_ptag_t ptag;
ptag = libnet_build_igmp(
igmp_type, // IGMP type
igmp_code, // IGMP code
0, // checksum
0, // group address
NULL, // payload
0, // payload size
netcontext, // libnet context
0 // ptag
);
if (ptag == -1) {
fprintf(stderr, "Error building IGMP header: %s\n", libnet_geterror(netcontext));
libnet_destroy(netcontext);
exit(EXIT_FAILURE);
}
printf(" done\n");
/* Send packet */
if (libnet_write(netcontext) == -1) {
fprintf(stderr, "Error sending packet: %s\n", libnet_geterror(netcontext));
} else {
printf("Packet sent successfully.\n");
}
/* Clean up and exit */
libnet_destroy(netcontext);
return 0;
}