feat: add real igmp features

src/igmpgen.c

@@ -5,6 +5,8 @@
 #include <libnet.h>
 #include <netinet/igmp.h>
 
+#define IGMP_V3_MEMBERSHIP_REPORT 0x22
+
 /* Structure to represent IGMP extra information */
 struct igmp_extra {
     u_int8_t igmp_version;
@@ -21,80 +23,149 @@ 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 },
+    { 3, "report", 0x22, 1, "224.0.0.22", 0 },
+
     /* Note: end of list (please keep) */
     { 0, 0, 0, 0 },
 };
 
 void usage(char *name)
 {
-    fprintf(stderr, "usage: %s -i ethdevice -g group -t packet.version\n", name);
+    struct igmp_extra *pkt_ptr;
+    fprintf(stderr, "usage: %s -i ethdevice -g group -t packet.version [-s ip:port] [-d ip:port]\n", name);
+
+    pkt_ptr = g_igmp_pkts;
+    fprintf(stderr,"\nAvailable packet types:\n");
+    while(pkt_ptr->igmp_version || pkt_ptr->igmp_tag){
+        fprintf(stderr," - %s.%d\n", pkt_ptr->igmp_tag, pkt_ptr->igmp_version);
+        pkt_ptr++; 
+    }
 }
 
 int main(int argc, char **argv)
 {
     u_int32_t ip_src = 0;
+    u_int32_t ip_dst = 0;
+    u_int32_t igmp_group = 0;      
+    char *igmp_group_str = NULL;
     char *ip_src_str = NULL;
+    char *ip_dst_str = NULL;
+
+    /* ports */
+    u_short src_prt = 3141;
+    u_short dst_prt = 5926;   
+
+    /* igmp stuff */
+    u_char igmp_type = 0;
+    u_char igmp_code = 0;
+    u_int8_t igmp_version = 0;
+    int igmp_override;
+    struct igmp_extra *pkt_ptr;
+
+    int ip_src_test = 1;
+    int ip_dst_test = 1;
+    int igmp_group_test =1;
+
     /* libnet stuff */
     char neterr[LIBNET_ERRBUF_SIZE];
+    libnet_ptag_t ptag;
     libnet_t *netcontext = NULL;
 
     /* misc */
+    char *device = "eth0";
     int c;                      
-    char *device = NULL;
-    u_int8_t igmp_version = 0;
     char *cp = NULL; 
-    int found = 0;
+    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");
-    while((c = getopt(argc, argv, "i:t:g:")) != EOF)
+    while((c = getopt(argc, argv, "i:t:g:d:s:")) != EOF)
     {
         switch (c)
         {
             case 'i':
-                printf("  Net interface = [%s]\n", optarg);
+                printf("  Net interface = [%s]\n",optarg);
                 device = optarg;
                 break;
+
             case 't':
                 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) {
+                while(pkt_ptr->igmp_version || pkt_ptr->igmp_tag){
                     if ((strcasecmp(pkt_ptr->igmp_tag, optarg) == 0) 
-                        && (igmp_version == pkt_ptr->igmp_version)) {
+                            && (igmp_version == pkt_ptr->igmp_version)){
                         found = 1;
                         igmp_type = pkt_ptr->igmp_type;
                         igmp_code = pkt_ptr->igmp_code;
+                        ip_dst_str = pkt_ptr->igmp_dst;
+                        igmp_override = pkt_ptr->group_override_dst;
+
                         break;
                     }
                     pkt_ptr++; 
                 }
-                if (!found) {
+                if (found){
+                    printf("  Packet = [%s] version [%d]\n", pkt_ptr->igmp_tag, igmp_version);
+                } else {
                     usage(argv[0]);
                     exit(1);
                 }
                 break;
+
             case 'g':
                 // Group argument handling logic
                 printf("  Group = [%s]\n", optarg);
-            	igmp_group_str = optarg;
+                igmp_group_str = optarg;
                 break;
 
+            case 'n':
+                // delay between packets in sec
                 break;
+
+                /*
+                 *  We expect the input to be of the form `ip.ip.ip.ip.port`.  We
+                 *  point cp to the last dot of the IP address/port string and
+                 *  then seperate them with a NULL byte.  The optarg now points to
+                 *  just the IP address, and cp points to the port.
+                 */
+            case 'd':
+                if ((cp = strrchr(optarg, ':')))
+                {
+                    *cp++ = 0;
+                    dst_prt = (u_short)atoi(cp);
+                } else {
+                    dst_prt = 0;
+                }
+                ip_dst_str = strdup(optarg);
+                printf("  Destination = ip [%s] port [%d]\n", ip_dst_str, dst_prt);
+                break;
+
+            case 's':
+                if ((cp = strrchr(optarg, ':')))
+                {
+                    *cp++ = 0;
+                    src_prt = (u_short)atoi(cp);
+                } else {
+                    src_prt = 0;
+                }
+                ip_src_str = strdup(optarg);
+                printf("  Source = ip [%s] port [%d]\n", ip_src_str, src_prt);
+                break;
+
             default:
                 usage(argv[0]);
                 exit(1);
         }
     }
-    if (!device)
+    if (!igmp_group_str || !device)
     {
         usage(argv[0]);
         exit(EXIT_FAILURE);
@@ -120,7 +191,6 @@ int main(int argc, char **argv)
 
     /* Packet construction: IGMP */
     printf("  Building IGMP content...\n");
-    libnet_ptag_t ptag;
     ptag = libnet_build_igmp(
         igmp_type,        // IGMP type
         igmp_code,        // IGMP code
@@ -146,6 +216,150 @@ int main(int argc, char **argv)
         printf("Packet sent successfully.\n");
     }
 
+    printf("Packet construction...\n");
+
+    /*
+     *  Packet construction : IGMP
+     */
+    printf("  Building IGMP content...\n");
+
+    // Override dest with group info when needed
+    if (igmp_override) {
+        ip_dst_str = igmp_group_str;
+    }
+
+    switch ( igmp_type ) {
+        case 0x11: // IGMP_MEMBERSHIP_QUERY
+            if (igmp_version == 2){
+                // group specific
+            } else if (igmp_version == 1) {
+                // general
+                igmp_group = 0;
+                igmp_group_str = "0.0.0.0";
+                igmp_group_test = 0;
+            }
+            // DST = 224.0.0.1
+            //igmp_group = 0;
+            //igmp_group_test = 0;
+            break;
+        case 0x12: //
+        default:
+            break;
+    }
+
+    if (ip_src_test
+            && !(ip_src = libnet_name2addr4(netcontext, ip_src_str, LIBNET_RESOLVE)))
+    {
+        fprintf(stderr,"Bad source IP address: %s\n", ip_src_str);
+        fprintf(stderr,"%s\n", libnet_geterror(netcontext));
+        exit(1);
+    }
+
+    if (ip_dst_test 
+            && !(ip_dst = libnet_name2addr4(netcontext, ip_dst_str, LIBNET_RESOLVE)))
+    {
+        fprintf(stderr,"Bad destination IP address: %s\n", ip_dst_str);
+        fprintf(stderr,"%s\n", libnet_geterror(netcontext));
+        exit(1);
+    }
+
+    if (igmp_group_test && !(igmp_group = libnet_name2addr4(netcontext, igmp_group_str, LIBNET_RESOLVE)))
+    {
+        fprintf(stderr,"Bad group IP address: %s\n", optarg);
+        fprintf(stderr,"%s\n", libnet_geterror(netcontext));
+        exit(1);
+    }
+
+    printf("    IP SRC IP  = %s\n", ip_src_str);
+    printf("    IP DEST IP = %s\n", ip_dst_str);
+    printf("    IGMP TYPE  = 0x%02x\n", igmp_type);
+    printf("    IGMP CODE  = 0x%02x\n", igmp_code);
+    printf("    IGMP GROUP = %s\n", igmp_group_str);
+    printf("    GROUP TEST = %d\n", igmp_group_test);
+
+    /*
+       int test = 1;
+       if ( *(char *) test == 1) {
+    // little endian
+    printf("little endian\n");
+    } else {
+    // big endian
+    printf("big endian\n");
+    }
+    */
+
+    ptag = libnet_build_igmp(
+            igmp_type,              // IGMP type 
+            igmp_code,              // IGMP code or TTL 
+            0,                      // checksum
+            htonl(igmp_group),                // ip addr 
+            NULL,                      // Ptr to packet data (or null) 
+            0,                      // Packet payload length 
+            netcontext,             // Ptr to libnet context
+            0);                     // Build a new packet header
+    if (ptag < 0)
+    { 
+        fprintf(stderr, "Error while building IGMP header data (err %d)\n", ptag);
+        fprintf(stderr,"%s\n", libnet_geterror(netcontext));
+        exit(1);
+    }
+
+
+    u_int8_t ipopt[2];
+    ipopt[0] = IPOPT_RA;
+    ipopt[1] = 4;
+    ptag = libnet_build_ipv4_options(
+            ipopt,       // options
+            2,           // options_s (length of option string)
+            netcontext,  // libnet context
+            0         // ptag
+            );                
+    if (ptag < 0)
+    { 
+        fprintf(stderr, "Error while building IPv4 options data (err %d)\n", ptag);
+    }
+
+    ptag = libnet_build_ipv4(LIBNET_IPV4_H + LIBNET_IGMP_H,  // pkg size + data
+            0,         // IP tos
+            getpid(),  // IP ID
+            IP_DF,         // frag flags and offset
+            1,         // TTL
+            IPPROTO_IGMP,           // transport protocol
+            0,                      // checksum
+            ip_src,                 // source IP
+            ip_dst,                 // destination IP
+            NULL,                   // payload (none)
+            0,                      // payload length
+            netcontext,             // libnet context
+            0                       // build a new header
+            );                
+    if (ptag < 0)
+    { 
+        fprintf(stderr, "Error while building IPv4 header data (err %d)\n", ptag);
+        fprintf(stderr,"%s\n", libnet_geterror(netcontext));
+        exit(1);
+    }
+
+    printf("  done\n"); //IGMP content
+
+    c = libnet_write(netcontext);
+    if (c < 0)
+    {
+        fprintf(stderr,"%s\n", libnet_geterror(netcontext));
+    }
+    else
+    {
+        printf("construction and injection completed, wrote all %d bytes\n", c);
+    } 
+
+    /*
+     *  Free packet memory.
+     */
+    libnet_diag_dump_pblock(netcontext);
     libnet_destroy(netcontext);
-    return 0;
+    exit(0);
+
+    return (c == -1 ? EXIT_FAILURE : EXIT_SUCCESS);
 }
+
+// vim: ts=4 sts=4 sw=4 et