long stream_pfring_open(struct stream** stptr, const struct ether_addr* addr, const char* iface, size_t buffer_size){ int ret = 0; assert(stptr); /* validate arguments */ if ( !(addr && iface) ){ return EINVAL; } /* get MTU for interface */ const int if_mtu = iface_mtu(iface); if ( if_mtu < 0 ){ return errno; } pfring_config(99); /* open pfring */ char* derp = strdup(iface); pfring* pd = pfring_open(derp, 1, 9000, 0); if ( !pd ){ return errno; } pfring_set_application_name(pd, "libcap_utils"); uint32_t version; pfring_version(pd, &version); fprintf(stderr, "Using PF_RING v.%d.%d.%d\n", (version & 0xFFFF0000) >> 16, (version & 0x0000FF00) >> 8, version & 0x000000FF); if((ret = pfring_set_direction(pd, rx_and_tx_direction)) != 0) fprintf(stderr, "pfring_set_direction returned %d (perhaps you use a direction other than rx only with DNA ?)\n", ret); if((ret = pfring_set_socket_mode(pd, recv_only_mode)) != 0) fprintf(stderr, "pfring_set_socket_mode returned [rc=%d]\n", ret); char bpfFilter[] = "ether proto 0x810"; ret = pfring_set_bpf_filter(pd, bpfFilter); if ( ret != 0 ) { fprintf(stderr, "pfring_set_bpf_filter(%s) returned %d\n", bpfFilter, ret); } else { fprintf(stderr, "Successfully set BPF filter '%s'\n", bpfFilter); } /* default buffer_size of 25*MTU */ if ( buffer_size == 0 ){ buffer_size = 250 * if_mtu; } /* ensure buffer is a multiple of MTU and can hold at least one frame */ if ( buffer_size < if_mtu ){ return ERROR_BUFFER_LENGTH; } else if ( buffer_size % if_mtu != 0 ){ return ERROR_BUFFER_MULTIPLE; } /* additional memory for the frame pointers */ size_t frames = buffer_size / if_mtu; size_t frame_offset = sizeof(char*) * frames; buffer_size += frame_offset; /* Initialize the structure */ if ( (ret = stream_alloc(stptr, PROTOCOL_ETHERNET_MULTICAST, sizeof(struct stream_pfring), buffer_size) != 0) ){ return ret; } struct stream_pfring* st = (struct stream_pfring*)*stptr; st->pd = pd; st->num_address = 0; st->if_mtu = if_mtu; memset(st->seqnum, 0, sizeof(long unsigned int) * MAX_ADDRESS); if (pfring_enable_ring(pd) != 0) { fprintf(stderr, "Unable to enable ring :-(\n"); pfring_close(pd); return(-1); } /* setup buffer pointers (see brief overview at struct declaration) */ st->num_frames = frames; st->num_packets = 0; st->read_ptr = NULL; st->base.readPos = 0; st->base.writePos = 0; for ( unsigned int i = 0; i < frames; i++ ){ st->frame[i] = st->base.buffer + frame_offset + i * if_mtu; } /* add membership to group */ if ( (ret=stream_pfring_add(&st->base, addr)) != 0 ){ return ret; } /* if ( (ret=stream_pfring_init(stptr, addr, iface, ETH_P_ALL, buffer_size)) != 0 ){ return ret; } */ st->base.type = PROTOCOL_ETHERNET_MULTICAST; st->base.FH.comment_size = 0; st->base.comment = NULL; /* callbacks */ st->base.fill_buffer = NULL; st->base.destroy = (destroy_callback)destroy; st->base.write = NULL; st->base.read = (read_callback)stream_pfring_read; return 0; }
int main(int argc, char* argv[]) { char c, *pcap_in = NULL, mac_address[6]; int promisc, i, verbose = 0, active_poll = 0, reforge_mac = 0; u_int mac_a, mac_b, mac_c, mac_d, mac_e, mac_f; char buffer[1500]; int send_len = 60; u_int32_t num = 1; int bind_core = -1; u_int16_t cpu_percentage = 0; double gbit_s = 0, td, pps; ticks tick_start = 0, tick_delta = 0; ticks hz = 0; struct packet *tosend; while((c = getopt(argc,argv,"hi:n:g:l:af:r:vm:" #if 0 "b:" #endif )) != -1) { switch(c) { case 'h': printHelp(); break; case 'i': in_dev = strdup(optarg); break; case 'f': pcap_in = strdup(optarg); break; case 'n': num = atoi(optarg); break; case 'g': bind_core = atoi(optarg); break; case 'l': send_len = atoi(optarg); break; case 'v': verbose = 1; break; case 'a': active_poll = 1; break; case 'r': sscanf(optarg, "%lf", &gbit_s); break; #if 0 case 'b': cpu_percentage = atoi(optarg); #endif break; case 'm': if(sscanf(optarg, "%02X:%02X:%02X:%02X:%02X:%02X", &mac_a, &mac_b, &mac_c, &mac_d, &mac_e, &mac_f) != 6) { printf("Invalid MAC address format (XX:XX:XX:XX:XX:XX)\n"); return(0); } else { reforge_mac = 1; mac_address[0] = mac_a, mac_address[1] = mac_b, mac_address[2] = mac_c; mac_address[3] = mac_d, mac_address[4] = mac_e, mac_address[5] = mac_f; } break; } } if(in_dev == NULL) printHelp(); printf("Sending packets on %s\n", in_dev); /* hardcode: promisc=1, to_ms=500 */ promisc = 1; pd = pfring_open(in_dev, promisc, 1500, 0); if(pd == NULL) { printf("pfring_open %s error\n", in_dev); return(-1); } else { u_int32_t version; pfring_set_application_name(pd, "pfdnasend"); pfring_version(pd, &version); printf("Using PF_RING v.%d.%d.%d\n", (version & 0xFFFF0000) >> 16, (version & 0x0000FF00) >> 8, version & 0x000000FF); } signal(SIGINT, sigproc); signal(SIGTERM, sigproc); signal(SIGINT, sigproc); if(send_len < 60) send_len = 60; if(gbit_s > 0) { /* cumputing usleep delay */ tick_start = getticks(); usleep(1); tick_delta = getticks() - tick_start; /* cumputing CPU freq */ tick_start = getticks(); usleep(1001); hz = (getticks() - tick_start - tick_delta) * 1000 /*kHz -> Hz*/; printf("Estimated CPU freq: %llu Hz\n", hz); /* computing max rate */ pps = ((gbit_s * 1000000000) / 8 /*byte*/) / (8 /*Preamble*/ + send_len + 4 /*CRC*/ + 12 /*IFG*/); td = (double)(hz / pps); tick_delta = (ticks)td; printf("Number of %d-byte Packet Per Second at %.2f Gbit/s: %.2f\n", (send_len + 4 /*CRC*/), gbit_s, pps); } if(pcap_in) { char ebuf[256]; u_char *pkt; struct pcap_pkthdr *h; pcap_t *pt = pcap_open_offline(pcap_in, ebuf); u_int num_pcap_pkts = 0; if(pt) { struct packet *last = NULL; while(1) { struct packet *p; int rc = pcap_next_ex(pt, &h, (const u_char**)&pkt); if(rc <= 0) break; p = (struct packet*)malloc(sizeof(struct packet)); if(p) { p->len = h->caplen; p->next = NULL; p->pkt = (char*)malloc(p->len); if(p->pkt == NULL) { printf("Not enough memory\n"); break; } else { memcpy(p->pkt, pkt, p->len); if(reforge_mac) memcpy(p->pkt, mac_address, 6); } if(last) { last->next = p; last = p; } else pkt_head = p, last = p; } else { printf("Not enough memory\n"); break; } if(verbose) printf("Read %d bytes packet from pcap file %s\n", p->len, pcap_in); num_pcap_pkts++; } /* while */ pcap_close(pt); printf("Read %d packets from pcap file %s\n", num_pcap_pkts, pcap_in); last->next = pkt_head; /* Loop */ num *= num_pcap_pkts; } else { printf("Unable to open file %s\n", pcap_in); pfring_close(pd); return(-1); } } else { struct packet *p; for(i=0; i<send_len; i++) buffer[i] = i; if(reforge_mac) memcpy(buffer, mac_address, 6); p = (struct packet*)malloc(sizeof(struct packet)); if(p) { p->len = send_len; p->next = p; /* Loop */ p->pkt = (char*)malloc(p->len); memcpy(p->pkt, buffer, send_len); pkt_head = p; } } if(bind_core >= 0) bind2core(bind_core); if(wait_for_packet && (cpu_percentage > 0)) { if(cpu_percentage > 99) cpu_percentage = 99; pfring_config(cpu_percentage); } if(!verbose) { signal(SIGALRM, my_sigalarm); alarm(1); } gettimeofday(&startTime, NULL); memcpy(&lastTime, &startTime, sizeof(startTime)); if(gbit_s > 0) tick_start = getticks(); tosend = pkt_head; i = 0; pfring_set_direction(pd, tx_only_direction); if(pfring_enable_ring(pd) != 0) { printf("Unable to enable ring :-(\n"); pfring_close(pd); return(-1); } while(!num || i < num) { int rc; redo: rc = pfring_send(pd, tosend->pkt, tosend->len, 0 /* Don't flush (it does PF_RING automatically) */); if(verbose) printf("[%d] pfring_send(%d) returned %d\n", i, tosend->len, rc); if(rc == -1) { /* Not enough space in buffer */ if(gbit_s == 0) { if(!active_poll) { if(bind_core >= 0) usleep(1); else pfring_poll(pd, 0); } } else { /* Just waste some time */ while((getticks() - tick_start) < (num_pkt_good_sent * tick_delta)) ; } goto redo; } else num_pkt_good_sent++, num_bytes_good_sent += tosend->len+24 /* 8 Preamble + 4 CRC + 12 IFG */, tosend = tosend->next; if(num > 0) i++; } /* for */ print_stats(0); pfring_close(pd); return(0); }
int main(int argc, char* argv[]) { char *device = NULL, c, *bind_mask = NULL; int snaplen = DEFAULT_SNAPLEN, rc, watermark = 0, rehash_rss = 0; packet_direction direction = rx_only_direction; long i; u_int16_t cpu_percentage = 0, poll_duration = 0; u_int32_t version; u_int32_t flags = 0; startTime.tv_sec = 0; thiszone = gmt2local(0); numCPU = sysconf( _SC_NPROCESSORS_ONLN ); memset(thread_core_affinity, -1, sizeof(thread_core_affinity)); while((c = getopt(argc,argv,"hi:l:mvae:w:b:rp:g:")) != -1) { switch(c) { case 'h': printHelp(); return(0); break; case 'a': wait_for_packet = 0; break; case 'e': switch(atoi(optarg)) { case rx_and_tx_direction: case rx_only_direction: case tx_only_direction: direction = atoi(optarg); break; } break; case 'l': snaplen = atoi(optarg); break; case 'i': device = strdup(optarg); break; case 'm': use_extended_pkt_header = 1; break; case 'v': verbose = 1; break; case 'w': watermark = atoi(optarg); break; case 'b': cpu_percentage = atoi(optarg); break; case 'r': rehash_rss = 1; break; case 'p': poll_duration = atoi(optarg); break; case 'g': bind_mask = strdup(optarg); break; } } if(verbose) watermark = 1; if(device == NULL) device = DEFAULT_DEVICE; printf("Capturing from %s\n", device); flags |= PF_RING_PROMISC; /* hardcode: promisc=1 */ #if 0 flags |= PF_RING_DNA_FIXED_RSS_Q_0; #else flags |= PF_RING_DNA_SYMMETRIC_RSS; /* Note that symmetric RSS is ignored by non-DNA drivers */ #endif if(use_extended_pkt_header) flags |= PF_RING_LONG_HEADER; num_channels = pfring_open_multichannel(device, snaplen, flags, ring); if(num_channels <= 0) { fprintf(stderr, "pfring_open_multichannel() returned %d [%s]\n", num_channels, strerror(errno)); return(-1); } if (num_channels > MAX_NUM_THREADS) { printf("WARNING: Too many channels (%d), using %d channels\n", num_channels, MAX_NUM_THREADS); num_channels = MAX_NUM_THREADS; } else if (num_channels > numCPU) { printf("WARNING: More channels (%d) than available cores (%d), using %d channels\n", num_channels, numCPU, numCPU); num_channels = numCPU; } else { printf("Found %d channels\n", num_channels); } if(bind_mask != NULL) { char *id = strtok(bind_mask, ":"); int idx = 0; while(id != NULL) { thread_core_affinity[idx++] = atoi(id) % numCPU; if(idx >= num_channels) break; id = strtok(NULL, ":"); } } pfring_version(ring[0], &version); printf("Using PF_RING v.%d.%d.%d\n", (version & 0xFFFF0000) >> 16, (version & 0x0000FF00) >> 8, version & 0x000000FF); for(i=0; i<num_channels; i++) { char buf[32]; snprintf(buf, sizeof(buf), "pfcount_multichannel-thread %ld", i); pfring_set_application_name(ring[i], buf); if((rc = pfring_set_direction(ring[i], direction)) != 0) fprintf(stderr, "pfring_set_direction returned %d [direction=%d] (you can't capture TX with DNA)\n", rc, direction); if((rc = pfring_set_socket_mode(ring[i], recv_only_mode)) != 0) fprintf(stderr, "pfring_set_socket_mode returned [rc=%d]\n", rc); if(watermark > 0) { if((rc = pfring_set_poll_watermark(ring[i], watermark)) != 0) fprintf(stderr, "pfring_set_poll_watermark returned [rc=%d][watermark=%d]\n", rc, watermark); } #if 0 setup_steering(ring[0], "192.168.30.207", -1); /* UTDF */ setup_steering(ring[0], "224.0.1.92", 1); setup_steering(ring[0], "224.0.1.94", 1); setup_steering(ring[0], "224.0.1.96", 1); /* BATS */ setup_steering(ring[0], "224.0.62.2", 2); /* default: should go to channel 0 */ #endif if(rehash_rss) pfring_enable_rss_rehash(ring[i]); if(poll_duration > 0) pfring_set_poll_duration(ring[i], poll_duration); pfring_enable_ring(ring[i]); pthread_create(&pd_thread[i], NULL, packet_consumer_thread, (void*)i); usleep(500); } if(cpu_percentage > 0) { if(cpu_percentage > 99) cpu_percentage = 99; pfring_config(cpu_percentage); } signal(SIGINT, sigproc); signal(SIGTERM, sigproc); signal(SIGINT, sigproc); if(!verbose) { signal(SIGALRM, my_sigalarm); alarm(ALARM_SLEEP); } for(i=0; i<num_channels; i++) { pthread_join(pd_thread[i], NULL); pfring_close(ring[i]); } return(0); }
int main(int argc, char* argv[]) { char c, *pcap_in = NULL; int i, verbose = 0, active_poll = 0, disable_zero_copy = 0; int use_zero_copy_tx = 0; u_int mac_a, mac_b, mac_c, mac_d, mac_e, mac_f; char buffer[9000]; u_int32_t num_to_send = 0; int bind_core = -1; u_int16_t cpu_percentage = 0; double gbit_s = 0, td, pps; ticks tick_start = 0, tick_delta = 0; ticks hz = 0; struct packet *tosend; u_int num_tx_slots = 0; int num_balanced_pkts = 1, watermark = 0; u_int num_pcap_pkts = 0; while((c = getopt(argc,argv,"b:hi:n:g:l:af:r:vm:w:zx:" #if 0 "b:" #endif )) != -1) { switch(c) { case 'b': num_balanced_pkts = atoi(optarg); break; case 'h': printHelp(); break; case 'i': in_dev = strdup(optarg); break; case 'f': pcap_in = strdup(optarg); break; case 'n': num_to_send = atoi(optarg); break; case 'g': bind_core = atoi(optarg); break; case 'l': send_len = atoi(optarg); break; case 'x': if_index = atoi(optarg); break; case 'v': verbose = 1; break; case 'a': active_poll = 1; break; case 'r': sscanf(optarg, "%lf", &gbit_s); break; #if 0 case 'b': cpu_percentage = atoi(optarg); #endif break; case 'm': if(sscanf(optarg, "%02X:%02X:%02X:%02X:%02X:%02X", &mac_a, &mac_b, &mac_c, &mac_d, &mac_e, &mac_f) != 6) { printf("Invalid MAC address format (XX:XX:XX:XX:XX:XX)\n"); return(0); } else { reforge_mac = 1; mac_address[0] = mac_a, mac_address[1] = mac_b, mac_address[2] = mac_c; mac_address[3] = mac_d, mac_address[4] = mac_e, mac_address[5] = mac_f; } break; case 'w': watermark = atoi(optarg); if(watermark < 1) watermark = 1; break; case 'z': disable_zero_copy = 1; break; } } if((in_dev == NULL) || (num_balanced_pkts < 1)) printHelp(); printf("Sending packets on %s\n", in_dev); pd = pfring_open(in_dev, 1500, 0 /* PF_RING_PROMISC */); if(pd == NULL) { printf("pfring_open %s error [%s]\n", in_dev, strerror(errno)); return(-1); } else { u_int32_t version; pfring_set_application_name(pd, "pfdnasend"); pfring_version(pd, &version); printf("Using PF_RING v.%d.%d.%d\n", (version & 0xFFFF0000) >> 16, (version & 0x0000FF00) >> 8, version & 0x000000FF); } if (!pd->send && pd->send_ifindex && if_index == -1) { printf("Please use -x <if index>\n"); return -1; } if(watermark > 0) { int rc; if((rc = pfring_set_tx_watermark(pd, watermark)) < 0) printf("pfring_set_tx_watermark() failed [rc=%d]\n", rc); } signal(SIGINT, sigproc); signal(SIGTERM, sigproc); signal(SIGINT, sigproc); if(send_len < 60) send_len = 60; if(gbit_s != 0) { /* cumputing usleep delay */ tick_start = getticks(); usleep(1); tick_delta = getticks() - tick_start; /* cumputing CPU freq */ tick_start = getticks(); usleep(1001); hz = (getticks() - tick_start - tick_delta) * 1000 /*kHz -> Hz*/; printf("Estimated CPU freq: %lu Hz\n", (long unsigned int)hz); } if(pcap_in) { char ebuf[256]; u_char *pkt; struct pcap_pkthdr *h; pcap_t *pt = pcap_open_offline(pcap_in, ebuf); struct timeval beginning = { 0, 0 }; int avg_send_len = 0; if(pt) { struct packet *last = NULL; while(1) { struct packet *p; int rc = pcap_next_ex(pt, &h, (const u_char**)&pkt); if(rc <= 0) break; if (num_pcap_pkts == 0) { beginning.tv_sec = h->ts.tv_sec; beginning.tv_usec = h->ts.tv_usec; } p = (struct packet*)malloc(sizeof(struct packet)); if(p) { p->len = h->caplen; p->ticks_from_beginning = (((h->ts.tv_sec - beginning.tv_sec) * 1000000) + (h->ts.tv_usec - beginning.tv_usec)) * hz / 1000000; p->next = NULL; p->pkt = (char*)malloc(p->len); if(p->pkt == NULL) { printf("Not enough memory\n"); break; } else { memcpy(p->pkt, pkt, p->len); if(reforge_mac) memcpy(p->pkt, mac_address, 6); } if(last) { last->next = p; last = p; } else pkt_head = p, last = p; } else { printf("Not enough memory\n"); break; } if(verbose) printf("Read %d bytes packet from pcap file %s [%lu.%lu Secs = %lu ticks@%luhz from beginning]\n", p->len, pcap_in, h->ts.tv_sec - beginning.tv_sec, h->ts.tv_usec - beginning.tv_usec, (long unsigned int)p->ticks_from_beginning, (long unsigned int)hz); avg_send_len += p->len; num_pcap_pkts++; } /* while */ avg_send_len /= num_pcap_pkts; pcap_close(pt); printf("Read %d packets from pcap file %s\n", num_pcap_pkts, pcap_in); last->next = pkt_head; /* Loop */ send_len = avg_send_len; } else { printf("Unable to open file %s\n", pcap_in); pfring_close(pd); return(-1); } } else { struct packet *p = NULL, *last = NULL; for (i = 0; i < num_balanced_pkts; i++) { forge_udp_packet(buffer, i); p = (struct packet *) malloc(sizeof(struct packet)); if(p) { if (i == 0) pkt_head = p; p->len = send_len; p->ticks_from_beginning = 0; p->next = pkt_head; p->pkt = (char*)malloc(p->len); if (p->pkt == NULL) { printf("Not enough memory\n"); break; } memcpy(p->pkt, buffer, send_len); if (last != NULL) last->next = p; last = p; } } } if(gbit_s > 0) { /* computing max rate */ pps = ((gbit_s * 1000000000) / 8 /*byte*/) / (8 /*Preamble*/ + send_len + 4 /*CRC*/ + 12 /*IFG*/); td = (double)(hz / pps); tick_delta = (ticks)td; printf("Number of %d-byte Packet Per Second at %.2f Gbit/s: %.2f\n", (send_len + 4 /*CRC*/), gbit_s, pps); } if(bind_core >= 0) bind2core(bind_core); if(wait_for_packet && (cpu_percentage > 0)) { if(cpu_percentage > 99) cpu_percentage = 99; pfring_config(cpu_percentage); } if(!verbose) { signal(SIGALRM, my_sigalarm); alarm(1); } gettimeofday(&startTime, NULL); memcpy(&lastTime, &startTime, sizeof(startTime)); pfring_set_socket_mode(pd, send_only_mode); if(pfring_enable_ring(pd) != 0) { printf("Unable to enable ring :-(\n"); pfring_close(pd); return(-1); } use_zero_copy_tx = 0; if((!disable_zero_copy) && (pd->dna_get_num_tx_slots != NULL) && (pd->dna_get_next_free_tx_slot != NULL) && (pd->dna_copy_tx_packet_into_slot != NULL)) { tosend = pkt_head; num_tx_slots = pd->dna_get_num_tx_slots(pd); if(num_tx_slots > 0 && (((num_to_send > 0) && (num_to_send <= num_tx_slots)) || ( pcap_in && (num_pcap_pkts <= num_tx_slots) && (num_tx_slots % num_pcap_pkts == 0)) || (!pcap_in && (num_balanced_pkts <= num_tx_slots) && (num_tx_slots % num_balanced_pkts == 0)))) { int ret; u_int first_free_slot = pd->dna_get_next_free_tx_slot(pd); for(i=0; i<num_tx_slots; i++) { ret = pfring_copy_tx_packet_into_slot(pd, (first_free_slot+i)%num_tx_slots, tosend->pkt, tosend->len); if(ret < 0) break; tosend = tosend->next; } use_zero_copy_tx = 1; printf("Using zero-copy TX\n"); } else { printf("NOT using zero-copy: TX ring size (%u) is not a multiple of the number of unique packets to send (%u)\n", num_tx_slots, pcap_in ? num_pcap_pkts : num_balanced_pkts); } } else { if (!disable_zero_copy) printf("NOT using zero-copy: not supported by the driver\n"); } tosend = pkt_head; i = 0; if(gbit_s != 0) tick_start = getticks(); while((num_to_send == 0) || (i < num_to_send)) { int rc; redo: if (if_index != -1) rc = pfring_send_ifindex(pd, tosend->pkt, tosend->len, gbit_s < 0 ? 1 : 0 /* Don't flush (it does PF_RING automatically) */, if_index); else if(use_zero_copy_tx) /* We pre-filled the TX slots */ rc = pfring_send(pd, NULL, tosend->len, gbit_s < 0 ? 1 : 0 /* Don't flush (it does PF_RING automatically) */); else rc = pfring_send(pd, tosend->pkt, tosend->len, gbit_s < 0 ? 1 : 0 /* Don't flush (it does PF_RING automatically) */); if(verbose) printf("[%d] pfring_send(%d) returned %d\n", i, tosend->len, rc); if(rc == PF_RING_ERROR_INVALID_ARGUMENT) { printf("Attempting to send invalid packet [len: %u][MTU: %u]%s\n", tosend->len, pd->mtu_len, if_index != -1 ? " or using a wrong interface id" : ""); } else if(rc < 0) { /* Not enough space in buffer */ if(!active_poll) { #if 1 usleep(1); #else if(bind_core >= 0) usleep(1); else pfring_poll(pd, 0); //sched_yield(); #endif } goto redo; } num_pkt_good_sent++; num_bytes_good_sent += tosend->len + 24 /* 8 Preamble + 4 CRC + 12 IFG */; tosend = tosend->next; if (use_zero_copy_tx && (num_pkt_good_sent == num_tx_slots)) tosend = pkt_head; if(gbit_s > 0) { /* rate set */ while((getticks() - tick_start) < (num_pkt_good_sent * tick_delta)) ; } else if (gbit_s < 0) { /* real pcap rate */ if (tosend->ticks_from_beginning == 0) tick_start = getticks(); /* first packet, resetting time */ while((getticks() - tick_start) < tosend->ticks_from_beginning) ; } if(num_to_send > 0) i++; } /* for */ print_stats(0); pfring_close(pd); return(0); }