Esempio n. 1
0
static void enter_mode_rx_only_or_dump(struct mode *mode)
{
	int sock, irq, ifindex, fd = 0, ret;
	unsigned int size, it = 0;
	unsigned long fcnt = 0;
	short ifflags = 0;
	uint8_t *packet;
	struct ring rx_ring;
	struct pollfd rx_poll;
	struct frame_map *hdr;
	struct sock_fprog bpf_ops;

	if (!device_up_and_running(mode->device_in))
		panic("Device not up and running!\n");

	set_memcpy();
	sock = pf_socket();

	if (mode->dump) {
		struct stat tmp;
		memset(&tmp, 0, sizeof(tmp));
		ret = stat(mode->device_out, &tmp);
		if (ret < 0) {
			mode->dump_dir = 0;
			goto try_file;
		}
		mode->dump_dir = !!S_ISDIR(tmp.st_mode);
		if (mode->dump_dir) {
			fd = begin_multi_pcap_file(mode);
		} else {
try_file:
			fd = begin_single_pcap_file(mode);
		}
	}

	memset(&rx_ring, 0, sizeof(rx_ring));
	memset(&rx_poll, 0, sizeof(rx_poll));
	memset(&bpf_ops, 0, sizeof(bpf_ops));

	ifindex = device_ifindex(mode->device_in);
	size = ring_size(mode->device_in, mode->reserve_size);

	enable_kernel_bpf_jit_compiler();
	bpf_parse_rules(mode->filter, &bpf_ops);
	bpf_attach_to_sock(sock, &bpf_ops);

	setup_rx_ring_layout(sock, &rx_ring, size, mode->jumbo_support);
	create_rx_ring(sock, &rx_ring);
	mmap_rx_ring(sock, &rx_ring);
	alloc_rx_ring_frames(&rx_ring);
	bind_rx_ring(sock, &rx_ring, ifindex);

	prepare_polling(sock, &rx_poll);
	dissector_init_all(mode->print_mode);

	if (mode->cpu >= 0 && ifindex > 0) {
		irq = device_irq_number(mode->device_in);
		device_bind_irq_to_cpu(mode->cpu, irq);
		printf("IRQ: %s:%d > CPU%d\n", mode->device_in, irq, 
		       mode->cpu);
	}

	if (mode->promiscuous == true) {
		ifflags = enter_promiscuous_mode(mode->device_in);
		printf("PROMISC\n");
	}

	printf("BPF:\n");
	bpf_dump_all(&bpf_ops);
	printf("MD: RX %s\n\n", mode->dump ? pcap_ops[mode->pcap]->name : "");

	while (likely(sigint == 0)) {
		while (user_may_pull_from_rx(rx_ring.frames[it].iov_base)) {
			hdr = rx_ring.frames[it].iov_base;
			packet = ((uint8_t *) hdr) + hdr->tp_h.tp_mac;
			fcnt++;

			if (mode->packet_type != PACKET_ALL)
				if (mode->packet_type != hdr->s_ll.sll_pkttype)
					goto next;
			if (unlikely(rx_ring.layout.tp_frame_size <
				     hdr->tp_h.tp_snaplen)) {
				fprintf(stderr, "Skipping too large packet! "
					"No jumbo support selected?\n");
				fflush(stderr);
				goto next;
			}
			if (mode->dump) {
				struct pcap_pkthdr phdr;
				tpacket_hdr_to_pcap_pkthdr(&hdr->tp_h, &phdr);
				ret = pcap_ops[mode->pcap]->write_pcap_pkt(fd, &phdr,
									   packet, phdr.len);
				if (unlikely(ret != sizeof(phdr) + phdr.len))
					panic("Write error to pcap!\n");
			}

			show_frame_hdr(hdr, mode->print_mode, RING_MODE_INGRESS);
			dissector_entry_point(packet, hdr->tp_h.tp_snaplen,
					      mode->link_type);

			if (frame_cnt_max != 0 && fcnt >= frame_cnt_max) {
				sigint = 1;
				break;
			}
next:
			kernel_may_pull_from_rx(&hdr->tp_h);
			next_slot(&it, &rx_ring);

			if (unlikely(sigint == 1))
				break;
			if (mode->dump && next_dump) {
				struct tpacket_stats kstats;
				socklen_t slen = sizeof(kstats);
				memset(&kstats, 0, sizeof(kstats));
				getsockopt(sock, SOL_PACKET, PACKET_STATISTICS,
					   &kstats, &slen);
				fd = next_multi_pcap_file(mode, fd);
				next_dump = false;
				if (mode->print_mode == FNTTYPE_PRINT_NONE) {
					printf(".(+%u/-%u)", kstats.tp_packets - kstats.tp_drops,
					       kstats.tp_drops);
					fflush(stdout);
				}
			}
		}

		poll(&rx_poll, 1, -1);
		poll_error_maybe_die(sock, &rx_poll);
	}

	if (!(mode->dump_dir && mode->print_mode == FNTTYPE_PRINT_NONE))
		sock_print_net_stats(sock);
	else {
		printf("\n\n");
		fflush(stdout);
	}
	dissector_cleanup_all();
	destroy_rx_ring(sock, &rx_ring);
	if (mode->promiscuous == true)
		leave_promiscuous_mode(mode->device_in, ifflags);
	close(sock);
	if (mode->dump) {
		if (mode->dump_dir)
			finish_multi_pcap_file(mode, fd);
		else
			finish_single_pcap_file(mode, fd);
	}
}
Esempio n. 2
0
/* If netsniff-ngs in device is on a tap, it can efficiently filter out 
 * some interesting packets and give them to the out device for testing
 * or debugging for instance. */
static void enter_mode_rx_to_tx(struct mode *mode)
{
	int rx_sock, ifindex_in, ifindex_out;
	unsigned int size_in, size_out, it_in = 0, it_out = 0;
	unsigned long fcnt = 0;
	uint8_t *in, *out;
	short ifflags = 0;
	struct frame_map *hdr_in, *hdr_out;
	struct ring tx_ring;
	struct ring rx_ring;
	struct pollfd rx_poll;
	struct sock_fprog bpf_ops;

	if (!strncmp(mode->device_in, mode->device_out,
		     strlen(mode->device_in)))
		panic("Ingress/egress devices must be different!\n");
	if (!device_up_and_running(mode->device_out))
		panic("Egress device not up and running!\n");
	if (!device_up_and_running(mode->device_in))
		panic("Ingress device not up and running!\n");

	set_memcpy();
	rx_sock = pf_socket();
	tx_sock = pf_socket();

	memset(&tx_ring, 0, sizeof(tx_ring));
	memset(&rx_ring, 0, sizeof(rx_ring));
	memset(&rx_poll, 0, sizeof(rx_poll));
	memset(&bpf_ops, 0, sizeof(bpf_ops));

	ifindex_in = device_ifindex(mode->device_in);
	size_in = ring_size(mode->device_in, mode->reserve_size);

	ifindex_out = device_ifindex(mode->device_out);
	size_out = ring_size(mode->device_out, mode->reserve_size);

	enable_kernel_bpf_jit_compiler();
	bpf_parse_rules(mode->filter, &bpf_ops);
	bpf_attach_to_sock(rx_sock, &bpf_ops);

	setup_rx_ring_layout(rx_sock, &rx_ring, size_in, mode->jumbo_support);
	create_rx_ring(rx_sock, &rx_ring);
	mmap_rx_ring(rx_sock, &rx_ring);
	alloc_rx_ring_frames(&rx_ring);
	bind_rx_ring(rx_sock, &rx_ring, ifindex_in);
	prepare_polling(rx_sock, &rx_poll);

	set_packet_loss_discard(tx_sock);
	setup_tx_ring_layout(tx_sock, &tx_ring, size_out, mode->jumbo_support);
	create_tx_ring(tx_sock, &tx_ring);
	mmap_tx_ring(tx_sock, &tx_ring);
	alloc_tx_ring_frames(&tx_ring);
	bind_tx_ring(tx_sock, &tx_ring, ifindex_out);

	mt_init_by_seed_time();
	dissector_init_all(mode->print_mode);

	 if (mode->promiscuous == true) {
		ifflags = enter_promiscuous_mode(mode->device_in);
		printf("PROMISC\n");
	}

	if (mode->kpull)
		interval = mode->kpull;

	itimer.it_interval.tv_sec = 0;
	itimer.it_interval.tv_usec = interval;
	itimer.it_value.tv_sec = 0;
	itimer.it_value.tv_usec = interval;
	setitimer(ITIMER_REAL, &itimer, NULL);

	printf("BPF:\n");
	bpf_dump_all(&bpf_ops);
	printf("MD: RXTX %luus\n\n", interval);
	printf("Running! Hang up with ^C!\n\n");

	while (likely(sigint == 0)) {
		while (user_may_pull_from_rx(rx_ring.frames[it_in].iov_base)) {
			hdr_in = rx_ring.frames[it_in].iov_base;
			in = ((uint8_t *) hdr_in) + hdr_in->tp_h.tp_mac;
			fcnt++;
			if (mode->packet_type != PACKET_ALL)
				if (mode->packet_type != hdr_in->s_ll.sll_pkttype)
					goto next;

			hdr_out = tx_ring.frames[it_out].iov_base;
			out = ((uint8_t *) hdr_out) + TPACKET_HDRLEN -
			      sizeof(struct sockaddr_ll);

			/* If we cannot pull, look for a different slot. */
			for (; !user_may_pull_from_tx(tx_ring.frames[it_out].iov_base) &&
			       likely(!sigint);) {
				if (mode->randomize)
					next_rnd_slot(&it_out, &tx_ring);
				else
					next_slot(&it_out, &tx_ring);
				hdr_out = tx_ring.frames[it_out].iov_base;
				out = ((uint8_t *) hdr_out) + TPACKET_HDRLEN -
				      sizeof(struct sockaddr_ll);
			}

			tpacket_hdr_clone(&hdr_out->tp_h, &hdr_in->tp_h);
			__memcpy(out, in, hdr_in->tp_h.tp_len);

			kernel_may_pull_from_tx(&hdr_out->tp_h);
			if (mode->randomize)
				next_rnd_slot(&it_out, &tx_ring);
			else
				next_slot(&it_out, &tx_ring);

			/* Should actually be avoided ... */
			show_frame_hdr(hdr_in, mode->print_mode, RING_MODE_INGRESS);
			dissector_entry_point(in, hdr_in->tp_h.tp_snaplen,
					      mode->link_type);

			if (frame_cnt_max != 0 && fcnt >= frame_cnt_max) {
				sigint = 1;
				break;
			}
next:
			kernel_may_pull_from_rx(&hdr_in->tp_h);
			next_slot(&it_in, &rx_ring);

			if (unlikely(sigint == 1))
				goto out;
		}

		poll(&rx_poll, 1, -1);
		poll_error_maybe_die(rx_sock, &rx_poll);
	}
out:
	sock_print_net_stats(rx_sock);

	dissector_cleanup_all();
	destroy_tx_ring(tx_sock, &tx_ring);
	destroy_rx_ring(rx_sock, &rx_ring);

	if (mode->promiscuous == true)
		leave_promiscuous_mode(mode->device_in, ifflags);

	close(tx_sock);
	close(rx_sock);
}
Esempio n. 3
0
static void recv_only_or_dump(struct ctx *ctx)
{
	uint8_t *packet;
	short ifflags = 0;
	int sock, irq, ifindex, fd = 0, ret;
	unsigned int size, it = 0;
	unsigned long frame_count = 0, skipped = 0;
	struct ring rx_ring;
	struct pollfd rx_poll;
	struct frame_map *hdr;
	struct sock_fprog bpf_ops;
	struct timeval start, end, diff;
	pcap_pkthdr_t phdr;

	if (!device_up_and_running(ctx->device_in) && !ctx->rfraw)
		panic("Device not up and running!\n");

	sock = pf_socket();

	if (ctx->rfraw) {
		ctx->device_trans = xstrdup(ctx->device_in);
		xfree(ctx->device_in);

		enter_rfmon_mac80211(ctx->device_trans, &ctx->device_in);
		ctx->link_type = LINKTYPE_IEEE802_11;
	}

	fmemset(&rx_ring, 0, sizeof(rx_ring));
	fmemset(&rx_poll, 0, sizeof(rx_poll));
	fmemset(&bpf_ops, 0, sizeof(bpf_ops));

	ifindex = device_ifindex(ctx->device_in);

	size = ring_size(ctx->device_in, ctx->reserve_size);

	enable_kernel_bpf_jit_compiler();

	bpf_parse_rules(ctx->filter, &bpf_ops, ctx->link_type);
	if (ctx->dump_bpf)
		bpf_dump_all(&bpf_ops);
	bpf_attach_to_sock(sock, &bpf_ops);

	set_sockopt_hwtimestamp(sock, ctx->device_in);

	setup_rx_ring_layout(sock, &rx_ring, size, ctx->jumbo);
	create_rx_ring(sock, &rx_ring, ctx->verbose);
	mmap_rx_ring(sock, &rx_ring);
	alloc_rx_ring_frames(&rx_ring);
	bind_rx_ring(sock, &rx_ring, ifindex);

	prepare_polling(sock, &rx_poll);
	dissector_init_all(ctx->print_mode);

	if (ctx->cpu >= 0 && ifindex > 0) {
		irq = device_irq_number(ctx->device_in);
		device_bind_irq_to_cpu(irq, ctx->cpu);

		if (ctx->verbose)
			printf("IRQ: %s:%d > CPU%d\n",
			       ctx->device_in, irq, ctx->cpu);
	}

	if (ctx->promiscuous)
		ifflags = enter_promiscuous_mode(ctx->device_in);

	drop_privileges(ctx->enforce, ctx->uid, ctx->gid);

	if (dump_to_pcap(ctx)) {
		__label__ try_file;
		struct stat stats;

		fmemset(&stats, 0, sizeof(stats));
		ret = stat(ctx->device_out, &stats);
		if (ret < 0) {
			ctx->dump_dir = 0;
			goto try_file;
		}

		ctx->dump_dir = S_ISDIR(stats.st_mode);
		if (ctx->dump_dir) {
			fd = begin_multi_pcap_file(ctx);
		} else {
		try_file:
			fd = begin_single_pcap_file(ctx);
		}
	}

	printf("Running! Hang up with ^C!\n\n");
	fflush(stdout);

	bug_on(gettimeofday(&start, NULL));

	while (likely(sigint == 0)) {
		while (user_may_pull_from_rx(rx_ring.frames[it].iov_base)) {
			__label__ next;

			hdr = rx_ring.frames[it].iov_base;
			packet = ((uint8_t *) hdr) + hdr->tp_h.tp_mac;
			frame_count++;

			if (ctx->packet_type != -1)
				if (ctx->packet_type != hdr->s_ll.sll_pkttype)
					goto next;

			if (unlikely(ring_frame_size(&rx_ring) < hdr->tp_h.tp_snaplen)) {
				skipped++;
				goto next;
			}

			if (dump_to_pcap(ctx)) {
				tpacket_hdr_to_pcap_pkthdr(&hdr->tp_h, &hdr->s_ll, &phdr, ctx->magic);

				ret = __pcap_io->write_pcap(fd, &phdr, ctx->magic, packet,
							    pcap_get_length(&phdr, ctx->magic));
				if (unlikely(ret != pcap_get_total_length(&phdr, ctx->magic)))
					panic("Write error to pcap!\n");
			}

			show_frame_hdr(hdr, ctx->print_mode);

			dissector_entry_point(packet, hdr->tp_h.tp_snaplen,
					      ctx->link_type, ctx->print_mode);

			if (frame_count_max != 0) {
				if (frame_count >= frame_count_max) {
					sigint = 1;
					break;
				}
			}

			next:

			kernel_may_pull_from_rx(&hdr->tp_h);

			it++;
			if (it >= rx_ring.layout.tp_frame_nr)
				it = 0;

			if (unlikely(sigint == 1))
				break;

			if (dump_to_pcap(ctx)) {
				if (ctx->dump_mode == DUMP_INTERVAL_SIZE) {
					interval += hdr->tp_h.tp_snaplen;

					if (interval > ctx->dump_interval) {
						next_dump = true;
						interval = 0;
					}
				}

				if (next_dump) {
					fd = next_multi_pcap_file(ctx, fd);
					next_dump = false;

					if (ctx->verbose)
						print_pcap_file_stats(sock, ctx, skipped);
				}
			}
		}

		poll(&rx_poll, 1, -1);
	}

	bug_on(gettimeofday(&end, NULL));
	timersub(&end, &start, &diff);

	if (!(ctx->dump_dir && ctx->print_mode == PRINT_NONE)) {
		sock_print_net_stats(sock, skipped);

		printf("\r%12lu  sec, %lu usec in total\n",
		       diff.tv_sec, diff.tv_usec);
	} else {
		printf("\n\n");
		fflush(stdout);
	}

	bpf_release(&bpf_ops);
	dissector_cleanup_all();
	destroy_rx_ring(sock, &rx_ring);

	if (ctx->promiscuous)
		leave_promiscuous_mode(ctx->device_in, ifflags);

	if (ctx->rfraw)
		leave_rfmon_mac80211(ctx->device_trans, ctx->device_in);

	if (dump_to_pcap(ctx)) {
		if (ctx->dump_dir)
			finish_multi_pcap_file(ctx, fd);
		else
			finish_single_pcap_file(ctx, fd);
	}

	close(sock);
}
Esempio n. 4
0
static void enter_mode_rx_only_or_dump(struct mode *mode)
{
	int sock, irq, ifindex, fd = 0, ret;
	unsigned int size, it = 0;
	unsigned long fcnt = 0, skipped = 0;
	short ifflags = 0;
	uint8_t *packet;
	struct ring rx_ring;
	struct pollfd rx_poll;
	struct frame_map *hdr;
	struct sock_fprog bpf_ops;
	struct timeval start, end, diff;

	if (!device_up_and_running(mode->device_in))
		panic("Device not up and running!\n");

	sock = pf_socket();

	if (mode->rfraw) {
		mode->device_trans = xstrdup(mode->device_in);
		xfree(mode->device_in);

		enter_rfmon_mac80211(mode->device_trans, &mode->device_in);
		mode->link_type = LINKTYPE_IEEE802_11;
	}

	if (mode->dump) {
		struct stat tmp;
		fmemset(&tmp, 0, sizeof(tmp));
		ret = stat(mode->device_out, &tmp);
		if (ret < 0) {
			mode->dump_dir = 0;
			goto try_file;
		}
		mode->dump_dir = !!S_ISDIR(tmp.st_mode);
		if (mode->dump_dir) {
			fd = begin_multi_pcap_file(mode);
		} else {
try_file:
			fd = begin_single_pcap_file(mode);
		}
	}

	fmemset(&rx_ring, 0, sizeof(rx_ring));
	fmemset(&rx_poll, 0, sizeof(rx_poll));
	fmemset(&bpf_ops, 0, sizeof(bpf_ops));

	ifindex = device_ifindex(mode->device_in);
	size = ring_size(mode->device_in, mode->reserve_size);

	enable_kernel_bpf_jit_compiler();
	bpf_parse_rules(mode->filter, &bpf_ops);
	bpf_attach_to_sock(sock, &bpf_ops);

	set_sockopt_hwtimestamp(sock, mode->device_in);
	setup_rx_ring_layout(sock, &rx_ring, size, mode->jumbo_support);
	create_rx_ring(sock, &rx_ring);
	mmap_rx_ring(sock, &rx_ring);
	alloc_rx_ring_frames(&rx_ring);
	bind_rx_ring(sock, &rx_ring, ifindex);

	prepare_polling(sock, &rx_poll);
	dissector_init_all(mode->print_mode);

	if (mode->cpu >= 0 && ifindex > 0) {
		irq = device_irq_number(mode->device_in);
		device_bind_irq_to_cpu(mode->cpu, irq);
		printf("IRQ: %s:%d > CPU%d\n", mode->device_in, irq, 
		       mode->cpu);
	}

	if (mode->promiscuous == true) {
		ifflags = enter_promiscuous_mode(mode->device_in);
		printf("PROMISC\n");
	}

	printf("BPF:\n");
	bpf_dump_all(&bpf_ops);
	printf("MD: RX %s ", mode->dump ? pcap_ops[mode->pcap]->name : "");
	if (mode->rfraw)
		printf("802.11 raw via %s ", mode->device_in);
#ifdef _LARGEFILE64_SOURCE
	printf("lf64 ");
#endif 
	ioprio_print();
	printf("\n");

	gettimeofday(&start, NULL);

	while (likely(sigint == 0)) {
		while (user_may_pull_from_rx(rx_ring.frames[it].iov_base)) {
			hdr = rx_ring.frames[it].iov_base;
			packet = ((uint8_t *) hdr) + hdr->tp_h.tp_mac;
			fcnt++;

			if (mode->packet_type != PACKET_ALL)
				if (mode->packet_type != hdr->s_ll.sll_pkttype)
					goto next;
			if (unlikely(ring_frame_size(&rx_ring) <
				     hdr->tp_h.tp_snaplen)) {
				skipped++;
				goto next;
			}
			if (mode->dump) {
				struct pcap_pkthdr phdr;
				tpacket_hdr_to_pcap_pkthdr(&hdr->tp_h, &phdr);
				ret = pcap_ops[mode->pcap]->write_pcap_pkt(fd, &phdr,
									   packet, phdr.len);
				if (unlikely(ret != sizeof(phdr) + phdr.len))
					panic("Write error to pcap!\n");
			}

			show_frame_hdr(hdr, mode->print_mode, RING_MODE_INGRESS);
			dissector_entry_point(packet, hdr->tp_h.tp_snaplen,
					      mode->link_type, mode->print_mode);

			if (frame_cnt_max != 0 && fcnt >= frame_cnt_max) {
				sigint = 1;
				break;
			}
next:
			kernel_may_pull_from_rx(&hdr->tp_h);
			next_slot_prerd(&it, &rx_ring);

			if (unlikely(sigint == 1))
				break;
			if (mode->dump && next_dump) {
				struct tpacket_stats kstats;
				socklen_t slen = sizeof(kstats);
				fmemset(&kstats, 0, sizeof(kstats));
				getsockopt(sock, SOL_PACKET, PACKET_STATISTICS,
					   &kstats, &slen);
				fd = next_multi_pcap_file(mode, fd);
				next_dump = false;
				if (mode->print_mode == FNTTYPE_PRINT_NONE) {
					printf(".(+%lu/-%lu)",
					       1UL * kstats.tp_packets -
					       kstats.tp_drops -
					       skipped, 1UL * kstats.tp_drops +
					       skipped);
					fflush(stdout);
				}
			}
		}

		poll(&rx_poll, 1, -1);
		poll_error_maybe_die(sock, &rx_poll);
	}

	gettimeofday(&end, NULL);
	diff = tv_subtract(end, start);

	if (!(mode->dump_dir && mode->print_mode == FNTTYPE_PRINT_NONE)) {
		sock_print_net_stats(sock, skipped);
		printf("\r%12lu  sec, %lu usec in total\n", diff.tv_sec,
		       diff.tv_usec);
	} else {
		printf("\n\n");
		fflush(stdout);
	}

	bpf_release(&bpf_ops);
	dissector_cleanup_all();
	destroy_rx_ring(sock, &rx_ring);

	if (mode->promiscuous == true)
		leave_promiscuous_mode(mode->device_in, ifflags);

	if (mode->rfraw)
		leave_rfmon_mac80211(mode->device_trans, mode->device_in);

	close(sock);

	if (mode->dump) {
		if (mode->dump_dir)
			finish_multi_pcap_file(mode, fd);
		else
			finish_single_pcap_file(mode, fd);
	}
}
Esempio n. 5
0
static void receive_to_xmit(struct ctx *ctx)
{
	short ifflags = 0;
	uint8_t *in, *out;
	int rx_sock, ifindex_in, ifindex_out;
	unsigned int size_in, size_out, it_in = 0, it_out = 0;
	unsigned long frame_count = 0;
	struct frame_map *hdr_in, *hdr_out;
	struct ring tx_ring, rx_ring;
	struct pollfd rx_poll;
	struct sock_fprog bpf_ops;

	if (!strncmp(ctx->device_in, ctx->device_out, IFNAMSIZ))
		panic("Ingress/egress devices must be different!\n");
	if (!device_up_and_running(ctx->device_out))
		panic("Egress device not up and running!\n");
	if (!device_up_and_running(ctx->device_in))
		panic("Ingress device not up and running!\n");

	rx_sock = pf_socket();
	tx_sock = pf_socket();

	fmemset(&tx_ring, 0, sizeof(tx_ring));
	fmemset(&rx_ring, 0, sizeof(rx_ring));
	fmemset(&rx_poll, 0, sizeof(rx_poll));
	fmemset(&bpf_ops, 0, sizeof(bpf_ops));

	ifindex_in = device_ifindex(ctx->device_in);
	ifindex_out = device_ifindex(ctx->device_out);

	size_in = ring_size(ctx->device_in, ctx->reserve_size);
	size_out = ring_size(ctx->device_out, ctx->reserve_size);

	enable_kernel_bpf_jit_compiler();

	bpf_parse_rules(ctx->filter, &bpf_ops, ctx->link_type);
	if (ctx->dump_bpf)
		bpf_dump_all(&bpf_ops);
	bpf_attach_to_sock(rx_sock, &bpf_ops);

	setup_rx_ring_layout(rx_sock, &rx_ring, size_in, ctx->jumbo);
	create_rx_ring(rx_sock, &rx_ring, ctx->verbose);
	mmap_rx_ring(rx_sock, &rx_ring);
	alloc_rx_ring_frames(&rx_ring);
	bind_rx_ring(rx_sock, &rx_ring, ifindex_in);
	prepare_polling(rx_sock, &rx_poll);

	set_packet_loss_discard(tx_sock);
	setup_tx_ring_layout(tx_sock, &tx_ring, size_out, ctx->jumbo);
	create_tx_ring(tx_sock, &tx_ring, ctx->verbose);
	mmap_tx_ring(tx_sock, &tx_ring);
	alloc_tx_ring_frames(&tx_ring);
	bind_tx_ring(tx_sock, &tx_ring, ifindex_out);

	dissector_init_all(ctx->print_mode);

	 if (ctx->promiscuous)
		ifflags = enter_promiscuous_mode(ctx->device_in);

	if (ctx->kpull)
		interval = ctx->kpull;

	set_itimer_interval_value(&itimer, 0, interval);
	setitimer(ITIMER_REAL, &itimer, NULL);

	drop_privileges(ctx->enforce, ctx->uid, ctx->gid);

	printf("Running! Hang up with ^C!\n\n");
	fflush(stdout);

	while (likely(sigint == 0)) {
		while (user_may_pull_from_rx(rx_ring.frames[it_in].iov_base)) {
			__label__ next;

			hdr_in = rx_ring.frames[it_in].iov_base;
			in = ((uint8_t *) hdr_in) + hdr_in->tp_h.tp_mac;

			frame_count++;

			if (ctx->packet_type != -1)
				if (ctx->packet_type != hdr_in->s_ll.sll_pkttype)
					goto next;

			hdr_out = tx_ring.frames[it_out].iov_base;
			out = ((uint8_t *) hdr_out) + TPACKET2_HDRLEN - sizeof(struct sockaddr_ll);

			for (; !user_may_pull_from_tx(tx_ring.frames[it_out].iov_base) &&
			       likely(!sigint);) {
				if (ctx->randomize)
					next_rnd_slot(&it_out, &tx_ring);
				else {
					it_out++;
					if (it_out >= tx_ring.layout.tp_frame_nr)
						it_out = 0;
				}

				hdr_out = tx_ring.frames[it_out].iov_base;
				out = ((uint8_t *) hdr_out) + TPACKET2_HDRLEN - sizeof(struct sockaddr_ll);
			}

			tpacket_hdr_clone(&hdr_out->tp_h, &hdr_in->tp_h);
			fmemcpy(out, in, hdr_in->tp_h.tp_len);

			kernel_may_pull_from_tx(&hdr_out->tp_h);
			if (ctx->randomize)
				next_rnd_slot(&it_out, &tx_ring);
			else {
				it_out++;
				if (it_out >= tx_ring.layout.tp_frame_nr)
					it_out = 0;
			}

			show_frame_hdr(hdr_in, ctx->print_mode);

			dissector_entry_point(in, hdr_in->tp_h.tp_snaplen,
					      ctx->link_type, ctx->print_mode);

			if (frame_count_max != 0) {
				if (frame_count >= frame_count_max) {
					sigint = 1;
					break;
				}
			}

			next:

			kernel_may_pull_from_rx(&hdr_in->tp_h);

			it_in++;
			if (it_in >= rx_ring.layout.tp_frame_nr)
				it_in = 0;

			if (unlikely(sigint == 1))
				goto out;
		}

		poll(&rx_poll, 1, -1);
	}

	out:

	sock_print_net_stats(rx_sock, 0);

	bpf_release(&bpf_ops);

	dissector_cleanup_all();

	destroy_tx_ring(tx_sock, &tx_ring);
	destroy_rx_ring(rx_sock, &rx_ring);

	if (ctx->promiscuous)
		leave_promiscuous_mode(ctx->device_in, ifflags);

	close(tx_sock);
	close(rx_sock);
}