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+/*
+ * Copyright (c) 2003 The Regents of The University of Michigan
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met: redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer;
+ * redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution;
+ * neither the name of the copyright holders nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/* @file
+ * Interface to connect a simulated ethernet device to the real world
+ */
+
+#if defined(__OpenBSD__)
+#include <sys/param.h>
+#endif
+#include <netinet/in.h>
+
+#include <unistd.h>
+
+#include <deque>
+#include <string>
+
+#include "etherdump.hh"
+#include "etherint.hh"
+#include "etherpkt.hh"
+#include "ethertap.hh"
+#include "pollevent.hh"
+#include "socket.hh"
+#include "trace.hh"
+#include "misc.hh"
+
+using namespace std;
+
+/**
+ */
+class TapListener
+{
+ protected:
+ /**
+ */
+ class Event : public PollEvent
+ {
+ protected:
+ TapListener *listener;
+
+ public:
+ Event(TapListener *l, int fd, int e)
+ : PollEvent(fd, e), listener(l) {}
+
+ virtual void process(int revent) { listener->accept(); }
+ };
+
+ friend class Event;
+ Event *event;
+
+ protected:
+ ListenSocket listener;
+ EtherTap *tap;
+ int port;
+
+ public:
+ TapListener(EtherTap *t, int p)
+ : event(NULL), tap(t), port(p) {}
+ ~TapListener() { if (event) delete event; }
+
+ void accept();
+ void listen();
+};
+
+void
+TapListener::listen()
+{
+ while (!listener.listen(port, true)) {
+ DPRINTF(Ethernet, "TapListener(listen): Can't bind port %d\n", port);
+ port++;
+ }
+
+ ccprintf(cerr, "Listening for tap connection on port %d\n", port);
+ event = new Event(this, listener.getfd(), POLLIN|POLLERR);
+ pollQueue.schedule(event);
+}
+
+void
+TapListener::accept()
+{
+ if (!listener.islistening())
+ panic("TapListener(accept): cannot accept if we're not listening!");
+
+ int sfd = listener.accept(true);
+ if (sfd != -1)
+ tap->attach(sfd);
+}
+
+/**
+ */
+class TapEvent : public PollEvent
+{
+ protected:
+ EtherTap *tap;
+
+ public:
+ TapEvent(EtherTap *_tap, int fd, int e)
+ : PollEvent(fd, e), tap(_tap) {}
+ virtual void process(int revent) { tap->process(revent); }
+};
+
+EtherTap::EtherTap(const string &name, EtherDump *d, int port, int bufsz)
+ : EtherInt(name), event(NULL), socket(-1), buflen(bufsz), dump(d),
+ txEvent(this)
+{
+ buffer = new char[buflen];
+ listener = new TapListener(this, port);
+ listener->listen();
+}
+
+EtherTap::~EtherTap()
+{
+ if (event)
+ delete event;
+ if (buffer)
+ delete [] buffer;
+
+ delete listener;
+}
+
+void
+EtherTap::attach(int fd)
+{
+ if (socket != -1)
+ close(fd);
+
+ buffer_offset = 0;
+ data_len = 0;
+ socket = fd;
+ DPRINTF(Ethernet, "EtherTap attached\n");
+ event = new TapEvent(this, socket, POLLIN|POLLERR);
+ pollQueue.schedule(event);
+}
+
+void
+EtherTap::detach()
+{
+ DPRINTF(Ethernet, "EtherTap detached\n");
+ delete event;
+ close(socket);
+ socket = -1;
+}
+
+bool
+EtherTap::recvPacket(PacketPtr packet)
+{
+ if (dump)
+ dump->dump(packet);
+
+ DPRINTF(Ethernet, "EtherTap output len=%d\n", packet->length);
+ DDUMP(EthernetData, packet->data, packet->length);
+ u_int32_t len = htonl(packet->length);
+ write(socket, &len, sizeof(len));
+ write(socket, packet->data, packet->length);
+
+ recvDone();
+
+ return true;
+}
+
+void
+EtherTap::sendDone()
+{}
+
+void
+EtherTap::process(int revent)
+{
+ if (revent & POLLERR) {
+ detach();
+ return;
+ }
+
+ char *data = buffer + sizeof(u_int32_t);
+ if (!(revent & POLLIN))
+ return;
+
+ if (buffer_offset < data_len + sizeof(u_int32_t)) {
+ int len = read(socket, buffer + buffer_offset, buflen - buffer_offset);
+ if (len == 0) {
+ detach();
+ return;
+ }
+
+ buffer_offset += len;
+
+ if (data_len == 0)
+ data_len = ntohl(*(u_int32_t *)buffer);
+
+ DPRINTF(Ethernet, "Received data from peer: len=%d buffer_offset=%d "
+ "data_len=%d\n", len, buffer_offset, data_len);
+ }
+
+ while (data_len != 0 && buffer_offset >= data_len + sizeof(u_int32_t)) {
+ PacketPtr packet;
+ packet = new EtherPacket;
+ packet->data = new uint8_t[data_len];
+ packet->length = data_len;
+ memcpy(packet->data, data, data_len);
+
+ buffer_offset -= data_len + sizeof(u_int32_t);
+ assert(buffer_offset >= 0);
+ if (buffer_offset > 0) {
+ memmove(buffer, data + data_len, buffer_offset);
+ data_len = ntohl(*(u_int32_t *)buffer);
+ } else
+ data_len = 0;
+
+ DPRINTF(Ethernet, "EtherTap input len=%d\n", packet->length);
+ DDUMP(EthernetData, packet->data, packet->length);
+ if (!sendPacket(packet)) {
+ DPRINTF(Ethernet, "bus busy...buffer for retransmission\n");
+ packetBuffer.push(packet);
+ if (!txEvent.scheduled())
+ txEvent.schedule(curTick + 1000);
+ } else if (dump)
+ dump->dump(packet);
+ }
+}
+
+void
+EtherTap::retransmit()
+{
+ if (packetBuffer.empty())
+ return;
+
+ PacketPtr packet = packetBuffer.front();
+ if (sendPacket(packet)) {
+ if (dump)
+ dump->dump(packet);
+ DPRINTF(Ethernet, "EtherTap retransmit\n");
+ packetBuffer.front() = NULL;
+ packetBuffer.pop();
+ }
+
+ if (!packetBuffer.empty() && !txEvent.scheduled())
+ txEvent.schedule(curTick + 1000);
+}
+
+BEGIN_DECLARE_SIM_OBJECT_PARAMS(EtherTap)
+
+ SimObjectParam<EtherInt *> peer;
+ SimObjectParam<EtherDump *> packet_dump;
+ Param<uint16_t> port;
+ Param<uint16_t> bufsz;
+
+END_DECLARE_SIM_OBJECT_PARAMS(EtherTap)
+
+BEGIN_INIT_SIM_OBJECT_PARAMS(EtherTap)
+
+ INIT_PARAM_DFLT(peer, "peer interface", NULL),
+ INIT_PARAM_DFLT(packet_dump, "object to dump network packets to", NULL),
+ INIT_PARAM_DFLT(port, "tap port", 3500),
+ INIT_PARAM_DFLT(bufsz, "tap buffer size", 10000)
+
+END_INIT_SIM_OBJECT_PARAMS(EtherTap)
+
+
+CREATE_SIM_OBJECT(EtherTap)
+{
+ EtherTap *tap = new EtherTap(getInstanceName(), packet_dump, port, bufsz);
+
+ if (peer) {
+ tap->setPeer(peer);
+ peer->setPeer(tap);
+ }
+
+ return tap;
+}
+
+REGISTER_SIM_OBJECT("EtherTap", EtherTap)
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