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1 /* -*- Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil; -*- */ |
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2 /* |
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3 * Copyright (c) 2006 INRIA |
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4 * |
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5 * This program is free software; you can redistribute it and/or modify |
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6 * it under the terms of the GNU General Public License version 2 as |
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7 * published by the Free Software Foundation; |
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8 * |
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9 * This program is distributed in the hope that it will be useful, |
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10 * but WITHOUT ANY WARRANTY; without even the implied warranty of |
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11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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12 * GNU General Public License for more details. |
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13 * |
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14 * You should have received a copy of the GNU General Public License |
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15 * along with this program; if not, write to the Free Software |
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16 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
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17 * |
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18 * Author: Mathieu Lacage <mathieu.lacage@sophia.inria.fr> |
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19 */ |
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20 #include "ns3/packet.h" |
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21 #include "ns3/log.h" |
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22 #include "ns3/node.h" |
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23 #include "ns3/net-device.h" |
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24 #include "ns3/object-vector.h" |
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25 #include "ns3/trace-source-accessor.h" |
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26 |
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27 #include "ipv4-l3-protocol.h" |
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28 #include "arp-l3-protocol.h" |
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29 #include "arp-header.h" |
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30 #include "arp-cache.h" |
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31 #include "ipv4-interface.h" |
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32 |
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33 NS_LOG_COMPONENT_DEFINE ("ArpL3Protocol"); |
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34 |
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35 namespace ns3 { |
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36 |
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37 const uint16_t ArpL3Protocol::PROT_NUMBER = 0x0806; |
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38 |
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39 NS_OBJECT_ENSURE_REGISTERED (ArpL3Protocol); |
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40 |
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41 TypeId |
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42 ArpL3Protocol::GetTypeId (void) |
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43 { |
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44 static TypeId tid = TypeId ("ns3::ArpL3Protocol") |
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45 .SetParent<Object> () |
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46 .AddAttribute ("CacheList", |
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47 "The list of ARP caches", |
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48 ObjectVectorValue (), |
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49 MakeObjectVectorAccessor (&ArpL3Protocol::m_cacheList), |
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50 MakeObjectVectorChecker<ArpCache> ()) |
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51 .AddTraceSource ("Drop", |
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52 "Packet dropped because not enough room in pending queue for a specific cache entry.", |
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53 MakeTraceSourceAccessor (&ArpL3Protocol::m_dropTrace)) |
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54 ; |
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55 return tid; |
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56 } |
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57 |
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58 ArpL3Protocol::ArpL3Protocol () |
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59 { |
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60 NS_LOG_FUNCTION (this); |
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61 } |
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62 |
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63 ArpL3Protocol::~ArpL3Protocol () |
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64 { |
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65 NS_LOG_FUNCTION (this); |
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66 } |
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67 |
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68 void |
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69 ArpL3Protocol::SetNode (Ptr<Node> node) |
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70 { |
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71 m_node = node; |
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72 } |
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73 |
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74 void |
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75 ArpL3Protocol::DoDispose (void) |
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76 { |
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77 NS_LOG_FUNCTION (this); |
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78 for (CacheList::iterator i = m_cacheList.begin (); i != m_cacheList.end (); ++i) |
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79 { |
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80 Ptr<ArpCache> cache = *i; |
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81 cache->Dispose (); |
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82 } |
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83 m_cacheList.clear (); |
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84 m_node = 0; |
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85 Object::DoDispose (); |
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86 } |
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87 |
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88 Ptr<ArpCache> |
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89 ArpL3Protocol::CreateCache (Ptr<NetDevice> device, Ptr<Ipv4Interface> interface) |
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90 { |
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91 Ptr<Ipv4L3Protocol> ipv4 = m_node->GetObject<Ipv4L3Protocol> (); |
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92 Ptr<ArpCache> cache = CreateObject<ArpCache> (); |
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93 cache->SetDevice (device, interface); |
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94 NS_ASSERT (device->IsBroadcast ()); |
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95 device->SetLinkChangeCallback (MakeCallback (&ArpCache::Flush, cache)); |
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96 m_cacheList.push_back (cache); |
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97 return cache; |
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98 } |
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99 |
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100 Ptr<ArpCache> |
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101 ArpL3Protocol::FindCache (Ptr<NetDevice> device) |
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102 { |
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103 NS_LOG_FUNCTION_NOARGS (); |
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104 for (CacheList::const_iterator i = m_cacheList.begin (); i != m_cacheList.end (); i++) |
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105 { |
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106 if ((*i)->GetDevice () == device) |
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107 { |
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108 return *i; |
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109 } |
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110 } |
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111 NS_ASSERT (false); |
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112 // quiet compiler |
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113 return 0; |
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114 } |
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115 |
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116 void |
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117 ArpL3Protocol::Receive(Ptr<NetDevice> device, Ptr<Packet> packet, uint16_t protocol, const Address &from) |
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118 { |
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119 NS_LOG_FUNCTION_NOARGS (); |
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120 Ptr<ArpCache> cache = FindCache (device); |
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121 ArpHeader arp; |
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122 packet->RemoveHeader (arp); |
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123 |
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124 NS_LOG_LOGIC ("ARP: received "<< (arp.IsRequest ()? "request" : "reply") << |
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125 " node="<<m_node->GetId ()<<", got request from " << |
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126 arp.GetSourceIpv4Address () << " for address " << |
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127 arp.GetDestinationIpv4Address () << "; we have address " << |
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128 cache->GetInterface ()->GetAddress ()); |
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129 |
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130 /** |
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131 * Note: we do not update the ARP cache when we receive an ARP request |
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132 * from an unknown node. See bug #107 |
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133 */ |
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134 |
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135 if (arp.IsRequest () && |
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136 arp.GetDestinationIpv4Address () == cache->GetInterface ()->GetAddress ()) |
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137 { |
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138 NS_LOG_LOGIC ("node="<<m_node->GetId () <<", got request from " << |
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139 arp.GetSourceIpv4Address () << " -- send reply"); |
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140 SendArpReply (cache, arp.GetSourceIpv4Address (), |
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141 arp.GetSourceHardwareAddress ()); |
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142 } |
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143 else if (arp.IsReply () && |
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144 arp.GetDestinationIpv4Address ().IsEqual (cache->GetInterface ()->GetAddress ()) && |
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145 arp.GetDestinationHardwareAddress () == device->GetAddress ()) |
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146 { |
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147 Ipv4Address from = arp.GetSourceIpv4Address (); |
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148 ArpCache::Entry *entry = cache->Lookup (from); |
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149 if (entry != 0) |
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150 { |
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151 if (entry->IsWaitReply ()) |
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152 { |
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153 NS_LOG_LOGIC ("node="<<m_node->GetId ()<<", got reply from " << |
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154 arp.GetSourceIpv4Address () |
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155 << " for waiting entry -- flush"); |
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156 Address from_mac = arp.GetSourceHardwareAddress (); |
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157 entry->MarkAlive (from_mac); |
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158 Ptr<Packet> pending = entry->DequeuePending(); |
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159 while (pending != 0) |
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160 { |
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161 cache->GetInterface ()->Send (pending, |
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162 arp.GetSourceIpv4Address ()); |
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163 pending = entry->DequeuePending(); |
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164 } |
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165 } |
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166 else |
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167 { |
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168 // ignore this reply which might well be an attempt |
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169 // at poisening my arp cache. |
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170 NS_LOG_LOGIC("node="<<m_node->GetId ()<<", got reply from " << |
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171 arp.GetSourceIpv4Address () << |
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172 " for non-waiting entry -- drop"); |
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173 m_dropTrace (packet); |
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174 } |
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175 } |
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176 else |
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177 { |
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178 NS_LOG_LOGIC ("node="<<m_node->GetId ()<<", got reply for unknown entry -- drop"); |
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179 m_dropTrace (packet); |
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180 } |
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181 } |
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182 else |
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183 { |
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184 NS_LOG_LOGIC ("node="<<m_node->GetId ()<<", got request from " << |
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185 arp.GetSourceIpv4Address () << " for unknown address " << |
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186 arp.GetDestinationIpv4Address () << " -- drop"); |
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187 } |
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188 } |
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189 bool |
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190 ArpL3Protocol::Lookup (Ptr<Packet> packet, Ipv4Address destination, |
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191 Ptr<NetDevice> device, |
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192 Ptr<ArpCache> cache, |
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193 Address *hardwareDestination) |
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194 { |
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195 NS_LOG_FUNCTION_NOARGS (); |
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196 ArpCache::Entry *entry = cache->Lookup (destination); |
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197 if (entry != 0) |
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198 { |
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199 if (entry->IsExpired ()) |
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200 { |
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201 if (entry->IsDead ()) |
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202 { |
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203 NS_LOG_LOGIC ("node="<<m_node->GetId ()<< |
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204 ", dead entry for " << destination << " expired -- send arp request"); |
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205 entry->MarkWaitReply (packet); |
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206 SendArpRequest (cache, destination); |
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207 } |
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208 else if (entry->IsAlive ()) |
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209 { |
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210 NS_LOG_LOGIC ("node="<<m_node->GetId ()<< |
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211 ", alive entry for " << destination << " expired -- send arp request"); |
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212 entry->MarkWaitReply (packet); |
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213 SendArpRequest (cache, destination); |
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214 } |
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215 else if (entry->IsWaitReply ()) |
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216 { |
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217 NS_LOG_LOGIC ("node="<<m_node->GetId ()<< |
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218 ", wait reply for " << destination << " expired -- drop"); |
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219 entry->MarkDead (); |
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220 Ptr<Packet> pending = entry->DequeuePending(); |
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221 while (pending != 0) |
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222 { |
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223 m_dropTrace (pending); |
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224 pending = entry->DequeuePending(); |
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225 } |
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226 m_dropTrace (packet); |
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227 } |
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228 } |
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229 else |
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230 { |
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231 if (entry->IsDead ()) |
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232 { |
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233 NS_LOG_LOGIC ("node="<<m_node->GetId ()<< |
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234 ", dead entry for " << destination << " valid -- drop"); |
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235 m_dropTrace (packet); |
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236 } |
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237 else if (entry->IsAlive ()) |
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238 { |
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239 NS_LOG_LOGIC ("node="<<m_node->GetId ()<< |
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240 ", alive entry for " << destination << " valid -- send"); |
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241 *hardwareDestination = entry->GetMacAddress (); |
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242 return true; |
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243 } |
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244 else if (entry->IsWaitReply ()) |
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245 { |
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246 NS_LOG_LOGIC ("node="<<m_node->GetId ()<< |
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247 ", wait reply for " << destination << " valid -- drop previous"); |
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248 if (!entry->UpdateWaitReply (packet)) |
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249 { |
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250 m_dropTrace (packet); |
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251 } |
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252 } |
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253 } |
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254 } |
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255 else |
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256 { |
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257 // This is our first attempt to transmit data to this destination. |
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258 NS_LOG_LOGIC ("node="<<m_node->GetId ()<< |
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259 ", no entry for " << destination << " -- send arp request"); |
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260 entry = cache->Add (destination); |
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261 entry->MarkWaitReply (packet); |
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262 SendArpRequest (cache, destination); |
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263 } |
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264 return false; |
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265 } |
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266 |
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267 void |
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268 ArpL3Protocol::SendArpRequest (Ptr<const ArpCache> cache, Ipv4Address to) |
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269 { |
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270 NS_LOG_FUNCTION_NOARGS (); |
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271 ArpHeader arp; |
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272 NS_LOG_LOGIC ("ARP: sending request from node "<<m_node->GetId ()<< |
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273 " || src: " << cache->GetDevice ()->GetAddress () << |
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274 " / " << cache->GetInterface ()->GetAddress () << |
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275 " || dst: " << cache->GetDevice ()->GetBroadcast () << |
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276 " / " << to); |
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277 arp.SetRequest (cache->GetDevice ()->GetAddress (), |
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278 cache->GetInterface ()->GetAddress (), |
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279 cache->GetDevice ()->GetBroadcast (), |
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280 to); |
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281 Ptr<Packet> packet = Create<Packet> (); |
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282 packet->AddHeader (arp); |
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283 cache->GetDevice ()->Send (packet, cache->GetDevice ()->GetBroadcast (), PROT_NUMBER); |
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284 } |
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285 |
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286 void |
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287 ArpL3Protocol::SendArpReply (Ptr<const ArpCache> cache, Ipv4Address toIp, Address toMac) |
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288 { |
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289 NS_LOG_FUNCTION_NOARGS (); |
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290 ArpHeader arp; |
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291 NS_LOG_LOGIC ("ARP: sending reply from node "<<m_node->GetId ()<< |
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292 "|| src: " << cache->GetDevice ()->GetAddress () << |
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293 " / " << cache->GetInterface ()->GetAddress () << |
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294 " || dst: " << toMac << " / " << toIp); |
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295 arp.SetReply (cache->GetDevice ()->GetAddress (), |
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296 cache->GetInterface ()->GetAddress (), |
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297 toMac, toIp); |
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298 Ptr<Packet> packet = Create<Packet> (); |
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299 packet->AddHeader (arp); |
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300 cache->GetDevice ()->Send (packet, toMac, PROT_NUMBER); |
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301 } |
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302 |
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303 }//namespace ns3 |