src/modules/m_spanningtree/treesocket1.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  InspIRCd: (C) 2002-2008 InspIRCd Development Team
   6  * See: http://www.inspircd.org/wiki/index.php/Credits
   7  *
   8  * This program is free but copyrighted software; see
   9  *            the file COPYING for details.
  10  *
  11  * ---------------------------------------------------
  12  */
  13
  14 #include "inspircd.h"
  15 #include "commands/cmd_whois.h"
  16 #include "commands/cmd_stats.h"
  17 #include "socket.h"
  18 #include "xline.h"
  19 #include "transport.h"
  20 #include "m_hash.h"
  21 #include "socketengine.h"
  22
  23 #include "m_spanningtree/main.h"
  24 #include "m_spanningtree/utils.h"
  25 #include "m_spanningtree/treeserver.h"
  26 #include "m_spanningtree/link.h"
  27 #include "m_spanningtree/treesocket.h"
  28 #include "m_spanningtree/resolvers.h"
  29 #include "m_spanningtree/handshaketimer.h"
  30
  31 /* $ModDep: m_spanningtree/resolvers.h m_spanningtree/main.h m_spanningtree/utils.h m_spanningtree/treeserver.h m_spanningtree/link.h m_spanningtree/treesocket.h m_hash.h m_spanningtree/handshaketimer.h */
  32
  33
  34 /** Because most of the I/O gubbins are encapsulated within
  35  * BufferedSocket, we just call the superclass constructor for
  36  * most of the action, and append a few of our own values
  37  * to it.
  38  */
  39 TreeSocket::TreeSocket(SpanningTreeUtilities* Util, InspIRCd* SI, std::string shost, int iport, bool listening, unsigned long maxtime, Module* HookMod)
  40         : BufferedSocket(SI, shost, iport, listening, maxtime), Utils(Util), Hook(HookMod)
  41 {
  42         myhost = host;
  43         this->LinkState = LISTENER;
  44         theirchallenge.clear();
  45         ourchallenge.clear();
  46         if (listening && Hook)
  47                 BufferedSocketHookRequest(this, (Module*)Utils->Creator, Hook).Send();
  48 }
  49
  50 TreeSocket::TreeSocket(SpanningTreeUtilities* Util, InspIRCd* SI, std::string shost, int iport, bool listening, unsigned long maxtime, const std::string &ServerName, const std::string &bindto, Module* HookMod)
  51         : BufferedSocket(SI, shost, iport, listening, maxtime, bindto), Utils(Util), Hook(HookMod)
  52 {
  53         myhost = ServerName;
  54         theirchallenge.clear();
  55         ourchallenge.clear();
  56         this->LinkState = CONNECTING;
  57         if (Hook)
  58                 BufferedSocketHookRequest(this, (Module*)Utils->Creator, Hook).Send();
  59 }
  60
  61 /** When a listening socket gives us a new file descriptor,
  62  * we must associate it with a socket without creating a new
  63  * connection. This constructor is used for this purpose.
  64  */
  65 TreeSocket::TreeSocket(SpanningTreeUtilities* Util, InspIRCd* SI, int newfd, char* ip, Module* HookMod)
  66         : BufferedSocket(SI, newfd, ip), Utils(Util), Hook(HookMod)
  67 {
  68         this->LinkState = WAIT_AUTH_1;
  69         theirchallenge.clear();
  70         ourchallenge.clear();
  71         sentcapab = false;
  72         /* If we have a transport module hooked to the parent, hook the same module to this
  73          * socket, and set a timer waiting for handshake before we send CAPAB etc.
  74          */
  75         if (Hook)
  76                 BufferedSocketHookRequest(this, (Module*)Utils->Creator, Hook).Send();
  77
  78         Instance->Timers->AddTimer(new HandshakeTimer(Instance, this, &(Utils->LinkBlocks[0]), this->Utils, 1));
  79 }
  80
  81 ServerState TreeSocket::GetLinkState()
  82 {
  83         return this->LinkState;
  84 }
  85
  86 Module* TreeSocket::GetHook()
  87 {
  88         return this->Hook;
  89 }
  90
  91 TreeSocket::~TreeSocket()
  92 {
  93         if (Hook)
  94                 BufferedSocketUnhookRequest(this, (Module*)Utils->Creator, Hook).Send();
  95 }
  96
  97 /** When an outbound connection finishes connecting, we receive
  98  * this event, and must send our SERVER string to the other
  99  * side. If the other side is happy, as outlined in the server
 100  * to server docs on the inspircd.org site, the other side
 101  * will then send back its own server string.
 102  */
 103 bool TreeSocket::OnConnected()
 104 {
 105         if (this->LinkState == CONNECTING)
 106         {
 107                 /* we do not need to change state here. */
 108                 for (std::vector<Link>::iterator x = Utils->LinkBlocks.begin(); x < Utils->LinkBlocks.end(); x++)
 109                 {
 110                         if (x->Name == this->myhost)
 111                         {
 112                                 Utils->Creator->RemoteMessage(NULL,"Connection to \2%s\2[%s] started.", myhost.c_str(), (x->HiddenFromStats ? "<hidden>" : this->GetIP().c_str()));
 113                                 if (Hook)
 114                                 {
 115                                         BufferedSocketHookRequest(this, (Module*)Utils->Creator, Hook).Send();
 116                                         Utils->Creator->RemoteMessage(NULL,"Connection to \2%s\2[%s] using transport \2%s\2", myhost.c_str(), (x->HiddenFromStats ? "<hidden>" : this->GetIP().c_str()),
 117                                                         x->Hook.c_str());
 118                                 }
 119                                 this->OutboundPass = x->SendPass;
 120                                 sentcapab = false;
 121
 122                                 /* found who we're supposed to be connecting to, send the neccessary gubbins. */
 123                                 if (this->GetHook())
 124                                         Instance->Timers->AddTimer(new HandshakeTimer(Instance, this, &(*x), this->Utils, 1));
 125                                 else
 126                                         this->SendCapabilities();
 127
 128                                 return true;
 129                         }
 130                 }
 131         }
 132         /* There is a (remote) chance that between the /CONNECT and the connection
 133          * being accepted, some muppet has removed the <link> block and rehashed.
 134          * If that happens the connection hangs here until it's closed. Unlikely
 135          * and rather harmless.
 136          */
 137         this->Utils->Creator->RemoteMessage(NULL,"Connection to \2%s\2 lost link tag(!)", myhost.c_str());
 138         return true;
 139 }
 140
 141 void TreeSocket::OnError(BufferedSocketError e)
 142 {
 143         Link* MyLink;
 144
 145         if (this->LinkState == LISTENER)
 146                 return;
 147
 148         switch (e)
 149         {
 150                 case I_ERR_CONNECT:
 151                         Utils->Creator->RemoteMessage(NULL,"Connection failed: Connection to \002%s\002 refused", myhost.c_str());
 152                         MyLink = Utils->FindLink(myhost);
 153                         if (MyLink)
 154                                 Utils->DoFailOver(MyLink);
 155                 break;
 156                 case I_ERR_SOCKET:
 157                         Utils->Creator->RemoteMessage(NULL,"Connection failed: Could not create socket (%s)", strerror(errno));
 158                 break;
 159                 case I_ERR_BIND:
 160                         Utils->Creator->RemoteMessage(NULL,"Connection failed: Error binding socket to address or port (%s)", strerror(errno));
 161                 break;
 162                 case I_ERR_WRITE:
 163                         Utils->Creator->RemoteMessage(NULL,"Connection failed: I/O error on connection (%s)", strerror(errno));
 164                 break;
 165                 case I_ERR_NOMOREFDS:
 166                         Utils->Creator->RemoteMessage(NULL,"Connection failed: Operating system is out of file descriptors!");
 167                 break;
 168                 default:
 169                         if ((errno) && (errno != EINPROGRESS) && (errno != EAGAIN))
 170                                 Utils->Creator->RemoteMessage(NULL,"Connection to \002%s\002 failed with OS error: %s", myhost.c_str(), strerror(errno));
 171                 break;
 172         }
 173 }
 174
 175 int TreeSocket::OnDisconnect()
 176 {
 177         /* For the same reason as above, we don't
 178          * handle OnDisconnect()
 179          */
 180         return true;
 181 }
 182
 183 void TreeSocket::SendError(const std::string &errormessage)
 184 {
 185         /* Display the error locally as well as sending it remotely */
 186         Utils->Creator->RemoteMessage(NULL, "Sent \2ERROR\2 to %s: %s", (this->InboundServerName.empty() ? this->GetIP().c_str() : this->InboundServerName.c_str()), errormessage.c_str());
 187         this->WriteLine("ERROR :"+errormessage);
 188         /* One last attempt to make sure the error reaches its target */
 189         this->FlushWriteBuffer();
 190 }
 191
 192 /** This function forces this server to quit, removing this server
 193  * and any users on it (and servers and users below that, etc etc).
 194  * It's very slow and pretty clunky, but luckily unless your network
 195  * is having a REAL bad hair day, this function shouldnt be called
 196  * too many times a month ;-)
 197  */
 198 void TreeSocket::SquitServer(std::string &from, TreeServer* Current)
 199 {
 200         /* recursively squit the servers attached to 'Current'.
 201          * We're going backwards so we don't remove users
 202          * while we still need them ;)
 203          */
 204         for (unsigned int q = 0; q < Current->ChildCount(); q++)
 205         {
 206                 TreeServer* recursive_server = Current->GetChild(q);
 207                 this->SquitServer(from,recursive_server);
 208         }
 209         /* Now we've whacked the kids, whack self */
 210         num_lost_servers++;
 211         num_lost_users += Current->QuitUsers(from);
 212 }
 213
 214 /** This is a wrapper function for SquitServer above, which
 215  * does some validation first and passes on the SQUIT to all
 216  * other remaining servers.
 217  */
 218 void TreeSocket::Squit(TreeServer* Current, const std::string &reason)
 219 {
 220         if ((Current) && (Current != Utils->TreeRoot))
 221         {
 222                 Event rmode((char*)Current->GetName().c_str(), (Module*)Utils->Creator, "lost_server");
 223                 rmode.Send(Instance);
 224
 225                 std::deque<std::string> params;
 226                 params.push_back(Current->GetName());
 227                 params.push_back(":"+reason);
 228                 Utils->DoOneToAllButSender(Current->GetParent()->GetName(),"SQUIT",params,Current->GetName());
 229                 if (Current->GetParent() == Utils->TreeRoot)
 230                 {
 231                         this->Instance->SNO->WriteToSnoMask('l',"Server \002"+Current->GetName()+"\002 split: "+reason);
 232                 }
 233                 else
 234                 {
 235                         this->Instance->SNO->WriteToSnoMask('l',"Server \002"+Current->GetName()+"\002 split from server \002"+Current->GetParent()->GetName()+"\002 with reason: "+reason);
 236                 }
 237                 num_lost_servers = 0;
 238                 num_lost_users = 0;
 239                 std::string from = Current->GetParent()->GetName()+" "+Current->GetName();
 240                 SquitServer(from, Current);
 241                 Current->Tidy();
 242                 Current->GetParent()->DelChild(Current);
 243                 delete Current;
 244                 this->Instance->SNO->WriteToSnoMask('l',"Netsplit complete, lost \002%d\002 users on \002%d\002 servers.", num_lost_users, num_lost_servers);
 245         }
 246         else
 247                 Instance->Logs->Log("m_spanningtree",DEFAULT,"Squit from unknown server");
 248 }
 249
 250 /** This function is called when we receive data from a remote
 251  * server. We buffer the data in a std::string (it doesnt stay
 252  * there for long), reading using BufferedSocket::Read() which can
 253  * read up to 16 kilobytes in one operation.
 254  *
 255  * IF THIS FUNCTION RETURNS FALSE, THE CORE CLOSES AND DELETES
 256  * THE SOCKET OBJECT FOR US.
 257  */
 258 bool TreeSocket::OnDataReady()
 259 {
 260         const char* data = this->Read();
 261         /* Check that the data read is a valid pointer and it has some content */
 262         if (data && *data)
 263         {
 264                 this->in_buffer.append(data);
 265                 /* While there is at least one new line in the buffer,
 266                  * do something useful (we hope!) with it.
 267                  */
 268                 while (in_buffer.find("\n") != std::string::npos)
 269                 {
 270                         std::string ret = in_buffer.substr(0,in_buffer.find("\n")-1);
 271                         in_buffer = in_buffer.substr(in_buffer.find("\n")+1,in_buffer.length()-in_buffer.find("\n"));
 272                         /* Use rfind here not find, as theres more
 273                          * chance of the \r being near the end of the
 274                          * string, not the start.
 275                          */
 276                         if (ret.find("\r") != std::string::npos)
 277                                 ret = in_buffer.substr(0,in_buffer.find("\r")-1);
 278                         /* Process this one, abort if it
 279                          * didnt return true.
 280                          */
 281                         if (!this->ProcessLine(ret))
 282                         {
 283                                 return false;
 284                         }
 285                 }
 286                 return true;
 287         }
 288         /* EAGAIN returns an empty but non-NULL string, so this
 289          * evaluates to TRUE for EAGAIN but to FALSE for EOF.
 290          */
 291         return (data && !*data);
 292 }