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 "wildcard.h"
  19 #include "xline.h"
  20 #include "transport.h"
  21 #include "m_hash.h"
  22 #include "socketengine.h"
  23
  24 #include "m_spanningtree/main.h"
  25 #include "m_spanningtree/utils.h"
  26 #include "m_spanningtree/treeserver.h"
  27 #include "m_spanningtree/link.h"
  28 #include "m_spanningtree/treesocket.h"
  29 #include "m_spanningtree/resolvers.h"
  30 #include "m_spanningtree/handshaketimer.h"
  31
  32 /* $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 */
  33
  34
  35 /** Because most of the I/O gubbins are encapsulated within
  36  * BufferedSocket, we just call the superclass constructor for
  37  * most of the action, and append a few of our own values
  38  * to it.
  39  */
  40 TreeSocket::TreeSocket(SpanningTreeUtilities* Util, InspIRCd* SI, std::string shost, int iport, bool listening, unsigned long maxtime, Module* HookMod)
  41         : BufferedSocket(SI, shost, iport, listening, maxtime), Utils(Util), Hook(HookMod)
  42 {
  43         myhost = host;
  44         this->LinkState = LISTENER;
  45         theirchallenge.clear();
  46         ourchallenge.clear();
  47         if (listening && Hook)
  48                 BufferedSocketHookRequest(this, (Module*)Utils->Creator, Hook).Send();
  49 }
  50
  51 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)
  52         : BufferedSocket(SI, shost, iport, listening, maxtime, bindto), Utils(Util), Hook(HookMod)
  53 {
  54         myhost = ServerName;
  55         theirchallenge.clear();
  56         ourchallenge.clear();
  57         this->LinkState = CONNECTING;
  58         if (Hook)
  59                 BufferedSocketHookRequest(this, (Module*)Utils->Creator, Hook).Send();
  60 }
  61
  62 /** When a listening socket gives us a new file descriptor,
  63  * we must associate it with a socket without creating a new
  64  * connection. This constructor is used for this purpose.
  65  */
  66 TreeSocket::TreeSocket(SpanningTreeUtilities* Util, InspIRCd* SI, int newfd, char* ip, Module* HookMod)
  67         : BufferedSocket(SI, newfd, ip), Utils(Util), Hook(HookMod)
  68 {
  69         this->LinkState = WAIT_AUTH_1;
  70         theirchallenge.clear();
  71         ourchallenge.clear();
  72         sentcapab = false;
  73         /* If we have a transport module hooked to the parent, hook the same module to this
  74          * socket, and set a timer waiting for handshake before we send CAPAB etc.
  75          */
  76         if (Hook)
  77                 BufferedSocketHookRequest(this, (Module*)Utils->Creator, Hook).Send();
  78
  79         Instance->Timers->AddTimer(new HandshakeTimer(Instance, this, &(Utils->LinkBlocks[0]), this->Utils, 1));
  80 }
  81
  82 ServerState TreeSocket::GetLinkState()
  83 {
  84         return this->LinkState;
  85 }
  86
  87 Module* TreeSocket::GetHook()
  88 {
  89         return this->Hook;
  90 }
  91
  92 TreeSocket::~TreeSocket()
  93 {
  94         if (Hook)
  95                 BufferedSocketUnhookRequest(this, (Module*)Utils->Creator, Hook).Send();
  96 }
  97
  98 /** When an outbound connection finishes connecting, we receive
  99  * this event, and must send our SERVER string to the other
 100  * side. If the other side is happy, as outlined in the server
 101  * to server docs on the inspircd.org site, the other side
 102  * will then send back its own server string.
 103  */
 104 bool TreeSocket::OnConnected()
 105 {
 106         if (this->LinkState == CONNECTING)
 107         {
 108                 /* we do not need to change state here. */
 109                 for (std::vector<Link>::iterator x = Utils->LinkBlocks.begin(); x < Utils->LinkBlocks.end(); x++)
 110                 {
 111                         if (x->Name == this->myhost)
 112                         {
 113                                 Utils->Creator->RemoteMessage(NULL,"Connection to \2%s\2[%s] started.", myhost.c_str(), (x->HiddenFromStats ? "<hidden>" : this->GetIP().c_str()));
 114                                 if (Hook)
 115                                 {
 116                                         BufferedSocketHookRequest(this, (Module*)Utils->Creator, Hook).Send();
 117                                         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()),
 118                                                         x->Hook.c_str());
 119                                 }
 120                                 this->OutboundPass = x->SendPass;
 121                                 sentcapab = false;
 122
 123                                 /* found who we're supposed to be connecting to, send the neccessary gubbins. */
 124                                 if (this->GetHook())
 125                                         Instance->Timers->AddTimer(new HandshakeTimer(Instance, this, &(*x), this->Utils, 1));
 126                                 else
 127                                         this->SendCapabilities();
 128
 129                                 return true;
 130                         }
 131                 }
 132         }
 133         /* There is a (remote) chance that between the /CONNECT and the connection
 134          * being accepted, some muppet has removed the <link> block and rehashed.
 135          * If that happens the connection hangs here until it's closed. Unlikely
 136          * and rather harmless.
 137          */
 138         this->Utils->Creator->RemoteMessage(NULL,"Connection to \2%s\2 lost link tag(!)", myhost.c_str());
 139         return true;
 140 }
 141
 142 void TreeSocket::OnError(BufferedSocketError e)
 143 {
 144         Link* MyLink;
 145
 146         if (this->LinkState == LISTENER)
 147                 return;
 148
 149         switch (e)
 150         {
 151                 case I_ERR_CONNECT:
 152                         Utils->Creator->RemoteMessage(NULL,"Connection failed: Connection to \002%s\002 refused", myhost.c_str());
 153                         MyLink = Utils->FindLink(myhost);
 154                         if (MyLink)
 155                                 Utils->DoFailOver(MyLink);
 156                 break;
 157                 case I_ERR_SOCKET:
 158                         Utils->Creator->RemoteMessage(NULL,"Connection failed: Could not create socket (%s)", strerror(errno));
 159                 break;
 160                 case I_ERR_BIND:
 161                         Utils->Creator->RemoteMessage(NULL,"Connection failed: Error binding socket to address or port (%s)", strerror(errno));
 162                 break;
 163                 case I_ERR_WRITE:
 164                         Utils->Creator->RemoteMessage(NULL,"Connection failed: I/O error on connection (%s)", strerror(errno));
 165                 break;
 166                 case I_ERR_NOMOREFDS:
 167                         Utils->Creator->RemoteMessage(NULL,"Connection failed: Operating system is out of file descriptors!");
 168                 break;
 169                 default:
 170                         if ((errno) && (errno != EINPROGRESS) && (errno != EAGAIN))
 171                                 Utils->Creator->RemoteMessage(NULL,"Connection to \002%s\002 failed with OS error: %s", myhost.c_str(), strerror(errno));
 172                 break;
 173         }
 174 }
 175
 176 int TreeSocket::OnDisconnect()
 177 {
 178         /* For the same reason as above, we don't
 179          * handle OnDisconnect()
 180          */
 181         return true;
 182 }
 183
 184 void TreeSocket::SendError(const std::string &errormessage)
 185 {
 186         /* Display the error locally as well as sending it remotely */
 187         Utils->Creator->RemoteMessage(NULL, "Sent \2ERROR\2 to %s: %s", (this->InboundServerName.empty() ? this->GetIP().c_str() : this->InboundServerName.c_str()), errormessage.c_str());
 188         this->WriteLine("ERROR :"+errormessage);
 189         /* One last attempt to make sure the error reaches its target */
 190         this->FlushWriteBuffer();
 191 }
 192
 193 /** This function forces this server to quit, removing this server
 194  * and any users on it (and servers and users below that, etc etc).
 195  * It's very slow and pretty clunky, but luckily unless your network
 196  * is having a REAL bad hair day, this function shouldnt be called
 197  * too many times a month ;-)
 198  */
 199 void TreeSocket::SquitServer(std::string &from, TreeServer* Current)
 200 {
 201         /* recursively squit the servers attached to 'Current'.
 202          * We're going backwards so we don't remove users
 203          * while we still need them ;)
 204          */
 205         for (unsigned int q = 0; q < Current->ChildCount(); q++)
 206         {
 207                 TreeServer* recursive_server = Current->GetChild(q);
 208                 this->SquitServer(from,recursive_server);
 209         }
 210         /* Now we've whacked the kids, whack self */
 211         num_lost_servers++;
 212         num_lost_users += Current->QuitUsers(from);
 213 }
 214
 215 /** This is a wrapper function for SquitServer above, which
 216  * does some validation first and passes on the SQUIT to all
 217  * other remaining servers.
 218  */
 219 void TreeSocket::Squit(TreeServer* Current, const std::string &reason)
 220 {
 221         if ((Current) && (Current != Utils->TreeRoot))
 222         {
 223                 Event rmode((char*)Current->GetName().c_str(), (Module*)Utils->Creator, "lost_server");
 224                 rmode.Send(Instance);
 225
 226                 std::deque<std::string> params;
 227                 params.push_back(Current->GetName());
 228                 params.push_back(":"+reason);
 229                 Utils->DoOneToAllButSender(Current->GetParent()->GetName(),"SQUIT",params,Current->GetName());
 230                 if (Current->GetParent() == Utils->TreeRoot)
 231                 {
 232                         this->Instance->SNO->WriteToSnoMask('l',"Server \002"+Current->GetName()+"\002 split: "+reason);
 233                 }
 234                 else
 235                 {
 236                         this->Instance->SNO->WriteToSnoMask('l',"Server \002"+Current->GetName()+"\002 split from server \002"+Current->GetParent()->GetName()+"\002 with reason: "+reason);
 237                 }
 238                 num_lost_servers = 0;
 239                 num_lost_users = 0;
 240                 std::string from = Current->GetParent()->GetName()+" "+Current->GetName();
 241                 SquitServer(from, Current);
 242                 Current->Tidy();
 243                 Current->GetParent()->DelChild(Current);
 244                 delete Current;
 245                 this->Instance->SNO->WriteToSnoMask('l',"Netsplit complete, lost \002%d\002 users on \002%d\002 servers.", num_lost_users, num_lost_servers);
 246         }
 247         else
 248                 Instance->Logs->Log("m_spanningtree",DEFAULT,"Squit from unknown server");
 249 }
 250
 251 /** This function is called when we receive data from a remote
 252  * server. We buffer the data in a std::string (it doesnt stay
 253  * there for long), reading using BufferedSocket::Read() which can
 254  * read up to 16 kilobytes in one operation.
 255  *
 256  * IF THIS FUNCTION RETURNS FALSE, THE CORE CLOSES AND DELETES
 257  * THE SOCKET OBJECT FOR US.
 258  */
 259 bool TreeSocket::OnDataReady()
 260 {
 261         const char* data = this->Read();
 262         /* Check that the data read is a valid pointer and it has some content */
 263         if (data && *data)
 264         {
 265                 this->in_buffer.append(data);
 266                 /* While there is at least one new line in the buffer,
 267                  * do something useful (we hope!) with it.
 268                  */
 269                 while (in_buffer.find("\n") != std::string::npos)
 270                 {
 271                         std::string ret = in_buffer.substr(0,in_buffer.find("\n")-1);
 272                         in_buffer = in_buffer.substr(in_buffer.find("\n")+1,in_buffer.length()-in_buffer.find("\n"));
 273                         /* Use rfind here not find, as theres more
 274                          * chance of the \r being near the end of the
 275                          * string, not the start.
 276                          */
 277                         if (ret.find("\r") != std::string::npos)
 278                                 ret = in_buffer.substr(0,in_buffer.find("\r")-1);
 279                         /* Process this one, abort if it
 280                          * didnt return true.
 281                          */
 282                         if (!this->ProcessLine(ret))
 283                         {
 284                                 return false;
 285                         }
 286                 }
 287                 return true;
 288         }
 289         /* EAGAIN returns an empty but non-NULL string, so this
 290          * evaluates to TRUE for EAGAIN but to FALSE for EOF.
 291          */
 292         return (data && !*data);
 293 }