src/listensocket.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  InspIRCd: (C) 2002-2009 InspIRCd Development Team
   6  * See: http://wiki.inspircd.org/Credits
   7  *
   8  * This program is free but copyrighted software; see
   9  *            the file COPYING for details.
  10  *
  11  * ---------------------------------------------------
  12  */
  13
  14 /* $Core */
  15
  16 #include "inspircd.h"
  17 #include "socket.h"
  18 #include "socketengine.h"
  19
  20 ListenSocket::ListenSocket(ConfigTag* tag, const std::string& addr, int port)
  21         : bind_tag(tag)
  22 {
  23         irc::sockets::sockaddrs bind_to;
  24
  25         // canonicalize address if it is defined
  26         if (!irc::sockets::aptosa(addr, port, bind_to))
  27         {
  28                 fd = -1;
  29                 return;
  30         }
  31         irc::sockets::satoap(bind_to, bind_addr, bind_port);
  32         bind_desc = irc::sockets::satouser(bind_to);
  33
  34         fd = irc::sockets::OpenTCPSocket(bind_addr);
  35
  36         if (this->fd > -1)
  37         {
  38                 int rv = ServerInstance->SE->Bind(this->fd, &bind_to.sa, sizeof(bind_to));
  39                 if (rv >= 0)
  40                         rv = ServerInstance->SE->Listen(this->fd, ServerInstance->Config->MaxConn);
  41
  42                 if (rv < 0)
  43                 {
  44                         ServerInstance->SE->Shutdown(this, 2);
  45                         ServerInstance->SE->Close(this);
  46                         this->fd = -1;
  47                 }
  48                 else
  49                 {
  50                         ServerInstance->SE->NonBlocking(this->fd);
  51                         ServerInstance->SE->AddFd(this, FD_WANT_POLL_READ | FD_WANT_NO_WRITE);
  52                 }
  53         }
  54 }
  55
  56 ListenSocket::~ListenSocket()
  57 {
  58         if (this->GetFd() > -1)
  59         {
  60                 ServerInstance->SE->DelFd(this);
  61                 ServerInstance->Logs->Log("SOCKET", DEBUG,"Shut down listener on fd %d", this->fd);
  62                 if (ServerInstance->SE->Shutdown(this, 2) || ServerInstance->SE->Close(this))
  63                         ServerInstance->Logs->Log("SOCKET", DEBUG,"Failed to cancel listener: %s", strerror(errno));
  64                 this->fd = -1;
  65         }
  66 }
  67
  68 /* Just seperated into another func for tidiness really.. */
  69 void ListenSocket::AcceptInternal()
  70 {
  71         irc::sockets::sockaddrs client;
  72         irc::sockets::sockaddrs server;
  73
  74         ServerInstance->Logs->Log("SOCKET",DEBUG,"HandleEvent for Listensoket");
  75         int incomingSockfd;
  76
  77         socklen_t length = sizeof(client);
  78         incomingSockfd = ServerInstance->SE->Accept(this, &client.sa, &length);
  79
  80         if (incomingSockfd < 0)
  81         {
  82                 ServerInstance->SE->Shutdown(incomingSockfd, 2);
  83                 ServerInstance->SE->Close(incomingSockfd);
  84                 ServerInstance->stats->statsRefused++;
  85                 return;
  86         }
  87
  88         socklen_t sz = sizeof(server);
  89         if (getsockname(incomingSockfd, &server.sa, &sz))
  90                 ServerInstance->Logs->Log("SOCKET", DEBUG, "Can't get peername: %s", strerror(errno));
  91
  92         /*
  93          * XXX -
  94          * this is done as a safety check to keep the file descriptors within range of fd_ref_table.
  95          * its a pretty big but for the moment valid assumption:
  96          * file descriptors are handed out starting at 0, and are recycled as theyre freed.
  97          * therefore if there is ever an fd over 65535, 65536 clients must be connected to the
  98          * irc server at once (or the irc server otherwise initiating this many connections, files etc)
  99          * which for the time being is a physical impossibility (even the largest networks dont have more
 100          * than about 10,000 users on ONE server!)
 101          */
 102         if (incomingSockfd >= ServerInstance->SE->GetMaxFds())
 103         {
 104                 ServerInstance->Logs->Log("SOCKET", DEBUG, "Server is full");
 105                 ServerInstance->SE->Shutdown(incomingSockfd, 2);
 106                 ServerInstance->SE->Close(incomingSockfd);
 107                 ServerInstance->stats->statsRefused++;
 108                 return;
 109         }
 110
 111         if (client.sa.sa_family == AF_INET6)
 112         {
 113                 /*
 114                  * This case is the be all and end all patch to catch and nuke 4in6
 115                  * instead of special-casing shit all over the place and wreaking merry
 116                  * havoc with crap, instead, we just recreate sockaddr and strip ::ffff: prefix
 117                  * if it's a 4in6 IP.
 118                  *
 119                  * This is, of course, much improved over the older way of handling this
 120                  * (pretend it doesn't exist + hack around it -- yes, both were done!)
 121                  *
 122                  * Big, big thanks to danieldg for his work on this.
 123                  * -- w00t
 124                  */
 125                 static const unsigned char prefix4in6[12] = { 0,0,0,0, 0,0,0,0, 0,0,0xFF,0xFF };
 126                 if (!memcmp(prefix4in6, &client.in6.sin6_addr, 12))
 127                 {
 128                         // recreate as a sockaddr_in using the IPv4 IP
 129                         uint16_t sport = client.in6.sin6_port;
 130                         uint32_t addr = *reinterpret_cast<uint32_t*>(client.in6.sin6_addr.s6_addr + 12);
 131                         client.in4.sin_family = AF_INET;
 132                         client.in4.sin_port = sport;
 133                         client.in4.sin_addr.s_addr = addr;
 134
 135                         sport = server.in6.sin6_port;
 136                         addr = *reinterpret_cast<uint32_t*>(server.in6.sin6_addr.s6_addr + 12);
 137                         server.in4.sin_family = AF_INET;
 138                         server.in4.sin_port = sport;
 139                         server.in4.sin_addr.s_addr = addr;
 140                 }
 141         }
 142
 143         ServerInstance->SE->NonBlocking(incomingSockfd);
 144         ServerInstance->stats->statsAccept++;
 145
 146         ModResult res;
 147         FIRST_MOD_RESULT(OnAcceptConnection, res, (incomingSockfd, this, &client, &server));
 148         if (res == MOD_RES_PASSTHRU)
 149         {
 150                 std::string type = bind_tag->getString("type", "clients");
 151                 if (type == "clients")
 152                 {
 153                         ServerInstance->Users->AddUser(incomingSockfd, this, &client, &server);
 154                         res = MOD_RES_ALLOW;
 155                 }
 156         }
 157         if (res != MOD_RES_ALLOW)
 158                 ServerInstance->SE->Close(incomingSockfd);
 159 }
 160
 161 void ListenSocket::HandleEvent(EventType e, int err)
 162 {
 163         switch (e)
 164         {
 165                 case EVENT_ERROR:
 166                         ServerInstance->Logs->Log("SOCKET",DEFAULT,"ListenSocket::HandleEvent() received a socket engine error event! well shit! '%s'", strerror(err));
 167                         break;
 168                 case EVENT_WRITE:
 169                         ServerInstance->Logs->Log("SOCKET",DEBUG,"*** BUG *** ListenSocket::HandleEvent() got a WRITE event!!!");
 170                         break;
 171                 case EVENT_READ:
 172                         this->AcceptInternal();
 173                         break;
 174         }
 175 }