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/*
* InspIRCd -- Internet Relay Chat Daemon
*
* Copyright (C) 2009-2010 Daniel De Graaf <danieldg@inspircd.org>
* Copyright (C) 2008 Robin Burchell <robin+git@viroteck.net>
*
* This file is part of InspIRCd. InspIRCd is free software: you can
* redistribute it and/or modify it under the terms of the GNU General Public
* License as published by the Free Software Foundation, version 2.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
* FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
* details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "inspircd.h"
#include "iohook.h"
#ifndef _WIN32
#include <netinet/tcp.h>
#endif
ListenSocket::ListenSocket(ConfigTag* tag, const irc::sockets::sockaddrs& bind_to)
: bind_tag(tag)
, bind_sa(bind_to)
{
// Are we creating a UNIX socket?
if (bind_to.family() == AF_UNIX)
{
// Is 'replace' enabled?
const bool replace = tag->getBool("replace");
if (replace && irc::sockets::isunix(bind_to.str()))
unlink(bind_to.str().c_str());
}
fd = socket(bind_to.family(), SOCK_STREAM, 0);
if (this->fd == -1)
return;
#ifdef IPV6_V6ONLY
/* This OS supports IPv6 sockets that can also listen for IPv4
* connections. If our address is "*" or empty, enable both v4 and v6 to
* allow for simpler configuration on dual-stack hosts. Otherwise, if it
* is "::" or an IPv6 address, disable support so that an IPv4 bind will
* work on the port (by us or another application).
*/
if (bind_to.family() == AF_INET6)
{
std::string addr = tag->getString("address");
/* This must be >= sizeof(DWORD) on Windows */
const int enable = (addr.empty() || addr == "*") ? 0 : 1;
/* This must be before bind() */
setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, reinterpret_cast<const char *>(&enable), sizeof(enable));
// errors ignored intentionally
}
#endif
if (tag->getBool("free"))
{
socklen_t enable = 1;
#if defined IP_FREEBIND // Linux 2.4+
setsockopt(fd, SOL_IP, IP_FREEBIND, &enable, sizeof(enable));
#elif defined IP_BINDANY // FreeBSD
setsockopt(fd, IPPROTO_IP, IP_BINDANY, &enable, sizeof(enable));
#elif defined SO_BINDANY // NetBSD/OpenBSD
setsockopt(fd, SOL_SOCKET, SO_BINDANY, &enable, sizeof(enable));
#else
(void)enable;
#endif
}
if (bind_to.family() == AF_UNIX)
{
const std::string permissionstr = tag->getString("permissions");
unsigned int permissions = strtoul(permissionstr.c_str(), NULL, 8);
if (permissions && permissions <= 07777)
chmod(bind_to.str().c_str(), permissions);
}
SocketEngine::SetReuse(fd);
int rv = SocketEngine::Bind(this->fd, bind_to);
if (rv >= 0)
rv = SocketEngine::Listen(this->fd, ServerInstance->Config->MaxConn);
// Default defer to on for TLS listeners because in TLS the client always speaks first
int timeout = tag->getDuration("defer", (tag->getString("ssl").empty() ? 0 : 3));
if (timeout && !rv)
{
#if defined TCP_DEFER_ACCEPT
setsockopt(fd, IPPROTO_TCP, TCP_DEFER_ACCEPT, &timeout, sizeof(timeout));
#elif defined SO_ACCEPTFILTER
struct accept_filter_arg afa;
memset(&afa, 0, sizeof(afa));
strcpy(afa.af_name, "dataready");
setsockopt(fd, SOL_SOCKET, SO_ACCEPTFILTER, &afa, sizeof(afa));
#endif
}
if (rv < 0)
{
int errstore = errno;
SocketEngine::Shutdown(this, 2);
SocketEngine::Close(this->GetFd());
this->fd = -1;
errno = errstore;
}
else
{
SocketEngine::NonBlocking(this->fd);
SocketEngine::AddFd(this, FD_WANT_POLL_READ | FD_WANT_NO_WRITE);
this->ResetIOHookProvider();
}
}
ListenSocket::~ListenSocket()
{
if (this->GetFd() > -1)
{
ServerInstance->Logs->Log("SOCKET", LOG_DEBUG, "Shut down listener on fd %d", this->fd);
SocketEngine::Shutdown(this, 2);
if (SocketEngine::Close(this) != 0)
ServerInstance->Logs->Log("SOCKET", LOG_DEBUG, "Failed to cancel listener: %s", strerror(errno));
if (bind_sa.family() == AF_UNIX && unlink(bind_sa.un.sun_path))
ServerInstance->Logs->Log("SOCKET", LOG_DEBUG, "Failed to unlink UNIX socket: %s", strerror(errno));
}
}
void ListenSocket::OnEventHandlerRead()
{
irc::sockets::sockaddrs client;
irc::sockets::sockaddrs server(bind_sa);
socklen_t length = sizeof(client);
int incomingSockfd = SocketEngine::Accept(this, &client.sa, &length);
ServerInstance->Logs->Log("SOCKET", LOG_DEBUG, "Accepting connection on socket %s fd %d", bind_sa.str().c_str(), incomingSockfd);
if (incomingSockfd < 0)
{
ServerInstance->stats.Refused++;
return;
}
socklen_t sz = sizeof(server);
if (getsockname(incomingSockfd, &server.sa, &sz))
{
ServerInstance->Logs->Log("SOCKET", LOG_DEBUG, "Can't get peername: %s", strerror(errno));
}
if (client.family() == AF_INET6)
{
/*
* This case is the be all and end all patch to catch and nuke 4in6
* instead of special-casing shit all over the place and wreaking merry
* havoc with crap, instead, we just recreate sockaddr and strip ::ffff: prefix
* if it's a 4in6 IP.
*
* This is, of course, much improved over the older way of handling this
* (pretend it doesn't exist + hack around it -- yes, both were done!)
*
* Big, big thanks to danieldg for his work on this.
* -- w00t
*/
static const unsigned char prefix4in6[12] = { 0,0,0,0, 0,0,0,0, 0,0,0xFF,0xFF };
if (!memcmp(prefix4in6, &client.in6.sin6_addr, 12))
{
// recreate as a sockaddr_in using the IPv4 IP
uint16_t sport = client.in6.sin6_port;
client.in4.sin_family = AF_INET;
client.in4.sin_port = sport;
memcpy(&client.in4.sin_addr.s_addr, client.in6.sin6_addr.s6_addr + 12, sizeof(uint32_t));
sport = server.in6.sin6_port;
server.in4.sin_family = AF_INET;
server.in4.sin_port = sport;
memcpy(&server.in4.sin_addr.s_addr, server.in6.sin6_addr.s6_addr + 12, sizeof(uint32_t));
}
}
else if (client.family() == AF_UNIX)
{
// Clients connecting via UNIX sockets don't have paths so give them
// the server path as defined in RFC 1459 section 8.1.1.
//
// strcpy is safe here because sizeof(sockaddr_un.sun_path) is equal on both.
strcpy(client.un.sun_path, server.un.sun_path);
}
SocketEngine::NonBlocking(incomingSockfd);
ModResult res;
FIRST_MOD_RESULT(OnAcceptConnection, res, (incomingSockfd, this, &client, &server));
if (res == MOD_RES_PASSTHRU)
{
std::string type = bind_tag->getString("type", "clients");
if (stdalgo::string::equalsci(type, "clients"))
{
ServerInstance->Users->AddUser(incomingSockfd, this, &client, &server);
res = MOD_RES_ALLOW;
}
}
if (res == MOD_RES_ALLOW)
{
ServerInstance->stats.Accept++;
}
else
{
ServerInstance->stats.Refused++;
ServerInstance->Logs->Log("SOCKET", LOG_DEFAULT, "Refusing connection on %s - %s",
bind_sa.str().c_str(), res == MOD_RES_DENY ? "Connection refused by module" : "Module for this port not found");
SocketEngine::Close(incomingSockfd);
}
}
void ListenSocket::ResetIOHookProvider()
{
iohookprovs[0].SetProvider(bind_tag->getString("hook"));
// Check that all non-last hooks support being in the middle
for (IOHookProvList::iterator i = iohookprovs.begin(); i != iohookprovs.end()-1; ++i)
{
IOHookProvRef& curr = *i;
// Ignore if cannot be in the middle
if ((curr) && (!curr->IsMiddle()))
curr.SetProvider(std::string());
}
std::string provname = bind_tag->getString("ssl");
if (!provname.empty())
provname.insert(0, "ssl/");
// SSL should be the last
iohookprovs.back().SetProvider(provname);
}
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