gvpe/src/vpn_tcp.C

/*
    vpn_tcp.C -- handle the tcp part of the protocol.
    Copyright (C) 2003-2005 Marc Lehmann <gvpe@schmorp.de>
 
    This file is part of GVPE.

    GVPE 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; either version 2 of the License, or
    (at your option) any later version.
 
    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 gvpe; if not, write to the Free Software
    Foundation, Inc. 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
*/

#include "config.h"

#if ENABLE_TCP

// tcp processing is extremely ugly, since the vpe protocol is simply
// designed for unreliable datagram networks. tcp is implemented by
// multiplexing packets over tcp. errors are completely ignored, as we
// rely on the higher level protocol to time out and reconnect.

#include <cstring>

#include <sys/types.h>
#include <sys/socket.h>
#include <sys/wait.h>
#include <sys/uio.h>
#include <errno.h>
#include <time.h>
#include <unistd.h>
#include <fcntl.h>

#include <map>

#include "netcompat.h"

#include "vpn.h"

#if ENABLE_HTTP_PROXY
# include "conf.h"
#endif

struct tcp_connection;

struct lt_sockinfo
{
  bool operator()(const sockinfo *a, const sockinfo *b) const
  {
    return *a < *b;
  }
};

struct tcp_si_map : public map<const sockinfo *, tcp_connection *, lt_sockinfo> {
  void cleaner_cb (time_watcher &w); time_watcher cleaner;

  tcp_si_map ()
  : cleaner(this, &tcp_si_map::cleaner_cb)
  { }

} tcp_si;

struct tcp_connection : io_watcher {
  tstamp last_activity;
  const sockinfo si;
  vpn &v;
  bool active; // this connection has been actively established
  enum { ERROR, IDLE, CONNECTING, CONNECTING_PROXY, ESTABLISHED } state;

  vpn_packet *r_pkt;
  u32 r_len, r_ofs;

  vpn_packet *w_pkt;
  u32 w_len, w_ofs;

#if ENABLE_HTTP_PROXY
  char *proxy_req;
  int proxy_req_len;
#endif

  void tcpv4_ev (io_watcher &w, short revents);

  bool send_packet (vpn_packet *pkt, int tos);
  bool write_packet ();

  void error (); // abort conenction && cleanup

  operator tcp_si_map::value_type()
  {
    return tcp_si_map::value_type (&si, this);
  }

  tcp_connection (int fd_, const sockinfo &si_, vpn &v_);
  ~tcp_connection ();
};

void tcp_si_map::cleaner_cb (time_watcher &w)
{
  w.start (NOW + 600);

  tstamp to = NOW - ::conf.keepalive - 30 - 60;

  for (iterator i = begin (); i != end(); )
    if (i->second->last_activity >= to)
      ++i;
    else
      {
        erase (i);
        i = begin ();
      }
}

void
vpn::tcpv4_ev (io_watcher &w, short revents)
{
  if (revents & EVENT_READ)
    {
      struct sockaddr_in sa;
      socklen_t sa_len = sizeof (sa);
      int len;

      int fd = accept (w.fd, (sockaddr *)&sa, &sa_len);

      if (fd >= 0)
        {
          sockinfo si(sa, PROT_TCPv4);

          slog (L_DEBUG, _("%s: accepted tcp connection"), (const char *)si);//D

          fcntl (fd, F_SETFL, O_NONBLOCK);

          tcp_connection *i = new tcp_connection (fd, si, *this);
          tcp_si.insert (*i);
        }
    }
}

bool
vpn::send_tcpv4_packet (vpn_packet *pkt, const sockinfo &si, int tos)
{
  tcp_si_map::iterator info = tcp_si.find (&si);

  tcp_connection *i;

  if (info == tcp_si.end ())
    {
      i = new tcp_connection (-1, si, *this);
      tcp_si.insert (*i);
    }
  else
    i = info->second;

  return i->send_packet (pkt, tos);
}

bool
tcp_connection::write_packet ()
{
  ssize_t len;

  if (w_ofs < 2)
    {
      u16 plen = htons (w_pkt->len);

      iovec vec[2];
      //TODO: char* is the right type? hardly...
      vec[0].iov_base = (char *)((u8 *)&plen) + w_ofs;
      vec[0].iov_len = 2 - w_ofs;
      vec[1].iov_base = (char *)&((*w_pkt)[0]);
      vec[1].iov_len = w_len - 2;

      len = writev (fd, vec, 2);
    }
  else
    len = write (fd, &((*w_pkt)[w_ofs - 2]), w_len);

  if (len > 0)
    {
      w_ofs += len;
      w_len -= len;

      return w_len == 0;
    }
  else if (len < 0 && (errno == EAGAIN || errno == EINTR))
    return false;
  else
    {
      error ();
      return false;
    }
}

void
tcp_connection::tcpv4_ev (io_watcher &w, short revents)
{
  last_activity = NOW;

  if (revents & EVENT_WRITE)
    {
      if (state == CONNECTING)
        {
          state = ESTABLISHED;
          set (EVENT_READ);
#if ENABLE_HTTP_PROXY
          if (::conf.proxy_host && ::conf.proxy_port)
            {
              state = CONNECTING_PROXY;

              if (write (fd, proxy_req, proxy_req_len) == 0)
                {
                  error ();
                  return;
                }

              free (proxy_req); proxy_req = 0;
            }
#endif
        }
      else if (state == ESTABLISHED)
        {
          if (w_pkt)
            {
              if (write_packet ())
                {
                  delete w_pkt; w_pkt = 0;

                  set (EVENT_READ);
                }
            }
          else
            set (EVENT_READ);
        }
      else
        set (EVENT_READ);
    }

  if (revents & EVENT_READ)
    {
      if (state == ESTABLISHED)
        for (;;)
          {
            if (!r_pkt)
              {
                r_pkt = new vpn_packet;
                r_ofs = 0;
                r_len = 2; // header
              }

            ssize_t len = read (fd, &((*r_pkt)[r_ofs < 2 ? r_ofs : r_ofs - 2]), r_len);

            if (len > 0)
              {
                r_len -= len;
                r_ofs += len;

                if (r_len == 0)
                  {
                    if (r_ofs == 2)
                      {
                        r_len = ntohs (*(u16 *)&((*r_pkt)[0]));
                        r_pkt->len = r_len;

                        if (r_len > 0 && r_len < MAXSIZE)
                          continue;
                      }
                    else
                      {
                        v.recv_vpn_packet (r_pkt, si);
                        delete r_pkt;
                        r_pkt = 0;

                        continue;
                      }
                  }
                else
                  break;
              }
            else if (len < 0 && (errno == EINTR || errno == EAGAIN))
              break;

            // len == 0 <-> EOF
            error ();
            break;
          }
#if ENABLE_HTTP_PROXY
      else if (state == CONNECTING_PROXY)
        {
          fcntl (fd, F_SETFL, 0);
          char r[1024];
          int i;
          bool emptyline = false;

          // we do a blocking read of the response, to hell with it
          for (i = 0; i < 1023; i++)
            {
              int l = read (fd, &r[i], 1);

              if (l <= 0)
                {
                  error ();
                  return;
                }

              if (r[i] == '\012')
                {
                  if (emptyline)
                    break;
                  else
                    emptyline = true;
                }
              else if (r[i] != '\015')
                emptyline = false;
            }

          fcntl (fd, F_SETFL, O_NONBLOCK);

          if (i < 12)
            {
              slog (L_ERR, _("(%s): unable to do proxy-forwarding, short response"),
                    (const char *)si);
              error ();
            }
          else if (r[0] != 'H' || r[1] != 'T' || r[2] != 'T' || r[3] != 'P' || r[4] != '/'
                   || r[5] != '1' // http-major
                   || r[9] != '2') // response
            {
              slog (L_ERR, _("(%s): malformed or unexpected proxy response (%.12s)"),
                    (const char *)si, r);
              error ();
            }
          else
            state = ESTABLISHED;
        }
#endif
    }
}

bool
tcp_connection::send_packet (vpn_packet *pkt, int tos)
{
  last_activity = NOW;

  if (state == IDLE)
    {
      // woaw, the first lost packet ;)
      fd = socket (PF_INET, SOCK_STREAM, IPPROTO_TCP);

      if (fd >= 0)
        {
          const sockinfo *csi = &si;

#if ENABLE_HTTP_PROXY
          sockinfo psi;

          if (::conf.proxy_host && ::conf.proxy_port)
            {
              psi.set (::conf.proxy_host, ::conf.proxy_port, PROT_TCPv4);

              if (psi.valid ())
                {
                  csi = &psi;

                  proxy_req_len = asprintf (&proxy_req,
                                            "CONNECT %s:%d HTTP/1.0\015\012"
                                            "%s%s%s" // optional proxy-auth
                                            "\015\012",
                                            si.ntoa (),
                                            ntohs (si.port),
                                            ::conf.proxy_auth ? "Proxy-Authorization: Basic " : "",
                                            ::conf.proxy_auth ? ::conf.proxy_auth             : "",
                                            ::conf.proxy_auth ? "\015\012"                    : "");

                }
              else
                slog (L_ERR, _("unable to resolve http proxy hostname '%s', trying direct"),
                      ::conf.proxy_host);
            }
#endif
          
          fcntl (fd, F_SETFL, O_NONBLOCK);

          if (connect (fd, csi->sav4 (), csi->salenv4 ()) >= 0
              || errno == EINPROGRESS)
            {
              state = CONNECTING;
              start (fd, EVENT_WRITE);
            }
          else
            close (fd);
        }
    }
  else if (state == ESTABLISHED)
    {
      // drop packet if the tcp write buffer is full. this *is* the
      // right thing to do, not using tcp *is* the right thing to do.
      if (!w_pkt)
        {
          // how this maps to the underlying tcp packets we don't know
          // and we don't care. at least we tried ;)
#if defined(SOL_IP) && defined(IP_TOS)
          setsockopt (fd, SOL_IP, IP_TOS, &tos, sizeof tos);
#endif

          w_pkt = pkt;
          w_ofs = 0;
          w_len = pkt->len + 2; // length + size header

          if (write_packet ())
            w_pkt = 0;
          else
            {
              w_pkt = new vpn_packet;
              w_pkt->set (*pkt);

              set (EVENT_READ | EVENT_WRITE);
            }
        }
    }

  return state != ERROR;
}

void tcp_connection::error ()
{
  if (fd >= 0)
    {
      close (fd);
      fd = -1;
    }

  delete r_pkt; r_pkt = 0;
  delete w_pkt; w_pkt = 0;
#if ENABLE_HTTP_PROXY
  free (proxy_req); proxy_req = 0;
#endif

  stop ();
  state = active ? IDLE : ERROR;
}

tcp_connection::tcp_connection (int fd_, const sockinfo &si_, vpn &v_)
: v(v_), si(si_), io_watcher(this, &tcp_connection::tcpv4_ev)
{
  if (!tcp_si.cleaner.active)
    tcp_si.cleaner.start (0);

  last_activity = NOW;
  r_pkt = 0;
  w_pkt = 0;
  fd = fd_;
#if ENABLE_HTTP_PROXY
  proxy_req = 0;
#endif

  if (fd < 0)
    {
      active = true;
      state = IDLE;
    }
  else
    {
      active = false;
      state = ESTABLISHED;
      start (fd, EVENT_READ);
    }
}

tcp_connection::~tcp_connection ()
{
  error ();
}

#endif

Revision:	1.14
Committed:	Tue Apr 26 00:55:56 2005 UTC (19 years, 1 month ago) by pcg
Content type:	text/plain
Branch:	MAIN
Changes since 1.13:	+1 -1 lines
Log Message:	* empty log message *
#	User	Rev	Content
1	pcg	1.1	/*
2			vpn_tcp.C -- handle the tcp part of the protocol.
3	pcg	1.12	Copyright (C) 2003-2005 Marc Lehmann <gvpe@schmorp.de>
4	pcg	1.1
5	pcg	1.12	This file is part of GVPE.
6
7			GVPE is free software; you can redistribute it and/or modify
8	pcg	1.1	it under the terms of the GNU General Public License as published by
9			the Free Software Foundation; either version 2 of the License, or
10			(at your option) any later version.
11
12			This program is distributed in the hope that it will be useful,
13			but WITHOUT ANY WARRANTY; without even the implied warranty of
14			MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15			GNU General Public License for more details.
16
17			You should have received a copy of the GNU General Public License
18	pcg	1.12	along with gvpe; if not, write to the Free Software
19	pcg	1.14	Foundation, Inc. 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20	pcg	1.1	*/
21
22			#include "config.h"
23
24			#if ENABLE_TCP
25
26			// tcp processing is extremely ugly, since the vpe protocol is simply
27			// designed for unreliable datagram networks. tcp is implemented by
28			// multiplexing packets over tcp. errors are completely ignored, as we
29			// rely on the higher level protocol to time out and reconnect.
30
31			#include <cstring>
32
33			#include <sys/types.h>
34			#include <sys/socket.h>
35			#include <sys/wait.h>
36			#include <sys/uio.h>
37			#include <errno.h>
38			#include <time.h>
39			#include <unistd.h>
40	pcg	1.9	#include <fcntl.h>
41	pcg	1.1
42			#include <map>
43	pcg	1.8
44			#include "netcompat.h"
45	pcg	1.1
46			#include "vpn.h"
47
48	pcg	1.4	#if ENABLE_HTTP_PROXY
49			# include "conf.h"
50			#endif
51
52	pcg	1.1	struct tcp_connection;
53
54			struct lt_sockinfo
55			{
56			bool operator()(const sockinfo a, const sockinfo b) const
57			{
58			return a < b;
59			}
60			};
61
62			struct tcp_si_map : public map<const sockinfo , tcp_connection , lt_sockinfo> {
63			void cleaner_cb (time_watcher &w); time_watcher cleaner;
64
65			tcp_si_map ()
66	pcg	1.13	: cleaner(this, &tcp_si_map::cleaner_cb)
67			{ }
68
69	pcg	1.1	} tcp_si;
70
71			struct tcp_connection : io_watcher {
72			tstamp last_activity;
73			const sockinfo si;
74			vpn &v;
75			bool active; // this connection has been actively established
76	pcg	1.4	enum { ERROR, IDLE, CONNECTING, CONNECTING_PROXY, ESTABLISHED } state;
77	pcg	1.1
78			vpn_packet *r_pkt;
79			u32 r_len, r_ofs;
80
81	pcg	1.3	vpn_packet *w_pkt;
82			u32 w_len, w_ofs;
83
84	pcg	1.4	#if ENABLE_HTTP_PROXY
85			char *proxy_req;
86			int proxy_req_len;
87			#endif
88
89	pcg	1.1	void tcpv4_ev (io_watcher &w, short revents);
90
91	pcg	1.2	bool send_packet (vpn_packet *pkt, int tos);
92	pcg	1.3	bool write_packet ();
93	pcg	1.1
94			void error (); // abort conenction && cleanup
95
96			operator tcp_si_map::value_type()
97	pcg	1.13	{
98			return tcp_si_map::value_type (&si, this);
99			}
100	pcg	1.1
101			tcp_connection (int fd_, const sockinfo &si_, vpn &v_);
102			~tcp_connection ();
103			};
104
105			void tcp_si_map::cleaner_cb (time_watcher &w)
106			{
107	pcg	1.11	w.start (NOW + 600);
108
109	pcg	1.1	tstamp to = NOW - ::conf.keepalive - 30 - 60;
110
111			for (iterator i = begin (); i != end(); )
112			if (i->second->last_activity >= to)
113			++i;
114			else
115			{
116			erase (i);
117			i = begin ();
118			}
119			}
120
121			void
122			vpn::tcpv4_ev (io_watcher &w, short revents)
123			{
124	pcg	1.11	if (revents & EVENT_READ)
125	pcg	1.1	{
126			struct sockaddr_in sa;
127			socklen_t sa_len = sizeof (sa);
128			int len;
129
130			int fd = accept (w.fd, (sockaddr *)&sa, &sa_len);
131
132			if (fd >= 0)
133			{
134			sockinfo si(sa, PROT_TCPv4);
135
136			slog (L_DEBUG, _("%s: accepted tcp connection"), (const char *)si);//D
137
138			fcntl (fd, F_SETFL, O_NONBLOCK);
139
140			tcp_connection i = new tcp_connection (fd, si, this);
141			tcp_si.insert (*i);
142			}
143			}
144			}
145
146	pcg	1.2	bool
147	pcg	1.1	vpn::send_tcpv4_packet (vpn_packet *pkt, const sockinfo &si, int tos)
148			{
149			tcp_si_map::iterator info = tcp_si.find (&si);
150
151			tcp_connection *i;
152
153			if (info == tcp_si.end ())
154			{
155			i = new tcp_connection (-1, si, *this);
156			tcp_si.insert (*i);
157			}
158			else
159			i = info->second;
160
161	pcg	1.2	return i->send_packet (pkt, tos);
162	pcg	1.1	}
163
164	pcg	1.3	bool
165			tcp_connection::write_packet ()
166			{
167			ssize_t len;
168
169			if (w_ofs < 2)
170			{
171			u16 plen = htons (w_pkt->len);
172
173			iovec vec[2];
174	pcg	1.7	//TODO: char* is the right type? hardly...
175			vec[0].iov_base = (char )((u8 )&plen) + w_ofs;
176	pcg	1.3	vec[0].iov_len = 2 - w_ofs;
177	pcg	1.7	vec[1].iov_base = (char )&((w_pkt)[0]);
178	pcg	1.3	vec[1].iov_len = w_len - 2;
179
180			len = writev (fd, vec, 2);
181			}
182			else
183			len = write (fd, &((*w_pkt)[w_ofs - 2]), w_len);
184
185			if (len > 0)
186			{
187			w_ofs += len;
188			w_len -= len;
189
190			return w_len == 0;
191			}
192			else if (len < 0 && (errno == EAGAIN \|\| errno == EINTR))
193			return false;
194			else
195			{
196			error ();
197			return false;
198			}
199			}
200
201	pcg	1.1	void
202			tcp_connection::tcpv4_ev (io_watcher &w, short revents)
203			{
204			last_activity = NOW;
205
206	pcg	1.11	if (revents & EVENT_WRITE)
207	pcg	1.3	{
208			if (state == CONNECTING)
209			{
210			state = ESTABLISHED;
211	pcg	1.11	set (EVENT_READ);
212	pcg	1.4	#if ENABLE_HTTP_PROXY
213			if (::conf.proxy_host && ::conf.proxy_port)
214			{
215			state = CONNECTING_PROXY;
216	pcg	1.11
217			if (write (fd, proxy_req, proxy_req_len) == 0)
218			{
219			error ();
220			return;
221			}
222
223	pcg	1.4	free (proxy_req); proxy_req = 0;
224			}
225			#endif
226	pcg	1.3	}
227			else if (state == ESTABLISHED)
228			{
229			if (w_pkt)
230			{
231			if (write_packet ())
232			{
233			delete w_pkt; w_pkt = 0;
234
235	pcg	1.11	set (EVENT_READ);
236	pcg	1.3	}
237			}
238			else
239	pcg	1.11	set (EVENT_READ);
240	pcg	1.3	}
241			else
242	pcg	1.11	set (EVENT_READ);
243	pcg	1.3	}
244
245	pcg	1.11	if (revents & EVENT_READ)
246	pcg	1.1	{
247	pcg	1.4	if (state == ESTABLISHED)
248			for (;;)
249			{
250			if (!r_pkt)
251			{
252			r_pkt = new vpn_packet;
253			r_ofs = 0;
254			r_len = 2; // header
255			}
256
257			ssize_t len = read (fd, &((*r_pkt)[r_ofs < 2 ? r_ofs : r_ofs - 2]), r_len);
258
259			if (len > 0)
260			{
261			r_len -= len;
262			r_ofs += len;
263
264			if (r_len == 0)
265			{
266			if (r_ofs == 2)
267			{
268			r_len = ntohs ((u16 )&((*r_pkt)[0]));
269			r_pkt->len = r_len;
270
271			if (r_len > 0 && r_len < MAXSIZE)
272			continue;
273			}
274			else
275			{
276			v.recv_vpn_packet (r_pkt, si);
277			delete r_pkt;
278			r_pkt = 0;
279
280			continue;
281			}
282			}
283			else
284			break;
285			}
286			else if (len < 0 && (errno == EINTR \|\| errno == EAGAIN))
287			break;
288
289	pcg	1.11	// len == 0 <-> EOF
290	pcg	1.4	error ();
291			break;
292			}
293			#if ENABLE_HTTP_PROXY
294			else if (state == CONNECTING_PROXY)
295	pcg	1.1	{
296	pcg	1.4	fcntl (fd, F_SETFL, 0);
297			char r[1024];
298			int i;
299			bool emptyline = false;
300	pcg	1.1
301	pcg	1.4	// we do a blocking read of the response, to hell with it
302			for (i = 0; i < 1023; i++)
303	pcg	1.1	{
304	pcg	1.4	int l = read (fd, &r[i], 1);
305	pcg	1.1
306	pcg	1.4	if (l <= 0)
307	pcg	1.1	{
308	pcg	1.4	error ();
309			return;
310			}
311	pcg	1.1
312	pcg	1.4	if (r[i] == '\012')
313			{
314			if (emptyline)
315			break;
316	pcg	1.1	else
317	pcg	1.4	emptyline = true;
318	pcg	1.1	}
319	pcg	1.4	else if (r[i] != '\015')
320			emptyline = false;
321	pcg	1.1	}
322
323	pcg	1.4	fcntl (fd, F_SETFL, O_NONBLOCK);
324
325			if (i < 12)
326			{
327	pcg	1.6	slog (L_ERR, _("(%s): unable to do proxy-forwarding, short response"),
328	pcg	1.5	(const char *)si);
329	pcg	1.4	error ();
330			}
331			else if (r[0] != 'H' \|\| r[1] != 'T' \|\| r[2] != 'T' \|\| r[3] != 'P' \|\| r[4] != '/'
332			\|\| r[5] != '1' // http-major
333			\|\| r[9] != '2') // response
334			{
335	pcg	1.6	slog (L_ERR, _("(%s): malformed or unexpected proxy response (%.12s)"),
336	pcg	1.5	(const char *)si, r);
337	pcg	1.4	error ();
338			}
339			else
340			state = ESTABLISHED;
341	pcg	1.1	}
342	pcg	1.4	#endif
343	pcg	1.1	}
344			}
345
346	pcg	1.2	bool
347	pcg	1.1	tcp_connection::send_packet (vpn_packet *pkt, int tos)
348			{
349			last_activity = NOW;
350
351			if (state == IDLE)
352			{
353			// woaw, the first lost packet ;)
354			fd = socket (PF_INET, SOCK_STREAM, IPPROTO_TCP);
355
356			if (fd >= 0)
357			{
358	pcg	1.4	const sockinfo *csi = &si;
359
360			#if ENABLE_HTTP_PROXY
361			sockinfo psi;
362
363			if (::conf.proxy_host && ::conf.proxy_port)
364			{
365			psi.set (::conf.proxy_host, ::conf.proxy_port, PROT_TCPv4);
366
367			if (psi.valid ())
368			{
369			csi = ψ
370
371			proxy_req_len = asprintf (&proxy_req,
372			"CONNECT %s:%d HTTP/1.0\015\012"
373			"%s%s%s" // optional proxy-auth
374			"\015\012",
375			si.ntoa (),
376			ntohs (si.port),
377			::conf.proxy_auth ? "Proxy-Authorization: Basic " : "",
378			::conf.proxy_auth ? ::conf.proxy_auth : "",
379			::conf.proxy_auth ? "\015\012" : "");
380
381			}
382			else
383			slog (L_ERR, _("unable to resolve http proxy hostname '%s', trying direct"),
384			::conf.proxy_host);
385			}
386			#endif
387
388	pcg	1.1	fcntl (fd, F_SETFL, O_NONBLOCK);
389	pcg	1.4
390			if (connect (fd, csi->sav4 (), csi->salenv4 ()) >= 0
391	pcg	1.1	\|\| errno == EINPROGRESS)
392			{
393			state = CONNECTING;
394	pcg	1.11	start (fd, EVENT_WRITE);
395	pcg	1.1	}
396			else
397			close (fd);
398			}
399			}
400			else if (state == ESTABLISHED)
401			{
402	pcg	1.3	// drop packet if the tcp write buffer is full. this is the
403			// right thing to do, not using tcp is the right thing to do.
404			if (!w_pkt)
405			{
406			// how this maps to the underlying tcp packets we don't know
407			// and we don't care. at least we tried ;)
408	pcg	1.7	#if defined(SOL_IP) && defined(IP_TOS)
409	pcg	1.3	setsockopt (fd, SOL_IP, IP_TOS, &tos, sizeof tos);
410	pcg	1.7	#endif
411	pcg	1.3
412			w_pkt = pkt;
413			w_ofs = 0;
414			w_len = pkt->len + 2; // length + size header
415
416			if (write_packet ())
417			w_pkt = 0;
418			else
419			{
420			w_pkt = new vpn_packet;
421			w_pkt->set (*pkt);
422	pcg	1.1
423	pcg	1.11	set (EVENT_READ \| EVENT_WRITE);
424	pcg	1.3	}
425			}
426	pcg	1.1	}
427	pcg	1.2
428			return state != ERROR;
429	pcg	1.1	}
430
431	pcg	1.4	void tcp_connection::error ()
432			{
433			if (fd >= 0)
434			{
435			close (fd);
436			fd = -1;
437			}
438
439			delete r_pkt; r_pkt = 0;
440			delete w_pkt; w_pkt = 0;
441			#if ENABLE_HTTP_PROXY
442			free (proxy_req); proxy_req = 0;
443			#endif
444
445			stop ();
446			state = active ? IDLE : ERROR;
447			}
448
449	pcg	1.1	tcp_connection::tcp_connection (int fd_, const sockinfo &si_, vpn &v_)
450			: v(v_), si(si_), io_watcher(this, &tcp_connection::tcpv4_ev)
451			{
452	pcg	1.13	if (!tcp_si.cleaner.active)
453			tcp_si.cleaner.start (0);
454
455	pcg	1.1	last_activity = NOW;
456			r_pkt = 0;
457	pcg	1.3	w_pkt = 0;
458	pcg	1.1	fd = fd_;
459	pcg	1.4	#if ENABLE_HTTP_PROXY
460			proxy_req = 0;
461			#endif
462	pcg	1.1
463			if (fd < 0)
464			{
465			active = true;
466			state = IDLE;
467			}
468			else
469			{
470			active = false;
471			state = ESTABLISHED;
472	pcg	1.11	start (fd, EVENT_READ);
473	pcg	1.1	}
474			}
475
476			tcp_connection::~tcp_connection ()
477			{
478			error ();
479			}
480
481			#endif
482