aboutsummaryrefslogtreecommitdiff
path: root/src/lib/connection_cleanup.c
blob: 8883213bef9986c944d883dd440c136ca236006a (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
/*
  This file is part of libmicrohttpd
  Copyright (C) 2007-2018 Daniel Pittman and Christian Grothoff

  This library is free software; you can redistribute it and/or
  modify it under the terms of the GNU Lesser General Public
  License as published by the Free Software Foundation; either
  version 2.1 of the License, or (at your option) any later version.

  This library 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
  Lesser General Public License for more details.

  You should have received a copy of the GNU Lesser General Public
  License along with this library; if not, write to the Free Software
  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
*/
/**
 * @file lib/connection_cleanup.c
 * @brief function to clean up completed connections
 * @author Christian Grothoff
 */
#include "internal.h"
#include "connection_cleanup.h"
#include "daemon_ip_limit.h"


#ifdef UPGRADE_SUPPORT
/**
 * Finally cleanup upgrade-related resources. It should
 * be called when TLS buffers have been drained and
 * application signaled MHD by #MHD_UPGRADE_ACTION_CLOSE.
 *
 * @param connection handle to the upgraded connection to clean
 */
static void
connection_cleanup_upgraded (struct MHD_Connection *connection)
{
  struct MHD_UpgradeResponseHandle *urh = connection->request.urh;

  if (NULL == urh)
    return;
#ifdef HTTPS_SUPPORT
  /* Signal remote client the end of TLS connection by
   * gracefully closing TLS session. */
  {
    struct MHD_TLS_Plugin *tls;

    if (NULL != (tls = connection->daemon->tls_api))
      (void) tls->shutdown_connection (tls->cls,
				       connection->tls_cs);
  }
  if (MHD_INVALID_SOCKET != urh->mhd.socket)
    MHD_socket_close_chk_ (urh->mhd.socket);
  if (MHD_INVALID_SOCKET != urh->app.socket)
    MHD_socket_close_chk_ (urh->app.socket);
#endif /* HTTPS_SUPPORT */
  connection->request.urh = NULL;
  free (urh);
}
#endif /* UPGRADE_SUPPORT */


/**
 * Free resources associated with all closed connections.  (destroy
 * responses, free buffers, etc.).  All closed connections are kept in
 * the "cleanup" doubly-linked list. 
 *
 * @remark To be called only from thread that process daemon's
 * select()/poll()/etc.
 *
 * @param daemon daemon to clean up
 */
void
MHD_connection_cleanup_ (struct MHD_Daemon *daemon)
{
  struct MHD_Connection *pos;

  MHD_mutex_lock_chk_ (&daemon->cleanup_connection_mutex);
  while (NULL != (pos = daemon->cleanup_tail))
    {
      DLL_remove (daemon->cleanup_head,
		  daemon->cleanup_tail,
		  pos);
      MHD_mutex_unlock_chk_ (&daemon->cleanup_connection_mutex);

      if ( (MHD_TM_THREAD_PER_CONNECTION == daemon->threading_mode) &&
	   (! pos->thread_joined) &&
           (! MHD_join_thread_ (pos->pid.handle)) )
        MHD_PANIC (_("Failed to join a thread\n"));
#ifdef UPGRADE_SUPPORT
      connection_cleanup_upgraded (pos);
#endif /* UPGRADE_SUPPORT */
      MHD_pool_destroy (pos->pool);
#ifdef HTTPS_SUPPORT
      {
	struct MHD_TLS_Plugin *tls;
	
	if (NULL != (tls = daemon->tls_api))
	  tls->teardown_connection (tls->cls,
				    pos->tls_cs);
      }
#endif /* HTTPS_SUPPORT */

      /* clean up the connection */
      if (NULL != daemon->notify_connection_cb)
        daemon->notify_connection_cb (daemon->notify_connection_cb_cls,
				      pos,
				      MHD_CONNECTION_NOTIFY_CLOSED);
      MHD_ip_limit_del (daemon,
                        (const struct sockaddr *) &pos->addr,
                        pos->addr_len);
#ifdef EPOLL_SUPPORT
      if (MHD_ELS_EPOLL == daemon->event_loop_syscall)
        {
          if (0 != (pos->epoll_state & MHD_EPOLL_STATE_IN_EREADY_EDLL))
            {
              EDLL_remove (daemon->eready_head,
                           daemon->eready_tail,
                           pos);
              pos->epoll_state &= ~MHD_EPOLL_STATE_IN_EREADY_EDLL;
            }
          if ( (-1 != daemon->epoll_fd) &&
               (0 != (pos->epoll_state & MHD_EPOLL_STATE_IN_EPOLL_SET)) )
            {
              /* epoll documentation suggests that closing a FD
                 automatically removes it from the epoll set; however,
                 this is not true as if we fail to do manually remove it,
                 we are still seeing an event for this fd in epoll,
                 causing grief (use-after-free...) --- at least on my
                 system. */
              if (0 != epoll_ctl (daemon->epoll_fd,
                                  EPOLL_CTL_DEL,
                                  pos->socket_fd,
                                  NULL))
                MHD_PANIC (_("Failed to remove FD from epoll set\n"));
              pos->epoll_state &= ~MHD_EPOLL_STATE_IN_EPOLL_SET;
            }
        }
#endif
      if (NULL != pos->request.response)
	{
	  MHD_response_queue_for_destroy (pos->request.response);
	  pos->request.response = NULL;
	}
      if (MHD_INVALID_SOCKET != pos->socket_fd)
        MHD_socket_close_chk_ (pos->socket_fd);
      free (pos);

      MHD_mutex_lock_chk_ (&daemon->cleanup_connection_mutex);
      daemon->connections--;
      daemon->at_limit = false;
    }
  MHD_mutex_unlock_chk_ (&daemon->cleanup_connection_mutex);
}

/* end of connection_cleanup.c */