summaryrefslogtreecommitdiff
path: root/common/src/nx_tcp_socket_state_closing.c
blob: 22ab887a36531961236d53185fd5ec6fbb41cb65 (plain)
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
/***************************************************************************
 * Copyright (c) 2024 Microsoft Corporation
 * Copyright (c) 2025-present Eclipse ThreadX Contributors
 *
 * This program and the accompanying materials are made available under the
 * terms of the MIT License which is available at
 * https://opensource.org/licenses/MIT.
 *
 * SPDX-License-Identifier: MIT
 **************************************************************************/


/**************************************************************************/
/**************************************************************************/
/**                                                                       */
/** NetX Component                                                        */
/**                                                                       */
/**   Transmission Control Protocol (TCP)                                 */
/**                                                                       */
/**************************************************************************/
/**************************************************************************/

#define NX_SOURCE_CODE


/* Include necessary system files.  */

#include "nx_api.h"
#include "nx_tcp.h"
#include "nx_ipv6.h"

/**************************************************************************/
/*                                                                        */
/*  FUNCTION                                               RELEASE        */
/*                                                                        */
/*    _nx_tcp_socket_state_closing                        PORTABLE C      */
/*                                                           6.4.3        */
/*  AUTHOR                                                                */
/*                                                                        */
/*    Yuxin Zhou, Microsoft Corporation                                   */
/*                                                                        */
/*  DESCRIPTION                                                           */
/*                                                                        */
/*    This function processes packets during the CLOSING state,           */
/*    which is the state at the end of an active, simultaneous            */
/*    disconnect.  If a valid ACK is present, set the socket state        */
/*    to TIMED WAIT.                                                      */
/*                                                                        */
/*  INPUT                                                                 */
/*                                                                        */
/*    socket_ptr                            Pointer to owning socket      */
/*    tcp_header_ptr                        Pointer to packet header      */
/*                                                                        */
/*  OUTPUT                                                                */
/*                                                                        */
/*    None                                                                */
/*                                                                        */
/*  CALLS                                                                 */
/*                                                                        */
/*    _nx_tcp_packet_send_ack               Send ACK message              */
/*                                                                        */
/*  CALLED BY                                                             */
/*                                                                        */
/*    _nx_tcp_socket_packet_process         Process TCP packet for socket */
/*                                                                        */
/**************************************************************************/
VOID  _nx_tcp_socket_state_closing(NX_TCP_SOCKET *socket_ptr, NX_TCP_HEADER *tcp_header_ptr)
{


    /* Determine if the incoming message is an ACK message.  */
    if (tcp_header_ptr -> nx_tcp_header_word_3 & NX_TCP_ACK_BIT)
    {

        /* If it is proper, finish the disconnect. */
        if ((tcp_header_ptr -> nx_tcp_acknowledgment_number == socket_ptr -> nx_tcp_socket_tx_sequence) &&
            (tcp_header_ptr -> nx_tcp_sequence_number == socket_ptr -> nx_tcp_socket_rx_sequence))
        {

            /* Return to the proper socket state.  */

            /* Yes, return the socket to the TIMED WAIT state. */

            /* If trace is enabled, insert this event into the trace buffer.  */
            NX_TRACE_IN_LINE_INSERT(NX_TRACE_INTERNAL_TCP_STATE_CHANGE, socket_ptr -> nx_tcp_socket_ip_ptr, socket_ptr, socket_ptr -> nx_tcp_socket_state, NX_TCP_TIMED_WAIT, NX_TRACE_INTERNAL_EVENTS, 0, 0);

            /* Set the socket state to TIMED WAIT now.  */
            socket_ptr -> nx_tcp_socket_state = NX_TCP_TIMED_WAIT;

            /* Set the timeout as 2MSL (Maximum Segment Lifetime). */
            socket_ptr -> nx_tcp_socket_timeout = _nx_tcp_2MSL_timer_rate;

            /* Determine if we need to wake a thread suspended on the connection.  */
            if (socket_ptr -> nx_tcp_socket_disconnect_suspended_thread)
            {

                /* Resume the thread suspended for the disconnect.  */
                _nx_tcp_socket_thread_resume(&(socket_ptr -> nx_tcp_socket_disconnect_suspended_thread), NX_SUCCESS);
            }

            /* If given, call the application's disconnect callback function
               for disconnect.  */
            if (socket_ptr -> nx_tcp_disconnect_callback)
            {

                /* Call the application's disconnect handling function.  It is
                   responsible for calling the socket disconnect function.  */
                (socket_ptr -> nx_tcp_disconnect_callback)(socket_ptr);
            }

#ifndef NX_DISABLE_EXTENDED_NOTIFY_SUPPORT

            /* Is a timed wait callback registered for this socket?  */
            if (socket_ptr -> nx_tcp_timed_wait_callback)
            {

                /* Call the timed wait callback for this socket to let the host
                   know the socket can now be put in the timed wait state (if
                   the RE-USE ADDRESS socket option is not enabled). */
                (socket_ptr -> nx_tcp_timed_wait_callback)(socket_ptr);
            }

            /* Is a disconnect complete callback registered with the TCP socket? */
            if (socket_ptr -> nx_tcp_disconnect_complete_notify)
            {

                /* Call the application's disconnect_complete callback function.    */
                (socket_ptr -> nx_tcp_disconnect_complete_notify)(socket_ptr);
            }
#endif
        }

        /* Ignore the segment.  According to RFC 793, Section 3.9, Page 73.  */
    }
}