1 /**************************************************************************/
2 /* */
3 /* Copyright (c) Microsoft Corporation. All rights reserved. */
4 /* */
5 /* This software is licensed under the Microsoft Software License */
6 /* Terms for Microsoft Azure RTOS. Full text of the license can be */
7 /* found in the LICENSE file at https://aka.ms/AzureRTOS_EULA */
8 /* and in the root directory of this software. */
9 /* */
10 /**************************************************************************/
11
12
13 /**************************************************************************/
14 /**************************************************************************/
15 /** */
16 /** NetX Component */
17 /** */
18 /** Transmission Control Protocol (TCP) */
19 /** */
20 /**************************************************************************/
21 /**************************************************************************/
22
23 #define NX_SOURCE_CODE
24
25
26 /* Include necessary system files. */
27
28 #include "nx_api.h"
29 #include "nx_tcp.h"
30 #include "nx_ipv6.h"
31
32 /**************************************************************************/
33 /* */
34 /* FUNCTION RELEASE */
35 /* */
36 /* _nx_tcp_server_socket_unaccept PORTABLE C */
37 /* 6.1 */
38 /* AUTHOR */
39 /* */
40 /* Yuxin Zhou, Microsoft Corporation */
41 /* */
42 /* DESCRIPTION */
43 /* */
44 /* This function removes the server socket from association with the */
45 /* port receiving an earlier passive connection. It is left in a */
46 /* state identical to the state after it was created. */
47 /* */
48 /* INPUT */
49 /* */
50 /* socket_ptr Pointer to new TCP socket */
51 /* */
52 /* OUTPUT */
53 /* */
54 /* status Completion status */
55 /* */
56 /* CALLS */
57 /* */
58 /* _nx_tcp_socket_receive_queue_flush Release all receive packets */
59 /* tx_mutex_get Obtain a protection mutex */
60 /* tx_mutex_put Release a protection mutex */
61 /* */
62 /* CALLED BY */
63 /* */
64 /* Application Code */
65 /* */
66 /* RELEASE HISTORY */
67 /* */
68 /* DATE NAME DESCRIPTION */
69 /* */
70 /* 05-19-2020 Yuxin Zhou Initial Version 6.0 */
71 /* 09-30-2020 Yuxin Zhou Modified comment(s), */
72 /* resulting in version 6.1 */
73 /* */
74 /**************************************************************************/
_nx_tcp_server_socket_unaccept(NX_TCP_SOCKET * socket_ptr)75 UINT _nx_tcp_server_socket_unaccept(NX_TCP_SOCKET *socket_ptr)
76 {
77
78 struct NX_TCP_LISTEN_STRUCT *listen_ptr;
79 NX_IP *ip_ptr;
80 UINT index;
81 UINT port;
82
83
84 /* Pickup the associated IP structure. */
85 ip_ptr = socket_ptr -> nx_tcp_socket_ip_ptr;
86
87 /* If trace is enabled, insert this event into the trace buffer. */
88 NX_TRACE_IN_LINE_INSERT(NX_TRACE_TCP_SERVER_SOCKET_UNACCEPT, ip_ptr, socket_ptr, socket_ptr -> nx_tcp_socket_state, 0, NX_TRACE_TCP_EVENTS, 0, 0);
89
90 /* Obtain the IP mutex so we can access the IP and socket data structures. */
91 tx_mutex_get(&(ip_ptr -> nx_ip_protection), TX_WAIT_FOREVER);
92
93 /* Determine if the socket is in a state of disconnect. */
94 if ((socket_ptr -> nx_tcp_socket_state >= NX_TCP_CLOSE_WAIT) ||
95 ((socket_ptr -> nx_tcp_socket_state == NX_TCP_CLOSED) && (socket_ptr -> nx_tcp_socket_bound_next)))
96 {
97
98 /* If trace is enabled, insert this event into the trace buffer. */
99 NX_TRACE_IN_LINE_INSERT(NX_TRACE_INTERNAL_TCP_STATE_CHANGE, ip_ptr, socket_ptr, socket_ptr -> nx_tcp_socket_state, NX_TCP_LISTEN_STATE, NX_TRACE_INTERNAL_EVENTS, 0, 0);
100
101 /* Force to the listen state. */
102 socket_ptr -> nx_tcp_socket_state = NX_TCP_LISTEN_STATE;
103
104 /* Ensure the connect information is cleared. */
105 socket_ptr -> nx_tcp_socket_connect_ip.nxd_ip_version = 0;
106 #ifdef FEATURE_NX_IPV6
107 /* Zero out the IP address entry. */
108 SET_UNSPECIFIED_ADDRESS(socket_ptr -> nx_tcp_socket_connect_ip.nxd_ip_address.v6);
109 #else /* FEATURE_NX_IPV6 */
110 socket_ptr -> nx_tcp_socket_connect_ip.nxd_ip_address.v4 = 0;
111 #endif /* FEATURE_NX_IPV6 */
112
113 socket_ptr -> nx_tcp_socket_connect_port = 0;
114 }
115
116 /* Determine if the socket is in the listen state now. */
117 if (socket_ptr -> nx_tcp_socket_state != NX_TCP_LISTEN_STATE)
118 {
119
120 /* Release the IP protection. */
121 tx_mutex_put(&(ip_ptr -> nx_ip_protection));
122
123 /* Return an error code. */
124 return(NX_NOT_LISTEN_STATE);
125 }
126
127 /* Check for a thread suspended for disconnect processing to complete. */
128 if (socket_ptr -> nx_tcp_socket_disconnect_suspended_thread)
129 {
130
131 /* Call the disconnect thread suspension cleanup routine. */
132 _nx_tcp_disconnect_cleanup(socket_ptr -> nx_tcp_socket_disconnect_suspended_thread NX_CLEANUP_ARGUMENT);
133 }
134
135 /* Remove the TCP socket form the associated port. */
136
137 /* Pickup the port number in the TCP socket structure. */
138 port = socket_ptr -> nx_tcp_socket_port;
139
140 /* Calculate the hash index in the TCP port array of the associated IP instance. */
141 index = (UINT)((port + (port >> 8)) & NX_TCP_PORT_TABLE_MASK);
142
143 /* Determine if this is the only socket bound on this port list. */
144 if (socket_ptr -> nx_tcp_socket_bound_next == socket_ptr)
145 {
146
147 /* Yes, this is the only socket on the port list. */
148
149 /* Clear the list head pointer and the next pointer in the socket. */
150 ip_ptr -> nx_ip_tcp_port_table[index] = NX_NULL;
151 socket_ptr -> nx_tcp_socket_bound_next = NX_NULL;
152 }
153 else if (socket_ptr -> nx_tcp_socket_bound_next)
154 {
155
156 /* Relink the neighbors of this TCP socket. */
157
158 /* Update the links of the adjacent sockets. */
159 (socket_ptr -> nx_tcp_socket_bound_next) -> nx_tcp_socket_bound_previous = socket_ptr -> nx_tcp_socket_bound_previous;
160 (socket_ptr -> nx_tcp_socket_bound_previous) -> nx_tcp_socket_bound_next = socket_ptr -> nx_tcp_socket_bound_next;
161
162 /* Determine if the head of the port list points to the socket being removed.
163 If so, we need to move the head pointer. */
164 if (ip_ptr -> nx_ip_tcp_port_table[index] == socket_ptr)
165 {
166
167 /* Yes, we need to move the port list head pointer. */
168 ip_ptr -> nx_ip_tcp_port_table[index] = socket_ptr -> nx_tcp_socket_bound_next;
169 }
170
171 /* Clear the next pointer in the socket to indicate it is no longer bound. */
172 socket_ptr -> nx_tcp_socket_bound_next = NX_NULL;
173 }
174 else
175 {
176
177 /* Not bound, so search through the active listen requests to see if this
178 socket is an active listen socket. */
179 listen_ptr = ip_ptr -> nx_ip_tcp_active_listen_requests;
180 if (listen_ptr)
181 {
182
183 /* Search the active listen requests for this port. */
184 do
185 {
186
187 /* Determine if we are releasing a socket that is listening. */
188 if (listen_ptr -> nx_tcp_listen_socket_ptr == socket_ptr)
189 {
190
191 /* Remove the socket from the listener. A relisten will be required to receive another
192 connection. */
193 listen_ptr -> nx_tcp_listen_socket_ptr = NX_NULL;
194 break;
195 }
196
197 /* Move to the next listen request. */
198 listen_ptr = listen_ptr -> nx_tcp_listen_next;
199 } while (listen_ptr != ip_ptr -> nx_ip_tcp_active_listen_requests);
200 }
201 }
202
203 /* If trace is enabled, insert this event into the trace buffer. */
204 NX_TRACE_IN_LINE_INSERT(NX_TRACE_INTERNAL_TCP_STATE_CHANGE, ip_ptr, socket_ptr, socket_ptr -> nx_tcp_socket_state, NX_TCP_CLOSED, NX_TRACE_INTERNAL_EVENTS, 0, 0);
205
206 /* Adjust the socket back to default states. */
207 socket_ptr -> nx_tcp_socket_state = NX_TCP_CLOSED;
208 socket_ptr -> nx_tcp_socket_client_type = NX_TRUE;
209
210 /* Socket is no longer active. Clear the timeout. */
211 socket_ptr -> nx_tcp_socket_timeout = 0;
212
213 /* The socket is off the bound list... we need to check for queued receive packets and
214 if found they need to be released. */
215 if (socket_ptr -> nx_tcp_socket_receive_queue_count)
216 {
217
218 /* Release queued receive packets. */
219 _nx_tcp_socket_receive_queue_flush(socket_ptr);
220 }
221
222 /* Release the IP protection. */
223 tx_mutex_put(&(ip_ptr -> nx_ip_protection));
224
225 /* Return success. */
226 return(NX_SUCCESS);
227 }
228
229
