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 "tx_thread.h"
31
32
33 /**************************************************************************/
34 /* */
35 /* FUNCTION RELEASE */
36 /* */
37 /* _nx_tcp_client_socket_bind PORTABLE C */
38 /* 6.1.11 */
39 /* AUTHOR */
40 /* */
41 /* Yuxin Zhou, Microsoft Corporation */
42 /* */
43 /* DESCRIPTION */
44 /* */
45 /* This function binds the TCP socket structure to a specific TCP */
46 /* port. */
47 /* */
48 /* INPUT */
49 /* */
50 /* socket_ptr Pointer to TCP socket */
51 /* port 16-bit TCP port number */
52 /* wait_option Suspension option */
53 /* */
54 /* OUTPUT */
55 /* */
56 /* status Completion status */
57 /* */
58 /* CALLS */
59 /* */
60 /* _nx_tcp_free_port_find Find free TCP port */
61 /* _nx_tcp_socket_thread_suspend Suspend thread */
62 /* tx_mutex_get Obtain protection mutex */
63 /* tx_mutex_put Release protection mutex */
64 /* */
65 /* CALLED BY */
66 /* */
67 /* Application Code */
68 /* */
69 /* RELEASE HISTORY */
70 /* */
71 /* DATE NAME DESCRIPTION */
72 /* */
73 /* 05-19-2020 Yuxin Zhou Initial Version 6.0 */
74 /* 09-30-2020 Yuxin Zhou Modified comment(s), */
75 /* resulting in version 6.1 */
76 /* 04-25-2022 Yuxin Zhou Modified comment(s), and */
77 /* corrected the random value, */
78 /* resulting in version 6.1.11 */
79 /* */
80 /**************************************************************************/
_nx_tcp_client_socket_bind(NX_TCP_SOCKET * socket_ptr,UINT port,ULONG wait_option)81 UINT _nx_tcp_client_socket_bind(NX_TCP_SOCKET *socket_ptr, UINT port, ULONG wait_option)
82 {
83 TX_INTERRUPT_SAVE_AREA
84
85 UINT index;
86 #ifdef NX_NAT_ENABLE
87 UINT bound;
88 #endif /* NX_NAT_ENABLE */
89 NX_IP *ip_ptr;
90 NX_TCP_SOCKET *search_ptr;
91 NX_TCP_SOCKET *end_ptr;
92
93
94 /* Setup the pointer to the associated IP instance. */
95 ip_ptr = socket_ptr -> nx_tcp_socket_ip_ptr;
96
97 /* If trace is enabled, insert this event into the trace buffer. */
98 NX_TRACE_IN_LINE_INSERT(NX_TRACE_TCP_CLIENT_SOCKET_BIND, ip_ptr, socket_ptr, port, wait_option, NX_TRACE_TCP_EVENTS, 0, 0);
99
100 /* Obtain the IP mutex so we can figure out whether or not the port has already
101 been bound to. */
102 tx_mutex_get(&(ip_ptr -> nx_ip_protection), TX_WAIT_FOREVER);
103
104 /* Determine if the socket has already been bound to port or if a socket bind is
105 already pending from another thread. */
106 if ((socket_ptr -> nx_tcp_socket_bound_next) ||
107 (socket_ptr -> nx_tcp_socket_bind_in_progress))
108 {
109
110 /* Release the protection mutex. */
111 tx_mutex_put(&(ip_ptr -> nx_ip_protection));
112
113 /* Return an already bound error code. */
114 return(NX_ALREADY_BOUND);
115 }
116
117 /* Determine if the port needs to be allocated. */
118 if (port == NX_ANY_PORT)
119 {
120
121 /* Call the find routine to allocate a TCP port. */
122 port = NX_SEARCH_PORT_START + (UINT)(((ULONG)NX_RAND()) % ((NX_MAX_PORT + 1) - NX_SEARCH_PORT_START));
123 if (_nx_tcp_free_port_find(ip_ptr, port, &port) != NX_SUCCESS)
124 {
125
126 /* Release the protection mutex. */
127 tx_mutex_put(&(ip_ptr -> nx_ip_protection));
128
129 /* There was no free port, return an error code. */
130 return(NX_NO_FREE_PORTS);
131 }
132 }
133 #ifdef NX_NAT_ENABLE
134 else
135 {
136
137 /* Check if this IP interface has a NAT service. */
138 if (ip_ptr -> nx_ip_nat_port_verify)
139 {
140
141 /* Yes, so check the port by NAT handler. If NAT does not use this port, allow NetX to use it. */
142 bound = (ip_ptr -> nx_ip_nat_port_verify)(ip_ptr, NX_PROTOCOL_TCP, port);
143
144 /* Check to see if the port has been used by NAT. */
145 if (bound == NX_TRUE)
146 {
147
148 /* Release the protection. */
149 tx_mutex_put(&(ip_ptr -> nx_ip_protection));
150
151 /* Return the port unavailable error. */
152 return(NX_PORT_UNAVAILABLE);
153 }
154 }
155 }
156 #endif
157
158 /* Save the port number in the TCP socket structure. */
159 socket_ptr -> nx_tcp_socket_port = port;
160
161 /* Calculate the hash index in the TCP port array of the associated IP instance. */
162 index = (UINT)((port + (port >> 8)) & NX_TCP_PORT_TABLE_MASK);
163
164 /* Pickup the head of the TCP ports bound list. */
165 search_ptr = ip_ptr -> nx_ip_tcp_port_table[index];
166
167 /* Determine if we need to perform a list search. */
168 if (search_ptr)
169 {
170
171 /* Walk through the circular list of TCP sockets that are already
172 bound. */
173 end_ptr = search_ptr;
174 do
175 {
176
177 /* Determine if this entry is the same as the requested port. */
178 if (search_ptr -> nx_tcp_socket_port == port)
179 {
180
181 /* Yes, the port has already been allocated. */
182 break;
183 }
184
185 /* Move to the next entry in the list. */
186 search_ptr = search_ptr -> nx_tcp_socket_bound_next;
187 } while (search_ptr != end_ptr);
188 }
189
190 /* Now determine if the port is available. */
191 if ((search_ptr == NX_NULL) || (search_ptr -> nx_tcp_socket_port != port))
192 {
193
194 /* Place this TCP socket structure on the list of bound ports. */
195
196 /* Disable interrupts. */
197 TX_DISABLE
198
199 /* Determine if the list is NULL. */
200 if (search_ptr)
201 {
202
203 /* There are already sockets on this list... just add this one
204 to the end. */
205 socket_ptr -> nx_tcp_socket_bound_next =
206 ip_ptr -> nx_ip_tcp_port_table[index];
207 socket_ptr -> nx_tcp_socket_bound_previous =
208 (ip_ptr -> nx_ip_tcp_port_table[index]) -> nx_tcp_socket_bound_previous;
209 ((ip_ptr -> nx_ip_tcp_port_table[index]) -> nx_tcp_socket_bound_previous) -> nx_tcp_socket_bound_next =
210 socket_ptr;
211 (ip_ptr -> nx_ip_tcp_port_table[index]) -> nx_tcp_socket_bound_previous = socket_ptr;
212 }
213 else
214 {
215
216 /* Nothing is on the TCP port list. Add this TCP socket to an
217 empty list. */
218 socket_ptr -> nx_tcp_socket_bound_next = socket_ptr;
219 socket_ptr -> nx_tcp_socket_bound_previous = socket_ptr;
220 ip_ptr -> nx_ip_tcp_port_table[index] = socket_ptr;
221 }
222
223 /* Restore interrupts. */
224 TX_RESTORE
225
226 /* Release the mutex protection. */
227 tx_mutex_put(&(ip_ptr -> nx_ip_protection));
228
229 /* Return success to the caller. */
230 return(NX_SUCCESS);
231 }
232 else if (wait_option)
233 {
234
235 /* Prepare for suspension of this thread. */
236
237 /* Increment the suspended thread count. */
238 search_ptr -> nx_tcp_socket_bind_suspended_count++;
239
240 /* Set the socket bind in progress flag (thread pointer). */
241 socket_ptr -> nx_tcp_socket_bind_in_progress = _tx_thread_current_ptr;
242
243 /* Also remember the socket that has bound to the port, since the thread
244 is going to be suspended on that socket. */
245 socket_ptr -> nx_tcp_socket_bound_previous = search_ptr;
246
247 /* Suspend the thread on this socket's connection attempt. */
248 _nx_tcp_socket_thread_suspend(&(search_ptr -> nx_tcp_socket_bind_suspension_list), _nx_tcp_client_bind_cleanup, socket_ptr, &(ip_ptr -> nx_ip_protection), wait_option);
249
250 /* Return the completion status. */
251 return(_tx_thread_current_ptr -> tx_thread_suspend_status);
252 }
253 else
254 {
255
256 /* Release the IP protection. */
257 tx_mutex_put(&(ip_ptr -> nx_ip_protection));
258
259 /* Return the port unavailable error. */
260 return(NX_PORT_UNAVAILABLE);
261 }
262 }
263
264
