1 /***************************************************************************
2 * Copyright (c) 2024 Microsoft Corporation
3 *
4 * This program and the accompanying materials are made available under the
5 * terms of the MIT License which is available at
6 * https://opensource.org/licenses/MIT.
7 *
8 * SPDX-License-Identifier: MIT
9 **************************************************************************/
10
11
12 /**************************************************************************/
13 /**************************************************************************/
14 /** */
15 /** NetX Component */
16 /** */
17 /** Transmission Control Protocol (TCP) */
18 /** */
19 /**************************************************************************/
20 /**************************************************************************/
21
22 #define NX_SOURCE_CODE
23
24
25 /* Include necessary system files. */
26
27 #include "nx_api.h"
28 #include "nx_tcp.h"
29
30
31 /**************************************************************************/
32 /* */
33 /* FUNCTION RELEASE */
34 /* */
35 /* _nx_tcp_socket_mss_peer_get PORTABLE C */
36 /* 6.1 */
37 /* AUTHOR */
38 /* */
39 /* Yuxin Zhou, Microsoft Corporation */
40 /* */
41 /* DESCRIPTION */
42 /* */
43 /* This function retrieves TCP Maximum Segment Size (MSS) of the */
44 /* peer connected to the specified TCP socket. */
45 /* */
46 /* INPUT */
47 /* */
48 /* socket_ptr Pointer to the TCP socket */
49 /* peer_mss Destination for the MSS */
50 /* */
51 /* OUTPUT */
52 /* */
53 /* status Completion status */
54 /* */
55 /* CALLS */
56 /* */
57 /* tx_mutex_get Obtain protection */
58 /* tx_mutex_put Release protection */
59 /* */
60 /* CALLED BY */
61 /* */
62 /* Application Code */
63 /* */
64 /* RELEASE HISTORY */
65 /* */
66 /* DATE NAME DESCRIPTION */
67 /* */
68 /* 05-19-2020 Yuxin Zhou Initial Version 6.0 */
69 /* 09-30-2020 Yuxin Zhou Modified comment(s), */
70 /* resulting in version 6.1 */
71 /* */
72 /**************************************************************************/
_nx_tcp_socket_mss_peer_get(NX_TCP_SOCKET * socket_ptr,ULONG * peer_mss)73 UINT _nx_tcp_socket_mss_peer_get(NX_TCP_SOCKET *socket_ptr, ULONG *peer_mss)
74 {
75
76 NX_IP *ip_ptr;
77
78
79 /* Setup IP pointer. */
80 ip_ptr = socket_ptr -> nx_tcp_socket_ip_ptr;
81
82 /* If trace is enabled, insert this event into the trace buffer. */
83 NX_TRACE_IN_LINE_INSERT(NX_TRACE_TCP_SOCKET_MSS_PEER_GET, ip_ptr, socket_ptr, socket_ptr -> nx_tcp_socket_peer_mss, socket_ptr -> nx_tcp_socket_state, NX_TRACE_TCP_EVENTS, 0, 0);
84
85 /* Obtain the IP mutex so we can examine the bound port. */
86 tx_mutex_get(&(ip_ptr -> nx_ip_protection), TX_WAIT_FOREVER);
87
88 /* Pickup socket's peer MSS value. */
89 *peer_mss = socket_ptr -> nx_tcp_socket_peer_mss;
90
91 /* Release protection. */
92 tx_mutex_put(&(ip_ptr -> nx_ip_protection));
93
94 /* Return successful completion status. */
95 return(NX_SUCCESS);
96 }
97
98