Outline ![]()
Files ![]()
loading (6/7)...
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
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
/**************************************************************************/
/* */
/* Copyright (c) Microsoft Corporation. All rights reserved. */
/* */
/* This software is licensed under the Microsoft Software License */
/* Terms for Microsoft Azure RTOS. Full text of the license can be */
/* found in the LICENSE file at https://aka.ms/AzureRTOS_EULA */
/* and in the root directory of this software. */
/* */
/**************************************************************************/
/**************************************************************************/
/**************************************************************************/
/** */
/** NetX Secure Component */
/** */
/** Transport Layer Security (TLS) */
/** */
/**************************************************************************/
/**************************************************************************/
#define NX_SECURE_SOURCE_CODE
#include "nx_secure_tls.h"
/* We need to access the supported versions table located in nx_secure_tls_check_protocol_version.c. */
extern const NX_SECURE_VERSIONS_LIST nx_secure_supported_versions_list[];
/**************************************************************************/
/* */
/* FUNCTION RELEASE */
/* */
/* _nx_secure_tls_newest_supported_version PORTABLE C */
/* 6.1 */
/* AUTHOR */
/* */
/* Timothy Stapko, Microsoft Corporation */
/* */
/* DESCRIPTION */
/* */
/* Return the newest currently supported and enabled TLS/DTLS protocol */
/* version. This enables the backward-compatible TLS/DTLS handshake */
/* and forces the upgrade to the latest supported TLS/DTLS version. */
/* */
/* INPUT */
/* */
/* session_ptr TLS session */
/* protocol_version Pointer to version variable */
/* id TLS or DTLS */
/* */
/* OUTPUT */
/* */
/* None */
/* */
/* CALLS */
/* */
/* None */
/* */
/* CALLED BY */
/* */
/* _nx_secure_dtls_send_clienthello Send ClientHello */
/* _nx_secure_tls_process_clienthello Process ClientHello */
/* _nx_secure_tls_send_clienthello Send ClientHello */
/* _nx_secure_tls_protocol_version_get Get current TLS version to use*/
/* */
/* RELEASE HISTORY */
/* */
/* DATE NAME DESCRIPTION */
/* */
/* 05-19-2020 Timothy Stapko Initial Version 6.0 */
/* 09-30-2020 Timothy Stapko Modified comment(s), */
/* resulting in version 6.1 */
/* */
/**************************************************************************/
VOID _nx_secure_tls_newest_supported_version(NX_SECURE_TLS_SESSION *session_ptr,
USHORT *protocol_version, UINT id)
{
INT i;
NX_PARAMETER_NOT_USED(session_ptr);
#ifndef NX_SECURE_TLS_SERVER_DISABLED
if(session_ptr -> nx_secure_tls_socket_type == NX_SECURE_TLS_SESSION_TYPE_SERVER &&
session_ptr -> nx_secure_tls_protocol_version_override != 0)
{
/* If this is a server and the user has overriden the protocol version,
THAT version is now the higest supported. */
(*protocol_version) = session_ptr -> nx_secure_tls_protocol_version_override;
return;
}
#endif
/* Table is in order of oldest to newest, so walk backward to get
* the newest version we support. */
for (i = (INT)(nx_secure_supported_versions_list[id].nx_secure_versions_list_count - 1); i >= 0; --i)
{
/* If the version is supported, return it. */
if (nx_secure_supported_versions_list[id].nx_secure_versions_list[i].nx_secure_tls_is_supported)
{
(*protocol_version) = nx_secure_supported_versions_list[id].nx_secure_versions_list[i].nx_secure_tls_protocol_version;
return;
}
}
/* If we get here, no versions of TLS have been enabled. Set protocol to 0 to indicate failure. */
(*protocol_version) = 0x0;
return;
}
/**************************************************************************/
/* */
/* FUNCTION RELEASE */
/* */
/* _nx_secure_tls_highest_supported_version_negotiate PORTABLE C */
/* 6.1 */
/* AUTHOR */
/* */
/* Timothy Stapko, Microsoft Corporation */
/* */
/* DESCRIPTION */
/* */
/* Negotiate the highested supported and enabled TLS/DTLS protocol */
/* version, if the protocol version in clientHello is not supported */
/* by the server. */
/* */
/* INPUT */
/* */
/* session_ptr TLS session */
/* protocol_version Pointer to version variable */
/* id TLS or DTLS */
/* */
/* OUTPUT */
/* */
/* None */
/* */
/* CALLS */
/* */
/* None */
/* */
/* CALLED BY */
/* */
/* _nx_secure_dtls_process_clienthello Send ClientHello */
/* _nx_secure_tls_process_clienthello Process ClientHello */
/* */
/* RELEASE HISTORY */
/* */
/* DATE NAME DESCRIPTION */
/* */
/* 09-30-2020 Timothy Stapko Initial Version 6.1 */
/* */
/**************************************************************************/
void _nx_secure_tls_highest_supported_version_negotiate(NX_SECURE_TLS_SESSION *session_ptr,
USHORT *protocol_version, UINT id)
{
INT i;
USHORT highest_version = 0;
USHORT lowest_version = 0xFF;
USHORT highest_version_not_greater_than_client_version = 0;
NX_PARAMETER_NOT_USED(session_ptr);
#ifndef NX_SECURE_TLS_SERVER_DISABLED
if(session_ptr -> nx_secure_tls_socket_type == NX_SECURE_TLS_SESSION_TYPE_SERVER &&
session_ptr -> nx_secure_tls_negotiated_highest_protocol_version != 0)
{
/* If this is a server and the user has the negotiated highest version,
return it directly. */
(*protocol_version) = session_ptr -> nx_secure_tls_negotiated_highest_protocol_version;
return;
}
#endif
/* Find the highest and the lowest supported server version. */
for (i = (INT)(nx_secure_supported_versions_list[id].nx_secure_versions_list_count - 1); i >= 0; --i)
{
/* If the version is supported, return it. */
if (nx_secure_supported_versions_list[id].nx_secure_versions_list[i].nx_secure_tls_is_supported)
{
if (highest_version < nx_secure_supported_versions_list[id].nx_secure_versions_list[i].nx_secure_tls_protocol_version)
{
highest_version = nx_secure_supported_versions_list[id].nx_secure_versions_list[i].nx_secure_tls_protocol_version;
}
if (lowest_version > nx_secure_supported_versions_list[id].nx_secure_versions_list[i].nx_secure_tls_protocol_version)
{
lowest_version = nx_secure_supported_versions_list[id].nx_secure_versions_list[i].nx_secure_tls_protocol_version;
}
if (!highest_version_not_greater_than_client_version &&
(*protocol_version) >= nx_secure_supported_versions_list[id].nx_secure_versions_list[i].nx_secure_tls_protocol_version)
{
highest_version_not_greater_than_client_version = nx_secure_supported_versions_list[id].nx_secure_versions_list[i].nx_secure_tls_protocol_version;
}
}
}
/* No versions of TLS have been enabled. Set protocol to 0 to indicate failure. */
if (highest_version == 0)
{
(*protocol_version) = 0;
session_ptr -> nx_secure_tls_negotiated_highest_protocol_version = 0;
return;
}
/* According to RFC 5246 E.1,
if protocol_version > highest_version, set protocol_version to highest_version to indicate to send "server_hello" with highest_version;
if lowest_version < protocol_version < highest_version, set protocol_version to the highest server version not greater than protocol_version;
if protocol_version < lowest_version, set protocol_version to 0 to indicate to send a "protocol_version" alert message.
*/
if ((*protocol_version) > highest_version)
{
(*protocol_version) = highest_version;
}
else
{
if ((*protocol_version) < highest_version && (*protocol_version) > lowest_version)
{
(*protocol_version) = highest_version_not_greater_than_client_version;
}
else
{
(*protocol_version) = 0;
}
}
session_ptr -> nx_secure_tls_negotiated_highest_protocol_version = (*protocol_version);
return;
}
Details ![]()
Show: from Types: Columns: ![]( "Show Project Names")
![]( "Show Locations")
![]( "Show Referring Symbols")
![]( "Show Scope")
This file uses the notable symbols shown below. Click anywhere in the file to view more details.