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 Secure Component                                                 */
16 /**                                                                       */
17 /**    Transport Layer Security (TLS)                                     */
18 /**                                                                       */
19 /**************************************************************************/
20 /**************************************************************************/
21 
22 #define NX_SECURE_SOURCE_CODE
23 
24 #include "nx_secure_tls.h"
25 
26 /**************************************************************************/
27 /*                                                                        */
28 /*  FUNCTION                                               RELEASE        */
29 /*                                                                        */
30 /*    _nx_secure_tls_send_changecipherspec                PORTABLE C      */
31 /*                                                           6.1          */
32 /*  AUTHOR                                                                */
33 /*                                                                        */
34 /*    Timothy Stapko, Microsoft Corporation                               */
35 /*                                                                        */
36 /*  DESCRIPTION                                                           */
37 /*                                                                        */
38 /*    This function populates an NX_PACKET with the TLS ChangeCipherSpec  */
39 /*    message, which indicates that all further TLS records will be       */
40 /*    encrypted ussing the generated session keys.                        */
41 /*                                                                        */
42 /*  INPUT                                                                 */
43 /*                                                                        */
44 /*    tls_session                           TLS control block             */
45 /*    send_packet                           Packet to be filled           */
46 /*                                                                        */
47 /*  OUTPUT                                                                */
48 /*                                                                        */
49 /*    status                                Completion status             */
50 /*                                                                        */
51 /*  CALLS                                                                 */
52 /*                                                                        */
53 /*    None                                                                */
54 /*                                                                        */
55 /*  CALLED BY                                                             */
56 /*                                                                        */
57 /*    _nx_secure_dtls_client_handshake      DTLS client state machine     */
58 /*    _nx_secure_dtls_server_handshake      DTLS server state machine     */
59 /*    _nx_secure_tls_client_handshake       TLS client state machine      */
60 /*    _nx_secure_tls_server_handshake       TLS server state machine      */
61 /*                                                                        */
62 /*  RELEASE HISTORY                                                       */
63 /*                                                                        */
64 /*    DATE              NAME                      DESCRIPTION             */
65 /*                                                                        */
66 /*  05-19-2020     Timothy Stapko           Initial Version 6.0           */
67 /*  09-30-2020     Timothy Stapko           Modified comment(s),          */
68 /*                                            resulting in version 6.1    */
69 /*                                                                        */
70 /**************************************************************************/
_nx_secure_tls_send_changecipherspec(NX_SECURE_TLS_SESSION * tls_session,NX_PACKET * send_packet)71 UINT _nx_secure_tls_send_changecipherspec(NX_SECURE_TLS_SESSION *tls_session, NX_PACKET *send_packet)
72 {
73 
74     NX_PARAMETER_NOT_USED(tls_session);
75 
76     if (((ULONG)(send_packet -> nx_packet_data_end) - (ULONG)(send_packet -> nx_packet_append_ptr)) < 1u)
77     {
78 
79         /* Packet buffer is too small to hold random and ID. */
80         return(NX_SECURE_TLS_PACKET_BUFFER_TOO_SMALL);
81     }
82 
83     send_packet -> nx_packet_append_ptr[0] = 0x1;
84     send_packet -> nx_packet_append_ptr = send_packet -> nx_packet_append_ptr + 1;
85     send_packet -> nx_packet_length = 1;
86 
87     return(NX_SUCCESS);
88 }
89 
90