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
25 #include "nx_secure_tls.h"
26
27 /**************************************************************************/
28 /* */
29 /* FUNCTION RELEASE */
30 /* */
31 /* _nx_secure_tls_process_header PORTABLE C */
32 /* 6.1 */
33 /* AUTHOR */
34 /* */
35 /* Timothy Stapko, Microsoft Corporation */
36 /* */
37 /* DESCRIPTION */
38 /* */
39 /* This function processes an NX_PACKET data structure, extracting */
40 /* and parsing a TLS header received from a remote host. */
41 /* */
42 /* INPUT */
43 /* */
44 /* tls_session Pointer to TLS control block */
45 /* packet_ptr Pointer to incoming packet */
46 /* record_offset Offset of current record */
47 /* message_type Return message type value */
48 /* length Return message length value */
49 /* header_data Pointer to header to parse */
50 /* header_length Length of header data (bytes) */
51 /* */
52 /* OUTPUT */
53 /* */
54 /* status Completion status */
55 /* */
56 /* CALLS */
57 /* */
58 /* nx_packet_data_extract_offset Extract data from NX_PACKET */
59 /* _nx_secure_tls_check_protocol_version Check incoming TLS version */
60 /* */
61 /* CALLED BY */
62 /* */
63 /* _nx_secure_tls_process_record Process TLS record */
64 /* */
65 /* RELEASE HISTORY */
66 /* */
67 /* DATE NAME DESCRIPTION */
68 /* */
69 /* 05-19-2020 Timothy Stapko Initial Version 6.0 */
70 /* 09-30-2020 Timothy Stapko Modified comment(s), */
71 /* supported chained packet, */
72 /* resulting in version 6.1 */
73 /* */
74 /**************************************************************************/
_nx_secure_tls_process_header(NX_SECURE_TLS_SESSION * tls_session,NX_PACKET * packet_ptr,ULONG record_offset,USHORT * message_type,UINT * length,UCHAR * header_data,USHORT * header_length)75 UINT _nx_secure_tls_process_header(NX_SECURE_TLS_SESSION *tls_session, NX_PACKET *packet_ptr,
76 ULONG record_offset, USHORT *message_type, UINT *length,
77 UCHAR *header_data, USHORT *header_length)
78 {
79 ULONG bytes_copied;
80 UINT status;
81 USHORT protocol_version;
82
83
84 /* Check the packet. */
85 if (packet_ptr == NX_NULL)
86 {
87
88 /* There was an error in extracting the header from the supplied packet. */
89 return(NX_SECURE_TLS_INVALID_PACKET);
90 }
91
92 /* Process the TLS record header, which will set the state. */
93 status = nx_packet_data_extract_offset(packet_ptr, record_offset, header_data,
94 NX_SECURE_TLS_RECORD_HEADER_SIZE, &bytes_copied);
95
96 /* Make sure we actually got a header. */
97 if (status != NX_SUCCESS)
98 {
99
100 /* There was an error in extracting the header from the supplied packet. */
101 return(NX_SECURE_TLS_INVALID_PACKET);
102 }
103
104 if (bytes_copied != NX_SECURE_TLS_RECORD_HEADER_SIZE)
105 {
106
107 /* Wait more TCP packets for this one record. */
108 return(NX_CONTINUE);
109 }
110
111 /* Extract message type from packet/record. */
112 *message_type = header_data[0];
113
114 /* Extract the protocol version. */
115 protocol_version = (USHORT)(((USHORT)header_data[1] << 8) | header_data[2]);
116
117 /* Get the length of the TLS data. */
118 *length = (UINT)(((UINT)header_data[3] << 8) + header_data[4]);
119
120 /* Set header length. */
121 *header_length = NX_SECURE_TLS_RECORD_HEADER_SIZE;
122
123 /* Check the protocol version, except when we haven't established a version yet */
124 if (tls_session -> nx_secure_tls_protocol_version != 0)
125 {
126 /* Check the record's protocol version against the current session. */
127 status = _nx_secure_tls_check_protocol_version(tls_session, protocol_version, NX_SECURE_TLS);
128 return(status);
129 }
130
131 return(NX_SUCCESS);
132 }
133
134
