1 /*
2  * Copyright (c) 2013-2019 Huawei Technologies Co., Ltd. All rights reserved.
3  * Copyright (c) 2020-2021 Huawei Device Co., Ltd. All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without modification,
6  * are permitted provided that the following conditions are met:
7  *
8  * 1. Redistributions of source code must retain the above copyright notice, this list of
9  *    conditions and the following disclaimer.
10  *
11  * 2. Redistributions in binary form must reproduce the above copyright notice, this list
12  *    of conditions and the following disclaimer in the documentation and/or other materials
13  *    provided with the distribution.
14  *
15  * 3. Neither the name of the copyright holder nor the names of its contributors may be used
16  *    to endorse or promote products derived from this software without specific prior written
17  *    permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
21  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
23  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
24  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
25  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
26  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
27  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
28  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
29  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #include "trace_tlv.h"
33 #include "securec.h"
34 
35 #define CRC_WIDTH  8
36 #define CRC_POLY   0x1021
37 #define CRC_TOPBIT 0x8000
38 
CalcCrc16(const UINT8 *buf, UINT32 len)39 STATIC UINT16 CalcCrc16(const UINT8 *buf, UINT32 len)
40 {
41     UINT32 i;
42     UINT16 crc = 0;
43 
44     for (; len > 0; len--) {
45         crc = crc ^ (*buf++ << CRC_WIDTH);
46         for (i = 0; i < CRC_WIDTH; i++) {
47             if (crc & CRC_TOPBIT) {
48                 crc = (crc << 1) ^ CRC_POLY;
49             } else {
50                 crc <<= 1;
51             }
52         }
53     }
54     return crc;
55 }
56 
OsWriteTlv(UINT8 *tlvBuf, UINT8 type, UINT8 len, UINT8 *value)57 STATIC UINT32 OsWriteTlv(UINT8 *tlvBuf, UINT8 type, UINT8 len, UINT8 *value)
58 {
59     TraceMsgTlvBody *body = (TraceMsgTlvBody *)tlvBuf;
60 
61     if (len == 0) {
62         return 0;
63     }
64 
65     body->type = type;
66     body->len = len;
67     /* Do not check return value for performance, if copy failed, only this package will be discarded */
68     (VOID)memcpy_s(body->value, len, value, len);
69     return len + sizeof(body->type) + sizeof(body->len);
70 }
71 
OsTlvEncode(const TlvTable *table, UINT8 *srcBuf, UINT8 *tlvBuf, INT32 tlvBufLen)72 STATIC UINT32 OsTlvEncode(const TlvTable *table, UINT8 *srcBuf, UINT8 *tlvBuf, INT32 tlvBufLen)
73 {
74     UINT32 len = 0;
75     const TlvTable *tlvTableItem = table;
76 
77     while (tlvTableItem->tag != TRACE_TLV_TYPE_NULL) {
78         if ((len + tlvTableItem->elemSize + sizeof(UINT8) + sizeof(UINT8)) > tlvBufLen) {
79             break;
80         }
81         len += OsWriteTlv(tlvBuf + len, tlvTableItem->tag, tlvTableItem->elemSize, srcBuf + tlvTableItem->elemOffset);
82         tlvTableItem++;
83     }
84     return len;
85 }
86 
OsTraceDataEncode(UINT8 type, const TlvTable *table, UINT8 *src, UINT8 *dest, INT32 destLen)87 UINT32 OsTraceDataEncode(UINT8 type, const TlvTable *table, UINT8 *src, UINT8 *dest, INT32 destLen)
88 {
89     UINT16 crc;
90     INT32 len;
91     INT32 tlvBufLen;
92     UINT8 *tlvBuf = NULL;
93 
94     TraceMsgTlvHead *head = (TraceMsgTlvHead *)dest;
95     tlvBufLen = destLen - sizeof(TraceMsgTlvHead);
96 
97     if ((tlvBufLen <= 0) || (table == NULL)) {
98         return 0;
99     }
100 
101     tlvBuf = dest + sizeof(TraceMsgTlvHead);
102     len = OsTlvEncode(table, src, tlvBuf, tlvBufLen);
103     crc = CalcCrc16(tlvBuf, len);
104 
105     head->magicNum = TRACE_TLV_MSG_HEAD;
106     head->msgType  = type;
107     head->len      = len;
108     head->crc      = crc;
109     return len + sizeof(TraceMsgTlvHead);
110 }
111