1 /*
2 * Copyright (c) 2021 Huawei Device Co., Ltd.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at
6 *
7 * http://www.apache.org/licenses/LICENSE-2.0
8 *
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
14 */
15
16 #include "securecutil.h"
17
SecDoWcscat(wchar_t * strDest,size_t destMax,const wchar_t * strSrc)18 static errno_t SecDoWcscat(wchar_t *strDest, size_t destMax, const wchar_t *strSrc)
19 {
20 wchar_t *tmpDest = strDest;
21 const wchar_t *tmpSrc = strSrc;
22 size_t availableSize = destMax;
23 SECUREC_IN_REGISTER const wchar_t *overlapGuard = NULL;
24
25 if (tmpDest < tmpSrc) {
26 overlapGuard = tmpSrc;
27 while (availableSize > 0 && *tmpDest != '\0') {
28 if (tmpDest == overlapGuard) {
29 strDest[0] = '\0';
30 SECUREC_ERROR_BUFFER_OVERLAP("wcscat_s");
31 return EOVERLAP_AND_RESET;
32 }
33 /* seek to string end */
34 ++tmpDest;
35 --availableSize;
36 }
37
38 /* strDest unterminated, return error. */
39 if (availableSize == 0) {
40 strDest[0] = '\0';
41 SECUREC_ERROR_INVALID_PARAMTER("wcscat_s");
42 return EINVAL_AND_RESET;
43 }
44
45 /* if 2014-2018 > 0, then execute the strcat operation */
46 while ((*tmpDest++ = *tmpSrc++) != '\0' && --availableSize > 0) {
47 if (tmpDest == overlapGuard) {
48 strDest[0] = '\0';
49 SECUREC_ERROR_BUFFER_OVERLAP("wcscat_s");
50 return EOVERLAP_AND_RESET;
51 }
52 }
53 } else {
54 overlapGuard = tmpDest;
55 while (availableSize > 0 && *tmpDest != '\0') {
56 /* seek to string end, and no need to check overlap */
57 ++tmpDest;
58 --availableSize;
59 }
60 /* strDest unterminated, return error. */
61 if (availableSize == 0) {
62 strDest[0] = '\0';
63 SECUREC_ERROR_INVALID_PARAMTER("wcscat_s");
64 return EINVAL_AND_RESET;
65 }
66 while ((*tmpDest++ = *tmpSrc++) != '\0' && --availableSize > 0) {
67 if (tmpSrc == overlapGuard) {
68 strDest[0] = '\0';
69 SECUREC_ERROR_BUFFER_OVERLAP("wcscat_s");
70 return EOVERLAP_AND_RESET;
71 }
72 }
73 }
74
75 /* strDest have not enough space, return error */
76 if (availableSize == 0) {
77 strDest[0] = '\0';
78 SECUREC_ERROR_INVALID_RANGE("wcscat_s");
79 return ERANGE_AND_RESET;
80 }
81 return EOK;
82 }
83
84 /*******************************************************************************
85 * <FUNCTION DESCRIPTION>
86 * The wcscat_s function appends a copy of the wide string pointed to by strSrc
87 * (including the terminating null wide character)
88 * to the end of the wide string pointed to by strDest.
89 * The arguments and return value of wcscat_s are wide-character strings.
90 *
91 * The wcscat_s function appends strSrc to strDest and terminates the resulting
92 * string with a null character. The initial character of strSrc overwrites the
93 * terminating null character of strDest. wcscat_s will return EOVERLAP_AND_RESET if the
94 * source and destination strings overlap.
95 *
96 * Note that the second parameter is the total size of the buffer, not the
97 * remaining size.
98 *
99 * <INPUT PARAMETERS>
100 * strDest Null-terminated destination string buffer.
101 * destMax Size of the destination string buffer.
102 * strSrc Null-terminated source string buffer.
103 *
104 * <OUTPUT PARAMETERS>
105 * strDest is updated
106 *
107 * <RETURN VALUE>
108 * EOK Success
109 * EINVAL strDest is NULL and destMax != 0 and destMax <= SECUREC_WCHAR_STRING_MAX_LEN
110 * EINVAL_AND_RESET (strDest unterminated and all other parameters are valid) or
111 * (strDest != NULL and strSrc is NULL and destMax != 0
112 * and destMax <= SECUREC_WCHAR_STRING_MAX_LEN)
113 * ERANGE destMax > SECUREC_WCHAR_STRING_MAX_LEN or destMax is 0
114 * ERANGE_AND_RESET strDest have not enough space and all other parameters are valid and not overlap
115 * EOVERLAP_AND_RESET dest buffer and source buffer are overlapped and all parameters are valid
116 *
117 * If there is a runtime-constraint violation, strDest[0] will be set to the '\0' when strDest and destMax valid
118 *******************************************************************************
119 */
wcscat_s(wchar_t * strDest,size_t destMax,const wchar_t * strSrc)120 errno_t wcscat_s(wchar_t *strDest, size_t destMax, const wchar_t *strSrc)
121 {
122 if (destMax == 0 || destMax > SECUREC_WCHAR_STRING_MAX_LEN) {
123 SECUREC_ERROR_INVALID_RANGE("wcscat_s");
124 return ERANGE;
125 }
126
127 if (strDest == NULL || strSrc == NULL) {
128 SECUREC_ERROR_INVALID_PARAMTER("wcscat_s");
129 if (strDest != NULL) {
130 strDest[0] = '\0';
131 return EINVAL_AND_RESET;
132 }
133 return EINVAL;
134 }
135
136 return SecDoWcscat(strDest, destMax, strSrc);
137 }
138
139
140