1 /*
2  * Copyright (c) 2022 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 #include <ctype.h>
16 #include <limits.h>
17 
18 #include "param_manager.h"
19 #include "param_trie.h"
20 #include "param_base.h"
21 
GetWorkSpaceByName(const char * name)22 INIT_LOCAL_API WorkSpace *GetWorkSpaceByName(const char *name)
23 {
24     ParamWorkSpace *paramSpace = GetParamWorkSpace();
25     PARAM_CHECK(paramSpace != NULL, return NULL, "Invalid paramSpace");
26 #ifdef PARAM_SUPPORT_SELINUX
27     if (paramSpace->selinuxSpace.getParamLabelIndex == NULL) {
28         return NULL;
29     }
30     uint32_t labelIndex = (uint32_t)paramSpace->selinuxSpace.getParamLabelIndex(name) + WORKSPACE_INDEX_BASE;
31     if (labelIndex < paramSpace->maxSpaceCount) {
32         return paramSpace->workSpace[labelIndex];
33     }
34     return NULL;
35 #else
36     return paramSpace->workSpace[WORKSPACE_INDEX_DAC];
37 #endif
38 }
39 
GetWorkSpace(uint32_t labelIndex)40 INIT_LOCAL_API WorkSpace *GetWorkSpace(uint32_t labelIndex)
41 {
42     ParamWorkSpace *paramSpace = GetParamWorkSpace();
43     PARAM_CHECK(paramSpace != NULL, return NULL, "Invalid paramSpace");
44     PARAM_CHECK(paramSpace->workSpace != NULL, return NULL, "Invalid paramSpace->workSpace");
45     PARAM_WORKSPACE_CHECK(paramSpace, return NULL, "Invalid space");
46 #ifdef PARAM_SUPPORT_SELINUX
47     if (labelIndex == 0) {
48         return paramSpace->workSpace[0];
49     }
50     WorkSpace *workSpace = NULL;
51     if (labelIndex < paramSpace->maxSpaceCount) {
52         workSpace = paramSpace->workSpace[labelIndex];
53     }
54     if (workSpace == NULL) {
55         return NULL;
56     }
57     uint32_t rwSpaceLock = ATOMIC_LOAD_EXPLICIT(&workSpace->rwSpaceLock, MEMORY_ORDER_ACQUIRE);
58     if (rwSpaceLock & WORKSPACE_STATUS_IN_PROCESS) {
59         return NULL;
60     }
61     if (workSpace->area != NULL) {
62         return workSpace;
63     }
64     return NULL;
65 #else
66     return paramSpace->workSpace[0];
67 #endif
68 }
69 
GetParamSecurityOps(int type)70 INIT_LOCAL_API ParamSecurityOps *GetParamSecurityOps(int type)
71 {
72     PARAM_CHECK(type < PARAM_SECURITY_MAX, return NULL, "Invalid type");
73     ParamWorkSpace *paramSpace = GetParamWorkSpace();
74     PARAM_CHECK(paramSpace != NULL, return NULL, "Invalid paramSpace");
75     return &paramSpace->paramSecurityOps[type];
76 }
77 
GetParamSecurityLabel()78 INIT_LOCAL_API ParamSecurityLabel *GetParamSecurityLabel()
79 {
80     ParamWorkSpace *paramSpace = GetParamWorkSpace();
81     PARAM_CHECK(paramSpace != NULL, return NULL, "Invalid paramSpace");
82     return &paramSpace->securityLabel;
83 }
84 
SplitParamString(char * line,const char * exclude[],uint32_t count,int (* result)(const uint32_t * context,const char * name,const char * value),const uint32_t * context)85 INIT_LOCAL_API int SplitParamString(char *line, const char *exclude[], uint32_t count,
86     int (*result)(const uint32_t *context, const char *name, const char *value), const uint32_t *context)
87 {
88     PARAM_CHECK(line != NULL, return 0, "Empty line");
89     // Skip spaces
90     char *name = line;
91     while (isspace(*name) && (*name != '\0')) {
92         name++;
93     }
94     // Empty line or Comment line
95     if (*name == '\0' || *name == '#') {
96         return 0;
97     }
98 
99     char *value = name;
100     // find the first delimiter '='
101     while (*value != '\0') {
102         if (*value == '=') {
103             (*value) = '\0';
104             value = value + 1;
105             break;
106         }
107         value++;
108     }
109 
110     // Skip spaces
111     char *tmp = name;
112     while ((tmp < value) && (*tmp != '\0')) {
113         if (isspace(*tmp)) {
114             (*tmp) = '\0';
115             break;
116         }
117         tmp++;
118     }
119 
120     // empty name, just ignore this line
121     if (*value == '\0') {
122         return 0;
123     }
124 
125     // Filter excluded parameters
126     for (uint32_t i = 0; i < count; i++) {
127         if (strncmp(name, exclude[i], strlen(exclude[i])) == 0) {
128             return 0;
129         }
130     }
131 
132     // Skip spaces for value
133     while (isspace(*value) && (*value != '\0')) {
134         value++;
135     }
136 
137     // Trim the ending spaces of value
138     char *pos = value + strlen(value);
139     pos--;
140     while (isspace(*pos) && pos > value) {
141         (*pos) = '\0';
142         pos--;
143     }
144 
145     // Strip starting and ending " for value
146     if ((*value == '"') && (pos > value) && (*pos == '"')) {
147         value = value + 1;
148         *pos = '\0';
149     }
150     return result(context, name, value);
151 }
152