1 /*
2 * Copyright (c) 2021-2022 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
16 #include <errno.h>
17 #include <sys/prctl.h>
18 #include <sys/stat.h>
19 #include <sys/types.h>
20 #include <unistd.h>
21
22 #ifdef __LINUX__
23 #include <linux/capability.h>
24 #include <linux/securebits.h>
25 #include <sys/resource.h>
26 #include <sys/time.h>
27 #else
28 #include <sys/capability.h>
29 #endif // __LINUX__
30
31 #include "ability_main.h"
32 #include "appspawn_message.h"
33 #include "appspawn_server.h"
34 #include "appspawn_service.h"
35 #include "securec.h"
36
37 #define DEFAULT_UMASK 002
38 #define CAP_NUM 2
39 #define ENV_TITLE "LD_LIBRARY_PATH="
40 #define UPPER_BOUND_GID 999
41 #define LOWER_BOUND_GID 100
42 #define GRP_NUM 2
43 #define DEVMGR_GRP 99
44
SetAmbientCapability(int cap)45 static int SetAmbientCapability(int cap)
46 {
47 #ifdef __LINUX__
48 if (prctl(PR_CAP_AMBIENT, PR_CAP_AMBIENT_RAISE, cap, 0, 0)) {
49 printf("[Init] prctl PR_CAP_AMBIENT failed\n");
50 return -1;
51 }
52 #endif
53 return 0;
54 }
55
SetCapability(unsigned int capsCnt,const unsigned int * caps)56 static int SetCapability(unsigned int capsCnt, const unsigned int *caps)
57 {
58 struct __user_cap_header_struct capHeader;
59 capHeader.version = _LINUX_CAPABILITY_VERSION_3;
60 capHeader.pid = 0;
61
62 // common user, clear all caps
63 struct __user_cap_data_struct capData[CAP_NUM] = {0};
64 for (unsigned int i = 0; i < capsCnt; ++i) {
65 capData[CAP_TO_INDEX(caps[i])].effective |= CAP_TO_MASK(caps[i]);
66 capData[CAP_TO_INDEX(caps[i])].permitted |= CAP_TO_MASK(caps[i]);
67 capData[CAP_TO_INDEX(caps[i])].inheritable |= CAP_TO_MASK(caps[i]);
68 }
69
70 if (capset(&capHeader, capData) != 0) {
71 APPSPAWN_LOGE("[appspawn] capset failed, err: %d.", errno);
72 return -1;
73 }
74 for (unsigned int i = 0; i < capsCnt; ++i) {
75 if (SetAmbientCapability(caps[i]) != 0) {
76 APPSPAWN_LOGE("[appspawn] SetAmbientCapability failed, err: %d.", errno);
77 return -1;
78 }
79 }
80 return 0;
81 }
82
SetProcessName(struct AppSpawnContent_ * content,AppSpawnClient * client,char * longProcName,uint32_t longProcNameLen)83 static int SetProcessName(struct AppSpawnContent_ *content, AppSpawnClient *client,
84 char *longProcName, uint32_t longProcNameLen)
85 {
86 AppSpawnClientLite *appProperty = (AppSpawnClientLite *)client;
87 return prctl(PR_SET_NAME, appProperty->message.bundleName);
88 }
89
SetKeepCapabilities(struct AppSpawnContent_ * content,AppSpawnClient * client)90 static int SetKeepCapabilities(struct AppSpawnContent_ *content, AppSpawnClient *client)
91 {
92 APPSPAWN_LOGE("SetKeepCapabilities");
93 #ifdef __LINUX__
94 if (prctl(PR_SET_SECUREBITS, SECBIT_NO_SETUID_FIXUP | SECBIT_NO_SETUID_FIXUP_LOCKED)) {
95 printf("prctl failed\n");
96 return -1;
97 }
98 #endif
99 return 0;
100 }
101
SetUidGid(struct AppSpawnContent_ * content,AppSpawnClient * client)102 static int SetUidGid(struct AppSpawnContent_ *content, AppSpawnClient *client)
103 {
104 AppSpawnClientLite *appProperty = (AppSpawnClientLite *)client;
105 APPSPAWN_LOGE("SetUidGid %d %d", appProperty->message.uID, appProperty->message.gID);
106 if (setgid(appProperty->message.gID) != 0) {
107 APPSPAWN_LOGE("[appspawn] setgid failed, gID %u, err: %d.", appProperty->message.gID, errno);
108 return -1;
109 }
110
111 if (setuid(appProperty->message.uID) != 0) {
112 APPSPAWN_LOGE("[appspawn] setuid failed, uID %u, err: %d.", appProperty->message.uID, errno);
113 return -1;
114 }
115 gid_t groups[GRP_NUM];
116 // add device groups for system app
117 if (appProperty->message.gID >= LOWER_BOUND_GID && appProperty->message.gID <= UPPER_BOUND_GID) {
118 groups[0] = appProperty->message.gID;
119 groups[1] = DEVMGR_GRP;
120 if (setgroups(GRP_NUM, groups)) {
121 APPSPAWN_LOGE("[appspawn] setgroups failed, uID %u, err: %d.", appProperty->message.uID, errno);
122 return -1;
123 }
124 }
125
126 // umask call always succeeds and return the previous mask value which is not needed here
127 (void)umask(DEFAULT_UMASK);
128 return 0;
129 }
130
SetCapabilities(struct AppSpawnContent_ * content,AppSpawnClient * client)131 static int SetCapabilities(struct AppSpawnContent_ *content, AppSpawnClient *client)
132 {
133 AppSpawnClientLite *appProperty = (AppSpawnClientLite *)client;
134 APPSPAWN_LOGE("SetCapabilities appProperty->message.capsCnt %d", appProperty->message.capsCnt);
135 // set rlimit
136 #ifdef __LINUX__
137 static const rlim_t DEFAULT_RLIMIT = 40;
138 struct rlimit rlim = {0};
139 rlim.rlim_cur = DEFAULT_RLIMIT;
140 rlim.rlim_max = DEFAULT_RLIMIT;
141 if (setrlimit(RLIMIT_NICE, &rlim) != 0) {
142 APPSPAWN_LOGE("[appspawn] setrlimit failed, err: %d.", errno);
143 return -1;
144 }
145
146 #ifndef APPSPAWN_TEST
147 unsigned int tmpCaps[] = {17}; // 17 means CAP_SYS_RAWIO
148 unsigned int tmpsCapCnt = sizeof(tmpCaps) / sizeof(tmpCaps[0]);
149 if (SetCapability(tmpsCapCnt, tmpCaps) != 0) {
150 APPSPAWN_LOGE("[appspawn] setrlimit failed, err: %d.", errno);
151 return -1;
152 }
153 #endif
154 #else
155 if (SetCapability(appProperty->message.capsCnt, appProperty->message.caps) != 0) {
156 APPSPAWN_LOGE("[appspawn] SetCapability failed, err: %d.", errno);
157 return -1;
158 }
159 #endif // __LINUX__
160 APPSPAWN_LOGE("SetCapabilities appProperty->message.capsCnt %d", appProperty->message.capsCnt);
161 return 0;
162 }
163
RunChildProcessor(AppSpawnContent * content,AppSpawnClient * client)164 static void RunChildProcessor(AppSpawnContent *content, AppSpawnClient *client)
165 {
166 APPSPAWN_LOGI("AbilityMain");
167 AppSpawnClientLite *appProperty = (AppSpawnClientLite *)client;
168 APPSPAWN_LOGI("[appspawn] invoke, msg<%s,%s,%d,%d>",
169 appProperty->message.bundleName, appProperty->message.identityID, appProperty->message.uID,
170 appProperty->message.gID);
171
172 #ifndef APPSPAWN_TEST
173 if (AbilityMain(appProperty->message.identityID) != 0) {
174 APPSPAWN_LOGE("[appspawn] AbilityMain execute failed, pid %d.", getpid());
175 exit(0x7f); // 0x7f: user specified
176 }
177 #endif
178 }
179
SetContentFunction(AppSpawnContent * content)180 void SetContentFunction(AppSpawnContent *content)
181 {
182 APPSPAWN_LOGI("SetContentFunction");
183 content->setProcessName = SetProcessName;
184 content->setKeepCapabilities = SetKeepCapabilities;
185 content->setUidGid = SetUidGid;
186 content->setCapabilities = SetCapabilities;
187 content->runChildProcessor = RunChildProcessor;
188
189 content->setFileDescriptors = NULL;
190 content->setAppSandbox = NULL;
191 content->setAppAccessToken = NULL;
192 content->notifyResToParent = NULL;
193 content->loadExtendLib = NULL;
194 content->initAppSpawn = NULL;
195 content->runAppSpawn = NULL;
196 content->clearEnvironment = NULL;
197 }
198