1 /*
2  *  Copyright 2014 Google, Inc
3  *
4  *  Licensed under the Apache License, Version 2.0 (the "License");
5  *  you may not use this file except in compliance with the License.
6  *  You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  *  Unless required by applicable law or agreed to in writing, software
11  *  distributed under the License is distributed on an "AS IS" BASIS,
12  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  *  See the License for the specific language governing permissions and
14  *  limitations under the License.
15  */
16 
17 #pragma once
18 
19 #include <sys/cdefs.h>
20 #include <sys/types.h>
21 #include <initializer_list>
22 #include <span>
23 #include <string>
24 #include <string_view>
25 #include <vector>
26 
27 __BEGIN_DECLS
28 
29 static constexpr const char* CGROUPV2_HIERARCHY_NAME = "cgroup2";
30 [[deprecated]] static constexpr const char* CGROUPV2_CONTROLLER_NAME = "cgroup2";
31 
32 bool CgroupsAvailable();
33 bool CgroupGetControllerPath(const std::string& cgroup_name, std::string* path);
34 bool CgroupGetControllerFromPath(const std::string& path, std::string* cgroup_name);
35 bool CgroupGetAttributePath(const std::string& attr_name, std::string* path);
36 bool CgroupGetAttributePathForTask(const std::string& attr_name, pid_t tid, std::string* path);
37 
38 bool SetTaskProfiles(pid_t tid, const std::vector<std::string>& profiles,
39                      bool use_fd_cache = false);
40 bool SetProcessProfiles(uid_t uid, pid_t pid, const std::vector<std::string>& profiles);
41 bool SetUserProfiles(uid_t uid, const std::vector<std::string>& profiles);
42 
43 __END_DECLS
44 
45 bool SetTaskProfiles(pid_t tid, std::initializer_list<std::string_view> profiles,
46                      bool use_fd_cache = false);
47 bool SetProcessProfiles(uid_t uid, pid_t pid, std::initializer_list<std::string_view> profiles);
48 #if _LIBCPP_STD_VER > 17
49 bool SetTaskProfiles(pid_t tid, std::span<const std::string_view> profiles,
50                      bool use_fd_cache = false);
51 bool SetProcessProfiles(uid_t uid, pid_t pid, std::span<const std::string_view> profiles);
52 #endif
53 
54 __BEGIN_DECLS
55 
56 #ifndef __ANDROID_VNDK__
57 
58 bool SetProcessProfilesCached(uid_t uid, pid_t pid, const std::vector<std::string>& profiles);
59 
60 static constexpr const char* CGROUPS_RC_PATH = "/dev/cgroup_info/cgroup.rc";
61 
62 bool UsePerAppMemcg();
63 
64 // Drop the fd cache of cgroup path. It is used for when resource caching is enabled and a process
65 // loses the access to the path, the access checking (See SetCgroupAction::EnableResourceCaching)
66 // should be active again. E.g. Zygote specialization for child process.
67 void DropTaskProfilesResourceCaching();
68 
69 // Return 0 if all processes were killed and the cgroup was successfully removed.
70 // Returns -1 in the case of an error occurring or if there are processes still running.
71 int killProcessGroup(uid_t uid, pid_t initialPid, int signal);
72 
73 // Returns the same as killProcessGroup(), however it does not retry, which means
74 // that it only returns 0 in the case that the cgroup exists and it contains no processes.
75 int killProcessGroupOnce(uid_t uid, pid_t initialPid, int signal);
76 
77 // Sends the provided signal to all members of a process group, but does not wait for processes to
78 // exit, or for the cgroup to be removed. Callers should also ensure that killProcessGroup is called
79 // later to ensure the cgroup is fully removed, otherwise system resources will leak.
80 // Returns true if no errors are encountered sending signals, otherwise false.
81 bool sendSignalToProcessGroup(uid_t uid, pid_t initialPid, int signal);
82 
83 int createProcessGroup(uid_t uid, pid_t initialPid, bool memControl = false);
84 
85 // Set various properties of a process group. For these functions to work, the process group must
86 // have been created by passing memControl=true to createProcessGroup.
87 bool setProcessGroupSwappiness(uid_t uid, pid_t initialPid, int swappiness);
88 bool setProcessGroupSoftLimit(uid_t uid, pid_t initialPid, int64_t softLimitInBytes);
89 bool setProcessGroupLimit(uid_t uid, pid_t initialPid, int64_t limitInBytes);
90 
91 void removeAllEmptyProcessGroups(void);
92 
93 // Provides the path for an attribute in a specific process group
94 // Returns false in case of error, true in case of success
95 bool getAttributePathForTask(const std::string& attr_name, pid_t tid, std::string* path);
96 
97 // Check if a profile can be applied without failing.
98 // Returns true if it can be applied without failing, false otherwise
99 bool isProfileValidForProcess(const std::string& profile_name, uid_t uid, pid_t pid);
100 
101 #endif // __ANDROID_VNDK__
102 
103 __END_DECLS
104