1 /*
2 * Copyright (C) 2019 The Android Open Source Project
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/resource.h>
20 #include <sys/types.h>
21
22 #include <optional>
23 #include <string>
24 #include <vector>
25
26 #include <android-base/unique_fd.h>
27 #include <cutils/iosched_policy.h>
28
29 #include "interprocess_fifo.h"
30 #include "mount_namespace.h"
31 #include "result.h"
32
33 namespace android {
34 namespace init {
35
36 // Constants used by Service::Start() for communication between parent and child.
37 enum ServiceCode : uint8_t {
38 kActivatingCgroupsFailed,
39 kCgroupsActivated,
40 kSetSidFinished,
41 };
42
43 class Descriptor {
44 public:
Descriptor(const std::string & name,android::base::unique_fd fd)45 Descriptor(const std::string& name, android::base::unique_fd fd)
46 : name_(name), fd_(std::move(fd)){};
47
48 // Publish() unsets FD_CLOEXEC from the FD and publishes its name via setenv(). It should be
49 // called when starting a service after fork() and before exec().
50 void Publish() const;
51
52 private:
53 std::string name_;
54 android::base::unique_fd fd_;
55 };
56
57 struct SocketDescriptor {
58 std::string name;
59 int type = 0;
60 uid_t uid = 0;
61 gid_t gid = 0;
62 int perm = 0;
63 std::string context;
64 bool passcred = false;
65 bool listen = false;
66 bool persist = false;
67
68 // Create() creates the named unix domain socket in /dev/socket and returns a Descriptor object.
69 // It should be called when starting a service, before calling fork(), such that the socket is
70 // synchronously created before starting any other services, which may depend on it.
71 Result<Descriptor> Create(const std::string& global_context) const;
72 };
73
74 struct FileDescriptor {
75 std::string name;
76 std::string type;
77
78 Result<Descriptor> Create() const;
79 };
80
81 struct NamespaceInfo {
82 int flags;
83 // Pair of namespace type, path to name.
84 std::vector<std::pair<int, std::string>> namespaces_to_enter;
85 };
86 Result<void> EnterNamespaces(const NamespaceInfo& info, const std::string& name,
87 std::optional<MountNamespace> override_mount_namespace);
88
89 struct ProcessAttributes {
90 std::string console;
91 IoSchedClass ioprio_class;
92 int ioprio_pri;
93 std::vector<std::pair<int, rlimit>> rlimits;
94 uid_t uid;
95 gid_t gid;
96 std::vector<gid_t> supp_gids;
97 int priority;
98 bool stdio_to_kmsg;
99 };
100
RequiresConsole(const ProcessAttributes & attr)101 inline bool RequiresConsole(const ProcessAttributes& attr) {
102 return !attr.console.empty();
103 }
104
105 Result<void> SetProcessAttributes(const ProcessAttributes& attr, InterprocessFifo setsid_finished);
106
107 Result<void> WritePidToFiles(std::vector<std::string>* files);
108
109 } // namespace init
110 } // namespace android
111