1 /* 2 * Copyright (C) 2007 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 #ifndef _INIT_DEVICES_H 18 #define _INIT_DEVICES_H 19 20 #include <sys/stat.h> 21 #include <sys/types.h> 22 23 #include <algorithm> 24 #include <set> 25 #include <string> 26 #include <vector> 27 28 #include <android-base/file.h> 29 #include <selinux/label.h> 30 31 #include "uevent.h" 32 #include "uevent_handler.h" 33 34 namespace android { 35 namespace init { 36 37 class Permissions { 38 public: 39 friend void TestPermissions(const Permissions& expected, const Permissions& test); 40 41 Permissions(const std::string& name, mode_t perm, uid_t uid, gid_t gid, bool no_fnm_pathname); 42 43 bool Match(const std::string& path) const; 44 perm()45 mode_t perm() const { return perm_; } uid()46 uid_t uid() const { return uid_; } gid()47 gid_t gid() const { return gid_; } 48 49 protected: name()50 const std::string& name() const { return name_; } 51 52 private: 53 std::string name_; 54 mode_t perm_; 55 uid_t uid_; 56 gid_t gid_; 57 bool prefix_; 58 bool wildcard_; 59 bool no_fnm_pathname_; 60 }; 61 62 class SysfsPermissions : public Permissions { 63 public: 64 friend void TestSysfsPermissions(const SysfsPermissions& expected, const SysfsPermissions& test); 65 SysfsPermissions(const std::string & name,const std::string & attribute,mode_t perm,uid_t uid,gid_t gid,bool no_fnm_pathname)66 SysfsPermissions(const std::string& name, const std::string& attribute, mode_t perm, uid_t uid, 67 gid_t gid, bool no_fnm_pathname) 68 : Permissions(name, perm, uid, gid, no_fnm_pathname), attribute_(attribute) {} 69 70 bool MatchWithSubsystem(const std::string& path, const std::string& subsystem) const; 71 void SetPermissions(const std::string& path) const; 72 73 private: 74 const std::string attribute_; 75 }; 76 77 class Subsystem { 78 public: 79 friend class SubsystemParser; 80 friend void TestSubsystems(const Subsystem& expected, const Subsystem& test); 81 82 enum DevnameSource { 83 DEVNAME_UEVENT_DEVNAME, 84 DEVNAME_UEVENT_DEVPATH, 85 DEVNAME_SYS_NAME, 86 }; 87 Subsystem()88 Subsystem() {} Subsystem(std::string name)89 Subsystem(std::string name) : name_(std::move(name)) {} Subsystem(std::string name,DevnameSource source,std::string dir_name)90 Subsystem(std::string name, DevnameSource source, std::string dir_name) 91 : name_(std::move(name)), devname_source_(source), dir_name_(std::move(dir_name)) {} 92 93 // Returns the full path for a uevent of a device that is a member of this subsystem, 94 // according to the rules parsed from ueventd.rc ParseDevPath(const Uevent & uevent)95 std::string ParseDevPath(const Uevent& uevent) const { 96 std::string devname; 97 if (devname_source_ == DEVNAME_UEVENT_DEVNAME) { 98 devname = uevent.device_name; 99 } else if (devname_source_ == DEVNAME_UEVENT_DEVPATH) { 100 devname = android::base::Basename(uevent.path); 101 } else if (devname_source_ == DEVNAME_SYS_NAME) { 102 if (android::base::ReadFileToString("/sys/" + uevent.path + "/name", &devname)) { 103 devname.pop_back(); // Remove terminating newline 104 } else { 105 devname = uevent.device_name; 106 } 107 } 108 return dir_name_ + "/" + devname; 109 } 110 111 bool operator==(const std::string& string_name) const { return name_ == string_name; } 112 113 private: 114 std::string name_; 115 DevnameSource devname_source_ = DEVNAME_UEVENT_DEVNAME; 116 std::string dir_name_ = "/dev"; 117 }; 118 119 class DeviceHandler : public UeventHandler { 120 public: 121 friend class DeviceHandlerTester; 122 123 DeviceHandler(); 124 DeviceHandler(std::vector<Permissions> dev_permissions, 125 std::vector<SysfsPermissions> sysfs_permissions, std::vector<Subsystem> subsystems, 126 std::set<std::string> boot_devices, bool skip_restorecon); 127 virtual ~DeviceHandler() = default; 128 129 void HandleUevent(const Uevent& uevent) override; 130 131 // `androidboot.partition_map` allows associating a partition name for a raw block device 132 // through a comma separated and semicolon deliminated list. For example, 133 // `androidboot.partition_map=vdb,metadata;vdc,userdata` maps `vdb` to `metadata` and `vdc` to 134 // `userdata`. 135 static std::string GetPartitionNameForDevice(const std::string& device); 136 137 private: 138 void ColdbootDone() override; 139 bool FindPlatformDevice(std::string path, std::string* platform_device_path) const; 140 std::tuple<mode_t, uid_t, gid_t> GetDevicePermissions( 141 const std::string& path, const std::vector<std::string>& links) const; 142 void MakeDevice(const std::string& path, bool block, int major, int minor, 143 const std::vector<std::string>& links) const; 144 std::vector<std::string> GetBlockDeviceSymlinks(const Uevent& uevent) const; 145 void HandleDevice(const std::string& action, const std::string& devpath, bool block, int major, 146 int minor, const std::vector<std::string>& links) const; 147 void FixupSysPermissions(const std::string& upath, const std::string& subsystem) const; 148 void HandleAshmemUevent(const Uevent& uevent); 149 150 std::vector<Permissions> dev_permissions_; 151 std::vector<SysfsPermissions> sysfs_permissions_; 152 std::vector<Subsystem> subsystems_; 153 std::set<std::string> boot_devices_; 154 bool skip_restorecon_; 155 std::string sysfs_mount_point_; 156 }; 157 158 // Exposed for testing 159 void SanitizePartitionName(std::string* string); 160 161 } // namespace init 162 } // namespace android 163 164 #endif 165