1 /* 2 * Copyright (C) 2017 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 #include "ueventd_parser.h" 18 19 #include <grp.h> 20 #include <pwd.h> 21 22 #include "keyword_map.h" 23 24 namespace android { 25 namespace init { 26 27 Result<Success> ParsePermissionsLine(std::vector<std::string>&& args, 28 std::vector<SysfsPermissions>* out_sysfs_permissions, 29 std::vector<Permissions>* out_dev_permissions) { 30 bool is_sysfs = out_sysfs_permissions != nullptr; 31 if (is_sysfs && args.size() != 5) { 32 return Error() << "/sys/ lines must have 5 entries"; 33 } 34 35 if (!is_sysfs && args.size() != 4) { 36 return Error() << "/dev/ lines must have 4 entries"; 37 } 38 39 auto it = args.begin(); 40 const std::string& name = *it++; 41 42 std::string sysfs_attribute; 43 if (is_sysfs) sysfs_attribute = *it++; 44 45 // args is now common to both sys and dev entries and contains: <perm> <uid> <gid> 46 std::string& perm_string = *it++; 47 char* end_pointer = 0; 48 mode_t perm = strtol(perm_string.c_str(), &end_pointer, 8); 49 if (end_pointer == nullptr || *end_pointer != '\0') { 50 return Error() << "invalid mode '" << perm_string << "'"; 51 } 52 53 std::string& uid_string = *it++; 54 passwd* pwd = getpwnam(uid_string.c_str()); 55 if (!pwd) { 56 return Error() << "invalid uid '" << uid_string << "'"; 57 } 58 uid_t uid = pwd->pw_uid; 59 60 std::string& gid_string = *it++; 61 struct group* grp = getgrnam(gid_string.c_str()); 62 if (!grp) { 63 return Error() << "invalid gid '" << gid_string << "'"; 64 } 65 gid_t gid = grp->gr_gid; 66 67 if (is_sysfs) { 68 out_sysfs_permissions->emplace_back(name, sysfs_attribute, perm, uid, gid); 69 } else { 70 out_dev_permissions->emplace_back(name, perm, uid, gid); 71 } 72 return Success(); 73 } 74 75 Result<Success> SubsystemParser::ParseSection(std::vector<std::string>&& args, 76 const std::string& filename, int line) { 77 if (args.size() != 2) { 78 return Error() << "subsystems must have exactly one name"; 79 } 80 81 if (std::find(subsystems_->begin(), subsystems_->end(), args[1]) != subsystems_->end()) { 82 return Error() << "ignoring duplicate subsystem entry"; 83 } 84 85 subsystem_ = Subsystem(std::move(args[1])); 86 87 return Success(); 88 } 89 90 Result<Success> SubsystemParser::ParseDevName(std::vector<std::string>&& args) { 91 if (args[1] == "uevent_devname") { 92 subsystem_.devname_source_ = Subsystem::DevnameSource::DEVNAME_UEVENT_DEVNAME; 93 return Success(); 94 } 95 if (args[1] == "uevent_devpath") { 96 subsystem_.devname_source_ = Subsystem::DevnameSource::DEVNAME_UEVENT_DEVPATH; 97 return Success(); 98 } 99 100 return Error() << "invalid devname '" << args[1] << "'"; 101 } 102 103 Result<Success> SubsystemParser::ParseDirName(std::vector<std::string>&& args) { 104 if (args[1].front() != '/') { 105 return Error() << "dirname '" << args[1] << " ' does not start with '/'"; 106 } 107 108 subsystem_.dir_name_ = args[1]; 109 return Success(); 110 } 111 112 Result<Success> SubsystemParser::ParseLineSection(std::vector<std::string>&& args, int line) { 113 using OptionParser = Result<Success> (SubsystemParser::*)(std::vector<std::string> && args); 114 115 static class OptionParserMap : public KeywordMap<OptionParser> { 116 private: 117 const Map& map() const override { 118 // clang-format off 119 static const Map option_parsers = { 120 {"devname", {1, 1, &SubsystemParser::ParseDevName}}, 121 {"dirname", {1, 1, &SubsystemParser::ParseDirName}}, 122 }; 123 // clang-format on 124 return option_parsers; 125 } 126 } parser_map; 127 128 auto parser = parser_map.FindFunction(args); 129 130 if (!parser) return Error() << parser.error(); 131 132 return std::invoke(*parser, this, std::move(args)); 133 } 134 135 Result<Success> SubsystemParser::EndSection() { 136 subsystems_->emplace_back(std::move(subsystem_)); 137 138 return Success(); 139 } 140 141 } // namespace init 142 } // namespace android 143