1 /* 2 * Copyright (C) 2018 The Android Open Source Project 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in 12 * the documentation and/or other materials provided with the 13 * distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #pragma once 30 31 #include <grp.h> 32 #include <pwd.h> 33 34 #include "private/bionic_lock.h" 35 #include "private/bionic_macros.h" 36 #include "private/grp_pwd.h" 37 38 class MmapFile { 39 public: 40 MmapFile(const char* filename, const char* required_prefix); 41 42 template <typename Line> 43 bool FindById(uid_t uid, Line* line); 44 template <typename Line> 45 bool FindByName(const char* name, Line* line); 46 void Unmap(); 47 48 BIONIC_DISALLOW_IMPLICIT_CONSTRUCTORS(MmapFile); 49 50 private: 51 enum class FileStatus { 52 Uninitialized, 53 Initialized, 54 Error, 55 }; 56 57 bool GetFile(const char** start, const char** end); 58 bool DoMmap(); 59 60 template <typename Line, typename Predicate> 61 bool Find(Line* line, Predicate predicate); 62 63 FileStatus status_ = FileStatus::Uninitialized; 64 Lock lock_; 65 const char* filename_ = nullptr; 66 const char* start_ = nullptr; 67 const char* end_ = nullptr; 68 const char* required_prefix_; 69 }; 70 71 class PasswdFile { 72 public: 73 PasswdFile(const char* filename, const char* required_prefix); 74 75 bool FindById(uid_t id, passwd_state_t* passwd_state); 76 bool FindByName(const char* name, passwd_state_t* passwd_state); Unmap()77 void Unmap() { 78 mmap_file_.Unmap(); 79 } 80 81 BIONIC_DISALLOW_IMPLICIT_CONSTRUCTORS(PasswdFile); 82 83 private: 84 MmapFile mmap_file_; 85 }; 86 87 class GroupFile { 88 public: 89 GroupFile(const char* filename, const char* required_prefix); 90 91 bool FindById(gid_t id, group_state_t* group_state); 92 bool FindByName(const char* name, group_state_t* group_state); Unmap()93 void Unmap() { 94 mmap_file_.Unmap(); 95 } 96 97 BIONIC_DISALLOW_IMPLICIT_CONSTRUCTORS(GroupFile); 98 99 private: 100 MmapFile mmap_file_; 101 }; 102