1 /* 2 * Copyright (C) 2009 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 BINDER_PERMISSION_H 18 #define BINDER_PERMISSION_H 19 20 #include <stdint.h> 21 #include <unistd.h> 22 23 #include <utils/String16.h> 24 #include <utils/Singleton.h> 25 #include <utils/SortedVector.h> 26 27 namespace android { 28 // --------------------------------------------------------------------------- 29 30 /* 31 * PermissionCache caches permission checks for a given uid. 32 * 33 * Currently the cache is not updated when there is a permission change, 34 * for instance when an application is uninstalled. 35 * 36 * IMPORTANT: for the reason stated above, only system permissions are safe 37 * to cache. This restriction may be lifted at a later time. 38 * 39 */ 40 41 class PermissionCache : Singleton<PermissionCache> { 42 struct Entry { 43 String16 name; 44 uid_t uid; 45 bool granted; 46 inline bool operator < (const Entry& e) const { 47 return (uid == e.uid) ? (name < e.name) : (uid < e.uid); 48 } 49 }; 50 mutable Mutex mLock; 51 // we pool all the permission names we see, as many permissions checks 52 // will have identical names 53 SortedVector< String16 > mPermissionNamesPool; 54 // this is our cache per say. it stores pooled names. 55 SortedVector< Entry > mCache; 56 57 // free the whole cache, but keep the permission name pool 58 void purge(); 59 60 status_t check(bool* granted, 61 const String16& permission, uid_t uid) const; 62 63 void cache(const String16& permission, uid_t uid, bool granted); 64 65 public: 66 PermissionCache(); 67 68 static bool checkCallingPermission(const String16& permission); 69 70 static bool checkCallingPermission(const String16& permission, 71 int32_t* outPid, int32_t* outUid); 72 73 static bool checkPermission(const String16& permission, 74 pid_t pid, uid_t uid); 75 }; 76 77 // --------------------------------------------------------------------------- 78 }; // namespace android 79 80 #endif /* BINDER_PERMISSION_H */ 81
