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