1 /* 2 * Copyright (C) 2016 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 _EEDATA_H_ 18 #define _EEDATA_H_ 19 20 #include <stdbool.h> 21 #include <stdint.h> 22 23 /* 24 * EEDATA allows storage of data in a persistent area that survives reboots and OS updates. 25 * Each data piece has a name and stores 0..EE_DATA_LEN_MAX bytes of data. The name is a 26 * non-zero number in the range 0..EE_DATA_NAME_MAX - 1. All names below EE_DATA_FIRST_USER 27 * are reserved for OS purposes and are not accessible using the external-app-visible API. 28 * To store an EEDATA item, use eeDataSet(). Setting the buffer to NULL will delete an 29 * existing item and not replace it. Otherwise an item is replaced. Return value is success 30 * (deleting a non-existent item always suceeds). You can use eeDataGet() to get items. It 31 * will return true if an item exists. If called with buf set to NULL and szP not NULL, 32 * *szP will be filled with its size. Else if buf and szP are both not NULL, up to *szP 33 * bytes will be stored into buf, and *szP will be updated with the number of bytes written. 34 * True is returned if the data item exists at all, else false is. For encryption keys, we 35 * [ab]use eeDataGetAllVersions to get all keys (as each has the same name). 36 */ 37 38 39 40 #define EE_DATA_NAME_MAX 0x000FFFFF 41 #define EE_DATA_LEN_MAX 0x00000FFF //in bytes 42 #define EE_DATA_FIRST_USER 0x00000100 43 44 45 bool eeDataGet(uint32_t name, void *buf, uint32_t *szP); 46 bool eeDataSet(uint32_t name, const void *buf, uint32_t len); 47 48 uint32_t eeDataGetSize(); 49 uint32_t eeDataGetFree(); 50 51 //allow getting old "versions". Set state to NULL initially, call till you get NULL as return value 52 void *eeDataGetAllVersions(uint32_t name, void *buf, uint32_t *szP, void **stateP); 53 bool eeDataEraseOldVersion(uint32_t name, void *addr); // addr is non-NULL address returned by call to eeDataGetAllVersions 54 55 //predefined key types 56 57 #define EE_DATA_NAME_ENCR_KEY 1 58 59 60 61 #endif 62 63