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 package com.android.weaver; 18 19 public interface Slots extends javacard.framework.Shareable { 20 /** @return The number of slots available. */ getNumSlots()21 short getNumSlots(); 22 23 /** 24 * Write the key and value to the identified slot. 25 * 26 * @param slotId ID of the slot to write to. 27 * @param key Buffer containing the key. 28 * @param keyOffset Offset of the key in the buffer. 29 * @param value Buffer containing the value. 30 * @param valueOffset Offset of the value in the buffer. 31 */ write(short slotId, byte[] key, short keyOffset, byte[] value, short valueOffset)32 void write(short slotId, byte[] key, short keyOffset, byte[] value, short valueOffset); 33 34 /** 35 * Read the value from the identified slot. 36 * 37 * This is only successful if the key matches that stored in the slot. 38 * 39 * @param slotId ID of the slot to write to. 40 * @param key Buffer containing the key. 41 * @param keyOffset Offset of the key in the buffer. 42 * @param value Buffer to receive the value. 43 * @param valueOffset Offset into the buffer to write the value. 44 * @return Status byte indicating the success or otherwise of the read. 45 */ read(short slotId, byte[] key, short keyOffset, byte[] value, short valueOffset)46 byte read(short slotId, byte[] key, short keyOffset, byte[] value, short valueOffset); 47 48 /** 49 * Set the value of the identified slot to all zeros whilst leaving the key untouched. 50 * 51 * This is used to destroy the secret stored in the slot but retain the ability to authenticate 52 * by comparing a challenege with the slot's key. 53 * 54 * @param slotId ID of the slot of which to erase the value. 55 */ eraseValue(short slotId)56 void eraseValue(short slotId); 57 58 /** Erases the key and value of all slots. */ eraseAll()59 void eraseAll(); 60 } 61