/* * Copyright (C) 2022 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.android.server.uwb.discovery.info; import android.annotation.NonNull; import android.annotation.Nullable; import android.util.Log; import com.android.server.uwb.util.ArrayUtils; import com.android.server.uwb.util.DataTypeConversionUtil; import com.google.common.primitives.Bytes; import java.nio.ByteBuffer; import java.util.ArrayList; import java.util.Arrays; import java.util.List; /** * Holds the UWB Indication Data according to FiRa BLE OOB v1.0 specification. */ public class UwbIndicationData { private static final String LOG_TAG = UwbIndicationData.class.getSimpleName(); // Minimum size of the full data private static final int UWB_INDICATION_DATA_SIZE = 2; // The capabilities field within UWB indication data private static final byte FIRA_UWB_SUPPORT_BITMASK = (byte) 0x80; private static final byte ISO14443_SUPPORT_BITMASK = 0x40; private static final byte UWB_REGULATORY_INFO_AVAILABLE_IN_AD_BITMASK = 0x20; private static final byte UWB_REGULATORY_INFO_AVAILABLE_IN_OOB_BITMASK = 0x10; private static final byte FIRA_PROFILE_INFO_AVAILABLE_IN_AD_BITMASK = 0x08; private static final byte FIRA_PROFILE_INFO_AVAILABLE_IN_OOB_BITMASK = 0x04; private static final byte CAPABILITIES_RESERVED_FIELD_BITMASK = 0x02; private static final byte CAPABILITIES_RESERVED_FIELD_DATA = 0x0; private static final byte DUAL_GAP_ROLE_SUPPORT_BITMASK = 0x01; public final boolean firaUwbSupport; public final boolean iso14443Support; public final boolean uwbRegulartoryInfoAvailableInAd; public final boolean uwbRegulartoryInfoAvailableInOob; public final boolean firaProfileInfoAvailableInAd; public final boolean firaProfileInfoAvailableInOob; public final boolean dualGapRoleSupport; public final int bluetoothRssiThresholdDbm; public final SecureComponentInfo[] secureComponentInfos; /** * Generate the UwbIndicationData from raw bytes array. * * @param bytes byte array containing the UWB Indication Data encoding based on the FiRa * specification. * @return decode bytes into {@link UwbIndicationData}, else null if invalid. */ @Nullable public static UwbIndicationData fromBytes(@NonNull byte[] bytes) { if (ArrayUtils.isEmpty(bytes)) { logw("Failed to convert empty into UWB Indication Data."); return null; } if (bytes.length < UWB_INDICATION_DATA_SIZE) { logw("Failed to convert bytes into UWB Indication Data due to invalid data size."); return null; } ByteBuffer byteBuffer = ByteBuffer.wrap(bytes); byte uwbCapabilities = byteBuffer.get(); boolean firaUwbSupport = (uwbCapabilities & FIRA_UWB_SUPPORT_BITMASK) != 0; boolean iso14443Support = (uwbCapabilities & ISO14443_SUPPORT_BITMASK) != 0; boolean uwbRegulartoryInfoAvailableInAd = (uwbCapabilities & UWB_REGULATORY_INFO_AVAILABLE_IN_AD_BITMASK) != 0; boolean uwbRegulartoryInfoAvailableInOob = (uwbCapabilities & UWB_REGULATORY_INFO_AVAILABLE_IN_OOB_BITMASK) != 0; boolean firaProfileInfoAvailableInAd = (uwbCapabilities & FIRA_PROFILE_INFO_AVAILABLE_IN_AD_BITMASK) != 0; boolean firaProfileInfoAvailableInOob = (uwbCapabilities & FIRA_PROFILE_INFO_AVAILABLE_IN_OOB_BITMASK) != 0; boolean dualGapRoleSupport = (uwbCapabilities & DUAL_GAP_ROLE_SUPPORT_BITMASK) != 0; byte capabilitiesReservedField = (byte) (uwbCapabilities & CAPABILITIES_RESERVED_FIELD_BITMASK); if (capabilitiesReservedField != CAPABILITIES_RESERVED_FIELD_DATA) { logw( "Failed to convert bytes into UWB Indication Data due to reserved field in uwb" + " capabilities is unmatched"); return null; } int bluetoothRssiThresholdDbm = (int) byteBuffer.get(); int info_size = (bytes.length - UWB_INDICATION_DATA_SIZE) / SecureComponentInfo.size(); List infos = new ArrayList<>(); for (int i = 0; i < info_size; i++) { byte[] secureComponentInfoBytes = new byte[SecureComponentInfo.size()]; byteBuffer.get(secureComponentInfoBytes); SecureComponentInfo info = SecureComponentInfo.fromBytes(secureComponentInfoBytes); if (info != null) { infos.add(info); } } return new UwbIndicationData( firaUwbSupport, iso14443Support, uwbRegulartoryInfoAvailableInAd, uwbRegulartoryInfoAvailableInOob, firaProfileInfoAvailableInAd, firaProfileInfoAvailableInOob, dualGapRoleSupport, bluetoothRssiThresholdDbm, infos.toArray(new SecureComponentInfo[0])); } /** * Generate raw bytes array from UwbIndicationData. * * @param info the UWB Indication Data * @return encoded bytes into byte array based on the FiRa specification. */ public static byte[] toBytes(@NonNull UwbIndicationData info) { byte[] data = new byte[] { convertCapabilitiesField(info), DataTypeConversionUtil.i32ToByteArray(info.bluetoothRssiThresholdDbm)[3] }; for (SecureComponentInfo i : info.secureComponentInfos) { data = Bytes.concat(data, SecureComponentInfo.toBytes(i)); } return data; } private static byte convertCapabilitiesField(@NonNull UwbIndicationData info) { return (byte) ((((info.firaUwbSupport ? 1 : 0) << 7) & FIRA_UWB_SUPPORT_BITMASK) | (((info.iso14443Support ? 1 : 0) << 6) & ISO14443_SUPPORT_BITMASK) | (((info.uwbRegulartoryInfoAvailableInAd ? 1 : 0) << 5) & UWB_REGULATORY_INFO_AVAILABLE_IN_AD_BITMASK) | (((info.uwbRegulartoryInfoAvailableInOob ? 1 : 0) << 4) & UWB_REGULATORY_INFO_AVAILABLE_IN_OOB_BITMASK) | (((info.firaProfileInfoAvailableInAd ? 1 : 0) << 3) & FIRA_PROFILE_INFO_AVAILABLE_IN_AD_BITMASK) | (((info.firaProfileInfoAvailableInOob ? 1 : 0) << 2) & FIRA_PROFILE_INFO_AVAILABLE_IN_OOB_BITMASK) | ((CAPABILITIES_RESERVED_FIELD_DATA << 1) & CAPABILITIES_RESERVED_FIELD_BITMASK) | ((info.dualGapRoleSupport ? 1 : 0) & DUAL_GAP_ROLE_SUPPORT_BITMASK)); } public UwbIndicationData( boolean firaUwbSupport, boolean iso14443Support, boolean uwbRegulartoryInfoAvailableInAd, boolean uwbRegulartoryInfoAvailableInOob, boolean firaProfileInfoAvailableInAd, boolean firaProfileInfoAvailableInOob, boolean dualGapRoleSupport, int bluetoothRssiThresholdDbm, SecureComponentInfo[] secureComponentInfos) { this.firaUwbSupport = firaUwbSupport; this.iso14443Support = iso14443Support; this.uwbRegulartoryInfoAvailableInAd = uwbRegulartoryInfoAvailableInAd; this.uwbRegulartoryInfoAvailableInOob = uwbRegulartoryInfoAvailableInOob; this.firaProfileInfoAvailableInAd = firaProfileInfoAvailableInAd; this.firaProfileInfoAvailableInOob = firaProfileInfoAvailableInOob; this.dualGapRoleSupport = dualGapRoleSupport; this.bluetoothRssiThresholdDbm = bluetoothRssiThresholdDbm; this.secureComponentInfos = secureComponentInfos; } @Override public String toString() { StringBuilder sb = new StringBuilder(); sb.append("UwbIndicationData: firaUwbSupport=") .append(firaUwbSupport) .append(" iso14443Support=") .append(iso14443Support) .append(" uwbRegulartoryInfoAvailableInAd=") .append(uwbRegulartoryInfoAvailableInAd) .append(" uwbRegulartoryInfoAvailableInOob=") .append(uwbRegulartoryInfoAvailableInOob) .append(" firaProfileInfoAvailableInAd=") .append(firaProfileInfoAvailableInAd) .append(" firaProfileInfoAvailableInOob=") .append(firaProfileInfoAvailableInOob) .append(" dualGapRoleSupport=") .append(dualGapRoleSupport) .append(" bluetoothRssiThresholdDbm=") .append(bluetoothRssiThresholdDbm) .append(" ") .append(Arrays.toString(secureComponentInfos)); return sb.toString(); } private static void logw(String log) { Log.w(LOG_TAG, log); } }