EN: Allow exporting key of current day

This requires rotating the daily TEK when exporting
This commit is contained in:
Marvin W 2020-12-11 11:51:53 +01:00
parent 0e0ac35e51
commit 369c3d7557
No known key found for this signature in database
GPG Key ID: 072E9235DB996F2A
4 changed files with 47 additions and 33 deletions

View File

@ -39,7 +39,7 @@
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="16dp"
tools:text="Your phonre needs to use Bluetooth to securely collect and share IDs with other phones that are nearby.\n\nCorona Warn can notify you if you were exposed to someone who reported to be diagnosed positive.\n\nThe date, duration, and signal strength associated with an exposure will be shared with the app." />
tools:text="Your phone needs to use Bluetooth to securely collect and share IDs with other phones that are nearby.\n\nCorona Warn can notify you if you were exposed to someone who reported to be diagnosed positive.\n\nThe date, duration, and signal strength associated with an exposure will be shared with the app." />
<LinearLayout
android:id="@+id/grant_permission_view"

View File

@ -34,11 +34,14 @@ private const val AES_BLOCK_SIZE = 16
private const val AEM_ALGORITHM = "AES/CTR/NoPadding"
val currentIntervalNumber: Long
get() = floor(System.currentTimeMillis() / 1000.0 / ROLLING_WINDOW_LENGTH).toLong()
val currentIntervalNumber: Int
get() = floor(System.currentTimeMillis() / 1000.0 / ROLLING_WINDOW_LENGTH).toInt()
val currentRollingStartNumber: Long
get() = floor(currentIntervalNumber.toDouble() / ROLLING_PERIOD).toLong() * ROLLING_PERIOD
val currentDayRollingStartNumber: Int
get() = getDayRollingStartNumber(currentIntervalNumber)
fun getDayRollingStartNumber(intervalNumber: Int) = (floor(currentIntervalNumber.toDouble() / ROLLING_PERIOD).toLong() * ROLLING_PERIOD).toInt()
fun getPeriodInDay(intervalNumber: Int) = intervalNumber - getDayRollingStartNumber(intervalNumber)
val nextKeyMillis: Long
get() {
@ -47,18 +50,16 @@ val nextKeyMillis: Long
return (currentWindowEnd - System.currentTimeMillis()).coerceAtLeast(0)
}
fun TemporaryExposureKey.TemporaryExposureKeyBuilder.setCurrentRollingStartNumber(): TemporaryExposureKey.TemporaryExposureKeyBuilder =
setRollingStartIntervalNumber(currentRollingStartNumber.toInt())
fun TemporaryExposureKey.TemporaryExposureKeyBuilder.generate(): TemporaryExposureKey.TemporaryExposureKeyBuilder {
fun generateTemporaryExposureKey(intervalNumber: Int): TemporaryExposureKey.TemporaryExposureKeyBuilder = TemporaryExposureKey.TemporaryExposureKeyBuilder().apply {
var keyData = ByteArray(16)
SecureRandom().nextBytes(keyData)
setKeyData(keyData)
setRollingPeriod(ROLLING_PERIOD)
return this
setRollingStartIntervalNumber(intervalNumber)
setRollingPeriod((ROLLING_PERIOD - getPeriodInDay(intervalNumber)))
}
fun generateCurrentTemporaryExposureKey(): TemporaryExposureKey = TemporaryExposureKey.TemporaryExposureKeyBuilder().generate().setCurrentRollingStartNumber().build()
fun generateCurrentDayTemporaryExposureKey(): TemporaryExposureKey = generateTemporaryExposureKey(currentDayRollingStartNumber).build()
fun generateIntraDayTemporaryExposureKey(intervalNumber: Int = currentIntervalNumber): TemporaryExposureKey = generateTemporaryExposureKey(intervalNumber).build()
@TargetApi(21)
fun TemporaryExposureKey.generateRpiKey(): SecretKeySpec {

View File

@ -15,14 +15,11 @@ import android.database.sqlite.SQLiteOpenHelper
import android.os.Parcel
import android.os.Parcelable
import android.util.Log
import com.google.android.gms.nearby.exposurenotification.CalibrationConfidence
import com.google.android.gms.nearby.exposurenotification.DiagnosisKeysDataMapping
import com.google.android.gms.nearby.exposurenotification.ExposureConfiguration
import com.google.android.gms.nearby.exposurenotification.TemporaryExposureKey
import kotlinx.coroutines.*
import okio.ByteString
import org.json.JSONObject
import org.microg.gms.nearby.exposurenotification.Constants.TOKEN_A
import java.io.File
import java.lang.Runnable
import java.nio.ByteBuffer
@ -111,7 +108,7 @@ class ExposureDatabase private constructor(private val context: Context) : SQLit
fun dailyCleanup(): Boolean = writableDatabase.run {
val start = System.currentTimeMillis()
val rollingStartTime = currentRollingStartNumber * ROLLING_WINDOW_LENGTH * 1000 - TimeUnit.DAYS.toMillis(KEEP_DAYS.toLong())
val rollingStartTime = currentDayRollingStartNumber * ROLLING_WINDOW_LENGTH * 1000 - TimeUnit.DAYS.toMillis(KEEP_DAYS.toLong())
val advertisements = delete(TABLE_ADVERTISEMENTS, "timestamp < ?", longArrayOf(rollingStartTime))
Log.d(TAG, "Deleted on daily cleanup: $advertisements adv")
if (start + MAX_DELETE_TIME < System.currentTimeMillis()) return@run false
@ -533,8 +530,9 @@ class ExposureDatabase private constructor(private val context: Context) : SQLit
}
}
private fun findOwnKeyAt(rollingStartNumber: Int, database: SQLiteDatabase = readableDatabase): TemporaryExposureKey? = database.run {
query(TABLE_TEK, arrayOf("keyData", "rollingStartNumber", "rollingPeriod"), "rollingStartNumber = ?", arrayOf(rollingStartNumber.toString()), null, null, null).use { cursor ->
private fun findOwnKeyAt(intervalNumber: Int, database: SQLiteDatabase = readableDatabase): TemporaryExposureKey? = database.run {
val dayRollingStartNumber = getDayRollingStartNumber(intervalNumber)
query(TABLE_TEK, arrayOf("keyData", "rollingStartNumber", "rollingPeriod"), "rollingStartNumber >= ? AND (rollingStartNumber + rollingPeriod) < ?", arrayOf(dayRollingStartNumber.toString(), intervalNumber.toString()), null, null, "rollingStartNumber DESC").use { cursor ->
if (cursor.moveToNext()) {
TemporaryExposureKey.TemporaryExposureKeyBuilder()
.setKeyData(cursor.getBlob(0))
@ -602,9 +600,21 @@ class ExposureDatabase private constructor(private val context: Context) : SQLit
}
}
val allKeys: List<TemporaryExposureKey> = readableDatabase.run {
val startRollingNumber = (currentRollingStartNumber - 14 * ROLLING_PERIOD)
query(TABLE_TEK, arrayOf("keyData", "rollingStartNumber", "rollingPeriod"), "rollingStartNumber >= ? AND rollingStartNumber < ?", arrayOf(startRollingNumber.toString(), currentIntervalNumber.toString()), null, null, null).use { cursor ->
fun exportKeys(database: SQLiteDatabase = writableDatabase): List<TemporaryExposureKey> = database.run {
database.beginTransactionNonExclusive()
try {
val intervalNumber = currentIntervalNumber
val key = findOwnKeyAt(intervalNumber, database)
if (key != null && intervalNumber != key.rollingStartIntervalNumber) {
// Rotate key
update(TABLE_TEK, ContentValues().apply {
put("rollingPeriod", intervalNumber - key.rollingStartIntervalNumber)
}, "rollingStartNumber = ?", arrayOf(key.rollingStartIntervalNumber.toString()))
storeOwnKey(generateIntraDayTemporaryExposureKey(intervalNumber), database)
}
database.setTransactionSuccessful()
val startRollingNumber = (getDayRollingStartNumber(intervalNumber) - 14 * ROLLING_PERIOD)
query(TABLE_TEK, arrayOf("keyData", "rollingStartNumber", "rollingPeriod"), "rollingStartNumber >= ? AND (rollingStartNumber + rollingPeriod) <= ?", arrayOf(startRollingNumber.toString(), intervalNumber.toString()), null, null, null).use { cursor ->
val list = arrayListOf<TemporaryExposureKey>()
while (cursor.moveToNext()) {
list.add(TemporaryExposureKey.TemporaryExposureKeyBuilder()
@ -615,6 +625,9 @@ class ExposureDatabase private constructor(private val context: Context) : SQLit
}
list
}
} finally {
database.endTransaction()
}
}
val rpiHistogram: Map<Long, Long>
@ -733,9 +746,9 @@ class ExposureDatabase private constructor(private val context: Context) : SQLit
private fun ensureTemporaryExposureKey(): TemporaryExposureKey = writableDatabase.let { database ->
database.beginTransactionNonExclusive()
try {
var key = findOwnKeyAt(currentRollingStartNumber.toInt(), database)
var key = findOwnKeyAt(currentIntervalNumber.toInt(), database)
if (key == null) {
key = generateCurrentTemporaryExposureKey()
key = generateCurrentDayTemporaryExposureKey()
storeOwnKey(key, database)
}
database.setTransactionSuccessful()
@ -747,7 +760,7 @@ class ExposureDatabase private constructor(private val context: Context) : SQLit
val currentRpiId: UUID?
get() {
val key = findOwnKeyAt(currentRollingStartNumber.toInt()) ?: return null
val key = findOwnKeyAt(currentIntervalNumber.toInt()) ?: return null
val buffer = ByteBuffer.wrap(key.generateRpiId(currentIntervalNumber.toInt()))
return UUID(buffer.long, buffer.long)
}

View File

@ -146,7 +146,7 @@ class ExposureNotificationServiceImpl(private val context: Context, private val
val status = confirmPermission(CONFIRM_ACTION_KEYS)
val response = when {
status.isSuccess -> ExposureDatabase.with(context) { database ->
database.allKeys
database.exportKeys()
}
else -> emptyList()
}