Add remote config for requirePqRatio.

app/src/main/java/org/thoughtcrime/securesms/crypto/storage/TextSecureSessionStore.java

@@ -12,6 +12,7 @@ import org.thoughtcrime.securesms.database.SessionTable;
 import org.thoughtcrime.securesms.database.SignalDatabase;
 import org.thoughtcrime.securesms.recipients.Recipient;
 import org.thoughtcrime.securesms.recipients.RecipientId;
+import org.thoughtcrime.securesms.util.RemoteConfig;
 import org.whispersystems.signalservice.api.SignalServiceSessionStore;
 import org.whispersystems.signalservice.api.SignalSessionLock;
 import org.signal.core.models.ServiceId;
@@ -76,7 +77,7 @@ public class TextSecureSessionStore implements SignalServiceSessionStore {
     try (SignalSessionLock.Lock unused = ReentrantSessionLock.INSTANCE.acquire()) {
       SessionRecord sessionRecord = SignalDatabase.sessions().load(accountId, address);
 
-      return sessionRecord != null && sessionRecord.hasSenderChain(0.0);
+      return sessionRecord != null && sessionRecord.hasSenderChain(RemoteConfig.requirePqRatio());
     }
   }
 
@@ -188,6 +189,6 @@ public class TextSecureSessionStore implements SignalServiceSessionStore {
   }
 
   private static boolean isActive(@Nullable SessionRecord record) {
-    return record != null && record.hasSenderChain(0.0);
+    return record != null && record.hasSenderChain(RemoteConfig.requirePqRatio());
   }
 }

app/src/main/java/org/thoughtcrime/securesms/messages/protocol/BufferedSessionStore.kt

@@ -5,6 +5,7 @@ import org.signal.libsignal.protocol.NoSessionException
 import org.signal.libsignal.protocol.SignalProtocolAddress
 import org.signal.libsignal.protocol.state.SessionRecord
 import org.thoughtcrime.securesms.database.SignalDatabase
+import org.thoughtcrime.securesms.util.RemoteConfig
 import org.whispersystems.signalservice.api.SignalServiceAccountDataStore
 import org.whispersystems.signalservice.api.SignalServiceSessionStore
 import kotlin.jvm.Throws
@@ -76,7 +77,7 @@ class BufferedSessionStore(private val selfServiceId: ServiceId) : SignalService
 
       if (fromDatabase != null) {
         store[address] = fromDatabase
-        return fromDatabase.hasSenderChain(0.0)
+        return fromDatabase.hasSenderChain(RemoteConfig.requirePqRatio)
       } else {
         false
       }

app/src/main/java/org/thoughtcrime/securesms/util/RemoteConfig.kt

@@ -369,6 +369,13 @@ object RemoteConfig {
     }
   }
 
+  private fun Any?.asDouble(defaultValue: Double): Double {
+    return when (this) {
+      is String -> this.toDoubleOrNull() ?: defaultValue
+      else -> defaultValue
+    }
+  }
+
   private fun <T : String?> Any?.asString(defaultValue: T): T {
     @Suppress("UNCHECKED_CAST")
     return when (this) {
@@ -486,6 +493,23 @@ object RemoteConfig {
     )
   }
 
+  private fun remoteDouble(
+    key: String,
+    defaultValue: Double,
+    hotSwappable: Boolean,
+    active: Boolean = true,
+    onChangeListener: OnFlagChange? = null
+  ): Config<Double> {
+    return remoteValue(
+      key = key,
+      hotSwappable = hotSwappable,
+      sticky = false,
+      active = active,
+      onChangeListener = onChangeListener,
+      transformer = { it.asDouble(defaultValue) }
+    )
+  }
+
   private fun remoteDuration(
     key: String,
     defaultValue: Duration,
@@ -1387,5 +1411,18 @@ object RemoteConfig {
     hotSwappable = true
   )
 
+  /**
+   * A ratio between 0 and 1, where 0 means that a session is never archived due
+   * to a lack of PQ, and 1 means that a session is always archived due to a
+   * lack of PQ.
+   */
+  @JvmStatic
+  @get:JvmName("requirePqRatio")
+  val requirePqRatio: Double by remoteDouble(
+    key = "android.requirePqRatio",
+    defaultValue = 0.0,
+    hotSwappable = true
+  )
+
   // endregion
 }