Re-implement passive-roaming.

api/rust/proto/chirpstack/internal/internal.proto

@@ -233,3 +233,34 @@ message LoraCloudGeolocBufferUplink {
     // RxInfo set for a single uplink.
     repeated gw.UplinkRxInfo rx_info = 1;
 }
+
+message PassiveRoamingDeviceSession {
+    // Session ID (UUID).
+    // Unfortunately we can not use the DevEUI as unique identifier
+    // as the PRStartAns DevEUI field is optional.
+    bytes session_id = 1;
+
+    // NetID of the hNS.
+    bytes net_id = 2;
+    
+    // DevAddr of the device.
+    bytes dev_addr = 3;
+
+    // DevEUI of the device (optional).
+    bytes dev_eui = 4;
+
+    // LoRaWAN 1.1.
+    bool lorawan_1_1 = 5;
+
+    // LoRaWAN 1.0 NwkSKey / LoRaWAN 1.1 FNwkSIntKey.
+    bytes f_nwk_s_int_key = 6;
+
+    // Lifetime.
+    google.protobuf.Timestamp lifetime = 7;
+
+    // Uplink frame-counter.
+    uint32 f_cnt_up = 8;
+
+    // Validate MIC.
+    bool validate_mic = 9;
+}