DivestOS/Patches/LineageOS-18.1/android_system_bt/405364-backport.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Himanshu Rawat <rwt@google.com>
Date: Mon, 8 Apr 2024 19:42:21 +0000
Subject: [PATCH] RESTRICT AUTOMERGE Disallow unexpected incoming HID
 connections 1/2

HID profile accepted any new incoming HID connection. Even when the
connection policy disabled HID connection, remote devices could initiate
HID connection.
This change ensures that incoming HID connection are accepted only if
application was interested in that HID connection.
This vulnerarbility no longer exists on the main because of feature
request b/324093729.

Test: Manual | Pair and connect a HID device, disable HID connection
from Bluetooth device setting, attempt to connect from the HID device.
Bug: 308429049
Ignore-AOSP-First: security
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:18c635ad7923f5c26d6cd4cf7f7c66b2fa02462b)
Merged-In: I6e9db983e752dd498625078c13b736cd4c668806
Change-Id: I6e9db983e752dd498625078c13b736cd4c668806
---
 btif/include/btif_hh.h      |  4 +-
 btif/include/btif_storage.h | 23 ++++++++++
 btif/src/btif_hh.cc         | 86 ++++++++++++++++++++++++++++++++++---
 btif/src/btif_storage.cc    | 52 +++++++++++++++++++++-
 include/hardware/bt_hh.h    |  2 +-
 5 files changed, 159 insertions(+), 8 deletions(-)

diff --git a/btif/include/btif_hh.h b/btif/include/btif_hh.h
index b71d347c1..ba51aec98 100644
--- a/btif/include/btif_hh.h
+++ b/btif/include/btif_hh.h
@@ -78,6 +78,7 @@ typedef struct {
   uint8_t dev_handle;
   RawAddress bd_addr;
   tBTA_HH_ATTR_MASK attr_mask;
+  bool reconnect_allowed;
 } btif_hh_added_device_t;
 
 /**
@@ -103,7 +104,8 @@ extern btif_hh_cb_t btif_hh_cb;
 extern btif_hh_device_t* btif_hh_find_connected_dev_by_handle(uint8_t handle);
 extern void btif_hh_remove_device(RawAddress bd_addr);
 extern bool btif_hh_add_added_dev(const RawAddress& bda,
-                                  tBTA_HH_ATTR_MASK attr_mask);
+                                  tBTA_HH_ATTR_MASK attr_mask,
+                                  bool reconnect_allowed);
 extern bt_status_t btif_hh_virtual_unplug(const RawAddress* bd_addr);
 extern void btif_hh_disconnect(RawAddress* bd_addr);
 extern void btif_hh_setreport(btif_hh_device_t* p_dev,
diff --git a/btif/include/btif_storage.h b/btif/include/btif_storage.h
index 1c1163d14..362ffdc21 100644
--- a/btif/include/btif_storage.h
+++ b/btif/include/btif_storage.h
@@ -178,6 +178,29 @@ bt_status_t btif_storage_remove_bonded_device(const RawAddress* remote_bd_addr);
  ******************************************************************************/
 bt_status_t btif_storage_load_bonded_devices(void);
 
+/*******************************************************************************
+ *
+ * Function         btif_storage_set_hid_connection_policy
+ *
+ * Description      Stores connection policy info in nvram
+ *
+ * Returns          BT_STATUS_SUCCESS
+ *
+ ******************************************************************************/
+bt_status_t btif_storage_set_hid_connection_policy(const RawAddress& addr,
+                                                   bool reconnect_allowed);
+/*******************************************************************************
+ *
+ * Function         btif_storage_get_hid_connection_policy
+ *
+ * Description      get connection policy info from nvram
+ *
+ * Returns          BT_STATUS_SUCCESS
+ *
+ ******************************************************************************/
+bt_status_t btif_storage_get_hid_connection_policy(const RawAddress& addr,
+                                                   bool* reconnect_allowed);
+
 /*******************************************************************************
  *
  * Function         btif_storage_add_hid_device_info
diff --git a/btif/src/btif_hh.cc b/btif/src/btif_hh.cc
index 97479e040..41636d368 100644
--- a/btif/src/btif_hh.cc
+++ b/btif/src/btif_hh.cc
@@ -334,6 +334,24 @@ btif_hh_device_t* btif_hh_find_connected_dev_by_handle(uint8_t handle) {
   return NULL;
 }
 
+/*******************************************************************************
+ *
+ * Function         btif_hh_find_added_dev
+ *
+ * Description      Return the added device pointer of the specified address
+ *
+ * Returns          Added device entry
+ ******************************************************************************/
+btif_hh_added_device_t* btif_hh_find_added_dev(const RawAddress& addr) {
+  for (int i = 0; i < BTIF_HH_MAX_ADDED_DEV; i++) {
+    btif_hh_added_device_t* added_dev = &btif_hh_cb.added_devices[i];
+    if (added_dev->bd_addr == addr) {
+      return added_dev;
+    }
+  }
+  return nullptr;
+}
+
 /*******************************************************************************
  *
  * Function         btif_hh_find_dev_by_bda
@@ -419,7 +437,8 @@ void btif_hh_start_vup_timer(const RawAddress* bd_addr) {
  *
  * Returns          true if add successfully, otherwise false.
  ******************************************************************************/
-bool btif_hh_add_added_dev(const RawAddress& bda, tBTA_HH_ATTR_MASK attr_mask) {
+bool btif_hh_add_added_dev(const RawAddress& bda, tBTA_HH_ATTR_MASK attr_mask,
+                           bool reconnect_allowed) {
   int i;
   for (i = 0; i < BTIF_HH_MAX_ADDED_DEV; i++) {
     if (btif_hh_cb.added_devices[i].bd_addr == bda) {
@@ -433,6 +452,7 @@ bool btif_hh_add_added_dev(const RawAddress& bda, tBTA_HH_ATTR_MASK attr_mask) {
       btif_hh_cb.added_devices[i].bd_addr = bda;
       btif_hh_cb.added_devices[i].dev_handle = BTA_HH_INVALID_HANDLE;
       btif_hh_cb.added_devices[i].attr_mask = attr_mask;
+      btif_hh_cb.added_devices[i].reconnect_allowed = reconnect_allowed;
       return true;
     }
   }
@@ -712,6 +732,23 @@ void btif_hh_getreport(btif_hh_device_t* p_dev, bthh_report_type_t r_type,
  *
  ****************************************************************************/
 
+static bool btif_hh_connection_allowed(const RawAddress& bda) {
+  /* Accept connection only if reconnection is allowed for the known device, or
+   * outgoing connection was requested */
+  btif_hh_added_device_t* added_dev = btif_hh_find_added_dev(bda);
+  if (added_dev != nullptr && added_dev->reconnect_allowed) {
+    LOG_VERBOSE("Connection allowed %s", PRIVATE_ADDRESS(bda));
+    return true;
+  } else if (btif_hh_cb.pending_conn_address == bda) {
+    LOG_VERBOSE("Device connection was pending for: %s, status: %s",
+                PRIVATE_ADDRESS(bda),
+                btif_hh_status_text(btif_hh_cb.status).c_str());
+    return true;
+  }
+
+  return false;
+}
+
 /*******************************************************************************
  *
  * Function         btif_hh_upstreams_evt
@@ -770,9 +807,26 @@ static void btif_hh_upstreams_evt(uint16_t event, char* p_param) {
             p_data->status);
       break;
 
-    case BTA_HH_OPEN_EVT:
+    case BTA_HH_OPEN_EVT: {
       BTIF_TRACE_WARNING("%s: BTA_HH_OPN_EVT: handle=%d, status =%d", __func__,
                          p_data->conn.handle, p_data->conn.status);
+
+      if (!btif_hh_connection_allowed(p_data->conn.bda)) {
+        LOG_WARN("Reject Incoming HID Connection, device: %s",
+                 PRIVATE_ADDRESS(p_data->conn.bda));
+        btif_hh_device_t* p_dev =
+            btif_hh_find_connected_dev_by_handle(p_data->conn.handle);
+        if (p_dev != nullptr) {
+          p_dev->dev_status = BTHH_CONN_STATE_DISCONNECTED;
+        }
+
+        btif_hh_cb.status = (BTIF_HH_STATUS)BTIF_HH_DEV_DISCONNECTED;
+        BTA_HhClose(p_data->conn.handle);
+        HAL_CBACK(bt_hh_callbacks, connection_state_cb, &p_data->conn.bda,
+                  BTHH_CONN_STATE_DISCONNECTED);
+        return;
+      }
+
       btif_hh_cb.pending_conn_address = RawAddress::kEmpty;
       if (p_data->conn.status == BTA_HH_OK) {
         p_dev = btif_hh_find_connected_dev_by_handle(p_data->conn.handle);
@@ -831,6 +885,7 @@ static void btif_hh_upstreams_evt(uint16_t event, char* p_param) {
         btif_hh_cb.status = (BTIF_HH_STATUS)BTIF_HH_DEV_DISCONNECTED;
       }
       break;
+    }
 
     case BTA_HH_CLOSE_EVT:
       BTIF_TRACE_DEBUG("BTA_HH_CLOSE_EVT: status = %d, handle = %d",
@@ -983,7 +1038,7 @@ static void btif_hh_upstreams_evt(uint16_t event, char* p_param) {
                                 p_data->dscp_info.version,
                                 p_data->dscp_info.ctry_code, len,
                                 p_data->dscp_info.descriptor.dsc_list);
-        if (btif_hh_add_added_dev(p_dev->bd_addr, p_dev->attr_mask)) {
+        if (btif_hh_add_added_dev(p_dev->bd_addr, p_dev->attr_mask, true)) {
           tBTA_HH_DEV_DSCP_INFO dscp_info;
           bt_status_t ret;
           btif_hh_copy_hid_info(&dscp_info, &p_data->dscp_info);
@@ -999,6 +1054,8 @@ static void btif_hh_upstreams_evt(uint16_t event, char* p_param) {
               p_data->dscp_info.ssr_min_tout, len,
               p_data->dscp_info.descriptor.dsc_list);
 
+          btif_storage_set_hid_connection_policy(p_dev->bd_addr, true);
+
           ASSERTC(ret == BT_STATUS_SUCCESS, "storing hid info failed", ret);
           BTIF_TRACE_WARNING("BTA_HH_GET_DSCP_EVT: Called add device");
 
@@ -1280,6 +1337,13 @@ static bt_status_t init(bthh_callbacks_t* callbacks) {
  ******************************************************************************/
 static bt_status_t connect(RawAddress* bd_addr) {
   if (btif_hh_cb.status != BTIF_HH_DEV_CONNECTING) {
+    /* If the device was already added, ensure that reconnections are allowed */
+    btif_hh_added_device_t* added_dev = btif_hh_find_added_dev(*bd_addr);
+    if (added_dev != nullptr && !added_dev->reconnect_allowed) {
+      added_dev->reconnect_allowed = true;
+      btif_storage_set_hid_connection_policy(*bd_addr, true);
+    }
+
     btif_transfer_context(btif_hh_handle_evt, BTIF_HH_CONNECT_REQ_EVT,
                           (char*)bd_addr, sizeof(RawAddress), NULL);
     return BT_STATUS_SUCCESS;
@@ -1296,7 +1360,7 @@ static bt_status_t connect(RawAddress* bd_addr) {
  * Returns         bt_status_t
  *
  ******************************************************************************/
-static bt_status_t disconnect(RawAddress* bd_addr) {
+static bt_status_t disconnect(RawAddress* bd_addr, bool reconnect_allowed) {
   CHECK_BTHH_INIT();
   BTIF_TRACE_EVENT("BTHH: %s", __func__);
   btif_hh_device_t* p_dev;
@@ -1306,6 +1370,17 @@ static bt_status_t disconnect(RawAddress* bd_addr) {
                        btif_hh_cb.status);
     return BT_STATUS_FAIL;
   }
+
+  if (!reconnect_allowed) {
+    LOG_INFO("Incoming reconnections disabled for device %s",
+             PRIVATE_ADDRESS((*bd_addr)));
+    btif_hh_added_device_t* added_dev = btif_hh_find_added_dev(*bd_addr);
+    if (added_dev != nullptr && added_dev->reconnect_allowed) {
+      added_dev->reconnect_allowed = false;
+      btif_storage_set_hid_connection_policy(added_dev->bd_addr, false);
+    }
+  }
+
   p_dev = btif_hh_find_connected_dev_by_bda(*bd_addr);
   if (p_dev != NULL) {
     return btif_transfer_context(btif_hh_handle_evt, BTIF_HH_DISCONNECT_REQ_EVT,
@@ -1437,9 +1512,10 @@ static bt_status_t set_info(RawAddress* bd_addr, bthh_hid_info_t hid_info) {
       (uint8_t*)osi_malloc(dscp_info.descriptor.dl_len);
   memcpy(dscp_info.descriptor.dsc_list, &(hid_info.dsc_list), hid_info.dl_len);
 
-  if (btif_hh_add_added_dev(*bd_addr, hid_info.attr_mask)) {
+  if (btif_hh_add_added_dev(*bd_addr, hid_info.attr_mask, true)) {
     BTA_HhAddDev(*bd_addr, hid_info.attr_mask, hid_info.sub_class,
                  hid_info.app_id, dscp_info);
+    btif_storage_set_hid_connection_policy(*bd_addr, true);
   }
 
   osi_free_and_reset((void**)&dscp_info.descriptor.dsc_list);
diff --git a/btif/src/btif_storage.cc b/btif/src/btif_storage.cc
index 95e4ef071..c8205da09 100644
--- a/btif/src/btif_storage.cc
+++ b/btif/src/btif_storage.cc
@@ -83,6 +83,8 @@ using bluetooth::Uuid;
 #define BTIF_STORAGE_KEY_LOCAL_IO_CAPS_BLE "LocalIOCapsBLE"
 #define BTIF_STORAGE_KEY_ADAPTER_DISC_TIMEOUT "DiscoveryTimeout"
 
+#define BTIF_STORAGE_KEY_HID_RECONNECT_ALLOWED "HidReConnectAllowed"
+
 /* This is a local property to add a device found */
 #define BT_PROPERTY_REMOTE_DEVICE_TIMESTAMP 0xFF
 
@@ -1323,6 +1325,50 @@ bt_status_t btif_storage_get_remote_addr_type(const RawAddress* remote_bd_addr,
       btif_config_get_int(remote_bd_addr->ToString(), "AddrType", addr_type);
   return ret ? BT_STATUS_SUCCESS : BT_STATUS_FAIL;
 }
+
+/*******************************************************************************
+ *
+ * Function         btif_storage_set_hid_connection_policy
+ *
+ * Description      Stores connection policy info in nvram
+ *
+ * Returns          BT_STATUS_SUCCESS
+ *
+ ******************************************************************************/
+bt_status_t btif_storage_set_hid_connection_policy(const RawAddress& addr,
+                                                   bool reconnect_allowed) {
+  std::string bdstr = addr.ToString();
+
+  if (btif_config_set_int(bdstr, BTIF_STORAGE_KEY_HID_RECONNECT_ALLOWED,
+                          reconnect_allowed)) {
+    return BT_STATUS_SUCCESS;
+  } else {
+    return BT_STATUS_FAIL;
+  }
+}
+
+/*******************************************************************************
+ *
+ * Function         btif_storage_get_hid_connection_policy
+ *
+ * Description      get connection policy info from nvram
+ *
+ * Returns          BT_STATUS_SUCCESS
+ *
+ ******************************************************************************/
+bt_status_t btif_storage_get_hid_connection_policy(const RawAddress& addr,
+                                                   bool* reconnect_allowed) {
+  std::string bdstr = addr.ToString();
+
+  // For backward compatibility, assume that the reconnection is allowed in the
+  // absence of the key
+  int value = 1;
+  btif_config_get_int(bdstr, BTIF_STORAGE_KEY_HID_RECONNECT_ALLOWED, &value);
+  *reconnect_allowed = (value != 0);
+
+  return BT_STATUS_SUCCESS;
+}
+
 /*******************************************************************************
  *
  * Function         btif_storage_add_hid_device_info
@@ -1425,8 +1471,11 @@ bt_status_t btif_storage_load_bonded_hid_info(void) {
 
     RawAddress bd_addr;
     RawAddress::FromString(name, bd_addr);
+
+    bool reconnect_allowed = false;
+    btif_storage_get_hid_connection_policy(bd_addr, &reconnect_allowed);
     // add extracted information to BTA HH
-    if (btif_hh_add_added_dev(bd_addr, attr_mask)) {
+    if (btif_hh_add_added_dev(bd_addr, attr_mask, reconnect_allowed)) {
       BTA_HhAddDev(bd_addr, attr_mask, sub_class, app_id, dscp_info);
     }
   }
@@ -1458,6 +1507,7 @@ bt_status_t btif_storage_remove_hid_info(RawAddress* remote_bd_addr) {
   btif_config_remove(bdstr, "HidSSRMaxLatency");
   btif_config_remove(bdstr, "HidSSRMinTimeout");
   btif_config_remove(bdstr, "HidDescriptor");
+  btif_config_remove(bdstr, BTIF_STORAGE_KEY_HID_RECONNECT_ALLOWED);
   btif_config_save();
   return BT_STATUS_SUCCESS;
 }
diff --git a/include/hardware/bt_hh.h b/include/hardware/bt_hh.h
index b87b129bb..923c62792 100644
--- a/include/hardware/bt_hh.h
+++ b/include/hardware/bt_hh.h
@@ -154,7 +154,7 @@ typedef struct {
   bt_status_t (*connect)(RawAddress* bd_addr);
 
   /** dis-connect from hid device */
-  bt_status_t (*disconnect)(RawAddress* bd_addr);
+  bt_status_t (*disconnect)(RawAddress* bd_addr, bool reconnect_allowed);
 
   /** Virtual UnPlug (VUP) the specified HID device */
   bt_status_t (*virtual_unplug)(RawAddress* bd_addr);