Check Classic key before cross-key derivation

[android-x86/system-bt.git] / stack / smp / smp_act.c

diff --git a/stack/smp/smp_act.c b/stack/smp/smp_act.c
index 398160c..d1b70b2 100644 (file)
--- a/stack/smp/smp_act.c
+++ b/stack/smp/smp_act.c
@@ -1351,7 +1351,19 @@ void smp_key_distribution(tSMP_CB *p_cb, tSMP_INT_DATA *p_data)
         {
             if (p_cb->derive_lk)
             {
-                smp_derive_link_key_from_long_term_key(p_cb, NULL);
+                tBTM_SEC_DEV_REC* p_dev_rec = btm_find_dev(p_cb->pairing_bda);
+                if (!(p_dev_rec->sec_flags & BTM_SEC_LE_LINK_KEY_AUTHED) &&
+                    (p_dev_rec->sec_flags & BTM_SEC_LINK_KEY_AUTHED)) {
+                  SMP_TRACE_DEBUG(
+                      "%s BR key is higher security than existing LE keys, don't "
+                      "derive LK from LTK",
+                      __func__);
+                  android_errorWriteLog(0x534e4554, "158854097");
+                }
+                else
+                {
+                  smp_derive_link_key_from_long_term_key(p_cb, NULL);
+                }
                 p_cb->derive_lk = FALSE;
             }