DivestOS/Patches/LineageOS-17.1/android_system_bt/399092.patch
Tavi 7251c3f1d1
Churn
Signed-off-by: Tavi <tavi@divested.dev>
2024-08-17 12:35:07 -04:00

64 lines
2.3 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Brian Delwiche <delwiche@google.com>
Date: Mon, 22 Apr 2024 21:14:56 +0000
Subject: [PATCH] Fix an authentication bypass bug in SMP
When pairing with BLE legacy pairing initiated
from remote, authentication can be bypassed.
This change fixes it.
Bug: 251514170
Test: m com.android.btservices
Test: manual run against PoC
Ignore-AOSP-First: security
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:8a3dbadc71428a30b172a74343be08498c656747)
Merged-In: I66b1f9a80060f48a604001829db8ea7c96c7b7f8
Change-Id: I66b1f9a80060f48a604001829db8ea7c96c7b7f8
---
stack/smp/smp_act.cc | 12 ++++++++++++
stack/smp/smp_int.h | 1 +
2 files changed, 13 insertions(+)
diff --git a/stack/smp/smp_act.cc b/stack/smp/smp_act.cc
index c1f143e92..199c5abb3 100644
--- a/stack/smp/smp_act.cc
+++ b/stack/smp/smp_act.cc
@@ -284,6 +284,7 @@ void smp_send_pair_rsp(tSMP_CB* p_cb, tSMP_INT_DATA* p_data) {
void smp_send_confirm(tSMP_CB* p_cb, tSMP_INT_DATA* p_data) {
SMP_TRACE_DEBUG("%s", __func__);
smp_send_cmd(SMP_OPCODE_CONFIRM, p_cb);
+ p_cb->flags |= SMP_PAIR_FLAGS_CMD_CONFIRM_SENT;
}
/*******************************************************************************
@@ -645,6 +646,17 @@ void smp_proc_init(tSMP_CB* p_cb, tSMP_INT_DATA* p_data) {
return;
}
+ if (!((p_cb->loc_auth_req & SMP_SC_SUPPORT_BIT) &&
+ (p_cb->peer_auth_req & SMP_SC_SUPPORT_BIT)) &&
+ !(p_cb->flags & SMP_PAIR_FLAGS_CMD_CONFIRM_SENT)) {
+ // in legacy pairing, the peer should send its rand after
+ // we send our confirm
+ tSMP_INT_DATA smp_int_data{};
+ smp_int_data.status = SMP_INVALID_PARAMETERS;
+ smp_sm_event(p_cb, SMP_AUTH_CMPL_EVT, &smp_int_data);
+ return;
+ }
+
/* save the SRand for comparison */
STREAM_TO_ARRAY(p_cb->rrand.data(), p, OCTET16_LEN);
}
diff --git a/stack/smp/smp_int.h b/stack/smp/smp_int.h
index 72fdf55a9..e3063c57d 100644
--- a/stack/smp/smp_int.h
+++ b/stack/smp/smp_int.h
@@ -241,6 +241,7 @@ typedef union {
(1 << 7) /* used to resolve race condition */
#define SMP_PAIR_FLAG_HAVE_LOCAL_PUBL_KEY \
(1 << 8) /* used on slave to resolve race condition */
+#define SMP_PAIR_FLAGS_CMD_CONFIRM_SENT (1 << 9)
/* check if authentication requirement need MITM protection */
#define SMP_NO_MITM_REQUIRED(x) (((x)&SMP_AUTH_YN_BIT) == 0)