From: Johan Hedberg <johan.hedberg@intel.com>
Date: Tue, 27 Jan 2015 10:55:52 +0000 (+0200)
Subject: Bluetooth: Enforce zero-valued hash/rand192 for LE OOB
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=d25b78e2ed60ea33dc1008d0f50b3410b73212a0;p=linux-beck.git

Bluetooth: Enforce zero-valued hash/rand192 for LE OOB

Until legacy SMP OOB pairing is implemented user space should be given a
clear error when trying to use it. This patch adds a corresponding check
to the Add Remote OOB Data handler function which returns "invalid
parameters" if non-zero Rand192 or Hash192 parameters were given for an
LE address.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
---

diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
index 25e40e82b9a2..8417ab387d1a 100644
--- a/net/bluetooth/mgmt.c
+++ b/net/bluetooth/mgmt.c
@@ -131,6 +131,9 @@ static const u16 mgmt_events[] = {
 
 #define CACHE_TIMEOUT	msecs_to_jiffies(2 * 1000)
 
+#define ZERO_KEY "\x00\x00\x00\x00\x00\x00\x00\x00" \
+		 "\x00\x00\x00\x00\x00\x00\x00\x00"
+
 struct pending_cmd {
 	struct list_head list;
 	u16 opcode;
@@ -3673,6 +3676,18 @@ static int add_remote_oob_data(struct sock *sk, struct hci_dev *hdev,
 		u8 status;
 
 		if (bdaddr_type_is_le(cp->addr.type)) {
+			/* Enforce zero-valued 192-bit parameters as
+			 * long as legacy SMP OOB isn't implemented.
+			 */
+			if (memcmp(cp->rand192, ZERO_KEY, 16) ||
+			    memcmp(cp->hash192, ZERO_KEY, 16)) {
+				err = cmd_complete(sk, hdev->id,
+						   MGMT_OP_ADD_REMOTE_OOB_DATA,
+						   MGMT_STATUS_INVALID_PARAMS,
+						   addr, sizeof(*addr));
+				goto unlock;
+			}
+
 			rand192 = NULL;
 			hash192 = NULL;
 		} else {