2011-05-25 13:49:53

by Rymarkiewicz Waldemar

Subject: [PATCH] Bluetooth: Fix auth_complete_evt for legacy units

Legacy devices don't re-authenticate the link properly if a link key
already exists. Thus, don't update sec_level for this case even if
hci_auth_complete_evt indicates success. Otherwise the sec_level will
not reflect a real security on the link.

Signed-off-by: Waldemar Rymarkiewicz <[email protected]>
---
include/net/bluetooth/hci_core.h | 1 +
net/bluetooth/hci_conn.c | 2 ++
net/bluetooth/hci_event.c | 12 ++++++++++--
3 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index 6c994c0..1af6754 100644
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -313,6 +313,7 @@ void hci_inquiry_cache_update(struct hci_dev *hdev, struct inquiry_data *data);
/* ----- HCI Connections ----- */
enum {
HCI_CONN_AUTH_PEND,
+ HCI_CONN_REAUTH_PEND,
HCI_CONN_ENCRYPT_PEND,
HCI_CONN_RSWITCH_PEND,
HCI_CONN_MODE_CHANGE_PEND,
diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c
index 3163330..e675402 100644
--- a/net/bluetooth/hci_conn.c
+++ b/net/bluetooth/hci_conn.c
@@ -548,6 +548,8 @@ static int hci_conn_auth(struct hci_conn *conn, __u8 sec_level, __u8 auth_type)
cp.handle = cpu_to_le16(conn->handle);
hci_send_cmd(conn->hdev, HCI_OP_AUTH_REQUESTED,
sizeof(cp), &cp);
+ if (conn->key_type != 0xff)
+ set_bit(HCI_CONN_REAUTH_PEND, &conn->pend);
}

return 0;
diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index f13ddbf..8b31754 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -1462,13 +1462,21 @@ static inline void hci_auth_complete_evt(struct hci_dev *hdev, struct sk_buff *s
conn = hci_conn_hash_lookup_handle(hdev, __le16_to_cpu(ev->handle));
if (conn) {
if (!ev->status) {
- conn->link_mode |= HCI_LM_AUTH;
- conn->sec_level = conn->pending_sec_level;
+ if (!(conn->ssp_mode > 0 && hdev->ssp_mode > 0) &&
+ test_bit(HCI_CONN_REAUTH_PEND,
+ &conn->pend)) {
+ BT_INFO("Re-authentication of legacy device" \
+ " is not possible.");
+ } else {
+ conn->link_mode |= HCI_LM_AUTH;
+ conn->sec_level = conn->pending_sec_level;
+ }
} else {
mgmt_auth_failed(hdev->id, &conn->dst, ev->status);
}

clear_bit(HCI_CONN_AUTH_PEND, &conn->pend);
+ clear_bit(HCI_CONN_REAUTH_PEND, &conn->pend);

if (conn->state == BT_CONFIG) {
if (!ev->status && hdev->ssp_mode > 0 &&
--
1.7.1

2011-05-25 19:53:16

by Luiz Augusto von Dentz

Subject: Re: [PATCH] Bluetooth: Fix auth_complete_evt for legacy units

Hi,

On Wed, May 25, 2011 at 4:49 PM, Waldemar Rymarkiewicz
<[email protected]> wrote:
> Legacy devices don't re-authenticate the link properly if a link key
> already exists. ?Thus, don't update sec_level for this case even if
> hci_auth_complete_evt indicates success. Otherwise the sec_level will
> not reflect a real security on the link.
>
> Signed-off-by: Waldemar Rymarkiewicz <[email protected]>
> ---
> ?include/net/bluetooth/hci_core.h | ? ?1 +
> ?net/bluetooth/hci_conn.c ? ? ? ? | ? ?2 ++
> ?net/bluetooth/hci_event.c ? ? ? ?| ? 12 ++++++++++--
> ?3 files changed, 13 insertions(+), 2 deletions(-)
>
> diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
> index 6c994c0..1af6754 100644
> --- a/include/net/bluetooth/hci_core.h
> +++ b/include/net/bluetooth/hci_core.h
> @@ -313,6 +313,7 @@ void hci_inquiry_cache_update(struct hci_dev *hdev, struct inquiry_data *data);
> ?/* ----- HCI Connections ----- */
> ?enum {
> ? ? ? ?HCI_CONN_AUTH_PEND,
> + ? ? ? HCI_CONN_REAUTH_PEND,
> ? ? ? ?HCI_CONN_ENCRYPT_PEND,
> ? ? ? ?HCI_CONN_RSWITCH_PEND,
> ? ? ? ?HCI_CONN_MODE_CHANGE_PEND,
> diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c
> index 3163330..e675402 100644
> --- a/net/bluetooth/hci_conn.c
> +++ b/net/bluetooth/hci_conn.c
> @@ -548,6 +548,8 @@ static int hci_conn_auth(struct hci_conn *conn, __u8 sec_level, __u8 auth_type)
> ? ? ? ? ? ? ? ?cp.handle = cpu_to_le16(conn->handle);
> ? ? ? ? ? ? ? ?hci_send_cmd(conn->hdev, HCI_OP_AUTH_REQUESTED,
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?sizeof(cp), &cp);
> + ? ? ? ? ? ? ? if (conn->key_type != 0xff)
> + ? ? ? ? ? ? ? ? ? ? ? set_bit(HCI_CONN_REAUTH_PEND, &conn->pend);
> ? ? ? ?}
>
> ? ? ? ?return 0;
> diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
> index f13ddbf..8b31754 100644
> --- a/net/bluetooth/hci_event.c
> +++ b/net/bluetooth/hci_event.c
> @@ -1462,13 +1462,21 @@ static inline void hci_auth_complete_evt(struct hci_dev *hdev, struct sk_buff *s
> ? ? ? ?conn = hci_conn_hash_lookup_handle(hdev, __le16_to_cpu(ev->handle));
> ? ? ? ?if (conn) {
> ? ? ? ? ? ? ? ?if (!ev->status) {
> - ? ? ? ? ? ? ? ? ? ? ? conn->link_mode |= HCI_LM_AUTH;
> - ? ? ? ? ? ? ? ? ? ? ? conn->sec_level = conn->pending_sec_level;
> + ? ? ? ? ? ? ? ? ? ? ? if (!(conn->ssp_mode > 0 && hdev->ssp_mode > 0) &&
> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? test_bit(HCI_CONN_REAUTH_PEND,
> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? &conn->pend)) {
> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? BT_INFO("Re-authentication of legacy device" \
> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? " is not possible.");
> + ? ? ? ? ? ? ? ? ? ? ? } else {
> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? conn->link_mode |= HCI_LM_AUTH;
> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? conn->sec_level = conn->pending_sec_level;
> + ? ? ? ? ? ? ? ? ? ? ? }
> ? ? ? ? ? ? ? ?} else {
> ? ? ? ? ? ? ? ? ? ? ? ?mgmt_auth_failed(hdev->id, &conn->dst, ev->status);
> ? ? ? ? ? ? ? ?}
>
> ? ? ? ? ? ? ? ?clear_bit(HCI_CONN_AUTH_PEND, &conn->pend);
> + ? ? ? ? ? ? ? clear_bit(HCI_CONN_REAUTH_PEND, &conn->pend);
>
> ? ? ? ? ? ? ? ?if (conn->state == BT_CONFIG) {
> ? ? ? ? ? ? ? ? ? ? ? ?if (!ev->status && hdev->ssp_mode > 0 &&

Not really related to the problem, but it might be a good idea to have
a check for !conn to avoid that many nested statements.


--
Luiz Augusto von Dentz
Computer Engineer