| Message ID | 20200520212015.626026-1-luiz.dentz@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Delegated to: | Marcel Holtmann |
| Headers | show |
| Series | [v2,1/2] Bluetooth: Disconnect if E0 is used for Level 4 | expand |
Hi Marcel, On Wed, May 20, 2020 at 2:20 PM Luiz Augusto von Dentz <luiz.dentz@gmail.com> wrote: > > From: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> > > E0 is not allowed with Level 4: > > BLUETOOTH CORE SPECIFICATION Version 5.2 | Vol 3, Part C page 1319: > > '128-bit equivalent strength for link and encryption keys > required using FIPS approved algorithms (E0 not allowed, > SAFER+ not allowed, and P-192 not allowed; encryption key > not shortened' > > SC enabled: > > > HCI Event: Read Remote Extended Features (0x23) plen 13 > Status: Success (0x00) > Handle: 256 > Page: 1/2 > Features: 0x0b 0x00 0x00 0x00 0x00 0x00 0x00 0x00 > Secure Simple Pairing (Host Support) > LE Supported (Host) > Secure Connections (Host Support) > > HCI Event: Encryption Change (0x08) plen 4 > Status: Success (0x00) > Handle: 256 > Encryption: Enabled with AES-CCM (0x02) > > SC disabled: > > > HCI Event: Read Remote Extended Features (0x23) plen 13 > Status: Success (0x00) > Handle: 256 > Page: 1/2 > Features: 0x03 0x00 0x00 0x00 0x00 0x00 0x00 0x00 > Secure Simple Pairing (Host Support) > LE Supported (Host) > > HCI Event: Encryption Change (0x08) plen 4 > Status: Success (0x00) > Handle: 256 > Encryption: Enabled with E0 (0x01) > [May 8 20:23] Bluetooth: hci0: Invalid security: expect AES but E0 was used > < HCI Command: Disconnect (0x01|0x0006) plen 3 > Handle: 256 > Reason: Authentication Failure (0x05) > > Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> > --- > include/net/bluetooth/hci_core.h | 10 ++++++---- > net/bluetooth/hci_conn.c | 17 +++++++++++++++++ > net/bluetooth/hci_event.c | 20 ++++++++------------ > 3 files changed, 31 insertions(+), 16 deletions(-) > > diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h > index cdd4f1db8670..c69309ffd40a 100644 > --- a/include/net/bluetooth/hci_core.h > +++ b/include/net/bluetooth/hci_core.h > @@ -1402,11 +1402,13 @@ static inline void hci_encrypt_cfm(struct hci_conn *conn, __u8 status) > else > encrypt = 0x01; > > - if (conn->sec_level == BT_SECURITY_SDP) > - conn->sec_level = BT_SECURITY_LOW; > + if (!status) { > + if (conn->sec_level == BT_SECURITY_SDP) > + conn->sec_level = BT_SECURITY_LOW; > > - if (conn->pending_sec_level > conn->sec_level) > - conn->sec_level = conn->pending_sec_level; > + if (conn->pending_sec_level > conn->sec_level) > + conn->sec_level = conn->pending_sec_level; > + } > > mutex_lock(&hci_cb_list_lock); > list_for_each_entry(cb, &hci_cb_list, list) { > diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c > index 307800fd18e6..b99b5c6de55a 100644 > --- a/net/bluetooth/hci_conn.c > +++ b/net/bluetooth/hci_conn.c > @@ -1323,6 +1323,23 @@ int hci_conn_check_link_mode(struct hci_conn *conn) > return 0; > } > > + /* AES encryption is required for Level 4: > + * > + * BLUETOOTH CORE SPECIFICATION Version 5.2 | Vol 3, Part C > + * page 1319: > + * > + * 128-bit equivalent strength for link and encryption keys > + * required using FIPS approved algorithms (E0 not allowed, > + * SAFER+ not allowed, and P-192 not allowed; encryption key > + * not shortened) > + */ > + if (conn->sec_level == BT_SECURITY_FIPS && > + !test_bit(HCI_CONN_AES_CCM, &conn->flags)) { > + bt_dev_err(conn->hdev, > + "Invalid security: Missing AES-CCM usage"); > + return 0; > + } > + > if (hci_conn_ssp_enabled(conn) && > !test_bit(HCI_CONN_ENCRYPT, &conn->flags)) > return 0; > diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c > index cfeaee347db3..d6a1e2450696 100644 > --- a/net/bluetooth/hci_event.c > +++ b/net/bluetooth/hci_event.c > @@ -3065,27 +3065,23 @@ static void hci_encrypt_change_evt(struct hci_dev *hdev, struct sk_buff *skb) > > clear_bit(HCI_CONN_ENCRYPT_PEND, &conn->flags); > > + /* Check link security requirements are met */ > + if (!hci_conn_check_link_mode(conn)) > + ev->status = HCI_ERROR_AUTH_FAILURE; > + > if (ev->status && conn->state == BT_CONNECTED) { > if (ev->status == HCI_ERROR_PIN_OR_KEY_MISSING) > set_bit(HCI_CONN_AUTH_FAILURE, &conn->flags); > > + /* Notify upper layers so they can cleanup before > + * disconnecting. > + */ > + hci_encrypt_cfm(conn, ev->status); > hci_disconnect(conn, HCI_ERROR_AUTH_FAILURE); > hci_conn_drop(conn); > goto unlock; > } > > - /* In Secure Connections Only mode, do not allow any connections > - * that are not encrypted with AES-CCM using a P-256 authenticated > - * combination key. > - */ > - if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && > - (!test_bit(HCI_CONN_AES_CCM, &conn->flags) || > - conn->key_type != HCI_LK_AUTH_COMBINATION_P256)) { > - hci_connect_cfm(conn, HCI_ERROR_AUTH_FAILURE); > - hci_conn_drop(conn); > - goto unlock; > - } > - > /* Try reading the encryption key size for encrypted ACL links */ > if (!ev->status && ev->encrypt && conn->type == ACL_LINK) { > struct hci_cp_read_enc_key_size cp; > -- > 2.25.3 Looks like we had left this behind.
Hi Luiz, > E0 is not allowed with Level 4: > > BLUETOOTH CORE SPECIFICATION Version 5.2 | Vol 3, Part C page 1319: > > '128-bit equivalent strength for link and encryption keys > required using FIPS approved algorithms (E0 not allowed, > SAFER+ not allowed, and P-192 not allowed; encryption key > not shortened' > > SC enabled: > >> HCI Event: Read Remote Extended Features (0x23) plen 13 > Status: Success (0x00) > Handle: 256 > Page: 1/2 > Features: 0x0b 0x00 0x00 0x00 0x00 0x00 0x00 0x00 > Secure Simple Pairing (Host Support) > LE Supported (Host) > Secure Connections (Host Support) >> HCI Event: Encryption Change (0x08) plen 4 > Status: Success (0x00) > Handle: 256 > Encryption: Enabled with AES-CCM (0x02) > > SC disabled: > >> HCI Event: Read Remote Extended Features (0x23) plen 13 > Status: Success (0x00) > Handle: 256 > Page: 1/2 > Features: 0x03 0x00 0x00 0x00 0x00 0x00 0x00 0x00 > Secure Simple Pairing (Host Support) > LE Supported (Host) >> HCI Event: Encryption Change (0x08) plen 4 > Status: Success (0x00) > Handle: 256 > Encryption: Enabled with E0 (0x01) > [May 8 20:23] Bluetooth: hci0: Invalid security: expect AES but E0 was used > < HCI Command: Disconnect (0x01|0x0006) plen 3 > Handle: 256 > Reason: Authentication Failure (0x05) > > Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> > --- > include/net/bluetooth/hci_core.h | 10 ++++++---- > net/bluetooth/hci_conn.c | 17 +++++++++++++++++ > net/bluetooth/hci_event.c | 20 ++++++++------------ > 3 files changed, 31 insertions(+), 16 deletions(-) patch has been applied to bluetooth-next tree. Regards Marcel
diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h index cdd4f1db8670..c69309ffd40a 100644 --- a/include/net/bluetooth/hci_core.h +++ b/include/net/bluetooth/hci_core.h @@ -1402,11 +1402,13 @@ static inline void hci_encrypt_cfm(struct hci_conn *conn, __u8 status) else encrypt = 0x01; - if (conn->sec_level == BT_SECURITY_SDP) - conn->sec_level = BT_SECURITY_LOW; + if (!status) { + if (conn->sec_level == BT_SECURITY_SDP) + conn->sec_level = BT_SECURITY_LOW; - if (conn->pending_sec_level > conn->sec_level) - conn->sec_level = conn->pending_sec_level; + if (conn->pending_sec_level > conn->sec_level) + conn->sec_level = conn->pending_sec_level; + } mutex_lock(&hci_cb_list_lock); list_for_each_entry(cb, &hci_cb_list, list) { diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c index 307800fd18e6..b99b5c6de55a 100644 --- a/net/bluetooth/hci_conn.c +++ b/net/bluetooth/hci_conn.c @@ -1323,6 +1323,23 @@ int hci_conn_check_link_mode(struct hci_conn *conn) return 0; } + /* AES encryption is required for Level 4: + * + * BLUETOOTH CORE SPECIFICATION Version 5.2 | Vol 3, Part C + * page 1319: + * + * 128-bit equivalent strength for link and encryption keys + * required using FIPS approved algorithms (E0 not allowed, + * SAFER+ not allowed, and P-192 not allowed; encryption key + * not shortened) + */ + if (conn->sec_level == BT_SECURITY_FIPS && + !test_bit(HCI_CONN_AES_CCM, &conn->flags)) { + bt_dev_err(conn->hdev, + "Invalid security: Missing AES-CCM usage"); + return 0; + } + if (hci_conn_ssp_enabled(conn) && !test_bit(HCI_CONN_ENCRYPT, &conn->flags)) return 0; diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c index cfeaee347db3..d6a1e2450696 100644 --- a/net/bluetooth/hci_event.c +++ b/net/bluetooth/hci_event.c @@ -3065,27 +3065,23 @@ static void hci_encrypt_change_evt(struct hci_dev *hdev, struct sk_buff *skb) clear_bit(HCI_CONN_ENCRYPT_PEND, &conn->flags); + /* Check link security requirements are met */ + if (!hci_conn_check_link_mode(conn)) + ev->status = HCI_ERROR_AUTH_FAILURE; + if (ev->status && conn->state == BT_CONNECTED) { if (ev->status == HCI_ERROR_PIN_OR_KEY_MISSING) set_bit(HCI_CONN_AUTH_FAILURE, &conn->flags); + /* Notify upper layers so they can cleanup before + * disconnecting. + */ + hci_encrypt_cfm(conn, ev->status); hci_disconnect(conn, HCI_ERROR_AUTH_FAILURE); hci_conn_drop(conn); goto unlock; } - /* In Secure Connections Only mode, do not allow any connections - * that are not encrypted with AES-CCM using a P-256 authenticated - * combination key. - */ - if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && - (!test_bit(HCI_CONN_AES_CCM, &conn->flags) || - conn->key_type != HCI_LK_AUTH_COMBINATION_P256)) { - hci_connect_cfm(conn, HCI_ERROR_AUTH_FAILURE); - hci_conn_drop(conn); - goto unlock; - } - /* Try reading the encryption key size for encrypted ACL links */ if (!ev->status && ev->encrypt && conn->type == ACL_LINK) { struct hci_cp_read_enc_key_size cp;