From 53ac6ab612456a13bf0f6bad89c1503616e4de3b Mon Sep 17 00:00:00 2001 From: Marcel Holtmann Date: Sun, 9 Mar 2014 23:38:42 -0700 Subject: [PATCH] Bluetooth: Make LTK and CSRK only persisent when bonding In case the pairable option has been disabled, the pairing procedure does not create keys for bonding. This means that these generated keys should not be stored persistently. For LTK and CSRK this is important to tell userspace to not store these new keys. They will be available for the lifetime of the device, but after the next power cycle they should not be used anymore. Inform userspace to actually store the keys persistently only if both sides request bonding. Signed-off-by: Marcel Holtmann Signed-off-by: Johan Hedberg --- include/net/bluetooth/hci_core.h | 5 +++-- net/bluetooth/mgmt.c | 9 +++++---- net/bluetooth/smp.c | 16 ++++++++++++---- 3 files changed, 20 insertions(+), 10 deletions(-) diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h index e869884f..b8cc39a 100644 --- a/include/net/bluetooth/hci_core.h +++ b/include/net/bluetooth/hci_core.h @@ -1270,9 +1270,10 @@ void mgmt_remote_name(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 link_type, void mgmt_discovering(struct hci_dev *hdev, u8 discovering); int mgmt_device_blocked(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 type); int mgmt_device_unblocked(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 type); -void mgmt_new_ltk(struct hci_dev *hdev, struct smp_ltk *key); +void mgmt_new_ltk(struct hci_dev *hdev, struct smp_ltk *key, bool persistent); void mgmt_new_irk(struct hci_dev *hdev, struct smp_irk *irk); -void mgmt_new_csrk(struct hci_dev *hdev, struct smp_csrk *csrk); +void mgmt_new_csrk(struct hci_dev *hdev, struct smp_csrk *csrk, + bool persistent); void mgmt_reenable_advertising(struct hci_dev *hdev); void mgmt_smp_complete(struct hci_conn *conn, bool complete); diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c index 9c77889..fbcf9d4 100644 --- a/net/bluetooth/mgmt.c +++ b/net/bluetooth/mgmt.c @@ -5005,7 +5005,7 @@ void mgmt_new_link_key(struct hci_dev *hdev, struct link_key *key, mgmt_event(MGMT_EV_NEW_LINK_KEY, hdev, &ev, sizeof(ev), NULL); } -void mgmt_new_ltk(struct hci_dev *hdev, struct smp_ltk *key) +void mgmt_new_ltk(struct hci_dev *hdev, struct smp_ltk *key, bool persistent) { struct mgmt_ev_new_long_term_key ev; @@ -5026,7 +5026,7 @@ void mgmt_new_ltk(struct hci_dev *hdev, struct smp_ltk *key) (key->bdaddr.b[5] & 0xc0) != 0xc0) ev.store_hint = 0x00; else - ev.store_hint = 0x01; + ev.store_hint = persistent; bacpy(&ev.key.addr.bdaddr, &key->bdaddr); ev.key.addr.type = link_to_bdaddr(LE_LINK, key->bdaddr_type); @@ -5073,7 +5073,8 @@ void mgmt_new_irk(struct hci_dev *hdev, struct smp_irk *irk) mgmt_event(MGMT_EV_NEW_IRK, hdev, &ev, sizeof(ev), NULL); } -void mgmt_new_csrk(struct hci_dev *hdev, struct smp_csrk *csrk) +void mgmt_new_csrk(struct hci_dev *hdev, struct smp_csrk *csrk, + bool persistent) { struct mgmt_ev_new_csrk ev; @@ -5092,7 +5093,7 @@ void mgmt_new_csrk(struct hci_dev *hdev, struct smp_csrk *csrk) (csrk->bdaddr.b[5] & 0xc0) != 0xc0) ev.store_hint = 0x00; else - ev.store_hint = 0x01; + ev.store_hint = persistent; bacpy(&ev.key.addr.bdaddr, &csrk->bdaddr); ev.key.addr.type = link_to_bdaddr(LE_LINK, csrk->bdaddr_type); diff --git a/net/bluetooth/smp.c b/net/bluetooth/smp.c index fc65259..7f25dda 100644 --- a/net/bluetooth/smp.c +++ b/net/bluetooth/smp.c @@ -1209,32 +1209,40 @@ static void smp_notify_keys(struct l2cap_conn *conn) struct smp_chan *smp = conn->smp_chan; struct hci_conn *hcon = conn->hcon; struct hci_dev *hdev = hcon->hdev; + struct smp_cmd_pairing *req = (void *) &smp->preq[1]; + struct smp_cmd_pairing *rsp = (void *) &smp->prsp[1]; + bool persistent; if (smp->remote_irk) mgmt_new_irk(hdev, smp->remote_irk); + /* The LTKs and CSRKs should be persistent only if both sides + * had the bonding bit set in their authentication requests. + */ + persistent = !!((req->auth_req & rsp->auth_req) & SMP_AUTH_BONDING); + if (smp->csrk) { smp->csrk->bdaddr_type = hcon->dst_type; bacpy(&smp->csrk->bdaddr, &hcon->dst); - mgmt_new_csrk(hdev, smp->csrk); + mgmt_new_csrk(hdev, smp->csrk, persistent); } if (smp->slave_csrk) { smp->slave_csrk->bdaddr_type = hcon->dst_type; bacpy(&smp->slave_csrk->bdaddr, &hcon->dst); - mgmt_new_csrk(hdev, smp->slave_csrk); + mgmt_new_csrk(hdev, smp->slave_csrk, persistent); } if (smp->ltk) { smp->ltk->bdaddr_type = hcon->dst_type; bacpy(&smp->ltk->bdaddr, &hcon->dst); - mgmt_new_ltk(hdev, smp->ltk); + mgmt_new_ltk(hdev, smp->ltk, persistent); } if (smp->slave_ltk) { smp->slave_ltk->bdaddr_type = hcon->dst_type; bacpy(&smp->slave_ltk->bdaddr, &hcon->dst); - mgmt_new_ltk(hdev, smp->slave_ltk); + mgmt_new_ltk(hdev, smp->slave_ltk, persistent); } } -- 2.7.4