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Commit 44f1a7ab authored by Johan Hedberg's avatar Johan Hedberg Committed by Marcel Holtmann
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Bluetooth: Use L2CAP resume callback to call smp_distribute_keys



There's no need to export the smp_distribute_keys() function since the
resume callback is called in the same scenario. This patch makes the
smp_notify_keys function private (at the same time moving it higher up
in smp.c to avoid forward declarations) and adds a resume callback for
SMP to call it from there instead.

Signed-off-by: default avatarJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: default avatarMarcel Holtmann <marcel@holtmann.org>
parent 89d2975f
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+0 −6
Original line number Diff line number Diff line
@@ -7281,12 +7281,6 @@ int l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt)

	BT_DBG("conn %p status 0x%2.2x encrypt %u", conn, status, encrypt);

	if (hcon->type == LE_LINK) {
		if (!status && encrypt)
			smp_distribute_keys(conn);
		cancel_delayed_work(&conn->security_timer);
	}

	mutex_lock(&conn->chan_lock);

	list_for_each_entry(chan, &conn->chan_l, list) {
+196 −184
Original line number Diff line number Diff line
@@ -575,6 +575,189 @@ static u8 smp_random(struct smp_chan *smp)
	return 0;
}

static void smp_notify_keys(struct l2cap_conn *conn)
{
	struct l2cap_chan *chan = conn->smp;
	struct smp_chan *smp = chan->data;
	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);
		/* Now that user space can be considered to know the
		 * identity address track the connection based on it
		 * from now on.
		 */
		bacpy(&hcon->dst, &smp->remote_irk->bdaddr);
		hcon->dst_type = smp->remote_irk->addr_type;
		l2cap_conn_update_id_addr(hcon);

		/* When receiving an indentity resolving key for
		 * a remote device that does not use a resolvable
		 * private address, just remove the key so that
		 * it is possible to use the controller white
		 * list for scanning.
		 *
		 * Userspace will have been told to not store
		 * this key at this point. So it is safe to
		 * just remove it.
		 */
		if (!bacmp(&smp->remote_irk->rpa, BDADDR_ANY)) {
			list_del(&smp->remote_irk->list);
			kfree(smp->remote_irk);
			smp->remote_irk = NULL;
		}
	}

	/* 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, 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, persistent);
	}

	if (smp->ltk) {
		smp->ltk->bdaddr_type = hcon->dst_type;
		bacpy(&smp->ltk->bdaddr, &hcon->dst);
		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, persistent);
	}
}

static int smp_distribute_keys(struct l2cap_conn *conn)
{
	struct smp_cmd_pairing *req, *rsp;
	struct l2cap_chan *chan = conn->smp;
	struct smp_chan *smp = chan->data;
	struct hci_conn *hcon = conn->hcon;
	struct hci_dev *hdev = hcon->hdev;
	__u8 *keydist;

	BT_DBG("conn %p", conn);

	if (!test_bit(HCI_CONN_LE_SMP_PEND, &hcon->flags))
		return 0;

	rsp = (void *) &smp->prsp[1];

	/* The responder sends its keys first */
	if (hcon->out && (smp->remote_key_dist & 0x07))
		return 0;

	req = (void *) &smp->preq[1];

	if (hcon->out) {
		keydist = &rsp->init_key_dist;
		*keydist &= req->init_key_dist;
	} else {
		keydist = &rsp->resp_key_dist;
		*keydist &= req->resp_key_dist;
	}

	BT_DBG("keydist 0x%x", *keydist);

	if (*keydist & SMP_DIST_ENC_KEY) {
		struct smp_cmd_encrypt_info enc;
		struct smp_cmd_master_ident ident;
		struct smp_ltk *ltk;
		u8 authenticated;
		__le16 ediv;
		__le64 rand;

		get_random_bytes(enc.ltk, sizeof(enc.ltk));
		get_random_bytes(&ediv, sizeof(ediv));
		get_random_bytes(&rand, sizeof(rand));

		smp_send_cmd(conn, SMP_CMD_ENCRYPT_INFO, sizeof(enc), &enc);

		authenticated = hcon->sec_level == BT_SECURITY_HIGH;
		ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type,
				  SMP_LTK_SLAVE, authenticated, enc.ltk,
				  smp->enc_key_size, ediv, rand);
		smp->slave_ltk = ltk;

		ident.ediv = ediv;
		ident.rand = rand;

		smp_send_cmd(conn, SMP_CMD_MASTER_IDENT, sizeof(ident), &ident);

		*keydist &= ~SMP_DIST_ENC_KEY;
	}

	if (*keydist & SMP_DIST_ID_KEY) {
		struct smp_cmd_ident_addr_info addrinfo;
		struct smp_cmd_ident_info idinfo;

		memcpy(idinfo.irk, hdev->irk, sizeof(idinfo.irk));

		smp_send_cmd(conn, SMP_CMD_IDENT_INFO, sizeof(idinfo), &idinfo);

		/* The hci_conn contains the local identity address
		 * after the connection has been established.
		 *
		 * This is true even when the connection has been
		 * established using a resolvable random address.
		 */
		bacpy(&addrinfo.bdaddr, &hcon->src);
		addrinfo.addr_type = hcon->src_type;

		smp_send_cmd(conn, SMP_CMD_IDENT_ADDR_INFO, sizeof(addrinfo),
			     &addrinfo);

		*keydist &= ~SMP_DIST_ID_KEY;
	}

	if (*keydist & SMP_DIST_SIGN) {
		struct smp_cmd_sign_info sign;
		struct smp_csrk *csrk;

		/* Generate a new random key */
		get_random_bytes(sign.csrk, sizeof(sign.csrk));

		csrk = kzalloc(sizeof(*csrk), GFP_KERNEL);
		if (csrk) {
			csrk->master = 0x00;
			memcpy(csrk->val, sign.csrk, sizeof(csrk->val));
		}
		smp->slave_csrk = csrk;

		smp_send_cmd(conn, SMP_CMD_SIGN_INFO, sizeof(sign), &sign);

		*keydist &= ~SMP_DIST_SIGN;
	}

	/* If there are still keys to be received wait for them */
	if ((smp->remote_key_dist & 0x07))
		return 0;

	clear_bit(HCI_CONN_LE_SMP_PEND, &hcon->flags);
	cancel_delayed_work_sync(&conn->security_timer);
	set_bit(SMP_FLAG_COMPLETE, &smp->flags);
	smp_notify_keys(conn);

	smp_chan_destroy(conn);

	return 0;
}

static struct smp_chan *smp_chan_create(struct l2cap_conn *conn)
{
	struct l2cap_chan *chan = conn->smp;
@@ -1294,189 +1477,6 @@ done:
	return err;
}

static void smp_notify_keys(struct l2cap_conn *conn)
{
	struct l2cap_chan *chan = conn->smp;
	struct smp_chan *smp = chan->data;
	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);
		/* Now that user space can be considered to know the
		 * identity address track the connection based on it
		 * from now on.
		 */
		bacpy(&hcon->dst, &smp->remote_irk->bdaddr);
		hcon->dst_type = smp->remote_irk->addr_type;
		l2cap_conn_update_id_addr(hcon);

		/* When receiving an indentity resolving key for
		 * a remote device that does not use a resolvable
		 * private address, just remove the key so that
		 * it is possible to use the controller white
		 * list for scanning.
		 *
		 * Userspace will have been told to not store
		 * this key at this point. So it is safe to
		 * just remove it.
		 */
		if (!bacmp(&smp->remote_irk->rpa, BDADDR_ANY)) {
			list_del(&smp->remote_irk->list);
			kfree(smp->remote_irk);
			smp->remote_irk = NULL;
		}
	}

	/* 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, 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, persistent);
	}

	if (smp->ltk) {
		smp->ltk->bdaddr_type = hcon->dst_type;
		bacpy(&smp->ltk->bdaddr, &hcon->dst);
		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, persistent);
	}
}

int smp_distribute_keys(struct l2cap_conn *conn)
{
	struct smp_cmd_pairing *req, *rsp;
	struct l2cap_chan *chan = conn->smp;
	struct smp_chan *smp = chan->data;
	struct hci_conn *hcon = conn->hcon;
	struct hci_dev *hdev = hcon->hdev;
	__u8 *keydist;

	BT_DBG("conn %p", conn);

	if (!test_bit(HCI_CONN_LE_SMP_PEND, &hcon->flags))
		return 0;

	rsp = (void *) &smp->prsp[1];

	/* The responder sends its keys first */
	if (hcon->out && (smp->remote_key_dist & 0x07))
		return 0;

	req = (void *) &smp->preq[1];

	if (hcon->out) {
		keydist = &rsp->init_key_dist;
		*keydist &= req->init_key_dist;
	} else {
		keydist = &rsp->resp_key_dist;
		*keydist &= req->resp_key_dist;
	}

	BT_DBG("keydist 0x%x", *keydist);

	if (*keydist & SMP_DIST_ENC_KEY) {
		struct smp_cmd_encrypt_info enc;
		struct smp_cmd_master_ident ident;
		struct smp_ltk *ltk;
		u8 authenticated;
		__le16 ediv;
		__le64 rand;

		get_random_bytes(enc.ltk, sizeof(enc.ltk));
		get_random_bytes(&ediv, sizeof(ediv));
		get_random_bytes(&rand, sizeof(rand));

		smp_send_cmd(conn, SMP_CMD_ENCRYPT_INFO, sizeof(enc), &enc);

		authenticated = hcon->sec_level == BT_SECURITY_HIGH;
		ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type,
				  SMP_LTK_SLAVE, authenticated, enc.ltk,
				  smp->enc_key_size, ediv, rand);
		smp->slave_ltk = ltk;

		ident.ediv = ediv;
		ident.rand = rand;

		smp_send_cmd(conn, SMP_CMD_MASTER_IDENT, sizeof(ident), &ident);

		*keydist &= ~SMP_DIST_ENC_KEY;
	}

	if (*keydist & SMP_DIST_ID_KEY) {
		struct smp_cmd_ident_addr_info addrinfo;
		struct smp_cmd_ident_info idinfo;

		memcpy(idinfo.irk, hdev->irk, sizeof(idinfo.irk));

		smp_send_cmd(conn, SMP_CMD_IDENT_INFO, sizeof(idinfo), &idinfo);

		/* The hci_conn contains the local identity address
		 * after the connection has been established.
		 *
		 * This is true even when the connection has been
		 * established using a resolvable random address.
		 */
		bacpy(&addrinfo.bdaddr, &hcon->src);
		addrinfo.addr_type = hcon->src_type;

		smp_send_cmd(conn, SMP_CMD_IDENT_ADDR_INFO, sizeof(addrinfo),
			     &addrinfo);

		*keydist &= ~SMP_DIST_ID_KEY;
	}

	if (*keydist & SMP_DIST_SIGN) {
		struct smp_cmd_sign_info sign;
		struct smp_csrk *csrk;

		/* Generate a new random key */
		get_random_bytes(sign.csrk, sizeof(sign.csrk));

		csrk = kzalloc(sizeof(*csrk), GFP_KERNEL);
		if (csrk) {
			csrk->master = 0x00;
			memcpy(csrk->val, sign.csrk, sizeof(csrk->val));
		}
		smp->slave_csrk = csrk;

		smp_send_cmd(conn, SMP_CMD_SIGN_INFO, sizeof(sign), &sign);

		*keydist &= ~SMP_DIST_SIGN;
	}

	/* If there are still keys to be received wait for them */
	if ((smp->remote_key_dist & 0x07))
		return 0;

	clear_bit(HCI_CONN_LE_SMP_PEND, &hcon->flags);
	cancel_delayed_work_sync(&conn->security_timer);
	set_bit(SMP_FLAG_COMPLETE, &smp->flags);
	smp_notify_keys(conn);

	smp_chan_destroy(conn);

	return 0;
}

static void smp_teardown_cb(struct l2cap_chan *chan, int err)
{
	struct l2cap_conn *conn = chan->conn;
@@ -1492,6 +1492,18 @@ static void smp_teardown_cb(struct l2cap_chan *chan, int err)
	l2cap_chan_put(chan);
}

static void smp_resume_cb(struct l2cap_chan *chan)
{
	struct l2cap_conn *conn = chan->conn;
	struct hci_conn *hcon = conn->hcon;

	BT_DBG("chan %p", chan);

	if (test_bit(HCI_CONN_ENCRYPT, &hcon->flags))
		smp_distribute_keys(conn);
	cancel_delayed_work(&conn->security_timer);
}

static void smp_ready_cb(struct l2cap_chan *chan)
{
	struct l2cap_conn *conn = chan->conn;
@@ -1524,13 +1536,13 @@ static const struct l2cap_ops smp_chan_ops = {
	.recv			= smp_recv_cb,
	.alloc_skb		= smp_alloc_skb_cb,
	.teardown		= smp_teardown_cb,
	.resume			= smp_resume_cb,

	.new_connection		= l2cap_chan_no_new_connection,
	.state_change		= l2cap_chan_no_state_change,
	.close			= l2cap_chan_no_close,
	.defer			= l2cap_chan_no_defer,
	.suspend		= l2cap_chan_no_suspend,
	.resume			= l2cap_chan_no_resume,
	.set_shutdown		= l2cap_chan_no_set_shutdown,
	.get_sndtimeo		= l2cap_chan_no_get_sndtimeo,
	.memcpy_fromiovec	= l2cap_chan_no_memcpy_fromiovec,
+0 −1
Original line number Diff line number Diff line
@@ -126,7 +126,6 @@ enum {
/* SMP Commands */
bool smp_sufficient_security(struct hci_conn *hcon, u8 sec_level);
int smp_conn_security(struct hci_conn *hcon, __u8 sec_level);
int smp_distribute_keys(struct l2cap_conn *conn);
int smp_user_confirm_reply(struct hci_conn *conn, u16 mgmt_op, __le32 passkey);

void smp_chan_destroy(struct l2cap_conn *conn);