Commit fd349c02 authored by Johan Hedberg's avatar Johan Hedberg Committed by Marcel Holtmann
Browse files

Bluetooth: Enable support for remote IRK distribution 



This patch does the necessary changes to request the remote device to
distribute its IRK to us during the SMP pairing procedure. This includes
setting the right key distribution values in the pairing
request/response and handling of the two related SMP PDUs, i.e. Identity
Information and Identity Address Information.

Signed-off-by: default avatarJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: default avatarMarcel Holtmann <marcel@holtmann.org>
parent 41edf160

net/bluetooth/smp.c

+73 −7
Original line number Diff line number Diff line
@@ -249,31 +249,42 @@ static void build_pairing_cmd(struct l2cap_conn *conn, 
			      struct smp_cmd_pairing *req,

			      struct smp_cmd_pairing *rsp, __u8 authreq)

{

	u8 dist_keys = 0;

	struct smp_chan *smp = conn->smp_chan;

	struct hci_conn *hcon = conn->hcon;

	struct hci_dev *hdev = hcon->hdev;

	u8 local_dist = 0, remote_dist = 0;



	if (test_bit(HCI_PAIRABLE, &conn->hcon->hdev->dev_flags)) {

		dist_keys = SMP_DIST_ENC_KEY;

		local_dist = SMP_DIST_ENC_KEY;

		remote_dist = SMP_DIST_ENC_KEY;

		authreq |= SMP_AUTH_BONDING;

	} else {

		authreq &= ~SMP_AUTH_BONDING;

	}



	if (test_bit(HCI_RPA_RESOLVING, &hdev->dev_flags))

		remote_dist |= SMP_DIST_ID_KEY;



	if (rsp == NULL) {

		req->io_capability = conn->hcon->io_capability;

		req->oob_flag = SMP_OOB_NOT_PRESENT;

		req->max_key_size = SMP_MAX_ENC_KEY_SIZE;

		req->init_key_dist = dist_keys;

		req->resp_key_dist = dist_keys;

		req->init_key_dist = local_dist;

		req->resp_key_dist = remote_dist;

		req->auth_req = (authreq & AUTH_REQ_MASK);



		smp->remote_key_dist = remote_dist;

		return;

	}



	rsp->io_capability = conn->hcon->io_capability;

	rsp->oob_flag = SMP_OOB_NOT_PRESENT;

	rsp->max_key_size = SMP_MAX_ENC_KEY_SIZE;

	rsp->init_key_dist = req->init_key_dist & dist_keys;

	rsp->resp_key_dist = req->resp_key_dist & dist_keys;

	rsp->init_key_dist = req->init_key_dist & remote_dist;

	rsp->resp_key_dist = req->resp_key_dist & local_dist;

	rsp->auth_req = (authreq & AUTH_REQ_MASK);



	smp->remote_key_dist = rsp->init_key_dist;

}



static u8 check_enc_key_size(struct l2cap_conn *conn, __u8 max_key_size)
@@ -907,12 +918,61 @@ static int smp_cmd_master_ident(struct l2cap_conn *conn, struct sk_buff *skb) 
	hci_add_ltk(hdev, &hcon->dst, hcon->dst_type, HCI_SMP_LTK, 1,

		    authenticated, smp->tk, smp->enc_key_size,

		    rp->ediv, rp->rand);

	if (!(smp->remote_key_dist & SMP_DIST_ID_KEY))

		smp_distribute_keys(conn, 1);

	hci_dev_unlock(hdev);



	return 0;

}



static int smp_cmd_ident_info(struct l2cap_conn *conn, struct sk_buff *skb)

{

	struct smp_cmd_ident_info *info = (void *) skb->data;

	struct smp_chan *smp = conn->smp_chan;



	BT_DBG("");



	if (skb->len < sizeof(*info))

		return SMP_UNSPECIFIED;



	skb_pull(skb, sizeof(*info));



	memcpy(smp->irk, info->irk, 16);



	return 0;

}



static int smp_cmd_ident_addr_info(struct l2cap_conn *conn,

				   struct sk_buff *skb)

{

	struct smp_cmd_ident_addr_info *info = (void *) skb->data;

	struct smp_chan *smp = conn->smp_chan;

	struct hci_conn *hcon = conn->hcon;

	bdaddr_t rpa;



	BT_DBG("");



	if (skb->len < sizeof(*info))

		return SMP_UNSPECIFIED;



	skb_pull(skb, sizeof(*info));



	bacpy(&smp->id_addr, &info->bdaddr);

	smp->id_addr_type = info->addr_type;



	if (hci_bdaddr_is_rpa(&hcon->dst, hcon->dst_type))

		bacpy(&rpa, &hcon->dst);

	else

		bacpy(&rpa, BDADDR_ANY);



	hci_add_irk(conn->hcon->hdev, &smp->id_addr, smp->id_addr_type,

		    smp->irk, &rpa);



	smp_distribute_keys(conn, 1);



	return 0;

}



int smp_sig_channel(struct l2cap_conn *conn, struct sk_buff *skb)

{

	struct hci_conn *hcon = conn->hcon;
@@ -987,7 +1047,13 @@ int smp_sig_channel(struct l2cap_conn *conn, struct sk_buff *skb) 
		break;



	case SMP_CMD_IDENT_INFO:

		reason = smp_cmd_ident_info(conn, skb);

		break;



	case SMP_CMD_IDENT_ADDR_INFO:

		reason = smp_cmd_ident_addr_info(conn, skb);

		break;



	case SMP_CMD_SIGN_INFO:

		/* Just ignored */

		reason = 0;

net/bluetooth/smp.h

+4 −0
Original line number Diff line number Diff line
@@ -128,6 +128,10 @@ struct smp_chan { 
	u8		pcnf[16]; /* SMP Pairing Confirm */

	u8		tk[16]; /* SMP Temporary Key */

	u8		enc_key_size;

	u8		remote_key_dist;

	bdaddr_t	id_addr;

	u8		id_addr_type;

	u8		irk[16];

	unsigned long	smp_flags;

	struct crypto_blkcipher	*tfm;

	struct work_struct confirm;

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