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Commit 88a479d9 authored by Marcel Holtmann's avatar Marcel Holtmann Committed by Johan Hedberg
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Bluetooth: Create SMP device structure for local crypto context 



Every Bluetooth Low Energy controller requires a local crypto context
to handle the resolvable private addresses. At the moment this is just
a single crypto context, but for out-of-band data generation it will
require an additional. To facility this, create a struct smp_dev that
will hold all the extra information. This patch is just the refactoring
in preparation for future changes.

Signed-off-by: default avatarMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: default avatarJohan Hedberg <johan.hedberg@intel.com>
parent 276812ec

net/bluetooth/smp.c

+31 −16
Original line number Diff line number Diff line
@@ -73,6 +73,10 @@ enum { 
	SMP_FLAG_OOB,

};



struct smp_dev {

	struct crypto_blkcipher	*tfm_aes;

};



struct smp_chan {

	struct l2cap_conn	*conn;

	struct delayed_work	security_timer;
@@ -478,18 +482,18 @@ bool smp_irk_matches(struct hci_dev *hdev, const u8 irk[16], 
		     const bdaddr_t *bdaddr)

{

	struct l2cap_chan *chan = hdev->smp_data;

	struct crypto_blkcipher *tfm;

	struct smp_dev *smp;

	u8 hash[3];

	int err;



	if (!chan || !chan->data)

		return false;



	tfm = chan->data;

	smp = chan->data;



	BT_DBG("RPA %pMR IRK %*phN", bdaddr, 16, irk);



	err = smp_ah(tfm, irk, &bdaddr->b[3], hash);

	err = smp_ah(smp->tfm_aes, irk, &bdaddr->b[3], hash);

	if (err)

		return false;
@@ -499,20 +503,20 @@ bool smp_irk_matches(struct hci_dev *hdev, const u8 irk[16], 
int smp_generate_rpa(struct hci_dev *hdev, const u8 irk[16], bdaddr_t *rpa)

{

	struct l2cap_chan *chan = hdev->smp_data;

	struct crypto_blkcipher *tfm;

	struct smp_dev *smp;

	int err;



	if (!chan || !chan->data)

		return -EOPNOTSUPP;



	tfm = chan->data;

	smp = chan->data;



	get_random_bytes(&rpa->b[3], 3);



	rpa->b[5] &= 0x3f;	/* Clear two most significant bits */

	rpa->b[5] |= 0x40;	/* Set second most significant bit */



	err = smp_ah(tfm, irk, &rpa->b[3], rpa->b);

	err = smp_ah(smp->tfm_aes, irk, &rpa->b[3], rpa->b);

	if (err < 0)

		return err;
@@ -2930,27 +2934,36 @@ static const struct l2cap_ops smp_root_chan_ops = { 
static struct l2cap_chan *smp_add_cid(struct hci_dev *hdev, u16 cid)

{

	struct l2cap_chan *chan;

	struct smp_dev *smp;

	struct crypto_blkcipher *tfm_aes;



	if (cid == L2CAP_CID_SMP_BREDR) {

		tfm_aes = NULL;

		smp = NULL;

		goto create_chan;

	}



	tfm_aes = crypto_alloc_blkcipher("ecb(aes)", 0, 0);

	smp = kzalloc(sizeof(*smp), GFP_KERNEL);

	if (!smp)

		return ERR_PTR(-ENOMEM);



	tfm_aes = crypto_alloc_blkcipher("ecb(aes)", 0, CRYPTO_ALG_ASYNC);

	if (IS_ERR(tfm_aes)) {

		BT_ERR("Unable to create crypto context");

		BT_ERR("Unable to create ECB crypto context");

		kzfree(smp);

		return ERR_CAST(tfm_aes);

	}



	smp->tfm_aes = tfm_aes;



create_chan:

	chan = l2cap_chan_create();

	if (!chan) {

		crypto_free_blkcipher(tfm_aes);

		crypto_free_blkcipher(smp->tfm_aes);

		kzfree(smp);

		return ERR_PTR(-ENOMEM);

	}



	chan->data = tfm_aes;

	chan->data = smp;



	l2cap_add_scid(chan, cid);
@@ -2983,14 +2996,16 @@ static struct l2cap_chan *smp_add_cid(struct hci_dev *hdev, u16 cid) 


static void smp_del_chan(struct l2cap_chan *chan)

{

	struct crypto_blkcipher	*tfm_aes;

	struct smp_dev *smp;



	BT_DBG("chan %p", chan);



	tfm_aes = chan->data;

	if (tfm_aes) {

	smp = chan->data;

	if (smp) {

		chan->data = NULL;

		crypto_free_blkcipher(tfm_aes);

		if (smp->tfm_aes)

			crypto_free_blkcipher(smp->tfm_aes);

		kzfree(smp);

	}



	l2cap_chan_put(chan);