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: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>

1 files changed, 31 insertions, 16 deletions

diff --git a/net/bluetooth/smp.c b/net/bluetooth/smp.c
index a2be6fcc3c51..952ba6376e1c 100644
--- a/net/bluetooth/smp.c
+++ b/net/bluetooth/smp.c
@@ -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 crypto_blkcipher *tfm_aes;
+        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 @@ create_chan:
 
 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);