Bluetooth: Add support for AES-CMAC hash for security manager device

The security manager device will require the use of AES-CMAC hash for
out-of-band data generation. This patch makes sure it is correctly
set up and available.

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

diff --git a/net/bluetooth/smp.c b/net/bluetooth/smp.c
index 952ba63..12e9c83 100644 (file)
--- a/net/bluetooth/smp.c
+++ b/net/bluetooth/smp.c
@@ -75,6 +75,7 @@ enum {
 
 struct smp_dev {
        struct crypto_blkcipher *tfm_aes;
+       struct crypto_hash      *tfm_cmac;
 };
 
 struct smp_chan {
@@ -2936,6 +2937,7 @@ 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;
+       struct crypto_hash *tfm_cmac;
 
        if (cid == L2CAP_CID_SMP_BREDR) {
                smp = NULL;
@@ -2953,12 +2955,22 @@ static struct l2cap_chan *smp_add_cid(struct hci_dev *hdev, u16 cid)
                return ERR_CAST(tfm_aes);
        }
 
+       tfm_cmac = crypto_alloc_hash("cmac(aes)", 0, CRYPTO_ALG_ASYNC);
+       if (IS_ERR(tfm_cmac)) {
+               BT_ERR("Unable to create CMAC crypto context");
+               crypto_free_blkcipher(tfm_aes);
+               kzfree(smp);
+               return ERR_CAST(tfm_cmac);
+       }
+
        smp->tfm_aes = tfm_aes;
+       smp->tfm_cmac = tfm_cmac;
 
 create_chan:
        chan = l2cap_chan_create();
        if (!chan) {
                crypto_free_blkcipher(smp->tfm_aes);
+               crypto_free_hash(smp->tfm_cmac);
                kzfree(smp);
                return ERR_PTR(-ENOMEM);
        }
@@ -3005,6 +3017,8 @@ static void smp_del_chan(struct l2cap_chan *chan)
                chan->data = NULL;
                if (smp->tfm_aes)
                        crypto_free_blkcipher(smp->tfm_aes);
+               if (smp->tfm_cmac)
+                       crypto_free_hash(smp->tfm_cmac);
                kzfree(smp);
        }