Bluetooth: Add dedicated AES instance for each SMP context
Many places have to be extra careful to not hold the hdev lock when
calling into the SMP code. This is because the SMP crypto functions use
the crypto handle that's part of the hci_dev struct. Giving the SMP
context its own handle helps simplifying the locking logic and removes
the risk for deadlocks.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
diff --git a/net/bluetooth/smp.c b/net/bluetooth/smp.c
index a389415..39ca961 100644
--- a/net/bluetooth/smp.c
+++ b/net/bluetooth/smp.c
@@ -62,6 +62,8 @@
struct smp_ltk *slave_ltk;
struct smp_irk *remote_irk;
unsigned long flags;
+
+ struct crypto_blkcipher *tfm_aes;
};
static inline void swap_buf(const u8 *src, u8 *dst, size_t len)
@@ -583,6 +585,13 @@
if (!smp)
return NULL;
+ smp->tfm_aes = crypto_alloc_blkcipher("ecb(aes)", 0, CRYPTO_ALG_ASYNC);
+ if (IS_ERR(smp->tfm_aes)) {
+ BT_ERR("Unable to create ECB crypto context");
+ kfree(smp);
+ return NULL;
+ }
+
smp->conn = conn;
conn->smp_chan = smp;
conn->hcon->smp_conn = conn;
@@ -605,6 +614,8 @@
kfree(smp->csrk);
kfree(smp->slave_csrk);
+ crypto_free_blkcipher(smp->tfm_aes);
+
/* If pairing failed clean up any keys we might have */
if (!complete) {
if (smp->ltk) {