Bluetooth: Add support for storing the key size
In some cases it will be useful having the key size used for
encrypting the link. For example, some profiles may restrict
some operations depending on the key length.
The key size is stored in the key that is passed to userspace
using the pin_length field in the key structure.
For now this field is only valid for LE controllers. 3.0+HS
controllers define the Read Encryption Key Size command, this
field is intended for storing the value returned by that
command.
Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@openbossa.org>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index 4ff530e..c41e275 100644
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -261,6 +261,7 @@
__u8 sec_level;
__u8 pending_sec_level;
__u8 pin_length;
+ __u8 enc_key_size;
__u8 io_capability;
__u8 power_save;
__u16 disc_timeout;
@@ -556,7 +557,7 @@
struct link_key *hci_find_link_key_type(struct hci_dev *hdev,
bdaddr_t *bdaddr, u8 type);
int hci_add_ltk(struct hci_dev *hdev, int new_key, bdaddr_t *bdaddr,
- __le16 ediv, u8 rand[8], u8 ltk[16]);
+ u8 key_size, __le16 ediv, u8 rand[8], u8 ltk[16]);
int hci_remove_link_key(struct hci_dev *hdev, bdaddr_t *bdaddr);
int hci_remote_oob_data_clear(struct hci_dev *hdev);
diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index 4885914..908fcd3 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -1149,7 +1149,7 @@
}
int hci_add_ltk(struct hci_dev *hdev, int new_key, bdaddr_t *bdaddr,
- __le16 ediv, u8 rand[8], u8 ltk[16])
+ u8 key_size, __le16 ediv, u8 rand[8], u8 ltk[16])
{
struct link_key *key, *old_key;
struct key_master_id *id;
@@ -1174,6 +1174,7 @@
bacpy(&key->bdaddr, bdaddr);
memcpy(key->val, ltk, sizeof(key->val));
key->type = HCI_LK_SMP_LTK;
+ key->pin_len = key_size;
id = (void *) &key->data;
id->ediv = ediv;
diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index ca5ff6e..a40170e 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -2876,6 +2876,7 @@
memcpy(cp.ltk, ltk->val, sizeof(ltk->val));
cp.handle = cpu_to_le16(conn->handle);
+ conn->pin_length = ltk->pin_len;
hci_send_cmd(hdev, HCI_OP_LE_LTK_REPLY, sizeof(cp), &cp);
diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
index f424d6a..53e109e 100644
--- a/net/bluetooth/mgmt.c
+++ b/net/bluetooth/mgmt.c
@@ -956,8 +956,8 @@
if (key->dlen != sizeof(struct key_master_id))
continue;
- hci_add_ltk(hdev, 0, &key->bdaddr, id->ediv,
- id->rand, key->val);
+ hci_add_ltk(hdev, 0, &key->bdaddr, key->pin_len,
+ id->ediv, id->rand, key->val);
continue;
}
diff --git a/net/bluetooth/smp.c b/net/bluetooth/smp.c
index a8b971b..391888b 100644
--- a/net/bluetooth/smp.c
+++ b/net/bluetooth/smp.c
@@ -401,6 +401,7 @@
SMP_MAX_ENC_KEY_SIZE - conn->smp_key_size);
hci_le_start_enc(hcon, ediv, rand, stk);
+ hcon->enc_key_size = conn->smp_key_size;
} else {
u8 stk[16], r[16], rand[8];
__le16 ediv;
@@ -417,7 +418,8 @@
memset(stk + conn->smp_key_size, 0,
SMP_MAX_ENC_KEY_SIZE - conn->smp_key_size);
- hci_add_ltk(conn->hcon->hdev, 0, conn->dst, ediv, rand, stk);
+ hci_add_ltk(conn->hcon->hdev, 0, conn->dst, conn->smp_key_size,
+ ediv, rand, stk);
}
return 0;
@@ -487,6 +489,8 @@
hci_le_start_enc(hcon, master->ediv, master->rand,
key->val);
+ hcon->enc_key_size = key->pin_len;
+
goto done;
}
@@ -528,8 +532,8 @@
skb_pull(skb, sizeof(*rp));
- hci_add_ltk(conn->hcon->hdev, 1, conn->src, rp->ediv,
- rp->rand, conn->tk);
+ hci_add_ltk(conn->hcon->hdev, 1, conn->src, conn->smp_key_size,
+ rp->ediv, rp->rand, conn->tk);
smp_distribute_keys(conn, 1);
@@ -654,8 +658,8 @@
smp_send_cmd(conn, SMP_CMD_ENCRYPT_INFO, sizeof(enc), &enc);
- hci_add_ltk(conn->hcon->hdev, 1, conn->dst, ediv,
- ident.rand, enc.ltk);
+ hci_add_ltk(conn->hcon->hdev, 1, conn->dst, conn->smp_key_size,
+ ediv, ident.rand, enc.ltk);
ident.ediv = cpu_to_le16(ediv);