linux/net/bluetooth/amp.c
Johan Hedberg 252670c421 Bluetooth: Fix sparse warning in amp.c
This fixes the following sparse warning:

net/bluetooth/amp.c:152:53: warning: Variable length array is used.

The warning itself is probably harmless since this kind of usage of
shash_desc is present also in other places in the kernel (there's even a
convenience macro SHASH_DESC_ON_STACK available for defining such stack
variables). However, dynamically allocated versions are also used in
several places of the kernel (e.g. kernel/kexec.c and lib/digsig.c)
which have the benefit of not exhibiting the sparse warning.

Since there are no more sparse warnings in the Bluetooth subsystem after
fixing this one it is now easier to spot whenever new ones might get
introduced by future patches.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-11-11 00:07:29 +01:00

475 lines
11 KiB
C

/*
Copyright (c) 2011,2012 Intel Corp.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License version 2 and
only version 2 as published by the Free Software Foundation.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
*/
#include <net/bluetooth/bluetooth.h>
#include <net/bluetooth/hci.h>
#include <net/bluetooth/hci_core.h>
#include <crypto/hash.h>
#include "a2mp.h"
#include "amp.h"
/* Remote AMP Controllers interface */
void amp_ctrl_get(struct amp_ctrl *ctrl)
{
BT_DBG("ctrl %p orig refcnt %d", ctrl,
atomic_read(&ctrl->kref.refcount));
kref_get(&ctrl->kref);
}
static void amp_ctrl_destroy(struct kref *kref)
{
struct amp_ctrl *ctrl = container_of(kref, struct amp_ctrl, kref);
BT_DBG("ctrl %p", ctrl);
kfree(ctrl->assoc);
kfree(ctrl);
}
int amp_ctrl_put(struct amp_ctrl *ctrl)
{
BT_DBG("ctrl %p orig refcnt %d", ctrl,
atomic_read(&ctrl->kref.refcount));
return kref_put(&ctrl->kref, &amp_ctrl_destroy);
}
struct amp_ctrl *amp_ctrl_add(struct amp_mgr *mgr, u8 id)
{
struct amp_ctrl *ctrl;
ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL);
if (!ctrl)
return NULL;
kref_init(&ctrl->kref);
ctrl->id = id;
mutex_lock(&mgr->amp_ctrls_lock);
list_add(&ctrl->list, &mgr->amp_ctrls);
mutex_unlock(&mgr->amp_ctrls_lock);
BT_DBG("mgr %p ctrl %p", mgr, ctrl);
return ctrl;
}
void amp_ctrl_list_flush(struct amp_mgr *mgr)
{
struct amp_ctrl *ctrl, *n;
BT_DBG("mgr %p", mgr);
mutex_lock(&mgr->amp_ctrls_lock);
list_for_each_entry_safe(ctrl, n, &mgr->amp_ctrls, list) {
list_del(&ctrl->list);
amp_ctrl_put(ctrl);
}
mutex_unlock(&mgr->amp_ctrls_lock);
}
struct amp_ctrl *amp_ctrl_lookup(struct amp_mgr *mgr, u8 id)
{
struct amp_ctrl *ctrl;
BT_DBG("mgr %p id %d", mgr, id);
mutex_lock(&mgr->amp_ctrls_lock);
list_for_each_entry(ctrl, &mgr->amp_ctrls, list) {
if (ctrl->id == id) {
amp_ctrl_get(ctrl);
mutex_unlock(&mgr->amp_ctrls_lock);
return ctrl;
}
}
mutex_unlock(&mgr->amp_ctrls_lock);
return NULL;
}
/* Physical Link interface */
static u8 __next_handle(struct amp_mgr *mgr)
{
if (++mgr->handle == 0)
mgr->handle = 1;
return mgr->handle;
}
struct hci_conn *phylink_add(struct hci_dev *hdev, struct amp_mgr *mgr,
u8 remote_id, bool out)
{
bdaddr_t *dst = &mgr->l2cap_conn->hcon->dst;
struct hci_conn *hcon;
u8 role = out ? HCI_ROLE_MASTER : HCI_ROLE_SLAVE;
hcon = hci_conn_add(hdev, AMP_LINK, dst, role);
if (!hcon)
return NULL;
BT_DBG("hcon %p dst %pMR", hcon, dst);
hcon->state = BT_CONNECT;
hcon->attempt++;
hcon->handle = __next_handle(mgr);
hcon->remote_id = remote_id;
hcon->amp_mgr = amp_mgr_get(mgr);
return hcon;
}
/* AMP crypto key generation interface */
static int hmac_sha256(u8 *key, u8 ksize, char *plaintext, u8 psize, u8 *output)
{
struct crypto_shash *tfm;
struct shash_desc *shash;
int ret;
if (!ksize)
return -EINVAL;
tfm = crypto_alloc_shash("hmac(sha256)", 0, 0);
if (IS_ERR(tfm)) {
BT_DBG("crypto_alloc_ahash failed: err %ld", PTR_ERR(tfm));
return PTR_ERR(tfm);
}
ret = crypto_shash_setkey(tfm, key, ksize);
if (ret) {
BT_DBG("crypto_ahash_setkey failed: err %d", ret);
goto failed;
}
shash = kzalloc(sizeof(*shash) + crypto_shash_descsize(tfm),
GFP_KERNEL);
if (!shash) {
ret = -ENOMEM;
goto failed;
}
shash->tfm = tfm;
shash->flags = CRYPTO_TFM_REQ_MAY_SLEEP;
ret = crypto_shash_digest(shash, plaintext, psize, output);
kfree(shash);
failed:
crypto_free_shash(tfm);
return ret;
}
int phylink_gen_key(struct hci_conn *conn, u8 *data, u8 *len, u8 *type)
{
struct hci_dev *hdev = conn->hdev;
struct link_key *key;
u8 keybuf[HCI_AMP_LINK_KEY_SIZE];
u8 gamp_key[HCI_AMP_LINK_KEY_SIZE];
int err;
if (!hci_conn_check_link_mode(conn))
return -EACCES;
BT_DBG("conn %p key_type %d", conn, conn->key_type);
/* Legacy key */
if (conn->key_type < 3) {
BT_ERR("Legacy key type %d", conn->key_type);
return -EACCES;
}
*type = conn->key_type;
*len = HCI_AMP_LINK_KEY_SIZE;
key = hci_find_link_key(hdev, &conn->dst);
if (!key) {
BT_DBG("No Link key for conn %p dst %pMR", conn, &conn->dst);
return -EACCES;
}
/* BR/EDR Link Key concatenated together with itself */
memcpy(&keybuf[0], key->val, HCI_LINK_KEY_SIZE);
memcpy(&keybuf[HCI_LINK_KEY_SIZE], key->val, HCI_LINK_KEY_SIZE);
/* Derive Generic AMP Link Key (gamp) */
err = hmac_sha256(keybuf, HCI_AMP_LINK_KEY_SIZE, "gamp", 4, gamp_key);
if (err) {
BT_ERR("Could not derive Generic AMP Key: err %d", err);
return err;
}
if (conn->key_type == HCI_LK_DEBUG_COMBINATION) {
BT_DBG("Use Generic AMP Key (gamp)");
memcpy(data, gamp_key, HCI_AMP_LINK_KEY_SIZE);
return err;
}
/* Derive Dedicated AMP Link Key: "802b" is 802.11 PAL keyID */
return hmac_sha256(gamp_key, HCI_AMP_LINK_KEY_SIZE, "802b", 4, data);
}
void amp_read_loc_assoc_frag(struct hci_dev *hdev, u8 phy_handle)
{
struct hci_cp_read_local_amp_assoc cp;
struct amp_assoc *loc_assoc = &hdev->loc_assoc;
BT_DBG("%s handle %d", hdev->name, phy_handle);
cp.phy_handle = phy_handle;
cp.max_len = cpu_to_le16(hdev->amp_assoc_size);
cp.len_so_far = cpu_to_le16(loc_assoc->offset);
hci_send_cmd(hdev, HCI_OP_READ_LOCAL_AMP_ASSOC, sizeof(cp), &cp);
}
void amp_read_loc_assoc(struct hci_dev *hdev, struct amp_mgr *mgr)
{
struct hci_cp_read_local_amp_assoc cp;
memset(&hdev->loc_assoc, 0, sizeof(struct amp_assoc));
memset(&cp, 0, sizeof(cp));
cp.max_len = cpu_to_le16(hdev->amp_assoc_size);
set_bit(READ_LOC_AMP_ASSOC, &mgr->state);
hci_send_cmd(hdev, HCI_OP_READ_LOCAL_AMP_ASSOC, sizeof(cp), &cp);
}
void amp_read_loc_assoc_final_data(struct hci_dev *hdev,
struct hci_conn *hcon)
{
struct hci_cp_read_local_amp_assoc cp;
struct amp_mgr *mgr = hcon->amp_mgr;
cp.phy_handle = hcon->handle;
cp.len_so_far = cpu_to_le16(0);
cp.max_len = cpu_to_le16(hdev->amp_assoc_size);
set_bit(READ_LOC_AMP_ASSOC_FINAL, &mgr->state);
/* Read Local AMP Assoc final link information data */
hci_send_cmd(hdev, HCI_OP_READ_LOCAL_AMP_ASSOC, sizeof(cp), &cp);
}
/* Write AMP Assoc data fragments, returns true with last fragment written*/
static bool amp_write_rem_assoc_frag(struct hci_dev *hdev,
struct hci_conn *hcon)
{
struct hci_cp_write_remote_amp_assoc *cp;
struct amp_mgr *mgr = hcon->amp_mgr;
struct amp_ctrl *ctrl;
u16 frag_len, len;
ctrl = amp_ctrl_lookup(mgr, hcon->remote_id);
if (!ctrl)
return false;
if (!ctrl->assoc_rem_len) {
BT_DBG("all fragments are written");
ctrl->assoc_rem_len = ctrl->assoc_len;
ctrl->assoc_len_so_far = 0;
amp_ctrl_put(ctrl);
return true;
}
frag_len = min_t(u16, 248, ctrl->assoc_rem_len);
len = frag_len + sizeof(*cp);
cp = kzalloc(len, GFP_KERNEL);
if (!cp) {
amp_ctrl_put(ctrl);
return false;
}
BT_DBG("hcon %p ctrl %p frag_len %u assoc_len %u rem_len %u",
hcon, ctrl, frag_len, ctrl->assoc_len, ctrl->assoc_rem_len);
cp->phy_handle = hcon->handle;
cp->len_so_far = cpu_to_le16(ctrl->assoc_len_so_far);
cp->rem_len = cpu_to_le16(ctrl->assoc_rem_len);
memcpy(cp->frag, ctrl->assoc, frag_len);
ctrl->assoc_len_so_far += frag_len;
ctrl->assoc_rem_len -= frag_len;
amp_ctrl_put(ctrl);
hci_send_cmd(hdev, HCI_OP_WRITE_REMOTE_AMP_ASSOC, len, cp);
kfree(cp);
return false;
}
void amp_write_rem_assoc_continue(struct hci_dev *hdev, u8 handle)
{
struct hci_conn *hcon;
BT_DBG("%s phy handle 0x%2.2x", hdev->name, handle);
hcon = hci_conn_hash_lookup_handle(hdev, handle);
if (!hcon)
return;
/* Send A2MP create phylink rsp when all fragments are written */
if (amp_write_rem_assoc_frag(hdev, hcon))
a2mp_send_create_phy_link_rsp(hdev, 0);
}
void amp_write_remote_assoc(struct hci_dev *hdev, u8 handle)
{
struct hci_conn *hcon;
BT_DBG("%s phy handle 0x%2.2x", hdev->name, handle);
hcon = hci_conn_hash_lookup_handle(hdev, handle);
if (!hcon)
return;
BT_DBG("%s phy handle 0x%2.2x hcon %p", hdev->name, handle, hcon);
amp_write_rem_assoc_frag(hdev, hcon);
}
void amp_create_phylink(struct hci_dev *hdev, struct amp_mgr *mgr,
struct hci_conn *hcon)
{
struct hci_cp_create_phy_link cp;
cp.phy_handle = hcon->handle;
BT_DBG("%s hcon %p phy handle 0x%2.2x", hdev->name, hcon,
hcon->handle);
if (phylink_gen_key(mgr->l2cap_conn->hcon, cp.key, &cp.key_len,
&cp.key_type)) {
BT_DBG("Cannot create link key");
return;
}
hci_send_cmd(hdev, HCI_OP_CREATE_PHY_LINK, sizeof(cp), &cp);
}
void amp_accept_phylink(struct hci_dev *hdev, struct amp_mgr *mgr,
struct hci_conn *hcon)
{
struct hci_cp_accept_phy_link cp;
cp.phy_handle = hcon->handle;
BT_DBG("%s hcon %p phy handle 0x%2.2x", hdev->name, hcon,
hcon->handle);
if (phylink_gen_key(mgr->l2cap_conn->hcon, cp.key, &cp.key_len,
&cp.key_type)) {
BT_DBG("Cannot create link key");
return;
}
hci_send_cmd(hdev, HCI_OP_ACCEPT_PHY_LINK, sizeof(cp), &cp);
}
void amp_physical_cfm(struct hci_conn *bredr_hcon, struct hci_conn *hs_hcon)
{
struct hci_dev *bredr_hdev = hci_dev_hold(bredr_hcon->hdev);
struct amp_mgr *mgr = hs_hcon->amp_mgr;
struct l2cap_chan *bredr_chan;
BT_DBG("bredr_hcon %p hs_hcon %p mgr %p", bredr_hcon, hs_hcon, mgr);
if (!bredr_hdev || !mgr || !mgr->bredr_chan)
return;
bredr_chan = mgr->bredr_chan;
l2cap_chan_lock(bredr_chan);
set_bit(FLAG_EFS_ENABLE, &bredr_chan->flags);
bredr_chan->remote_amp_id = hs_hcon->remote_id;
bredr_chan->local_amp_id = hs_hcon->hdev->id;
bredr_chan->hs_hcon = hs_hcon;
bredr_chan->conn->mtu = hs_hcon->hdev->block_mtu;
__l2cap_physical_cfm(bredr_chan, 0);
l2cap_chan_unlock(bredr_chan);
hci_dev_put(bredr_hdev);
}
void amp_create_logical_link(struct l2cap_chan *chan)
{
struct hci_conn *hs_hcon = chan->hs_hcon;
struct hci_cp_create_accept_logical_link cp;
struct hci_dev *hdev;
BT_DBG("chan %p hs_hcon %p dst %pMR", chan, hs_hcon,
&chan->conn->hcon->dst);
if (!hs_hcon)
return;
hdev = hci_dev_hold(chan->hs_hcon->hdev);
if (!hdev)
return;
cp.phy_handle = hs_hcon->handle;
cp.tx_flow_spec.id = chan->local_id;
cp.tx_flow_spec.stype = chan->local_stype;
cp.tx_flow_spec.msdu = cpu_to_le16(chan->local_msdu);
cp.tx_flow_spec.sdu_itime = cpu_to_le32(chan->local_sdu_itime);
cp.tx_flow_spec.acc_lat = cpu_to_le32(chan->local_acc_lat);
cp.tx_flow_spec.flush_to = cpu_to_le32(chan->local_flush_to);
cp.rx_flow_spec.id = chan->remote_id;
cp.rx_flow_spec.stype = chan->remote_stype;
cp.rx_flow_spec.msdu = cpu_to_le16(chan->remote_msdu);
cp.rx_flow_spec.sdu_itime = cpu_to_le32(chan->remote_sdu_itime);
cp.rx_flow_spec.acc_lat = cpu_to_le32(chan->remote_acc_lat);
cp.rx_flow_spec.flush_to = cpu_to_le32(chan->remote_flush_to);
if (hs_hcon->out)
hci_send_cmd(hdev, HCI_OP_CREATE_LOGICAL_LINK, sizeof(cp),
&cp);
else
hci_send_cmd(hdev, HCI_OP_ACCEPT_LOGICAL_LINK, sizeof(cp),
&cp);
hci_dev_put(hdev);
}
void amp_disconnect_logical_link(struct hci_chan *hchan)
{
struct hci_conn *hcon = hchan->conn;
struct hci_cp_disconn_logical_link cp;
if (hcon->state != BT_CONNECTED) {
BT_DBG("hchan %p not connected", hchan);
return;
}
cp.log_handle = cpu_to_le16(hchan->handle);
hci_send_cmd(hcon->hdev, HCI_OP_DISCONN_LOGICAL_LINK, sizeof(cp), &cp);
}
void amp_destroy_logical_link(struct hci_chan *hchan, u8 reason)
{
BT_DBG("hchan %p", hchan);
hci_chan_del(hchan);
}