linux/net/bluetooth/a2mp.c

309 lines
6.3 KiB
C
Raw Normal View History

/*
Copyright (c) 2010,2011 Code Aurora Forum. All rights reserved.
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_core.h>
#include <net/bluetooth/l2cap.h>
#include <net/bluetooth/a2mp.h>
/* A2MP build & send command helper functions */
static struct a2mp_cmd *__a2mp_build(u8 code, u8 ident, u16 len, void *data)
{
struct a2mp_cmd *cmd;
int plen;
plen = sizeof(*cmd) + len;
cmd = kzalloc(plen, GFP_KERNEL);
if (!cmd)
return NULL;
cmd->code = code;
cmd->ident = ident;
cmd->len = cpu_to_le16(len);
memcpy(cmd->data, data, len);
return cmd;
}
static void a2mp_send(struct amp_mgr *mgr, u8 code, u8 ident, u16 len,
void *data)
{
struct l2cap_chan *chan = mgr->a2mp_chan;
struct a2mp_cmd *cmd;
u16 total_len = len + sizeof(*cmd);
struct kvec iv;
struct msghdr msg;
cmd = __a2mp_build(code, ident, len, data);
if (!cmd)
return;
iv.iov_base = cmd;
iv.iov_len = total_len;
memset(&msg, 0, sizeof(msg));
msg.msg_iov = (struct iovec *) &iv;
msg.msg_iovlen = 1;
l2cap_chan_send(chan, &msg, total_len, 0);
kfree(cmd);
}
/* Processing A2MP messages */
static int a2mp_command_rej(struct amp_mgr *mgr, struct sk_buff *skb,
struct a2mp_cmd *hdr)
{
struct a2mp_cmd_rej *rej = (void *) skb->data;
if (le16_to_cpu(hdr->len) < sizeof(*rej))
return -EINVAL;
BT_DBG("ident %d reason %d", hdr->ident, le16_to_cpu(rej->reason));
skb_pull(skb, sizeof(*rej));
return 0;
}
/* Handle A2MP signalling */
static int a2mp_chan_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb)
{
struct a2mp_cmd *hdr = (void *) skb->data;
struct amp_mgr *mgr = chan->data;
int err = 0;
amp_mgr_get(mgr);
while (skb->len >= sizeof(*hdr)) {
struct a2mp_cmd *hdr = (void *) skb->data;
u16 len = le16_to_cpu(hdr->len);
BT_DBG("code 0x%02x id %d len %d", hdr->code, hdr->ident, len);
skb_pull(skb, sizeof(*hdr));
if (len > skb->len || !hdr->ident) {
err = -EINVAL;
break;
}
mgr->ident = hdr->ident;
switch (hdr->code) {
case A2MP_COMMAND_REJ:
a2mp_command_rej(mgr, skb, hdr);
break;
case A2MP_DISCOVER_REQ:
case A2MP_CHANGE_NOTIFY:
case A2MP_GETINFO_REQ:
case A2MP_GETAMPASSOC_REQ:
case A2MP_CREATEPHYSLINK_REQ:
case A2MP_DISCONNPHYSLINK_REQ:
case A2MP_CHANGE_RSP:
case A2MP_DISCOVER_RSP:
case A2MP_GETINFO_RSP:
case A2MP_GETAMPASSOC_RSP:
case A2MP_CREATEPHYSLINK_RSP:
case A2MP_DISCONNPHYSLINK_RSP:
default:
BT_ERR("Unknown A2MP sig cmd 0x%2.2x", hdr->code);
err = -EINVAL;
break;
}
}
if (err) {
struct a2mp_cmd_rej rej;
rej.reason = __constant_cpu_to_le16(0);
BT_DBG("Send A2MP Rej: cmd 0x%2.2x err %d", hdr->code, err);
a2mp_send(mgr, A2MP_COMMAND_REJ, hdr->ident, sizeof(rej),
&rej);
}
/* Always free skb and return success error code to prevent
from sending L2CAP Disconnect over A2MP channel */
kfree_skb(skb);
amp_mgr_put(mgr);
return 0;
}
static void a2mp_chan_close_cb(struct l2cap_chan *chan)
{
l2cap_chan_destroy(chan);
}
static void a2mp_chan_state_change_cb(struct l2cap_chan *chan, int state)
{
struct amp_mgr *mgr = chan->data;
if (!mgr)
return;
BT_DBG("chan %p state %s", chan, state_to_string(state));
chan->state = state;
switch (state) {
case BT_CLOSED:
if (mgr)
amp_mgr_put(mgr);
break;
}
}
static struct sk_buff *a2mp_chan_alloc_skb_cb(struct l2cap_chan *chan,
unsigned long len, int nb)
{
return bt_skb_alloc(len, GFP_KERNEL);
}
static struct l2cap_chan *a2mp_chan_no_new_conn_cb(struct l2cap_chan *chan)
{
BT_ERR("new_connection for chan %p not implemented", chan);
return NULL;
}
static void a2mp_chan_no_teardown_cb(struct l2cap_chan *chan, int err)
{
BT_ERR("teardown for chan %p not implemented", chan);
}
static void a2mp_chan_no_ready(struct l2cap_chan *chan)
{
BT_ERR("ready for chan %p not implemented", chan);
}
static struct l2cap_ops a2mp_chan_ops = {
.name = "L2CAP A2MP channel",
.recv = a2mp_chan_recv_cb,
.close = a2mp_chan_close_cb,
.state_change = a2mp_chan_state_change_cb,
.alloc_skb = a2mp_chan_alloc_skb_cb,
/* Not implemented for A2MP */
.new_connection = a2mp_chan_no_new_conn_cb,
.teardown = a2mp_chan_no_teardown_cb,
.ready = a2mp_chan_no_ready,
};
static struct l2cap_chan *a2mp_chan_open(struct l2cap_conn *conn)
{
struct l2cap_chan *chan;
int err;
chan = l2cap_chan_create();
if (!chan)
return NULL;
BT_DBG("chan %p", chan);
hci_conn_hold(conn->hcon);
chan->omtu = L2CAP_A2MP_DEFAULT_MTU;
chan->imtu = L2CAP_A2MP_DEFAULT_MTU;
chan->flush_to = L2CAP_DEFAULT_FLUSH_TO;
chan->ops = &a2mp_chan_ops;
l2cap_chan_set_defaults(chan);
chan->remote_max_tx = chan->max_tx;
chan->remote_tx_win = chan->tx_win;
chan->retrans_timeout = L2CAP_DEFAULT_RETRANS_TO;
chan->monitor_timeout = L2CAP_DEFAULT_MONITOR_TO;
skb_queue_head_init(&chan->tx_q);
chan->mode = L2CAP_MODE_ERTM;
err = l2cap_ertm_init(chan);
if (err < 0) {
l2cap_chan_del(chan, 0);
return NULL;
}
chan->conf_state = 0;
l2cap_chan_add(conn, chan);
chan->remote_mps = chan->omtu;
chan->mps = chan->omtu;
chan->state = BT_CONNECTED;
return chan;
}
/* AMP Manager functions */
void amp_mgr_get(struct amp_mgr *mgr)
{
BT_DBG("mgr %p", mgr);
kref_get(&mgr->kref);
}
static void amp_mgr_destroy(struct kref *kref)
{
struct amp_mgr *mgr = container_of(kref, struct amp_mgr, kref);
BT_DBG("mgr %p", mgr);
kfree(mgr);
}
int amp_mgr_put(struct amp_mgr *mgr)
{
BT_DBG("mgr %p", mgr);
return kref_put(&mgr->kref, &amp_mgr_destroy);
}
static struct amp_mgr *amp_mgr_create(struct l2cap_conn *conn)
{
struct amp_mgr *mgr;
struct l2cap_chan *chan;
mgr = kzalloc(sizeof(*mgr), GFP_KERNEL);
if (!mgr)
return NULL;
BT_DBG("conn %p mgr %p", conn, mgr);
mgr->l2cap_conn = conn;
chan = a2mp_chan_open(conn);
if (!chan) {
kfree(mgr);
return NULL;
}
mgr->a2mp_chan = chan;
chan->data = mgr;
conn->hcon->amp_mgr = mgr;
kref_init(&mgr->kref);
return mgr;
}