/*
* QEMU Bluetooth L2CAP logic.
*
* Copyright (C) 2008 Andrzej Zaborowski <balrog@zabor.org>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see <http://www.gnu.org/licenses/>.
*/
#include "qemu-common.h"
#include "qemu/timer.h"
#include "hw/bt.h"
#define L2CAP_CID_MAX 0x100 /* Between 0x40 and 0x10000 */
struct l2cap_instance_s {
struct bt_link_s *link;
struct bt_l2cap_device_s *dev;
int role;
uint8_t frame_in[65535 + L2CAP_HDR_SIZE] __attribute__ ((aligned (4)));
int frame_in_len;
uint8_t frame_out[65535 + L2CAP_HDR_SIZE] __attribute__ ((aligned (4)));
int frame_out_len;
/* Signalling channel timers. They exist per-request but we can make
* sure we have no more than one outstanding request at any time. */
QEMUTimer *rtx;
QEMUTimer *ertx;
int last_id;
int next_id;
struct l2cap_chan_s {
struct bt_l2cap_conn_params_s params;
void (*frame_in)(struct l2cap_chan_s *chan, uint16_t cid,
const l2cap_hdr *hdr, int len);
int mps;
int min_mtu;
struct l2cap_instance_s *l2cap;
/* Only allocated channels */
uint16_t remote_cid;
#define L2CAP_CFG_INIT 2
#define L2CAP_CFG_ACC 1
int config_req_id; /* TODO: handle outgoing requests generically */
int config;
/* Only connection-oriented channels. Note: if we allow the tx and
* rx traffic to be in different modes at any time, we need two. */
int mode;
/* Only flow-controlled, connection-oriented channels */
uint8_t sdu[65536]; /* TODO: dynamically allocate */
int len_cur, len_total;
int rexmit;
int monitor_timeout;
QEMUTimer *monitor_timer;
QEMUTimer *retransmission_timer;
} *cid[L2CAP_CID_MAX];
/* The channel state machine states map as following:
* CLOSED -> !cid[N]
* WAIT_CONNECT -> never occurs
* WAIT_CONNECT_RSP -> never occurs
* CONFIG -> cid[N] && config < 3
* WAIT_CONFIG -> never occurs, cid[N] && config == 0 && !config_r
* WAIT_SEND_CONFIG -> never occurs, cid[N] && config == 1 && !config_r
* WAIT_CONFIG_REQ_RSP -> cid[N] && config == 0 && config_req_id
* WAIT_CONFIG_RSP -> cid[N] && config == 1 && config_req_id
* WAIT_CONFIG_REQ -> cid[N] && config == 2
* OPEN -> cid[N] && config == 3
* WAIT_DISCONNECT -> never occurs
*/
struct l2cap_chan_s signalling_ch;
struct l2cap_chan_s group_ch;
};
struct slave_l2cap_instance_s {
struct bt_link_s link; /* Underlying logical link (ACL) */
struct l2cap_instance_s l2cap;
};
struct bt_l2cap_psm_s {
int psm;
int min_mtu;
int (*new_channel)(struct bt_l2cap_device_s *device,
struct bt_l2cap_conn_params_s *params);
struct bt_l2cap_psm_s *next;
};
static const uint16_t l2cap_fcs16_table[256] = {
0x0000, 0xc0c1, 0xc181, 0x0140, 0xc301, 0x03c0, 0x0280, 0xc241,
0xc601, 0x06c0, 0x0780, 0xc741, 0x0500, 0xc5c1, 0xc481, 0x0440,
0xcc01, 0x0cc0, 0x0d80, 0xcd41, 0x0f00, 0xcfc1, 0xce81, 0x0e40,
0x0a00, 0xcac1, 0xcb81, 0x0b40, 0xc901, 0x09c0, 0x0880, 0xc841,
0xd801, 0x18c0, 0x1980, 0xd941, 0x1b00, 0xdbc1, 0xda81, 0x1a40,
0x1e00, 0xdec1, 0xdf81, 0x1f40, 0xdd01, 0x1dc0, 0x1c80, 0xdc41,
0x1400, 0xd4c1, 0xd581, 0x1540, 0xd701, 0x17c0, 0x1680, 0xd641,
0xd201, 0x12c0, 0x1380, 0xd341, 0x1100, 0xd1c1, 0xd081, 0x1040,
0xf001, 0x30c0, 0x3180, 0xf141, 0x3300, 0xf3c1, 0xf281, 0x3240,
0x3600, 0xf6c1, 0xf781, 0x3740, 0xf501, 0x35c0, 0x3480, 0xf441,
0x3c00, 0xfcc1, 0xfd81, 0x3d40, 0xff01, 0x3fc0, 0x3e80, 0xfe41,
0xfa01, 0x3ac0, 0x3b80, 0xfb41, 0x3900, 0xf9c1, 0xf881, 0x3840,
0x2800, 0xe8c1, 0xe981, 0x2940, 0xeb01, 0x2bc0, 0x2a80, 0xea41,
0xee01, 0x2ec0, 0x2f80, 0xef41, 0x2d00, 0xedc1, 0xec81, 0x2c40,
0xe401, 0x24c0, 0x2580, 0xe541, 0x2700, 0xe7c1, 0xe681, 0x2640,
0x2200, 0xe2c1, 0xe381, 0x2340, 0xe101, 0x21c0, 0x2080, 0xe041,
0xa001, 0x60c0, 0x6180, 0xa141, 0x6300, 0xa3c1, 0xa281, 0x6240,
0x6600, 0xa6c1, 0xa781, 0x6740, 0xa501, 0x65c0, 0x6480, 0xa441,
0x6c00, 0xacc1, 0xad81, 0x6d40, 0xaf01, 0x6fc0, 0x6e80, 0xae41,
0xaa01, 0x6ac0, 0x6b80, 0xab41, 0x6900, 0xa9c1, 0xa881, 0x6840,
0x7800, 0xb8c1, 0xb981, 0x7940, 0xbb01, 0x7bc0, 0x7a80, 0xba41,
0xbe01, 0x7ec0, 0x7f80, 0xbf41, 0x7d00, 0xbdc1, 0xbc81, 0x7c40,
0xb401, 0x74c0, 0x7580, 0xb541, 0x7700, 0xb7c1, 0xb681, 0x7640,
0x7200, 0xb2c1, 0xb381, 0x7340, 0xb101, 0x71c0, 0x7080, 0xb041,
0x5000, 0x90c1, 0x9181, 0x5140, 0x9301, 0x53c0, 0x5280, 0x9241,
0x9601, 0x56c0, 0x5780, 0x9741, 0x5500, 0x95c1, 0x9481, 0x5440,
0x9c01, 0x5cc0, 0x5d80, 0x9d41, 0x5f00, 0x9fc1, 0x9e81, 0x5e40,
0x5a00, 0x9ac1, 0x9b81, 0x5b40, 0x9901, 0x59c0, 0x5880, 0x9841,
0x8801, 0x48c0, 0x4980, 0x8941, 0x4b00, 0x8bc1, 0x8a81, 0x4a40,
0x4e00, 0x8ec1, 0x8f81, 0x4f40, 0x8d01, 0x4dc0, 0x4c80, 0x8c41,
0x4400, 0x84c1, 0x8581, 0x4540, 0x8701, 0x47c0, 0x4680, 0x8641,
0x8201, 0x42c0, 0x4380, 0x8341, 0x4100, 0x81c1, 0x8081, 0x4040,
};
static uint16_t l2cap_fcs16(const uint8_t *message, int len)
{
uint16_t fcs = 0x0000;
while (len --)
#if 0
{
int i;
fcs ^= *message ++;
for (i = 8; i; -- i)
if (fcs & 1)
fcs = (fcs >> 1) ^ 0xa001;
else
fcs = (fcs >> 1);
}
#else
fcs = (fcs >> 8) ^ l2cap_fcs16_table[(fcs ^ *message ++) & 0xff];
#endif
return fcs;
}
/* L2CAP layer logic (protocol) */
static void l2cap_retransmission_timer_update(struct l2cap_chan_s *ch)
{
#if 0
if (ch->mode != L2CAP_MODE_BASIC && ch->rexmit)
timer_mod(ch->retransmission_timer);
else
timer_del(ch->retransmission_timer);
#endif
}
static void l2cap_monitor_timer_update(struct l2cap_chan_s *ch)
{
#if 0
if (ch->mode != L2CAP_MODE_BASIC && !ch->rexmit)
timer_mod(ch->monitor_timer);
else
timer_del(ch->monitor_timer);
#endif
}
static void l2cap_command_reject(struct l2cap_instance_s *l2cap, int id,
uint16_t reason, const void *data, int plen)
{
uint8_t *pkt;
l2cap_cmd_hdr *hdr;
l2cap_cmd_rej *params;
uint16_t len;
reason = cpu_to_le16(reason);
len = cpu_to_le16(L2CAP_CMD_REJ_SIZE + plen);
pkt = l2cap->signalling_ch.params.sdu_out(&l2cap->signalling_ch.params,
L2CAP_CMD_HDR_SIZE + L2CAP_CMD_REJ_SIZE + plen);
hdr = (void *) (pkt + 0);
params = (void *) (pkt + L2CAP_CMD_HDR_SIZE);
hdr->code = L2CAP_COMMAND_REJ;
hdr->ident = id;
memcpy(&hdr->len, &len, sizeof(hdr->len));
memcpy(¶ms->reason, &reason, sizeof(reason));
if (plen)
memcpy(pkt + L2CAP_CMD_HDR_SIZE + L2CAP_CMD_REJ_SIZE, data, plen);
l2cap->signalling_ch.params.sdu_submit(&l2cap->signalling_ch.params);
}
static void l2cap_command_reject_cid(struct l2cap_instance_s *l2cap, int id,
uint16_t reason, uint16_t dcid, uint16_t scid)
{
l2cap_cmd_rej_cid params = {
.dcid = dcid,
.scid = scid,
};
l2cap_command_reject(l2cap, id, reason, ¶ms, L2CAP_CMD_REJ_CID_SIZE);
}
static void l2cap_connection_response(struct l2cap_instance_s *l2cap,
int dcid, int scid, int result, int status)
{
uint8_t *pkt;
l2cap_cmd_hdr *hdr;
l2cap_conn_rsp *params;
pkt = l2cap->signalling_ch.params.sdu_out(&l2cap->signalling_ch.params,
L2CAP_CMD_HDR_SIZE + L2CAP_CONN_RSP_SIZE);
hdr = (void *) (pkt + 0);
params = (void *) (pkt + L2CAP_CMD_HDR_SIZE);
hdr->code = L2CAP_CONN_RSP;
hdr->ident = l2cap->last_id;
hdr->len = cpu_to_le16(L2CAP_CONN_RSP_SIZE);
params->dcid = cpu_to_le16(dcid);
params->scid = cpu_to_le16(scid);
params->result = cpu_to_le16(result);
params->status = cpu_to_le16(status);
l2cap->signalling_ch.params.sdu_submit(&l2cap->signalling_ch.params);
}
static void l2cap_configuration_request(struct l2cap_instance_s *l2cap,
int dcid, int flag, const uint8_t *data, int len)
{
uint8_t *pkt;
l2cap_cmd_hdr *hdr;
l2cap_conf_req *params;
pkt = l2cap->signalling_ch.params.sdu_out(&l2cap->signalling_ch.params,
L2CAP_CMD_HDR_SIZE + L2CAP_CONF_REQ_SIZE(len));
hdr = (void *) (pkt + 0);
params = (void *) (pkt + L2CAP_CMD_HDR_SIZE);
/* TODO: unify the id sequencing */
l2cap->last_id = l2cap->next_id;
l2cap->next_id = l2cap->next_id == 255 ? 1 : l2cap->next_id + 1;
hdr->code = L2CAP_CONF_REQ;
hdr->ident = l2cap->last_id;
hdr->len = cpu_to_le16(L2CAP_CONF_REQ_SIZE(len));
params->dcid = cpu_to_le16(dcid);
params->flags = cpu_to_le16(flag);
if (len)
memcpy(params->data, data, len);
l2cap->signalling_ch.params.sdu_submit(&l2cap->signalling_ch.params);
}
static void l2cap_configuration_response(struct l2cap_instance_s *l2cap,
int scid, int flag, int result, const uint8_t *data, int len)
{
uint8_t *pkt;
l2cap_cmd_hdr *hdr;
l2cap_conf_rsp *params;
pkt = l2cap->signalling_ch.params.sdu_out(&l2cap->signalling_ch.params,
L2CAP_CMD_HDR_SIZE + L2CAP_CONF_RSP_SIZE(len));
hdr = (void *) (pkt + 0);
params = (void *) (pkt + L2CAP_CMD_HDR_SIZE);
hdr->code = L2CAP_CONF_RSP;
hdr->ident = l2cap->last_id;
hdr->len = cpu_to_le16(L2CAP_CONF_RSP_SIZE(len));
params->scid = cpu_to_le16(scid);
params->flags = cpu_to_le16(flag);
params->result = cpu_to_le16(result);
if (len)
memcpy(params->data, data, len);
l2cap->signalling_ch.params.sdu_submit(&l2cap->signalling_ch.params);
}
static void l2cap_disconnection_response(struct l2cap_instance_s *l2cap,
int dcid, int scid)
{
uint8_t *pkt;
l2cap_cmd_hdr *hdr;
l2cap_disconn_rsp *params;
pkt = l2cap->signalling_ch.params.sdu_out(&l2cap->signalling_ch.params,
L2CAP_CMD_HDR_SIZE + L2CAP_DISCONN_RSP_SIZE);
hdr = (void *) (pkt + 0);
params = (void *) (pkt + L2CAP_CMD_HDR_SIZE);
hdr->code = L2CAP_DISCONN_RSP;
hdr->ident = l2cap->last_id;
hdr->len = cpu_to_le16(L2CAP_DISCONN_RSP_SIZE);
params->dcid = cpu_to_le16(dcid);
params->scid = cpu_to_le16(scid);
l2cap->signalling_ch.params.sdu_submit(&l2cap->signalling_ch.params);
}
static void l2cap_echo_response(struct l2cap_instance_s *l2cap,
const uint8_t *data, int len)
{
uint8_t *pkt;
l2cap_cmd_hdr *hdr;
uint8_t *params;
pkt = l2cap->signalling_ch.params.sdu_out(&l2cap->signalling_ch.params,
L2CAP_CMD_HDR_SIZE + len);
hdr = (void *) (pkt + 0);
params = (void *) (pkt + L2CAP_CMD_HDR_SIZE);
hdr->code = L2CAP_ECHO_RSP;
hdr->ident = l2cap->last_id;
hdr->len = cpu_to_le16(len);
memcpy(params, data, len);
l2cap->signalling_ch.params.sdu_submit(&l2cap->signalling_ch.params);
}
static void l2cap_info_response(struct l2cap_instance_s *l2cap, int type,
int result, const uint8_t *data, int len)
{
uint8_t *pkt;
l2cap_cmd_hdr *hdr;
l2cap_info_rsp *params;
pkt = l2cap->signalling_ch.params.sdu_out(&l2cap->signalling_ch.params,
L2CAP_CMD_HDR_SIZE + L2CAP_INFO_RSP_SIZE + len);
hdr = (void *) (pkt + 0);
params = (void *) (pkt + L2CAP_CMD_HDR_SIZE);
hdr->code = L2CAP_INFO_RSP;
hdr->ident = l2cap->last_id;
hdr->len = cpu_to_le16(L2CAP_INFO_RSP_SIZE + len);
params->type = cpu_to_le16(type);
params->result = cpu_to_le16(result);
if (len)
memcpy(params->data, data, len);
l2cap->signalling_ch.params.sdu_submit(&l2cap->signalling_ch.params);
}
static uint8_t *l2cap_bframe_out(struct bt_l2cap_conn_params_s *parm, int len);
static void l2cap_bframe_submit(struct bt_l2cap_conn_params_s *parms);
#if 0
static uint8_t *l2cap_iframe_out(struct bt_l2cap_conn_params_s *parm, int len);
static void l2cap_iframe_submit(struct bt_l2cap_conn_params_s *parm);
#endif
static void l2cap_bframe_in(struct l2cap_chan_s *ch, uint16_t cid,
const l2cap_hdr *hdr, int len);
static void l2cap_iframe_in(struct l2cap_chan_s *ch, uint16_t cid,
const l2cap_hdr *hdr, int len);
static int l2cap_cid_new(struct l2cap_instance_s *l2cap)
{
int i;
for (i = L2CAP_CID_ALLOC; i < L2CAP_CID_MAX; i ++)
if (!l2cap->cid[i])
return i;
return L2CAP_CID_INVALID;
}
static inline struct bt_l2cap_psm_s *l2cap_psm(
struct bt_l2cap_device_s *device, int psm)
{
struct bt_l2cap_psm_s *ret = device->first_psm;
while (ret && ret->psm != psm)
ret = ret->next;
return ret;
}
static struct l2cap_chan_s *l2cap_channel_open(struct l2cap_instance_s *l2cap,
int psm, int source_cid)
{
struct l2cap_chan_s *ch = NULL;
struct bt_l2cap_psm_s *psm_info;
int result, status;
int cid = l2cap_cid_new(l2cap);
if (cid) {
/* See what the channel is to be used for.. */
psm_info = l2cap_psm(l2cap->dev, psm);
if (psm_info) {
/* Device supports this use-case. */
ch = g_malloc0(sizeof(*ch));
ch->params.sdu_out = l2cap_bframe_out;
ch->params.sdu_submit = l2cap_bframe_submit;
ch->frame_in = l2cap_bframe_in;
ch->mps = 65536;
ch->min_mtu = MAX(48, psm_info->min_mtu);
ch->params.remote_mtu = MAX(672, ch->min_mtu);
ch->remote_cid = source_cid;
ch->mode = L2CAP_MODE_BASIC;
ch->l2cap = l2cap;
/* Does it feel like opening yet another channel though? */
if (!psm_info->new_channel(l2cap->dev, &ch->params)) {
l2cap->cid[cid] = ch;
result = L2CAP_CR_SUCCESS;
status = L2CAP_CS_NO_INFO;
} else {
g_free(ch);
ch = NULL;
result = L2CAP_CR_NO_MEM;
status = L2CAP_CS_NO_INFO;
}
} else {
result = L2CAP_CR_BAD_PSM;
status = L2CAP_CS_NO_INFO;
}
} else {
result = L2CAP_CR_NO_MEM;
status = L2CAP_CS_NO_INFO;
}
l2cap_connection_response(l2cap, cid, source_cid, result, status);
return ch;
}
static void l2cap_channel_close(struct l2cap_instance_s *l2cap,
int cid, int source_cid)
{
struct l2cap_chan_s *ch = NULL;
/* According to Volume 3, section 6.1.1, pg 1048 of BT Core V2.0, a
* connection in CLOSED state still responds with a L2CAP_DisconnectRsp
* message on an L2CAP_DisconnectReq event. */
if (unlikely(cid < L2CAP_CID_ALLOC)) {
l2cap_command_reject_cid(l2cap, l2cap->last_id, L2CAP_REJ_CID_INVAL,
cid, source_cid);
return;
}
if (likely(cid >= L2CAP_CID_ALLOC && cid < L2CAP_CID_MAX))
ch = l2cap->cid[cid];
if (likely(ch)) {
if (ch->remote_cid != source_cid) {
fprintf(stderr, "%s: Ignoring a Disconnection Request with the "
"invalid SCID %04x.\n", __FUNCTION__, source_cid);
return;
}
l2cap->cid[cid] = NULL;
ch->params.close(ch->params.opaque);
g_free(ch);
}
l2cap_disconnection_response(l2cap, cid, source_cid);
}
static void l2cap_channel_config_null(struct l2cap_instance_s *l2cap,
struct l2cap_chan_s *ch)
{
l2cap_configuration_request(l2cap, ch->remote_cid, 0, NULL, 0);
ch->config_req_id = l2cap->last_id;
ch->config &= ~L2CAP_CFG_INIT;
}
static void l2cap_channel_config_req_event(struct l2cap_instance_s *l2cap,
struct l2cap_chan_s *ch)
{
/* Use all default channel options and terminate negotiation. */
l2cap_channel_config_null(l2cap, ch);
}
static int l2cap_channel_config(struct l2cap_instance_s *l2cap,
struct l2cap_chan_s *ch, int flag,
const uint8_t *data, int len)
{
l2cap_conf_opt *opt;
l2cap_conf_opt_qos *qos;
uint32_t val;
uint8_t rsp[len];
int result = L2CAP_CONF_SUCCESS;
data = memcpy(rsp, data, len);
while (len) {
opt = (void *) data;
if (len < L2CAP_CONF_OPT_SIZE ||
len < L2CAP_CONF_OPT_SIZE + opt->len) {
result = L2CAP_CONF_REJECT;
break;
}
data += L2CAP_CONF_OPT_SIZE + opt->len;
len -= L2CAP_CONF_OPT_SIZE + opt->len;
switch (opt->type & 0x7f) {
case L2CAP_CONF_MTU:
if (opt->len != 2) {
result = L2CAP_CONF_REJECT;
break;
}
/* MTU */
val = le16_to_cpup((void *) opt->val);
if (val < ch->min_mtu) {
cpu_to_le16w((void *) opt->val, ch->min_mtu);
result = L2CAP_CONF_UNACCEPT;
break;
}
ch->params.remote_mtu = val;
break;
case L2CAP_CONF_FLUSH_TO:
if (opt->len != 2) {
result = L2CAP_CONF_REJECT;
break;
}
/* Flush Timeout */
val = le16_to_cpup((void *) opt->val);
if (val < 0x0001) {
opt->val[0] = 0xff;
opt->val[1] = 0xff;
result = L2CAP_CONF_UNACCEPT;
break;
}
break;
case L2CAP_CONF_QOS:
if (opt->len != L2CAP_CONF_OPT_QOS_SIZE) {
result = L2CAP_CONF_REJECT;
break;
}
qos = (void *) opt->val;
/* Flags */
val = qos->flags;
if (val) {
qos->flags = 0;
result = L2CAP_CONF_UNACCEPT;
}
/* Service type */
val = qos->service_type;
if (val != L2CAP_CONF_QOS_BEST_EFFORT &&
val != L2CAP_CONF_QOS_NO_TRAFFIC) {
qos->service_type = L2CAP_CONF_QOS_BEST_EFFORT;
result = L2CAP_CONF_UNACCEPT;
}
if (val != L2CAP_CONF_QOS_NO_TRAFFIC) {
/* XXX: These values should possibly be calculated
* based on LM / baseband properties also. */
/* Token rate */
val = le32_to_cpu(qos->token_rate);
if (val == L2CAP_CONF_QOS_WILDCARD)
qos->token_rate = cpu_to_le32(0x100000);
/* Token bucket size */
val = le32_to_cpu(qos->token_bucket_size);
if (val == L2CAP_CONF_QOS_WILDCARD)
qos->token_bucket_size = cpu_to_le32(65500);
/* Any Peak bandwidth value is correct to return as-is */
/* Any Access latency value is correct to return as-is */
/* Any Delay variation value is correct to return as-is */
}
break;
case L2CAP_CONF_RFC:
if (opt->len != 9) {
result = L2CAP_CONF_REJECT;
break;
}
/* Mode */
val = opt->val[0];
switch (val) {
case L2CAP_MODE_BASIC:
ch->mode = val;
ch->frame_in = l2cap_bframe_in;
/* All other parameters shall be ignored */
break;
case L2CAP_MODE_RETRANS:
case L2CAP_MODE_FLOWCTL:
ch->mode = val;
ch->frame_in = l2cap_iframe_in;
/* Note: most of these parameters refer to incoming traffic
* so we don't need to save them as long as we can accept
* incoming PDUs at any values of the parameters. */
/* TxWindow size */
val = opt->val[1];
if (val < 1 || val > 32) {
opt->val[1] = 32;
result = L2CAP_CONF_UNACCEPT;
break;
}
/* MaxTransmit */
val = opt->val[2];
if (val < 1) {
opt->val[2] = 1;
result = L2CAP_CONF_UNACCEPT;
break;
}
/* Remote Retransmission time-out shouldn't affect local
* operation (?) */
/* The Monitor time-out drives the local Monitor timer (?),
* so save the value. */
val = (opt->val[6] << 8) | opt->val[5];
if (val < 30) {
opt->val[5] = 100 & 0xff;
opt->val[6] = 100 >> 8;
result = L2CAP_CONF_UNACCEPT;
break;
}
ch->monitor_timeout = val;
l2cap_monitor_timer_update(ch);
/* MPS */
val = (opt->val[8] << 8) | opt->val[7];
if (val < ch->min_mtu) {
opt->val[7] = ch->min_mtu & 0xff;
opt->val[8] = ch->min_mtu >> 8;
result = L2CAP_CONF_UNACCEPT;
break;
}
ch->mps = val;
break;
default:
result = L2CAP_CONF_UNACCEPT;
break;
}
break;
default:
if (!(opt->type >> 7))
result = L2CAP_CONF_UNKNOWN;
break;
}
if (result != L2CAP_CONF_SUCCESS)
break; /* XXX: should continue? */
}
l2cap_configuration_response(l2cap, ch->remote_cid,
flag, result, rsp, len);
return result == L2CAP_CONF_SUCCESS && !flag;
}
static void l2cap_channel_config_req_msg(struct l2cap_instance_s *l2cap,
int flag, int cid, const uint8_t *data, int len)
{
struct l2cap_chan_s *ch;
if (unlikely(cid >= L2CAP_CID_MAX || !l2cap->cid[cid])) {
l2cap_command_reject_cid(l2cap, l2cap->last_id, L2CAP_REJ_CID_INVAL,
cid, 0x0000);
return;
}
ch = l2cap->cid[cid];
/* From OPEN go to WAIT_CONFIG_REQ and from WAIT_CONFIG_REQ_RSP to
* WAIT_CONFIG_REQ_RSP. This is assuming the transition chart for OPEN
* on pg 1053, section 6.1.5, volume 3 of BT Core V2.0 has a mistake
* and on options-acceptable we go back to OPEN and otherwise to
* WAIT_CONFIG_REQ and not the other way. */
ch->config &= ~L2CAP_CFG_ACC;
if (l2cap_channel_config(l2cap, ch, flag, data, len))
/* Go to OPEN or WAIT_CONFIG_RSP */
ch->config |= L2CAP_CFG_ACC;
/* TODO: if the incoming traffic flow control or retransmission mode
* changed then we probably need to also generate the
* ConfigureChannel_Req event and set the outgoing traffic to the same
* mode. */
if (!(ch->config & L2CAP_CFG_INIT) && (ch->config & L2CAP_CFG_ACC) &&
!ch->config_req_id)
l2cap_channel_config_req_event(l2cap, ch);
}
static int l2cap_channel_config_rsp_msg(struct l2cap_instance_s *l2cap,
int result, int flag, int cid, const uint8_t *data, int len)
{
struct l2cap_chan_s *ch;
if (unlikely(cid >= L2CAP_CID_MAX || !l2cap->cid[cid])) {
l2cap_command_reject_cid(l2cap, l2cap->last_id, L2CAP_REJ_CID_INVAL,
cid, 0x0000);
return 0;
}
ch = l2cap->cid[cid];
if (ch->config_req_id != l2cap->last_id)
return 1;
ch->config_req_id = 0;
if (result == L2CAP_CONF_SUCCESS) {
if (!flag)
ch->config |= L2CAP_CFG_INIT;
else
l2cap_channel_config_null(l2cap, ch);
} else
/* Retry until we succeed */
l2cap_channel_config_req_event(l2cap, ch);
return 0;
}
static void l2cap_channel_open_req_msg(struct l2cap_instance_s *l2cap,
int psm, int source_cid)
{
struct l2cap_chan_s *ch = l2cap_channel_open(l2cap, psm, source_cid);
if (!ch)
return;
/* Optional */
if (!(ch->config & L2CAP_CFG_INIT) && !ch->config_req_id)
l2cap_channel_config_req_event(l2cap, ch);
}
static void l2cap_info(struct l2cap_instance_s *l2cap, int type)
{
uint8_t data[4];
int len = 0;
int result = L2CAP_IR_SUCCESS;
switch (type) {
case L2CAP_IT_CL_MTU:
data[len ++] = l2cap->group_ch.mps & 0xff;
data[len ++] = l2cap->group_ch.mps >> 8;
break;
case L2CAP_IT_FEAT_MASK:
/* (Prematurely) report Flow control and Retransmission modes. */
data[len ++] = 0x03;
data[len ++] = 0x00;
data[len ++] = 0x00;
data[len ++] = 0x00;
break;
default:
result = L2CAP_IR_NOTSUPP;
}
l2cap_info_response(l2cap, type, result, data, len);
}
static void l2cap_command(struct l2cap_instance_s *l2cap, int code, int id,
const uint8_t *params, int len)
{
int err;
#if 0
/* TODO: do the IDs really have to be in sequence? */
if (!id || (id != l2cap->last_id && id != l2cap->next_id)) {
fprintf(stderr, "%s: out of sequence command packet ignored.\n",
__FUNCTION__);
return;
}
#else
l2cap->next_id = id;
#endif
if (id == l2cap->next_id) {
l2cap->last_id = l2cap->next_id;
l2cap->next_id = l2cap->next_id == 255 ? 1 : l2cap->next_id + 1;
} else {
/* TODO: Need to re-send the same response, without re-executing
* the corresponding command! */
}
switch (code) {
case L2CAP_COMMAND_REJ:
if (unlikely(len != 2 && len != 4 && len != 6)) {
err = L2CAP_REJ_CMD_NOT_UNDERSTOOD;
goto reject;
}
/* We never issue commands other than Command Reject currently. */
fprintf(stderr, "%s: stray Command Reject (%02x, %04x) "
"packet, ignoring.\n", __FUNCTION__, id,
le16_to_cpu(((l2cap_cmd_rej *) params)->reason));
break;
case L2CAP_CONN_REQ:
if (unlikely(len != L2CAP_CONN_REQ_SIZE)) {
err = L2CAP_REJ_CMD_NOT_UNDERSTOOD;
goto reject;
}
l2cap_channel_open_req_msg(l2cap,
le16_to_cpu(((l2cap_conn_req *) params)->psm),
le16_to_cpu(((l2cap_conn_req *) params)->scid));
break;
case L2CAP_CONN_RSP:
if (unlikely(len != L2CAP_CONN_RSP_SIZE)) {
err = L2CAP_REJ_CMD_NOT_UNDERSTOOD;
goto reject;
}
/* We never issue Connection Requests currently. TODO */
fprintf(stderr, "%s: unexpected Connection Response (%02x) "
"packet, ignoring.\n", __FUNCTION__, id);
break;
case L2CAP_CONF_REQ:
if (unlikely(len < L2CAP_CONF_REQ_SIZE(0))) {
err = L2CAP_REJ_CMD_NOT_UNDERSTOOD;
goto reject;
}
l2cap_channel_config_req_msg(l2cap,
le16_to_cpu(((l2cap_conf_req *) params)->flags) & 1,
le16_to_cpu(((l2cap_conf_req *) params)->dcid),
((l2cap_conf_req *) params)->data,
len - L2CAP_CONF_REQ_SIZE(0));
break;
case L2CAP_CONF_RSP:
if (unlikely(len < L2CAP_CONF_RSP_SIZE(0))) {
err = L2CAP_REJ_CMD_NOT_UNDERSTOOD;
goto reject;
}
if (l2cap_channel_config_rsp_msg(l2cap,
le16_to_cpu(((l2cap_conf_rsp *) params)->result),
le16_to_cpu(((l2cap_conf_rsp *) params)->flags) & 1,
le16_to_cpu(((l2cap_conf_rsp *) params)->scid),
((l2cap_conf_rsp *) params)->data,
len - L2CAP_CONF_RSP_SIZE(0)))
fprintf(stderr, "%s: unexpected Configure Response (%02x) "
"packet, ignoring.\n", __FUNCTION__, id);
break;
case L2CAP_DISCONN_REQ:
if (unlikely(len != L2CAP_DISCONN_REQ_SIZE)) {
err = L2CAP_REJ_CMD_NOT_UNDERSTOOD;
goto reject;
}
l2cap_channel_close(l2cap,
le16_to_cpu(((l2cap_disconn_req *) params)->dcid),
le16_to_cpu(((l2cap_disconn_req *) params)->scid));
break;
case L2CAP_DISCONN_RSP:
if (unlikely(len != L2CAP_DISCONN_RSP_SIZE)) {
err = L2CAP_REJ_CMD_NOT_UNDERSTOOD;
goto reject;
}
/* We never issue Disconnection Requests currently. TODO */
fprintf(stderr, "%s: unexpected Disconnection Response (%02x) "
"packet, ignoring.\n", __FUNCTION__, id);
break;
case L2CAP_ECHO_REQ:
l2cap_echo_response(l2cap, params, len);
break;
case L2CAP_ECHO_RSP:
/* We never issue Echo Requests currently. TODO */
fprintf(stderr, "%s: unexpected Echo Response (%02x) "
"packet, ignoring.\n", __FUNCTION__, id);
break;
case L2CAP_INFO_REQ:
if (unlikely(len != L2CAP_INFO_REQ_SIZE)) {
err = L2CAP_REJ_CMD_NOT_UNDERSTOOD;
goto reject;
}
l2cap_info(l2cap, le16_to_cpu(((l2cap_info_req *) params)->type));
break;
case L2CAP_INFO_RSP:
if (unlikely(len != L2CAP_INFO_RSP_SIZE)) {
err = L2CAP_REJ_CMD_NOT_UNDERSTOOD;
goto reject;
}
/* We never issue Information Requests currently. TODO */
fprintf(stderr, "%s: unexpected Information Response (%02x) "
"packet, ignoring.\n", __FUNCTION__, id);
break;
default:
err = L2CAP_REJ_CMD_NOT_UNDERSTOOD;
reject:
l2cap_command_reject(l2cap, id, err, 0, 0);
break;
}
}
static void l2cap_rexmit_enable(struct l2cap_chan_s *ch, int enable)
{
ch->rexmit = enable;
l2cap_retransmission_timer_update(ch);
l2cap_monitor_timer_update(ch);
}
/* Command frame SDU */
static void l2cap_cframe_in(void *opaque, const uint8_t *data, int len)
{
struct l2cap_instance_s *l2cap = opaque;
const l2cap_cmd_hdr *hdr;
int clen;
while (len) {
hdr = (void *) data;
if (len < L2CAP_CMD_HDR_SIZE)
/* TODO: signal an error */
return;
len -= L2CAP_CMD_HDR_SIZE;
data += L2CAP_CMD_HDR_SIZE;
clen = le16_to_cpu(hdr->len);
if (len < clen) {
l2cap_command_reject(l2cap, hdr->ident,
L2CAP_REJ_CMD_NOT_UNDERSTOOD, 0, 0);
break;
}
l2cap_command(l2cap, hdr->code, hdr->ident, data, clen);
len -= clen;
data += clen;
}
}
/* Group frame SDU */
static void l2cap_gframe_in(void *opaque, const uint8_t *data, int len)
{
}
/* Supervisory frame */
static void l2cap_sframe_in(struct l2cap_chan_s *ch, uint16_t ctrl)
{
}
/* Basic L2CAP mode Information frame */
static void l2cap_bframe_in(struct l2cap_chan_s *ch, uint16_t cid,
const l2cap_hdr *hdr, int len)
{
/* We have a full SDU, no further processing */
ch->params.sdu_in(ch->params.opaque, hdr->data, len);
}
/* Flow Control and Retransmission mode frame */
static void l2cap_iframe_in(struct l2cap_chan_s *ch, uint16_t cid,
const l2cap_hdr *hdr, int len)
{
uint16_t fcs = le16_to_cpup((void *) (hdr->data + len - 2));
if (len < 4)
goto len_error;
if (l2cap_fcs16((const uint8_t *) hdr, L2CAP_HDR_SIZE + len - 2) != fcs)
goto fcs_error;
if ((hdr->data[0] >> 7) == ch->rexmit)
l2cap_rexmit_enable(ch, !(hdr->data[0] >> 7));
if (hdr->data[0] & 1) {
if (len != 4) {
/* TODO: Signal an error? */
return;
}
l2cap_sframe_in(ch, le16_to_cpup((void *) hdr->data));
return;
}
switch (hdr->data[1] >> 6) { /* SAR */
case L2CAP_SAR_NO_SEG:
if (ch->len_total)
goto seg_error;
if (len - 4 > ch->mps)
goto len_error;
ch->params.sdu_in(ch->params.opaque, hdr->data + 2, len - 4);
break;
case L2CAP_SAR_START:
if (ch->len_total || len < 6)
goto seg_error;
if (len - 6 > ch->mps)
goto len_error;
ch->len_total = le16_to_cpup((void *) (hdr->data + 2));
if (len >= 6 + ch->len_total)
goto seg_error;
ch->len_cur = len - 6;
memcpy(ch->sdu, hdr->data + 4, ch->len_cur);
break;
case L2CAP_SAR_END:
if (!ch->len_total || ch->len_cur + len - 4 < ch->len_total)
goto seg_error;
if (len - 4 > ch->mps)
goto len_error;
memcpy(ch->sdu + ch->len_cur, hdr->data + 2, len - 4);
ch->params.sdu_in(ch->params.opaque, ch->sdu, ch->len_total);
break;
case L2CAP_SAR_CONT:
if (!ch->len_total || ch->len_cur + len - 4 >= ch->len_total)
goto seg_error;
if (len - 4 > ch->mps)
goto len_error;
memcpy(ch->sdu + ch->len_cur, hdr->data + 2, len - 4);
ch->len_cur += len - 4;
break;
seg_error:
len_error: /* TODO */
fcs_error: /* TODO */
ch->len_cur = 0;
ch->len_total = 0;
break;
}
}
static void l2cap_frame_in(struct l2cap_instance_s *l2cap,
const l2cap_hdr *frame)
{
uint16_t cid = le16_to_cpu(frame->cid);
uint16_t len = le16_to_cpu(frame->len);
if (unlikely(cid >= L2CAP_CID_MAX || !l2cap->cid[cid])) {
fprintf(stderr, "%s: frame addressed to a non-existent L2CAP "
"channel %04x received.\n", __FUNCTION__, cid);
return;
}
l2cap->cid[cid]->frame_in(l2cap->cid[cid], cid, frame, len);
}
/* "Recombination" */
static void l2cap_pdu_in(struct l2cap_instance_s *l2cap,
const uint8_t *data, int len)
{
const l2cap_hdr *hdr = (void *) l2cap->frame_in;
if (unlikely(len + l2cap->frame_in_len > sizeof(l2cap->frame_in))) {
if (l2cap->frame_in_len < sizeof(l2cap->frame_in)) {
memcpy(l2cap->frame_in + l2cap->frame_in_len, data,
sizeof(l2cap->frame_in) - l2cap->frame_in_len);
l2cap->frame_in_len = sizeof(l2cap->frame_in);
/* TODO: truncate */
l2cap_frame_in(l2cap, hdr);
}
return;
}
memcpy(l2cap->frame_in + l2cap->frame_in_len, data, len);
l2cap->frame_in_len += len;
if (len >= L2CAP_HDR_SIZE)
if (len >= L2CAP_HDR_SIZE + le16_to_cpu(hdr->len))
l2cap_frame_in(l2cap, hdr);
/* There is never a start of a new PDU in the same ACL packet, so
* no need to memmove the remaining payload and loop. */
}
static inline uint8_t *l2cap_pdu_out(struct l2cap_instance_s *l2cap,
uint16_t cid, uint16_t len)
{
l2cap_hdr *hdr = (void *) l2cap->frame_out;
l2cap->frame_out_len = len + L2CAP_HDR_SIZE;
hdr->cid = cpu_to_le16(cid);
hdr->len = cpu_to_le16(len);
return l2cap->frame_out + L2CAP_HDR_SIZE;
}
static inline void l2cap_pdu_submit(struct l2cap_instance_s *l2cap)
{
/* TODO: Fragmentation */
(l2cap->role ?
l2cap->link->slave->lmp_acl_data : l2cap->link->host->lmp_acl_resp)
(l2cap->link, l2cap->frame_out, 1, l2cap->frame_out_len);
}
static uint8_t *l2cap_bframe_out(struct bt_l2cap_conn_params_s *parm, int len)
{
struct l2cap_chan_s *chan = (struct l2cap_chan_s *) parm;
if (len > chan->params.remote_mtu) {
fprintf(stderr, "%s: B-Frame for CID %04x longer than %i octets.\n",
__FUNCTION__,
chan->remote_cid, chan->params.remote_mtu);
exit(-1);
}
return l2cap_pdu_out(chan->l2cap, chan->remote_cid, len);
}
static void l2cap_bframe_submit(struct bt_l2cap_conn_params_s *parms)
{
struct l2cap_chan_s *chan = (struct l2cap_chan_s *) parms;
l2cap_pdu_submit(chan->l2cap);
}
#if 0
/* Stub: Only used if an emulated device requests outgoing flow control */
static uint8_t *l2cap_iframe_out(struct bt_l2cap_conn_params_s *parm, int len)
{
struct l2cap_chan_s *chan = (struct l2cap_chan_s *) parm;
if (len > chan->params.remote_mtu) {
/* TODO: slice into segments and queue each segment as a separate
* I-Frame in a FIFO of I-Frames, local to the CID. */
} else {
/* TODO: add to the FIFO of I-Frames, local to the CID. */
/* Possibly we need to return a pointer to a contiguous buffer
* for now and then memcpy from it into FIFOs in l2cap_iframe_submit
* while segmenting at the same time. */
}
return 0;
}
static void l2cap_iframe_submit(struct bt_l2cap_conn_params_s *parm)
{
/* TODO: If flow control indicates clear to send, start submitting the
* invidual I-Frames from the FIFO, but don't remove them from there.
* Kick the appropriate timer until we get an S-Frame, and only then
* remove from FIFO or resubmit and re-kick the timer if the timer
* expired. */
}
#endif
static void l2cap_init(struct l2cap_instance_s *l2cap,
struct bt_link_s *link, int role)
{
l2cap->link = link;
l2cap->role = role;
l2cap->dev = (struct bt_l2cap_device_s *)
(role ? link->host : link->slave);
l2cap->next_id = 1;
/* Establish the signalling channel */
l2cap->signalling_ch.params.sdu_in = l2cap_cframe_in;
l2cap->signalling_ch.params.sdu_out = l2cap_bframe_out;
l2cap->signalling_ch.params.sdu_submit = l2cap_bframe_submit;
l2cap->signalling_ch.params.opaque = l2cap;
l2cap->signalling_ch.params.remote_mtu = 48;
l2cap->signalling_ch.remote_cid = L2CAP_CID_SIGNALLING;
l2cap->signalling_ch.frame_in = l2cap_bframe_in;
l2cap->signalling_ch.mps = 65536;
l2cap->signalling_ch.min_mtu = 48;
l2cap->signalling_ch.mode = L2CAP_MODE_BASIC;
l2cap->signalling_ch.l2cap = l2cap;
l2cap->cid[L2CAP_CID_SIGNALLING] = &l2cap->signalling_ch;
/* Establish the connection-less data channel */
l2cap->group_ch.params.sdu_in = l2cap_gframe_in;
l2cap->group_ch.params.opaque = l2cap;
l2cap->group_ch.frame_in = l2cap_bframe_in;
l2cap->group_ch.mps = 65533;
l2cap->group_ch.l2cap = l2cap;
l2cap->group_ch.remote_cid = L2CAP_CID_INVALID;
l2cap->cid[L2CAP_CID_GROUP] = &l2cap->group_ch;
}
static void l2cap_teardown(struct l2cap_instance_s *l2cap, int send_disconnect)
{
int cid;
/* Don't send DISCONNECT if we are currently handling a DISCONNECT
* sent from the other side. */
if (send_disconnect) {
if (l2cap->role)
l2cap->dev->device.lmp_disconnect_slave(l2cap->link);
/* l2cap->link is invalid from now on. */
else
l2cap->dev->device.lmp_disconnect_master(l2cap->link);
}
for (cid = L2CAP_CID_ALLOC; cid < L2CAP_CID_MAX; cid ++)
if (l2cap->cid[cid]) {
l2cap->cid[cid]->params.close(l2cap->cid[cid]->params.opaque);
g_free(l2cap->cid[cid]);
}
if (l2cap->role)
g_free(l2cap);
else
g_free(l2cap->link);
}
/* L2CAP glue to lower layers in bluetooth stack (LMP) */
static void l2cap_lmp_connection_request(struct bt_link_s *link)
{
struct bt_l2cap_device_s *dev = (struct bt_l2cap_device_s *) link->slave;
struct slave_l2cap_instance_s *l2cap;
/* Always accept - we only get called if (dev->device->page_scan). */
l2cap = g_malloc0(sizeof(struct slave_l2cap_instance_s));
l2cap->link.slave = &dev->device;
l2cap->link.host = link->host;
l2cap_init(&l2cap->l2cap, &l2cap->link, 0);
/* Always at the end */
link->host->reject_reason = 0;
link->host->lmp_connection_complete(&l2cap->link);
}
/* Stub */
static void l2cap_lmp_connection_complete(struct bt_link_s *link)
{
struct bt_l2cap_device_s *dev = (struct bt_l2cap_device_s *) link->host;
struct l2cap_instance_s *l2cap;
if (dev->device.reject_reason) {
/* Signal to upper layer */
return;
}
l2cap = g_malloc0(sizeof(struct l2cap_instance_s));
l2cap_init(l2cap, link, 1);
link->acl_mode = acl_active;
/* Signal to upper layer */
}
/* Stub */
static void l2cap_lmp_disconnect_host(struct bt_link_s *link)
{
struct bt_l2cap_device_s *dev = (struct bt_l2cap_device_s *) link->host;
struct l2cap_instance_s *l2cap =
/* TODO: Retrieve from upper layer */ (void *) dev;
/* Signal to upper layer */
l2cap_teardown(l2cap, 0);
}
static void l2cap_lmp_disconnect_slave(struct bt_link_s *link)
{
struct slave_l2cap_instance_s *l2cap =
(struct slave_l2cap_instance_s *) link;
l2cap_teardown(&l2cap->l2cap, 0);
}
static void l2cap_lmp_acl_data_slave(struct bt_link_s *link,
const uint8_t *data, int start, int len)
{
struct slave_l2cap_instance_s *l2cap =
(struct slave_l2cap_instance_s *) link;
if (start)
l2cap->l2cap.frame_in_len = 0;
l2cap_pdu_in(&l2cap->l2cap, data, len);
}
/* Stub */
static void l2cap_lmp_acl_data_host(struct bt_link_s *link,
const uint8_t *data, int start, int len)
{
struct bt_l2cap_device_s *dev = (struct bt_l2cap_device_s *) link->host;
struct l2cap_instance_s *l2cap =
/* TODO: Retrieve from upper layer */ (void *) dev;
if (start)
l2cap->frame_in_len = 0;
l2cap_pdu_in(l2cap, data, len);
}
static void l2cap_dummy_destroy(struct bt_device_s *dev)
{
struct bt_l2cap_device_s *l2cap_dev = (struct bt_l2cap_device_s *) dev;
bt_l2cap_device_done(l2cap_dev);
}
void bt_l2cap_device_init(struct bt_l2cap_device_s *dev,
struct bt_scatternet_s *net)
{
bt_device_init(&dev->device, net);
dev->device.lmp_connection_request = l2cap_lmp_connection_request;
dev->device.lmp_connection_complete = l2cap_lmp_connection_complete;
dev->device.lmp_disconnect_master = l2cap_lmp_disconnect_host;
dev->device.lmp_disconnect_slave = l2cap_lmp_disconnect_slave;
dev->device.lmp_acl_data = l2cap_lmp_acl_data_slave;
dev->device.lmp_acl_resp = l2cap_lmp_acl_data_host;
dev->device.handle_destroy = l2cap_dummy_destroy;
}
void bt_l2cap_device_done(struct bt_l2cap_device_s *dev)
{
bt_device_done(&dev->device);
/* Should keep a list of all instances and go through it and
* invoke l2cap_teardown() for each. */
}
void bt_l2cap_psm_register(struct bt_l2cap_device_s *dev, int psm, int min_mtu,
int (*new_channel)(struct bt_l2cap_device_s *dev,
struct bt_l2cap_conn_params_s *params))
{
struct bt_l2cap_psm_s *new_psm = l2cap_psm(dev, psm);
if (new_psm) {
fprintf(stderr, "%s: PSM %04x already registered for device `%s'.\n",
__FUNCTION__, psm, dev->device.lmp_name);
exit(-1);
}
new_psm = g_malloc0(sizeof(*new_psm));
new_psm->psm = psm;
new_psm->min_mtu = min_mtu;
new_psm->new_channel = new_channel;
new_psm->next = dev->first_psm;
dev->first_psm = new_psm;
}
