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NetBSD/sys/netbt/l2cap_signal.c

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/* $NetBSD: l2cap_signal.c,v 1.10 2009/09/25 19:44:57 plunky Exp $ */
/*-
* Copyright (c) 2005 Iain Hibbert.
* Copyright (c) 2006 Itronix Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of Itronix Inc. may not be used to endorse
* or promote products derived from this software without specific
* prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY ITRONIX INC. ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL ITRONIX INC. BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: l2cap_signal.c,v 1.10 2009/09/25 19:44:57 plunky Exp $");
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/mbuf.h>
#include <sys/proc.h>
#include <sys/queue.h>
#include <sys/systm.h>
#include <machine/stdarg.h>
#include <netbt/bluetooth.h>
#include <netbt/hci.h>
#include <netbt/l2cap.h>
/*******************************************************************************
*
* L2CAP Signal processing
*/
static void l2cap_recv_command_rej(struct mbuf *, struct hci_link *);
static void l2cap_recv_connect_req(struct mbuf *, struct hci_link *);
static void l2cap_recv_connect_rsp(struct mbuf *, struct hci_link *);
static void l2cap_recv_config_req(struct mbuf *, struct hci_link *);
static void l2cap_recv_config_rsp(struct mbuf *, struct hci_link *);
static void l2cap_recv_disconnect_req(struct mbuf *, struct hci_link *);
static void l2cap_recv_disconnect_rsp(struct mbuf *, struct hci_link *);
static void l2cap_recv_info_req(struct mbuf *, struct hci_link *);
static int l2cap_send_signal(struct hci_link *, uint8_t, uint8_t, uint16_t, void *);
static int l2cap_send_command_rej(struct hci_link *, uint8_t, uint16_t, ...);
/*
* process incoming signal packets (CID 0x0001). Can contain multiple
* requests/responses.
*/
void
l2cap_recv_signal(struct mbuf *m, struct hci_link *link)
{
l2cap_cmd_hdr_t cmd;
for(;;) {
if (m->m_pkthdr.len == 0)
goto finish;
if (m->m_pkthdr.len < sizeof(cmd))
goto reject;
m_copydata(m, 0, sizeof(cmd), &cmd);
cmd.length = le16toh(cmd.length);
if (m->m_pkthdr.len < sizeof(cmd) + cmd.length)
goto reject;
DPRINTFN(2, "(%s) code %d, ident %d, len %d\n",
device_xname(link->hl_unit->hci_dev),
cmd.code, cmd.ident, cmd.length);
switch (cmd.code) {
case L2CAP_COMMAND_REJ:
if (cmd.length > sizeof(l2cap_cmd_rej_cp))
goto finish;
l2cap_recv_command_rej(m, link);
break;
case L2CAP_CONNECT_REQ:
if (cmd.length != sizeof(l2cap_con_req_cp))
goto reject;
l2cap_recv_connect_req(m, link);
break;
case L2CAP_CONNECT_RSP:
if (cmd.length != sizeof(l2cap_con_rsp_cp))
goto finish;
l2cap_recv_connect_rsp(m, link);
break;
case L2CAP_CONFIG_REQ:
l2cap_recv_config_req(m, link);
break;
case L2CAP_CONFIG_RSP:
l2cap_recv_config_rsp(m, link);
break;
case L2CAP_DISCONNECT_REQ:
if (cmd.length != sizeof(l2cap_discon_req_cp))
goto reject;
l2cap_recv_disconnect_req(m, link);
break;
case L2CAP_DISCONNECT_RSP:
if (cmd.length != sizeof(l2cap_discon_rsp_cp))
goto finish;
l2cap_recv_disconnect_rsp(m, link);
break;
case L2CAP_ECHO_REQ:
m_adj(m, sizeof(cmd) + cmd.length);
l2cap_send_signal(link, L2CAP_ECHO_RSP, cmd.ident,
0, NULL);
break;
case L2CAP_ECHO_RSP:
m_adj(m, sizeof(cmd) + cmd.length);
break;
case L2CAP_INFO_REQ:
if (cmd.length != sizeof(l2cap_info_req_cp))
goto reject;
l2cap_recv_info_req(m, link);
break;
case L2CAP_INFO_RSP:
m_adj(m, sizeof(cmd) + cmd.length);
break;
default:
goto reject;
}
}
#ifdef DIAGNOSTIC
panic("impossible!");
#endif
reject:
l2cap_send_command_rej(link, cmd.ident, L2CAP_REJ_NOT_UNDERSTOOD);
finish:
m_freem(m);
}
/*
* Process Received Command Reject. For now we dont try to recover gracefully
* from this, it probably means that the link is garbled or the other end is
* insufficiently capable of handling normal traffic. (not *my* fault, no way!)
*/
static void
l2cap_recv_command_rej(struct mbuf *m, struct hci_link *link)
{
struct l2cap_req *req;
struct l2cap_channel *chan;
l2cap_cmd_hdr_t cmd;
l2cap_cmd_rej_cp cp;
m_copydata(m, 0, sizeof(cmd), &cmd);
m_adj(m, sizeof(cmd));
cmd.length = le16toh(cmd.length);
m_copydata(m, 0, cmd.length, &cp);
m_adj(m, cmd.length);
req = l2cap_request_lookup(link, cmd.ident);
if (req == NULL)
return;
switch (le16toh(cp.reason)) {
case L2CAP_REJ_NOT_UNDERSTOOD:
/*
* I dont know what to do, just move up the timeout
*/
callout_schedule(&req->lr_rtx, 0);
break;
case L2CAP_REJ_MTU_EXCEEDED:
/*
* I didnt send any commands over L2CAP_MTU_MINIMUM size, but..
*
* XXX maybe we should resend this, instead?
*/
link->hl_mtu = le16toh(cp.data[0]);
callout_schedule(&req->lr_rtx, 0);
break;
case L2CAP_REJ_INVALID_CID:
/*
* Well, if they dont have such a channel then our channel is
* most likely closed. Make it so.
*/
chan = req->lr_chan;
l2cap_request_free(req);
if (chan != NULL && chan->lc_state != L2CAP_CLOSED)
l2cap_close(chan, ECONNABORTED);
break;
default:
UNKNOWN(le16toh(cp.reason));
break;
}
}
/*
* Process Received Connect Request. Find listening channel matching
* psm & addr and ask upper layer for a new channel.
*/
static void
l2cap_recv_connect_req(struct mbuf *m, struct hci_link *link)
{
struct sockaddr_bt laddr, raddr;
struct l2cap_channel *chan, *new;
l2cap_cmd_hdr_t cmd;
l2cap_con_req_cp cp;
int err;
/* extract cmd */
m_copydata(m, 0, sizeof(cmd), &cmd);
m_adj(m, sizeof(cmd));
/* extract request */
m_copydata(m, 0, sizeof(cp), &cp);
m_adj(m, sizeof(cp));
cp.scid = le16toh(cp.scid);
cp.psm = le16toh(cp.psm);
memset(&laddr, 0, sizeof(struct sockaddr_bt));
laddr.bt_len = sizeof(struct sockaddr_bt);
laddr.bt_family = AF_BLUETOOTH;
laddr.bt_psm = cp.psm;
bdaddr_copy(&laddr.bt_bdaddr, &link->hl_unit->hci_bdaddr);
memset(&raddr, 0, sizeof(struct sockaddr_bt));
raddr.bt_len = sizeof(struct sockaddr_bt);
raddr.bt_family = AF_BLUETOOTH;
raddr.bt_psm = cp.psm;
bdaddr_copy(&raddr.bt_bdaddr, &link->hl_bdaddr);
LIST_FOREACH(chan, &l2cap_listen_list, lc_ncid) {
if (chan->lc_laddr.bt_psm != laddr.bt_psm)
continue;
if (!bdaddr_same(&laddr.bt_bdaddr, &chan->lc_laddr.bt_bdaddr)
&& bdaddr_any(&chan->lc_laddr.bt_bdaddr) == 0)
continue;
new= (*chan->lc_proto->newconn)(chan->lc_upper, &laddr, &raddr);
if (new == NULL)
continue;
err = l2cap_cid_alloc(new);
if (err) {
l2cap_send_connect_rsp(link, cmd.ident,
0, cp.scid,
L2CAP_NO_RESOURCES);
(*new->lc_proto->disconnected)(new->lc_upper, err);
return;
}
new->lc_link = hci_acl_open(link->hl_unit, &link->hl_bdaddr);
KASSERT(new->lc_link == link);
new->lc_rcid = cp.scid;
new->lc_ident = cmd.ident;
memcpy(&new->lc_laddr, &laddr, sizeof(struct sockaddr_bt));
memcpy(&new->lc_raddr, &raddr, sizeof(struct sockaddr_bt));
new->lc_mode = chan->lc_mode;
err = l2cap_setmode(new);
if (err == EINPROGRESS) {
new->lc_state = L2CAP_WAIT_SEND_CONNECT_RSP;
(*new->lc_proto->connecting)(new->lc_upper);
return;
}
if (err) {
new->lc_state = L2CAP_CLOSED;
hci_acl_close(link, err);
new->lc_link = NULL;
l2cap_send_connect_rsp(link, cmd.ident,
0, cp.scid,
L2CAP_NO_RESOURCES);
(*new->lc_proto->disconnected)(new->lc_upper, err);
return;
}
err = l2cap_send_connect_rsp(link, cmd.ident,
new->lc_lcid, new->lc_rcid,
L2CAP_SUCCESS);
if (err) {
l2cap_close(new, err);
return;
}
new->lc_state = L2CAP_WAIT_CONFIG;
new->lc_flags |= (L2CAP_WAIT_CONFIG_REQ | L2CAP_WAIT_CONFIG_RSP);
err = l2cap_send_config_req(new);
if (err)
l2cap_close(new, err);
return;
}
l2cap_send_connect_rsp(link, cmd.ident,
0, cp.scid,
L2CAP_PSM_NOT_SUPPORTED);
}
/*
* Process Received Connect Response.
*/
static void
l2cap_recv_connect_rsp(struct mbuf *m, struct hci_link *link)
{
l2cap_cmd_hdr_t cmd;
l2cap_con_rsp_cp cp;
struct l2cap_req *req;
struct l2cap_channel *chan;
m_copydata(m, 0, sizeof(cmd), &cmd);
m_adj(m, sizeof(cmd));
m_copydata(m, 0, sizeof(cp), &cp);
m_adj(m, sizeof(cp));
cp.scid = le16toh(cp.scid);
cp.dcid = le16toh(cp.dcid);
cp.result = le16toh(cp.result);
req = l2cap_request_lookup(link, cmd.ident);
if (req == NULL || req->lr_code != L2CAP_CONNECT_REQ)
return;
chan = req->lr_chan;
if (chan != NULL && chan->lc_lcid != cp.scid)
return;
if (chan == NULL || chan->lc_state != L2CAP_WAIT_RECV_CONNECT_RSP) {
l2cap_request_free(req);
return;
}
switch (cp.result) {
case L2CAP_SUCCESS:
/*
* Ok, at this point we have a connection to the other party. We
* could indicate upstream that we are ready for business and
* wait for a "Configure Channel Request" but I'm not so sure
* that is required in our case - we will proceed directly to
* sending our config request. We set two state bits because in
* the config state we are waiting for requests and responses.
*/
l2cap_request_free(req);
chan->lc_rcid = cp.dcid;
chan->lc_state = L2CAP_WAIT_CONFIG;
chan->lc_flags |= (L2CAP_WAIT_CONFIG_REQ | L2CAP_WAIT_CONFIG_RSP);
l2cap_send_config_req(chan);
break;
case L2CAP_PENDING:
/* XXX dont release request, should start eRTX timeout? */
(*chan->lc_proto->connecting)(chan->lc_upper);
break;
case L2CAP_PSM_NOT_SUPPORTED:
case L2CAP_SECURITY_BLOCK:
case L2CAP_NO_RESOURCES:
default:
l2cap_request_free(req);
l2cap_close(chan, ECONNREFUSED);
break;
}
}
/*
* Process Received Config Reqest.
*/
static void
l2cap_recv_config_req(struct mbuf *m, struct hci_link *link)
{
uint8_t buf[L2CAP_MTU_MINIMUM];
l2cap_cmd_hdr_t cmd;
l2cap_cfg_req_cp cp;
l2cap_cfg_opt_t opt;
l2cap_cfg_opt_val_t val;
l2cap_cfg_rsp_cp rp;
struct l2cap_channel *chan;
int left, len;
m_copydata(m, 0, sizeof(cmd), &cmd);
m_adj(m, sizeof(cmd));
left = le16toh(cmd.length);
if (left < sizeof(cp))
goto reject;
m_copydata(m, 0, sizeof(cp), &cp);
m_adj(m, sizeof(cp));
left -= sizeof(cp);
cp.dcid = le16toh(cp.dcid);
cp.flags = le16toh(cp.flags);
chan = l2cap_cid_lookup(cp.dcid);
if (chan == NULL || chan->lc_link != link
|| chan->lc_state != L2CAP_WAIT_CONFIG
|| (chan->lc_flags & L2CAP_WAIT_CONFIG_REQ) == 0) {
/* XXX we should really accept reconfiguration requests */
l2cap_send_command_rej(link, cmd.ident, L2CAP_REJ_INVALID_CID,
L2CAP_NULL_CID, cp.dcid);
goto out;
}
/* ready our response packet */
rp.scid = htole16(chan->lc_rcid);
rp.flags = 0; /* "No Continuation" */
rp.result = L2CAP_SUCCESS;
len = sizeof(rp);
/*
* Process the packet. We build the return packet on the fly adding any
* unacceptable parameters as we go. As we can only return one result,
* unknown option takes precedence so we start our return packet anew
* and ignore option values thereafter as they will be re-sent.
*
* Since we do not support enough options to make overflowing the min
* MTU size an issue in normal use, we just reject config requests that
* make that happen. This could be because options are repeated or the
* packet is corrupted in some way.
*
* If unknown option types threaten to overflow the packet, we just
* ignore them. We can deny them next time.
*/
while (left > 0) {
if (left < sizeof(opt))
goto reject;
m_copydata(m, 0, sizeof(opt), &opt);
m_adj(m, sizeof(opt));
left -= sizeof(opt);
if (left < opt.length)
goto reject;
switch(opt.type & L2CAP_OPT_HINT_MASK) {
case L2CAP_OPT_MTU:
if (rp.result == L2CAP_UNKNOWN_OPTION)
break;
if (opt.length != L2CAP_OPT_MTU_SIZE)
goto reject;
m_copydata(m, 0, L2CAP_OPT_MTU_SIZE, &val);
val.mtu = le16toh(val.mtu);
/*
* XXX how do we know what the minimum acceptable MTU is
* for a channel? Spec says some profiles have a higher
* minimum but I have no way to find that out at this
* juncture..
*/
if (val.mtu < L2CAP_MTU_MINIMUM) {
if (len + sizeof(opt) + L2CAP_OPT_MTU_SIZE > sizeof(buf))
goto reject;
rp.result = L2CAP_UNACCEPTABLE_PARAMS;
memcpy(buf + len, &opt, sizeof(opt));
len += sizeof(opt);
val.mtu = htole16(L2CAP_MTU_MINIMUM);
memcpy(buf + len, &val, L2CAP_OPT_MTU_SIZE);
len += L2CAP_OPT_MTU_SIZE;
} else
chan->lc_omtu = val.mtu;
break;
case L2CAP_OPT_FLUSH_TIMO:
if (rp.result == L2CAP_UNKNOWN_OPTION)
break;
if (opt.length != L2CAP_OPT_FLUSH_TIMO_SIZE)
goto reject;
/*
* I think that this is informational only - he is
* informing us of the flush timeout he will be using.
* I dont think this affects us in any significant way,
* so just ignore this value for now.
*/
break;
case L2CAP_OPT_QOS:
default:
/* ignore hints */
if (opt.type & L2CAP_OPT_HINT_BIT)
break;
/* unknown options supercede all else */
if (rp.result != L2CAP_UNKNOWN_OPTION) {
rp.result = L2CAP_UNKNOWN_OPTION;
len = sizeof(rp);
}
/* ignore if it don't fit */
if (len + sizeof(opt) > sizeof(buf))
break;
/* return unknown option type, but no data */
buf[len++] = opt.type;
buf[len++] = 0;
break;
}
m_adj(m, opt.length);
left -= opt.length;
}
rp.result = htole16(rp.result);
memcpy(buf, &rp, sizeof(rp));
l2cap_send_signal(link, L2CAP_CONFIG_RSP, cmd.ident, len, buf);
if ((cp.flags & L2CAP_OPT_CFLAG_BIT) == 0
&& rp.result == le16toh(L2CAP_SUCCESS)) {
chan->lc_flags &= ~L2CAP_WAIT_CONFIG_REQ;
if ((chan->lc_flags & L2CAP_WAIT_CONFIG_RSP) == 0) {
chan->lc_state = L2CAP_OPEN;
/* XXX how to distinguish REconfiguration? */
(*chan->lc_proto->connected)(chan->lc_upper);
}
}
return;
reject:
l2cap_send_command_rej(link, cmd.ident, L2CAP_REJ_NOT_UNDERSTOOD);
out:
m_adj(m, left);
}
/*
* Process Received Config Response.
*/
static void
l2cap_recv_config_rsp(struct mbuf *m, struct hci_link *link)
{
l2cap_cmd_hdr_t cmd;
l2cap_cfg_rsp_cp cp;
l2cap_cfg_opt_t opt;
l2cap_cfg_opt_val_t val;
struct l2cap_req *req;
struct l2cap_channel *chan;
int left;
m_copydata(m, 0, sizeof(cmd), &cmd);
m_adj(m, sizeof(cmd));
left = le16toh(cmd.length);
if (left < sizeof(cp))
goto out;
m_copydata(m, 0, sizeof(cp), &cp);
m_adj(m, sizeof(cp));
left -= sizeof(cp);
cp.scid = le16toh(cp.scid);
cp.flags = le16toh(cp.flags);
cp.result = le16toh(cp.result);
req = l2cap_request_lookup(link, cmd.ident);
if (req == NULL || req->lr_code != L2CAP_CONFIG_REQ)
goto out;
chan = req->lr_chan;
if (chan != NULL && chan->lc_lcid != cp.scid)
goto out;
l2cap_request_free(req);
if (chan == NULL || chan->lc_state != L2CAP_WAIT_CONFIG
|| (chan->lc_flags & L2CAP_WAIT_CONFIG_RSP) == 0)
goto out;
if ((cp.flags & L2CAP_OPT_CFLAG_BIT)) {
l2cap_cfg_req_cp rp;
/*
* They have more to tell us and want another ID to
* use, so send an empty config request
*/
if (l2cap_request_alloc(chan, L2CAP_CONFIG_REQ))
goto discon;
rp.dcid = htole16(cp.scid);
rp.flags = 0;
if (l2cap_send_signal(link, L2CAP_CONFIG_REQ, link->hl_lastid,
sizeof(rp), &rp))
goto discon;
}
switch(cp.result) {
case L2CAP_SUCCESS:
/*
* If continuation flag was not set, our config request was
* accepted. We may have to wait for their config request to
* complete, so check that but otherwise we are open
*
* There may be 'advisory' values in the packet but we just
* ignore those..
*/
if ((cp.flags & L2CAP_OPT_CFLAG_BIT) == 0) {
chan->lc_flags &= ~L2CAP_WAIT_CONFIG_RSP;
if ((chan->lc_flags & L2CAP_WAIT_CONFIG_REQ) == 0) {
chan->lc_state = L2CAP_OPEN;
/* XXX how to distinguish REconfiguration? */
(*chan->lc_proto->connected)(chan->lc_upper);
}
}
goto out;
case L2CAP_UNACCEPTABLE_PARAMS:
/*
* Packet contains unacceptable parameters with preferred values
*/
while (left > 0) {
if (left < sizeof(opt))
goto discon;
m_copydata(m, 0, sizeof(opt), &opt);
m_adj(m, sizeof(opt));
left -= sizeof(opt);
if (left < opt.length)
goto discon;
switch (opt.type) {
case L2CAP_OPT_MTU:
if (opt.length != L2CAP_OPT_MTU_SIZE)
goto discon;
m_copydata(m, 0, L2CAP_OPT_MTU_SIZE, &val);
chan->lc_imtu = le16toh(val.mtu);
if (chan->lc_imtu < L2CAP_MTU_MINIMUM)
chan->lc_imtu = L2CAP_MTU_DEFAULT;
break;
case L2CAP_OPT_FLUSH_TIMO:
if (opt.length != L2CAP_OPT_FLUSH_TIMO_SIZE)
goto discon;
/*
* Spec says: If we cannot honor proposed value,
* either disconnect or try again with original
* value. I can't really see why they want to
* interfere with OUR flush timeout in any case
* so we just punt for now.
*/
goto discon;
case L2CAP_OPT_QOS:
break;
default:
UNKNOWN(opt.type);
goto discon;
}
m_adj(m, opt.length);
left -= opt.length;
}
if ((cp.flags & L2CAP_OPT_CFLAG_BIT) == 0)
l2cap_send_config_req(chan); /* no state change */
goto out;
case L2CAP_REJECT:
goto discon;
case L2CAP_UNKNOWN_OPTION:
/*
* Packet contains options not understood. Turn off unknown
* options by setting them to default values (means they will
* not be requested again).
*
* If our option was already off then fail (paranoia?)
*
* XXX Should we consider that options were set for a reason?
*/
while (left > 0) {
if (left < sizeof(opt))
goto discon;
m_copydata(m, 0, sizeof(opt), &opt);
m_adj(m, sizeof(opt));
left -= sizeof(opt);
if (left < opt.length)
goto discon;
m_adj(m, opt.length);
left -= opt.length;
switch(opt.type) {
case L2CAP_OPT_MTU:
if (chan->lc_imtu == L2CAP_MTU_DEFAULT)
goto discon;
chan->lc_imtu = L2CAP_MTU_DEFAULT;
break;
case L2CAP_OPT_FLUSH_TIMO:
if (chan->lc_flush == L2CAP_FLUSH_TIMO_DEFAULT)
goto discon;
chan->lc_flush = L2CAP_FLUSH_TIMO_DEFAULT;
break;
case L2CAP_OPT_QOS:
break;
default:
UNKNOWN(opt.type);
goto discon;
}
}
if ((cp.flags & L2CAP_OPT_CFLAG_BIT) == 0)
l2cap_send_config_req(chan); /* no state change */
goto out;
default:
UNKNOWN(cp.result);
goto discon;
}
DPRINTF("how did I get here!?\n");
discon:
l2cap_send_disconnect_req(chan);
l2cap_close(chan, ECONNABORTED);
out:
m_adj(m, left);
}
/*
* Process Received Disconnect Request. We must validate scid and dcid
* just in case but otherwise this connection is finished.
*/
static void
l2cap_recv_disconnect_req(struct mbuf *m, struct hci_link *link)
{
l2cap_cmd_hdr_t cmd;
l2cap_discon_req_cp cp;
l2cap_discon_rsp_cp rp;
struct l2cap_channel *chan;
m_copydata(m, 0, sizeof(cmd), &cmd);
m_adj(m, sizeof(cmd));
m_copydata(m, 0, sizeof(cp), &cp);
m_adj(m, sizeof(cp));
cp.scid = le16toh(cp.scid);
cp.dcid = le16toh(cp.dcid);
chan = l2cap_cid_lookup(cp.dcid);
if (chan == NULL || chan->lc_link != link || chan->lc_rcid != cp.scid) {
l2cap_send_command_rej(link, cmd.ident, L2CAP_REJ_INVALID_CID,
cp.dcid, cp.scid);
return;
}
rp.dcid = htole16(chan->lc_lcid);
rp.scid = htole16(chan->lc_rcid);
l2cap_send_signal(link, L2CAP_DISCONNECT_RSP, cmd.ident,
sizeof(rp), &rp);
if (chan->lc_state != L2CAP_CLOSED)
l2cap_close(chan, ECONNRESET);
}
/*
* Process Received Disconnect Response. We must validate scid and dcid but
* unless we were waiting for this signal, ignore it.
*/
static void
l2cap_recv_disconnect_rsp(struct mbuf *m, struct hci_link *link)
{
l2cap_cmd_hdr_t cmd;
l2cap_discon_rsp_cp cp;
struct l2cap_req *req;
struct l2cap_channel *chan;
m_copydata(m, 0, sizeof(cmd), &cmd);
m_adj(m, sizeof(cmd));
m_copydata(m, 0, sizeof(cp), &cp);
m_adj(m, sizeof(cp));
cp.scid = le16toh(cp.scid);
cp.dcid = le16toh(cp.dcid);
req = l2cap_request_lookup(link, cmd.ident);
if (req == NULL || req->lr_code != L2CAP_DISCONNECT_REQ)
return;
chan = req->lr_chan;
if (chan == NULL
|| chan->lc_lcid != cp.scid
|| chan->lc_rcid != cp.dcid)
return;
l2cap_request_free(req);
if (chan->lc_state != L2CAP_WAIT_DISCONNECT)
return;
l2cap_close(chan, 0);
}
/*
* Process Received Info Request. We must respond but alas dont
* support anything as yet so thats easy.
*/
static void
l2cap_recv_info_req(struct mbuf *m, struct hci_link *link)
{
l2cap_cmd_hdr_t cmd;
l2cap_info_req_cp cp;
l2cap_info_rsp_cp rp;
m_copydata(m, 0, sizeof(cmd), &cmd);
m_adj(m, sizeof(cmd));
m_copydata(m, 0, sizeof(cp), &cp);
m_adj(m, sizeof(cp));
switch(le16toh(cp.type)) {
case L2CAP_CONNLESS_MTU:
case L2CAP_EXTENDED_FEATURES:
default:
rp.type = cp.type;
rp.result = htole16(L2CAP_NOT_SUPPORTED);
l2cap_send_signal(link, L2CAP_INFO_RSP, cmd.ident,
sizeof(rp), &rp);
break;
}
}
/*
* Construct signal and wrap in C-Frame for link.
*/
static int
l2cap_send_signal(struct hci_link *link, uint8_t code, uint8_t ident,
uint16_t length, void *data)
{
struct mbuf *m;
l2cap_hdr_t *hdr;
l2cap_cmd_hdr_t *cmd;
#ifdef DIAGNOSTIC
if (link == NULL)
return ENETDOWN;
if (sizeof(l2cap_cmd_hdr_t) + length > link->hl_mtu)
aprint_error_dev(link->hl_unit->hci_dev,
"exceeding L2CAP Signal MTU for link!\n");
#endif
m = m_gethdr(M_DONTWAIT, MT_DATA);
if (m == NULL)
return ENOMEM;
hdr = mtod(m, l2cap_hdr_t *);
cmd = (l2cap_cmd_hdr_t *)(hdr + 1);
m->m_len = m->m_pkthdr.len = MHLEN;
/* Command Data */
if (length > 0)
m_copyback(m, sizeof(*hdr) + sizeof(*cmd), length, data);
/* Command Header */
cmd->code = code;
cmd->ident = ident;
cmd->length = htole16(length);
length += sizeof(*cmd);
/* C-Frame Header */
hdr->length = htole16(length);
hdr->dcid = htole16(L2CAP_SIGNAL_CID);
length += sizeof(*hdr);
if (m->m_pkthdr.len != MAX(MHLEN, length)) {
m_freem(m);
return ENOMEM;
}
m->m_pkthdr.len = length;
m->m_len = MIN(length, MHLEN);
DPRINTFN(2, "(%s) code %d, ident %d, len %d\n",
device_xname(link->hl_unit->hci_dev), code, ident, length);
return hci_acl_send(m, link, NULL);
}
/*
* Send Command Reject packet.
*/
static int
l2cap_send_command_rej(struct hci_link *link, uint8_t ident,
uint16_t reason, ...)
{
l2cap_cmd_rej_cp cp;
int len = 0;
va_list ap;
va_start(ap, reason);
cp.reason = htole16(reason);
switch (reason) {
case L2CAP_REJ_NOT_UNDERSTOOD:
len = 2;
break;
case L2CAP_REJ_MTU_EXCEEDED:
len = 4;
cp.data[0] = va_arg(ap, int); /* SigMTU */
cp.data[0] = htole16(cp.data[0]);
break;
case L2CAP_REJ_INVALID_CID:
len = 6;
cp.data[0] = va_arg(ap, int); /* dcid */
cp.data[0] = htole16(cp.data[0]);
cp.data[1] = va_arg(ap, int); /* scid */
cp.data[1] = htole16(cp.data[1]);
break;
default:
UNKNOWN(reason);
return EINVAL;
}
va_end(ap);
return l2cap_send_signal(link, L2CAP_COMMAND_REJ, ident, len, &cp);
}
/*
* Send Connect Request
*/
int
l2cap_send_connect_req(struct l2cap_channel *chan)
{
l2cap_con_req_cp cp;
int err;
err = l2cap_request_alloc(chan, L2CAP_CONNECT_REQ);
if (err)
return err;
cp.psm = htole16(chan->lc_raddr.bt_psm);
cp.scid = htole16(chan->lc_lcid);
return l2cap_send_signal(chan->lc_link, L2CAP_CONNECT_REQ,
chan->lc_link->hl_lastid, sizeof(cp), &cp);
}
/*
* Send Config Request
*
* For outgoing config request, we only put options in the packet if they
* differ from the default and would have to be actioned. We dont support
* enough option types to make overflowing SigMTU an issue so it can all
* go in one packet.
*/
int
l2cap_send_config_req(struct l2cap_channel *chan)
{
l2cap_cfg_req_cp *cp;
l2cap_cfg_opt_t *opt;
l2cap_cfg_opt_val_t *val;
uint8_t *next, buf[L2CAP_MTU_MINIMUM];
int err;
err = l2cap_request_alloc(chan, L2CAP_CONFIG_REQ);
if (err)
return err;
/* Config Header (4 octets) */
cp = (l2cap_cfg_req_cp *)buf;
cp->dcid = htole16(chan->lc_rcid);
cp->flags = 0; /* "No Continuation" */
next = buf + sizeof(l2cap_cfg_req_cp);
/* Incoming MTU (4 octets) */
if (chan->lc_imtu != L2CAP_MTU_DEFAULT) {
opt = (l2cap_cfg_opt_t *)next;
opt->type = L2CAP_OPT_MTU;
opt->length = L2CAP_OPT_MTU_SIZE;
val = (l2cap_cfg_opt_val_t *)(opt + 1);
val->mtu = htole16(chan->lc_imtu);
next += sizeof(l2cap_cfg_opt_t) + L2CAP_OPT_MTU_SIZE;
}
/* Flush Timeout (4 octets) */
if (chan->lc_flush != L2CAP_FLUSH_TIMO_DEFAULT) {
opt = (l2cap_cfg_opt_t *)next;
opt->type = L2CAP_OPT_FLUSH_TIMO;
opt->length = L2CAP_OPT_FLUSH_TIMO_SIZE;
val = (l2cap_cfg_opt_val_t *)(opt + 1);
val->flush_timo = htole16(chan->lc_flush);
next += sizeof(l2cap_cfg_opt_t) + L2CAP_OPT_FLUSH_TIMO_SIZE;
}
/* Outgoing QoS Flow (24 octets) */
/* Retransmission & Flow Control (11 octets) */
/*
* From here we need to start paying attention to SigMTU as we have
* possibly overflowed the minimum supported..
*/
return l2cap_send_signal(chan->lc_link, L2CAP_CONFIG_REQ,
chan->lc_link->hl_lastid, (int)(next - buf), buf);
}
/*
* Send Disconnect Request
*/
int
l2cap_send_disconnect_req(struct l2cap_channel *chan)
{
l2cap_discon_req_cp cp;
int err;
err = l2cap_request_alloc(chan, L2CAP_DISCONNECT_REQ);
if (err)
return err;
cp.dcid = htole16(chan->lc_rcid);
cp.scid = htole16(chan->lc_lcid);
return l2cap_send_signal(chan->lc_link, L2CAP_DISCONNECT_REQ,
chan->lc_link->hl_lastid, sizeof(cp), &cp);
}
/*
* Send Connect Response
*/
int
l2cap_send_connect_rsp(struct hci_link *link, uint8_t ident, uint16_t dcid, uint16_t scid, uint16_t result)
{
l2cap_con_rsp_cp cp;
memset(&cp, 0, sizeof(cp));
cp.dcid = htole16(dcid);
cp.scid = htole16(scid);
cp.result = htole16(result);
return l2cap_send_signal(link, L2CAP_CONNECT_RSP, ident, sizeof(cp), &cp);
}
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