/*
* WUSB Wire Adapter: Control/Data Streaming Interface (WUSB[8])
* Device Connect handling
*
* Copyright (C) 2006 Intel Corporation
* Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA.
*
*
* FIXME: docs
* FIXME: this file needs to be broken up, it's grown too big
*
*
* WUSB1.0[7.1, 7.5.1, ]
*
* WUSB device connection is kind of messy. Some background:
*
* When a device wants to connect it scans the UWB radio channels
* looking for a WUSB Channel; a WUSB channel is defined by MMCs
* (Micro Managed Commands or something like that) [see
* Design-overview for more on this] .
*
* So, device scans the radio, finds MMCs and thus a host and checks
* when the next DNTS is. It sends a Device Notification Connect
* (DN_Connect); the host picks it up (through nep.c and notif.c, ends
* up in wusb_devconnect_ack(), which creates a wusb_dev structure in
* wusbhc->port[port_number].wusb_dev), assigns an unauth address
* to the device (this means from 0x80 to 0xfe) and sends, in the MMC
* a Connect Ack Information Element (ConnAck IE).
*
* So now the device now has a WUSB address. From now on, we use
* that to talk to it in the RPipes.
*
* ASSUMPTIONS:
*
* - We use the the as device address the port number where it is
* connected (port 0 doesn't exist). For unauth, it is 128 + that.
*
* ROADMAP:
*
* This file contains the logic for doing that--entry points:
*
* wusb_devconnect_ack() Ack a device until _acked() called.
* Called by notif.c:wusb_handle_dn_connect()
* when a DN_Connect is received.
*
* wusb_devconnect_acked() Ack done, release resources.
*
* wusb_handle_dn_alive() Called by notif.c:wusb_handle_dn()
* for processing a DN_Alive pong from a device.
*
* wusb_handle_dn_disconnect()Called by notif.c:wusb_handle_dn() to
* process a disconenct request from a
* device.
*
* __wusb_dev_disable() Called by rh.c:wusbhc_rh_clear_port_feat() when
* disabling a port.
*
* wusb_devconnect_create() Called when creating the host by
* lc.c:wusbhc_create().
*
* wusb_devconnect_destroy() Cleanup called removing the host. Called
* by lc.c:wusbhc_destroy().
*
* Each Wireless USB host maintains a list of DN_Connect requests
* (actually we maintain a list of pending Connect Acks, the
* wusbhc->ca_list).
*
* LIFE CYCLE OF port->wusb_dev
*
* Before the @wusbhc structure put()s the reference it owns for
* port->wusb_dev [and clean the wusb_dev pointer], it needs to
* lock @wusbhc->mutex.
*/
#include <linux/jiffies.h>
#include <linux/ctype.h>
#include <linux/workqueue.h>
#include "wusbhc.h"
static void wusbhc_devconnect_acked_work(struct work_struct *work);
static void wusb_dev_free(struct wusb_dev *wusb_dev)
{
if (wusb_dev) {
kfree(wusb_dev->set_gtk_req);
usb_free_urb(wusb_dev->set_gtk_urb);
kfree(wusb_dev);
}
}
static struct wusb_dev *wusb_dev_alloc(struct wusbhc *wusbhc)
{
struct wusb_dev *wusb_dev;
struct urb *urb;
struct usb_ctrlrequest *req;
wusb_dev = kzalloc(sizeof(*wusb_dev), GFP_KERNEL);
if (wusb_dev == NULL)
goto err;
wusb_dev->wusbhc = wusbhc;
INIT_WORK(&wusb_dev->devconnect_acked_work, wusbhc_devconnect_acked_work);
urb = usb_alloc_urb(0, GFP_KERNEL);
if (urb == NULL)
goto err;
req = kmalloc(sizeof(struct usb_ctrlrequest), GFP_KERNEL);
if (req == NULL)
goto err;
req->bRequestType = USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE;
req->bRequest = USB_REQ_SET_DESCRIPTOR;
req->wValue = cpu_to_le16(USB_DT_KEY << 8 | wusbhc->gtk_index);
req->wIndex = 0;
req->wLength = cpu_to_le16(wusbhc->gtk.descr.bLength);
wusb_dev->set_gtk_urb = urb;
wusb_dev->set_gtk_req = req;
return wusb_dev;
err:
wusb_dev_free(wusb_dev);
return NULL;
}
/*
* Using the Connect-Ack list, fill out the @wusbhc Connect-Ack WUSB IE
* properly so that it can be added to the MMC.
*
* We just get the @wusbhc->ca_list and fill out the first four ones or
* less (per-spec WUSB1.0[7.5, before T7-38). If the ConnectAck WUSB
* IE is not allocated, we alloc it.
*
* @wusbhc->mutex must be taken
*/
static void wusbhc_fill_cack_ie(struct wusbhc *wusbhc)
{
unsigned cnt;
struct wusb_dev *dev_itr;
struct wuie_connect_ack *cack_ie;
cack_ie = &wusbhc->cack_ie;
cnt = 0;
list_for_each_entry(dev_itr, &wusbhc->cack_list, cack_node) {
cack_ie->blk[cnt].CDID = dev_itr->cdid;
cack_ie->blk[cnt].bDeviceAddress = dev_itr->addr;
if (++cnt >= WUIE_ELT_MAX)
break;
}
cack_ie->hdr.bLength = sizeof(cack_ie->hdr)
+ cnt * sizeof(cack_ie->blk[0]);
}
/*
* Register a new device that wants to connect
*
* A new device wants to connect, so we add it to the Connect-Ack
* list. We give it an address in the unauthorized range (bit 8 set);
* user space will have to drive authorization further on.
*
* @dev_addr: address to use for the device (which is also the port
* number).
*
* @wusbhc->mutex must be taken
*/
static struct wusb_dev *wusbhc_cack_add(struct wusbhc *wusbhc,
struct wusb_dn_connect *dnc,
const char *pr_cdid, u8 port_idx)
{
struct device *dev = wusbhc->dev;
struct wusb_dev *wusb_dev;
int new_connection = wusb_dn_connect_new_connection(dnc);
u8 dev_addr;
int result;
/* Is it registered already? */
list_for_each_entry(wusb_dev, &wusbhc->cack_list, cack_node)
if (!memcmp(&wusb_dev->cdid, &dnc->CDID,
sizeof(wusb_dev->cdid)))
return wusb_dev;
/* We don't have it, create an entry, register it */
wusb_dev = wusb_dev_alloc(wusbhc);
if (wusb_dev == NULL)
return NULL;
wusb_dev_init(wusb_dev);
wusb_dev->cdid = dnc->CDID;
wusb_dev->port_idx = port_idx;
/*
* Devices are always available within the cluster reservation
* and since the hardware will take the intersection of the
* per-device availability and the cluster reservation, the
* per-device availability can simply be set to always
* available.
*/
bitmap_fill(wusb_dev->availability.bm, UWB_NUM_MAS);
/* FIXME: handle reconnects instead of assuming connects are
always new. */
if (1 && new_connection == 0)
new_connection = 1;
if (new_connection) {
dev_addr = (port_idx + 2) | WUSB_DEV_ADDR_UNAUTH;
dev_info(dev, "Connecting new WUSB device to address %u, "
"port %u\n", dev_addr, port_idx);
result = wusb_set_dev_addr(wusbhc, wusb_dev, dev_addr);
if (result < 0)
return NULL;
}
wusb_dev->entry_ts = jiffies;
list_add_tail(&wusb_dev->cack_node, &wusbhc->cack_list);
wusbhc->cack_count++;
wusbhc_fill_cack_ie(wusbhc);
return wusb_dev;
}
/*
* Remove a Connect-Ack context entry from the HCs view
*
* @wusbhc->mutex must be taken
*/
static void wusbhc_cack_rm(struct wusbhc *wusbhc, struct wusb_dev *wusb_dev)
{
list_del_init(&wusb_dev->cack_node);
wusbhc->cack_count--;
wusbhc_fill_cack_ie(wusbhc);
}
/*
* @wusbhc->mutex must be taken */
static
void wusbhc_devconnect_acked(struct wusbhc *wusbhc, struct wusb_dev *wusb_dev)
{
wusbhc_cack_rm(wusbhc, wusb_dev);
if (wusbhc->cack_count)
wusbhc_mmcie_set(wusbhc, 0, 0, &wusbhc->cack_ie.hdr);
else
wusbhc_mmcie_rm(wusbhc, &wusbhc->cack_ie.hdr);
}
static void wusbhc_devconnect_acked_work(struct work_struct *work)
{
struct wusb_dev *wusb_dev = container_of(work, struct wusb_dev,
devconnect_acked_work);
struct wusbhc *wusbhc = wusb_dev->wusbhc;
mutex_lock(&wusbhc->mutex);
wusbhc_devconnect_acked(wusbhc, wusb_dev);
mutex_unlock(&wusbhc->mutex);
}
/*
* Ack a device for connection
*
* FIXME: docs
*
* @pr_cdid: Printable CDID...hex Use @dnc->cdid for the real deal.
*
* So we get the connect ack IE (may have been allocated already),
* find an empty connect block, an empty virtual port, create an
* address with it (see below), make it an unauth addr [bit 7 set] and
* set the MMC.
*
* Addresses: because WUSB hosts have no downstream hubs, we can do a
* 1:1 mapping between 'port number' and device
* address. This simplifies many things, as during this
* initial connect phase the USB stack has no knoledge of
* the device and hasn't assigned an address yet--we know
* USB's choose_address() will use the same euristics we
* use here, so we can assume which address will be assigned.
*
* USB stack always assigns address 1 to the root hub, so
* to the port number we add 2 (thus virtual port #0 is
* addr #2).
*
* @wusbhc shall be referenced
*/
static
void wusbhc_devconnect_ack(struct wusbhc *wusbhc, struct wusb_dn_connect *dnc,
const char *pr_cdid)
{
int result;
struct device *dev = wusbhc->dev;
struct wusb_dev *wusb_dev;
struct wusb_port *port;
unsigned idx, devnum;
mutex_lock(&wusbhc->mutex);
/* Check we are not handling it already */
for (idx = 0; idx < wusbhc->ports_max; idx++) {
port = wusb_port_by_idx(wusbhc, idx);
if (port->wusb_dev
&& memcmp(&dnc->CDID, &port->wusb_dev->cdid, sizeof(dnc->CDID)) == 0)
goto error_unlock;
}
/* Look up those fake ports we have for a free one */
for (idx = 0; idx < wusbhc->ports_max; idx++) {
port = wusb_port_by_idx(wusbhc, idx);
if ((port->status & USB_PORT_STAT_POWER)
&& !(port->status & USB_PORT_STAT_CONNECTION))
break;
}
if (idx >= wusbhc->ports_max) {
dev_err(dev, "Host controller can't connect more devices "
"(%u already connected); device %s rejected\n",
wusbhc->ports_max, pr_cdid);
/* NOTE: we could send a WUIE_Disconnect here, but we haven't
* event acked, so the device will eventually timeout the
* connection, right? */
goto error_unlock;
}
devnum = idx + 2;
/* Make sure we are using no crypto on that "virtual port" */
wusbhc->set_ptk(wusbhc, idx, 0, NULL, 0);
/* Grab a filled in Connect-Ack context, fill out the
* Connect-Ack Wireless USB IE, set the MMC */
wusb_dev = wusbhc_cack_add(wusbhc, dnc, pr_cdid, idx);
if (wusb_dev == NULL)
goto error_unlock;
result = wusbhc_mmcie_set(wusbhc, 0, 0, &wusbhc->cack_ie.hdr);
if (result < 0)
goto error_unlock;
/* Give the device at least 2ms (WUSB1.0[7.5.1p3]), let's do
* three for a good measure */
msleep(3);
port->wusb_dev = wusb_dev;
port->status |= USB_PORT_STAT_CONNECTION;
port->change |= USB_PORT_STAT_C_CONNECTION;
/* Now the port status changed to connected; khubd will
* pick the change up and try to reset the port to bring it to
* the enabled state--so this process returns up to the stack
* and it calls back into wusbhc_rh_port_reset().
*/
error_unlock:
mutex_unlock(&wusbhc->mutex);
return;
}
/*
* Disconnect a Wireless USB device from its fake port
*
* Marks the port as disconnected so that khubd can pick up the change
* and drops our knowledge about the device.
*
* Assumes there is a device connected
*
* @port_index: zero based port number
*
* NOTE: @wusbhc->mutex is locked
*
* WARNING: From here it is not very safe to access anything hanging off
* wusb_dev
*/
static void __wusbhc_dev_disconnect(struct wusbhc *wusbhc,
struct wusb_port *port)
{
struct wusb_dev *wusb_dev = port->wusb_dev;
port->status &= ~(USB_PORT_STAT_CONNECTION | USB_PORT_STAT_ENABLE
| USB_PORT_STAT_SUSPEND | USB_PORT_STAT_RESET
| USB_PORT_STAT_LOW_SPEED | USB_PORT_STAT_HIGH_SPEED);
port->change |= USB_PORT_STAT_C_CONNECTION | USB_PORT_STAT_C_ENABLE;
if (wusb_dev) {
dev_dbg(wusbhc->dev, "disconnecting device from port %d\n", wusb_dev->port_idx);
if (!list_empty(&wusb_dev->cack_node))
list_del_init(&wusb_dev->cack_node);
/* For the one in cack_add() */
wusb_dev_put(wusb_dev);
}
port->wusb_dev = NULL;
/* After a device disconnects, change the GTK (see [WUSB]
* section 6.2.11.2). */
wusbhc_gtk_rekey(wusbhc);
/* The Wireless USB part has forgotten about the device already; now
* khubd's timer will pick up the disconnection and remove the USB
* device from the system
*/
}
/*
* Refresh the list of keep alives to emit in the MMC
*
* Some devices don't respond to keep alives unless they've been
* authenticated, so skip unauthenticated devices.
*
* We only publish the first four devices that have a coming timeout
* condition. Then when we are done processing those, we go for the
* next ones. We ignore the ones that have timed out already (they'll
* be purged).
*
* This might cause the first devices to timeout the last devices in
* the port array...FIXME: come up with a better algorithm?
*
* Note we can't do much about MMC's ops errors; we hope next refresh
* will kind of handle it.
*
* NOTE: @wusbhc->mutex is locked
*/
static void __wusbhc_keep_alive(struct wusbhc *wusbhc)
{
struct device *dev = wusbhc->dev;
unsigned cnt;
struct wusb_dev *wusb_dev;
struct wusb_port *wusb_port;
struct wuie_keep_alive *ie = &wusbhc->keep_alive_ie;
unsigned keep_alives, old_keep_alives;
old_keep_alives = ie->hdr.bLength - sizeof(ie->hdr);
keep_alives = 0;
for (cnt = 0;
keep_alives <= WUIE_ELT_MAX && cnt < wusbhc->ports_max;
cnt++) {
unsigned tt = msecs_to_jiffies(wusbhc->trust_timeout);
wusb_port = wusb_port_by_idx(wusbhc, cnt);
wusb_dev = wusb_port->wusb_dev;
if (wusb_dev == NULL)
continue;
if (wusb_dev->usb_dev == NULL || !wusb_dev->usb_dev->authenticated)
continue;
if (time_after(jiffies, wusb_dev->entry_ts + tt)) {
dev_err(dev, "KEEPALIVE: device %u timed out\n",
wusb_dev->addr);
__wusbhc_dev_disconnect(wusbhc, wusb_port);
} else if (time_after(jiffies, wusb_dev->entry_ts + tt/2)) {
/* Approaching timeout cut out, need to refresh */
ie->bDeviceAddress[keep_alives++] = wusb_dev->addr;
}
}
if (keep_alives & 0x1) /* pad to even number ([WUSB] section 7.5.9) */
ie->bDeviceAddress[keep_alives++] = 0x7f;
ie->hdr.bLength = sizeof(ie->hdr) +
keep_alives*sizeof(ie->bDeviceAddress[0]);
if (keep_alives > 0)
wusbhc_mmcie_set(wusbhc, 10, 5, &ie->hdr);
else if (old_keep_alives != 0)
wusbhc_mmcie_rm(wusbhc, &ie->hdr);
}
/*
* Do a run through all devices checking for timeouts
*/
static void wusbhc_keep_alive_run(struct work_struct *ws)
{
struct delayed_work *dw = container_of(ws, struct delayed_work, work);
struct wusbhc *wusbhc = container_of(dw, struct wusbhc, keep_alive_timer);
mutex_lock(&wusbhc->mutex);
__wusbhc_keep_alive(wusbhc);
mutex_unlock(&wusbhc->mutex);
queue_delayed_work(wusbd, &wusbhc->keep_alive_timer,
msecs_to_jiffies(wusbhc->trust_timeout / 2));
}
/*
* Find the wusb_dev from its device address.
*
* The device can be found directly from the address (see
* wusb_cack_add() for where the device address is set to port_idx
* +2), except when the address is zero.
*/
static struct wusb_dev *wusbhc_find_dev_by_addr(struct wusbhc *wusbhc, u8 addr)
{
int p;
if (addr == 0xff) /* unconnected */
return NULL;
if (addr > 0) {
int port = (addr & ~0x80) - 2;
if (port < 0 || port >= wusbhc->ports_max)
return NULL;
return wusb_port_by_idx(wusbhc, port)->wusb_dev;
}
/* Look for the device with address 0. */
for (p = 0; p < wusbhc->ports_max; p++) {
struct wusb_dev *wusb_dev = wusb_port_by_idx(wusbhc, p)->wusb_dev;
if (wusb_dev && wusb_dev->addr == addr)
return wusb_dev;
}
return NULL;
}
/*
* Handle a DN_Alive notification (WUSB1.0[7.6.1])
*
* This just updates the device activity timestamp and then refreshes
* the keep alive IE.
*
* @wusbhc shall be referenced and unlocked
*/
static void wusbhc_handle_dn_alive(struct wusbhc *wusbhc, struct wusb_dev *wusb_dev)
{
mutex_lock(&wusbhc->mutex);
wusb_dev->entry_ts = jiffies;
__wusbhc_keep_alive(wusbhc);
mutex_unlock(&wusbhc->mutex);
}
/*
* Handle a DN_Connect notification (WUSB1.0[7.6.1])
*
* @wusbhc
* @pkt_hdr
* @size: Size of the buffer where the notification resides; if the
* notification data suggests there should be more data than
* available, an error will be signaled and the whole buffer
* consumed.
*
* @wusbhc->mutex shall be held
*/
static void wusbhc_handle_dn_connect(struct wusbhc *wusbhc,
struct wusb_dn_hdr *dn_hdr,
size_t size)
{
struct device *dev = wusbhc->dev;
struct wusb_dn_connect *dnc;
char pr_cdid[WUSB_CKHDID_STRSIZE];
static const char *beacon_behaviour[] = {
"reserved",
"self-beacon",
"directed-beacon",
"no-beacon"
};
if (size < sizeof(*dnc)) {
dev_err(dev, "DN CONNECT: short notification (%zu < %zu)\n",
size, sizeof(*dnc));
return;
}
dnc = container_of(dn_hdr, struct wusb_dn_connect, hdr);
ckhdid_printf(pr_cdid, sizeof(pr_cdid), &dnc->CDID);
dev_info(dev, "DN CONNECT: device %s @ %x (%s) wants to %s\n",
pr_cdid,
wusb_dn_connect_prev_dev_addr(dnc),
beacon_behaviour[wusb_dn_connect_beacon_behavior(dnc)],
wusb_dn_connect_new_connection(dnc) ? "connect" : "reconnect");
/* ACK the connect */
wusbhc_devconnect_ack(wusbhc, dnc, pr_cdid);
}
/*
* Handle a DN_Disconnect notification (WUSB1.0[7.6.1])
*
* Device is going down -- do the disconnect.
*
* @wusbhc shall be referenced and unlocked
*/
static void wusbhc_handle_dn_disconnect(struct wusbhc *wusbhc, struct wusb_dev *wusb_dev)
{
struct device *dev = wusbhc->dev;
dev_info(dev, "DN DISCONNECT: device 0x%02x going down\n", wusb_dev->addr);
mutex_lock(&wusbhc->mutex);
__wusbhc_dev_disconnect(wusbhc, wusb_port_by_idx(wusbhc, wusb_dev->port_idx));
mutex_unlock(&wusbhc->mutex);
}
/*
* Handle a Device Notification coming a host
*
* The Device Notification comes from a host (HWA, DWA or WHCI)
* wrapped in a set of headers. Somebody else has peeled off those
* headers for us and we just get one Device Notifications.
*
* Invalid DNs (e.g., too short) are discarded.
*
* @wusbhc shall be referenced
*
* FIXMES:
* - implement priorities as in WUSB1.0[Table 7-55]?
*/
void wusbhc_handle_dn(struct wusbhc *wusbhc, u8 srcaddr,
struct wusb_dn_hdr *dn_hdr, size_t size)
{
struct device *dev = wusbhc->dev;
struct wusb_dev *wusb_dev;
if (size < sizeof(struct wusb_dn_hdr)) {
dev_err(dev, "DN data shorter than DN header (%d < %d)\n",
(int)size, (int)sizeof(struct wusb_dn_hdr));
return;
}
wusb_dev = wusbhc_find_dev_by_addr(wusbhc, srcaddr);
if (wusb_dev == NULL && dn_hdr->bType != WUSB_DN_CONNECT) {
dev_dbg(dev, "ignoring DN %d from unconnected device %02x\n",
dn_hdr->bType, srcaddr);
return;
}
switch (dn_hdr->bType) {
case WUSB_DN_CONNECT:
wusbhc_handle_dn_connect(wusbhc, dn_hdr, size);
break;
case WUSB_DN_ALIVE:
wusbhc_handle_dn_alive(wusbhc, wusb_dev);
break;
case WUSB_DN_DISCONNECT:
wusbhc_handle_dn_disconnect(wusbhc, wusb_dev);
break;
case WUSB_DN_MASAVAILCHANGED:
case WUSB_DN_RWAKE:
case WUSB_DN_SLEEP:
/* FIXME: handle these DNs. */
break;
case WUSB_DN_EPRDY:
/* The hardware handles these. */
break;
default:
dev_warn(dev, "unknown DN %u (%d octets) from %u\n",
dn_hdr->bType, (int)size, srcaddr);
}
}
EXPORT_SYMBOL_GPL(wusbhc_handle_dn);
/*
* Disconnect a WUSB device from a the cluster
*
* @wusbhc
* @port Fake port where the device is (wusbhc index, not USB port number).
*
* In Wireless USB, a disconnect is basically telling the device he is
* being disconnected and forgetting about him.
*
* We send the device a Device Disconnect IE (WUSB1.0[7.5.11]) for 100
* ms and then keep going.
*
* We don't do much in case of error; we always pretend we disabled
* the port and disconnected the device. If physically the request
* didn't get there (many things can fail in the way there), the stack
* will reject the device's communication attempts.
*
* @wusbhc should be refcounted and locked
*/
void __wusbhc_dev_disable(struct wusbhc *wusbhc, u8 port_idx)
{
int result;
struct device *dev = wusbhc->dev;
struct wusb_dev *wusb_dev;
struct wuie_disconnect *ie;
wusb_dev = wusb_port_by_idx(wusbhc, port_idx)->wusb_dev;
if (wusb_dev == NULL) {
/* reset no device? ignore */
dev_dbg(dev, "DISCONNECT: no device at port %u, ignoring\n",
port_idx);
return;
}
__wusbhc_dev_disconnect(wusbhc, wusb_port_by_idx(wusbhc, port_idx));
ie = kzalloc(sizeof(*ie), GFP_KERNEL);
if (ie == NULL)
return;
ie->hdr.bLength = sizeof(*ie);
ie->hdr.bIEIdentifier = WUIE_ID_DEVICE_DISCONNECT;
ie->bDeviceAddress = wusb_dev->addr;
result = wusbhc_mmcie_set(wusbhc, 0, 0, &ie->hdr);
if (result < 0)
dev_err(dev, "DISCONNECT: can't set MMC: %d\n", result);
else {
/* At least 6 MMCs, assuming at least 1 MMC per zone. */
msleep(7*4);
wusbhc_mmcie_rm(wusbhc, &ie->hdr);
}
kfree(ie);
}
/*
* Walk over the BOS descriptor, verify and grok it
*
* @usb_dev: referenced
* @wusb_dev: referenced and unlocked
*
* The BOS descriptor is defined at WUSB1.0[7.4.1], and it defines a
* "flexible" way to wrap all kinds of descriptors inside an standard
* descriptor (wonder why they didn't use normal descriptors,
* btw). Not like they lack code.
*
* At the end we go to look for the WUSB Device Capabilities
* (WUSB1.0[7.4.1.1]) that is wrapped in a device capability descriptor
* that is part of the BOS descriptor set. That tells us what does the
* device support (dual role, beacon type, UWB PHY rates).
*/
static int wusb_dev_bos_grok(struct usb_device *usb_dev,
struct wusb_dev *wusb_dev,
struct usb_bos_descriptor *bos, size_t desc_size)
{
ssize_t result;
struct device *dev = &usb_dev->dev;
void *itr, *top;
/* Walk over BOS capabilities, verify them */
itr = (void *)bos + sizeof(*bos);
top = itr + desc_size - sizeof(*bos);
while (itr < top) {
struct usb_dev_cap_header *cap_hdr = itr;
size_t cap_size;
u8 cap_type;
if (top - itr < sizeof(*cap_hdr)) {
dev_err(dev, "Device BUG? premature end of BOS header "
"data [offset 0x%02x]: only %zu bytes left\n",
(int)(itr - (void *)bos), top - itr);
result = -ENOSPC;
goto error_bad_cap;
}
cap_size = cap_hdr->bLength;
cap_type = cap_hdr->bDevCapabilityType;
if (cap_size == 0)
break;
if (cap_size > top - itr) {
dev_err(dev, "Device BUG? premature end of BOS data "
"[offset 0x%02x cap %02x %zu bytes]: "
"only %zu bytes left\n",
(int)(itr - (void *)bos),
cap_type, cap_size, top - itr);
result = -EBADF;
goto error_bad_cap;
}
switch (cap_type) {
case USB_CAP_TYPE_WIRELESS_USB:
if (cap_size != sizeof(*wusb_dev->wusb_cap_descr))
dev_err(dev, "Device BUG? WUSB Capability "
"descriptor is %zu bytes vs %zu "
"needed\n", cap_size,
sizeof(*wusb_dev->wusb_cap_descr));
else
wusb_dev->wusb_cap_descr = itr;
break;
default:
dev_err(dev, "BUG? Unknown BOS capability 0x%02x "
"(%zu bytes) at offset 0x%02x\n", cap_type,
cap_size, (int)(itr - (void *)bos));
}
itr += cap_size;
}
result = 0;
error_bad_cap:
return result;
}
/*
* Add information from the BOS descriptors to the device
*
* @usb_dev: referenced
* @wusb_dev: referenced and unlocked
*
* So what we do is we alloc a space for the BOS descriptor of 64
* bytes; read the first four bytes which include the wTotalLength
* field (WUSB1.0[T7-26]) and if it fits in those 64 bytes, read the
* whole thing. If not we realloc to that size.
*
* Then we call the groking function, that will fill up
* wusb_dev->wusb_cap_descr, which is what we'll need later on.
*/
static int wusb_dev_bos_add(struct usb_device *usb_dev,
struct wusb_dev *wusb_dev)
{
ssize_t result;
struct device *dev = &usb_dev->dev;
struct usb_bos_descriptor *bos;
size_t alloc_size = 32, desc_size = 4;
bos = kmalloc(alloc_size, GFP_KERNEL);
if (bos == NULL)
return -ENOMEM;
result = usb_get_descriptor(usb_dev, USB_DT_BOS, 0, bos, desc_size);
if (result < 4) {
dev_err(dev, "Can't get BOS descriptor or too short: %zd\n",
result);
goto error_get_descriptor;
}
desc_size = le16_to_cpu(bos->wTotalLength);
if (desc_size >= alloc_size) {
kfree(bos);
alloc_size = desc_size;
bos = kmalloc(alloc_size, GFP_KERNEL);
if (bos == NULL)
return -ENOMEM;
}
result = usb_get_descriptor(usb_dev, USB_DT_BOS, 0, bos, desc_size);
if (result < 0 || result != desc_size) {
dev_err(dev, "Can't get BOS descriptor or too short (need "
"%zu bytes): %zd\n", desc_size, result);
goto error_get_descriptor;
}
if (result < sizeof(*bos)
|| le16_to_cpu(bos->wTotalLength) != desc_size) {
dev_err(dev, "Can't get BOS descriptor or too short (need "
"%zu bytes): %zd\n", desc_size, result);
goto error_get_descriptor;
}
result = wusb_dev_bos_grok(usb_dev, wusb_dev, bos, result);
if (result < 0)
goto error_bad_bos;
wusb_dev->bos = bos;
return 0;
error_bad_bos:
error_get_descriptor:
kfree(bos);
wusb_dev->wusb_cap_descr = NULL;
return result;
}
static void wusb_dev_bos_rm(struct wusb_dev *wusb_dev)
{
kfree(wusb_dev->bos);
wusb_dev->wusb_cap_descr = NULL;
};
static struct usb_wireless_cap_descriptor wusb_cap_descr_default = {
.bLength = sizeof(wusb_cap_descr_default),
.bDescriptorType = USB_DT_DEVICE_CAPABILITY,
.bDevCapabilityType = USB_CAP_TYPE_WIRELESS_USB,
.bmAttributes = USB_WIRELESS_BEACON_NONE,
.wPHYRates = cpu_to_le16(USB_WIRELESS_PHY_53),
.bmTFITXPowerInfo = 0,
.bmFFITXPowerInfo = 0,
.bmBandGroup = cpu_to_le16(0x0001), /* WUSB1.0[7.4.1] bottom */
.bReserved = 0
};
/*
* USB stack's device addition Notifier Callback
*
* Called from drivers/usb/core/hub.c when a new device is added; we
* use this hook to perform certain WUSB specific setup work on the
* new device. As well, it is the first time we can connect the
* wusb_dev and the usb_dev. So we note it down in wusb_dev and take a
* reference that we'll drop.
*
* First we need to determine if the device is a WUSB device (else we
* ignore it). For that we use the speed setting (USB_SPEED_VARIABLE)
* [FIXME: maybe we'd need something more definitive]. If so, we track
* it's usb_busd and from there, the WUSB HC.
*
* Because all WUSB HCs are contained in a 'struct wusbhc', voila, we
* get the wusbhc for the device.
*
* We have a reference on @usb_dev (as we are called at the end of its
* enumeration).
*
* NOTE: @usb_dev locked
*/
static void wusb_dev_add_ncb(struct usb_device *usb_dev)
{
int result = 0;
struct wusb_dev *wusb_dev;
struct wusbhc *wusbhc;
struct device *dev = &usb_dev->dev;
u8 port_idx;
if (usb_dev->wusb == 0 || usb_dev->devnum == 1)
return; /* skip non wusb and wusb RHs */
wusbhc = wusbhc_get_by_usb_dev(usb_dev);
if (wusbhc == NULL)
goto error_nodev;
mutex_lock(&wusbhc->mutex);
wusb_dev = __wusb_dev_get_by_usb_dev(wusbhc, usb_dev);
port_idx = wusb_port_no_to_idx(usb_dev->portnum);
mutex_unlock(&wusbhc->mutex);
if (wusb_dev == NULL)
goto error_nodev;
wusb_dev->usb_dev = usb_get_dev(usb_dev);
usb_dev->wusb_dev = wusb_dev_get(wusb_dev);
result = wusb_dev_sec_add(wusbhc, usb_dev, wusb_dev);
if (result < 0) {
dev_err(dev, "Cannot enable security: %d\n", result);
goto error_sec_add;
}
/* Now query the device for it's BOS and attach it to wusb_dev */
result = wusb_dev_bos_add(usb_dev, wusb_dev);
if (result < 0) {
dev_err(dev, "Cannot get BOS descriptors: %d\n", result);
goto error_bos_add;
}
result = wusb_dev_sysfs_add(wusbhc, usb_dev, wusb_dev);
if (result < 0)
goto error_add_sysfs;
out:
wusb_dev_put(wusb_dev);
wusbhc_put(wusbhc);
error_nodev:
return;
wusb_dev_sysfs_rm(wusb_dev);
error_add_sysfs:
wusb_dev_bos_rm(wusb_dev);
error_bos_add:
wusb_dev_sec_rm(wusb_dev);
error_sec_add:
mutex_lock(&wusbhc->mutex);
__wusbhc_dev_disconnect(wusbhc, wusb_port_by_idx(wusbhc, port_idx));
mutex_unlock(&wusbhc->mutex);
goto out;
}
/*
* Undo all the steps done at connection by the notifier callback
*
* NOTE: @usb_dev locked
*/
static void wusb_dev_rm_ncb(struct usb_device *usb_dev)
{
struct wusb_dev *wusb_dev = usb_dev->wusb_dev;
if (usb_dev->wusb == 0 || usb_dev->devnum == 1)
return; /* skip non wusb and wusb RHs */
wusb_dev_sysfs_rm(wusb_dev);
wusb_dev_bos_rm(wusb_dev);
wusb_dev_sec_rm(wusb_dev);
wusb_dev->usb_dev = NULL;
usb_dev->wusb_dev = NULL;
wusb_dev_put(wusb_dev);
usb_put_dev(usb_dev);
}
/*
* Handle notifications from the USB stack (notifier call back)
*
* This is called when the USB stack does a
* usb_{bus,device}_{add,remove}() so we can do WUSB specific
* handling. It is called with [for the case of
* USB_DEVICE_{ADD,REMOVE} with the usb_dev locked.
*/
int wusb_usb_ncb(struct notifier_block *nb, unsigned long val,
void *priv)
{
int result = NOTIFY_OK;
switch (val) {
case USB_DEVICE_ADD:
wusb_dev_add_ncb(priv);
break;
case USB_DEVICE_REMOVE:
wusb_dev_rm_ncb(priv);
break;
case USB_BUS_ADD:
/* ignore (for now) */
case USB_BUS_REMOVE:
break;
default:
WARN_ON(1);
result = NOTIFY_BAD;
};
return result;
}
/*
* Return a referenced wusb_dev given a @wusbhc and @usb_dev
*/
struct wusb_dev *__wusb_dev_get_by_usb_dev(struct wusbhc *wusbhc,
struct usb_device *usb_dev)
{
struct wusb_dev *wusb_dev;
u8 port_idx;
port_idx = wusb_port_no_to_idx(usb_dev->portnum);
BUG_ON(port_idx > wusbhc->ports_max);
wusb_dev = wusb_port_by_idx(wusbhc, port_idx)->wusb_dev;
if (wusb_dev != NULL) /* ops, device is gone */
wusb_dev_get(wusb_dev);
return wusb_dev;
}
EXPORT_SYMBOL_GPL(__wusb_dev_get_by_usb_dev);
void wusb_dev_destroy(struct kref *_wusb_dev)
{
struct wusb_dev *wusb_dev = container_of(_wusb_dev, struct wusb_dev, refcnt);
list_del_init(&wusb_dev->cack_node);
wusb_dev_free(wusb_dev);
}
EXPORT_SYMBOL_GPL(wusb_dev_destroy);
/*
* Create all the device connect handling infrastructure
*
* This is basically the device info array, Connect Acknowledgement
* (cack) lists, keep-alive timers (and delayed work thread).
*/
int wusbhc_devconnect_create(struct wusbhc *wusbhc)
{
wusbhc->keep_alive_ie.hdr.bIEIdentifier = WUIE_ID_KEEP_ALIVE;
wusbhc->keep_alive_ie.hdr.bLength = sizeof(wusbhc->keep_alive_ie.hdr);
INIT_DELAYED_WORK(&wusbhc->keep_alive_timer, wusbhc_keep_alive_run);
wusbhc->cack_ie.hdr.bIEIdentifier = WUIE_ID_CONNECTACK;
wusbhc->cack_ie.hdr.bLength = sizeof(wusbhc->cack_ie.hdr);
INIT_LIST_HEAD(&wusbhc->cack_list);
return 0;
}
/*
* Release all resources taken by the devconnect stuff
*/
void wusbhc_devconnect_destroy(struct wusbhc *wusbhc)
{
/* no op */
}
/*
* wusbhc_devconnect_start - start accepting device connections
* @wusbhc: the WUSB HC
*
* Sets the Host Info IE to accept all new connections.
*
* FIXME: This also enables the keep alives but this is not necessary
* until there are connected and authenticated devices.
*/
int wusbhc_devconnect_start(struct wusbhc *wusbhc)
{
struct device *dev = wusbhc->dev;
struct wuie_host_info *hi;
int result;
hi = kzalloc(sizeof(*hi), GFP_KERNEL);
if (hi == NULL)
return -ENOMEM;
hi->hdr.bLength = sizeof(*hi);
hi->hdr.bIEIdentifier = WUIE_ID_HOST_INFO;
hi->attributes = cpu_to_le16((wusbhc->rsv->stream << 3) | WUIE_HI_CAP_ALL);
hi->CHID = wusbhc->chid;
result = wusbhc_mmcie_set(wusbhc, 0, 0, &hi->hdr);
if (result < 0) {
dev_err(dev, "Cannot add Host Info MMCIE: %d\n", result);
goto error_mmcie_set;
}
wusbhc->wuie_host_info = hi;
queue_delayed_work(wusbd, &wusbhc->keep_alive_timer,
(wusbhc->trust_timeout*CONFIG_HZ)/1000/2);
return 0;
error_mmcie_set:
kfree(hi);
return result;
}
/*
* wusbhc_devconnect_stop - stop managing connected devices
* @wusbhc: the WUSB HC
*
* Removes the Host Info IE and stops the keep alives.
*
* FIXME: should this disconnect all devices?
*/
void wusbhc_devconnect_stop(struct wusbhc *wusbhc)
{
cancel_delayed_work_sync(&wusbhc->keep_alive_timer);
WARN_ON(!list_empty(&wusbhc->cack_list));
wusbhc_mmcie_rm(wusbhc, &wusbhc->wuie_host_info->hdr);
kfree(wusbhc->wuie_host_info);
wusbhc->wuie_host_info = NULL;
}
/*
* wusb_set_dev_addr - set the WUSB device address used by the host
* @wusbhc: the WUSB HC the device is connect to
* @wusb_dev: the WUSB device
* @addr: new device address
*/
int wusb_set_dev_addr(struct wusbhc *wusbhc, struct wusb_dev *wusb_dev, u8 addr)
{
int result;
wusb_dev->addr = addr;
result = wusbhc->dev_info_set(wusbhc, wusb_dev);
if (result < 0)
dev_err(wusbhc->dev, "device %d: failed to set device "
"address\n", wusb_dev->port_idx);
else
dev_info(wusbhc->dev, "device %d: %s addr %u\n",
wusb_dev->port_idx,
(addr & WUSB_DEV_ADDR_UNAUTH) ? "unauth" : "auth",
wusb_dev->addr);
return result;
}
