/*
* Ultra Wide Band
* Information Element Handling
*
* Copyright (C) 2005-2006 Intel Corporation
* Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
* Reinette Chatre <reinette.chatre@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
*/
#include "uwb-internal.h"
#define D_LOCAL 0
#include <linux/uwb/debug.h>
/**
* uwb_ie_next - get the next IE in a buffer
* @ptr: start of the buffer containing the IE data
* @len: length of the buffer
*
* Both @ptr and @len are updated so subsequent calls to uwb_ie_next()
* will get the next IE.
*
* NULL is returned (and @ptr and @len will not be updated) if there
* are no more IEs in the buffer or the buffer is too short.
*/
struct uwb_ie_hdr *uwb_ie_next(void **ptr, size_t *len)
{
struct uwb_ie_hdr *hdr;
size_t ie_len;
if (*len < sizeof(struct uwb_ie_hdr))
return NULL;
hdr = *ptr;
ie_len = sizeof(struct uwb_ie_hdr) + hdr->length;
if (*len < ie_len)
return NULL;
*ptr += ie_len;
*len -= ie_len;
return hdr;
}
EXPORT_SYMBOL_GPL(uwb_ie_next);
/**
* Get the IEs that a radio controller is sending in its beacon
*
* @uwb_rc: UWB Radio Controller
* @returns: Size read from the system
*
* We don't need to lock the uwb_rc's mutex because we don't modify
* anything. Once done with the iedata buffer, call
* uwb_rc_ie_release(iedata). Don't call kfree on it.
*/
ssize_t uwb_rc_get_ie(struct uwb_rc *uwb_rc, struct uwb_rc_evt_get_ie **pget_ie)
{
ssize_t result;
struct device *dev = &uwb_rc->uwb_dev.dev;
struct uwb_rccb *cmd = NULL;
struct uwb_rceb *reply = NULL;
struct uwb_rc_evt_get_ie *get_ie;
d_fnstart(3, dev, "(%p, %p)\n", uwb_rc, pget_ie);
result = -ENOMEM;
cmd = kzalloc(sizeof(*cmd), GFP_KERNEL);
if (cmd == NULL)
goto error_kzalloc;
cmd->bCommandType = UWB_RC_CET_GENERAL;
cmd->wCommand = cpu_to_le16(UWB_RC_CMD_GET_IE);
result = uwb_rc_vcmd(uwb_rc, "GET_IE", cmd, sizeof(*cmd),
UWB_RC_CET_GENERAL, UWB_RC_CMD_GET_IE,
&reply);
if (result < 0)
goto error_cmd;
get_ie = container_of(reply, struct uwb_rc_evt_get_ie, rceb);
if (result < sizeof(*get_ie)) {
dev_err(dev, "not enough data returned for decoding GET IE "
"(%zu bytes received vs %zu needed)\n",
result, sizeof(*get_ie));
result = -EINVAL;
} else if (result < sizeof(*get_ie) + le16_to_cpu(get_ie->wIELength)) {
dev_err(dev, "not enough data returned for decoding GET IE "
"payload (%zu bytes received vs %zu needed)\n", result,
sizeof(*get_ie) + le16_to_cpu(get_ie->wIELength));
result = -EINVAL;
} else
*pget_ie = get_ie;
error_cmd:
kfree(cmd);
error_kzalloc:
d_fnend(3, dev, "(%p, %p) = %d\n", uwb_rc, pget_ie, (int)result);
return result;
}
EXPORT_SYMBOL_GPL(uwb_rc_get_ie);
/*
* Given a pointer to an IE, print it in ASCII/hex followed by a new line
*
* @ie_hdr: pointer to the IE header. Length is in there, and it is
* guaranteed that the ie_hdr->length bytes following it are
* safely accesible.
*
* @_data: context data passed from uwb_ie_for_each(), an struct output_ctx
*/
int uwb_ie_dump_hex(struct uwb_dev *uwb_dev, const struct uwb_ie_hdr *ie_hdr,
size_t offset, void *_ctx)
{
struct uwb_buf_ctx *ctx = _ctx;
const u8 *pl = (void *)(ie_hdr + 1);
u8 pl_itr;
ctx->bytes += scnprintf(ctx->buf + ctx->bytes, ctx->size - ctx->bytes,
"%02x %02x ", (unsigned) ie_hdr->element_id,
(unsigned) ie_hdr->length);
pl_itr = 0;
while (pl_itr < ie_hdr->length && ctx->bytes < ctx->size)
ctx->bytes += scnprintf(ctx->buf + ctx->bytes,
ctx->size - ctx->bytes,
"%02x ", (unsigned) pl[pl_itr++]);
if (ctx->bytes < ctx->size)
ctx->buf[ctx->bytes++] = '\n';
return 0;
}
EXPORT_SYMBOL_GPL(uwb_ie_dump_hex);
/**
* Verify that a pointer in a buffer points to valid IE
*
* @start: pointer to start of buffer in which IE appears
* @itr: pointer to IE inside buffer that will be verified
* @top: pointer to end of buffer
*
* @returns: 0 if IE is valid, <0 otherwise
*
* Verification involves checking that the buffer can contain a
* header and the amount of data reported in the IE header can be found in
* the buffer.
*/
static
int uwb_rc_ie_verify(struct uwb_dev *uwb_dev, const void *start,
const void *itr, const void *top)
{
struct device *dev = &uwb_dev->dev;
const struct uwb_ie_hdr *ie_hdr;
if (top - itr < sizeof(*ie_hdr)) {
dev_err(dev, "Bad IE: no data to decode header "
"(%zu bytes left vs %zu needed) at offset %zu\n",
top - itr, sizeof(*ie_hdr), itr - start);
return -EINVAL;
}
ie_hdr = itr;
itr += sizeof(*ie_hdr);
if (top - itr < ie_hdr->length) {
dev_err(dev, "Bad IE: not enough data for payload "
"(%zu bytes left vs %zu needed) at offset %zu\n",
top - itr, (size_t)ie_hdr->length,
(void *)ie_hdr - start);
return -EINVAL;
}
return 0;
}
/**
* Walk a buffer filled with consecutive IE's a buffer
*
* @uwb_dev: UWB device this IEs belong to (for err messages mainly)
*
* @fn: function to call with each IE; if it returns 0, we keep
* traversing the buffer. If it returns !0, we'll stop and return
* that value.
*
* @data: pointer passed to @fn
*
* @buf: buffer where the consecutive IEs are located
*
* @size: size of @buf
*
* Each IE is checked for basic correctness (there is space left for
* the header and the payload). If that test is failed, we stop
* processing. For every good IE, @fn is called.
*/
ssize_t uwb_ie_for_each(struct uwb_dev *uwb_dev, uwb_ie_f fn, void *data,
const void *buf, size_t size)
{
ssize_t result = 0;
const struct uwb_ie_hdr *ie_hdr;
const void *itr = buf, *top = itr + size;
while (itr < top) {
if (uwb_rc_ie_verify(uwb_dev, buf, itr, top) != 0)
break;
ie_hdr = itr;
itr += sizeof(*ie_hdr) + ie_hdr->length;
result = fn(uwb_dev, ie_hdr, itr - buf, data);
if (result != 0)
break;
}
return result;
}
EXPORT_SYMBOL_GPL(uwb_ie_for_each);
/**
* Replace all IEs currently being transmitted by a device
*
* @cmd: pointer to the SET-IE command with the IEs to set
* @size: size of @buf
*/
int uwb_rc_set_ie(struct uwb_rc *rc, struct uwb_rc_cmd_set_ie *cmd)
{
int result;
struct device *dev = &rc->uwb_dev.dev;
struct uwb_rc_evt_set_ie reply;
reply.rceb.bEventType = UWB_RC_CET_GENERAL;
reply.rceb.wEvent = UWB_RC_CMD_SET_IE;
result = uwb_rc_cmd(rc, "SET-IE", &cmd->rccb,
sizeof(*cmd) + le16_to_cpu(cmd->wIELength),
&reply.rceb, sizeof(reply));
if (result < 0)
goto error_cmd;
else if (result != sizeof(reply)) {
dev_err(dev, "SET-IE: not enough data to decode reply "
"(%d bytes received vs %zu needed)\n",
result, sizeof(reply));
result = -EIO;
} else if (reply.bResultCode != UWB_RC_RES_SUCCESS) {
dev_err(dev, "SET-IE: command execution failed: %s (%d)\n",
uwb_rc_strerror(reply.bResultCode), reply.bResultCode);
result = -EIO;
} else
result = 0;
error_cmd:
return result;
}
/**
* Determine by IE id if IE is host settable
* WUSB 1.0 [8.6.2.8 Table 8.85]
*
* EXCEPTION:
* All but UWB_IE_WLP appears in Table 8.85 from WUSB 1.0. Setting this IE
* is required for the WLP substack to perform association with its WSS so
* we hope that the WUSB spec will be changed to reflect this.
*/
static
int uwb_rc_ie_is_host_settable(enum uwb_ie element_id)
{
if (element_id == UWB_PCA_AVAILABILITY ||
element_id == UWB_BP_SWITCH_IE ||
element_id == UWB_MAC_CAPABILITIES_IE ||
element_id == UWB_PHY_CAPABILITIES_IE ||
element_id == UWB_APP_SPEC_PROBE_IE ||
element_id == UWB_IDENTIFICATION_IE ||
element_id == UWB_MASTER_KEY_ID_IE ||
element_id == UWB_IE_WLP ||
element_id == UWB_APP_SPEC_IE)
return 1;
return 0;
}
/**
* Extract Host Settable IEs from IE
*
* @ie_data: pointer to buffer containing all IEs
* @size: size of buffer
*
* @returns: length of buffer that only includes host settable IEs
*
* Given a buffer of IEs we move all Host Settable IEs to front of buffer
* by overwriting the IEs that are not Host Settable.
* Buffer length is adjusted accordingly.
*/
static
ssize_t uwb_rc_parse_host_settable_ie(struct uwb_dev *uwb_dev,
void *ie_data, size_t size)
{
size_t new_len = size;
struct uwb_ie_hdr *ie_hdr;
size_t ie_length;
void *itr = ie_data, *top = itr + size;
while (itr < top) {
if (uwb_rc_ie_verify(uwb_dev, ie_data, itr, top) != 0)
break;
ie_hdr = itr;
ie_length = sizeof(*ie_hdr) + ie_hdr->length;
if (uwb_rc_ie_is_host_settable(ie_hdr->element_id)) {
itr += ie_length;
} else {
memmove(itr, itr + ie_length, top - (itr + ie_length));
new_len -= ie_length;
top -= ie_length;
}
}
return new_len;
}
/* Cleanup the whole IE management subsystem */
void uwb_rc_ie_init(struct uwb_rc *uwb_rc)
{
mutex_init(&uwb_rc->ies_mutex);
}
/**
* Set up cache for host settable IEs currently being transmitted
*
* First we just call GET-IE to get the current IEs being transmitted
* (or we workaround and pretend we did) and (because the format is
* the same) reuse that as the IE cache (with the command prefix, as
* explained in 'struct uwb_rc').
*
* @returns: size of cache created
*/
ssize_t uwb_rc_ie_setup(struct uwb_rc *uwb_rc)
{
struct device *dev = &uwb_rc->uwb_dev.dev;
ssize_t result;
size_t capacity;
struct uwb_rc_evt_get_ie *ie_info;
d_fnstart(3, dev, "(%p)\n", uwb_rc);
mutex_lock(&uwb_rc->ies_mutex);
result = uwb_rc_get_ie(uwb_rc, &ie_info);
if (result < 0)
goto error_get_ie;
capacity = result;
d_printf(5, dev, "Got IEs %zu bytes (%zu long at %p)\n", result,
(size_t)le16_to_cpu(ie_info->wIELength), ie_info);
/* Remove IEs that host should not set. */
result = uwb_rc_parse_host_settable_ie(&uwb_rc->uwb_dev,
ie_info->IEData, le16_to_cpu(ie_info->wIELength));
if (result < 0)
goto error_parse;
d_printf(5, dev, "purged non-settable IEs to %zu bytes\n", result);
uwb_rc->ies = (void *) ie_info;
uwb_rc->ies->rccb.bCommandType = UWB_RC_CET_GENERAL;
uwb_rc->ies->rccb.wCommand = cpu_to_le16(UWB_RC_CMD_SET_IE);
uwb_rc->ies_capacity = capacity;
d_printf(5, dev, "IE cache at %p %zu bytes, %zu capacity\n",
ie_info, result, capacity);
result = 0;
error_parse:
error_get_ie:
mutex_unlock(&uwb_rc->ies_mutex);
d_fnend(3, dev, "(%p) = %zu\n", uwb_rc, result);
return result;
}
/* Cleanup the whole IE management subsystem */
void uwb_rc_ie_release(struct uwb_rc *uwb_rc)
{
kfree(uwb_rc->ies);
uwb_rc->ies = NULL;
uwb_rc->ies_capacity = 0;
}
static
int __acc_size(struct uwb_dev *uwb_dev, const struct uwb_ie_hdr *ie_hdr,
size_t offset, void *_ctx)
{
size_t *acc_size = _ctx;
*acc_size += sizeof(*ie_hdr) + ie_hdr->length;
d_printf(6, &uwb_dev->dev, "new acc size %zu\n", *acc_size);
return 0;
}
/**
* Add a new IE to IEs currently being transmitted by device
*
* @ies: the buffer containing the new IE or IEs to be added to
* the device's beacon. The buffer will be verified for
* consistence (meaning the headers should be right) and
* consistent with the buffer size.
* @size: size of @ies (in bytes, total buffer size)
* @returns: 0 if ok, <0 errno code on error
*
* According to WHCI 0.95 [4.13.6] the driver will only receive the RCEB
* after the device sent the first beacon that includes the IEs specified
* in the SET IE command. We thus cannot send this command if the device is
* not beaconing. Instead, a SET IE command will be sent later right after
* we start beaconing.
*
* Setting an IE on the device will overwrite all current IEs in device. So
* we take the current IEs being transmitted by the device, append the
* new one, and call SET IE with all the IEs needed.
*
* The local IE cache will only be updated with the new IE if SET IE
* completed successfully.
*/
int uwb_rc_ie_add(struct uwb_rc *uwb_rc,
const struct uwb_ie_hdr *ies, size_t size)
{
int result = 0;
struct device *dev = &uwb_rc->uwb_dev.dev;
struct uwb_rc_cmd_set_ie *new_ies;
size_t ies_size, total_size, acc_size = 0;
if (uwb_rc->ies == NULL)
return -ESHUTDOWN;
uwb_ie_for_each(&uwb_rc->uwb_dev, __acc_size, &acc_size, ies, size);
if (acc_size != size) {
dev_err(dev, "BUG: bad IEs, misconstructed headers "
"[%zu bytes reported vs %zu calculated]\n",
size, acc_size);
WARN_ON(1);
return -EINVAL;
}
mutex_lock(&uwb_rc->ies_mutex);
ies_size = le16_to_cpu(uwb_rc->ies->wIELength);
total_size = sizeof(*uwb_rc->ies) + ies_size;
if (total_size + size > uwb_rc->ies_capacity) {
d_printf(4, dev, "Reallocating IE cache from %p capacity %zu "
"to capacity %zu\n", uwb_rc->ies, uwb_rc->ies_capacity,
total_size + size);
new_ies = kzalloc(total_size + size, GFP_KERNEL);
if (new_ies == NULL) {
dev_err(dev, "No memory for adding new IE\n");
result = -ENOMEM;
goto error_alloc;
}
memcpy(new_ies, uwb_rc->ies, total_size);
uwb_rc->ies_capacity = total_size + size;
kfree(uwb_rc->ies);
uwb_rc->ies = new_ies;
d_printf(4, dev, "New IE cache at %p capacity %zu\n",
uwb_rc->ies, uwb_rc->ies_capacity);
}
memcpy((void *)uwb_rc->ies + total_size, ies, size);
uwb_rc->ies->wIELength = cpu_to_le16(ies_size + size);
if (uwb_rc->beaconing != -1) {
result = uwb_rc_set_ie(uwb_rc, uwb_rc->ies);
if (result < 0) {
dev_err(dev, "Cannot set new IE on device: %d\n",
result);
uwb_rc->ies->wIELength = cpu_to_le16(ies_size);
} else
result = 0;
}
d_printf(4, dev, "IEs now occupy %hu bytes of %zu capacity at %p\n",
le16_to_cpu(uwb_rc->ies->wIELength), uwb_rc->ies_capacity,
uwb_rc->ies);
error_alloc:
mutex_unlock(&uwb_rc->ies_mutex);
return result;
}
EXPORT_SYMBOL_GPL(uwb_rc_ie_add);
/*
* Remove an IE from internal cache
*
* We are dealing with our internal IE cache so no need to verify that the
* IEs are valid (it has been done already).
*
* Should be called with ies_mutex held
*
* We do not break out once an IE is found in the cache. It is currently
* possible to have more than one IE with the same ID included in the
* beacon. We don't reallocate, we just mark the size smaller.
*/
static
int uwb_rc_ie_cache_rm(struct uwb_rc *uwb_rc, enum uwb_ie to_remove)
{
struct uwb_ie_hdr *ie_hdr;
size_t new_len = le16_to_cpu(uwb_rc->ies->wIELength);
void *itr = uwb_rc->ies->IEData;
void *top = itr + new_len;
while (itr < top) {
ie_hdr = itr;
if (ie_hdr->element_id != to_remove) {
itr += sizeof(*ie_hdr) + ie_hdr->length;
} else {
int ie_length;
ie_length = sizeof(*ie_hdr) + ie_hdr->length;
if (top - itr != ie_length)
memmove(itr, itr + ie_length, top - itr + ie_length);
top -= ie_length;
new_len -= ie_length;
}
}
uwb_rc->ies->wIELength = cpu_to_le16(new_len);
return 0;
}
/**
* Remove an IE currently being transmitted by device
*
* @element_id: id of IE to be removed from device's beacon
*/
int uwb_rc_ie_rm(struct uwb_rc *uwb_rc, enum uwb_ie element_id)
{
struct device *dev = &uwb_rc->uwb_dev.dev;
int result;
if (uwb_rc->ies == NULL)
return -ESHUTDOWN;
mutex_lock(&uwb_rc->ies_mutex);
result = uwb_rc_ie_cache_rm(uwb_rc, element_id);
if (result < 0)
dev_err(dev, "Cannot remove IE from cache.\n");
if (uwb_rc->beaconing != -1) {
result = uwb_rc_set_ie(uwb_rc, uwb_rc->ies);
if (result < 0)
dev_err(dev, "Cannot set new IE on device.\n");
}
mutex_unlock(&uwb_rc->ies_mutex);
return result;
}
EXPORT_SYMBOL_GPL(uwb_rc_ie_rm);
