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linux/net/wireless/wext.c
Johannes Berg 1dacc76d00 net/compat/wext: send different messages to compat tasks 
Wireless extensions have the unfortunate problem that events
are multicast netlink messages, and are not independent of
pointer size. Thus, currently 32-bit tasks on 64-bit platforms
cannot properly receive events and fail with all kinds of
strange problems, for instance wpa_supplicant never notices
disassociations, due to the way the 64-bit event looks (to a
32-bit process), the fact that the address is all zeroes is
lost, it thinks instead it is 00:00:00:00:01:00.

The same problem existed with the ioctls, until David Miller
fixed those some time ago in an heroic effort.

A different problem caused by this is that we cannot send the
ASSOCREQIE/ASSOCRESPIE events because sending them causes a
32-bit wpa_supplicant on a 64-bit system to overwrite its
internal information, which is worse than it not getting the
information at all -- so we currently resort to sending a
custom string event that it then parses. This, however, has a
severe size limitation we are frequently hitting with modern
access points; this limitation would can be lifted after this
patch by sending the correct binary, not custom, event.

A similar problem apparently happens for some other netlink
users on x86_64 with 32-bit tasks due to the alignment for
64-bit quantities.

In order to fix these problems, I have implemented a way to
send compat messages to tasks. When sending an event, we send
the non-compat event data together with a compat event data in
skb_shinfo(main_skb)->frag_list. Then, when the event is read
from the socket, the netlink code makes sure to pass out only
the skb that is compatible with the task. This approach was
suggested by David Miller, my original approach required
always sending two skbs but that had various small problems.

To determine whether compat is needed or not, I have used the
MSG_CMSG_COMPAT flag, and adjusted the call path for recv and
recvfrom to include it, even if those calls do not have a cmsg
parameter.

I have not solved one small part of the problem, and I don't
think it is necessary to: if a 32-bit application uses read()
rather than any form of recvmsg() it will still get the wrong
(64-bit) event. However, neither do applications actually do
this, nor would it be a regression.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-07-15 08:53:39 -07:00

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/*
* This file implement the Wireless Extensions APIs.
*
* Authors : Jean Tourrilhes - HPL - <jt@hpl.hp.com>
* Copyright (c) 1997-2007 Jean Tourrilhes, All Rights Reserved.
*
* (As all part of the Linux kernel, this file is GPL)
*/
/************************** DOCUMENTATION **************************/
/*
* API definition :
* --------------
* See <linux/wireless.h> for details of the APIs and the rest.
*
* History :
* -------
*
* v1 - 5.12.01 - Jean II
* o Created this file.
*
* v2 - 13.12.01 - Jean II
* o Move /proc/net/wireless stuff from net/core/dev.c to here
* o Make Wireless Extension IOCTLs go through here
* o Added iw_handler handling ;-)
* o Added standard ioctl description
* o Initial dumb commit strategy based on orinoco.c
*
* v3 - 19.12.01 - Jean II
* o Make sure we don't go out of standard_ioctl[] in ioctl_standard_call
* o Add event dispatcher function
* o Add event description
* o Propagate events as rtnetlink IFLA_WIRELESS option
* o Generate event on selected SET requests
*
* v4 - 18.04.02 - Jean II
* o Fix stupid off by one in iw_ioctl_description : IW_ESSID_MAX_SIZE + 1
*
* v5 - 21.06.02 - Jean II
* o Add IW_PRIV_TYPE_ADDR in priv_type_size (+cleanup)
* o Reshuffle IW_HEADER_TYPE_XXX to map IW_PRIV_TYPE_XXX changes
* o Add IWEVCUSTOM for driver specific event/scanning token
* o Turn on WE_STRICT_WRITE by default + kernel warning
* o Fix WE_STRICT_WRITE in ioctl_export_private() (32 => iw_num)
* o Fix off-by-one in test (extra_size <= IFNAMSIZ)
*
* v6 - 9.01.03 - Jean II
* o Add common spy support : iw_handler_set_spy(), wireless_spy_update()
* o Add enhanced spy support : iw_handler_set_thrspy() and event.
* o Add WIRELESS_EXT version display in /proc/net/wireless
*
* v6 - 18.06.04 - Jean II
* o Change get_spydata() method for added safety
* o Remove spy #ifdef, they are always on -> cleaner code
* o Allow any size GET request if user specifies length > max
* and if request has IW_DESCR_FLAG_NOMAX flag or is SIOCGIWPRIV
* o Start migrating get_wireless_stats to struct iw_handler_def
* o Add wmb() in iw_handler_set_spy() for non-coherent archs/cpus
* Based on patch from Pavel Roskin <proski@gnu.org> :
* o Fix kernel data leak to user space in private handler handling
*
* v7 - 18.3.05 - Jean II
* o Remove (struct iw_point *)->pointer from events and streams
* o Remove spy_offset from struct iw_handler_def
* o Start deprecating dev->get_wireless_stats, output a warning
* o If IW_QUAL_DBM is set, show dBm values in /proc/net/wireless
* o Don't lose INVALID/DBM flags when clearing UPDATED flags (iwstats)
*
* v8 - 17.02.06 - Jean II
* o RtNetlink requests support (SET/GET)
*
* v8b - 03.08.06 - Herbert Xu
* o Fix Wireless Event locking issues.
*
* v9 - 14.3.06 - Jean II
* o Change length in ESSID and NICK to strlen() instead of strlen()+1
* o Make standard_ioctl_num and standard_event_num unsigned
* o Remove (struct net_device *)->get_wireless_stats()
*
* v10 - 16.3.07 - Jean II
* o Prevent leaking of kernel space in stream on 64 bits.
*/
/***************************** INCLUDES *****************************/
#include <linux/module.h>
#include <linux/types.h> /* off_t */
#include <linux/netdevice.h> /* struct ifreq, dev_get_by_name() */
#include <linux/proc_fs.h>
#include <linux/rtnetlink.h> /* rtnetlink stuff */
#include <linux/seq_file.h>
#include <linux/init.h> /* for __init */
#include <linux/if_arp.h> /* ARPHRD_ETHER */
#include <linux/etherdevice.h> /* compare_ether_addr */
#include <linux/interrupt.h>
#include <net/net_namespace.h>
#include <linux/wireless.h> /* Pretty obvious */
#include <net/iw_handler.h> /* New driver API */
#include <net/netlink.h>
#include <net/wext.h>
#include <asm/uaccess.h> /* copy_to_user() */
/************************* GLOBAL VARIABLES *************************/
/*
* You should not use global variables, because of re-entrancy.
* On our case, it's only const, so it's OK...
*/
/*
* Meta-data about all the standard Wireless Extension request we
* know about.
*/
static const struct iw_ioctl_description standard_ioctl[] = {
[SIOCSIWCOMMIT - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_NULL,
},
[SIOCGIWNAME - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_CHAR,
.flags = IW_DESCR_FLAG_DUMP,
},
[SIOCSIWNWID - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_PARAM,
.flags = IW_DESCR_FLAG_EVENT,
},
[SIOCGIWNWID - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_PARAM,
.flags = IW_DESCR_FLAG_DUMP,
},
[SIOCSIWFREQ - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_FREQ,
.flags = IW_DESCR_FLAG_EVENT,
},
[SIOCGIWFREQ - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_FREQ,
.flags = IW_DESCR_FLAG_DUMP,
},
[SIOCSIWMODE - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_UINT,
.flags = IW_DESCR_FLAG_EVENT,
},
[SIOCGIWMODE - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_UINT,
.flags = IW_DESCR_FLAG_DUMP,
},
[SIOCSIWSENS - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_PARAM,
},
[SIOCGIWSENS - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_PARAM,
},
[SIOCSIWRANGE - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_NULL,
},
[SIOCGIWRANGE - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_POINT,
.token_size = 1,
.max_tokens = sizeof(struct iw_range),
.flags = IW_DESCR_FLAG_DUMP,
},
[SIOCSIWPRIV - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_NULL,
},
[SIOCGIWPRIV - SIOCIWFIRST] = { /* (handled directly by us) */
.header_type = IW_HEADER_TYPE_POINT,
.token_size = sizeof(struct iw_priv_args),
.max_tokens = 16,
.flags = IW_DESCR_FLAG_NOMAX,
},
[SIOCSIWSTATS - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_NULL,
},
[SIOCGIWSTATS - SIOCIWFIRST] = { /* (handled directly by us) */
.header_type = IW_HEADER_TYPE_POINT,
.token_size = 1,
.max_tokens = sizeof(struct iw_statistics),
.flags = IW_DESCR_FLAG_DUMP,
},
[SIOCSIWSPY - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_POINT,
.token_size = sizeof(struct sockaddr),
.max_tokens = IW_MAX_SPY,
},
[SIOCGIWSPY - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_POINT,
.token_size = sizeof(struct sockaddr) +
sizeof(struct iw_quality),
.max_tokens = IW_MAX_SPY,
},
[SIOCSIWTHRSPY - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_POINT,
.token_size = sizeof(struct iw_thrspy),
.min_tokens = 1,
.max_tokens = 1,
},
[SIOCGIWTHRSPY - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_POINT,
.token_size = sizeof(struct iw_thrspy),
.min_tokens = 1,
.max_tokens = 1,
},
[SIOCSIWAP - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_ADDR,
},
[SIOCGIWAP - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_ADDR,
.flags = IW_DESCR_FLAG_DUMP,
},
[SIOCSIWMLME - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_POINT,
.token_size = 1,
.min_tokens = sizeof(struct iw_mlme),
.max_tokens = sizeof(struct iw_mlme),
},
[SIOCGIWAPLIST - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_POINT,
.token_size = sizeof(struct sockaddr) +
sizeof(struct iw_quality),
.max_tokens = IW_MAX_AP,
.flags = IW_DESCR_FLAG_NOMAX,
},
[SIOCSIWSCAN - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_POINT,
.token_size = 1,
.min_tokens = 0,
.max_tokens = sizeof(struct iw_scan_req),
},
[SIOCGIWSCAN - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_POINT,
.token_size = 1,
.max_tokens = IW_SCAN_MAX_DATA,
.flags = IW_DESCR_FLAG_NOMAX,
},
[SIOCSIWESSID - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_POINT,
.token_size = 1,
.max_tokens = IW_ESSID_MAX_SIZE,
.flags = IW_DESCR_FLAG_EVENT,
},
[SIOCGIWESSID - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_POINT,
.token_size = 1,
.max_tokens = IW_ESSID_MAX_SIZE,
.flags = IW_DESCR_FLAG_DUMP,
},
[SIOCSIWNICKN - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_POINT,
.token_size = 1,
.max_tokens = IW_ESSID_MAX_SIZE,
},
[SIOCGIWNICKN - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_POINT,
.token_size = 1,
.max_tokens = IW_ESSID_MAX_SIZE,
},
[SIOCSIWRATE - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_PARAM,
},
[SIOCGIWRATE - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_PARAM,
},
[SIOCSIWRTS - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_PARAM,
},
[SIOCGIWRTS - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_PARAM,
},
[SIOCSIWFRAG - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_PARAM,
},
[SIOCGIWFRAG - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_PARAM,
},
[SIOCSIWTXPOW - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_PARAM,
},
[SIOCGIWTXPOW - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_PARAM,
},
[SIOCSIWRETRY - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_PARAM,
},
[SIOCGIWRETRY - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_PARAM,
},
[SIOCSIWENCODE - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_POINT,
.token_size = 1,
.max_tokens = IW_ENCODING_TOKEN_MAX,
.flags = IW_DESCR_FLAG_EVENT | IW_DESCR_FLAG_RESTRICT,
},
[SIOCGIWENCODE - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_POINT,
.token_size = 1,
.max_tokens = IW_ENCODING_TOKEN_MAX,
.flags = IW_DESCR_FLAG_DUMP | IW_DESCR_FLAG_RESTRICT,
},
[SIOCSIWPOWER - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_PARAM,
},
[SIOCGIWPOWER - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_PARAM,
},
[SIOCSIWGENIE - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_POINT,
.token_size = 1,
.max_tokens = IW_GENERIC_IE_MAX,
},
[SIOCGIWGENIE - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_POINT,
.token_size = 1,
.max_tokens = IW_GENERIC_IE_MAX,
},
[SIOCSIWAUTH - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_PARAM,
},
[SIOCGIWAUTH - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_PARAM,
},
[SIOCSIWENCODEEXT - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_POINT,
.token_size = 1,
.min_tokens = sizeof(struct iw_encode_ext),
.max_tokens = sizeof(struct iw_encode_ext) +
IW_ENCODING_TOKEN_MAX,
},
[SIOCGIWENCODEEXT - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_POINT,
.token_size = 1,
.min_tokens = sizeof(struct iw_encode_ext),
.max_tokens = sizeof(struct iw_encode_ext) +
IW_ENCODING_TOKEN_MAX,
},
[SIOCSIWPMKSA - SIOCIWFIRST] = {
.header_type = IW_HEADER_TYPE_POINT,
.token_size = 1,
.min_tokens = sizeof(struct iw_pmksa),
.max_tokens = sizeof(struct iw_pmksa),
},
};
static const unsigned standard_ioctl_num = ARRAY_SIZE(standard_ioctl);
/*
* Meta-data about all the additional standard Wireless Extension events
* we know about.
*/
static const struct iw_ioctl_description standard_event[] = {
[IWEVTXDROP - IWEVFIRST] = {
.header_type = IW_HEADER_TYPE_ADDR,
},
[IWEVQUAL - IWEVFIRST] = {
.header_type = IW_HEADER_TYPE_QUAL,
},
[IWEVCUSTOM - IWEVFIRST] = {
.header_type = IW_HEADER_TYPE_POINT,
.token_size = 1,
.max_tokens = IW_CUSTOM_MAX,
},
[IWEVREGISTERED - IWEVFIRST] = {
.header_type = IW_HEADER_TYPE_ADDR,
},
[IWEVEXPIRED - IWEVFIRST] = {
.header_type = IW_HEADER_TYPE_ADDR,
},
[IWEVGENIE - IWEVFIRST] = {
.header_type = IW_HEADER_TYPE_POINT,
.token_size = 1,
.max_tokens = IW_GENERIC_IE_MAX,
},
[IWEVMICHAELMICFAILURE - IWEVFIRST] = {
.header_type = IW_HEADER_TYPE_POINT,
.token_size = 1,
.max_tokens = sizeof(struct iw_michaelmicfailure),
},
[IWEVASSOCREQIE - IWEVFIRST] = {
.header_type = IW_HEADER_TYPE_POINT,
.token_size = 1,
.max_tokens = IW_GENERIC_IE_MAX,
},
[IWEVASSOCRESPIE - IWEVFIRST] = {
.header_type = IW_HEADER_TYPE_POINT,
.token_size = 1,
.max_tokens = IW_GENERIC_IE_MAX,
},
[IWEVPMKIDCAND - IWEVFIRST] = {
.header_type = IW_HEADER_TYPE_POINT,
.token_size = 1,
.max_tokens = sizeof(struct iw_pmkid_cand),
},
};
static const unsigned standard_event_num = ARRAY_SIZE(standard_event);
/* Size (in bytes) of the various private data types */
static const char iw_priv_type_size[] = {
0, /* IW_PRIV_TYPE_NONE */
1, /* IW_PRIV_TYPE_BYTE */
1, /* IW_PRIV_TYPE_CHAR */
0, /* Not defined */
sizeof(__u32), /* IW_PRIV_TYPE_INT */
sizeof(struct iw_freq), /* IW_PRIV_TYPE_FLOAT */
sizeof(struct sockaddr), /* IW_PRIV_TYPE_ADDR */
0, /* Not defined */
};
/* Size (in bytes) of various events */
static const int event_type_size[] = {
IW_EV_LCP_LEN, /* IW_HEADER_TYPE_NULL */
0,
IW_EV_CHAR_LEN, /* IW_HEADER_TYPE_CHAR */
0,
IW_EV_UINT_LEN, /* IW_HEADER_TYPE_UINT */
IW_EV_FREQ_LEN, /* IW_HEADER_TYPE_FREQ */
IW_EV_ADDR_LEN, /* IW_HEADER_TYPE_ADDR */
0,
IW_EV_POINT_LEN, /* Without variable payload */
IW_EV_PARAM_LEN, /* IW_HEADER_TYPE_PARAM */
IW_EV_QUAL_LEN, /* IW_HEADER_TYPE_QUAL */
};
#ifdef CONFIG_COMPAT
static const int compat_event_type_size[] = {
IW_EV_COMPAT_LCP_LEN, /* IW_HEADER_TYPE_NULL */
0,
IW_EV_COMPAT_CHAR_LEN, /* IW_HEADER_TYPE_CHAR */
0,
IW_EV_COMPAT_UINT_LEN, /* IW_HEADER_TYPE_UINT */
IW_EV_COMPAT_FREQ_LEN, /* IW_HEADER_TYPE_FREQ */
IW_EV_COMPAT_ADDR_LEN, /* IW_HEADER_TYPE_ADDR */
0,
IW_EV_COMPAT_POINT_LEN, /* Without variable payload */
IW_EV_COMPAT_PARAM_LEN, /* IW_HEADER_TYPE_PARAM */
IW_EV_COMPAT_QUAL_LEN, /* IW_HEADER_TYPE_QUAL */
};
#endif
/************************ COMMON SUBROUTINES ************************/
/*
* Stuff that may be used in various place or doesn't fit in one
* of the section below.
*/
/* ---------------------------------------------------------------- */
/*
* Return the driver handler associated with a specific Wireless Extension.
*/
static iw_handler get_handler(struct net_device *dev, unsigned int cmd)
{
/* Don't "optimise" the following variable, it will crash */
unsigned int index; /* *MUST* be unsigned */
/* Check if we have some wireless handlers defined */
if (dev->wireless_handlers == NULL)
return NULL;
/* Try as a standard command */
index = cmd - SIOCIWFIRST;
if (index < dev->wireless_handlers->num_standard)
return dev->wireless_handlers->standard[index];
/* Try as a private command */
index = cmd - SIOCIWFIRSTPRIV;
if (index < dev->wireless_handlers->num_private)
return dev->wireless_handlers->private[index];
/* Not found */
return NULL;
}
/* ---------------------------------------------------------------- */
/*
* Get statistics out of the driver
*/
static struct iw_statistics *get_wireless_stats(struct net_device *dev)
{
/* New location */
if ((dev->wireless_handlers != NULL) &&
(dev->wireless_handlers->get_wireless_stats != NULL))
return dev->wireless_handlers->get_wireless_stats(dev);
/* Not found */
return NULL;
}
/* ---------------------------------------------------------------- */
/*
* Call the commit handler in the driver
* (if exist and if conditions are right)
*
* Note : our current commit strategy is currently pretty dumb,
* but we will be able to improve on that...
* The goal is to try to agreagate as many changes as possible
* before doing the commit. Drivers that will define a commit handler
* are usually those that need a reset after changing parameters, so
* we want to minimise the number of reset.
* A cool idea is to use a timer : at each "set" command, we re-set the
* timer, when the timer eventually fires, we call the driver.
* Hopefully, more on that later.
*
* Also, I'm waiting to see how many people will complain about the
* netif_running(dev) test. I'm open on that one...
* Hopefully, the driver will remember to do a commit in "open()" ;-)
*/
static int call_commit_handler(struct net_device *dev)
{
if ((netif_running(dev)) &&
(dev->wireless_handlers->standard[0] != NULL))
/* Call the commit handler on the driver */
return dev->wireless_handlers->standard[0](dev, NULL,
NULL, NULL);
else
return 0; /* Command completed successfully */
}
/* ---------------------------------------------------------------- */
/*
* Calculate size of private arguments
*/
static int get_priv_size(__u16 args)
{
int num = args & IW_PRIV_SIZE_MASK;
int type = (args & IW_PRIV_TYPE_MASK) >> 12;
return num * iw_priv_type_size[type];
}
/* ---------------------------------------------------------------- */
/*
* Re-calculate the size of private arguments
*/
static int adjust_priv_size(__u16 args, struct iw_point *iwp)
{
int num = iwp->length;
int max = args & IW_PRIV_SIZE_MASK;
int type = (args & IW_PRIV_TYPE_MASK) >> 12;
/* Make sure the driver doesn't goof up */
if (max < num)
num = max;
return num * iw_priv_type_size[type];
}
/* ---------------------------------------------------------------- */
/*
* Standard Wireless Handler : get wireless stats
* Allow programatic access to /proc/net/wireless even if /proc
* doesn't exist... Also more efficient...
*/
static int iw_handler_get_iwstats(struct net_device * dev,
struct iw_request_info * info,
union iwreq_data * wrqu,
char * extra)
{
/* Get stats from the driver */
struct iw_statistics *stats;
stats = get_wireless_stats(dev);
if (stats) {
/* Copy statistics to extra */
memcpy(extra, stats, sizeof(struct iw_statistics));
wrqu->data.length = sizeof(struct iw_statistics);
/* Check if we need to clear the updated flag */
if (wrqu->data.flags != 0)
stats->qual.updated &= ~IW_QUAL_ALL_UPDATED;
return 0;
} else
return -EOPNOTSUPP;
}
/* ---------------------------------------------------------------- */
/*
* Standard Wireless Handler : get iwpriv definitions
* Export the driver private handler definition
* They will be picked up by tools like iwpriv...
*/
static int iw_handler_get_private(struct net_device * dev,
struct iw_request_info * info,
union iwreq_data * wrqu,
char * extra)
{
/* Check if the driver has something to export */
if ((dev->wireless_handlers->num_private_args == 0) ||
(dev->wireless_handlers->private_args == NULL))
return -EOPNOTSUPP;
/* Check if there is enough buffer up there */
if (wrqu->data.length < dev->wireless_handlers->num_private_args) {
/* User space can't know in advance how large the buffer
* needs to be. Give it a hint, so that we can support
* any size buffer we want somewhat efficiently... */
wrqu->data.length = dev->wireless_handlers->num_private_args;
return -E2BIG;
}
/* Set the number of available ioctls. */
wrqu->data.length = dev->wireless_handlers->num_private_args;
/* Copy structure to the user buffer. */
memcpy(extra, dev->wireless_handlers->private_args,
sizeof(struct iw_priv_args) * wrqu->data.length);
return 0;
}
/******************** /proc/net/wireless SUPPORT ********************/
/*
* The /proc/net/wireless file is a human readable user-space interface
* exporting various wireless specific statistics from the wireless devices.
* This is the most popular part of the Wireless Extensions ;-)
*
* This interface is a pure clone of /proc/net/dev (in net/core/dev.c).
* The content of the file is basically the content of "struct iw_statistics".
*/
#ifdef CONFIG_PROC_FS
/* ---------------------------------------------------------------- */
/*
* Print one entry (line) of /proc/net/wireless
*/
static void wireless_seq_printf_stats(struct seq_file *seq,
struct net_device *dev)
{
/* Get stats from the driver */
struct iw_statistics *stats = get_wireless_stats(dev);
static struct iw_statistics nullstats = {};
/* show device if it's wireless regardless of current stats */
if (!stats && dev->wireless_handlers)
stats = &nullstats;
if (stats) {
seq_printf(seq, "%6s: %04x %3d%c %3d%c %3d%c %6d %6d %6d "
"%6d %6d %6d\n",
dev->name, stats->status, stats->qual.qual,
stats->qual.updated & IW_QUAL_QUAL_UPDATED
? '.' : ' ',
((__s32) stats->qual.level) -
((stats->qual.updated & IW_QUAL_DBM) ? 0x100 : 0),
stats->qual.updated & IW_QUAL_LEVEL_UPDATED
? '.' : ' ',
((__s32) stats->qual.noise) -
((stats->qual.updated & IW_QUAL_DBM) ? 0x100 : 0),
stats->qual.updated & IW_QUAL_NOISE_UPDATED
? '.' : ' ',
stats->discard.nwid, stats->discard.code,
stats->discard.fragment, stats->discard.retries,
stats->discard.misc, stats->miss.beacon);
if (stats != &nullstats)
stats->qual.updated &= ~IW_QUAL_ALL_UPDATED;
}
}
/* ---------------------------------------------------------------- */
/*
* Print info for /proc/net/wireless (print all entries)
*/
static int wireless_dev_seq_show(struct seq_file *seq, void *v)
{
might_sleep();
if (v == SEQ_START_TOKEN)
seq_printf(seq, "Inter-| sta-| Quality | Discarded "
"packets | Missed | WE\n"
" face | tus | link level noise | nwid "
"crypt frag retry misc | beacon | %d\n",
WIRELESS_EXT);
else
wireless_seq_printf_stats(seq, v);
return 0;
}
static void *wireless_dev_seq_start(struct seq_file *seq, loff_t *pos)
{
struct net *net = seq_file_net(seq);
loff_t off;
struct net_device *dev;
rtnl_lock();
if (!*pos)
return SEQ_START_TOKEN;
off = 1;
for_each_netdev(net, dev)
if (off++ == *pos)
return dev;
return NULL;
}
static void *wireless_dev_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
struct net *net = seq_file_net(seq);
++*pos;
return v == SEQ_START_TOKEN ?
first_net_device(net) : next_net_device(v);
}
static void wireless_dev_seq_stop(struct seq_file *seq, void *v)
{
rtnl_unlock();
}
static const struct seq_operations wireless_seq_ops = {
.start = wireless_dev_seq_start,
.next = wireless_dev_seq_next,
.stop = wireless_dev_seq_stop,
.show = wireless_dev_seq_show,
};
static int seq_open_wireless(struct inode *inode, struct file *file)
{
return seq_open_net(inode, file, &wireless_seq_ops,
sizeof(struct seq_net_private));
}
static const struct file_operations wireless_seq_fops = {
.owner = THIS_MODULE,
.open = seq_open_wireless,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release_net,
};
int wext_proc_init(struct net *net)
{
/* Create /proc/net/wireless entry */
if (!proc_net_fops_create(net, "wireless", S_IRUGO, &wireless_seq_fops))
return -ENOMEM;
return 0;
}
void wext_proc_exit(struct net *net)
{
proc_net_remove(net, "wireless");
}
#endif /* CONFIG_PROC_FS */
/************************** IOCTL SUPPORT **************************/
/*
* The original user space API to configure all those Wireless Extensions
* is through IOCTLs.
* In there, we check if we need to call the new driver API (iw_handler)
* or just call the driver ioctl handler.
*/
/* ---------------------------------------------------------------- */
static int ioctl_standard_iw_point(struct iw_point *iwp, unsigned int cmd,
const struct iw_ioctl_description *descr,
iw_handler handler, struct net_device *dev,
struct iw_request_info *info)
{
int err, extra_size, user_length = 0, essid_compat = 0;
char *extra;
/* Calculate space needed by arguments. Always allocate
* for max space.
*/
extra_size = descr->max_tokens * descr->token_size;
/* Check need for ESSID compatibility for WE < 21 */
switch (cmd) {
case SIOCSIWESSID:
case SIOCGIWESSID:
case SIOCSIWNICKN:
case SIOCGIWNICKN:
if (iwp->length == descr->max_tokens + 1)
essid_compat = 1;
else if (IW_IS_SET(cmd) && (iwp->length != 0)) {
char essid[IW_ESSID_MAX_SIZE + 1];
err = copy_from_user(essid, iwp->pointer,
iwp->length *
descr->token_size);
if (err)
return -EFAULT;
if (essid[iwp->length - 1] == '\0')
essid_compat = 1;
}
break;
default:
break;
}
iwp->length -= essid_compat;
/* Check what user space is giving us */
if (IW_IS_SET(cmd)) {
/* Check NULL pointer */
if (!iwp->pointer && iwp->length != 0)
return -EFAULT;
/* Check if number of token fits within bounds */
if (iwp->length > descr->max_tokens)
return -E2BIG;
if (iwp->length < descr->min_tokens)
return -EINVAL;
} else {
/* Check NULL pointer */
if (!iwp->pointer)
return -EFAULT;
/* Save user space buffer size for checking */
user_length = iwp->length;
/* Don't check if user_length > max to allow forward
* compatibility. The test user_length < min is
* implied by the test at the end.
*/
/* Support for very large requests */
if ((descr->flags & IW_DESCR_FLAG_NOMAX) &&
(user_length > descr->max_tokens)) {
/* Allow userspace to GET more than max so
* we can support any size GET requests.
* There is still a limit : -ENOMEM.
*/
extra_size = user_length * descr->token_size;
/* Note : user_length is originally a __u16,
* and token_size is controlled by us,
* so extra_size won't get negative and
* won't overflow...
*/
}
}
/* kzalloc() ensures NULL-termination for essid_compat. */
extra = kzalloc(extra_size, GFP_KERNEL);
if (!extra)
return -ENOMEM;
/* If it is a SET, get all the extra data in here */
if (IW_IS_SET(cmd) && (iwp->length != 0)) {
if (copy_from_user(extra, iwp->pointer,
iwp->length *
descr->token_size)) {
err = -EFAULT;
goto out;
}
if (cmd == SIOCSIWENCODEEXT) {
struct iw_encode_ext *ee = (void *) extra;
if (iwp->length < sizeof(*ee) + ee->key_len)
return -EFAULT;
}
}
err = handler(dev, info, (union iwreq_data *) iwp, extra);
iwp->length += essid_compat;
/* If we have something to return to the user */
if (!err && IW_IS_GET(cmd)) {
/* Check if there is enough buffer up there */
if (user_length < iwp->length) {
err = -E2BIG;
goto out;
}
if (copy_to_user(iwp->pointer, extra,
iwp->length *
descr->token_size)) {
err = -EFAULT;
goto out;
}
}
/* Generate an event to notify listeners of the change */
if ((descr->flags & IW_DESCR_FLAG_EVENT) && err == -EIWCOMMIT) {
union iwreq_data *data = (union iwreq_data *) iwp;
if (descr->flags & IW_DESCR_FLAG_RESTRICT)
/* If the event is restricted, don't
* export the payload.
*/
wireless_send_event(dev, cmd, data, NULL);
else
wireless_send_event(dev, cmd, data, extra);
}
out:
kfree(extra);
return err;
}
/*
* Wrapper to call a standard Wireless Extension handler.
* We do various checks and also take care of moving data between
* user space and kernel space.
*/
static int ioctl_standard_call(struct net_device * dev,
struct iwreq *iwr,
unsigned int cmd,
struct iw_request_info *info,
iw_handler handler)
{
const struct iw_ioctl_description * descr;
int ret = -EINVAL;
/* Get the description of the IOCTL */
if ((cmd - SIOCIWFIRST) >= standard_ioctl_num)
return -EOPNOTSUPP;
descr = &(standard_ioctl[cmd - SIOCIWFIRST]);
/* Check if we have a pointer to user space data or not */
if (descr->header_type != IW_HEADER_TYPE_POINT) {
/* No extra arguments. Trivial to handle */
ret = handler(dev, info, &(iwr->u), NULL);
/* Generate an event to notify listeners of the change */
if ((descr->flags & IW_DESCR_FLAG_EVENT) &&
((ret == 0) || (ret == -EIWCOMMIT)))
wireless_send_event(dev, cmd, &(iwr->u), NULL);
} else {
ret = ioctl_standard_iw_point(&iwr->u.data, cmd, descr,
handler, dev, info);
}
/* Call commit handler if needed and defined */
if (ret == -EIWCOMMIT)
ret = call_commit_handler(dev);
/* Here, we will generate the appropriate event if needed */
return ret;
}
/* ---------------------------------------------------------------- */
/*
* Wrapper to call a private Wireless Extension handler.
* We do various checks and also take care of moving data between
* user space and kernel space.
* It's not as nice and slimline as the standard wrapper. The cause
* is struct iw_priv_args, which was not really designed for the
* job we are going here.
*
* IMPORTANT : This function prevent to set and get data on the same
* IOCTL and enforce the SET/GET convention. Not doing it would be
* far too hairy...
* If you need to set and get data at the same time, please don't use
* a iw_handler but process it in your ioctl handler (i.e. use the
* old driver API).
*/
static int get_priv_descr_and_size(struct net_device *dev, unsigned int cmd,
const struct iw_priv_args **descrp)
{
const struct iw_priv_args *descr;
int i, extra_size;
descr = NULL;
for (i = 0; i < dev->wireless_handlers->num_private_args; i++) {
if (cmd == dev->wireless_handlers->private_args[i].cmd) {
descr = &dev->wireless_handlers->private_args[i];
break;
}
}
extra_size = 0;
if (descr) {
if (IW_IS_SET(cmd)) {
int offset = 0; /* For sub-ioctls */
/* Check for sub-ioctl handler */
if (descr->name[0] == '\0')
/* Reserve one int for sub-ioctl index */
offset = sizeof(__u32);
/* Size of set arguments */
extra_size = get_priv_size(descr->set_args);
/* Does it fits in iwr ? */
if ((descr->set_args & IW_PRIV_SIZE_FIXED) &&
((extra_size + offset) <= IFNAMSIZ))
extra_size = 0;
} else {
/* Size of get arguments */
extra_size = get_priv_size(descr->get_args);
/* Does it fits in iwr ? */
if ((descr->get_args & IW_PRIV_SIZE_FIXED) &&
(extra_size <= IFNAMSIZ))
extra_size = 0;
}
}
*descrp = descr;
return extra_size;
}
static int ioctl_private_iw_point(struct iw_point *iwp, unsigned int cmd,
const struct iw_priv_args *descr,
iw_handler handler, struct net_device *dev,
struct iw_request_info *info, int extra_size)
{
char *extra;
int err;
/* Check what user space is giving us */
if (IW_IS_SET(cmd)) {
if (!iwp->pointer && iwp->length != 0)
return -EFAULT;
if (iwp->length > (descr->set_args & IW_PRIV_SIZE_MASK))
return -E2BIG;
} else if (!iwp->pointer)
return -EFAULT;
extra = kmalloc(extra_size, GFP_KERNEL);
if (!extra)
return -ENOMEM;
/* If it is a SET, get all the extra data in here */
if (IW_IS_SET(cmd) && (iwp->length != 0)) {
if (copy_from_user(extra, iwp->pointer, extra_size)) {
err = -EFAULT;
goto out;
}
}
/* Call the handler */
err = handler(dev, info, (union iwreq_data *) iwp, extra);
/* If we have something to return to the user */
if (!err && IW_IS_GET(cmd)) {
/* Adjust for the actual length if it's variable,
* avoid leaking kernel bits outside.
*/
if (!(descr->get_args & IW_PRIV_SIZE_FIXED))
extra_size = adjust_priv_size(descr->get_args, iwp);
if (copy_to_user(iwp->pointer, extra, extra_size))
err = -EFAULT;
}
out:
kfree(extra);
return err;
}
static int ioctl_private_call(struct net_device *dev, struct iwreq *iwr,
unsigned int cmd, struct iw_request_info *info,
iw_handler handler)
{
int extra_size = 0, ret = -EINVAL;
const struct iw_priv_args *descr;
extra_size = get_priv_descr_and_size(dev, cmd, &descr);
/* Check if we have a pointer to user space data or not. */
if (extra_size == 0) {
/* No extra arguments. Trivial to handle */
ret = handler(dev, info, &(iwr->u), (char *) &(iwr->u));
} else {
ret = ioctl_private_iw_point(&iwr->u.data, cmd, descr,
handler, dev, info, extra_size);
}
/* Call commit handler if needed and defined */
if (ret == -EIWCOMMIT)
ret = call_commit_handler(dev);
return ret;
}
/* ---------------------------------------------------------------- */
typedef int (*wext_ioctl_func)(struct net_device *, struct iwreq *,
unsigned int, struct iw_request_info *,
iw_handler);
/*
* Main IOCTl dispatcher.
* Check the type of IOCTL and call the appropriate wrapper...
*/
static int wireless_process_ioctl(struct net *net, struct ifreq *ifr,
unsigned int cmd,
struct iw_request_info *info,
wext_ioctl_func standard,
wext_ioctl_func private)
{
struct iwreq *iwr = (struct iwreq *) ifr;
struct net_device *dev;
iw_handler handler;
/* Permissions are already checked in dev_ioctl() before calling us.
* The copy_to/from_user() of ifr is also dealt with in there */
/* Make sure the device exist */
if ((dev = __dev_get_by_name(net, ifr->ifr_name)) == NULL)
return -ENODEV;
/* A bunch of special cases, then the generic case...
* Note that 'cmd' is already filtered in dev_ioctl() with
* (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST) */
if (cmd == SIOCGIWSTATS)
return standard(dev, iwr, cmd, info,
&iw_handler_get_iwstats);
if (cmd == SIOCGIWPRIV && dev->wireless_handlers)
return standard(dev, iwr, cmd, info,
&iw_handler_get_private);
/* Basic check */
if (!netif_device_present(dev))
return -ENODEV;
/* New driver API : try to find the handler */
handler = get_handler(dev, cmd);
if (handler) {
/* Standard and private are not the same */
if (cmd < SIOCIWFIRSTPRIV)
return standard(dev, iwr, cmd, info, handler);
else
return private(dev, iwr, cmd, info, handler);
}
/* Old driver API : call driver ioctl handler */
if (dev->netdev_ops->ndo_do_ioctl)
return dev->netdev_ops->ndo_do_ioctl(dev, ifr, cmd);
return -EOPNOTSUPP;
}
/* If command is `set a parameter', or `get the encoding parameters',
* check if the user has the right to do it.
*/
static int wext_permission_check(unsigned int cmd)
{
if ((IW_IS_SET(cmd) || cmd == SIOCGIWENCODE || cmd == SIOCGIWENCODEEXT)
&& !capable(CAP_NET_ADMIN))
return -EPERM;
return 0;
}
/* entry point from dev ioctl */
static int wext_ioctl_dispatch(struct net *net, struct ifreq *ifr,
unsigned int cmd, struct iw_request_info *info,
wext_ioctl_func standard,
wext_ioctl_func private)
{
int ret = wext_permission_check(cmd);
if (ret)
return ret;
dev_load(net, ifr->ifr_name);
rtnl_lock();
ret = wireless_process_ioctl(net, ifr, cmd, info, standard, private);
rtnl_unlock();
return ret;
}
int wext_handle_ioctl(struct net *net, struct ifreq *ifr, unsigned int cmd,
void __user *arg)
{
struct iw_request_info info = { .cmd = cmd, .flags = 0 };
int ret;
ret = wext_ioctl_dispatch(net, ifr, cmd, &info,
ioctl_standard_call,
ioctl_private_call);
if (ret >= 0 &&
IW_IS_GET(cmd) &&
copy_to_user(arg, ifr, sizeof(struct iwreq)))
return -EFAULT;
return ret;
}
#ifdef CONFIG_COMPAT
static int compat_standard_call(struct net_device *dev,
struct iwreq *iwr,
unsigned int cmd,
struct iw_request_info *info,
iw_handler handler)
{
const struct iw_ioctl_description *descr;
struct compat_iw_point *iwp_compat;
struct iw_point iwp;
int err;
descr = standard_ioctl + (cmd - SIOCIWFIRST);
if (descr->header_type != IW_HEADER_TYPE_POINT)
return ioctl_standard_call(dev, iwr, cmd, info, handler);
iwp_compat = (struct compat_iw_point *) &iwr->u.data;
iwp.pointer = compat_ptr(iwp_compat->pointer);
iwp.length = iwp_compat->length;
iwp.flags = iwp_compat->flags;
err = ioctl_standard_iw_point(&iwp, cmd, descr, handler, dev, info);
iwp_compat->pointer = ptr_to_compat(iwp.pointer);
iwp_compat->length = iwp.length;
iwp_compat->flags = iwp.flags;
return err;
}
static int compat_private_call(struct net_device *dev, struct iwreq *iwr,
unsigned int cmd, struct iw_request_info *info,
iw_handler handler)
{
const struct iw_priv_args *descr;
int ret, extra_size;
extra_size = get_priv_descr_and_size(dev, cmd, &descr);
/* Check if we have a pointer to user space data or not. */
if (extra_size == 0) {
/* No extra arguments. Trivial to handle */
ret = handler(dev, info, &(iwr->u), (char *) &(iwr->u));
} else {
struct compat_iw_point *iwp_compat;
struct iw_point iwp;
iwp_compat = (struct compat_iw_point *) &iwr->u.data;
iwp.pointer = compat_ptr(iwp_compat->pointer);
iwp.length = iwp_compat->length;
iwp.flags = iwp_compat->flags;
ret = ioctl_private_iw_point(&iwp, cmd, descr,
handler, dev, info, extra_size);
iwp_compat->pointer = ptr_to_compat(iwp.pointer);
iwp_compat->length = iwp.length;
iwp_compat->flags = iwp.flags;
}
/* Call commit handler if needed and defined */
if (ret == -EIWCOMMIT)
ret = call_commit_handler(dev);
return ret;
}
int compat_wext_handle_ioctl(struct net *net, unsigned int cmd,
unsigned long arg)
{
void __user *argp = (void __user *)arg;
struct iw_request_info info;
struct iwreq iwr;
char *colon;
int ret;
if (copy_from_user(&iwr, argp, sizeof(struct iwreq)))
return -EFAULT;
iwr.ifr_name[IFNAMSIZ-1] = 0;
colon = strchr(iwr.ifr_name, ':');
if (colon)
*colon = 0;
info.cmd = cmd;
info.flags = IW_REQUEST_FLAG_COMPAT;
ret = wext_ioctl_dispatch(net, (struct ifreq *) &iwr, cmd, &info,
compat_standard_call,
compat_private_call);
if (ret >= 0 &&
IW_IS_GET(cmd) &&
copy_to_user(argp, &iwr, sizeof(struct iwreq)))
return -EFAULT;
return ret;
}
#endif
static int __net_init wext_pernet_init(struct net *net)
{
skb_queue_head_init(&net->wext_nlevents);
return 0;
}
static void __net_exit wext_pernet_exit(struct net *net)
{
skb_queue_purge(&net->wext_nlevents);
}
static struct pernet_operations wext_pernet_ops = {
.init = wext_pernet_init,
.exit = wext_pernet_exit,
};
static int __init wireless_nlevent_init(void)
{
return register_pernet_subsys(&wext_pernet_ops);
return 0;
}
subsys_initcall(wireless_nlevent_init);
/* Process events generated by the wireless layer or the driver. */
static void wireless_nlevent_process(struct work_struct *work)
{
struct sk_buff *skb;
struct net *net;
rtnl_lock();
for_each_net(net) {
while ((skb = skb_dequeue(&net->wext_nlevents)))
rtnl_notify(skb, net, 0, RTNLGRP_LINK, NULL,
GFP_KERNEL);
}
rtnl_unlock();
}
static DECLARE_WORK(wireless_nlevent_work, wireless_nlevent_process);
static struct nlmsghdr *rtnetlink_ifinfo_prep(struct net_device *dev,
struct sk_buff *skb)
{
struct ifinfomsg *r;
struct nlmsghdr *nlh;
nlh = nlmsg_put(skb, 0, 0, RTM_NEWLINK, sizeof(*r), 0);
if (!nlh)
return NULL;
r = nlmsg_data(nlh);
r->ifi_family = AF_UNSPEC;
r->__ifi_pad = 0;
r->ifi_type = dev->type;
r->ifi_index = dev->ifindex;
r->ifi_flags = dev_get_flags(dev);
r->ifi_change = 0; /* Wireless changes don't affect those flags */
NLA_PUT_STRING(skb, IFLA_IFNAME, dev->name);
return nlh;
nla_put_failure:
nlmsg_cancel(skb, nlh);
return NULL;
}
/*
* Main event dispatcher. Called from other parts and drivers.
* Send the event on the appropriate channels.
* May be called from interrupt context.
*/
void wireless_send_event(struct net_device * dev,
unsigned int cmd,
union iwreq_data * wrqu,
const char * extra)
{
const struct iw_ioctl_description * descr = NULL;
int extra_len = 0;
struct iw_event *event; /* Mallocated whole event */
int event_len; /* Its size */
int hdr_len; /* Size of the event header */
int wrqu_off = 0; /* Offset in wrqu */
/* Don't "optimise" the following variable, it will crash */
unsigned cmd_index; /* *MUST* be unsigned */
struct sk_buff *skb;
struct nlmsghdr *nlh;
struct nlattr *nla;
#ifdef CONFIG_COMPAT
struct __compat_iw_event *compat_event;
struct compat_iw_point compat_wrqu;
struct sk_buff *compskb;
#endif
/*
* Nothing in the kernel sends scan events with data, be safe.
* This is necessary because we cannot fix up scan event data
* for compat, due to being contained in 'extra', but normally
* applications are required to retrieve the scan data anyway
* and no data is included in the event, this codifies that
* practice.
*/
if (WARN_ON(cmd == SIOCGIWSCAN && extra))
extra = NULL;
/* Get the description of the Event */
if (cmd <= SIOCIWLAST) {
cmd_index = cmd - SIOCIWFIRST;
if (cmd_index < standard_ioctl_num)
descr = &(standard_ioctl[cmd_index]);
} else {
cmd_index = cmd - IWEVFIRST;
if (cmd_index < standard_event_num)
descr = &(standard_event[cmd_index]);
}
/* Don't accept unknown events */
if (descr == NULL) {
/* Note : we don't return an error to the driver, because
* the driver would not know what to do about it. It can't
* return an error to the user, because the event is not
* initiated by a user request.
* The best the driver could do is to log an error message.
* We will do it ourselves instead...
*/
printk(KERN_ERR "%s (WE) : Invalid/Unknown Wireless Event (0x%04X)\n",
dev->name, cmd);
return;
}
/* Check extra parameters and set extra_len */
if (descr->header_type == IW_HEADER_TYPE_POINT) {
/* Check if number of token fits within bounds */
if (wrqu->data.length > descr->max_tokens) {
printk(KERN_ERR "%s (WE) : Wireless Event too big (%d)\n", dev->name, wrqu->data.length);
return;
}
if (wrqu->data.length < descr->min_tokens) {
printk(KERN_ERR "%s (WE) : Wireless Event too small (%d)\n", dev->name, wrqu->data.length);
return;
}
/* Calculate extra_len - extra is NULL for restricted events */
if (extra != NULL)
extra_len = wrqu->data.length * descr->token_size;
/* Always at an offset in wrqu */
wrqu_off = IW_EV_POINT_OFF;
}
/* Total length of the event */
hdr_len = event_type_size[descr->header_type];
event_len = hdr_len + extra_len;
/*
* The problem for 64/32 bit.
*
* On 64-bit, a regular event is laid out as follows:
* | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
* | event.len | event.cmd | p a d d i n g |
* | wrqu data ... (with the correct size) |
*
* This padding exists because we manipulate event->u,
* and 'event' is not packed.
*
* An iw_point event is laid out like this instead:
* | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
* | event.len | event.cmd | p a d d i n g |
* | iwpnt.len | iwpnt.flg | p a d d i n g |
* | extra data ...
*
* The second padding exists because struct iw_point is extended,
* but this depends on the platform...
*
* On 32-bit, all the padding shouldn't be there.
*/
skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
if (!skb)
return;
/* Send via the RtNetlink event channel */
nlh = rtnetlink_ifinfo_prep(dev, skb);
if (WARN_ON(!nlh)) {
kfree_skb(skb);
return;
}
/* Add the wireless events in the netlink packet */
nla = nla_reserve(skb, IFLA_WIRELESS, event_len);
if (!nla) {
kfree_skb(skb);
return;
}
event = nla_data(nla);
/* Fill event - first clear to avoid data leaking */
memset(event, 0, hdr_len);
event->len = event_len;
event->cmd = cmd;
memcpy(&event->u, ((char *) wrqu) + wrqu_off, hdr_len - IW_EV_LCP_LEN);
if (extra_len)
memcpy(((char *) event) + hdr_len, extra, extra_len);
nlmsg_end(skb, nlh);
#ifdef CONFIG_COMPAT
hdr_len = compat_event_type_size[descr->header_type];
event_len = hdr_len + extra_len;
compskb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
if (!compskb) {
kfree_skb(skb);
return;
}
/* Send via the RtNetlink event channel */
nlh = rtnetlink_ifinfo_prep(dev, compskb);
if (WARN_ON(!nlh)) {
kfree_skb(skb);
kfree_skb(compskb);
return;
}
/* Add the wireless events in the netlink packet */
nla = nla_reserve(compskb, IFLA_WIRELESS, event_len);
if (!nla) {
kfree_skb(skb);
kfree_skb(compskb);
return;
}
compat_event = nla_data(nla);
compat_event->len = event_len;
compat_event->cmd = cmd;
if (descr->header_type == IW_HEADER_TYPE_POINT) {
compat_wrqu.length = wrqu->data.length;
compat_wrqu.flags = wrqu->data.flags;
memcpy(&compat_event->pointer,
((char *) &compat_wrqu) + IW_EV_COMPAT_POINT_OFF,
hdr_len - IW_EV_COMPAT_LCP_LEN);
if (extra_len)
memcpy(((char *) compat_event) + hdr_len,
extra, extra_len);
} else {
/* extra_len must be zero, so no if (extra) needed */
memcpy(&compat_event->pointer, wrqu,
hdr_len - IW_EV_COMPAT_LCP_LEN);
}
nlmsg_end(compskb, nlh);
skb_shinfo(skb)->frag_list = compskb;
#endif
skb_queue_tail(&dev_net(dev)->wext_nlevents, skb);
schedule_work(&wireless_nlevent_work);
}
EXPORT_SYMBOL(wireless_send_event);
/********************** ENHANCED IWSPY SUPPORT **********************/
/*
* In the old days, the driver was handling spy support all by itself.
* Now, the driver can delegate this task to Wireless Extensions.
* It needs to use those standard spy iw_handler in struct iw_handler_def,
* push data to us via wireless_spy_update() and include struct iw_spy_data
* in its private part (and export it in net_device->wireless_data->spy_data).
* One of the main advantage of centralising spy support here is that
* it becomes much easier to improve and extend it without having to touch
* the drivers. One example is the addition of the Spy-Threshold events.
*/
/* ---------------------------------------------------------------- */
/*
* Return the pointer to the spy data in the driver.
* Because this is called on the Rx path via wireless_spy_update(),
* we want it to be efficient...
*/
static inline struct iw_spy_data *get_spydata(struct net_device *dev)
{
/* This is the new way */
if (dev->wireless_data)
return dev->wireless_data->spy_data;
return NULL;
}
/*------------------------------------------------------------------*/
/*
* Standard Wireless Handler : set Spy List
*/
int iw_handler_set_spy(struct net_device * dev,
struct iw_request_info * info,
union iwreq_data * wrqu,
char * extra)
{
struct iw_spy_data * spydata = get_spydata(dev);
struct sockaddr * address = (struct sockaddr *) extra;
/* Make sure driver is not buggy or using the old API */
if (!spydata)
return -EOPNOTSUPP;
/* Disable spy collection while we copy the addresses.
* While we copy addresses, any call to wireless_spy_update()
* will NOP. This is OK, as anyway the addresses are changing. */
spydata->spy_number = 0;
/* We want to operate without locking, because wireless_spy_update()
* most likely will happen in the interrupt handler, and therefore
* have its own locking constraints and needs performance.
* The rtnl_lock() make sure we don't race with the other iw_handlers.
* This make sure wireless_spy_update() "see" that the spy list
* is temporarily disabled. */
smp_wmb();
/* Are there are addresses to copy? */
if (wrqu->data.length > 0) {
int i;
/* Copy addresses */
for (i = 0; i < wrqu->data.length; i++)
memcpy(spydata->spy_address[i], address[i].sa_data,
ETH_ALEN);
/* Reset stats */
memset(spydata->spy_stat, 0,
sizeof(struct iw_quality) * IW_MAX_SPY);
}
/* Make sure above is updated before re-enabling */
smp_wmb();
/* Enable addresses */
spydata->spy_number = wrqu->data.length;
return 0;
}
EXPORT_SYMBOL(iw_handler_set_spy);
/*------------------------------------------------------------------*/
/*
* Standard Wireless Handler : get Spy List
*/
int iw_handler_get_spy(struct net_device * dev,
struct iw_request_info * info,
union iwreq_data * wrqu,
char * extra)
{
struct iw_spy_data * spydata = get_spydata(dev);
struct sockaddr * address = (struct sockaddr *) extra;
int i;
/* Make sure driver is not buggy or using the old API */
if (!spydata)
return -EOPNOTSUPP;
wrqu->data.length = spydata->spy_number;
/* Copy addresses. */
for (i = 0; i < spydata->spy_number; i++) {
memcpy(address[i].sa_data, spydata->spy_address[i], ETH_ALEN);
address[i].sa_family = AF_UNIX;
}
/* Copy stats to the user buffer (just after). */
if (spydata->spy_number > 0)
memcpy(extra + (sizeof(struct sockaddr) *spydata->spy_number),
spydata->spy_stat,
sizeof(struct iw_quality) * spydata->spy_number);
/* Reset updated flags. */
for (i = 0; i < spydata->spy_number; i++)
spydata->spy_stat[i].updated &= ~IW_QUAL_ALL_UPDATED;
return 0;
}
EXPORT_SYMBOL(iw_handler_get_spy);
/*------------------------------------------------------------------*/
/*
* Standard Wireless Handler : set spy threshold
*/
int iw_handler_set_thrspy(struct net_device * dev,
struct iw_request_info *info,
union iwreq_data * wrqu,
char * extra)
{
struct iw_spy_data * spydata = get_spydata(dev);
struct iw_thrspy * threshold = (struct iw_thrspy *) extra;
/* Make sure driver is not buggy or using the old API */
if (!spydata)
return -EOPNOTSUPP;
/* Just do it */
memcpy(&(spydata->spy_thr_low), &(threshold->low),
2 * sizeof(struct iw_quality));
/* Clear flag */
memset(spydata->spy_thr_under, '\0', sizeof(spydata->spy_thr_under));
return 0;
}
EXPORT_SYMBOL(iw_handler_set_thrspy);
/*------------------------------------------------------------------*/
/*
* Standard Wireless Handler : get spy threshold
*/
int iw_handler_get_thrspy(struct net_device * dev,
struct iw_request_info *info,
union iwreq_data * wrqu,
char * extra)
{
struct iw_spy_data * spydata = get_spydata(dev);
struct iw_thrspy * threshold = (struct iw_thrspy *) extra;
/* Make sure driver is not buggy or using the old API */
if (!spydata)
return -EOPNOTSUPP;
/* Just do it */
memcpy(&(threshold->low), &(spydata->spy_thr_low),
2 * sizeof(struct iw_quality));
return 0;
}
EXPORT_SYMBOL(iw_handler_get_thrspy);
/*------------------------------------------------------------------*/
/*
* Prepare and send a Spy Threshold event
*/
static void iw_send_thrspy_event(struct net_device * dev,
struct iw_spy_data * spydata,
unsigned char * address,
struct iw_quality * wstats)
{
union iwreq_data wrqu;
struct iw_thrspy threshold;
/* Init */
wrqu.data.length = 1;
wrqu.data.flags = 0;
/* Copy address */
memcpy(threshold.addr.sa_data, address, ETH_ALEN);
threshold.addr.sa_family = ARPHRD_ETHER;
/* Copy stats */
memcpy(&(threshold.qual), wstats, sizeof(struct iw_quality));
/* Copy also thresholds */
memcpy(&(threshold.low), &(spydata->spy_thr_low),
2 * sizeof(struct iw_quality));
/* Send event to user space */
wireless_send_event(dev, SIOCGIWTHRSPY, &wrqu, (char *) &threshold);
}
/* ---------------------------------------------------------------- */
/*
* Call for the driver to update the spy data.
* For now, the spy data is a simple array. As the size of the array is
* small, this is good enough. If we wanted to support larger number of
* spy addresses, we should use something more efficient...
*/
void wireless_spy_update(struct net_device * dev,
unsigned char * address,
struct iw_quality * wstats)
{
struct iw_spy_data * spydata = get_spydata(dev);
int i;
int match = -1;
/* Make sure driver is not buggy or using the old API */
if (!spydata)
return;
/* Update all records that match */
for (i = 0; i < spydata->spy_number; i++)
if (!compare_ether_addr(address, spydata->spy_address[i])) {
memcpy(&(spydata->spy_stat[i]), wstats,
sizeof(struct iw_quality));
match = i;
}
/* Generate an event if we cross the spy threshold.
* To avoid event storms, we have a simple hysteresis : we generate
* event only when we go under the low threshold or above the
* high threshold. */
if (match >= 0) {
if (spydata->spy_thr_under[match]) {
if (wstats->level > spydata->spy_thr_high.level) {
spydata->spy_thr_under[match] = 0;
iw_send_thrspy_event(dev, spydata,
address, wstats);
}
} else {
if (wstats->level < spydata->spy_thr_low.level) {
spydata->spy_thr_under[match] = 1;
iw_send_thrspy_event(dev, spydata,
address, wstats);
}
}
}
}
EXPORT_SYMBOL(wireless_spy_update);
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