637 строки
24 KiB
C
637 строки
24 KiB
C
/*
|
|
* This file define the new driver API for Wireless Extensions
|
|
*
|
|
* Version : 8 16.3.07
|
|
*
|
|
* Authors : Jean Tourrilhes - HPL - <jt@hpl.hp.com>
|
|
* Copyright (c) 2001-2007 Jean Tourrilhes, All Rights Reserved.
|
|
*/
|
|
|
|
#ifndef _IW_HANDLER_H
|
|
#define _IW_HANDLER_H
|
|
|
|
/************************** DOCUMENTATION **************************/
|
|
/*
|
|
* Initial driver API (1996 -> onward) :
|
|
* -----------------------------------
|
|
* The initial API just sends the IOCTL request received from user space
|
|
* to the driver (via the driver ioctl handler). The driver has to
|
|
* handle all the rest...
|
|
*
|
|
* The initial API also defines a specific handler in struct net_device
|
|
* to handle wireless statistics.
|
|
*
|
|
* The initial APIs served us well and has proven a reasonably good design.
|
|
* However, there is a few shortcommings :
|
|
* o No events, everything is a request to the driver.
|
|
* o Large ioctl function in driver with gigantic switch statement
|
|
* (i.e. spaghetti code).
|
|
* o Driver has to mess up with copy_to/from_user, and in many cases
|
|
* does it unproperly. Common mistakes are :
|
|
* * buffer overflows (no checks or off by one checks)
|
|
* * call copy_to/from_user with irq disabled
|
|
* o The user space interface is tied to ioctl because of the use
|
|
* copy_to/from_user.
|
|
*
|
|
* New driver API (2002 -> onward) :
|
|
* -------------------------------
|
|
* The new driver API is just a bunch of standard functions (handlers),
|
|
* each handling a specific Wireless Extension. The driver just export
|
|
* the list of handler it supports, and those will be called apropriately.
|
|
*
|
|
* I tried to keep the main advantage of the previous API (simplicity,
|
|
* efficiency and light weight), and also I provide a good dose of backward
|
|
* compatibility (most structures are the same, driver can use both API
|
|
* simultaneously, ...).
|
|
* Hopefully, I've also addressed the shortcomming of the initial API.
|
|
*
|
|
* The advantage of the new API are :
|
|
* o Handling of Extensions in driver broken in small contained functions
|
|
* o Tighter checks of ioctl before calling the driver
|
|
* o Flexible commit strategy (at least, the start of it)
|
|
* o Backward compatibility (can be mixed with old API)
|
|
* o Driver doesn't have to worry about memory and user-space issues
|
|
* The last point is important for the following reasons :
|
|
* o You are now able to call the new driver API from any API you
|
|
* want (including from within other parts of the kernel).
|
|
* o Common mistakes are avoided (buffer overflow, user space copy
|
|
* with irq disabled and so on).
|
|
*
|
|
* The Drawback of the new API are :
|
|
* o bloat (especially kernel)
|
|
* o need to migrate existing drivers to new API
|
|
* My initial testing shows that the new API adds around 3kB to the kernel
|
|
* and save between 0 and 5kB from a typical driver.
|
|
* Also, as all structures and data types are unchanged, the migration is
|
|
* quite straightforward (but tedious).
|
|
*
|
|
* ---
|
|
*
|
|
* The new driver API is defined below in this file. User space should
|
|
* not be aware of what's happening down there...
|
|
*
|
|
* A new kernel wrapper is in charge of validating the IOCTLs and calling
|
|
* the appropriate driver handler. This is implemented in :
|
|
* # net/core/wireless.c
|
|
*
|
|
* The driver export the list of handlers in :
|
|
* # include/linux/netdevice.h (one place)
|
|
*
|
|
* The new driver API is available for WIRELESS_EXT >= 13.
|
|
* Good luck with migration to the new API ;-)
|
|
*/
|
|
|
|
/* ---------------------- THE IMPLEMENTATION ---------------------- */
|
|
/*
|
|
* Some of the choice I've made are pretty controversials. Defining an
|
|
* API is very much weighting compromises. This goes into some of the
|
|
* details and the thinking behind the implementation.
|
|
*
|
|
* Implementation goals :
|
|
* --------------------
|
|
* The implementation goals were as follow :
|
|
* o Obvious : you should not need a PhD to understand what's happening,
|
|
* the benefit is easier maintainance.
|
|
* o Flexible : it should accommodate a wide variety of driver
|
|
* implementations and be as flexible as the old API.
|
|
* o Lean : it should be efficient memory wise to minimise the impact
|
|
* on kernel footprint.
|
|
* o Transparent to user space : the large number of user space
|
|
* applications that use Wireless Extensions should not need
|
|
* any modifications.
|
|
*
|
|
* Array of functions versus Struct of functions
|
|
* ---------------------------------------------
|
|
* 1) Having an array of functions allow the kernel code to access the
|
|
* handler in a single lookup, which is much more efficient (think hash
|
|
* table here).
|
|
* 2) The only drawback is that driver writer may put their handler in
|
|
* the wrong slot. This is trivial to test (I set the frequency, the
|
|
* bitrate changes). Once the handler is in the proper slot, it will be
|
|
* there forever, because the array is only extended at the end.
|
|
* 3) Backward/forward compatibility : adding new handler just require
|
|
* extending the array, so you can put newer driver in older kernel
|
|
* without having to patch the kernel code (and vice versa).
|
|
*
|
|
* All handler are of the same generic type
|
|
* ----------------------------------------
|
|
* That's a feature !!!
|
|
* 1) Having a generic handler allow to have generic code, which is more
|
|
* efficient. If each of the handler was individually typed I would need
|
|
* to add a big switch in the kernel (== more bloat). This solution is
|
|
* more scalable, adding new Wireless Extensions doesn't add new code.
|
|
* 2) You can use the same handler in different slots of the array. For
|
|
* hardware, it may be more efficient or logical to handle multiple
|
|
* Wireless Extensions with a single function, and the API allow you to
|
|
* do that. (An example would be a single record on the card to control
|
|
* both bitrate and frequency, the handler would read the old record,
|
|
* modify it according to info->cmd and rewrite it).
|
|
*
|
|
* Functions prototype uses union iwreq_data
|
|
* -----------------------------------------
|
|
* Some would have prefered functions defined this way :
|
|
* static int mydriver_ioctl_setrate(struct net_device *dev,
|
|
* long rate, int auto)
|
|
* 1) The kernel code doesn't "validate" the content of iwreq_data, and
|
|
* can't do it (different hardware may have different notion of what a
|
|
* valid frequency is), so we don't pretend that we do it.
|
|
* 2) The above form is not extendable. If I want to add a flag (for
|
|
* example to distinguish setting max rate and basic rate), I would
|
|
* break the prototype. Using iwreq_data is more flexible.
|
|
* 3) Also, the above form is not generic (see above).
|
|
* 4) I don't expect driver developper using the wrong field of the
|
|
* union (Doh !), so static typechecking doesn't add much value.
|
|
* 5) Lastly, you can skip the union by doing :
|
|
* static int mydriver_ioctl_setrate(struct net_device *dev,
|
|
* struct iw_request_info *info,
|
|
* struct iw_param *rrq,
|
|
* char *extra)
|
|
* And then adding the handler in the array like this :
|
|
* (iw_handler) mydriver_ioctl_setrate, // SIOCSIWRATE
|
|
*
|
|
* Using functions and not a registry
|
|
* ----------------------------------
|
|
* Another implementation option would have been for every instance to
|
|
* define a registry (a struct containing all the Wireless Extensions)
|
|
* and only have a function to commit the registry to the hardware.
|
|
* 1) This approach can be emulated by the current code, but not
|
|
* vice versa.
|
|
* 2) Some drivers don't keep any configuration in the driver, for them
|
|
* adding such a registry would be a significant bloat.
|
|
* 3) The code to translate from Wireless Extension to native format is
|
|
* needed anyway, so it would not reduce significantely the amount of code.
|
|
* 4) The current approach only selectively translate Wireless Extensions
|
|
* to native format and only selectively set, whereas the registry approach
|
|
* would require to translate all WE and set all parameters for any single
|
|
* change.
|
|
* 5) For many Wireless Extensions, the GET operation return the current
|
|
* dynamic value, not the value that was set.
|
|
*
|
|
* This header is <net/iw_handler.h>
|
|
* ---------------------------------
|
|
* 1) This header is kernel space only and should not be exported to
|
|
* user space. Headers in "include/linux/" are exported, headers in
|
|
* "include/net/" are not.
|
|
*
|
|
* Mixed 32/64 bit issues
|
|
* ----------------------
|
|
* The Wireless Extensions are designed to be 64 bit clean, by using only
|
|
* datatypes with explicit storage size.
|
|
* There are some issues related to kernel and user space using different
|
|
* memory model, and in particular 64bit kernel with 32bit user space.
|
|
* The problem is related to struct iw_point, that contains a pointer
|
|
* that *may* need to be translated.
|
|
* This is quite messy. The new API doesn't solve this problem (it can't),
|
|
* but is a step in the right direction :
|
|
* 1) Meta data about each ioctl is easily available, so we know what type
|
|
* of translation is needed.
|
|
* 2) The move of data between kernel and user space is only done in a single
|
|
* place in the kernel, so adding specific hooks in there is possible.
|
|
* 3) In the long term, it allows to move away from using ioctl as the
|
|
* user space API.
|
|
*
|
|
* So many comments and so few code
|
|
* --------------------------------
|
|
* That's a feature. Comments won't bloat the resulting kernel binary.
|
|
*/
|
|
|
|
/***************************** INCLUDES *****************************/
|
|
|
|
#include <linux/wireless.h> /* IOCTL user space API */
|
|
#include <linux/if_ether.h>
|
|
|
|
/***************************** VERSION *****************************/
|
|
/*
|
|
* This constant is used to know which version of the driver API is
|
|
* available. Hopefully, this will be pretty stable and no changes
|
|
* will be needed...
|
|
* I just plan to increment with each new version.
|
|
*/
|
|
#define IW_HANDLER_VERSION 8
|
|
|
|
/*
|
|
* Changes :
|
|
*
|
|
* V2 to V3
|
|
* --------
|
|
* - Move event definition in <linux/wireless.h>
|
|
* - Add Wireless Event support :
|
|
* o wireless_send_event() prototype
|
|
* o iwe_stream_add_event/point() inline functions
|
|
* V3 to V4
|
|
* --------
|
|
* - Reshuffle IW_HEADER_TYPE_XXX to map IW_PRIV_TYPE_XXX changes
|
|
*
|
|
* V4 to V5
|
|
* --------
|
|
* - Add new spy support : struct iw_spy_data & prototypes
|
|
*
|
|
* V5 to V6
|
|
* --------
|
|
* - Change the way we get to spy_data method for added safety
|
|
* - Remove spy #ifdef, they are always on -> cleaner code
|
|
* - Add IW_DESCR_FLAG_NOMAX flag for very large requests
|
|
* - Start migrating get_wireless_stats to struct iw_handler_def
|
|
*
|
|
* V6 to V7
|
|
* --------
|
|
* - Add struct ieee80211_device pointer in struct iw_public_data
|
|
* - Remove (struct iw_point *)->pointer from events and streams
|
|
* - Remove spy_offset from struct iw_handler_def
|
|
* - Add "check" version of event macros for ieee802.11 stack
|
|
*
|
|
* V7 to V8
|
|
* ----------
|
|
* - Prevent leaking of kernel space in stream on 64 bits.
|
|
*/
|
|
|
|
/**************************** CONSTANTS ****************************/
|
|
|
|
/* Enhanced spy support available */
|
|
#define IW_WIRELESS_SPY
|
|
#define IW_WIRELESS_THRSPY
|
|
|
|
/* Special error message for the driver to indicate that we
|
|
* should do a commit after return from the iw_handler */
|
|
#define EIWCOMMIT EINPROGRESS
|
|
|
|
/* Flags available in struct iw_request_info */
|
|
#define IW_REQUEST_FLAG_NONE 0x0000 /* No flag so far */
|
|
|
|
/* Type of headers we know about (basically union iwreq_data) */
|
|
#define IW_HEADER_TYPE_NULL 0 /* Not available */
|
|
#define IW_HEADER_TYPE_CHAR 2 /* char [IFNAMSIZ] */
|
|
#define IW_HEADER_TYPE_UINT 4 /* __u32 */
|
|
#define IW_HEADER_TYPE_FREQ 5 /* struct iw_freq */
|
|
#define IW_HEADER_TYPE_ADDR 6 /* struct sockaddr */
|
|
#define IW_HEADER_TYPE_POINT 8 /* struct iw_point */
|
|
#define IW_HEADER_TYPE_PARAM 9 /* struct iw_param */
|
|
#define IW_HEADER_TYPE_QUAL 10 /* struct iw_quality */
|
|
|
|
/* Handling flags */
|
|
/* Most are not implemented. I just use them as a reminder of some
|
|
* cool features we might need one day ;-) */
|
|
#define IW_DESCR_FLAG_NONE 0x0000 /* Obvious */
|
|
/* Wrapper level flags */
|
|
#define IW_DESCR_FLAG_DUMP 0x0001 /* Not part of the dump command */
|
|
#define IW_DESCR_FLAG_EVENT 0x0002 /* Generate an event on SET */
|
|
#define IW_DESCR_FLAG_RESTRICT 0x0004 /* GET : request is ROOT only */
|
|
/* SET : Omit payload from generated iwevent */
|
|
#define IW_DESCR_FLAG_NOMAX 0x0008 /* GET : no limit on request size */
|
|
/* Driver level flags */
|
|
#define IW_DESCR_FLAG_WAIT 0x0100 /* Wait for driver event */
|
|
|
|
/****************************** TYPES ******************************/
|
|
|
|
/* ----------------------- WIRELESS HANDLER ----------------------- */
|
|
/*
|
|
* A wireless handler is just a standard function, that looks like the
|
|
* ioctl handler.
|
|
* We also define there how a handler list look like... As the Wireless
|
|
* Extension space is quite dense, we use a simple array, which is faster
|
|
* (that's the perfect hash table ;-).
|
|
*/
|
|
|
|
/*
|
|
* Meta data about the request passed to the iw_handler.
|
|
* Most handlers can safely ignore what's in there.
|
|
* The 'cmd' field might come handy if you want to use the same handler
|
|
* for multiple command...
|
|
* This struct is also my long term insurance. I can add new fields here
|
|
* without breaking the prototype of iw_handler...
|
|
*/
|
|
struct iw_request_info
|
|
{
|
|
__u16 cmd; /* Wireless Extension command */
|
|
__u16 flags; /* More to come ;-) */
|
|
};
|
|
|
|
struct net_device;
|
|
|
|
/*
|
|
* This is how a function handling a Wireless Extension should look
|
|
* like (both get and set, standard and private).
|
|
*/
|
|
typedef int (*iw_handler)(struct net_device *dev, struct iw_request_info *info,
|
|
union iwreq_data *wrqu, char *extra);
|
|
|
|
/*
|
|
* This define all the handler that the driver export.
|
|
* As you need only one per driver type, please use a static const
|
|
* shared by all driver instances... Same for the members...
|
|
* This will be linked from net_device in <linux/netdevice.h>
|
|
*/
|
|
struct iw_handler_def
|
|
{
|
|
/* Number of handlers defined (more precisely, index of the
|
|
* last defined handler + 1) */
|
|
__u16 num_standard;
|
|
__u16 num_private;
|
|
/* Number of private arg description */
|
|
__u16 num_private_args;
|
|
|
|
/* Array of handlers for standard ioctls
|
|
* We will call dev->wireless_handlers->standard[ioctl - SIOCSIWCOMMIT]
|
|
*/
|
|
const iw_handler * standard;
|
|
|
|
/* Array of handlers for private ioctls
|
|
* Will call dev->wireless_handlers->private[ioctl - SIOCIWFIRSTPRIV]
|
|
*/
|
|
const iw_handler * private;
|
|
|
|
/* Arguments of private handler. This one is just a list, so you
|
|
* can put it in any order you want and should not leave holes...
|
|
* We will automatically export that to user space... */
|
|
const struct iw_priv_args * private_args;
|
|
|
|
/* New location of get_wireless_stats, to de-bloat struct net_device.
|
|
* The old pointer in struct net_device will be gradually phased
|
|
* out, and drivers are encouraged to use this one... */
|
|
struct iw_statistics* (*get_wireless_stats)(struct net_device *dev);
|
|
};
|
|
|
|
/* ---------------------- IOCTL DESCRIPTION ---------------------- */
|
|
/*
|
|
* One of the main goal of the new interface is to deal entirely with
|
|
* user space/kernel space memory move.
|
|
* For that, we need to know :
|
|
* o if iwreq is a pointer or contain the full data
|
|
* o what is the size of the data to copy
|
|
*
|
|
* For private IOCTLs, we use the same rules as used by iwpriv and
|
|
* defined in struct iw_priv_args.
|
|
*
|
|
* For standard IOCTLs, things are quite different and we need to
|
|
* use the stuctures below. Actually, this struct is also more
|
|
* efficient, but that's another story...
|
|
*/
|
|
|
|
/*
|
|
* Describe how a standard IOCTL looks like.
|
|
*/
|
|
struct iw_ioctl_description
|
|
{
|
|
__u8 header_type; /* NULL, iw_point or other */
|
|
__u8 token_type; /* Future */
|
|
__u16 token_size; /* Granularity of payload */
|
|
__u16 min_tokens; /* Min acceptable token number */
|
|
__u16 max_tokens; /* Max acceptable token number */
|
|
__u32 flags; /* Special handling of the request */
|
|
};
|
|
|
|
/* Need to think of short header translation table. Later. */
|
|
|
|
/* --------------------- ENHANCED SPY 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 include this struct in its private part and use the
|
|
* standard spy iw_handler.
|
|
*/
|
|
|
|
/*
|
|
* Instance specific spy data, i.e. addresses spied and quality for them.
|
|
*/
|
|
struct iw_spy_data
|
|
{
|
|
/* --- Standard spy support --- */
|
|
int spy_number;
|
|
u_char spy_address[IW_MAX_SPY][ETH_ALEN];
|
|
struct iw_quality spy_stat[IW_MAX_SPY];
|
|
/* --- Enhanced spy support (event) */
|
|
struct iw_quality spy_thr_low; /* Low threshold */
|
|
struct iw_quality spy_thr_high; /* High threshold */
|
|
u_char spy_thr_under[IW_MAX_SPY];
|
|
};
|
|
|
|
/* --------------------- DEVICE WIRELESS DATA --------------------- */
|
|
/*
|
|
* This is all the wireless data specific to a device instance that
|
|
* is managed by the core of Wireless Extensions or the 802.11 layer.
|
|
* We only keep pointer to those structures, so that a driver is free
|
|
* to share them between instances.
|
|
* This structure should be initialised before registering the device.
|
|
* Access to this data follow the same rules as any other struct net_device
|
|
* data (i.e. valid as long as struct net_device exist, same locking rules).
|
|
*/
|
|
/* Forward declaration */
|
|
struct ieee80211_device;
|
|
/* The struct */
|
|
struct iw_public_data {
|
|
/* Driver enhanced spy support */
|
|
struct iw_spy_data * spy_data;
|
|
/* Structure managed by the in-kernel IEEE 802.11 layer */
|
|
struct ieee80211_device * ieee80211;
|
|
};
|
|
|
|
/**************************** PROTOTYPES ****************************/
|
|
/*
|
|
* Functions part of the Wireless Extensions (defined in net/core/wireless.c).
|
|
* Those may be called only within the kernel.
|
|
*/
|
|
|
|
/* functions that may be called by driver modules */
|
|
|
|
/* Send a single event to user space */
|
|
extern void wireless_send_event(struct net_device * dev,
|
|
unsigned int cmd,
|
|
union iwreq_data * wrqu,
|
|
char * extra);
|
|
|
|
/* We may need a function to send a stream of events to user space.
|
|
* More on that later... */
|
|
|
|
/* Standard handler for SIOCSIWSPY */
|
|
extern int iw_handler_set_spy(struct net_device * dev,
|
|
struct iw_request_info * info,
|
|
union iwreq_data * wrqu,
|
|
char * extra);
|
|
/* Standard handler for SIOCGIWSPY */
|
|
extern int iw_handler_get_spy(struct net_device * dev,
|
|
struct iw_request_info * info,
|
|
union iwreq_data * wrqu,
|
|
char * extra);
|
|
/* Standard handler for SIOCSIWTHRSPY */
|
|
extern int iw_handler_set_thrspy(struct net_device * dev,
|
|
struct iw_request_info *info,
|
|
union iwreq_data * wrqu,
|
|
char * extra);
|
|
/* Standard handler for SIOCGIWTHRSPY */
|
|
extern int iw_handler_get_thrspy(struct net_device * dev,
|
|
struct iw_request_info *info,
|
|
union iwreq_data * wrqu,
|
|
char * extra);
|
|
/* Driver call to update spy records */
|
|
extern void wireless_spy_update(struct net_device * dev,
|
|
unsigned char * address,
|
|
struct iw_quality * wstats);
|
|
|
|
/************************* INLINE FUNTIONS *************************/
|
|
/*
|
|
* Function that are so simple that it's more efficient inlining them
|
|
*/
|
|
|
|
/*------------------------------------------------------------------*/
|
|
/*
|
|
* Wrapper to add an Wireless Event to a stream of events.
|
|
*/
|
|
static inline char *
|
|
iwe_stream_add_event(char * stream, /* Stream of events */
|
|
char * ends, /* End of stream */
|
|
struct iw_event *iwe, /* Payload */
|
|
int event_len) /* Real size of payload */
|
|
{
|
|
/* Check if it's possible */
|
|
if(likely((stream + event_len) < ends)) {
|
|
iwe->len = event_len;
|
|
/* Beware of alignement issues on 64 bits */
|
|
memcpy(stream, (char *) iwe, IW_EV_LCP_PK_LEN);
|
|
memcpy(stream + IW_EV_LCP_LEN,
|
|
((char *) iwe) + IW_EV_LCP_LEN,
|
|
event_len - IW_EV_LCP_LEN);
|
|
stream += event_len;
|
|
}
|
|
return stream;
|
|
}
|
|
|
|
/*------------------------------------------------------------------*/
|
|
/*
|
|
* Wrapper to add an short Wireless Event containing a pointer to a
|
|
* stream of events.
|
|
*/
|
|
static inline char *
|
|
iwe_stream_add_point(char * stream, /* Stream of events */
|
|
char * ends, /* End of stream */
|
|
struct iw_event *iwe, /* Payload length + flags */
|
|
char * extra) /* More payload */
|
|
{
|
|
int event_len = IW_EV_POINT_LEN + iwe->u.data.length;
|
|
/* Check if it's possible */
|
|
if(likely((stream + event_len) < ends)) {
|
|
iwe->len = event_len;
|
|
memcpy(stream, (char *) iwe, IW_EV_LCP_PK_LEN);
|
|
memcpy(stream + IW_EV_LCP_LEN,
|
|
((char *) iwe) + IW_EV_LCP_LEN + IW_EV_POINT_OFF,
|
|
IW_EV_POINT_PK_LEN - IW_EV_LCP_PK_LEN);
|
|
memcpy(stream + IW_EV_POINT_LEN, extra, iwe->u.data.length);
|
|
stream += event_len;
|
|
}
|
|
return stream;
|
|
}
|
|
|
|
/*------------------------------------------------------------------*/
|
|
/*
|
|
* Wrapper to add a value to a Wireless Event in a stream of events.
|
|
* Be careful, this one is tricky to use properly :
|
|
* At the first run, you need to have (value = event + IW_EV_LCP_LEN).
|
|
*/
|
|
static inline char *
|
|
iwe_stream_add_value(char * event, /* Event in the stream */
|
|
char * value, /* Value in event */
|
|
char * ends, /* End of stream */
|
|
struct iw_event *iwe, /* Payload */
|
|
int event_len) /* Real size of payload */
|
|
{
|
|
/* Don't duplicate LCP */
|
|
event_len -= IW_EV_LCP_LEN;
|
|
|
|
/* Check if it's possible */
|
|
if(likely((value + event_len) < ends)) {
|
|
/* Add new value */
|
|
memcpy(value, (char *) iwe + IW_EV_LCP_LEN, event_len);
|
|
value += event_len;
|
|
/* Patch LCP */
|
|
iwe->len = value - event;
|
|
memcpy(event, (char *) iwe, IW_EV_LCP_LEN);
|
|
}
|
|
return value;
|
|
}
|
|
|
|
/*------------------------------------------------------------------*/
|
|
/*
|
|
* Wrapper to add an Wireless Event to a stream of events.
|
|
* Same as above, with explicit error check...
|
|
*/
|
|
static inline char *
|
|
iwe_stream_check_add_event(char * stream, /* Stream of events */
|
|
char * ends, /* End of stream */
|
|
struct iw_event *iwe, /* Payload */
|
|
int event_len, /* Size of payload */
|
|
int * perr) /* Error report */
|
|
{
|
|
/* Check if it's possible, set error if not */
|
|
if(likely((stream + event_len) < ends)) {
|
|
iwe->len = event_len;
|
|
/* Beware of alignement issues on 64 bits */
|
|
memcpy(stream, (char *) iwe, IW_EV_LCP_PK_LEN);
|
|
memcpy(stream + IW_EV_LCP_LEN,
|
|
((char *) iwe) + IW_EV_LCP_LEN,
|
|
event_len - IW_EV_LCP_LEN);
|
|
stream += event_len;
|
|
} else
|
|
*perr = -E2BIG;
|
|
return stream;
|
|
}
|
|
|
|
/*------------------------------------------------------------------*/
|
|
/*
|
|
* Wrapper to add an short Wireless Event containing a pointer to a
|
|
* stream of events.
|
|
* Same as above, with explicit error check...
|
|
*/
|
|
static inline char *
|
|
iwe_stream_check_add_point(char * stream, /* Stream of events */
|
|
char * ends, /* End of stream */
|
|
struct iw_event *iwe, /* Payload length + flags */
|
|
char * extra, /* More payload */
|
|
int * perr) /* Error report */
|
|
{
|
|
int event_len = IW_EV_POINT_LEN + iwe->u.data.length;
|
|
/* Check if it's possible */
|
|
if(likely((stream + event_len) < ends)) {
|
|
iwe->len = event_len;
|
|
memcpy(stream, (char *) iwe, IW_EV_LCP_PK_LEN);
|
|
memcpy(stream + IW_EV_LCP_LEN,
|
|
((char *) iwe) + IW_EV_LCP_LEN + IW_EV_POINT_OFF,
|
|
IW_EV_POINT_PK_LEN - IW_EV_LCP_PK_LEN);
|
|
memcpy(stream + IW_EV_POINT_LEN, extra, iwe->u.data.length);
|
|
stream += event_len;
|
|
} else
|
|
*perr = -E2BIG;
|
|
return stream;
|
|
}
|
|
|
|
/*------------------------------------------------------------------*/
|
|
/*
|
|
* Wrapper to add a value to a Wireless Event in a stream of events.
|
|
* Be careful, this one is tricky to use properly :
|
|
* At the first run, you need to have (value = event + IW_EV_LCP_LEN).
|
|
* Same as above, with explicit error check...
|
|
*/
|
|
static inline char *
|
|
iwe_stream_check_add_value(char * event, /* Event in the stream */
|
|
char * value, /* Value in event */
|
|
char * ends, /* End of stream */
|
|
struct iw_event *iwe, /* Payload */
|
|
int event_len, /* Size of payload */
|
|
int * perr) /* Error report */
|
|
{
|
|
/* Don't duplicate LCP */
|
|
event_len -= IW_EV_LCP_LEN;
|
|
|
|
/* Check if it's possible */
|
|
if(likely((value + event_len) < ends)) {
|
|
/* Add new value */
|
|
memcpy(value, (char *) iwe + IW_EV_LCP_LEN, event_len);
|
|
value += event_len;
|
|
/* Patch LCP */
|
|
iwe->len = value - event;
|
|
memcpy(event, (char *) iwe, IW_EV_LCP_LEN);
|
|
} else
|
|
*perr = -E2BIG;
|
|
return value;
|
|
}
|
|
|
|
#endif /* _IW_HANDLER_H */
|