alistair23-linux/net/802/garp.c
Kees Cook e99e88a9d2 treewide: setup_timer() -> timer_setup()
This converts all remaining cases of the old setup_timer() API into using
timer_setup(), where the callback argument is the structure already
holding the struct timer_list. These should have no behavioral changes,
since they just change which pointer is passed into the callback with
the same available pointers after conversion. It handles the following
examples, in addition to some other variations.

Casting from unsigned long:

    void my_callback(unsigned long data)
    {
        struct something *ptr = (struct something *)data;
    ...
    }
    ...
    setup_timer(&ptr->my_timer, my_callback, ptr);

and forced object casts:

    void my_callback(struct something *ptr)
    {
    ...
    }
    ...
    setup_timer(&ptr->my_timer, my_callback, (unsigned long)ptr);

become:

    void my_callback(struct timer_list *t)
    {
        struct something *ptr = from_timer(ptr, t, my_timer);
    ...
    }
    ...
    timer_setup(&ptr->my_timer, my_callback, 0);

Direct function assignments:

    void my_callback(unsigned long data)
    {
        struct something *ptr = (struct something *)data;
    ...
    }
    ...
    ptr->my_timer.function = my_callback;

have a temporary cast added, along with converting the args:

    void my_callback(struct timer_list *t)
    {
        struct something *ptr = from_timer(ptr, t, my_timer);
    ...
    }
    ...
    ptr->my_timer.function = (TIMER_FUNC_TYPE)my_callback;

And finally, callbacks without a data assignment:

    void my_callback(unsigned long data)
    {
    ...
    }
    ...
    setup_timer(&ptr->my_timer, my_callback, 0);

have their argument renamed to verify they're unused during conversion:

    void my_callback(struct timer_list *unused)
    {
    ...
    }
    ...
    timer_setup(&ptr->my_timer, my_callback, 0);

The conversion is done with the following Coccinelle script:

spatch --very-quiet --all-includes --include-headers \
	-I ./arch/x86/include -I ./arch/x86/include/generated \
	-I ./include -I ./arch/x86/include/uapi \
	-I ./arch/x86/include/generated/uapi -I ./include/uapi \
	-I ./include/generated/uapi --include ./include/linux/kconfig.h \
	--dir . \
	--cocci-file ~/src/data/timer_setup.cocci

@fix_address_of@
expression e;
@@

 setup_timer(
-&(e)
+&e
 , ...)

// Update any raw setup_timer() usages that have a NULL callback, but
// would otherwise match change_timer_function_usage, since the latter
// will update all function assignments done in the face of a NULL
// function initialization in setup_timer().
@change_timer_function_usage_NULL@
expression _E;
identifier _timer;
type _cast_data;
@@

(
-setup_timer(&_E->_timer, NULL, _E);
+timer_setup(&_E->_timer, NULL, 0);
|
-setup_timer(&_E->_timer, NULL, (_cast_data)_E);
+timer_setup(&_E->_timer, NULL, 0);
|
-setup_timer(&_E._timer, NULL, &_E);
+timer_setup(&_E._timer, NULL, 0);
|
-setup_timer(&_E._timer, NULL, (_cast_data)&_E);
+timer_setup(&_E._timer, NULL, 0);
)

@change_timer_function_usage@
expression _E;
identifier _timer;
struct timer_list _stl;
identifier _callback;
type _cast_func, _cast_data;
@@

(
-setup_timer(&_E->_timer, _callback, _E);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E->_timer, &_callback, _E);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E->_timer, _callback, (_cast_data)_E);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E->_timer, &_callback, (_cast_data)_E);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E->_timer, (_cast_func)_callback, _E);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E->_timer, (_cast_func)&_callback, _E);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E->_timer, (_cast_func)_callback, (_cast_data)_E);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E->_timer, (_cast_func)&_callback, (_cast_data)_E);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E._timer, _callback, (_cast_data)_E);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_E._timer, _callback, (_cast_data)&_E);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_E._timer, &_callback, (_cast_data)_E);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_E._timer, &_callback, (_cast_data)&_E);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_E._timer, (_cast_func)_callback, (_cast_data)_E);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_E._timer, (_cast_func)_callback, (_cast_data)&_E);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_E._timer, (_cast_func)&_callback, (_cast_data)_E);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_E._timer, (_cast_func)&_callback, (_cast_data)&_E);
+timer_setup(&_E._timer, _callback, 0);
|
 _E->_timer@_stl.function = _callback;
|
 _E->_timer@_stl.function = &_callback;
|
 _E->_timer@_stl.function = (_cast_func)_callback;
|
 _E->_timer@_stl.function = (_cast_func)&_callback;
|
 _E._timer@_stl.function = _callback;
|
 _E._timer@_stl.function = &_callback;
|
 _E._timer@_stl.function = (_cast_func)_callback;
|
 _E._timer@_stl.function = (_cast_func)&_callback;
)

// callback(unsigned long arg)
@change_callback_handle_cast
 depends on change_timer_function_usage@
identifier change_timer_function_usage._callback;
identifier change_timer_function_usage._timer;
type _origtype;
identifier _origarg;
type _handletype;
identifier _handle;
@@

 void _callback(
-_origtype _origarg
+struct timer_list *t
 )
 {
(
	... when != _origarg
	_handletype *_handle =
-(_handletype *)_origarg;
+from_timer(_handle, t, _timer);
	... when != _origarg
|
	... when != _origarg
	_handletype *_handle =
-(void *)_origarg;
+from_timer(_handle, t, _timer);
	... when != _origarg
|
	... when != _origarg
	_handletype *_handle;
	... when != _handle
	_handle =
-(_handletype *)_origarg;
+from_timer(_handle, t, _timer);
	... when != _origarg
|
	... when != _origarg
	_handletype *_handle;
	... when != _handle
	_handle =
-(void *)_origarg;
+from_timer(_handle, t, _timer);
	... when != _origarg
)
 }

// callback(unsigned long arg) without existing variable
@change_callback_handle_cast_no_arg
 depends on change_timer_function_usage &&
                     !change_callback_handle_cast@
identifier change_timer_function_usage._callback;
identifier change_timer_function_usage._timer;
type _origtype;
identifier _origarg;
type _handletype;
@@

 void _callback(
-_origtype _origarg
+struct timer_list *t
 )
 {
+	_handletype *_origarg = from_timer(_origarg, t, _timer);
+
	... when != _origarg
-	(_handletype *)_origarg
+	_origarg
	... when != _origarg
 }

// Avoid already converted callbacks.
@match_callback_converted
 depends on change_timer_function_usage &&
            !change_callback_handle_cast &&
	    !change_callback_handle_cast_no_arg@
identifier change_timer_function_usage._callback;
identifier t;
@@

 void _callback(struct timer_list *t)
 { ... }

// callback(struct something *handle)
@change_callback_handle_arg
 depends on change_timer_function_usage &&
	    !match_callback_converted &&
            !change_callback_handle_cast &&
            !change_callback_handle_cast_no_arg@
identifier change_timer_function_usage._callback;
identifier change_timer_function_usage._timer;
type _handletype;
identifier _handle;
@@

 void _callback(
-_handletype *_handle
+struct timer_list *t
 )
 {
+	_handletype *_handle = from_timer(_handle, t, _timer);
	...
 }

// If change_callback_handle_arg ran on an empty function, remove
// the added handler.
@unchange_callback_handle_arg
 depends on change_timer_function_usage &&
	    change_callback_handle_arg@
identifier change_timer_function_usage._callback;
identifier change_timer_function_usage._timer;
type _handletype;
identifier _handle;
identifier t;
@@

 void _callback(struct timer_list *t)
 {
-	_handletype *_handle = from_timer(_handle, t, _timer);
 }

// We only want to refactor the setup_timer() data argument if we've found
// the matching callback. This undoes changes in change_timer_function_usage.
@unchange_timer_function_usage
 depends on change_timer_function_usage &&
            !change_callback_handle_cast &&
            !change_callback_handle_cast_no_arg &&
	    !change_callback_handle_arg@
expression change_timer_function_usage._E;
identifier change_timer_function_usage._timer;
identifier change_timer_function_usage._callback;
type change_timer_function_usage._cast_data;
@@

(
-timer_setup(&_E->_timer, _callback, 0);
+setup_timer(&_E->_timer, _callback, (_cast_data)_E);
|
-timer_setup(&_E._timer, _callback, 0);
+setup_timer(&_E._timer, _callback, (_cast_data)&_E);
)

// If we fixed a callback from a .function assignment, fix the
// assignment cast now.
@change_timer_function_assignment
 depends on change_timer_function_usage &&
            (change_callback_handle_cast ||
             change_callback_handle_cast_no_arg ||
             change_callback_handle_arg)@
expression change_timer_function_usage._E;
identifier change_timer_function_usage._timer;
identifier change_timer_function_usage._callback;
type _cast_func;
typedef TIMER_FUNC_TYPE;
@@

(
 _E->_timer.function =
-_callback
+(TIMER_FUNC_TYPE)_callback
 ;
|
 _E->_timer.function =
-&_callback
+(TIMER_FUNC_TYPE)_callback
 ;
|
 _E->_timer.function =
-(_cast_func)_callback;
+(TIMER_FUNC_TYPE)_callback
 ;
|
 _E->_timer.function =
-(_cast_func)&_callback
+(TIMER_FUNC_TYPE)_callback
 ;
|
 _E._timer.function =
-_callback
+(TIMER_FUNC_TYPE)_callback
 ;
|
 _E._timer.function =
-&_callback;
+(TIMER_FUNC_TYPE)_callback
 ;
|
 _E._timer.function =
-(_cast_func)_callback
+(TIMER_FUNC_TYPE)_callback
 ;
|
 _E._timer.function =
-(_cast_func)&_callback
+(TIMER_FUNC_TYPE)_callback
 ;
)

// Sometimes timer functions are called directly. Replace matched args.
@change_timer_function_calls
 depends on change_timer_function_usage &&
            (change_callback_handle_cast ||
             change_callback_handle_cast_no_arg ||
             change_callback_handle_arg)@
expression _E;
identifier change_timer_function_usage._timer;
identifier change_timer_function_usage._callback;
type _cast_data;
@@

 _callback(
(
-(_cast_data)_E
+&_E->_timer
|
-(_cast_data)&_E
+&_E._timer
|
-_E
+&_E->_timer
)
 )

// If a timer has been configured without a data argument, it can be
// converted without regard to the callback argument, since it is unused.
@match_timer_function_unused_data@
expression _E;
identifier _timer;
identifier _callback;
@@

(
-setup_timer(&_E->_timer, _callback, 0);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E->_timer, _callback, 0L);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E->_timer, _callback, 0UL);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E._timer, _callback, 0);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_E._timer, _callback, 0L);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_E._timer, _callback, 0UL);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_timer, _callback, 0);
+timer_setup(&_timer, _callback, 0);
|
-setup_timer(&_timer, _callback, 0L);
+timer_setup(&_timer, _callback, 0);
|
-setup_timer(&_timer, _callback, 0UL);
+timer_setup(&_timer, _callback, 0);
|
-setup_timer(_timer, _callback, 0);
+timer_setup(_timer, _callback, 0);
|
-setup_timer(_timer, _callback, 0L);
+timer_setup(_timer, _callback, 0);
|
-setup_timer(_timer, _callback, 0UL);
+timer_setup(_timer, _callback, 0);
)

@change_callback_unused_data
 depends on match_timer_function_unused_data@
identifier match_timer_function_unused_data._callback;
type _origtype;
identifier _origarg;
@@

 void _callback(
-_origtype _origarg
+struct timer_list *unused
 )
 {
	... when != _origarg
 }

Signed-off-by: Kees Cook <keescook@chromium.org>
2017-11-21 15:57:07 -08:00

639 lines
18 KiB
C

/*
* IEEE 802.1D Generic Attribute Registration Protocol (GARP)
*
* Copyright (c) 2008 Patrick McHardy <kaber@trash.net>
*
* 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.
*/
#include <linux/kernel.h>
#include <linux/timer.h>
#include <linux/skbuff.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/rtnetlink.h>
#include <linux/llc.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <net/llc.h>
#include <net/llc_pdu.h>
#include <net/garp.h>
#include <asm/unaligned.h>
static unsigned int garp_join_time __read_mostly = 200;
module_param(garp_join_time, uint, 0644);
MODULE_PARM_DESC(garp_join_time, "Join time in ms (default 200ms)");
MODULE_LICENSE("GPL");
static const struct garp_state_trans {
u8 state;
u8 action;
} garp_applicant_state_table[GARP_APPLICANT_MAX + 1][GARP_EVENT_MAX + 1] = {
[GARP_APPLICANT_VA] = {
[GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_AA,
.action = GARP_ACTION_S_JOIN_IN },
[GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_AA },
[GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VA },
[GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VA },
[GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VA },
[GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VP },
[GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_INVALID },
[GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_LA },
},
[GARP_APPLICANT_AA] = {
[GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_QA,
.action = GARP_ACTION_S_JOIN_IN },
[GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_QA },
[GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VA },
[GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VA },
[GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VA },
[GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VP },
[GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_INVALID },
[GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_LA },
},
[GARP_APPLICANT_QA] = {
[GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_INVALID },
[GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_QA },
[GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VA },
[GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VA },
[GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VP },
[GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VP },
[GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_INVALID },
[GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_LA },
},
[GARP_APPLICANT_LA] = {
[GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_VO,
.action = GARP_ACTION_S_LEAVE_EMPTY },
[GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_LA },
[GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VO },
[GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_LA },
[GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_LA },
[GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VO },
[GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_VA },
[GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_INVALID },
},
[GARP_APPLICANT_VP] = {
[GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_AA,
.action = GARP_ACTION_S_JOIN_IN },
[GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_AP },
[GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VP },
[GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VP },
[GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VP },
[GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VP },
[GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_INVALID },
[GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_VO },
},
[GARP_APPLICANT_AP] = {
[GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_QA,
.action = GARP_ACTION_S_JOIN_IN },
[GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_QP },
[GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VP },
[GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VP },
[GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VP },
[GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VP },
[GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_INVALID },
[GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_AO },
},
[GARP_APPLICANT_QP] = {
[GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_INVALID },
[GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_QP },
[GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VP },
[GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VP },
[GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VP },
[GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VP },
[GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_INVALID },
[GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_QO },
},
[GARP_APPLICANT_VO] = {
[GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_INVALID },
[GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_AO },
[GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VO },
[GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VO },
[GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VO },
[GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VO },
[GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_VP },
[GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_INVALID },
},
[GARP_APPLICANT_AO] = {
[GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_INVALID },
[GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_QO },
[GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VO },
[GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VO },
[GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VO },
[GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VO },
[GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_AP },
[GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_INVALID },
},
[GARP_APPLICANT_QO] = {
[GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_INVALID },
[GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_QO },
[GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VO },
[GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VO },
[GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VO },
[GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VO },
[GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_QP },
[GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_INVALID },
},
};
static int garp_attr_cmp(const struct garp_attr *attr,
const void *data, u8 len, u8 type)
{
if (attr->type != type)
return attr->type - type;
if (attr->dlen != len)
return attr->dlen - len;
return memcmp(attr->data, data, len);
}
static struct garp_attr *garp_attr_lookup(const struct garp_applicant *app,
const void *data, u8 len, u8 type)
{
struct rb_node *parent = app->gid.rb_node;
struct garp_attr *attr;
int d;
while (parent) {
attr = rb_entry(parent, struct garp_attr, node);
d = garp_attr_cmp(attr, data, len, type);
if (d > 0)
parent = parent->rb_left;
else if (d < 0)
parent = parent->rb_right;
else
return attr;
}
return NULL;
}
static struct garp_attr *garp_attr_create(struct garp_applicant *app,
const void *data, u8 len, u8 type)
{
struct rb_node *parent = NULL, **p = &app->gid.rb_node;
struct garp_attr *attr;
int d;
while (*p) {
parent = *p;
attr = rb_entry(parent, struct garp_attr, node);
d = garp_attr_cmp(attr, data, len, type);
if (d > 0)
p = &parent->rb_left;
else if (d < 0)
p = &parent->rb_right;
else {
/* The attribute already exists; re-use it. */
return attr;
}
}
attr = kmalloc(sizeof(*attr) + len, GFP_ATOMIC);
if (!attr)
return attr;
attr->state = GARP_APPLICANT_VO;
attr->type = type;
attr->dlen = len;
memcpy(attr->data, data, len);
rb_link_node(&attr->node, parent, p);
rb_insert_color(&attr->node, &app->gid);
return attr;
}
static void garp_attr_destroy(struct garp_applicant *app, struct garp_attr *attr)
{
rb_erase(&attr->node, &app->gid);
kfree(attr);
}
static int garp_pdu_init(struct garp_applicant *app)
{
struct sk_buff *skb;
struct garp_pdu_hdr *gp;
#define LLC_RESERVE sizeof(struct llc_pdu_un)
skb = alloc_skb(app->dev->mtu + LL_RESERVED_SPACE(app->dev),
GFP_ATOMIC);
if (!skb)
return -ENOMEM;
skb->dev = app->dev;
skb->protocol = htons(ETH_P_802_2);
skb_reserve(skb, LL_RESERVED_SPACE(app->dev) + LLC_RESERVE);
gp = __skb_put(skb, sizeof(*gp));
put_unaligned(htons(GARP_PROTOCOL_ID), &gp->protocol);
app->pdu = skb;
return 0;
}
static int garp_pdu_append_end_mark(struct garp_applicant *app)
{
if (skb_tailroom(app->pdu) < sizeof(u8))
return -1;
__skb_put_u8(app->pdu, GARP_END_MARK);
return 0;
}
static void garp_pdu_queue(struct garp_applicant *app)
{
if (!app->pdu)
return;
garp_pdu_append_end_mark(app);
garp_pdu_append_end_mark(app);
llc_pdu_header_init(app->pdu, LLC_PDU_TYPE_U, LLC_SAP_BSPAN,
LLC_SAP_BSPAN, LLC_PDU_CMD);
llc_pdu_init_as_ui_cmd(app->pdu);
llc_mac_hdr_init(app->pdu, app->dev->dev_addr,
app->app->proto.group_address);
skb_queue_tail(&app->queue, app->pdu);
app->pdu = NULL;
}
static void garp_queue_xmit(struct garp_applicant *app)
{
struct sk_buff *skb;
while ((skb = skb_dequeue(&app->queue)))
dev_queue_xmit(skb);
}
static int garp_pdu_append_msg(struct garp_applicant *app, u8 attrtype)
{
struct garp_msg_hdr *gm;
if (skb_tailroom(app->pdu) < sizeof(*gm))
return -1;
gm = __skb_put(app->pdu, sizeof(*gm));
gm->attrtype = attrtype;
garp_cb(app->pdu)->cur_type = attrtype;
return 0;
}
static int garp_pdu_append_attr(struct garp_applicant *app,
const struct garp_attr *attr,
enum garp_attr_event event)
{
struct garp_attr_hdr *ga;
unsigned int len;
int err;
again:
if (!app->pdu) {
err = garp_pdu_init(app);
if (err < 0)
return err;
}
if (garp_cb(app->pdu)->cur_type != attr->type) {
if (garp_cb(app->pdu)->cur_type &&
garp_pdu_append_end_mark(app) < 0)
goto queue;
if (garp_pdu_append_msg(app, attr->type) < 0)
goto queue;
}
len = sizeof(*ga) + attr->dlen;
if (skb_tailroom(app->pdu) < len)
goto queue;
ga = __skb_put(app->pdu, len);
ga->len = len;
ga->event = event;
memcpy(ga->data, attr->data, attr->dlen);
return 0;
queue:
garp_pdu_queue(app);
goto again;
}
static void garp_attr_event(struct garp_applicant *app,
struct garp_attr *attr, enum garp_event event)
{
enum garp_applicant_state state;
state = garp_applicant_state_table[attr->state][event].state;
if (state == GARP_APPLICANT_INVALID)
return;
switch (garp_applicant_state_table[attr->state][event].action) {
case GARP_ACTION_NONE:
break;
case GARP_ACTION_S_JOIN_IN:
/* When appending the attribute fails, don't update state in
* order to retry on next TRANSMIT_PDU event. */
if (garp_pdu_append_attr(app, attr, GARP_JOIN_IN) < 0)
return;
break;
case GARP_ACTION_S_LEAVE_EMPTY:
garp_pdu_append_attr(app, attr, GARP_LEAVE_EMPTY);
/* As a pure applicant, sending a leave message implies that
* the attribute was unregistered and can be destroyed. */
garp_attr_destroy(app, attr);
return;
default:
WARN_ON(1);
}
attr->state = state;
}
int garp_request_join(const struct net_device *dev,
const struct garp_application *appl,
const void *data, u8 len, u8 type)
{
struct garp_port *port = rtnl_dereference(dev->garp_port);
struct garp_applicant *app = rtnl_dereference(port->applicants[appl->type]);
struct garp_attr *attr;
spin_lock_bh(&app->lock);
attr = garp_attr_create(app, data, len, type);
if (!attr) {
spin_unlock_bh(&app->lock);
return -ENOMEM;
}
garp_attr_event(app, attr, GARP_EVENT_REQ_JOIN);
spin_unlock_bh(&app->lock);
return 0;
}
EXPORT_SYMBOL_GPL(garp_request_join);
void garp_request_leave(const struct net_device *dev,
const struct garp_application *appl,
const void *data, u8 len, u8 type)
{
struct garp_port *port = rtnl_dereference(dev->garp_port);
struct garp_applicant *app = rtnl_dereference(port->applicants[appl->type]);
struct garp_attr *attr;
spin_lock_bh(&app->lock);
attr = garp_attr_lookup(app, data, len, type);
if (!attr) {
spin_unlock_bh(&app->lock);
return;
}
garp_attr_event(app, attr, GARP_EVENT_REQ_LEAVE);
spin_unlock_bh(&app->lock);
}
EXPORT_SYMBOL_GPL(garp_request_leave);
static void garp_gid_event(struct garp_applicant *app, enum garp_event event)
{
struct rb_node *node, *next;
struct garp_attr *attr;
for (node = rb_first(&app->gid);
next = node ? rb_next(node) : NULL, node != NULL;
node = next) {
attr = rb_entry(node, struct garp_attr, node);
garp_attr_event(app, attr, event);
}
}
static void garp_join_timer_arm(struct garp_applicant *app)
{
unsigned long delay;
delay = (u64)msecs_to_jiffies(garp_join_time) * prandom_u32() >> 32;
mod_timer(&app->join_timer, jiffies + delay);
}
static void garp_join_timer(struct timer_list *t)
{
struct garp_applicant *app = from_timer(app, t, join_timer);
spin_lock(&app->lock);
garp_gid_event(app, GARP_EVENT_TRANSMIT_PDU);
garp_pdu_queue(app);
spin_unlock(&app->lock);
garp_queue_xmit(app);
garp_join_timer_arm(app);
}
static int garp_pdu_parse_end_mark(struct sk_buff *skb)
{
if (!pskb_may_pull(skb, sizeof(u8)))
return -1;
if (*skb->data == GARP_END_MARK) {
skb_pull(skb, sizeof(u8));
return -1;
}
return 0;
}
static int garp_pdu_parse_attr(struct garp_applicant *app, struct sk_buff *skb,
u8 attrtype)
{
const struct garp_attr_hdr *ga;
struct garp_attr *attr;
enum garp_event event;
unsigned int dlen;
if (!pskb_may_pull(skb, sizeof(*ga)))
return -1;
ga = (struct garp_attr_hdr *)skb->data;
if (ga->len < sizeof(*ga))
return -1;
if (!pskb_may_pull(skb, ga->len))
return -1;
skb_pull(skb, ga->len);
dlen = sizeof(*ga) - ga->len;
if (attrtype > app->app->maxattr)
return 0;
switch (ga->event) {
case GARP_LEAVE_ALL:
if (dlen != 0)
return -1;
garp_gid_event(app, GARP_EVENT_R_LEAVE_EMPTY);
return 0;
case GARP_JOIN_EMPTY:
event = GARP_EVENT_R_JOIN_EMPTY;
break;
case GARP_JOIN_IN:
event = GARP_EVENT_R_JOIN_IN;
break;
case GARP_LEAVE_EMPTY:
event = GARP_EVENT_R_LEAVE_EMPTY;
break;
case GARP_EMPTY:
event = GARP_EVENT_R_EMPTY;
break;
default:
return 0;
}
if (dlen == 0)
return -1;
attr = garp_attr_lookup(app, ga->data, dlen, attrtype);
if (attr == NULL)
return 0;
garp_attr_event(app, attr, event);
return 0;
}
static int garp_pdu_parse_msg(struct garp_applicant *app, struct sk_buff *skb)
{
const struct garp_msg_hdr *gm;
if (!pskb_may_pull(skb, sizeof(*gm)))
return -1;
gm = (struct garp_msg_hdr *)skb->data;
if (gm->attrtype == 0)
return -1;
skb_pull(skb, sizeof(*gm));
while (skb->len > 0) {
if (garp_pdu_parse_attr(app, skb, gm->attrtype) < 0)
return -1;
if (garp_pdu_parse_end_mark(skb) < 0)
break;
}
return 0;
}
static void garp_pdu_rcv(const struct stp_proto *proto, struct sk_buff *skb,
struct net_device *dev)
{
struct garp_application *appl = proto->data;
struct garp_port *port;
struct garp_applicant *app;
const struct garp_pdu_hdr *gp;
port = rcu_dereference(dev->garp_port);
if (!port)
goto err;
app = rcu_dereference(port->applicants[appl->type]);
if (!app)
goto err;
if (!pskb_may_pull(skb, sizeof(*gp)))
goto err;
gp = (struct garp_pdu_hdr *)skb->data;
if (get_unaligned(&gp->protocol) != htons(GARP_PROTOCOL_ID))
goto err;
skb_pull(skb, sizeof(*gp));
spin_lock(&app->lock);
while (skb->len > 0) {
if (garp_pdu_parse_msg(app, skb) < 0)
break;
if (garp_pdu_parse_end_mark(skb) < 0)
break;
}
spin_unlock(&app->lock);
err:
kfree_skb(skb);
}
static int garp_init_port(struct net_device *dev)
{
struct garp_port *port;
port = kzalloc(sizeof(*port), GFP_KERNEL);
if (!port)
return -ENOMEM;
rcu_assign_pointer(dev->garp_port, port);
return 0;
}
static void garp_release_port(struct net_device *dev)
{
struct garp_port *port = rtnl_dereference(dev->garp_port);
unsigned int i;
for (i = 0; i <= GARP_APPLICATION_MAX; i++) {
if (rtnl_dereference(port->applicants[i]))
return;
}
RCU_INIT_POINTER(dev->garp_port, NULL);
kfree_rcu(port, rcu);
}
int garp_init_applicant(struct net_device *dev, struct garp_application *appl)
{
struct garp_applicant *app;
int err;
ASSERT_RTNL();
if (!rtnl_dereference(dev->garp_port)) {
err = garp_init_port(dev);
if (err < 0)
goto err1;
}
err = -ENOMEM;
app = kzalloc(sizeof(*app), GFP_KERNEL);
if (!app)
goto err2;
err = dev_mc_add(dev, appl->proto.group_address);
if (err < 0)
goto err3;
app->dev = dev;
app->app = appl;
app->gid = RB_ROOT;
spin_lock_init(&app->lock);
skb_queue_head_init(&app->queue);
rcu_assign_pointer(dev->garp_port->applicants[appl->type], app);
timer_setup(&app->join_timer, garp_join_timer, 0);
garp_join_timer_arm(app);
return 0;
err3:
kfree(app);
err2:
garp_release_port(dev);
err1:
return err;
}
EXPORT_SYMBOL_GPL(garp_init_applicant);
void garp_uninit_applicant(struct net_device *dev, struct garp_application *appl)
{
struct garp_port *port = rtnl_dereference(dev->garp_port);
struct garp_applicant *app = rtnl_dereference(port->applicants[appl->type]);
ASSERT_RTNL();
RCU_INIT_POINTER(port->applicants[appl->type], NULL);
/* Delete timer and generate a final TRANSMIT_PDU event to flush out
* all pending messages before the applicant is gone. */
del_timer_sync(&app->join_timer);
spin_lock_bh(&app->lock);
garp_gid_event(app, GARP_EVENT_TRANSMIT_PDU);
garp_pdu_queue(app);
spin_unlock_bh(&app->lock);
garp_queue_xmit(app);
dev_mc_del(dev, appl->proto.group_address);
kfree_rcu(app, rcu);
garp_release_port(dev);
}
EXPORT_SYMBOL_GPL(garp_uninit_applicant);
int garp_register_application(struct garp_application *appl)
{
appl->proto.rcv = garp_pdu_rcv;
appl->proto.data = appl;
return stp_proto_register(&appl->proto);
}
EXPORT_SYMBOL_GPL(garp_register_application);
void garp_unregister_application(struct garp_application *appl)
{
stp_proto_unregister(&appl->proto);
}
EXPORT_SYMBOL_GPL(garp_unregister_application);