Commit Graph

51616 Commits

Author SHA1 Message Date
Arnaldo Carvalho de Melo
dc5fc579b9 [NETLINK]: Use nlmsg_trim() where appropriate
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:26:37 -07:00
Arnaldo Carvalho de Melo
a36ca73337 [NETLINK]: Remove NLMSG_{NEW_ANSWER,CANCEL,END}
Not used anywhere and defined inside __KERNEL__, Thomas acked this on irc.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2007-04-25 22:26:36 -07:00
Arnaldo Carvalho de Melo
897933bcdf [SK_BUFF]: Remove skb_add_mtu() leftovers
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2007-04-25 22:26:35 -07:00
Arnaldo Carvalho de Melo
b529ccf279 [NETLINK]: Introduce nlmsg_hdr() helper
For the common "(struct nlmsghdr *)skb->data" sequence, so that we reduce the
number of direct accesses to skb->data and for consistency with all the other
cast skb member helpers.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:26:34 -07:00
Robert Olsson
965ffea43d [IPV4]: fib_trie root node settings
The threshold for root node can be more aggressive set to get
better tree compression. The new setting mekes the root grow
from 16 to 19 bits and substansial improvemnt in Aver depth
this with the current table of 214393 prefixes

But really the dynamic resize should need more investigation
both in terms convergence and performance and maybe it should
be possible to change...

Maybe just for the brave to start with or we may have to back
this out.
2007-04-25 22:26:32 -07:00
Robert Olsson
05eee48c5a [IPV4]: fib_trie resize break
The patch below adds break condition for the resize operations. If
we don't achieve the desired fill factor a warning is printed. Trie
should still be operational but new thresholds should be considered.

Signed-off-by: Robert Olsson <robert.olsson@its.uu.se>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:26:32 -07:00
Arnaldo Carvalho de Melo
ca0605a7c8 [SK_BUFF]: Adjust the zeroing up to tail in __alloc_skb too
I did it just in alloc_skb_from_cache, forgot __alloc_skb, fixed now.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:26:31 -07:00
Arnaldo Carvalho de Melo
4305b54135 [SK_BUFF]: Convert skb->end to sk_buff_data_t
Now to convert the last one, skb->data, that will allow many simplifications
and removal of some of the offset helpers.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:26:29 -07:00
Arnaldo Carvalho de Melo
27a884dc3c [SK_BUFF]: Convert skb->tail to sk_buff_data_t
So that it is also an offset from skb->head, reduces its size from 8 to 4 bytes
on 64bit architectures, allowing us to combine the 4 bytes hole left by the
layer headers conversion, reducing struct sk_buff size to 256 bytes, i.e. 4
64byte cachelines, and since the sk_buff slab cache is SLAB_HWCACHE_ALIGN...
:-)

Many calculations that previously required that skb->{transport,network,
mac}_header be first converted to a pointer now can be done directly, being
meaningful as offsets or pointers.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:26:28 -07:00
David S. Miller
be8bd86321 [VLAN] vlan_dev: Use skb_reset_network_header().
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:26:26 -07:00
Peter Kovar
afdf27c956 [IrDA]: SMC SuperIO Chip LPC47N227 not identified properly
SMC SuperIO Chip LPC47N227 used for IrDA is not detected because its device
identification byte can be 0x7A instead of 0x5A.

Patch from Peter Kovar <peter.kovar@gmail.com>
Cc: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Samuel Ortiz <samuel@sortiz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:26:25 -07:00
Samuel Ortiz
c7630a4b93 [IrDA]: irda lockdep annotation
Rmmoding irda triggers a lockdep false positive.

Reported-by: Dave Jones <davej@redhat.com>
Signed-off-by: Samuel Ortiz <samuel@sortiz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:26:23 -07:00
Samuel Ortiz
5c81cd75fa [IrDA]: removing stir4200 useless include
stir4200 doesn't need to include irlap.h

Signed-off-by: Samuel Ortiz <samuel@sortiz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:26:22 -07:00
Arnaldo Carvalho de Melo
2e07fa9cd3 [SK_BUFF]: Use offsets for skb->{mac,network,transport}_header on 64bit architectures
With this we save 8 bytes per network packet, leaving a 4 bytes hole to be used
in further shrinking work, likely with the offsetization of other pointers,
such as ->{data,tail,end}, at the cost of adds, that were minimized by the
usual practice of setting skb->{mac,nh,n}.raw to a local variable that is then
accessed multiple times in each function, it also is not more expensive than
before with regards to most of the handling of such headers, like setting one
of these headers to another (transport to network, etc), or subtracting, adding
to/from it, comparing them, etc.

Now we have this layout for sk_buff on a x86_64 machine:

[acme@mica net-2.6.22]$ pahole vmlinux sk_buff
struct sk_buff {
	struct sk_buff *       next;             /*   0   8 */
	struct sk_buff *       prev;             /*   8   8 */
	struct rb_node         rb;               /*  16  24 */
	struct sock *          sk;               /*  40   8 */
	ktime_t                tstamp;           /*  48   8 */
	struct net_device *    dev;              /*  56   8 */
	/* --- cacheline 1 boundary (64 bytes) --- */
	struct net_device *    input_dev;        /*  64   8 */
	sk_buff_data_t         transport_header; /*  72   4 */
	sk_buff_data_t         network_header;   /*  76   4 */
	sk_buff_data_t         mac_header;       /*  80   4 */

	/* XXX 4 bytes hole, try to pack */

	struct dst_entry *     dst;              /*  88   8 */
	struct sec_path *      sp;               /*  96   8 */
	char                   cb[48];           /* 104  48 */
	/* cacheline 2 boundary (128 bytes) was 24 bytes ago*/
	unsigned int           len;              /* 152   4 */
	unsigned int           data_len;         /* 156   4 */
	unsigned int           mac_len;          /* 160   4 */
	union {
		__wsum         csum;             /*       4 */
		__u32          csum_offset;      /*       4 */
	};                                       /* 164   4 */
	__u32                  priority;         /* 168   4 */
	__u8                   local_df:1;       /* 172   1 */
	__u8                   cloned:1;         /* 172   1 */
	__u8                   ip_summed:2;      /* 172   1 */
	__u8                   nohdr:1;          /* 172   1 */
	__u8                   nfctinfo:3;       /* 172   1 */
	__u8                   pkt_type:3;       /* 173   1 */
	__u8                   fclone:2;         /* 173   1 */
	__u8                   ipvs_property:1;  /* 173   1 */

	/* XXX 2 bits hole, try to pack */

	__be16                 protocol;         /* 174   2 */
	void    (*destructor)(struct sk_buff *); /* 176   8 */
	struct nf_conntrack *  nfct;             /* 184   8 */
	/* --- cacheline 3 boundary (192 bytes) --- */
	struct sk_buff *       nfct_reasm;       /* 192   8 */
	struct nf_bridge_info *nf_bridge;        /* 200   8 */
	__u16                  tc_index;         /* 208   2 */
	__u16                  tc_verd;          /* 210   2 */
	dma_cookie_t           dma_cookie;       /* 212   4 */
	__u32                  secmark;          /* 216   4 */
	__u32                  mark;             /* 220   4 */
	unsigned int           truesize;         /* 224   4 */
	atomic_t               users;            /* 228   4 */
	unsigned char *        head;             /* 232   8 */
	unsigned char *        data;             /* 240   8 */
	unsigned char *        tail;             /* 248   8 */
	/* --- cacheline 4 boundary (256 bytes) --- */
	unsigned char *        end;              /* 256   8 */
}; /* size: 264, cachelines: 5 */
   /* sum members: 260, holes: 1, sum holes: 4 */
   /* bit holes: 1, sum bit holes: 2 bits */
   /* last cacheline: 8 bytes */

On 32 bits nothing changes, and pointers continue to be used with the compiler
turning all this abstraction layer into dust. But there are some sk_buff
validation tricks that are now possible, humm... :-)

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:26:21 -07:00
Arnaldo Carvalho de Melo
b0e380b1d8 [SK_BUFF]: unions of just one member don't get anything done, kill them
Renaming skb->h to skb->transport_header, skb->nh to skb->network_header and
skb->mac to skb->mac_header, to match the names of the associated helpers
(skb[_[re]set]_{transport,network,mac}_header).

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:26:20 -07:00
Arnaldo Carvalho de Melo
cfe1fc7759 [SK_BUFF]: Introduce skb_network_header_len
For the common sequence "skb->h.raw - skb->nh.raw", similar to skb->mac_len,
that is precalculated tho, don't think we need to bloat skb with one more
member, so just use this new helper, reducing the number of non-skbuff.h
references to the layer headers even more.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:26:19 -07:00
Arnaldo Carvalho de Melo
bff9b61ce3 [SK_BUFF]: Use the helpers to get the layer header pointer
Some more cases...

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:26:18 -07:00
Patrick McHardy
514bca322c [NET_SCHED]: Fix warning
net/sched/sch_api.c: In function 'psched_show':
net/sched/sch_api.c:1219: warning: format '%08x' expects type 'unsigned int', but argument 6 has type 's64'

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:26:17 -07:00
Patrick McHardy
bb239acf56 [NET_SCHED]: sch_cbq: fix watchdog scheduled too late
q->now is increased during dequeue and doesn't contain the current time
afterwards, resulting in a too large timeout value for the qdisc watchdog.
Use "now" instead, which still contains the current time.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:26:16 -07:00
Patrick McHardy
4361cb17f0 [NET_SCHED]: Export real timer resolution in /proc/net/psched
The timer resolution exported in /proc/net/psched is used by userspace to
calculate HTB's burst values. Currently it is set to HZ, since we're now
using hrtimers, use KTIME_MONOTONIC_RES, which makes HTB use smaller burst
values.

This patch also affects libnl, which incorrectly uses this value for
the SFQ perturbation parameter, which is always in seconds, and some
routing cache values, which are in USER_HZ, so both cases are broken
anyway.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:26:15 -07:00
Patrick McHardy
00c04af9df [NET_SCHED]: kill jiffie conversion macros
Now that all packet schedulers have been converted to hrtimers most users
of PSCHED_JIFFIE2US and PSCHED_US2JIFFIE are gone. The remaining users use
it to convert external time units to packet scheduler clock ticks, so use
PSCHED_TICKS_PER_SEC instead.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:26:14 -07:00
Patrick McHardy
fb983d4578 [NET_SCHED]: sch_htb: use hrtimer based watchdog
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:26:13 -07:00
Patrick McHardy
1a13cb63d6 [NET_SCHED]: sch_cbq: use hrtimer for delay_timer
Switch delay_timer to hrtimer.

The class penalty parameter is changed to use psched ticks as units.
Since iproute never supported using this and the only existing user
(libnl) incorrectly assumes psched ticks as units anyway, this
shouldn't break anything.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:26:12 -07:00
Patrick McHardy
e9054a339e [NET_SCHED]: sch_cbq: fix cbq_undelay_prio for non-active priorites
cbq_undelay_prio is supposed to return a time delta, but returns the
current time for non-active priorities, causing cbq_undelay to mark
the priority as active and schedule a timer for twice the current
time.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:26:11 -07:00
Patrick McHardy
88a993540a [NET_SCHED]: sch_cbq: use hrtimer based watchdog
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:26:09 -07:00
Patrick McHardy
59cb5c6734 [NET_SCHED]: sch_netem: use hrtimer based watchdog
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:26:08 -07:00
Patrick McHardy
f7f593e383 [NET_SCHED]: sch_tbf: use hrtimer based watchdog
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:26:07 -07:00
Patrick McHardy
ed2b229a97 [NET_SCHED]: sch_hfsc: use hrtimer based watchdog
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:26:06 -07:00
Patrick McHardy
4179477f63 [NET_SCHED]: Add hrtimer based qdisc watchdog
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:26:05 -07:00
Patrick McHardy
641b9e0e8b [NET_SCHED]: Use ktime as clocksource
Get rid of the manual clock source selection mess and use ktime. Also
use a scalar representation, which allows to clean up pkt_sched.h a bit
more and results in less ktime_to_ns() calls in most cases.

The PSCHED_US2JIFFIE/PSCHED_JIFFIE2US macros are implemented quite
inefficient by this patch, following patches will convert all qdiscs
to hrtimers and get rid of them entirely.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:26:04 -07:00
Arnaldo Carvalho de Melo
ddc7b8e32b [SK_BUFF]: Some more layer header conversions
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:26:03 -07:00
Arnaldo Carvalho de Melo
0a6114d94b [KBUILD]: Unifdef headers changed by the skb layer header refactorings
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:26:02 -07:00
Arnaldo Carvalho de Melo
d10ba34b00 [SK_BUFF]: More skb_put related skb_reset_transport_header
This time we have to set it to skb->tail that is not anymore equal to
skb->data, so we either add a new helper or just add the skb->tail - skb->data
offset, for now do the later.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:26:01 -07:00
Arnaldo Carvalho de Melo
55f79cc0c0 [IPV6]: Reset the network header in ip6_nd_hdr
ip6_nd_hdr is always called immediately after a alloc_skb + skb_reserve
sequence, i.e. when skb->tail is equal to skb->data, making it correct to use
skb_reset_network_header().

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:26:00 -07:00
Arnaldo Carvalho de Melo
eeeb03745b [SK_BUFF]: More skb_put related conversions to skb_reset_transport_header
This is similar to the skb_reset_network_header(), i.e. at the point we reset
the transport header pointer/offset skb->tail is equal to skb->data.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:25:59 -07:00
Pablo Neira Ayuso
ac6d141dc7 [NETFILTER]: nfnetlink: parse attributes with nfattr_parse in nfnetlink_check_attribute
Use nfattr_parse to parse attributes, this patch also modifies the default
behaviour since unknown attributes will be ignored instead of returning
EINVAL. This ensure backward compatibility: new libraries with new
attributes and old kernels can work.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:25:58 -07:00
Pablo Neira Ayuso
c8e2078cfe [NETFILTER]: ctnetlink: add support for internal tcp connection tracking flags handling
This patch let userspace programs set the IP_CT_TCP_BE_LIBERAL flag to
force the pickup of established connections.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:25:57 -07:00
Willy Tarreau
5c8ce7c921 [NETFILTER]: TCP conntrack: factorize out the PUSH flag
The PUSH flag is accepted with every other valid combination.
Let's get it out of the tcp_valid_flags table and reduce the
number of combinations we have to handle. This does not
significantly reduce the table size however (8 bytes).

Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:25:56 -07:00
Willy Tarreau
8f5bd99071 [NETFILTER]: TCP conntrack: accept RST|PSH as valid
This combination has been encountered on an IBM AS/400 in response
to packets sent to a closed session. There is no particular reason
to mark it invalid.

Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:25:56 -07:00
Yasuyuki Kozakai
e7ac05f340 [NETFILTER]: nf_conntrack: add nf_copy() to safely copy members in skb
This unifies the codes to copy netfilter related datas. Before copying,
nf_copy() puts original members in destination skb.

Signed-off-by: Yasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:25:55 -07:00
Yasuyuki Kozakai
edda553c32 [NETFILTER]: nf_conntrack: add __nf_copy() to copy members in skb
This unifies the codes to copy netfilter related datas. Note that
__nf_copy() assumes destination skb doesn't have any netfilter
related members.

Signed-off-by: Yasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:25:54 -07:00
Sami Farin
9b88790972 [NETFILTER]: nf_conntrack: use jhash2 in __hash_conntrack
Now it uses jhash, but using jhash2 would be around 3-4 times faster
(on P4).

Signed-off-by: Sami Farin <safari-netfilter@safari.iki.fi>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:25:53 -07:00
Patrick McHardy
8e87e014ec [JHASH]: Use const in jhash2
Use const to avoid forcing users to cast const data.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:25:52 -07:00
Pablo Neira Ayuso
f4bc177f0f [NETFILTER]: nfnetlink: move EXPORT_SYMBOL declarations next to the exported symbol
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:25:51 -07:00
Pablo Neira Ayuso
8a2e89533a [NETFILTER]: nfnetlink: remove unused includes in nfnetlink.c
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:25:50 -07:00
Pablo Neira Ayuso
ac0f1d9894 [NETFILTER]: nfnetlink: remove unrequired check in nfnetlink_get_subsys
subsys_table is initialized to NULL, therefore just returns NULL in case
that it is not set.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:25:49 -07:00
Pablo Neira Ayuso
d9e6d02949 [NETFILTER]: nfnetlink: remove duplicate checks in nfnetlink_check_attributes
Remove nfnetlink_check_attributes duplicates message size and callback
id checks. nfnetlink_find_client and nfnetlink_rcv_msg already do
such checks.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:25:48 -07:00
Pablo Neira Ayuso
67ca396606 [NETFILTER]: nfnetlink: remove early debugging messages from nfnetlink
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:25:47 -07:00
Patrick McHardy
010c7d6f86 [NETFILTER]: nf_conntrack: uninline notifier registration functions
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:25:46 -07:00
Patrick McHardy
73c361862c [NETFILTER]: nfnetlink: use netlink_run_queue()
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:25:44 -07:00