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Robert Olsson
2f36895aa7 [IPV4]: More broken memory allocation fixes for fib_trie
Below a patch to preallocate memory when doing resize of trie (inflate halve)
If preallocations fails it just skips the resize of this tnode for this time.

The oops we got when killing bgpd (with full routing) is now gone. 
Patrick memory patch is also used.

Signed-off-by: Robert Olsson <robert.olsson@its.uu.se>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-05 15:02:40 -07:00
Eric Dumazet
bb1d23b026 [IPV4]: Bug fix in rt_check_expire()
- rt_check_expire() fixes (an overflow occured if size of the hash
  was >= 65536)

reminder of the bugfix:

The rt_check_expire() has a serious problem on machines with large
route caches, and a standard HZ value of 1000.

With default values, ie ip_rt_gc_interval = 60*HZ = 60000 ;

the loop count :

     for (t = ip_rt_gc_interval << rt_hash_log; t >= 0;


overflows (t is a 31 bit value) as soon rt_hash_log is >= 16  (65536
slots in route cache hash table).

In this case, rt_check_expire() does nothing at all

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-05 15:00:32 -07:00
Eric Dumazet
424c4b70cc [IPV4]: Use the fancy alloc_large_system_hash() function for route hash table
- rt hash table allocated using alloc_large_system_hash() function.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-05 14:58:19 -07:00
Eric Dumazet
22c047ccbc [NET]: Hashed spinlocks in net/ipv4/route.c
- Locking abstraction
- Spinlocks moved out of rt hash table : Less memory (50%) used by rt 
  hash table. it's a win even on UP.
- Sizing of spinlocks table depends on NR_CPUS

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-05 14:55:24 -07:00
f0e36f8cee [IPV4]: Handle large allocations in fib_trie
Inflating a node a couple of times makes it exceed the 128k kmalloc limit.
Use __get_free_pages for allocations > PAGE_SIZE, as in fib_hash.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Acked-by: Robert Olsson <Robert.Olsson@data.slu.se>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-05 14:44:55 -07:00
Herbert Xu
30e224d76f [IPV4]: Fix crash in ip_rcv while booting related to netconsole
Makes IPv4 ip_rcv registration happen last in af_inet.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-05 14:40:10 -07:00
Thomas Graf
e176fe8954 [NET]: Remove unused security member in sk_buff
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-05 14:12:44 -07:00
9666dae510 [NETFILTER]: Fix connection tracking bug in 2.6.12
In 2.6.12 we started dropping the conntrack reference when a packet
leaves the IP layer. This broke connection tracking on a bridge,
because bridge-netfilter defers calling some NF_IP_* hooks to the bridge
layer for locally generated packets going out a bridge, where the
conntrack reference is no longer available. This patch keeps the
reference in this case as a temporary solution, long term we will
remove the defered hook calling. No attempt is made to drop the
reference in the bridge-code when it is no longer needed, tc actions
could already have sent the packet anywhere.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-28 16:04:44 -07:00
Neil Horman
fb3d89498d [IPVS]: Close race conditions on ip_vs_conn_tab list modification
In an smp system, it is possible for an connection timer to expire, calling
ip_vs_conn_expire while the connection table is being flushed, before
ct_write_lock_bh is acquired.

Since the list iterator loop in ip_vs_con_flush releases and re-acquires the
spinlock (even though it doesn't re-enable softirqs), it is possible for the
expiration function to modify the connection list, while it is being traversed
in ip_vs_conn_flush.

The result is that the next pointer gets set to NULL, and subsequently
dereferenced, resulting in an oops.

Signed-off-by: Neil Horman <nhorman@redhat.com>
Acked-by: JulianAnastasov
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-28 15:40:02 -07:00
Robert Olsson
f835e471b5 [IPV4]: Broken memory allocation in fib_trie
This should help up the insertion... but the resize is more crucial.
and complex and needs some thinking. 

Signed-off-by: Robert Olsson <robert.olsson@its.uu.se>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-28 15:00:39 -07:00
Maxime Bizon
7a1af5d7bb [IPV4]: ipconfig.c: fix dhcp timeout behaviour
I think there is a small bug in ipconfig.c in case IPCONFIG_DHCP is set
and dhcp is used.

When a DHCPOFFER is received, ip address is kept until we get DHCPACK.
If no ack is received, ic_dynamic() returns negatively, but leaves the
offered ip address in ic_myaddr.

This makes the main loop in ip_auto_config() break and uses the maybe
incomplete configuration.

Not sure if it's the best way to do, but the following trivial patch
correct this. 

Signed-off-by: Maxime Bizon <mbizon@freebox.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-28 13:21:12 -07:00
Dietmar Eggemann
2c2910a401 [IPV4]: Snmpv2 Mib IP counter ipInAddrErrors support
I followed Thomas' proposal to see every martian destination as a case
where the ipInAddrErrors counter has to be incremented. There are
two advantages by doing so: (1) The relation between the ipInReceive
counter and all the other ipInXXX counters is more accurate in the
case the RTN_UNICAST code check fails and (2) it makes the code in
ip_route_input_slow easier.

Signed-off-by: Dietmar Eggemann <dietmar.eggemann@gmx.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-28 13:06:23 -07:00
9ef1d4c7c7 [NETLINK]: Missing initializations in dumped data
Mostly missing initialization of padding fields of 1 or 2 bytes length,
two instances of uninitialized nlmsgerr->msg of 16 bytes length.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-28 12:55:30 -07:00
Harald Welte
4095ebf1e6 [NETFILTER]: ipt_CLUSTERIP: fix ARP mangling
This patch adds mangling of ARP requests (in addition to replies),
since ARP caches are made from snooping both requests and replies.

Signed-off-by: Harald Welte <laforge@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-28 12:49:30 -07:00
pageexec
4da62fc70d [IPVS]: Fix for overflows
From: <pageexec@freemail.hu>

$subject was fixed in 2.4 already, 2.6 needs it as well.

The impact of the bugs is a kernel stack overflow and privilege escalation
from CAP_NET_ADMIN via the IP_VS_SO_SET_STARTDAEMON/IP_VS_SO_GET_DAEMON
ioctls.  People running with 'root=all caps' (i.e., most users) are not
really affected (there's nothing to escalate), but SELinux and similar
users should take it seriously if they grant CAP_NET_ADMIN to other users.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-26 16:00:19 -07:00
Adrian Bunk
60fe740320 [TCP]: Let TCP_CONG_ADVANCED default to n
It doesn't seem to make much sense to let an "If unsure, say N." option 
default to y.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-26 15:21:15 -07:00
David S. Miller
6c3607676c [IPV4]: Fix thinko in TCP_CONG_BIC default.
Since it is tristate when we offer it as a choice, we should
definte it also as tristate when forcing it as the default.
Otherwise kconfig warns.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-26 15:20:20 -07:00
David S. Miller
a6484045fd [TCP]: Do not present confusing congestion control options by default.
Create TCP_CONG_ADVANCED option, akin to IP_ADVANCED_ROUTER, which
when disabled will bypass all of the congestion control Kconfig
options and leave the user with a safe default.

That safe default is currently BIC-TCP with new Reno as a fallback.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-24 18:07:51 -07:00
David S. Miller
bb298ca3ce [IPV4]: Move FIB lookup algorithm choice under IP_ADVANCED_ROUTING
Most users need not be concerned with a complex choice of what
FIB lookup algorithm to use.  So give them the safe default of
IP_FIB_HASH if IP_ADVANCED_ROUTING is disabled.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-24 17:50:53 -07:00
Stephen Hemminger
5f8ef48d24 [TCP]: Allow choosing TCP congestion control via sockopt.
Allow using setsockopt to set TCP congestion control to use on a per
socket basis.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-23 20:37:36 -07:00
John Heffner
0e57976b63 [TCP]: Add Scalable TCP congestion control module.
This patch implements Tom Kelly's Scalable TCP congestion control algorithm 
for the modular framework.

The algorithm has some nice scaling properties, and has been used a fair bit 
in research, though is known to have significant fairness issues, so it's not 
really suitable for general purpose use.

Signed-off-by: John Heffner <jheffner@psc.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-23 12:29:07 -07:00
Baruch Even
a7868ea68d [TCP]: Add H-TCP congestion control module.
H-TCP is a congestion control algorithm developed at the Hamilton Institute, by
Douglas Leith and Robert Shorten. It is extending the standard Reno algorithm
with mode switching is thus a relatively simple modification.

H-TCP is defined in a layered manner as it is still a research platform. The
basic form includes the modification of beta according to the ratio of maxRTT
to min RTT and the alpha=2*factor*(1-beta) relation, where factor is dependant
on the time since last congestion.

The other layers improve convergence by adding appropriate factors to alpha.

The following patch implements the H-TCP algorithm in it's basic form.

Signed-Off-By: Baruch Even <baruch@ev-en.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-23 12:28:11 -07:00
Stephen Hemminger
b87d8561d8 [TCP]: Add TCP Vegas congestion control module.
TCP Vegas code modified for the new TCP infrastructure.  
Vegas now uses microsecond resolution timestamps for 
better estimation of performance over higher speed links.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-23 12:27:19 -07:00
Daniele Lacamera
835b3f0c0d [TCP]: Add TCP Hybla congestion control module.
TCP Hybla congestion avoidance.

- "In heterogeneous networks, TCP connections that incorporate a
terrestrial or satellite radio link are greatly disadvantaged with
respect to entirely wired connections, because of their longer round
trip times (RTTs). To cope with this problem, a new TCP proposal, the
TCP Hybla, is presented and discussed in the paper[1]. It stems from an
analytical evaluation of the congestion window dynamics in the TCP
standard versions (Tahoe, Reno, NewReno), which suggests the necessary
modifications to remove the performance dependence on RTT.[...]"[1]

[1]: Carlo Caini, Rosario Firrincieli, "TCP Hybla: a TCP enhancement for
heterogeneous networks",
International Journal of Satellite Communications and Networking
Volume 22, Issue 5 , Pages 547 - 566. September 2004.

Signed-off-by: Daniele Lacamera (root at danielinux.net)net
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-23 12:26:34 -07:00
John Heffner
a628d29b56 [TCP]: Add High Speed TCP congestion control module.
Sally Floyd's high speed TCP congestion control.
This is useful for comparison and research.

Signed-off-by: John Heffner <jheffner@psc.edu>
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-23 12:24:58 -07:00
Stephen Hemminger
8727076289 [TCP]: Add TCP Westwood congestion control module.
This is the existing 2.6.12 Westwood code moved from tcp_input
to the new congestion framework. A lot of the inline functions
have been eliminated to try and make it clearer.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-23 12:24:09 -07:00
Stephen Hemminger
83803034f4 [TCP]: Add TCP BIC congestion control module.
TCP BIC congestion control reworked to use the new congestion control 
infrastructure. This version is more up to date than the BIC
code in 2.6.12; it incorporates enhancements from BICTCP 1.1, 
to handle low latency links.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-23 12:23:25 -07:00
Stephen Hemminger
056ede6cfa [TCP]: Report congestion control algorithm in tcp_diag.
Enhancement to the tcp_diag interface used by the iproute2 ss command
to report the tcp congestion control being used by a socket.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-23 12:21:28 -07:00
Stephen Hemminger
7c99c909fa [TCP]: Change tcp_diag to use the existing __RTA_PUT() macro.
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-23 12:20:36 -07:00
Stephen Hemminger
317a76f9a4 [TCP]: Add pluggable congestion control algorithm infrastructure.
Allow TCP to have multiple pluggable congestion control algorithms.
Algorithms are defined by a set of operations and can be built in
or modules.  The legacy "new RENO" algorithm is used as a starting
point and fallback.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-23 12:19:55 -07:00
Paulo Marques
543537bd92 [PATCH] create a kstrdup library function
This patch creates a new kstrdup library function and changes the "local"
implementations in several places to use this function.

Most of the changes come from the sound and net subsystems.  The sound part
had already been acknowledged by Takashi Iwai and the net part by David S.
Miller.

I left UML alone for now because I would need more time to read the code
carefully before making changes there.

Signed-off-by: Paulo Marques <pmarques@grupopie.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 09:45:18 -07:00
Chuck Short
7abaa27c1c [IPV4]: Fix route.c gcc4 warnings
Signed-off by: Chuck Short <zulcss@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-22 22:10:23 -07:00
Harald Welte
5d927eb010 [NETFILTER]: Fix handling of ICMP packets (RELATED) in ipt_CLUSTERIP target.
Signed-off-by: Harald Welte <laforge@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-22 12:37:50 -07:00
Kumar Gala
b535420739 [PATCH] Fix extra double quote in IPV4 Kconfig
Kconfig option had an extra double quote at the end of the line
which was causing in warning when building.

Signed-off-by: Kumar Gala <kumar.gala@freescale.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-22 10:40:39 -07:00
David S. Miller
90f66914c8 [IPV4]: Fix fib_trie.c's args to fib_dump_info().
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-21 14:43:28 -07:00
2715bcf9ef [NETFILTER]: Drop conntrack reference in ip_call_ra_chain()/ip_mr_input()
Drop reference before handing the packets to raw_rcv()

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-21 14:06:24 -07:00
6150bacfec [NETFILTER]: Check TCP checksum in ipt_REJECT
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-21 14:03:46 -07:00
Keir Fraser
e3be8ba792 [NETFILTER]: Avoid unncessary checksum validation in UDP connection tracking
Signed-off-by: Keir Fraser <Keir.Fraser@xl.cam.ac.uk>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-21 14:03:23 -07:00
Phil Oester
1d3cdb41f5 [NETFILTER]: expectation timeouts are compulsory
Since expectation timeouts were made compulsory [1], there is no need to
check for them in ip_conntrack_expect_insert.

[1] https://lists.netfilter.org/pipermail/netfilter-devel/2005-January/018143.html

Signed-off-by: Phil Oester <kernel@linuxace.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-21 14:02:42 -07:00
18b8afc771 [NETFILTER]: Kill nf_debug
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-21 14:01:57 -07:00
e45b1be8bc [NETFILTER]: Kill lockhelp.h
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-21 14:01:30 -07:00
Robert Olsson
19baf839ff [IPV4]: Add LC-Trie FIB lookup algorithm.
Signed-off-by: Robert Olsson <Robert.Olsson@data.slu.se>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-21 12:43:18 -07:00
Robert Olsson
246955fe4c [NETLINK]: fib_lookup() via netlink
Below is a more generic patch to do fib_lookup via netlink. For others 
we should say that we discussed this as a way to verify route selection.
It's also possible there are others uses for this.

In short the fist half of struct fib_result_nl is filled in by caller 
and netlink call fills in the other half and returns it.

In case anyone is interested there is a corresponding user app to compare 
the full routing table this was used to test implementation of the LC-trie. 

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-20 13:36:39 -07:00
Herbert Xu
dd87147eed [IPSEC]: Add XFRM_STATE_NOPMTUDISC flag
This patch adds the flag XFRM_STATE_NOPMTUDISC for xfrm states.  It is
similar to the nopmtudisc on IPIP/GRE tunnels.  It only has an effect
on IPv4 tunnel mode states.  For these states, it will ensure that the
DF flag is always cleared.

This is primarily useful to work around ICMP blackholes.

In future this flag could also allow a larger MTU to be set within the
tunnel just like IPIP/GRE tunnels.  This could be useful for short haul
tunnels where temporary fragmentation outside the tunnel is desired over
smaller fragments inside the tunnel.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: James Morris <jmorris@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-20 13:21:43 -07:00
Herbert Xu
72cb6962a9 [IPSEC]: Add xfrm_init_state
This patch adds xfrm_init_state which is simply a wrapper that calls
xfrm_get_type and subsequently x->type->init_state.  It also gets rid
of the unused args argument.

Abstracting it out allows us to add common initialisation code, e.g.,
to set family-specific flags.

The add_time setting in xfrm_user.c was deleted because it's already
set by xfrm_state_alloc.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: James Morris <jmorris@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-20 13:18:08 -07:00
David S. Miller
7df551254a [TCP]: Fix sysctl_tcp_low_latency
When enabled, this should disable UCOPY prequeue'ing altogether,
but it does not due to a missing test.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-18 23:01:10 -07:00
Jesper Juhl
f7d7fc0322 [IPV4]: [4/4] signed vs unsigned cleanup in net/ipv4/raw.c
This patch changes the type of the third parameter 'length' of the 
raw_send_hdrinc() function from 'int' to 'size_t'.
This makes sense since this function is only ever called from one 
location, and the value passed as the third parameter in that location is 
itself of type size_t, so this makes the recieving functions parameter 
type match. Also, inside raw_send_hdrinc() the 'length' variable is 
used in comparisons with unsigned values and passed as parameter to 
functions expecting unsigned values (it's used in a single comparison with 
a signed value, but that one can never actually be negative so the patch 
also casts that one to size_t to stop gcc worrying, and it is passed in a 
single instance to memcpy_fromiovecend() which expects a signed int, but 
as far as I can see that's not a problem since the value of 'length' 
shouldn't ever exceed the value of a signed int).

Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-18 23:00:34 -07:00
Jesper Juhl
93765d8a43 [IPV4]: [3/4] signed vs unsigned cleanup in net/ipv4/raw.c
This patch changes the type of the local variable 'i' in 
raw_probe_proto_opt() from 'int' to 'unsigned int'. The only use of 'i' in 
this function is as a counter in a for() loop and subsequent index into 
the msg->msg_iov[] array.
Since 'i' is compared in a loop to the unsigned variable msg->msg_iovlen 
gcc -W generates this warning : 

net/ipv4/raw.c:340: warning: comparison between signed and unsigned

Changing 'i' to unsigned silences this warning and is safe since the array 
index can never be negative anyway, so unsigned int is the logical type to 
use for 'i' and also enables a larger msg_iov[] array (but I don't know if 
that will ever matter).

Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-18 23:00:15 -07:00
Jesper Juhl
926d4b8122 [IPV4]: [2/4] signed vs unsigned cleanup in net/ipv4/raw.c
This patch gets rid of the following gcc -W warning in net/ipv4/raw.c :

net/ipv4/raw.c:387: warning: comparison of unsigned expression < 0 is always false

Since 'len' is of type size_t it is unsigned and can thus never be <0, and 
since this is obvious from the function declaration just a few lines above 
I think it's ok to remove the pointless check for len<0.


Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-18 23:00:00 -07:00
Jesper Juhl
5418c6926f [IPV4]: [1/4] signed vs unsigned cleanup in net/ipv4/raw.c
This patch silences these two gcc -W warnings in net/ipv4/raw.c :

net/ipv4/raw.c:517: warning: signed and unsigned type in conditional expression
net/ipv4/raw.c:613: warning: signed and unsigned type in conditional expression

It doesn't change the behaviour of the code, simply writes the conditional 
expression with plain 'if()' syntax instead of '? :' , but since this 
breaks it into sepperate statements gcc no longer complains about having 
both a signed and unsigned value in the same conditional expression.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-18 22:59:45 -07:00