* [PATCHv2] Bluetooth: Send a configuration request after security confirmation
@ 2012-05-22 20:55 Mat Martineau
2012-05-23 3:12 ` Marcel Holtmann
2012-05-23 8:20 ` [PATCHv2] " Andrei Emeltchenko
0 siblings, 2 replies; 6+ messages in thread
From: Mat Martineau @ 2012-05-22 20:55 UTC (permalink / raw)
To: linux-bluetooth, gustavo, marcel; +Cc: pkrystad
Sometimes an ACL link must be raised to a higher security level after
an L2CAP connection is requested, but before a connection response is
sent. In this case, a connection response sent by L2CAP was not
immediately followed by a configuration request. Other code paths do
send this configuration request right away. It was possible for the
connection to time out while L2CAP waited for the remote device (like
PTS) to trigger the configuration process.
This change immediately sends a configuration request after a connect
response rather than waiting for a configuration request from the
remote device. It fixes connection stalls in a variety of PTS test
cases.
Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
---
net/bluetooth/l2cap_core.c | 11 +++++++++++
1 file changed, 11 insertions(+)
diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c
index b644f40..14c27f4 100644
--- a/net/bluetooth/l2cap_core.c
+++ b/net/bluetooth/l2cap_core.c
@@ -5519,6 +5519,17 @@ int l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt)
rsp.status = cpu_to_le16(stat);
l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
sizeof(rsp), &rsp);
+
+ if (!test_bit(CONF_REQ_SENT, &chan->conf_state) &&
+ res == L2CAP_CR_SUCCESS) {
+ char buf[128];
+ set_bit(CONF_REQ_SENT, &chan->conf_state);
+ l2cap_send_cmd(conn, l2cap_get_ident(conn),
+ L2CAP_CONF_REQ,
+ l2cap_build_conf_req(chan, buf),
+ buf);
+ chan->num_conf_req++;
+ }
}
l2cap_chan_unlock(chan);
--
1.7.10
--
Mat Martineau
Employee of Qualcomm Innovation Center, Inc.
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCHv2] Bluetooth: Send a configuration request after security confirmation
2012-05-22 20:55 [PATCHv2] Bluetooth: Send a configuration request after security confirmation Mat Martineau
@ 2012-05-23 3:12 ` Marcel Holtmann
2012-05-23 21:59 ` [PATCHv3] " Mat Martineau
2012-05-23 8:20 ` [PATCHv2] " Andrei Emeltchenko
1 sibling, 1 reply; 6+ messages in thread
From: Marcel Holtmann @ 2012-05-23 3:12 UTC (permalink / raw)
To: Mat Martineau; +Cc: linux-bluetooth, gustavo, pkrystad
Hi Mat,
> Sometimes an ACL link must be raised to a higher security level after
> an L2CAP connection is requested, but before a connection response is
> sent. In this case, a connection response sent by L2CAP was not
> immediately followed by a configuration request. Other code paths do
> send this configuration request right away. It was possible for the
> connection to time out while L2CAP waited for the remote device (like
> PTS) to trigger the configuration process.
>
> This change immediately sends a configuration request after a connect
> response rather than waiting for a configuration request from the
> remote device. It fixes connection stalls in a variety of PTS test
> cases.
any change you can add a before and after hcidump in the commit message?
Regards
Marcel
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCHv2] Bluetooth: Send a configuration request after security confirmation
2012-05-22 20:55 [PATCHv2] Bluetooth: Send a configuration request after security confirmation Mat Martineau
2012-05-23 3:12 ` Marcel Holtmann
@ 2012-05-23 8:20 ` Andrei Emeltchenko
1 sibling, 0 replies; 6+ messages in thread
From: Andrei Emeltchenko @ 2012-05-23 8:20 UTC (permalink / raw)
To: Mat Martineau; +Cc: linux-bluetooth, gustavo, marcel, pkrystad
Hi Mat,
On Tue, May 22, 2012 at 01:55:45PM -0700, Mat Martineau wrote:
> Sometimes an ACL link must be raised to a higher security level after
> an L2CAP connection is requested, but before a connection response is
> sent. In this case, a connection response sent by L2CAP was not
> immediately followed by a configuration request. Other code paths do
> send this configuration request right away. It was possible for the
> connection to time out while L2CAP waited for the remote device (like
> PTS) to trigger the configuration process.
>
> This change immediately sends a configuration request after a connect
> response rather than waiting for a configuration request from the
> remote device. It fixes connection stalls in a variety of PTS test
> cases.
>
> Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
> ---
> net/bluetooth/l2cap_core.c | 11 +++++++++++
> 1 file changed, 11 insertions(+)
>
> diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c
> index b644f40..14c27f4 100644
> --- a/net/bluetooth/l2cap_core.c
> +++ b/net/bluetooth/l2cap_core.c
> @@ -5519,6 +5519,17 @@ int l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt)
> rsp.status = cpu_to_le16(stat);
> l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
> sizeof(rsp), &rsp);
> +
> + if (!test_bit(CONF_REQ_SENT, &chan->conf_state) &&
> + res == L2CAP_CR_SUCCESS) {
This looks more readable but I think we used to have constructions like
!status so this would translate to !res
Best regards
Andrei Emeltchenko
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCHv3] Bluetooth: Send a configuration request after security confirmation
2012-05-23 3:12 ` Marcel Holtmann
@ 2012-05-23 21:59 ` Mat Martineau
2012-05-24 0:28 ` Marcel Holtmann
0 siblings, 1 reply; 6+ messages in thread
From: Mat Martineau @ 2012-05-23 21:59 UTC (permalink / raw)
To: linux-bluetooth, gustavo, marcel; +Cc: pkrystad
Sometimes an ACL link must be raised to a higher security level after
an L2CAP connection is requested, but before a connection response is
sent. In this case, a connection response sent by L2CAP was not
immediately followed by a configuration request. Other code paths do
send this configuration request right away. It was possible for the
connection to stall while L2CAP waited for the remote device (like
PTS) to trigger the configuration process.
Here is an abbreviated hcidump of the failure case with PTS:
1337806446.051982 > ACL data: handle 43 flags 0x02 dlen 10
L2CAP(s): Info req: type 2
1337806446.052050 < ACL data: handle 43 flags 0x00 dlen 16
L2CAP(s): Info rsp: type 2 result 0
Extended feature mask 0x000000b8
1337806446.595320 > ACL data: handle 43 flags 0x02 dlen 12
L2CAP(s): Connect req: psm 4097 scid 0x0041
1337806446.595673 < ACL data: handle 43 flags 0x00 dlen 16
L2CAP(s): Connect rsp: dcid 0x0040 scid 0x0041 result 1 status 0
1337806446.595679 < ACL data: handle 43 flags 0x00 dlen 10
L2CAP(s): Info req: type 2
1337806446.669835 > ACL data: handle 43 flags 0x02 dlen 16
L2CAP(s): Info rsp: type 2 result 0
Extended feature mask 0x00000028
1337806446.669899 < HCI Command: Authentication Requested (0x01|0x0011) plen 2
1337806446.669906 < ACL data: handle 43 flags 0x00 dlen 16
L2CAP(s): Connect rsp: dcid 0x0040 scid 0x0041 result 1 status 1
<security setup here>
1337806446.769888 < ACL data: handle 43 flags 0x00 dlen 16
L2CAP(s): Connect rsp: dcid 0x0040 scid 0x0041 result 0 status 0
At this point, the connection stalls and no further messages are sent
on the L2CAP signaling channel. No data is received either.
If we immediately send a configuration request after a successful connect
response, the connection completes:
1337724090.041162 > ACL data: handle 43 flags 0x02 dlen 10
L2CAP(s): Info req: type 2
1337724090.041236 < ACL data: handle 43 flags 0x00 dlen 16
L2CAP(s): Info rsp: type 2 result 0
Extended feature mask 0x000000b8
1337724090.597128 > ACL data: handle 43 flags 0x02 dlen 12
L2CAP(s): Connect req: psm 4097 scid 0x0041
1337724090.597236 < ACL data: handle 43 flags 0x00 dlen 16
L2CAP(s): Connect rsp: dcid 0x0040 scid 0x0041 result 1 status 0
1337724090.597244 < ACL data: handle 43 flags 0x00 dlen 10
L2CAP(s): Info req: type 2
1337724090.660842 > ACL data: handle 43 flags 0x02 dlen 16
L2CAP(s): Info rsp: type 2 result 0
Extended feature mask 0x00000028
1337724090.660926 < HCI Command: Authentication Requested (0x01|0x0011) plen 2
1337724090.660934 < ACL data: handle 43 flags 0x00 dlen 16
L2CAP(s): Connect rsp: dcid 0x0040 scid 0x0041 result 1 status 1
<security setup here>
1337724090.755162 < ACL data: handle 43 flags 0x00 dlen 16
L2CAP(s): Connect rsp: dcid 0x0040 scid 0x0041 result 0 status 0
1337724090.755171 < ACL data: handle 43 flags 0x00 dlen 23
L2CAP(s): Config req: dcid 0x0041 flags 0x00 clen 11
1337724091.361847 > ACL data: handle 43 flags 0x02 dlen 29
L2CAP(s): Config rsp: scid 0x0040 flags 0x00 result 0 clen 15
1337724091.863808 > ACL data: handle 43 flags 0x02 dlen 23
L2CAP(s): Config req: dcid 0x0040 flags 0x00 clen 11
1337724091.863882 < ACL data: handle 43 flags 0x00 dlen 29
L2CAP(s): Config rsp: scid 0x0041 flags 0x00 result 0 clen 15
1337724092.683745 > ACL data: handle 43 flags 0x02 dlen 12
L2CAP(d): cid 0x0040 len 8 [psm 4097]
0000: 00 00 11 22 33 44 34 2f ..."3D4/
Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
---
net/bluetooth/l2cap_core.c | 11 +++++++++++
1 file changed, 11 insertions(+)
diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c
index e31b005..c9e6ae4 100644
--- a/net/bluetooth/l2cap_core.c
+++ b/net/bluetooth/l2cap_core.c
@@ -5500,6 +5500,17 @@ int l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt)
rsp.status = cpu_to_le16(stat);
l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
sizeof(rsp), &rsp);
+
+ if (!test_bit(CONF_REQ_SENT, &chan->conf_state) &&
+ res == L2CAP_CR_SUCCESS) {
+ char buf[128];
+ set_bit(CONF_REQ_SENT, &chan->conf_state);
+ l2cap_send_cmd(conn, l2cap_get_ident(conn),
+ L2CAP_CONF_REQ,
+ l2cap_build_conf_req(chan, buf),
+ buf);
+ chan->num_conf_req++;
+ }
}
l2cap_chan_unlock(chan);
--
1.7.10
--
Mat Martineau
Employee of Qualcomm Innovation Center, Inc.
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCHv3] Bluetooth: Send a configuration request after security confirmation
2012-05-23 21:59 ` [PATCHv3] " Mat Martineau
@ 2012-05-24 0:28 ` Marcel Holtmann
2012-05-24 0:33 ` Gustavo Padovan
0 siblings, 1 reply; 6+ messages in thread
From: Marcel Holtmann @ 2012-05-24 0:28 UTC (permalink / raw)
To: Mat Martineau; +Cc: linux-bluetooth, gustavo, pkrystad
Hi Mat,
> Sometimes an ACL link must be raised to a higher security level after
> an L2CAP connection is requested, but before a connection response is
> sent. In this case, a connection response sent by L2CAP was not
> immediately followed by a configuration request. Other code paths do
> send this configuration request right away. It was possible for the
> connection to stall while L2CAP waited for the remote device (like
> PTS) to trigger the configuration process.
>
> Here is an abbreviated hcidump of the failure case with PTS:
>
> 1337806446.051982 > ACL data: handle 43 flags 0x02 dlen 10
> L2CAP(s): Info req: type 2
> 1337806446.052050 < ACL data: handle 43 flags 0x00 dlen 16
> L2CAP(s): Info rsp: type 2 result 0
> Extended feature mask 0x000000b8
> 1337806446.595320 > ACL data: handle 43 flags 0x02 dlen 12
> L2CAP(s): Connect req: psm 4097 scid 0x0041
> 1337806446.595673 < ACL data: handle 43 flags 0x00 dlen 16
> L2CAP(s): Connect rsp: dcid 0x0040 scid 0x0041 result 1 status 0
> 1337806446.595679 < ACL data: handle 43 flags 0x00 dlen 10
> L2CAP(s): Info req: type 2
> 1337806446.669835 > ACL data: handle 43 flags 0x02 dlen 16
> L2CAP(s): Info rsp: type 2 result 0
> Extended feature mask 0x00000028
> 1337806446.669899 < HCI Command: Authentication Requested (0x01|0x0011) plen 2
> 1337806446.669906 < ACL data: handle 43 flags 0x00 dlen 16
> L2CAP(s): Connect rsp: dcid 0x0040 scid 0x0041 result 1 status 1
> <security setup here>
> 1337806446.769888 < ACL data: handle 43 flags 0x00 dlen 16
> L2CAP(s): Connect rsp: dcid 0x0040 scid 0x0041 result 0 status 0
>
> At this point, the connection stalls and no further messages are sent
> on the L2CAP signaling channel. No data is received either.
>
> If we immediately send a configuration request after a successful connect
> response, the connection completes:
>
> 1337724090.041162 > ACL data: handle 43 flags 0x02 dlen 10
> L2CAP(s): Info req: type 2
> 1337724090.041236 < ACL data: handle 43 flags 0x00 dlen 16
> L2CAP(s): Info rsp: type 2 result 0
> Extended feature mask 0x000000b8
> 1337724090.597128 > ACL data: handle 43 flags 0x02 dlen 12
> L2CAP(s): Connect req: psm 4097 scid 0x0041
> 1337724090.597236 < ACL data: handle 43 flags 0x00 dlen 16
> L2CAP(s): Connect rsp: dcid 0x0040 scid 0x0041 result 1 status 0
> 1337724090.597244 < ACL data: handle 43 flags 0x00 dlen 10
> L2CAP(s): Info req: type 2
> 1337724090.660842 > ACL data: handle 43 flags 0x02 dlen 16
> L2CAP(s): Info rsp: type 2 result 0
> Extended feature mask 0x00000028
> 1337724090.660926 < HCI Command: Authentication Requested (0x01|0x0011) plen 2
> 1337724090.660934 < ACL data: handle 43 flags 0x00 dlen 16
> L2CAP(s): Connect rsp: dcid 0x0040 scid 0x0041 result 1 status 1
> <security setup here>
> 1337724090.755162 < ACL data: handle 43 flags 0x00 dlen 16
> L2CAP(s): Connect rsp: dcid 0x0040 scid 0x0041 result 0 status 0
> 1337724090.755171 < ACL data: handle 43 flags 0x00 dlen 23
> L2CAP(s): Config req: dcid 0x0041 flags 0x00 clen 11
> 1337724091.361847 > ACL data: handle 43 flags 0x02 dlen 29
> L2CAP(s): Config rsp: scid 0x0040 flags 0x00 result 0 clen 15
> 1337724091.863808 > ACL data: handle 43 flags 0x02 dlen 23
> L2CAP(s): Config req: dcid 0x0040 flags 0x00 clen 11
> 1337724091.863882 < ACL data: handle 43 flags 0x00 dlen 29
> L2CAP(s): Config rsp: scid 0x0041 flags 0x00 result 0 clen 15
> 1337724092.683745 > ACL data: handle 43 flags 0x02 dlen 12
> L2CAP(d): cid 0x0040 len 8 [psm 4097]
> 0000: 00 00 11 22 33 44 34 2f ..."3D4/
>
> Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
> ---
> net/bluetooth/l2cap_core.c | 11 +++++++++++
> 1 file changed, 11 insertions(+)
thanks for adding the hcidump data. Patch has been applied to
bluetooth-next tree.
> diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c
> index e31b005..c9e6ae4 100644
> --- a/net/bluetooth/l2cap_core.c
> +++ b/net/bluetooth/l2cap_core.c
> @@ -5500,6 +5500,17 @@ int l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt)
> rsp.status = cpu_to_le16(stat);
> l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
> sizeof(rsp), &rsp);
> +
We do have a coding style issue with the existing l2cap_send_cmd here.
Is anybody going to fix that?
Regards
Marcel
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCHv3] Bluetooth: Send a configuration request after security confirmation
2012-05-24 0:28 ` Marcel Holtmann
@ 2012-05-24 0:33 ` Gustavo Padovan
0 siblings, 0 replies; 6+ messages in thread
From: Gustavo Padovan @ 2012-05-24 0:33 UTC (permalink / raw)
To: Marcel Holtmann; +Cc: Mat Martineau, linux-bluetooth, pkrystad
Hi Marcel,
* Marcel Holtmann <marcel@holtmann.org> [2012-05-24 02:28:04 +0200]:
> Hi Mat,
>
> > Sometimes an ACL link must be raised to a higher security level after
> > an L2CAP connection is requested, but before a connection response is
> > sent. In this case, a connection response sent by L2CAP was not
> > immediately followed by a configuration request. Other code paths do
> > send this configuration request right away. It was possible for the
> > connection to stall while L2CAP waited for the remote device (like
> > PTS) to trigger the configuration process.
> >
> > Here is an abbreviated hcidump of the failure case with PTS:
> >
> > 1337806446.051982 > ACL data: handle 43 flags 0x02 dlen 10
> > L2CAP(s): Info req: type 2
> > 1337806446.052050 < ACL data: handle 43 flags 0x00 dlen 16
> > L2CAP(s): Info rsp: type 2 result 0
> > Extended feature mask 0x000000b8
> > 1337806446.595320 > ACL data: handle 43 flags 0x02 dlen 12
> > L2CAP(s): Connect req: psm 4097 scid 0x0041
> > 1337806446.595673 < ACL data: handle 43 flags 0x00 dlen 16
> > L2CAP(s): Connect rsp: dcid 0x0040 scid 0x0041 result 1 status 0
> > 1337806446.595679 < ACL data: handle 43 flags 0x00 dlen 10
> > L2CAP(s): Info req: type 2
> > 1337806446.669835 > ACL data: handle 43 flags 0x02 dlen 16
> > L2CAP(s): Info rsp: type 2 result 0
> > Extended feature mask 0x00000028
> > 1337806446.669899 < HCI Command: Authentication Requested (0x01|0x0011) plen 2
> > 1337806446.669906 < ACL data: handle 43 flags 0x00 dlen 16
> > L2CAP(s): Connect rsp: dcid 0x0040 scid 0x0041 result 1 status 1
> > <security setup here>
> > 1337806446.769888 < ACL data: handle 43 flags 0x00 dlen 16
> > L2CAP(s): Connect rsp: dcid 0x0040 scid 0x0041 result 0 status 0
> >
> > At this point, the connection stalls and no further messages are sent
> > on the L2CAP signaling channel. No data is received either.
> >
> > If we immediately send a configuration request after a successful connect
> > response, the connection completes:
> >
> > 1337724090.041162 > ACL data: handle 43 flags 0x02 dlen 10
> > L2CAP(s): Info req: type 2
> > 1337724090.041236 < ACL data: handle 43 flags 0x00 dlen 16
> > L2CAP(s): Info rsp: type 2 result 0
> > Extended feature mask 0x000000b8
> > 1337724090.597128 > ACL data: handle 43 flags 0x02 dlen 12
> > L2CAP(s): Connect req: psm 4097 scid 0x0041
> > 1337724090.597236 < ACL data: handle 43 flags 0x00 dlen 16
> > L2CAP(s): Connect rsp: dcid 0x0040 scid 0x0041 result 1 status 0
> > 1337724090.597244 < ACL data: handle 43 flags 0x00 dlen 10
> > L2CAP(s): Info req: type 2
> > 1337724090.660842 > ACL data: handle 43 flags 0x02 dlen 16
> > L2CAP(s): Info rsp: type 2 result 0
> > Extended feature mask 0x00000028
> > 1337724090.660926 < HCI Command: Authentication Requested (0x01|0x0011) plen 2
> > 1337724090.660934 < ACL data: handle 43 flags 0x00 dlen 16
> > L2CAP(s): Connect rsp: dcid 0x0040 scid 0x0041 result 1 status 1
> > <security setup here>
> > 1337724090.755162 < ACL data: handle 43 flags 0x00 dlen 16
> > L2CAP(s): Connect rsp: dcid 0x0040 scid 0x0041 result 0 status 0
> > 1337724090.755171 < ACL data: handle 43 flags 0x00 dlen 23
> > L2CAP(s): Config req: dcid 0x0041 flags 0x00 clen 11
> > 1337724091.361847 > ACL data: handle 43 flags 0x02 dlen 29
> > L2CAP(s): Config rsp: scid 0x0040 flags 0x00 result 0 clen 15
> > 1337724091.863808 > ACL data: handle 43 flags 0x02 dlen 23
> > L2CAP(s): Config req: dcid 0x0040 flags 0x00 clen 11
> > 1337724091.863882 < ACL data: handle 43 flags 0x00 dlen 29
> > L2CAP(s): Config rsp: scid 0x0041 flags 0x00 result 0 clen 15
> > 1337724092.683745 > ACL data: handle 43 flags 0x02 dlen 12
> > L2CAP(d): cid 0x0040 len 8 [psm 4097]
> > 0000: 00 00 11 22 33 44 34 2f ..."3D4/
> >
> > Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
> > ---
> > net/bluetooth/l2cap_core.c | 11 +++++++++++
> > 1 file changed, 11 insertions(+)
>
> thanks for adding the hcidump data. Patch has been applied to
> bluetooth-next tree.
>
> > diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c
> > index e31b005..c9e6ae4 100644
> > --- a/net/bluetooth/l2cap_core.c
> > +++ b/net/bluetooth/l2cap_core.c
> > @@ -5500,6 +5500,17 @@ int l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt)
> > rsp.status = cpu_to_le16(stat);
> > l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
> > sizeof(rsp), &rsp);
> > +
>
> We do have a coding style issue with the existing l2cap_send_cmd here.
> Is anybody going to fix that?
I have plans to fix l2cap style like I did for the rest of the stack, but I'm
waiting we apply Andrei's patchset first, so we don't break his code.
Gustavo
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2012-05-24 0:33 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2012-05-22 20:55 [PATCHv2] Bluetooth: Send a configuration request after security confirmation Mat Martineau
2012-05-23 3:12 ` Marcel Holtmann
2012-05-23 21:59 ` [PATCHv3] " Mat Martineau
2012-05-24 0:28 ` Marcel Holtmann
2012-05-24 0:33 ` Gustavo Padovan
2012-05-23 8:20 ` [PATCHv2] " Andrei Emeltchenko
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