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Relaying mail using the AUTH-SMTP in Redhat 9

Posted on 2004-04-04
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I am able to pop and send mail with my outlook client in clear text.

Two questions.
1 Is it possible to use sasldb2 to authenticate the pop3. Not sure the settings that I need to make at the server.

2 How to solve the problem of relaying denied.

I have configured the sendmail.mc to relay mail using  AUTH-SMTP. Created users into the sasldb2.
The mail server is behind a firewall.
When I try to send mail to the server for relaying from the internet I get an error
relaying is denied.
         
[root@oldguard log]# sendmail -O LogLevel=14 -bs -Am
220 mydomain.com ESMTP Sendmail 8.12.8/8.12.8; Mon, 5 Apr 2004 01:10:37  +0800          
ehlo localhost                                                                  
250-mydomain.com Hello root@localhost, pleased to meet you                      
250-ENHANCEDSTATUSCODES                                                        
250-PIPELINING                                                                  
250-8BITMIME                                                                    
250-SIZE                                                                        
250-DSN                                                                        
250-ETRN                                                                        
250-AUTH DIGEST-MD5 CRAM-MD5                                                    
250-DELIVERBY                                                                  
250 HELP                                                                        
                                                                               
and the content of the maillog from /var/log/maillog
Apr  5 01:10:37 sasco sendmail[13133]: NOQUEUE: connect from root@localhost    
Apr  5 01:10:37 sasco sendmail[13133]: STARTTLS: ServerCertFile missing        
Apr  5 01:10:37 sasco sendmail[13133]: AUTH: available mech=DIGEST-MD5 CRAM-MD5
ANONYMOUS, allowed mech=GSSAPI DIGEST-MD5 CRAM-MD5 LOGIN PLAIN                  
Apr  5 01:10:37 sasco sendmail[13133]: i34HAbFF013133: Milter: no active filter
Apr  5 01:10:51 sasco sendmail[13133]: i34HAbFF013133: root@localhost did not is
sue MAIL/EXPN/VRFY/ETRN during connection to stdin                              

Any help and pointers would be apprecaited.

Rgds
Atma
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Question by:asidu
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19 Comments
 
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by:jlevie
ID: 10754591
Outlook can only use LOGIN as an authentication method and your sendmail config is not offering that. My guess is that your sendmail.mc contains:

define(`confAUTH_OPTIONS', `A p')dnl

which only offers LOGIN if the connection is encrypted. Changing that to:

define(`confAUTH_OPTIONS', `A')dnl

will offer LOGIN and PLAIN and your Outlook client will be able to authenticate and then relay through the server.

The only POP (or IMAP) implementation that I know of that uses SASL is the Cyrus IMAP implementation (http://asg.web.cmu.edu/cyrus/).
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by:asidu
ID: 10756672
hi
I changed   define(`confAUTH_OPTIONS', `A p')dnl
to   define(`confAUTH_OPTIONS', `A')dnl
then did m4 conversion and restarted the sendmail service.
Also changed the password for a test1 accout for unix, salsdb and salsdb2.

Is there any difference between the two commands
saslpasswd -c test1
saslpasswd2 -c test1
 
Tried sending mail from Eudora and Outlook from remote....both clients are not able to send the mail
out via my sendmail box.

The error message in the /var/log/maillog is
Apr  5 19:37:59 sasco sendmail[14795]: i35BbSpo014795: ruleset=check_rcpt, arg1=<test_atma@singtel.com>, relay= [202.166.12.4], reject=550 5.7.1 <test_atma@singtel.com>... Relaying denied. Proper authentication required.

However, take note that I can send mail from remote mail clients to mydomain.
If I add the remote address to the access file and allow relay the mails are sent off smoothly.
Obvioulsy that is not the right solution.

[root@oldguard mail]# more access
# Check the /usr/share/doc/sendmail/README.cf file for a description
# of the format of this file. (search for access_db in that file)
# The /usr/share/doc/sendmail/README.cf is part of the sendmail-doc
# package.
#
# by default we allow relaying from localhost...
localhost.localdomain           RELAY
localhost                       RELAY
127.0.0.1                       RELAY

Also my sendmial.mc file is as follows.

define(`confDEF_USER_ID',``8:12'')dnl
define(`confTRUSTED_USER', `smmsp')dnl
dnl define(`confAUTO_REBUILD')dnl
define(`confTO_CONNECT', `1m')dnl
define(`confTRY_NULL_MX_LIST',true)dnl
define(`confDONT_PROBE_INTERFACES',true)dnl
define(`PROCMAIL_MAILER_PATH',`/usr/bin/procmail')dnl
define(`ALIAS_FILE', `/etc/aliases')dnl
dnl define(`STATUS_FILE', `/etc/mail/statistics')dnl
define(`UUCP_MAILER_MAX', `2000000')dnl
define(`confUSERDB_SPEC', `/etc/mail/userdb.db')dnl
define(`confPRIVACY_FLAGS', `authwarnings,novrfy,noexpn,restrictqrun')dnl
define(`confDEF_AUTH_INFO', `/etc/mail/default-auth-info')dnl
define(`confAUTH_OPTIONS', `A')dnl
dnl #
dnl # The following allows relaying if the user authenticates, and disallows
dnl # plaintext authentication (PLAIN/LOGIN) on non-TLS links
dnl #
dnl define(`confAUTH_OPTIONS', `A p')dnl
dnl #
dnl # PLAIN is the preferred plaintext authentication method and used by
dnl # Mozilla Mail and Evolution, though Outlook Express and other MUAs do
dnl # use LOGIN. Other mechanisms should be used if the connection is not
dnl # guaranteed secure.
dnl #
TRUST_AUTH_MECH(`DIGEST-MD5 CRAM-MD5 LOGIN PLAIN')dnl
define(`confAUTH_MECHANISMS', `GSSAPI DIGEST-MD5 CRAM-MD5 LOGIN PLAIN')dnl
dnl #
dnl #
dnl # Rudimentary information on creating certificates for sendmail TLS:
dnl #     make -C /usr/share/ssl/certs usage
dnl #
dnl define(`confCACERT_PATH',`/usr/share/ssl/certs')
dnl define(`confCACERT',`/usr/share/ssl/certs/ca-bundle.crt')
dnl define(`confSERVER_CERT',`/usr/share/ssl/certs/sendmail.pem')
dnl define(`confSERVER_KEY',`/usr/share/ssl/certs/sendmail.pem')
dnl #
dnl # This allows sendmail to use a keyfile that is shared with OpenLDAP's
dnl # slapd, which requires the file to be readble by group ldap
dnl #
dnl define(`confDONT_BLAME_SENDMAIL',`groupreadablekeyfile')dnl
dnl #
dnl define(`confTO_QUEUEWARN', `6h')dnl
dnl define(`confTO_QUEUERETURN', `3d')dnl
dnl define(`confQUEUE_LA', `12')dnl
dnl define(`confREFUSE_LA', `18')dnl
define(`confTO_IDENT', `0')dnl
dnl FEATURE(delay_checks)dnl
FEATURE(`no_default_msa',`dnl')dnl
FEATURE(`smrsh',`/usr/sbin/smrsh')dnl
FEATURE(`mailertable',`hash -o /etc/mail/mailertable.db')dnl
FEATURE(`virtusertable',`hash -o /etc/mail/virtusertable.db')dnl
FEATURE(redirect)dnl
FEATURE(always_add_domain)dnl
FEATURE(use_cw_file)dnl
FEATURE(use_ct_file)dnl
nl #
dnl FEATURE(`accept_unresolvable_domains')dnl
dnl #
dnl FEATURE(`relay_based_on_MX')dnl
dnl #
dnl # Also accept email sent to "localhost.localdomain" as local email.
dnl #
LOCAL_DOMAIN(`localhost.localdomain')dnl
dnl #
dnl # The following example makes mail from this host and any additional
dnl # specified domains appear to be sent from mydomain.com
dnl #
dnl MASQUERADE_AS(`mydomain.com')dnl
dnl #
dnl # masquerade not just the headers, but the envelope as well
dnl #
dnl FEATURE(masquerade_envelope)dnl
dnl #
dnl # masquerade not just @mydomainalias.com, but @*.mydomainalias.com as well
dnl #
dnl FEATURE(masquerade_entire_domain)dnl
dnl #
dnl MASQUERADE_DOMAIN(localhost)dnl
dnl MASQUERADE_DOMAIN(localhost.localdomain)dnl
dnl MASQUERADE_DOMAIN(mydomainalias.com)dnl
dnl MASQUERADE_DOMAIN(mydomain.lan)dnl
MAILER(smtp)dnl
MAILER(procmail)dnl

My main objective here is to make sure that SMTP-AUTH works right.
I have been testing around the sendmail.mc, access,  sasl and SATRTTLS..could some thing have gone wrong ?

Looking forward for your response.

Thanks
Atma
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by:jlevie
ID: 10760497
Sendmail 8.12 on RedHat 9 will only use SASL2, so you don't need /etc/sasldb and don't need to use saspasswd or sasldblistuser. The correct utilities as saslpasswd2 & sasldblistusers2. To use /etc/sasldb2 for authentication you need for /usr/lib/sasl2/Sendmail.conf contain:

pwcheck_method:auxprop

and restart sendmail. Your sendmail.mc looks fine to me. My guess is that SMTP AUTH isn't working because /usr/lib/sasl2/Sendmail.conf probably still contains "pwcheck_method:saslauthd".
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by:asidu
ID: 10762696
Hi, Thanks,
[root@oldguard sasl]# more Sendmail.conf
pwcheck_method:auxprop
[root@oldguard sasl]# more smtpd.conf
pwcheck_method: sasldb

That are the contents of the two files in /usr/lib/sasl/

Not sure of the second one.

But the SMTP AUTH is still not working.

Atma
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by:jlevie
ID: 10762796
Sendmil only uses Sendmail.conf and I think Postfix might use smtp.conf. Since the sendmail method is auxprop the user must be shown in the output of sasldblistusers2 and the hostname at the time sendmail started (from sendmail's point of view must match what's hown in that output. For example on my mail server, which supports SMTP AUTH I have:

/etc/hosts:
127.0.0.1       localhost.localdomain localhost
10.1.0.254      praetorian.entrophy-free.net praetorian

/etc/sysconfig/network:
NETWORKING=yes
HOSTNAME=praetorian.entrophy-free.net

/usr/lib/sasl2/Sendmail.conf:
pwcheck_method:auxprop

and 'ifconfig eth0' shows:
eth0      Link encap:Ethernet  HWaddr 00:50:04:82:6E:80
          inet addr:10.1.0.254  Bcast:10.1.0.255  Mask:255.255.255.0
...

Executing sasldblistusers2 I see:
...
jim@praetorian.entrophy-free.net: userPassword
...

My mail client is configured to do SMTP authentication and the user name I set on that client is jim
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by:asidu
ID: 10762927
Jim Thanks,

I checked all the info that you posted in the last mail. Mine is similar to yours.
How to reintialize the sasldblistusers and sasldblistusers2 ?
i am not able to delet the users from the database.

I have the out put for sasldblistusers and sasldblisusers2 below.
[root@oldguard log]# sasldblistusers
user: test2 realm: oldguard mech: PLAIN
user: test1 realm: oldguard mech: PLAIN
user: test2 realm: oldguard mech: DIGEST-MD5
user: test2 realm: oldguard mech: CRAM-MD5
user: test1 realm: oldguard mech: CRAM-MD5
user: atma realm: oldguard mech: CRAM-MD5
user: atma realm: oldguard mech: PLAIN
user: test1 realm: oldguard mech: DIGEST-MD5
user: atma realm: oldguard mech: DIGEST-MD5
[root@oldguard log]# sasldblistusers2
helpdesk@oldguard: userPassword
test@oldguard: userPassword
atma@oldguard: userPassword
test1@oldguard: userPassword

Could you please verify the contents of the files with yours. Any issue ?

Thanks
Atma
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by:jlevie
ID: 10763123
Just delete /etc/sasldb as Sendmail won't use it. I think your problem lies in the user@oldguard entries in the output of sasldblistusers2. You server isn't configured with a Fully Qualified Domain Name (FQDN) as it should be for correct operation. Typically, the FQDN of the server on the inside of the firewall should be the same name as it is known on the outside. Sendmail, and quite a few other things, really need to see the hostname of the server they are running on have an FQDN, e.g., srv-name.domain.tld.

Deleting an entry from sasldb2 is pretty easy, like 'saspasswd -d test@oldguard: userPassword
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Author Comment

by:asidu
ID: 10763295
Jim,
Yes, I did that removed off the sasldb and sasldb2.
Created the new sasldb2 for test1 account using salduserspasswd2 -c test1
The server is situated behind a firewall,  I have changed the hostname oldguard as it
appears it in the DNS server.


restarted the saslauthd
[root@oldguard etc]# ps -aux|grep sas
root      3774  0.2  0.1  2200  624 ?        S    13:43   0:00 /usr/sbin/saslauthd -m /var/run/saslauthd/mux -a shadow
root      3782  0.0  0.1  3524  536 pts/1    R    13:43   0:00 grep sas

[root@oldguard etc]# sasldblistusers2
testonly@oldguard.tassco.org.sg: userPassword

The issue remains.
Is there a way to test out the SMTP-AUTH from a command level. At the moment I am
still not very certain if the AUTH mechanism is working fine...or could it be a network related issue.

Thanks.
Atma
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LVL 12

Author Comment

by:asidu
ID: 10764955
Sorry some typo error...
Created the new sasldb2 for test1 account using salduserspasswd2 -c test1

it shoud read as
Created the new sasldb2 for testonly account using saslpasswd2 -c testonly

Atma
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by:jlevie
ID: 10769652
> Is there a way to test out the SMTP-AUTH from a command level.

Not that I know of. Starting up sendmail and including "-X some-log" will show each step of mail transactions, inculding the authentication info (base64 encoded). That can be decoded and the username, realm, and passowrd can be seen. Examples of decoding this can be seen at http://sendmail.org/~ca/email/authrealms.html#authexamples
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by:asidu
ID: 10771404
Could you confirm the version of sendmail that you are using.
The copy running on my machine now is sendmail-8.12.8 on redhat 9
Is it same as yours.
Thank you.

Atma
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by:jlevie
ID: 10771545
Well, at present I'm running RHEL 3.0ES and it has Sendmail 8.12.10, but I've used SMTP_AUTH on RH 8.0 & 9.
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by:asidu
ID: 10775306
Jim

 I read the notes and tried to figure out
what is wrong. Sadly not able to find the error. Debug info is point to an
error during authetication. I tried many methods to input the password.
With the realms but not able to be autheticated.
Your comments apprecaited.
Atma

Debug details :

[root@oldguard sasl]# sendmail -O LogLevel=14 -bd -X /tmp/output.log          
[root@oldguard sasl]# ps -aux | grep send                                    
root      8843  0.0  0.7  5920 2492 ?        S    22:19   0:00 [sendmail]    
root      8849  0.0  0.1  3568  624 pts/0    S    22:20   0:00 grep send      

[root@oldguard sasl]# more /usr/lib/sasl/Sendmail.conf                                      
pwcheck_method:auxprop                                                        

telnet session on port 25
[root@oldguard sasl]# telnet localhost 25                                      
Trying 127.0.0.1...                                                            
Connected to localhost.                                                        
Escape character is '^]'.                                                      
220 oldguard.sasco.org.sg ESMTP Sendmail 8.12.8/8.12.8; Wed, 7 Apr 2004 22:27:35
 +0800                                                                          
ehlo local                                                                      
250-oldguard.sasco.org.sg Hello localhost.localdomain [127.0.0.1], pleased to me
et you                                                                          
250-ENHANCEDSTATUSCODES                                                        
250-PIPELINING                                                                  
250-8BITMIME                                                                    
250-SIZE                                                                        
250-DSN                                                                        
250-ETRN                                                                        
250-AUTH LOGIN PLAIN                                                            
250-DELIVERBY                                                                  
250 HELP                                                                        
AUTH LOGIN                                          
334 VXNlcm5hbWU6                                    
john                                                
334 UGFzc3dvcmQ6                                    
john                                                
535 5.7.0 authentication failed                    
AUTH LOGIN                                          
334 VXNlcm5hbWU6                                    
test1                                              
334 UGFzc3dvcmQ6                                    
test1                                              
535 5.7.0 authentication failed                    
QUIT                                                
221 2.0.0 oldguard.sasco.org.sg closing connection  
Connection closed by foreign host.                  

users registerd :
[root@oldguard sasl]# sasldblistusers2    
test1@oldguard.sasco.org.sg: userPassword
john@sasco.org.sg: userPassword          


output in /var/log/maillog

Apr  7 22:19:55 oldguard sendmail[8843]: starting daemon (8.12.8): SMTP        
Apr  7 22:19:55 oldguard sendmail[8843]: STARTTLS: ServerCertFile missing      
Apr  7 22:19:55 oldguard sendmail[8843]: started as: sendmail -O LogLevel=14 -bd
 -X /tmp/output.log                                                            
Apr  7 22:25:54 oldguard sendmail[8856]: NOQUEUE: connect from localhost.localdo
main [127.0.0.1]                                                                
Apr  7 22:25:54 oldguard sendmail[8856]: AUTH: available mech=PLAIN LOGIN ANONYM
OUS, allowed mech=GSSAPI DIGEST-MD5 CRAM-MD5 LOGIN PLAIN                        
Apr  7 22:25:54 oldguard sendmail[8856]: i37EPstY008856: Milter: no active filte
r                                                                              
Apr  7 22:26:42 oldguard sendmail[8856]: i37EPstY008856: AUTH failure (LOGIN): n
o mechanism available (-4)                                                      
Apr  7 22:27:09 oldguard sendmail[8856]: i37EPstY008856: localhost.localdomain [
127.0.0.1] did not issue MAIL/EXPN/VRFY/ETRN during connection to MTA          
Apr  7 22:27:35 oldguard sendmail[8858]: NOQUEUE: connect from localhost.localdo
Apr  7 22:27:35 oldguard sendmail[8858]: NOQUEUE: connect from localhost.localdo
main [127.0.0.1]                                                                
Apr  7 22:27:35 oldguard sendmail[8858]: AUTH: available mech=PLAIN LOGIN ANONYM
OUS, allowed mech=GSSAPI DIGEST-MD5 CRAM-MD5 LOGIN PLAIN                        
Apr  7 22:27:35 oldguard sendmail[8858]: i37ERZtY008858: Milter: no active filter                                                    
Apr  7 22:29:17 oldguard sendmail[8858]: i37ERZtY008858: AUTH failure (LOGIN): n
o mechanism available (-4)                                                      
Apr  7 22:29:33 oldguard sendmail[8858]: i37ERZtY008858: AUTH failure (LOGIN): n
o mechanism available (-4)                                                      
Apr  7 22:29:46 oldguard sendmail[8858]: i37ERZtY008858: localhost.localdomain [
127.0.0.1] did not issue MAIL/EXPN/VRFY/ETRN during connection to MTA          


08858 >>> 220 oldguard.sasco.org.sg ESMTP Sendmail 8.12.8/8.12.8; Wed, 7 Apr 200
4 22:27:35 +0800                                                                
08858 <<< ehlo local                                                            
08858 >>> 250-oldguard.sasco.org.sg Hello localhost.localdomain [127.0.0.1], ple
ased to meet you                                                                
08858 >>> 250-ENHANCEDSTATUSCODES                                              
08858 >>> 250-PIPELINING                                                        
08858 >>> 250-8BITMIME                                                          
08858 >>> 250-SIZE                                                              
08858 >>> 250-DSN                                                              
08858 >>> 250-ETRN                                                              
08858 >>> 250-AUTH LOGIN PLAIN                                                  
08858 >>> 250-DELIVERBY                                                        
08858 >>> 250 HELP                                                              
08858 <<< AUTH LOGIN                                                            
08858 >>> 334 VXNlcm5hbWU6                                                      
08858 <<< john                                                                    
08858 >>> 334 UGFzc3dvcmQ6                                      
08858 <<< john                                                  
08858 >>> 535 5.7.0 authentication failed                        
08858 <<< AUTH LOGIN                                            
08858 >>> 334 VXNlcm5hbWU6                                      
08858 <<< test1                                                  
08858 >>> 334 UGFzc3dvcmQ6                                      
08858 <<< test1                                                  
08858 >>> 535 5.7.0 authentication failed                        
08858 <<< QUIT                                                  
08858 >>> 221 2.0.0 oldguard.sasco.org.sg closing connection    
                                                 

0
 
LVL 12

Author Comment

by:asidu
ID: 10792299
Jim,
I get a presistent error inthe log. Milter:no acitve filter. It looks like neither Eudora nor Outlook is able to autheitcate. Both the client issur HELO instead off EHLO.
Any idea what shuold I do ?
I also made error in my earlier test when doing the telnet 127.0.0.1 25,
at AUTH LOGIN I used plain text which resulted in failed Authentication,
How can I get the right user ID and passwd. Any pointer would be appreciated.

Atma



 maillog:

Apr  9 23:42:35 oldguard sendmail[14311]: i39FgZBd014311: Milter: no active filter
Apr  9 23:42:35 oldguard sendmail[14311]: i39FgZBd014311: --- 220 oldguard.sasco.org.sg ESMTP Sendmail 8.12.8/8.12.8; Fri, 9 Apr 2004 23:42:35 +0800
Apr  9 23:42:35 oldguard sendmail[14311]: i39FgZBd014311: <-- XXXX mastana.oldguard.sasco.org.sg
Apr  9 23:42:35 oldguard sendmail[14311]: i39FgZBd014311: --- 500 5.5.1 Command unrecognized: "XXXX mastana.oldguard.sasco.org.sg"
Apr  9 23:42:35 oldguard sendmail[14311]: i39FgZBd014311: <-- HELO mastana.oldguard.sasco.org.sg
Apr  9 23:42:35 oldguard sendmail[14311]: i39FgZBd014311: --- 250 oldguard.sasco.org.sg Hello bb-203-125-19-237.singnet.com.sg [203.125.19.237], pleased to meet you
Apr  9 23:42:36 oldguard sendmail[14311]: i39FgZBd014311: <-- RSET
Apr  9 23:42:36 oldguard sendmail[14311]: i39FgZBd014311: --- 250 2.0.0 Reset state
Apr  9 23:42:36 oldguard sendmail[14311]: i39FgZBe014311: <-- MAIL FROM:<test1@oldguard.sasco.org.sg>
0
 
LVL 40

Accepted Solution

by:
jlevie earned 250 total points
ID: 10801272
From what I can see, the test1 account and the server config are now consistant and SNTP AUTH should work. From the maillog in the last comment it looks like AUTH wasn't tried because the mail server allowed the connection as a result of an access map or DNS lookup provision.  To tell if AUTH worked with that client it would be necessary test from a client whose relayed message is known to fail without AUTH.

Trying to test authentication to SMTP can't be done on the command line when telneting to the mail server. You can't simply enter the login name and password. That data and some other stuff must be in a bas64 encoded packet set to the Sendmail server. See  http://sendmail.org/~ca/email/authrealms.html#authexamples for examples of that exchange.
0
 
LVL 12

Author Comment

by:asidu
ID: 11280062
The administrator,

This question is not resolved. I would like to close it.
The problem has been narrowed to an intermeidate firewall.
Liike to award 250 points to jlevie for his assistance.

Asidu
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