assinging external email address to user in linux (and working via sendmail)

I have sendmail working on my linux server, and it is now able to relay emails to my Exchange server.

On the Linux server, users are pulled from LDAP. They have a coresponding external email address that is setup in LDAP. I would like it so that if a user is refered to with sendmail:

ie. echo test | mailx -s "this is a test" jsmith

That instead of the email being delivered locally to the server, it will instead go to jsmith@outsidedomain.com and will be relayed through the mail server that is already configured through sendmail.
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ryan80Asked:
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meko72Commented:
ryan80Author Commented:
well i want to use aliasses for the users, but I want the information to be pulled from LDAP. Its the LDAP integration that I am missing.
upanwarCommented:
You can configure email alias for the same in /etc/aliases.

# vi /etc/aliases

Append / change an email alias in this format
alias_name:   email_id1

E.g

jsmith:   jsmith@outsidedomain.com

Save and exit the alias file

5.Execute the newaliases command followed by echo $? (suppose there is no error found, you will get a 0 returned by the echo command).

Alternatively, you can execute the equivalent sendmail -bi command (since this is a Sendmail system)


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ryan80Author Commented:
but is there a way to have it pull the aliases from the LDAP mail variable? LDAP is already configured and it would be nice to only have one location to maintain the records, and not have to edit the aliases file on all of the servers.
upanwarCommented:
I haven't configured aliased in LDAP but I have found something for you. It may help you.

http://www.sendmail.org/m4/ldap.html

http://www.aixmind.com/?tag=sendmail
jar3817Commented:
Maybe not. How is sendmail setup on your server to interface with ldap? Are you talking about your active directory or some other ldap server?
ryan80Author Commented:
it is a stand alone ldap server. it does not interact with AD at all. Under LDAP there is an attribute named mail that has the email address that I would like the emails sent to.

@upanwar: I was looking at those pages. I believe that the contain the configuration information, but unfortunately, I am not familiar enough to know how to cutomize it for my LDAP setup. I dont think mine is customized at all, so there are probably just a few minor changes that I will need.



ryan80Author Commented:
here is a sample entry from ldap of your average user:

 jsmith, People, internal.zais.com
dn: uid=jsmith,ou=People, dc=internal, dc=domain, dc=com
objectClass: posixAccount
objectClass: top
objectClass: person
objectClass: organizationalPerson
objectClass: inetOrgPerson
objectClass: shadowAccount
uid: jsmith
cn: Joe Smith
uidNumber: 524
gidNumber: 500
homeDirectory: /home/jsmith
loginShell: /bin/bash
gecos: Joe Smith
sn: Smith
givenName: Joe
mail: joe.smith@exchangedomain.com
shadowLastChange: 14468
shadowMax: 99999
shadowWarning: 7




I am not sure what command to put after ldap:

maybe
-k (&(objectClass=person)(mail=%0)) -v mgrpRFC822MailMember  ???
jar3817Commented:
ok, but how is this ldap server integrated into sendmail?
ryan80Author Commented:
from what I have read:

If you prefer not to use the default LDAP schema for your aliases, you can specify the map parameters when setting ALIAS_FILE. For example:

define(`ALIAS_FILE', `ldap:-k (&(objectClass=mailGroup)(mail=%0)) -v mgrpRFC822MailMember')

so I guess that it does a search of the recipient, and compares it to ldap and pulls a value? I want it to pull the "mail" value, but I am not sure what the -k and -v specify.
jar3817Commented:
Can you post your /etc/mail/sendmail.mc file?
upanwarCommented:
As per my understanding here -k to map the ldap object and -v for value of that object.


Here's an example of an ldapsearch and the output of one alias entry:
# ldapsearch -h reptilebso -b cn=aixdata -s sub "(&(objectClass=mailGroup)(mail=*))"
mail=tuvo1,ou=aliases,cn=aixdata
mail=tuvo1
cn=tuvo1
objectClass=mailGroup
objectClass=top
mgrpRFC822MailMember=mrtuvo@gmail.com

In the above alias entry, "tuvo1" is aliased to "mrtuvo@gmail.com".
I.e. when you mail to tuvo1, it will be sent to "mrtuvo@gmail.com".

O AliasFile=/etc/mail/aliases,ldap:-k (&(objectClass=mailGroup)(mail=%0)) -v mgrpRFC822MailMember -h reptilebso -b "ou=aliases,cn=aixdata"

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ryan80Author Commented:
the line in question is

define(`ALIAS_FILE', `ldap:-k(&(objectClass=person)(mail=%0)) -v rfc822MailMember')dnl
divert(-1)dnl
dnl #
dnl # This is the sendmail macro config file for m4. If you make changes to
dnl # /etc/mail/sendmail.mc, you will need to regenerate the
dnl # /etc/mail/sendmail.cf file by confirming that the sendmail-cf package is
dnl # installed and then performing a
dnl #
dnl #     make -C /etc/mail
dnl #
include(`/usr/share/sendmail-cf/m4/cf.m4')dnl
VERSIONID(`setup for linux')dnl
OSTYPE(`linux')dnl
dnl #
dnl # Do not advertize sendmail version.
dnl #
dnl define(`confSMTP_LOGIN_MSG', `$j Sendmail; $b')dnl
dnl #
dnl # default logging level is 9, you might want to set it higher to
dnl # debug the configuration
dnl #
dnl define(`confLOG_LEVEL', `9')dnl
dnl #
dnl # Uncomment and edit the following line if your outgoing mail needs to
dnl # be sent out through an external mail server:
dnl #
define(`SMART_HOST', `[10.1.1.36]')dnl
dnl #
define(`confDEF_USER_ID', ``8:12'')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', `ldap:-k(&(objectClass=person)(mail=%0)) -v rfc822MailMember')dnl
define(`STATUS_FILE', `/var/log/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(`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 # Please remember that saslauthd needs to be running for AUTH. 
dnl #
dnl TRUST_AUTH_MECH(`EXTERNAL DIGEST-MD5 CRAM-MD5 LOGIN PLAIN')dnl
dnl define(`confAUTH_MECHANISMS', `EXTERNAL GSSAPI DIGEST-MD5 CRAM-MD5 LOGIN PLAIN')dnl
dnl #
dnl # Rudimentary information on creating certificates for sendmail TLS:
dnl #     cd /etc/pki/tls/certs; make sendmail.pem
dnl # Complete usage:
dnl #     make -C /etc/pki/tls/certs usage
dnl #
dnl define(`confCACERT_PATH', `/etc/pki/tls/certs')dnl
dnl define(`confCACERT', `/etc/pki/tls/certs/ca-bundle.crt')dnl
dnl define(`confSERVER_CERT', `/etc/pki/tls/certs/sendmail.pem')dnl
dnl define(`confSERVER_KEY', `/etc/pki/tls/certs/sendmail.pem')dnl
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', `4h')dnl
dnl define(`confTO_QUEUERETURN', `5d')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
dnl #
dnl # The following limits the number of processes sendmail can fork to accept 
dnl # incoming messages or process its message queues to 20.) sendmail refuses 
dnl # to accept connections once it has reached its quota of child processes.
dnl #
dnl define(`confMAX_DAEMON_CHILDREN', `20')dnl
dnl #
dnl # Limits the number of new connections per second. This caps the overhead 
dnl # incurred due to forking new sendmail processes. May be useful against 
dnl # DoS attacks or barrages of spam. (As mentioned below, a per-IP address 
dnl # limit would be useful but is not available as an option at this writing.)
dnl #
dnl define(`confCONNECTION_RATE_THROTTLE', `3')dnl
dnl #
dnl # The -t option will retry delivery if e.g. the user runs over his quota.
dnl #
FEATURE(local_procmail, `', `procmail -t -Y -a $h -d $u')dnl
FEATURE(`access_db', `hash -T<TMPF> -o /etc/mail/access.db')dnl
FEATURE(`blacklist_recipients')dnl
EXPOSED_USER(`root')dnl
dnl #
dnl # For using Cyrus-IMAPd as POP3/IMAP server through LMTP delivery uncomment
dnl # the following 2 definitions and activate below in the MAILER section the
dnl # cyrusv2 mailer.
dnl #
dnl define(`confLOCAL_MAILER', `cyrusv2')dnl
dnl define(`CYRUSV2_MAILER_ARGS', `FILE /var/lib/imap/socket/lmtp')dnl
dnl #
dnl # The following causes sendmail to only listen on the IPv4 loopback address
dnl # 127.0.0.1 and not on any other network devices. Remove the loopback
dnl # address restriction to accept email from the internet or intranet.
dnl #
DAEMON_OPTIONS(`Port=smtp,Addr=127.0.0.1, Name=MTA')dnl
dnl #
dnl # The following causes sendmail to additionally listen to port 587 for
dnl # mail from MUAs that authenticate. Roaming users who can't reach their
dnl # preferred sendmail daemon due to port 25 being blocked or redirected find
dnl # this useful.
dnl #
dnl DAEMON_OPTIONS(`Port=submission, Name=MSA, M=Ea')dnl
dnl #
dnl # The following causes sendmail to additionally listen to port 465, but
dnl # starting immediately in TLS mode upon connecting. Port 25 or 587 followed
dnl # by STARTTLS is preferred, but roaming clients using Outlook Express can't
dnl # do STARTTLS on ports other than 25. Mozilla Mail can ONLY use STARTTLS
dnl # and doesn't support the deprecated smtps; Evolution <1.1.1 uses smtps
dnl # when SSL is enabled-- STARTTLS support is available in version 1.1.1.
dnl #
dnl # For this to work your OpenSSL certificates must be configured.
dnl #
dnl DAEMON_OPTIONS(`Port=smtps, Name=TLSMTA, M=s')dnl
dnl #
dnl # The following causes sendmail to additionally listen on the IPv6 loopback
dnl # device. Remove the loopback address restriction listen to the network.
dnl #
dnl DAEMON_OPTIONS(`port=smtp,Addr=::1, Name=MTA-v6, Family=inet6')dnl
dnl #
dnl # enable both ipv6 and ipv4 in sendmail:
dnl #
dnl DAEMON_OPTIONS(`Name=MTA-v4, Family=inet, Name=MTA-v6, Family=inet6')
dnl #
dnl # We strongly recommend not accepting unresolvable domains if you want to
dnl # protect yourself from spam. However, the laptop and users on computers
dnl # that do not have 24x7 DNS do need this.
dnl #
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 #
MASQUERADE_AS('server.linux.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 #
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
dnl MAILER(cyrusv2)dnl

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ryan80Author Commented:
so basically i want it to match the uid and then return the mail attribute value.
upanwarCommented:
I think so.
ryan80Author Commented:
ok so then this should work?

-k (&(objectClass=person)(uid=%0)) -v mail

and it will match the uid and then return the value that mail is set to.
ryan80Author Commented:
awsome, that worked.
upanwarCommented:
:)
upanwarCommented:
Congratilations.... :)
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