Inhaltsverzeichnis

Sendmail

eine kurze Einführung in Sendmail (FreeBSD 4.7)

Allgemeine Steuerung von Sendmail

# cd /etc/mail                        # in das Verzeichnis wechseln
# make                                # alle Konfig-Dateien und Datenbanken neu schreiben
# make stop                           # Sendmail stopen
# make start                          # Sendmail starten
# make restart                        # Sendmail neu starten
# ls -l /var/mail/                    # User-spezifische Dateien
# ls -l /var/log/maillog              # Mail-Logdatei
# ls -l /var/log/messages             # System-Logdatei mit Sendmailmeldungen

FreeBSD

# vi /etc/rc.conf

Sendmail ist komplett abgeschaltet:

sendmail_enable="NONE"

Damit E-Mails nur von "localhost" angenommen werden koennen:

sendmail_enable="NO"

Damit E-Mails auch von anderen Rechnern angenommen werden koennen:

sendmail_enable="YES"

Linux

Sendmail zum empfangen von E-Mails konfigurieren

# vi /etc/mail/sendmail.mc            # ALT
# vi /etc/mail/freebsd.mc             # NEU

Sendmail lauscht nur auf "localhost":

DAEMON_OPTIONS(`Port=smtp, Addr=127.0.0.1, Name=MTA')dnl

oder

Sendmail lauscht nur auf "192.168.0.1":

DAEMON_OPTIONS(`Port=smtp, Addr=192.168.0.1, Name=MTA')dnl

oder

Sendmail lauscht auf "localhost" und "192.168.0.1":

DAEMON_OPTIONS(`Port=smtp, Addr=127.0.0.1, Name=MTA')dnl
DAEMON_OPTIONS(`Port=smtp, Addr=192.168.0.1, Name=MTA')dnl

oder

Sendmail lauscht auf allen IP-Adressen:

DAEMON_OPTIONS(`Port=smtp, Name=MTA')dnl

Die Datei "/etc/mail/freebsd.mc" wird nach dem ersten 'make' in `hostname`.mc (z.B.: /etc/mail/mail.mydomain.de.mc) umbenannt, weitere Aenderungen sollten dann in der Datei vorgenommen werden.

Diese "Addr"-Option wird von FreeBSD ignoriert, diese Einstellung wird mit "YES/NO/NONE" in der "/etc/rc.conf" vorgenommen!

Konfiguration Beginn

um sich die Statusmeldungen des Systems zuschicken zu lassen

# vi /etc/mail/aliases
[adressierter Empfänger]      	[ausgehende Adresse oder lokale User]
sshd:					meine@mailadresse.de
root:					admin@mailadresse.de,sysop@mailadresse.de
webmaster:				fritz

den neuen Eintrag aktivieren

# newaliases

auf diese Domains soll Sendmail reagieren (MX'er)

# vi /etc/mail/sendmail.cw		# ALT
# vi /etc/mail/local-host-names	# NEU
maildomain.de

neue Konfiguration aktivieren

# cd /etc/mail ; make

hier werden die Zugriffe auf Weiterleitungen erlaubt oder verboten

# vi /etc/mail/access
cyberspammer.com                	550 We don't accept mail from spammers
FREE.STEALTH.MAILER@            	550 We don't accept mail from spammers
another.source.of.spam          	REJECT
okay.cyberspammer.com           	OK
127.0.0.1                       	RELAY
192.168.9.10                    	RELAY
192.168.0                       	RELAY

neue Konfiguration aktivieren

# cd /etc/mail ; make

OPTIONAL

hier werden Weiterleitungen zum mapen von Adressen eingetragen (Die Quell-Domainen in dieser Datei müssen auch in der "/etc/mail/local-host-names" bekannt gemacht werden!)

# vi /etc/mail/virtusertable

[eingehende Adresse]                  [ausgehende Adresse oder lokale User]
@maildomain.de			mailuser
webmaster@maildomain.de		adelheid
info@maildomain.de			news@new.de
@mail.de				mein@postfach.de

neue Konfiguration aktivieren

# cd /etc/mail ; make

Familien-Mailinglisten können hier z.B. wie folgt eingerichtet werden: (Die User "faeterlicherseits", "muetterlicherseits", "familie" brauchen im System, bei FreeBSD, nicht bekannt sein.)

# vi /etc/mail/virtusertable
faeterlicherseits@lokaldomain.de	faeterlicherseits
muetterlicherseits@lokaldomain.de	muetterlicherseits
familie@lokaldomain.de		familie
# vi /etc/mail/aliases

faeterlicherseits:			pa-oma@gmx.de,pa-opa@gmx.de,pa-tante@gmx.de,pa-onkel@gmx.de
muetterlicherseits:			ma-oma@gmx.de,ma-opa@gmx.de,ma-tante@gmx.de,ma-onkel@gmx.de
familie:				faeterlicherseits,muetterlicherseits,mama@gmx.de,papa@gmx.de
# vi /etc/mail/local-host-names

lokaldomain.de

neue Konfiguration aktivieren

# newaliases
# cd /etc/mail && make

Jetzt kann man mit nur einer E-Mail-Adresse an die ganze Familie schreiben und vergisst keinen:

# echo "Test" | mail -s TEST familie@lokaldomain.de

Konfiguration Ende

Jetzt einen MUA (z.B.: "qpopper" für den inetd oder "akpop3d" als Daemon) aus den Ports installieren, Anleitungen sind auch hier. (damit auf Port 110/pop3 gelauscht werden kann)

SENDMAIL INSTALLATION AND OPERATION GUIDE

Das grosse Handbuch fuer die aktuell installierte Sendmail-Version in FreeBSD 5.2.1-RC kann wie folgt generiert werden.

# cd /usr/src/contrib/sendmail/doc/op/
# make op.ps op.txt

"op.ps" ist die PostScript-Version, die mit

# ps2pdf op.ps op.pdf

in eine PDF-Version umgewandelt werden kann.

"op.txt" ist die plain Textdatei.

Absende-Adr. in Sendmail aendern (RedHat-Linux)

Masquerade the Envelope with Sendmail

We`re assuming a complete install of sendmail (this works with versions from 8.8.7 through 8.9.3).

as root:

# cd /usr/lib/sendmail-cf/cf/

Note: if you don`t have this directory and it doesn`t show up in an alternate path after you`ve searched for it then our assumptions about a full install are incorrect and you have to get everything installed prior to proceding! This would mean the sendmail-cf rpm as well as the sendmail rpm. I also recommend you install sendmail-doc.

# cp myconfig.mc /usr/lib/sendmail-cf/cf/myconfig.mc.bakup
# vi myconfig.mc

and insert the following text:

# /usr/lib/sendmail-cf/cf/redhat.mc plus the masquerade options 
divert(-1)dnl 
include(`../m4/cf.m4`)dnl 
define(`confDEF_USER_ID`,``8:12``)dnl 
define(`SMART_HOST`, `your.isps.mta`)dnl #added 
OSTYPE(`linux`)dnl
undefine(`UUCP_RELAY`)dnl 
undefine(`BITNET_RELAY`)dnl
FEATURE(redirect)dnl
FEATURE(always_add_domain)dnl 
FEATURE(use_cw_file)dnl
FEATURE(local_procmail)dnl 
FEATURE(nouucp)dnl
MAILER(procmail)dnl
MAILER(smtp)dnl
MASQUERADE_AS(yourdomain.dom)dnl            #added - use your domain name here! 
FEATURE(allmasquerade)dnl                   #added 
FEATURE(masquerade_envelope)dnl             #added 
HACK(check_mail3,`hash -a@JUNK /etc/mail/deny`)dnl 
HACK(use_ip,`/etc/mail/ip_allow`)dnl
HACK(use_names,`/etc/mail/name_allow`)dnl 
HACK(use_relayto,`/etc/mail/relay_allow`)dnl 
HACK(check_rcpt4)dnl 
HACK(check_relay3)dnl

If you`re using Red Hat all of this is in the original redhat.mc with a couple of lines added for folks in your situation….

The next issue in this process is that we have to have a legitimate (must have a DNS record) relay host to make this work so be sure and use your ISP`s MTA as a "smart" relay host. This would be inserted in place of "your.isps.mta" in the line which begins:

define(`SMART_HOST`... 

so if your ISP`s SMTP host was called "mail.yourisp.net" then your line would like this:

define(`SMART_HOST`, `mail.yourisp.net`) 

Now that we`ve created our myconfig.mc file we`ve got to create a new sendmail.cf… but how do we do that?

# mv /etc/sendmail.cf /etc/sendmail.cf.bakup 

(we`re still in the same directory with our new .mc file)

# m4 ../m4/cf.m4 myconfig.mc > nuconfig.cf 

Note: if there are any error messages here stop and let us know immediately.

# cp nuconfig.cf /etc/sendmail.cf 

Now we cd to /etc and edit the new sendmail.cf to ensure that our ISP`s MTA is still selected as our relay host. The line we`re looking for is:

"Smart" relay host (may be null)

DSmail.yourisp.net (where mail.yourisp.net would be the FQDN of your ISP`s MTA machine)

Next we want to issue the command

# /etc/rc.d/init.d/sendmail restart

double check the sendmail.cw and make sure your own domain is listed (i.e. yourdomain.dom) and we`re done!

Additional reading on this topic: Configuring sendmail for offline use by Simone Govoni

Eine sendmail.mc von RedHat 8.0

# vi /etc/mail/sendmail.mc
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 Red Hat Linux')dnl
OSTYPE(`linux')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 #
dnl define(`SMART_HOST',`smtp.your.provider')
dnl #
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(`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 #
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 #     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', `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 -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 # 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 # NOTE: binding both IPv4 and IPv6 daemon to the same port requires
dnl #       a kernel patch
dnl #
dnl DAEMON_OPTIONS(`port=smtp,Addr=::1, Name=MTA-v6, Family=inet6')dnl
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 #
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

um einen SMTP-Server aufzusetzen muss nur die folgende Zeile in eine entsprechende *.mc-Datei eingetragen werden:

dnl # DAEMON_OPTIONS(`Port=smtp,Addr=127.0.0.1, Name=MTA')dnl

So wird unter RedHat aus der "sendmail.mc" eine "sendmail.cf" generiert:

# m4 /etc/mail/sendmail.mc > /etc/sendmail.cf && service sendmail restart