[SuSE Linux] How to make Sendmail secure?
Hello. I'm currently running SuSe Linux 6.0, which I ham very happy with. But, I just noticed that it looks like the default setup of Sendmail allows for spam-relaying. What do I have to change to make sure it doesnt allow relaying? I hope someone can help me here.. ;) -- Eivind Olsen - eivindo@bgnett.no -- To get out of this list, please send email to majordomo@suse.com with this text in its body: unsubscribe suse-linux-e Check out the SuSE-FAQ at <A HREF="http://www.suse.com/Support/Doku/FAQ/"><A HREF="http://www.suse.com/Support/Doku/FAQ/</A">http://www.suse.com/Support/Doku/FAQ/</A</A>> and the archive at <A HREF="http://www.suse.com/Mailinglists/suse-linux-e/index.html"><A HREF="http://www.suse.com/Mailinglists/suse-linux-e/index.html</A">http://www.suse.com/Mailinglists/suse-linux-e/index.html</A</A>>
I think SuSE 6.0 comes with sendmail v8.8.8. If you are connected to the net you should consider getting v 8.9.3 which has alot of updated security features as well as anti-spam features. There is extensive documentation at www.sendmail.org. hawn Eivind Olsen writes:
Hello. I'm currently running SuSe Linux 6.0, which I ham very happy with. But, I just noticed that it looks like the default setup of Sendmail allows for spam-relaying. What do I have to change to make sure it doesnt allow relaying?
I hope someone can help me here.. ;)
-- Eivind Olsen - eivindo@bgnett.no
-- To get out of this list, please send email to majordomo@suse.com with this text in its body: unsubscribe suse-linux-e Check out the SuSE-FAQ at <A HREF="http://www.suse.com/Support/Doku/FAQ/"><A HREF="http://www.suse.com/Support/Doku/FAQ/</A">http://www.suse.com/Support/Doku/FAQ/</A</A>> and the archive at <A HREF="http://www.suse.com/Mailinglists/suse-linux-e/index.html"><A HREF="http://www.suse.com/Mailinglists/suse-linux-e/index.html</A">http://www.suse.com/Mailinglists/suse-linux-e/index.html</A</A>>
-- To get out of this list, please send email to majordomo@suse.com with this text in its body: unsubscribe suse-linux-e Check out the SuSE-FAQ at <A HREF="http://www.suse.com/Support/Doku/FAQ/"><A HREF="http://www.suse.com/Support/Doku/FAQ/</A">http://www.suse.com/Support/Doku/FAQ/</A</A>> and the archive at <A HREF="http://www.suse.com/Mailinglists/suse-linux-e/index.html"><A HREF="http://www.suse.com/Mailinglists/suse-linux-e/index.html</A">http://www.suse.com/Mailinglists/suse-linux-e/index.html</A</A>>
Shawn Clark <shawn@rbs.net> writes:
I think SuSE 6.0 comes with sendmail v8.8.8.
Which is the same version as shipped with 5.3. Other packages were upgraded for SuSe 6.0, so I wonder why sendmail was not? -- To get out of this list, please send email to majordomo@suse.com with this text in its body: unsubscribe suse-linux-e Check out the SuSE-FAQ at <A HREF="http://www.suse.com/Support/Doku/FAQ/"><A HREF="http://www.suse.com/Support/Doku/FAQ/</A">http://www.suse.com/Support/Doku/FAQ/</A</A>> and the archive at <A HREF="http://www.suse.com/Mailinglists/suse-linux-e/index.html"><A HREF="http://www.suse.com/Mailinglists/suse-linux-e/index.html</A">http://www.suse.com/Mailinglists/suse-linux-e/index.html</A</A>>
On Wed, 24 Mar 1999 00:35:23 -0800 (PST), Shawn wrote:
I think SuSE 6.0 comes with sendmail v8.8.8. If you are connected to the net you should consider getting v 8.9.3 which has alot of updated security features as well as anti-spam features. There is extensive documentation at www.sendmail.org.
shawn
Or the configuration files provide some help to enable the anti-spam features available for v8.8.8. An extract of my .mc file based on /etc/mail/linux.mc is set out below. To use it you have to amend rc.config to stop it rewriting sendmail.cf file and after creating your .mc file run the commands: /usr/bin/m4 /etc/mail/[whatever].mc > /etc/mail/sendmail.cf and (if it looks OK) cp /etc/mail/sendmail.cf /etc/sendmail.cf Relevant extracts are as follows: dnl Copyright (c) 1997-1998 S.u.S.E. GmbH Fuerth, Germany. dnl Author: Florian La Roche <florian@suse.de> dnl dnl dnl "dnl" starts a comment until the next newline charcter dnl putting words into `'-pairs disables macro expansion dnl include(`/usr/share/sendmail/m4/cf.m4') VERSIONID(`linux setup for SuSE - /etc/mail/celebrity.mc based on linux.mc')dnl OSTYPE(`linux')dnl --- a lot snipped --- dnl "use_ip" is a list of IP addresses that are allowed to relay mail. dnl "use_names" is a list of domain names that are allowed to relay mail. dnl If your host accepts non-local email as relay for other sites, use dnl "use_relayto" to specify those sites. dnl To ban unauthorized relay, you have to use one or more of "use_ip", dnl "use_names" and "use_relayto". Always add the line with "check_rcpt4". dnl HACK(`use_ip',`/etc/mail/LocalIP')dnl dnl HACK(`use_names', `/etc/mail/LocalNames')dnl dnl HACK(`use_relayto', `/etc/mail/RelayTo')dnl HACK(`check_rcpt4')dnl dnl dnl "check_rcpt5" can be used instead of "check_rcpt4" to also allow dnl email relay based on the envelope from address. The format of the file dnl is "user@address.domain allow" or "another.domain allow". dnl dnl HACK(`check_rcpt5', `hash -a@ALLOWED /etc/mail/allow.db')dnl dnl dnl ban local email delivery from well-known spam sites. dnl the format of the database file is: dnl junk.domain "Error-Code Error-Text" dnl spammer@address.domain "Error-Code Error-Text" dnl D.X.Y.Z "Error-Code Error-Text" dnl C.X.Y "Error-Code Error-Text" dnl B.X "Error-Code Error-Text" dnl A "Error-Code Error-Text" dnl junk.domain JUNK dnl spammer@address.domain SPAMMER dnl cyberpromo.com "571 Sorry, Spamford, no e-mail from your place." dnl honey@sweeties.com "571 Honey, you're a spammer, go away." dnl If the RHS is JUNK or SPAMMER, a default error text is used. dnl "check_relay3" uses the IP addresses: full address, or class a, b or c. dnl ACCEPT_SOME activates a backdoor: all entries must have the form dnl "user@address OK" or "domain OK". dnl dnl define(`_ACCEPT_SOME_',`hash -o /etc/mail/accept.db')dnl dnl HACK(`check_mail3', `btree -a@JUNK /etc/mail/junk.db')dnl dnl HACK(`check_relay3', `btree -a@JUNK /etc/mail/junk.db')dnl dnl --- some more snipped --- Since installing this I have not been successfully attacked (famous last words)! All the best Andrew
Eivind Olsen writes:
Hello. I'm currently running SuSe Linux 6.0, which I ham very happy with. But, I just noticed that it looks like the default setup of Sendmail allows for spam-relaying. What do I have to change to make sure it doesnt allow relaying?
I hope someone can help me here.. ;)
-- Eivind Olsen - eivindo@bgnett.no
--
----------------- Andrew Hougie, Rainbow House, London, England, NW6 1QE Email: andrew@hougie.co.uk WWW: <A HREF="http://www.hougie.co.uk"><A HREF="http://www.hougie.co.uk</A">http://www.hougie.co.uk</A</A>> -- To get out of this list, please send email to majordomo@suse.com with this text in its body: unsubscribe suse-linux-e Check out the SuSE-FAQ at <A HREF="http://www.suse.com/Support/Doku/FAQ/"><A HREF="http://www.suse.com/Support/Doku/FAQ/</A">http://www.suse.com/Support/Doku/FAQ/</A</A>> and the archive at <A HREF="http://www.suse.com/Mailinglists/suse-linux-e/index.html"><A HREF="http://www.suse.com/Mailinglists/suse-linux-e/index.html</A">http://www.suse.com/Mailinglists/suse-linux-e/index.html</A</A>>
participants (4)
-
andrew@hougie.co.uk
-
eivindo@bgnett.no
-
graham@barnowl.demon.co.uk
-
shawn@rbs.net