mail antispam

8/10/2019 Mail AntiSpam

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TRNG I HC S PHM K THUT TP.HCMKHOA: CNG NGH THNG TIN

BO CO CHUYN S1

ti:

DCH V MNG:MAIL-ANTISPAM

GVHD: NGUYN TH THANH VN

SVTH: HUNH VN BO - 09910001

TRN QUANG V - 09910097

TP. H Ch MinhNgy 20-11-2012


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MC LC

PHN 1: MC TIU V I TNG. ................................................................................................................................ 4

PHN 2: GII THIU. ............................................................................................................................................................... 4

2.1. Gii Thiu M Hnh Mng Tng Qut. ................................................................................................................ 42.1.1. V d m hnh mng tng qut ........................................................................................................................... 42.1.2. Cc bc chun b ci t. ................................................................................................................................... 5

2.2.

Cu hnh DNS. ............................................................................................................................................................ 6

2.2.1.

Trin khai DNS cho server2 ................................................................................................................................ 6

2.2.2. Ci t DNS vi gi bind trn server2 .............................................................................................................. 62.2.3.

Cu hnh Primary Name Server:......................................................................................................................... 7

2.2.4. Ci t trn client. ...............................................................................................................................................122.2.5. Kim tra s hot ng ca Server DNS: .........................................................................................................13

2.3. Gii thiu cu trc h thng e-mail. .....................................................................................................................14

2.4.

M hnh mail server vi postfix. ............................................................................................................................152.4.1. Cc gi i php cho mail server. ..........................................................................................................................15

2.4.2. Gii Thiu Cc Thnh Phn. .............................................................................................................................162.4.2.1. Gii Thiu Postfix. ...................................................................................................................................162.4.2.2. Gii Thiu Dovecot..................................................................................................................................172.4.2.3. Gii Thiu SquirrelMail. .........................................................................................................................172.4.2.4. Gii Thiu Thunderbird. .........................................................................................................................17

2.4.3. Yu cu h thng.................................................................................................................................................17

2.5. Vn bo mt cho h thng e-mail.....................................................................................................................172.5.1. AntiSpam:.............................................................................................................................................................18

2.5.1.1. Gii th iu DNS-Base Blocklists. ...........................................................................................................182.5.1.2. Gii th iu SpamAsssassin.......................................................................................................................18

2.5.2.

AntiVirus. .............................................................................................................................................................182.5.2.1. Gii th iu ClamA V. .................................................................................................................................18

PHN 3: TRIN KHAI & CI T N GIN.............................................................................................................19

3.1. Ci t Postfix v Dovecot. ....................................................................................................................................19

3.1.1. Ci t v cu h nh Postfix. ...............................................................................................................................193.1.2. Ci t v cu hnh Dovecot. ............................................................................................................................243.1.3. Ci t v cu h nh Thunderbird trn linux. ...................................................................................................253.1.4. Ci t v Cu Hnh OutLook Express trn XP. ..........................................................................................26

3.2.

Ci t Webmail vi SquirrelMail. ......................................................................................................................27

PHN 4 : TRIN KHAI & CI T C BO MT. ....................................................................................................29

4.1. CI T V CU HNH WEBMAIL SSL.................................................................................................29

4.2.

CU HNH DOVECOT V POSTFIX VI SSL. ................................................................................................34

4.3. CU HNH SMTP AUTHENTICATION S DNG DEVECOT SASL ..........................................................36

4.4. Ci t B Lc Spam. .............................................................................................................................................404.4.1.

Lc Spam Dng SpamAssassin. .......................................................................................................................40

4.5. Ci t AntiVirus. ....................................................................................................................................................42


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4.5.1.

Ci t ClamAV. ................................................................................................................................................42

4.5.2. Ci t Procmail (dng lc mail ti server)..............................................................................................48

PHN 4: KT LUN .................................................................................................................................................................51

Danh mc nh

Hnh 1.1Kin Trc Mail Server .........................................................................................................................14Hnh 1.2Kin trc Ma il Server vi Postfix ......................................................................................................15


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PHN 1: MC TIU V I TNG.

Mc tiu ca bo co l hng dn ngi c c th hiu kin trc vnguyn llm vic ca mt Mail Server, ng thi bit cch trin khai mt h thng Mail honchnh trn mi trng Linux Vi y cc thnh phn nh SMTP/POP3/IMAP

Server, AntiVirus, AntiSpam, v Mail Store. C th y l ci t Mail Server viPostfix trn nn h iu hnh CentOS5.8.

PHN 2: GII THIU.

Vi tc tin hc ha din ra kh nhanh nh hin nay, E -mail ngy cng tr thnhphng tin lin lc khng th thiu i vi mi ngi, nht l i vi cc doanh nghip.Chnh v nhu cu vic xy dng mt mail server l ht sc cn thit. Nhng vic chnxy dng mail server nh th no cho ph hp, hiu qu v tn t chi ph nht, ng thivn m bo c tnh sn sng (Availability Hot ng n nh, d dng nng cp v

bo tr ) v tnh ring t (Private Bo mt, b mt ) cho cc doanh nghip.

2.1.Gii Thiu M Hnh Mng Tng Qut.

2.1.1. V d m hnh mng tng qut

Trong :Ta c lp mng LAN: 10.0.0.0/8;

1. My server1 c eth0 IP=10.0.0.1 (IP mt trong) v eth1 IP=192.168.1.10(IP mt ngoi) ng vai tr Fiewall v Proxy c nhim v chia s kt nicc my trong LAN i ra Internet thng qua 1 ng line ADSL v trinkhai c ch Firewall gii hn kt ni t bn trong ra bn ngoi. Trn


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Fiewall cn ng vai tr Public cc server2 cc lient bn ngoi c thtruy cp WEB-Mail bn trong LAN.

2. My server2 c IP=10.0.0.2 ng vai tr DNS c nhim v phn gii tnmin bn trong mng LAN v mi trng Internet ng thi cp pht IPng cho cc client trong LAN thng qua dch v DHCP .

3.

My server3 c IP=10.0.0.3 trin khai dch v Apache lm Web server vtrin khai dch v Postfix lm Mail server.

Trong phm vi bi bo co ny ch dng 2 server2 v server3 khng dng nserver1 v cng khng trin khai dch v DHCP trn server2 m cu hnh IP tnhcho cc my trong lp mng 10.0.0.0/8.

2.1.2. Cc bc chun b ci t.1.1.1Cu hnh hostname

Ln lt t tn my cho cc my server2, server3:Trn server2:Dng lnh:

t tn my:

Restart li h thng: [root@thuchanh ~]# init 6Kim tra tn:root@thuchanh ~]# hostname

server2.thuchanh.com

1.1.2t IP cho cc LAN cardDng lnh: root@thuchanh ~]# vi /etc/sysconfi g/network -scri ps/i fcfg-eth0

Hoc: [root@thuchanh ~]# setup

Khi ng li dch v:[root@thuchanh ~]# service network restar t

1.1.3Kim tra IP: [root@thuchanh ~]# ifconfigTrn server3:Dng lnh:

t tn my:


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Restart li h thng: [root@thuchanh ~]# init 6Kim tra tn:root@thuchanh ~]# hostnameserver3.thuchanh.com

1.1.4t IP cho cc LAN cardDng lnh: root@thuchanh ~]# vi /etc/sysconfi g/network -scri ps/i fcfg-eth0

Hoc: [root@thuchanh ~]# setupKhi ng li dch v:[root@thuchanh ~]# service network r estar t

1.1.5Kim tra IP: [root@thuchanh ~]# ifconfig

Kim tra gia cc my: root@thuchanh ~]# ping 10.0.0.3

2.2.Cu hnh DNS.

2.2.1. Trin khai DNS cho server2Cc file cn thit cu hnh. File cu hnh chnh: named.conf File phn gii thun: thuchanh.db

File phn gii nghch: 0.0.10.in-addr.arpa.db File phan gii thun local: localhost.db File phn gii nghch: 0.0.127.in-addr.arpa.db File named.root

Ni dung chi tit bn di.

2.2.2. Ci t DNS vi gi bind trn server2- Kim tra ci cha:


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[ root@thuchanh ~]# rpmqa | grep bind- Ci t (nu cha c ci t):

Kim tra li sau khi ci:[ root@thuchanh CentOS]# rpm qa | grepbind

2.2.3.

Cu hnh Primary Name Server:To to file cu hnh named.conf trong th mc/var/named/chroot/etc/nhu sau:

[ root@thuchanh CentOS]# vi /var/named/chroot/etc/named.conf

acl mynet {10.0.0.0/8;127.0.0.1;

};options {

allow-transfer {none;};

directory "/var/named";query-source port 53;query-source-v6 port 53;dump-file "var/named/data/cache_dump.db";statistics-file "var/named/data/named_mem_stats.txt";notify yes;

};


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zone "." IN {type hint;file "named.root";

};

zone "localhost" IN {type master;file "localhost.db";

};zone "0.0.127.in-addr.arpa" IN {

type master;file "0.0.127.in-addr.arpa.db";

};zone "thuchanh.com" IN {

type master;

file "thuchanh.db";};

zone "0.0.10.in-addr.arpa" {type master;file "0.0.10.in-addr.arpa.db";

};

To file phn gii thun chnh: thuchanh.db trong th mc:

/var/named/chroot/var/named/ nhu sau:[ root@thuchanh CentOS]# vi /var/named/chroot/var/named/thuchanh.db $TTL 86400 ;@ IN SOA server2.thuchanh.com.root (

42 ; serial (d. adams)3H ; refresh15M ; retry1W ; expiry1D ) ; minimum

IN NS server2.thuchanh.com.

IN MX 10 server31D IN A 10.0.0.3server31D IN A 10.0.0.3server2 1D IN A 10.0.0.2server1 1D IN A 10.0.0.1www 1D IN CNAME server3mail 1D IN CNAME server3

ftp 1D IN CNAME server3


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To file phn gii thun local: localhost.db trong th mc:/var/named/chroot/var/named/ nhu sau:

[ root@thuchanh CentOS]# vi /var/named/chroot/var/named/localhost.db

$TTL 86400 ;@ IN SOA server2.thuchanh.com. root (

42 ; serial (d. adams)3H ; refresh15M ; retry1W ; expiry1D ) ; minimum

IN NS @IN A 127.0.0.1

To file phn gii nghch local : 0.0.127.in-addr.arpa.db trong thmc:/var/named/chroot/var/named/ nhu sau:

[ root@thuchanh CentOS]#vi /var/named/chroot/var/named/0.0.127.in-addr.arpa.db$TTL 86400 ;@ IN SOA localhost. root.localhost. (

42 ; serial3H ; refresh

15M ; retry1W ; expire1D ; minium);

IN NS localhost.1 IN PTR localhost.

To file phn gii nghch : 0.0.10.in-addr.arpa.db trong th mc:/var/named/chroot/var/named/ nhu sau:

[ root@thuchanh CentOS]# vi /var/named/chroot/var/named/0.0.10.in-addr.arpa.db

$TTL 86400@ IN SOA server2.thuchanh.com. root. (

3 ; serial


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3H ; refresh15M ; retry1W ; expire1D ; minimum);

@ IN NS server2.thuchanh.com.1 IN PTR server1.thuchanh.com.2 IN PTR server2.thuchanh.com.3 IN PTR server3.thuchanh.com.

To file named.roottrong th mc: /var/named/chroot/var/named/ nhu sau:

Nu c kt ni mng:

[ root@thuchanh CentOS]# cd /var/named/chroot/var/named[ root@thuchanh CentOS]# wget http: //www.internic.net/zones/named.root

Nu khng c mng:

[ root@thuchanh CentOS]# vi /var/named/chroot/var/named/named.root; This file holds the information on root name servers needed to

; initialize cache of Internet domain name servers; (e.g. reference this file in the "cache . "; configuration file of BIND domain name servers).;; This file is made available by InterNIC; under anonymous FTP as; file /domain/named.cache; on server FTP.INTERNIC.NET; -OR- RS.INTERNIC.NET;

; last update: Jun 8, 2011; related version of root zone: 2011060800;; formerly NS.INTERNIC.NET;. 3600000 IN NS A.ROOT-SERVERS.NET.A.ROOT-SERVERS.NET. 3600000 A 198.41.0.4A.ROOT-SERVERS.NET. 3600000 AAAA 2001:503:BA3E::2:30


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;; FORMERLY NS1.ISI.EDU;. 3600000 NS B.ROOT-SERVERS.NET.B.ROOT-SERVERS.NET. 3600000 A 192.228.79.201

;; FORMERLY C.PSI.NET;. 3600000 NS C.ROOT-SERVERS.NET.C.ROOT-SERVERS.NET. 3600000 A 192.33 .4.12;; FORMERLY TERP.UMD.EDU;. 3600000 NS D.ROOT-SERVERS.NET.D.ROOT-SERVERS.NET. 3600000 A 128.8.10.90

D.ROOT-SERVERS.NET. 3600000 AAAA 2001:500:2D::D;; FORMERLY NS.NASA.GOV;. 3600000 NS E.ROOT-SERVERS.NET.E.ROOT-SERVERS.NET. 3600000 A 192.203.230.10;; FORMERLY NS.ISC.ORG;. 3600000 NS F.ROOT-SERVERS.NET.

F.ROOT-SERVERS.NET. 3600000 A 192.5.5.241F.ROOT-SERVERS.NET. 3600000 AAAA 2001:500:2F::F;; FORMERLY NS.NIC.DDN.MIL;. 3600000 NS G.ROOT-SERVERS.NET.G.ROOT-SERVERS.NET. 3600000 A 192.112.36.4;; FORMERLY AOS.ARL.ARMY.MIL;. 3600000 NS H.ROOT-SERVERS.NET.H.ROOT-SERVERS.NET. 3600000 A 128.63.2.53H.ROOT-SERVERS.NET. 3600000 AAAA 2001:500:1::803F:235;; FORMERLY NIC.NORDU.NET;. 3600000 NS I.ROOT-SERVERS.NET.I.ROOT-SERVERS.NET. 3600000 A 192.36.148.17


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I.ROOT-SERVERS.NET. 3600000 AAAA 2001:7FE::53;; OPERATED BY VERISIGN, INC.;. 3600000 NS J.ROOT-SERVERS.NET.

J.ROOT-SERVERS.NET. 3600000 A 192.58.128.30J.ROOT-SERVERS.NET. 3600000 AAAA 2001:503:C27::2:30;; OPERATED BY RIPE NCC;. 3600000 NS K.ROOT-SERVERS.NET.K.ROOT-SERVERS.NET. 3600000 A 193.0.14.129K.ROOT-SERVERS.NET. 3600000 AAAA 2001:7FD::1;; OPERATED BY ICANN

;. 3600000 NS L.ROOT-SERVERS.NET.L.ROOT-SERVERS.NET. 3600000 A 199.7.83.42L.ROOT-SERVERS.NET. 3600000 AAAA 2001:500:3::42;; OPERATED BY WIDE;. 3600000 NS M.ROOT-SERVERS.NET.M.ROOT-SERVERS.NET. 3600000 A 202.12.27.33M.ROOT-SERVERS.NET. 3600000 AAAA 2001:DC3::35

; End of File

Khi ng named demon:[ root@thuchanh CentOS]# service named star t

2.2.4. Ci t trn cli ent. Client l Window XP:

T my windows: Khai bo Perferrer DNS server l IP caDNS server ta mi to trn.


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Client l Linux:

2.2.5. Kim tra s hot ng ca Server DNS:

Dng lnh nslookup kim tra: [ root@thuchanh CentOS]#nslookupwww.thuchanh.com
http://www.thuchanh.com/http://www.thuchanh.com/http://www.thuchanh.com/http://www.thuchanh.com/


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2.3.Gii thiu cu trc h thng e-mail.Cu trc v m hnh hot ng ca mt h thng mail thng c y cc thnh

phn nh sau:

Hnh 1.1Kin Trc Mail Server

Chc nng ca cc thnh phn nh sau:

o Mail User Agent (MUA): y l cc chng trnh gi v nhn mail c

ci t trn my ngi dng, n gip ngi dng qun l, son tho, nhnv gi mail mt cch tin li v nhanh chng. Cc chng trnh MUA tiu

biu l: Outlook (Windows), Evolution (Linux), ThunderBird va Eudora

o

Mail Transport Agent (MTA)(thng gi l Mail Transport Agent,Message Transfer Agent, or SMTP Daemond): L mt dch v trn mytnh c nhim v chuyn Email t my tnh n mt ni khc (MailDelivery Agent). Cc chng trnh cung cp dch v MTA tiu biu l:Qmail, Sendmail, Postfix (Linux), Edge/Hub Tranpost ca MS ExchangeServer (Windows).

o Mail Delivery Agent (MDA): L Dch v tip nhn cc Email v phn

phi chng n cc hp th c nhn. Cc chng trnh cung cp dch vtiu biu l: Procmail, Mail.local, rmail (Linux), Mailbox Server trong MSExchange (Windows).

o Mail Submission Agent (MSA):L chng trnh nhn Email t MUA quacng 587 (Bo mt hn SMTP cng 25 v n i hi Authenticate hay cchnh ng tng t chng spam trong local) v kt hp vi MTA chuyn Email. a s cc MTA lm nhim v MSA lun (posfix,


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Sendmail), trn MS Exchange th MSA do Mailbox role + Client receiveconnector (trn Hub transport role) m nhim.

o Mail Access Agent/ Mail Retrieval Agent (MAA/MRA): MRA l

chng trnh tm v hoc ly Email v t remote Mail server, v kt hpvi MDA phn phi mail v local hoc remote mailbox. MAA l dch vcung cp truy cp n tm kim v ly email v. Cc chng trnh tiu

biu: IMAP, POP3 Server, dovecot (Linux), Client Access Server trn MSExchange (Windows). MRA by gi thng do cc MUA m nhim chnh l cc POP3, IMAP Client.

2.4.M hnh mail server vi postfix.

Bo co hng dn cho ngi cc th d dng xy dng mt mail serverhot ng n nh v chi ph thp, cho doanh nghip va v nh, da trn nn Linux.

Hnh 1.2Kin trc Mail Servervi Postfix

2.4.1.

Cc gii php cho mail server.

C rt nhiu hng trn th gii cung cp cc gii php trn gi cho h thngmail cho cc doanh nghip va v nh nh IBM, Microsoft, TrenMicro, Cisco Vi y cc thnh phn chuyn dng nh: Mai l Server, AntiSpam, AntiVirus

Ngoi ra cn c cc hng cung cp cc phn mm v gii php Mail Server chocc doanh nghip khc, nhng ch yu chy trn nn Linux hoc Windows.


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- Cc gii php vi thit b chuyn dng: c cung cp bi cc hng nhIBM, Cissco u im: Thit b ng b, hot ng n nh, tnh chu li cao, d

dng nng cp v m rng, bo mt cao, d dng qun tr h thng,

c h tr k thut trc tip t nh cung cp. Nhc im:Gi thnh cao

- Cc gii php trn nn Windows:c Microsoft cung cp vi h thngPhn cng chuyn dng hoc phn mm. u im:D dng qun tr v trin khai, hot ng n nh, bo mt

cao, d dng nng cp v m rng, h tr k thut trc tip t nh snxut.

Nhc im:Gi thnh tng i, yu cu v ti nguyn phn cng cao(i vi phn mm).

- Cc gii php trn nn Linux Unix: c mt vi cng ty phn phihoc t chc pht trin. u im: Hot ng n nh, c kh nng chu li tt, yu cu ti

nguyn phn cng thp, bo mt cao, min ph, c tr gip tcng ng s dng.

Nhc im:Kh qun tr v trin khai, nng cp v m rng tng iphc tp.

C rt nhiu phn mm Mail Server c ngun ng v ngun m nh:Mdaemon Server, Exchange Server, IBM Lotus Domino, Postfix, Exim, Qmail,

SendMail,Do , cc h thng Linux rt ph hp vi cc doanh nghip va v nh

(thm ch l cc doanh nghip c ln nu admin c kh nng xy dng v quntr). Chn trin khai Postfix v y l mt trong nhng h thng mail ph binchy trn nn Linux, v CentOS cng l mt trong nhng Distro Linux kh ph

bin v hot ng tng i n nh. V cng c kh nhiu doanh nghip trinkhai theo m hnh ny.

2.4.2. Gii Thiu Cc Thnh Phn.

2.4.2.1.

Gii Thiu Postfix.

Postfix l mt MTA c vit bi Wietse Venema khi ng ang lmvic trung tm nghin cu T. J. Watson ca IBM. c im ca Postfix: dqun l, nhanh, an ton. Ch cn mt server vi hardware thng thng,Postfix c th chuyn giao hng triu email mt ngy. Ngy nay postfix l mttrong nhng MTA kh ph bin trn cc mail server.


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2.4.2.2. Gii Thiu Dovecot.

Dovecot l mt MAA cung cp cc dch v IMAP v POP3 c ci

ph bin trn cc CentOS, N l mt phn mm m ngun m c TimoSirainen vit v pht trin. c im ca Dovecot l: bo mt, nhanh v dqun l.

2.4.2.3. Gii Thiu SquirrelMail.

SquirrelMail l mt trong nhng Web mail ph bin nht trn cc MailServer, n h tr c cc giao thc IMAP/POP3 v SMTP, c vit bngPHP4 v l mt phn mm m ngun m, n gip ngi dng c th c vqun l e-mail ca mnh trong mi trng Web.

2.4.2.4. Gii Thiu Thunderbird.Thunderbird l mt phn mm dng MUA v l d n pht trin ca

Mozzila nn tt nhin n l m ngun m, quan trng ging nh FirefoxThunderbird h tr a h iu hnh Linux, Windows, Mac OS X,... nn skhng phi bn khon khi chuyn t h iu hnh ny sang h iu hnhkhc. Vic ng b a ch email cng s tr nn n gin hn.

2.4.3. Yu cu h thng.

Vi cc h thng Linux yu cu v phn cng rt bnh thng, mt servervi cu hnh trung bnh vn c th ci t v chy n nh.

V phn cc phn mm trn h thng:- H iu Hnh: CentOS 5.8 Chy dng command Line hay ha

u c.- SMTP Server: Postfix- POP3/IMAP Server- Web Mail: SquirrelMail- Web Server: Apache . Cn thit cho User c th dng web mail.- AntiSpam: SpamAssassin-

AntiVirus: ClamAV , Amavisd-new

2.5.Vn bo mt cho h thng e-mail.

Ngy nay vn Virus v spam vn l nhng nguy c e da n s vn hnhn nh ca h thng, ng thi nguy c mt mt hoc b nh cp d liu l rt cao,


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iu ny nh hng trc tip n li ch ca ngi dng v doanh nghip. V th khitrin khai xy dng h thng mail cho doanh nghip cn phi tnh ti cc vn v

bo mt chng Spam v Virus.

2.5.1.

AntiSpam:

2.5.1.1. Gii thiu DNS-Base Blockl ists.

UCE (unsolicited commercial email), hay spam, thng c gi tnhng mail server c vi c im nht nh. V d, t nhng server c cuhnh khng hon chnh (open relay, khng tun th tiu chun RFC), nhngserver khng c thng tin r rng v ngi qun tr (my kt ni bng dial -up,my khng c reverse DNS), hay t nhng server chuyn gi spam. Ngi ta lp c danh sch nhng mail server nh vy, danh sch ny c updatethng xuyn, gi chung l RBL (real-time blackhole list), hay DNSBL (DNS-

based Blocklist). u im ca phngphp ny l kim tra nhanh t hao tn tinguyn ca server v bc kim tra c thc hin trc khi gi mail v vickim tra ch da vo kt qu tm kim ca DNS.

2.5.1.2. Gii thiu SpamAsssassin.

SpamAssassinpht hin v nh du spam mail bng cch phn tchthng tin trong header v ni dung mail. SpamAssassin tiu tn kh nhiu tinguyn (cpu, memory, thi gian x l) ca server, c bit khi phi x l

nhng mail c size ln. u im ca vic dng SpamAssassin l t thay icu hnh mc nh ca postfix v c th xy dng quy tc kim tra spam choring mnh.

SpamAssassin l mt project c pht trin bi Apache, SpamAssassinc ng dng kh nhiu trn cc mail server dng nn Linux.

2.5.2. AntiVirus.

Dng chng vic ly lan Virus trong thng qua h thng mail, ng thi

hn ch s ly lan ca Virus khi mt my no trong mng b nhim. C haichng trnh antivirus ph bin dng trn mail server l ClamAV v Amavisd-new.

2.5.2.1. Gii thiu ClamAV.
http://spamassassin.apache.org/http://spamassassin.apache.org/http://spamassassin.apache.org/


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Chuyn qua MTA: dng postfix:

Cu hnh:

G ESC :set nu hin th s dng:

Di chuyn ti dng 71:Khai bo hostname bng cch b du # v sa li hostname v thm dng 73khai bo thm thmuc chadatabase ca postfix:

Di chuyn tip ti dng 81: khai bo mydomain

Di chuyn tip ti dng 98: khai bo myorigin


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]Di chuyn tip ti dng 112: khai bo interface

Di chuyn tip ti dng 162: khai bo cc ch n c th gi mail

Di chuyn tip ti dng 261: khai bo lp mng

Di chuyn tip ti dng 418: khai bo th mc lu th l Maildir thay vmc nh l MailDir.Dng lu tr Maildir tt hn so vi dng lu tr Mailbox,tuy nhin ty vo nhu cu c th m chn kiu lu tr cho thch hp.


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Khi ng li postfix:

To hp mail cho user:

By gi c th dng postfix c ri Kim tra postfix hot ng tt cha bngcch kt ni th n cng 25:

Th s dng b lnh: Esmtp


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3.1.2. Ci t v cu hnh Dovecot.

Kim tra xem ci cha:

Ci t t gi rpm(nu cha ci t):

Cu hnh dovecot:

Di chuyn ti dng 21: chn protocols = pop3 pop3s imap imaps

Tin hnh khi ng li dovecot:

Kim tra li dovecot hot ng tt cha bng cch kt ni n cng 110


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3.1.3. Ci t v cu hnh Thunderbird trn linux.

Kim tra lithunderbird c ci cha:

Ci t (nu cha ci t):

Khi ng chng trnh Thuderbird:

Cu hnh chng trnh Thuderbird duyt mail POP3:

Tip tc t gi mail v xem ni dung mail:


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3.1.4.

Ci t v Cu Hnh OutLook Express trn XP.

Tip tc t gi mail v xem ni dung mail:


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3.2.Ci t Webmail vi SquirrelMail .Lu : Trc tin cn phi ci t web server, imap server v phmaip.


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Trn client XP:

Trn cl ient l inux:

PHN 4 : TRIN KHAI & CI T C BO MT.

4.1.

CI T V CU HNH WEBMAIL SSL.Ci t:

Cu hnh squirrelmail:


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[root@server3 ]# vi /etc/squirrelmail/config.php

Sa dng cc dng sau:

30 $domain = 'thuchanh.com';31 $imapServerAddress = 'mail.thuchanh.com';

34 $smtpServerAddress = 'mail.thuchanh.com';

To certificate(Giy chng nhn) cho websitewww.thuchanh.com

Bc 1: ci t

[root@server3 ]# yum install mod_ssl

Bc 2: To 1024-bit RSA private key cho Apache server

Kt qu: file server.key c to ra .

Remove key trong file server.key


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Bc 5: cu hnh httpd.conf

[ root@server3 certs]#vi /etc/httpd/conf.d/ssl .conf

Chnh sa cc dng sau:

84 DocumentRoot " /var /www/html"

85ServerName www.thuchanh.com:443

112 SSLCerti f icateFi le /etc/pk i/ tls/certs/server .cr t

119SSLCer ti f icateKeyFi le /etc/pk i /tl s/cer ts/server .key

To ni dung web:www.thuchanh.com[root@server3 cer ts]# echo " Chuye de S1: Mail -Anti spam xi n chao co va2

cac ban


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" > /var/www/html /myweb/index.html

Khi ng li dch v:

Kim tra bng cch thtruy cp ta ch:

https://www.thuchanh.com/myweb

Ci t plugin c thssng chc nng i password:

[root@server3 home]# /usr/share/squirrelmail/config/conf.pl

Chn 8: [root@server3 home]# /usr/share/squirrelmail/config/conf.pl

SquirrelMail Configuration : Read: config.php (1.4.0)

---------------------------------------------------------

Main Menu --

1. Organization Preferences

2. Server Settings

3. Folder Defaults

4. General Options

5. Themes


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6. Address Books

7. Message of the Day (MOTD)

8. Plugins

9. Database

10. Languages

D. Set pre-defined settings for specific IMAP servers

C Turn col or off

S Save data

Q Quit

Command >> 8

Ln lt chn tip:

change_pass v compatibility

Cui cng lu li:

Q

Khi ng li dch v:

[root@server3 certs]# service httpd restart

4.2.CU HNH DOVECOT V POSTFIX VI SSL.

SSL :Secure Sockets Layer (socket 443).

TLS: Transport Layer Security


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K thut htrm ha thng tin ng truyn gi a 2 hostname.

Bc 1: Cu hnh postfix

[root@server3 ~]# vi /etc/postfix/main.cf

Thm vo cui file

671 #them vao

672smtpd_use_tl s = yes673 smtpd_tls_cert_file = /etc/pki/tls/certs/server.crt

674 smtpd_tls_key_file = /etc/pki/t ls/certs/server.key

675 smtpd_tls_session_cache_database = btree:/etc/postfix/smtpd_scache

[root@server3 ~]# vi /etc/postfix/master.cf

Chnh sa cc dng 14,15,16

14 smtps inet n - n - - smtpd15 -o smtpd_tls_wrappermode=yes

16 -o smtpd_sasl_auth_enable=yes

Cu hnh dovecot

[ root@server3 ~]# vi /etc/dovecot.conf

Chnh sa cc dng 85,91,92 nh sau:

85 ssl_di sable = no

91ssl_cert_f i le = /etc/pki /tl s/certs/server .cr t

92 ssl_key_f i le = /etc/pk i /tl s/cer ts/server .key


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Khi ng li dch v

[root@server3 ~]# service postfix restart

Shutting down postfix: [ OK ]

Starting postfix: [ OK ]

[root@server3 ~]# service dovecot restart

Stopping Dovecot Imap: [ OK ]

Starting Dovecot Imap: [ OK ][root@server3 ~]#

4.3.CU HNH SMTP AUTHENTICATION S DNG DEVECOT SASL

SASL (Simple Authentication and Security Layer)

K thut htrchng thc user sdng username va password

Bc 1: Cu hnh SASL cho postfix

[root@server3 plugins]# vi /etc/postfix/main.cf

Thm cc dng sau vo cui file

676 smtpd_sasl_type = dovecot

677 smtpd_sasl_path = private/auth

678 smtpd_sasl_auth_enable = yes

679 broken_sasl_auth_clients = yes

680 smtpd_recipient_restrictions =

681 permit_mynetworks

682 permit_sasl_authenticated

683 reject_unauth_destination

[root@server3 nv1]# vi /etc/postfix/master.cf

Chnh sa li cc dng nh sau:

10 submission inet n - n - - smtpd


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11 -o smtpd_enforce_tls=yes

12 -o smtpd_sasl_auth_enable=yes

13 -o smtpd_client_restrictions=permit_sasl_authenticated,reject

Cu hnh dovecot

[root@server3 ]# vi /etc/dovecot.conf

Chnh cc dng sau nh sau:

758 auth default {

762 mechanisms = plain logi n

796 passdb pam {}

897 userdb passwd {

}

960 user = root

979 socket li sten {

990 cli ent {

994 path = /var/spool /postfix/private/auth

995 mode = 0660

996 user = postfix997 group = postfix

}

}

}

Bc 2: Khi ng li dch cc dch v

[root@server3 nv1]# service dovecot restart

[root@server3 nv1]# service postfix restart

Bc 3: kim tra li

[root@server3 ~]# ls -lh /var/spool/postfix/private/auth


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srw-rw---- 1 postf ix postf ix 0 Nov 26 17:04 /var /spool/postf ix /pr ivate/auth

[root@server3 ~]#

Bc 4: Tin hnh encode user: nv1, pass 123456

[root@server3 plugins]#perl -MMIME::Base64 -e 'print

encode_base64("\000nv1\000123456");'

AG52MgAxMjM0NTY=

Chp AG52MgAxMjM0NTY= dng chng thc

Bc 5: Kim tra

[root@server3 awstats]# telnet mail.thuchanh.com 25

Trying 10.0.0.3...Connected to mail.thuchanh.com (10.0.0.3).

Escape character is '^]'.

220 mail.thuchanh.com ESMTP Postfix

EHLO thuchanh.com

250-mail.thuchanh.com

250-PIPELINING

250-SIZE 10240000

250-VRFY

250-ETRN

250-STARTTLS250-AUTH PLAIN LOGIN

250-AUTH=PLAIN LOGIN

250-ENHANCEDSTATUSCODES

250-8BITMIME

250 DSN

AUTH PLAIN AG52MgAxMjM0NTY=

235 2.0.0 Authentication successful

mail from:[email protected]

250 2.1.0 Ok

rcpt to:[email protected]

250 2.1.5 Ok

data

354 End data with .

chao nv1

.250 2.0.0 Ok: queued as 183AC27F2E

quit


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221 2.0.0 Bye

Connection closed by foreign host.

Kim tra chi tit trong fil e mail log[root@server3 awstats]# tail /var/log/maillog

Nov 26 17:33:32 server3 postfix/smtpd[16811]: 183AC27F2E:

client=server3.thuchanh.com[10.0.0.3], sasl_method=PLAIN,

sasl_username=nv2

Bc 6:Khi ng li Postfix v kim tra cc cng

[root@server3 nv1]# openssl s_client -connect thuchanh.com:587 -starttls smtp

---

SSL handshake has read 1758 bytes and wri tten 354 bytes

---

New, TLSv1/SSLv3, Cipher i s DHE-RSA-AES256-SHA

Server publi c key is 2048 bit

Secure Renegotiation IS supported

Compression: NONE

Expansion: NONESSL-Session:

Protocol : TLSv1

Cipher : DHE-RSA-AES256-SHA

Session-ID:

7FA0C5124BA796B9F03B3FECF20AFDC95D826DDCCF4FD5DDF61D5FCAF379

E4C5

Session-ID-ctx:

Master-Key:

973BF6A5238BDF1181E19870151CB9CA09DAABEFACF34A4A0E54CD75850E33

7A5566D5701406E9A32E63783105AF38ECKey-Arg : None

Krb5 Principal: None

Start Time: 1353930966

Timeout : 300 (sec)

Verify return code: 18 (sel f signed certi ficate)---

250 DSN


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AUTH PLAIN AG52MgAxMjM0NTY=

235 2.0.0 Authentication successful

quit221 2.0.0 Bye

read:errno=0

4.4.Ci t B Lc Spam.

4.4.1. Lc Spam Dng SpamAssassin.

Kim tra spamassassin c ci t cha:

Ci t spamassassin bng lnh:

Cu hnh spamassassin:Dng lnh vi sa file cu hnh /etc/postfix/master.cf

Sa dng 11: o content_filter=spamassassin (ci thng s ny ni vipostfix mail m mail gi n postfix s c chuyn n cho

spamassassin thc hin vic qut ni dung, cng nh l header mail)

Thm vo dng 80: (dng ny s thc hin vic to mt service mi ckiu unix trong file master.cf ny n s thc hin gi mt deamon dngpiple ca postfix phn pht mail thng qua lnh spamc tin hnhqut mail pht hin spam sau dng lnh sendmail gi ngc mail

v cho postfix

Lu li file cu hnh.Kim tra port 783:


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Khi spamassassin pht hin mail spam th n chn vo phn subject caemail mt chui nhn din spam: [SPAM]Ta dng lnh vi xem:

4.5.Ci t AntiVirus.

4.5.1. Ci t ClamAV.Dng lnh rpm ci t cc gi clamav-db, clamav, clamd


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Dng lnh tar gii nn file clamsmtp

Duy chuyn vo th mc clamsmtp-1.10


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Ci gi clamsmtp

Dng lnh make bt u chng trnh

Sau khi bin dch xong ta g lnh make install tin hnh ci t


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Tch hp antivirus vi h thng mail postfix:

Dng lnh vi /etc/posfix/main.cf chnh sa file cu hnh main.cfTa thm hai dng sau vo file main.cfDng 669 c ngha l thc hin vic chuyn mail postfix n port10025 thc hin vic qut virusDng 700 dng ny c ngha l ngn cn postfix m rng n cc aliasmail hoc group trnh trng hp buket cache mail nhn c.

Dng lnh vi /etc/postfix/master.cf chnh sa file cu hnh master.cfDng ny c nghi to mt dch v scan qut cc thng tin t smtpgi n

Dng ny c ngha gi tr mail li postfix, nhng option cn li ngn

cn vic loop sy ra


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Copy file clamsmtpd.conf vo th mc etccp /Sofware/clamsmtp-1.10/doc/clamsmtpd.conf /etc/Dng lnh vi cu hnh fileclamsmtpd.confvi /etc/clamsmtpd.conf

Khi c mt mail c virus th Action: bounce gi tr li cho ngi gi,

pass chp nhn mail, drop hy mail i.

Sau khi cu hnh xong lu liChy lnh clamsmtpd cp nht li

Tin hnh gi mail kim tra


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4.5.2. Ci t Procmail (dng lc mail ti server) .

Ngi qun tr c th thng qua procmail kt hp vi tin chSpamassassin. Khi mt mail n c pht hin l spam th n s xahn mail i hoc l move n vo mt folder c bit, gii php xahn mail s mang tnh ri ro cao v mt mail b pht hin spam c thkhng phi l mt mail spam, v th ngi ta thng chn gii php lmove n vo mt folder c bit ri c n sau. Ta tin hnh to mt h thng th mc cho h thng mail pht hinspam

Dng lnh tree a kim tra:

i vi nhng user mi to ra ta tao thu mc ny trong mt templex


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Dng lnh ls kim tra:

Dng lnh tree xem:

Ta tin hnh to User nv4 kim tra:


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Ta thy nv4 khi to ra c mt th mc spam cha cc mail spamDng lnh vi /etc/postfix/main.cf chnh sa file cu hnh ca postfix

Sa dng 439:

Mailbox_command ni vi postfix s dng procmail duy chuyn th

cng vi cc thng s xc nh th mc maildir cha th ca hp thc nhnDng lnh vi tofile procmailrc trong thu mc etc file ny t to chkhng c sn

y l on script ca procmailrc s tin hnh qut header ca email nhn bit c mail spam sau move n vo th mc spamXa lun mail spam


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Khi ng lipostfixKhi ng spamassassin

Gi 2 mail, mt mail spam, mt mail khng spam kim traMail spam s nm trong th mc spam, cn mail khng spam nm trongth mc ngoi th mc spam

PHN 4: KT LUN

Bi bo co c bn hon thnh vic ci t cc dch v mail server trn h thngLINUX nhng vn cn nhiu thiu st nh cha gi mail ngoi domain, cha khai thctrit cc option trong file cu hnh ca cc dch v Do thi gian khng nhiu nn vic

mail antispam

Documents