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ti mn: Qun tr mng LP: CT0801 ti: SSL,SSH LINUX(OPEN SSL) Gio vin hng dn: Lng Uy TnM s nhm: 07 M s ti: 21 Thng tin nhm: STT 1 2 MSSV 08CD65054 08CD65112 H V TN Nguyn Hong Thi V Nht Trng IN THOI 0985265756 0914703307 EMAIL Sumo008@yahoo.com.vn Theanh0708@yahoo.com

Gii thiu v ti1.-

Gii thiu v giao thc SSH:

Cc nh qun tr h thng lun c gn gi cho h thng ca h c bo mt, an ton bng cc cch th nh: nng cp, ci t

cc bn sa li bo mt. Nhng c mt thc t cn phi nhn thc v thay i lm m bo an ton ngay trong vic trao i d liu gia cc h thng t bit l m bo an ton khi m cc phin lm vic xa qua mng. mt trong nhng cch hu hiu nht trong vn ny l s dng c ch ng nhp bo mt(Secure Shell - SSH). SSH l mt chng trnh tng tc gia my ch v my khch c s dng c ch m ho mnh nhm ngn chn cc hin tng nghe trm, nh cp thng tin trn ng truyn. Cc chng trnh trc y: telnet, rlogin khng s dng phng php m ho. V th bt c ai cng c th nghe trm thm ch c c ton b ni dung ca phin lm vic bng cch s dng mt s cng c n gin. S dng SSH l bin php hu hiu bo mt d liu trn ng truyn t h thng ny n h thng khc.-

Cch thc lm vic ca SSH thng qua 3 bc n gin: nh danh host: Vic nh danh host c thc hin qua vic trao i kho. Mi my tnh c h tr kiu truyn thng SSH c mt kho nh danh duy nht. Kho ny gm hai thnh phn: kho ring v kho cng cng. Kho cng cng c s dng khi cn trao i gia cc my ch vi nhau trong phin lm vic SSH, d liu s c m ho bng kho cng khai v ch c th gii m bng kho ring. Khi c s thay i v cu hnh trn my ch: thay i chng trnh SSH, thay i c bn trong h iu hnh, kho nh danh cng s thay i. Khi mi ngi s dng SSH ng nhp vo my ch ny u c cnh bo v s thay i ny. Khi hai h thng bt u mt phin lm vic SSH, my ch s gi kho cng cng ca n cho my khch. My khch sinh ra mt kho phin ngu nhin v m ho kho ny bng kho cng cng ca my ch, sau gi li cho my ch. My ch s gii m kho phin ny bng kho ring ca mnh v nhn c kho phin. Kho phin ny s l kho s dng trao i d liu gia hai my. Qu trnh ny c xem nh cc bc nhn din my ch v my khch.

M ho: Sau khi hon tt vic thit lp phin lm vic bo mt (trao i kho, nh danh), qu trnh trao i d liu din ra thng qua mt bc trung gian l m ho/gii m. iu

c ngha l d liu gi/nhn trn ng truyn u c m ho v gii m theo c ch tho thun trc gia my ch v my khch. Vic la chn c ch m ho thng do my khch quyt nh. Cc c ch m ho thng c chn bao gm: 3DES, IDEA, v Blowfish. Khi c ch m ho c la chn, my ch v my khch trao i kho m ho cho nhau. Vic trao i ny cng c bo mt da trn inh danh b mt ca cc my. K tn cng kh c th nghe trm thng tin trao i trn ng truyn v khng bit c kho m ho. Cc thut ton m ho khc nhau v cc u, nhc im ca tng loi: o 3DES (cng c bit nh triple-DES) -- phng php m ho mc nh cho SSH. o IDEA -- Nhanh hn 3DES, nhng chm hn Arcfour v Blowfish. o Arcfour -- Nhanh, nhng cc vn bo mt c pht hin. o Blowfish -- Nhanh v bo mt, nhng cc phng php m ho ang c ci tin. Chng thc: Vic chng thc l bc cui cng trong ba bc, v l bc a dng nht. Ti thi im ny, knh trao i bn thn n c bo mt. Mi nh danh v truy nhp ca ngi s dng c th c cung cp theo rt nhiu cch khc nhau. Chng hn, kiu chng thc rhosts c th c s dng, nhng khng phi l mc nh; n n gin ch kim tra nh danh ca my khch c lit k trong file rhost (theo DNS v a ch IP). Vic chng thc mt khu l mt cch rt thng dng nh danh ngi s dng, nhng ngoi ra cng c cc cch khc: chng thc RSA, s dng ssh-keygen v ssh-agent chng thc cc cp kho.

- Ni ngn gn, SSH l mt phng php (hoc k thut mt cht th n l mt giao thc (protocol)) dng kt ni hai my tnh di hnh thc m ha an ton. Khi hai my tnh c kt ni vi nhau thng qua SSH, tt c d liu truyn ti gia chng u c m ha. ng hm SSH (SSH Tunneling) n gin ch l mt phng php m chng ta s dng my tnh c kt ni mng nh mt proxy duyt web. Khi chng ta duyt web (vi trnh duyt ca mnh) thng qua ng hm SSH, proxy server s truy lc ni

dung web v gi n quay tr li my tnh ca mnh thng qua kt ni an ton. Hai u im chnh trong vic s dng SSH l: Che giu c a ch IP ca bn. To kt ni an ton trnh cc hacker c th nh hi thy d liu ca bn.

- SSH ch yu c s dng trong Linux v Mac, tuy nhin ngi dng Windows cng c th s dng SSH vi Cygwin.

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Lch s pht trin: SSH1 v giao thc SSH-1 c trnh by nm 1995 bi Tatu Ylnen, mt nh nghin cu trng i hc k thut Helsinki ca Phn Lan. Sau khi mng trng i hc ca ng ta l nn nhn ca mt cuc tn cng nh cp password vo u nm . Thng 7 nm 1995, SSH1 c pht hnh rng ri di dng mt phn mm min ph c source code, cho php mi ngi sao chp v s dng m khng thu ph. Vo cui nm , c tnh c khong 20.000 ngi dng trn 50 quc gia s dng SSH1, v mi ngy Ylnen nhn 150 mail yu cu h tr. p li, Ylnen thnh lp SSH Communications Security (SCS, Tectia.com / en) vo thng 12 nm 1995 duy tr, thng nghip ho v tip tc pht trin SSH. Cng trong nm 1995, Ylnen son tho giao thc SSH-1 cn gi l Internet Engineering Task Force (IETF), n din t hot ng c bn ca phn mm SSH1 trn thc t. N l mt giao thc c phn qung co nhng cn mt s li v gii hn nhng rt ph bin. Nm 1996, SCS gii thiu mt phin bn mi l phin bn chnh ca giao thc, SSH 2.0 hay SSH-2, phin bn ny c kt hp cht ch nhng thut ton mi v khng hp vi SSH-1. Trong lc , IETF thnh lp mt nhm lm vic gi l SECSH (Secure Shell) chun ho giao thc v ch o s pht trin ca n trn li ch chung. Nhm lm vic SECSH trnh by bn phc tho Internet u tin i vi giao thc SSH-2 vo thng 2 nm 1997.

Nm 1998, SCS pht hnh sn phm phn mm SSH Secure Shell (SSH2), da trn giao thc SSH-2. Tuy nhin, SSH2 khng thay th SSH1 trong mt s lnh vc, c 2 l do. Th nht, SSH2 khng c mt s tin ch, cc c im c ch v cu hnh tu chn nh SSH1. Th hai, SSH2 c nhiu gii hn v vic ng k. Bn chnh SSH1 c sn min ph t Ylnen v trng i hc k thut Helsinki. Phin bn mi hn ca SSH1 t SCS vn c sn min ph cho hu ht ngi dng, thm ch c cu hnh thng mi cng min ph ch cn phn mm khng c trc tip bn cho vic thu li nhun hoc c tng nh l mt dch v cho khch hng. V th, tuy SSH2 xut hin, nhng hu ht nhng ngi ang s dng SSH1 u nhn ra vi u im ca SSH1 so vi SSH2 v tip tc s dng SSH1, ba nm sau khi SSH2 ra i th SSH1 vn l phin bn c s dng ph bin trn Internet v vt qua c SSH2 l giao thc tt hn v bo mt hn. Tuy nhin, SSH2 cng c hai s pht trin ha hn, l mt bn ni lng ca SSH2 bn quyn v s xut hin SSH-2 b sung. Nm 2000, SCS m rng SSH2 bn quyn cho php s dng khi lm vic ring l i vi cc t chc hot ng phi li nhun. N cng c m rng cho php dng min ph i vi Linux, NetBSD, FreeBSD v hiu hnh OpenBSD. Cng thi gian , OpenSSH (OpenSSH) c pht trin ni bt nh l mt SSH b sung, c pht trin di hot ng ca d n OpenBSD (OpenBSD) v min ph sn bn di OpenBSD c ng k. OpenSH h tr c SSH-1 v SSH-2 trong mt chng trnh. Tuy OpenSSH c pht trin trn nn OpenBSD nhng n cng hot ng c trn Linux, Solais, AIX v nhng hiu hnh khc. Mc d OpenSSH tng i mi v khng c vi c im c trong SSH1 v SSH2 nhng n ang trn pht trin nhanh chng v ha hn tr thnh bn SSH chnh trong tng lai khng xa.

2.

Tng quan ti:

- H iu hnh Ubuntu l mt trong nhng bn Linux kh thng dng. Trn Windows c kh nhiu cng c h tr vic iu khin, qun tr Ubuntu thng qua mng. Vic s dng cc cng c trn h

iu hnh Windows s gip ngi qun tr thao tc d dng hn, hiu qu hn m khng cn phi ngi trc tip ti Ubuntu. - Trong bi vit ny s hng dn cc cng c kt ni n Ubuntu c th thc hin cc lnh ssh. Do mi cng c cng c kh nhiu tnh nng v c nhiu khi nim lin quan n Linux n trong bi vit ny s hng dn cch thc hin n gin nht. Cc cng c c gii thiu: Phn mm thng mi Xmanager Enterprise (phin bn 3) vi cc cng c Xshell, Xftp, Xmanager. y l mt b cng c y v hon chnh trong vic kt ni n h iu hnh Linux, Solaris iu khin v qun tr. Phn mm min ph: Putty, WinSCP, Nomachine NX Free. Mi cng c min ph ny c nhng tnh nng ring, nu tnh c 3 cng c th cc chc nng chnh cng c th so snh c vi Xmanager Enterprise. - H iu hnh Ubuntu l mt trong nhng bn Linux kh thng dng. Trn Windows c kh nhiu cng c h tr vic iu khin, qun tr Ubuntu thng qua mng. Vic s dng cc cng c trn h iu hnh Windows s gip ngi qun tr thao tc d dng hn, hiu qu hn m khng cn phi ngi trc tip ti Ubuntu. Trong bi vit ny s hng dn cc cng c kt ni n Ubuntu c th thc hin cc lnh (telnet/ssh), truyn file n Ubuntu (sftp), kt ni n giao din ha ca Ubuntu. Do mi cng c cng c kh nhiu tnh nng v c nhiu khi nim lin quan n Linux n trong bi vit ny s hng dn cch thc hin n gin nht. Cc cng c c gii thiu: Xmanager Enterprise: cc bn c th dow bn min ph ca phn mm ny ti: http://www.mediafire.com/?iyzvmmzzznf

Putty: http://www.mediafire.com/?jlaj5yzh3ilqknk

Cc bc thc hinKt ni n ca s lnh vi giao thc SSH

OpenSSH l gi phn mm bao gm cc cng c nh: ssh, sshd, scp, ... Trn Ubuntu s c ci t gi phn mm ny. Khi trn Windows ch cn cng c h tr ssh nh Putty, Xshell l c th kt ni n Ubuntu thc hin cc lnh trn .-

Ci t Openssh trn Ubuntu

Gi phn mm openssh thng c la chn ngm nh khi ci h iu hnh Ubuntu Server. i vi bn Ubuntu Desktop, gi phn mm ny khng c chn ci ngm nh. Trn Ubuntu Desktop c th ci t openssh theo mt trong hai cch sau: Ci qua dng lnh: trn ca s Terminal ca Ubuntu, g lnh sau:-

sudo apt-get install openssh-server sudo apt-get install openssh-client Sao khi g cu lnh trn m hin dng E: Invalid operation intall th bn thnh cng vic ci openssh. S dng cng c Synaptic Package Manager: click menu System -> Administration -> Synaptic Package Manager. Trn giao din ca cng c Synaptic Package Manager, search vi t kha l openssh, sau chn 2 gi openssh-client v openssh-server, sau bm apply tin hnh ci, nh l lc ny my phi c kt ni vi internet.-

Kt ni Windows ti Ubuntu

ci t ip cho my Windows v my Ubuntu - my Windows: IP address: Subnetmask: 192.168.1.153 255.255.255.0

Default gateway: 192.168.1.1 - my Ubuntu: Trong terminal g lnh sudo gedit /etc/network/interfaces, chng trnh yu cu bn nhp password, nhp vo password ca user ang s dng.

Ca s File Interfaces s c m vi trnh son tho Gedit: ta s g a ch ip ca my Ubuntu ti y nh sau:

auto eth0 iface eth0 inet static address 192.168.1.152 netmask 255.255.255.0 gateway 192.168.1.1 Sau bm nt Save li v trong terminal g lnh sudo etc/init.d/networking restart khi ng li Networlk. Vy l xong bn thit lp ip cho my Ubuntu.-

S dng cng c Xshell trn Windows Start -> Programs -> Xmanager Enterprise -> Xshell. Giao din ca Xshell nh hnh sau:-

Giao din Xshell Hp thoi New Session Properties Chn File->), xut hin hp thoi New Session Properties. Trn hp thoi ny, mc General g tn session vo Name, IP vo Host v chn Protocol l SSH. Sau click chut vo mc Authentication.-

Hp thoi New Session Properties Authentication - Trong mc Authentication, chn Method l Password, sau nhp username/password ng nhp Ubuntu. Click nt OK kt thc vic to mt session mi. Khi s xut hin hp thoi Sessions c lu cc thng tin v cc session c to.

Hp thoi Sessions ca Xshell

- Trn hp thoi Sessions, la chn session cn thit, sau click nt Connect. Khi Xshell s kt ni n Ubuntu c a ch IP trn. S xut hin hp thoi SSH Security Warning nh hnh di.

Hp thoi SSH Security Warning - Trn hp thoi SSH Security Warning, click nt Accept & Save lu li host key xc thc vic kt ni. Qu trnh kt ni thnh cng, trn ca s ca Xshell s c th g cc lnh trn Ubuntu .

Xshell Kt ni thnh cng n mt Linux Server Ch : Cng c Xshell cho php chy mt s chng trnh c giao din ha ca Ubuntu trn Windows thng qua X11 Forwarding. Ti ca s lnh, c th g lnh chy chng trnh ny. V d c th chy cc chng trnh nh gedit, gnomecommander. Tnh nng ny cng h tr ngi dng thun tin hn khi iu khin, qun tr.-

Gnome Commander hin th trn Windows thng qua Xshell

S dng cng c Putty trn windows

- So vi Xshell th cng c Putty l cng c gn nh, min ph v ch bao gm 1 file chy duy nht. Chy chng trnh Putty, xut hin hp thoi Putty Configuration:

Hp thoi Putty Configuration

- Trn hp thoi Putty Configuration, mc Session, nhp cc gi tr: o Host Name (or IP address): Nhp IP ca Ubuntu. o Connection type: Chn giao thc SSH. o Saved Session: Nhp tn ca Session kt ni. d nh, c th s dng tn session l a ch IP ca my kt ni n. Sau khi nhp tn session, nhp nt Save lu li

thng tin v session . Xut hin ca s lnh yu cu ln lt xc nhn: - login as: user name trn my Linux. - Password: mt khu tng ng. Sau khi xc nhn cc thng tin trn, Putty s login vo Ubuntu v xut hin ca s lnh cho php thc hin cc lnh trn Ubuntu.

Ca s lnh ca Putty

Kt hp cc th mc remote trong Ubuntu s dng giao thc SSH

Chn Places -> connect to server:

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Trong cc ca hp thoi connect to server :o o o o

Service type: chon dch v l SSH. Server : 192.168.1.152 Folder:/home/tieusumo3 User Name: tieusumo3

o Bookmark name: Work Sao bm connect.

Do chng ta s dng SSH, cho nn h thng s hin th thng bo kt ni ti server. Bm nt Log In Anyway.-

in mt khu xc nhn, c 3 quyn la chn

- Khi thc hin xong bn s thy ng dn xut hin trn desktop, kch p vo truy cp d liu chia s trn h thng:

- Nhng l chng ta thc hin bng cc cng c c giao din, i

vi dng lnh th :

V bn cht, cc d liu remote kt hp s c tm thy trong ~/.gvfs/ (trong ~ l shortcut ca th mc gc s c dng /home/). di chuyn ti v tr , m ca s Terminal (Applications/ Accessories/ Terminal) v g lnh sau:

cd ~/.gvfs/ in tham s ls s lit k ra tt c nhng th mc cha d liu c th kt hp (g 1 vi k t nhn din ban u ri g tab hin th tt c):