Amint l�thatod el�g egyszer� a nyelvhaszn�latom, mert az angol nem az anyanyelvem. Ezt a dokumentumot angolul �rom a Linux-k�z�ss�g haszn�ra. Sz�val, bocs�ss�tok meg angol haszn�latom egyszer�s�g�t, �s amennyiben besz�lsz portug�lul akkor azon a nyelven �rj nekem levelet
Ez dokumentum azt igyekszik bemutatni neked (�s magamnak), hogy mik�nt �p�ts�nk olyan Linux �tj�r�t vagy t�zfalat, mely k�r�sre m�dos�tja a szab�lyokat, amikor a felhaszn�l�k be- illetve kijelentkeznek saj�t Windows munka�llom�sukr�l.
Kellene �rnom egy alkalmaz�st, de t�l lusta vagyok. Rem�lem, ha az �tlet eljut m�sokhoz, akkor valakik majd k�sz�tenek p�r intelligensen be�p�tett csomagot. Addig pedig...
A dokumentumban megpr�b�lom megmutatni, hogy mik�ppen �p�ts�nk �tj�r�t NAT-hoz vagy �lc�zott (MASQUERADE) Windows munka�llom�sokhoz. Haszn�ld a k�pzel�er�d a m�dos�t�sokhoz, a k�l�nb�z� h�l�zatkezel�si szintek megval�s�t�s�hoz. Haszn�lhatod szolg�ltat�sokhoz, szerverekhez vagy alh�l�zatokhoz t�rt�n� hozz�f�r�s enged�lyez�s�re vagy tilt�s�ra.
K�pzeld el, hogy �p�tened kell egy �tj�r�t a Windows munka�llom�said internet-hozz�f�r�s�nek biztos�t�s�ra, �s el�tte neked kell hiteles�teni minden felhaszn�l�t. Az els� megold�s ami eszedbe jut az a Squid. Ez csakugyan nagyszer� megold�s, amennyiben a felhaszn�l�idnak el�g a http �s az ftp hozz�f�r�s. Amikor sz�ba ker�l, hogyan f�rhetnek hozz� egy�b szolg�ltat�sokhoz is, mint pop, smtp, adatb�zis szerver vagy b�rmi m�s, azonnal a NAT �s MASQUERADE jut eszedbe. De mi t�rt�nik a felhaszn�l�i hiteles�t�ssel?
Nos, ez az �n megold�som, mely lehet�s�get ad a felhaszn�l� hiteles�t�s�re �s finombe�ll�t�s�ra amikor a k�ls� h�l�zathoz kapcsol�dik.
Mint tudjuk a SAMBA k�pes Domain vez�rl�k�nt m�k�dni, �s �gy hiteles�teni a felhaszn�l�kat a Windowsokr�l. Mint PDC a SAMBA k�pes v�grehajtani a Windows munka�llom�sok bejelentkez�si szkriptjeit. Fel tudjuk haszn�lni ezeket a h�l�zati bejelentkez�-szkripteket annak k�nyszer�t�s�re, hogy Windows munka�llom�sainkat hozz�kapcsol�djanak a Linux PDC megadott megoszt�s�hoz. Ez a k�nyszer�tett megoszt�s fogja tartalmazni azokat az el�tte- �s ut�lag futtatand� szkripteket, amelyek a felhaszn�l� ki- vagy bejelentkez�sekor hajt�dnak v�gre. Az smbstatus (ez a SAMBA r�sze - a ford.) program kilist�zza a haszn�latban l�v� megoszt�sokat, ki�rja a felhaszn�l� nev�t �s a munka�llom�s IP c�m�t is. Csak meg kell sz�rn�nk az smbstatus kimenet�t �s aktualiz�lni a t�zfal szab�lyokat.
A dokumentum tartalma minden k�telezetts�g n�lk�l felhaszn�lhat�. Haszn�ld az elvet, p�ld�t �s egy�b tartalm�t saj�t felel�ss�gedre. Mivel ez a leg�jabb v�ltozat, lehetnek benne hib�k, t�ved�sek, amelyek k�ros�thatj�k a rendszeredet. Haszn�ld nagy figyelemmel �s b�r nagyon szomor�, de a szerz�(k) semmilyen felel�ss�get nem v�llalnak �rte.
Minden szerz�i jogot a megfelel� tulajdonos birtokol, hacsak m�sk�nt nincs jelezve. Ebben a dokumentumban haszn�lt szakkifejez�seknek az �rv�nyess�gi vonatkoz�sa nem kell tekintettel legyenek semmilyen v�djegynek vagy szerviz m�rk�nak.
Az egy�ni term�kekre vagy m�rk�kra t�rt�n� hivatkoz�s nem szab�lys�rt�s.
A leg�jabb v�ltozat megtal�lhat� a http://ram.eti.br vagy a http://www.tldp.org webhelyen.
A kapcsol�d� HOGYANok megtal�lhat�k a Linux Documentation Project webhely�n; http://tldp.org. (Illetve a Magyar LDP webhely�n - a lektor.)
Portug�l verzi� hozz�f�rhet�.
A francia v�ltozat Guillaume Lelarge ford�t�s�ban megtal�lhat� a http://www.traduc.org honlapon.
A magyar v�ltozat megtal�lhat� a http://tldp.fsf.hu honlapon.
Ha seg�teni szeretn�l egy ford�t�ssal, akkor k�rlek tedd.
Mindenf�le k�zrem�k�d�st illetve b�r�latot sz�vesen fogadok.
Az angol nyelvezet jav�t�s�val kapcsolatos �szrev�teleket is sz�vesen veszem!
Ha b�rmilyen hib�t fedezel fel a dokumentumban tal�lhat� szkriptekben, k�rlek �rtes�ts.
Megtal�lsz a [email protected] vagy [email protected] e-mail c�men.
Copyright (c) 2002-2003 Ricardo Alexandre Mattar
A dokumentum m�sol�sa, terjeszt�se �s/vagy m�dos�t�sa enged�lyezett a Free Software Foundation (Szabad Szoftver Alap�tv�ny) �ltal k�zz�tett GNU Free Documentation License 1.2 vagy k�s�bbi v�ltozat�ban le�rt felt�telek szerint; �lland� fejezetek, el�oldali �s h�toldali sz�vegek n�lk�l. A licenc egy m�solata megtal�lhat� a "GNU Free Documentation License" fejezetben.
K�sz�net Carlos Alberto Reis Ribeironak, hogy megmutatta nekem a Linuxot.
K�sz�net Cesar Bremer Pinheironak, hogy motiv�lt ezen dokumentum meg�r�s�ra.
K�sz�net Guillaume Lelargenak az �tdolgoz�sn�l ny�jtott (folyamatos) seg�ts�g�rt.
K�sz�net Erik Esplundnak a tov�bbi nyelvi korrekci�k�rt.
K�sz�net Albert Teixidsnek a k�d t�k�letes�t�s��rt.
K�sz�net Felipe Cordeiro Caetanonak, ami�rt seg�tett a teszthelyem elk�sz�t�s�ben.
K�sz�net a RASEAC kommunik�ci�s biztons�ggal foglalkoz� c�gnek, ami�rt t�mogatja munk�mat.
A magyar ford�t�st Kormos Gy�rgy k�sz�tette (2003.12.16). A lektor�l�st Daczi L�szl� v�gezte el (2003.12.23). Utolj�ra friss�tve 2004.05.24.-�n. A dokumentum legfrissebb v�ltozata megtal�lhat� a Magyar Linux Dokument�ci�s Projekt honlapj�n.
Ez a dokumentum a tapasztalt rendszer-adminisztr�torokat c�lozza meg.
El�g j� tud�sod kell legyen (nem utols� sorban tudd, hogy mik ezek):
Szerencs�re b�s�ges dokument�ci� tal�lhat� ezekb�l az Interneten.
Legal�bb ezek legyenek telep�tve a szerveren:
Ez a HOGYAN felt�telezi, hogy van egy RENDSZERMAGOD a 2.4-es sz�ri�b�l ami haszn�lja az IPTable szolg�ltat�st. Azonk�v�l nincsenek ismert fejlem�nyek mi�rt ne m�k�dj�n ez egy 2.2 rendszermagon azokkal a scriptekkel, amik az IPChains-hez lettek haszn�lva.
Term�szetesen telep�tened kell az iptables userland eszk�zt, egy apache http szervert, ha CGI eszk�zt szeretn�l futtatni a jelsz�cser�hez �s SAMBA-hoz. Sz�ks�ged lesz egy olyan rendszermagra, amelyhez az iptables modul le lett ford�tva.
K�v�ns�g szerint haszn�lhatsz DHCP-t. Ez esetben k�nny� a be�ll�t�sa. Ne felejtsd el a dhcp szerveren be�ll�tani, hogy szolg�ltassa a n�vszerver IP c�m�t �s az �tj�r��t is. A windowsos g�pek nagyon j�l haszn�lj�k ezeket az inform�ci�kat.
�ltal�nosan elmondhat�, hogy a legt�bb alapbe�ll�t�s a k�l�nb�z� Linux-terjeszt�sekben megegyezik, �s illeszkednek ehhez az �tj�r� p�ld�hoz. Csak ellen�rizd le, ha van Samb�d �s IPTABLES-ed.
A kieg�sz�t� tartalomjegyz�k-hierarchia sz�ks�ges lesz az ebben a HOGYANban tal�lhat� p�lda megval�s�t�s�hoz.
Ezek haszn�latosak a felhaszn�l�k �s az IP c�mek nyomon k�vet�s�re:
/var/run/smbgate/
A felhaszn�l�f�gg� szkriptek k�nyvt�ra:
/etc/smbgate/users/
A csoportf�gg� szkriptek k�nyvt�ra:
/etc/smbgate/groups/
Megosztott k�nyvt�r a bejelentkez�shez:
/home/samba/netlogon/
A nyomk�vet�s megoszt�sa:
/home/samba/samba/
Ez a k�nyvt�rrendszer sz�ks�ges, hogy a p�ld�ban szerepl� szkriptek �s d�monok m�k�djenek.
Nagyon val�sz�n�tlen, hogy az �ltalad haszn�lt Linux-terjeszt�sbe ne lenne beleford�tva az iptables, vagy �ppen nem lenn�nek telep�tve a felhaszn�l�i eszk�z�k. Mindenesetre, ha ezek nincsenek, akkor a programok �s dokument�ci�k beszerz�s�hez utal�sokat tal�lsz a http://www.netfilter.org vagy http://www.iptables.org webhelyen.
Sz�ks�ged lesz az alapvet� t�zfal be�ll�t�sokra az �tj�r�d m�k�d�s�hez. N�zd meg az iptables k�zik�nyv�ben: IPTABLES TUTORIAL. Nagyon �rdekes olvasm�ny. Egy�bk�nt, ha nincs id�d az olvas�sra, a k�vetkez� k�d el�g� �ltal�nos ahhoz, hogy megfeleljen a sz�ks�gleteidhez.
#!/bin/sh IPTABLES=/usr/sbin/iptables /sbin/depmod -a /sbin/insmod ip_tables /sbin/insmod ip_conntrack /sbin/insmod ip_conntrack_ftp /sbin/insmod ip_conntrack_irc /sbin/insmod iptable_nat /sbin/insmod ip_nat_ftp echo "1" > /proc/sys/net/ipv4/ip_forward echo "1" > /proc/sys/net/ipv4/ip_dynaddr $IPTABLES -P INPUT ACCEPT $IPTABLES -F INPUT $IPTABLES -P OUTPUT ACCEPT $IPTABLES -F OUTPUT $IPTABLES -P FORWARD ACCEPT $IPTABLES -F FORWARD $IPTABLES -t nat -F
Mint l�thatod, ez a k�d val�j�ban nem csin�l semmit. Eredm�nyek�ppen m�gis bet�lt�dnek a NAT �s t�zfalhaszn�lat moduljai, valamint bekapcsolja a csomag �tvonal kijel�l�st. Elhelyezheted (el k�ne helyzened) azokat a szab�lyokat, melyek meghat�rozz�k az �tj�r�d alapvet� viselked�s�t. A "nagy var�zslat" (big magic) a SAMBA d�mon �ltal lefuttatott szkriptekkel lesz befejezett.
Figyelj! Eml�keztetlek, hogy ez a k�d a legkev�sb� sem biztons�gos! Ne haszn�ld ezeket a p�ld�kat m�k�d� rendszerekben. Ezek a p�ld�k csak oktat�si c�llal k�sz�ltek. Neked kell a rendszerednek legjobban megfelel� t�zfalszab�lyokat be�ll�tanod
Figyelmeztetettelek!
Ellen�rizd, hogy a SAMBA telep�tve legyen. Ha a te Linux-terjeszt�sed nem tartalmazza a SAMBA csomagot, akkor n�zz k�r�l a http://www.samba.org webhelyen. Innen beszerezheted a csomagot, valamint tal�lsz �tmutat�t a telep�t�sr�l is. N�zz k�r�l ezeken a weblapokon �s tanulj bel�l�k. A webhelyen sok dokument�ci� tal�lhat�. Val�sz�n�leg a te Linux-terjeszt�sed is b�s�ges SAMBA dokument�ci�t tartalmaz.
A SAMBA csomagot els�dleges domain vez�rl�nek (Primary Domain Controller) kell be�ll�tanod. Itt tal�lhatsz egy be�ll�t�si p�ld�t, de sz�ks�ges a Samba HOWTO Collection dokument�ci�t �tolvas�sa, valamint tanulj meg mindent a PDC-r�l amit csak lehet.
Mivel nem szeretn�m �jra�rni a SAMBA dokument�ci�t, ez�rt �me egy p�lda smb.conf f�jl:
# �ltal�nos param�terek [global] workgroup = DOMAIN netbios name = LINUX server string = Linux PDC encrypt passwords = Yes map to guest = Bad Password passwd program = /usr/bin/passwd unix password sync = Yes max log size = 50 time server = Yes socket options = TCP_NODELAY SO_RCVBUF=8192 SO_SNDBUF=8192 add user script = /usr/sbin/useradd -d /dev/null -g 100 -s /bin/false -M %u logon script = netlogon.bat domain logons = Yes os level = 64 lm announce = True preferred master = True domain master = True dns proxy = No printing = lprng [homes] comment = Home Directories path = /home/%u read only = No [printers] comment = All Printers path = /var/spool/samba printable = Yes browseable = No available = No [netlogon] comment = NetLogon ShARE path = /home/samba/netlogon guest account = [samba] comment = login tracking share path = /home/samba/samba browseable = No root preexec = /usr/local/bin/netlogon.sh %u %I root postexec = /usr/local/bin/netlogoff.sh %u
Ezeket kell be�ll�tanod, vagy el kell olvasnod a SAMBA dokument�ci�t, ha val�ban fel�gyelni szeretn�d a szervered �s a h�l�zatod.
A netlogon megoszt�sb�l t�ltik le a Windows munka�llom�sok a bejelentkeztet� parancsf�jlokat. Az�rt van sz�ks�g�nk erre a megoszt�sra, hogy elhelyezz�k itt a bejelentkeztet� szkriptet. Ez jelzi a munka�llom�soknak, hogyan csatlakoztassanak egy megoszt�st, ahol a felhaszn�l�k IP c�mei lesznek k�vethet�k.
Amint l�thatod, sz�ks�ged lesz a smb.conf f�jlban a k�vetkez� bejegyz�sre is.
logon script = netlogon.bat
Ez a sor jelzi a Windows kliensednek, hogy t�ltse le �s futtassa a netlogon.bat szkriptet. Ennek a szkriptnek a netlogon megoszt�son kell lennie. Sz�val szint�n sz�ks�ged lesz egy netlogon.bat szkriptre a Windows munk�llom�sokhoz. Haszn�lhatod a k�vetkez� p�ld�t, elhelyezve a netlogon megoszt�son, ami ebben az esetben a: /home/samba/netlogon/NETLOGON.BAT.
REM NETLOGON.BAT net use z: \\linux\samba /yes
Ez a szkript fogja jelezni a Windows munka�llom�soknak, hogy csatlakoztass�k a megadott megoszt�sokat. Az smbstatus program kimenetei alapj�n pedig k�pesek lesz�nk nyomon k�vetni a felhaszn�l�t �s a munka�llom�st.
Eg�szen egyszer�! Azonban nem el�g...
Amint l�thatod, sz�ks�ged van m�g egy megoszt�sra (tracking share), amit - ebben a p�ld�ban - samba-nak neveztem. L�thatod a k�vet�s megoszt�s (tracking share) be�ll�t�sait az smb.conf f�jlban:
[samba] comment = login tracking share path = /home/samba/samba browseable = No root preexec = /usr/local/bin/netlogon.sh %u %I root postexec = /usr/local/bin/netlogoff.sh %u
Amint azt bizony�ra m�r kital�ltad vagy elolvastad a SAMBA dokument�ci�ban, a root preexec �s a root postexec sorok jelzik a SAMBA-nak, hogy futtasson egy javasolt szkriptet, amikor a felhaszn�l� fel- vagy lecsatol egy megoszt�st. Figyelj arra, hogy a %u a sorok v�g�n van. Ezek a szkriptek a "sz�rnyek" (beasts), melyek megh�vnak egy szkriptet, programot, hogy m�dos�ts�k az �tj�r�nk csomagsz�r� szab�lyait.
Figyelj, hogy a netlogon.sh szkriptnek ellen�riznie kell, hogy a hivatkozott munka�llom�s m�r csatlakoztatva van-e a nyomk�vet�s megoszt�s�hoz.
Vess egy pillant�st a netlogon.sh �s a netlogoff.sh szkriptekre:
#!/bin/sh
#
# netlogon.sh
#
# usage:
# netlogon.sh <username>
#
if [ -f /var/run/smbgate/$1 ] ; then
exit 0
fi
echo $2 > /var/run/smbgate/$1
IPTABLES='/usr/sbin/iptables'
EXTIF='eth0'
COMMAND='-A'
ADDRESS=`cat /var/run/smbgate/$1`
GROUP=`groups $1 | gawk '// { print $3 }'`
if [ -f /etc/smbgate/users/$1 ] ; then
/etc/smbgate/users/$1 $COMMAND $ADDRESS $EXTIF
else
if [ -f /etc/smbgate/groups/$GROUP ] ; then
/etc/smbgate/groups/$GROUP $COMMAND $ADDRESS $EXTIF
else
/etc/smbgate/users/default.sh $COMMAND $ADDRESS $EXTIF
fi
fi
A netlogon.sh szkript a felhaszn�l� bel�p�sekor hajt�dik v�gre. A v�grehajtand� szkript a felhaszn�l�i n�v �s a felhaszn�l� csoportja alapj�n ker�l kiv�laszt�sra. A felhaszn�l� IP c�me beker�l a /var/run/smbgate k�nyvt�rba nyomk�vet�si c�lb�l. A f�jl tartalmazza a felhaszn�l� nev�t, mely k�s�bb a kijelentkez�skor sz�ks�ges. Az IP c�m a felhaszn�l�i n�vvel egy�tt param�terk�nt ker�l �tad�sra, amely v�g�l friss�ti a t�zfalat.
Figyelj arra, hogy a netlogon.sh futtatni pr�b�lja a felhaszn�l� szkriptj�t. Ha nem tal�lja, akkor pr�b�lkozik a csoport szkripttel. V�g�l, ha nem tal�lja a csoport szkriptet sem, akkor a default.sh szkriptet futtatja. Ezt a logik�t �s viselked�st m�dos�thatod ha szeretn�d vagy sz�ks�ges, de ne felejtsd el m�dos�tani a t�bbit is ennek megfelel�en.
Val�sz�n�, ha a felhaszn�l� t�bb csoportba tartozik, akkor ezek a szkriptek hib�san fognak m�k�dni. Nem volt id�m jobb k�dot �rni.
#!/bin/sh
#
# netlogoff.sh
#
# usage:
# netlogoff.sh <username>
#
IPTABLES='/usr/sbin/iptables'
EXTIF='ppp0'
COMMAND='-D'
ADDRESS=`cat /var/run/smbgate/$1`
GROUP=`groups $1 | gawk '// { print $3 }'`
if [ -f /etc/smbgate/users/$1 ] ; then
/etc/smbgate/users/$1 $COMMAND $ADDRESS $EXTIF
else
if [ -f /etc/smbgate/groups/$GROUP ] ; then
/etc/smbgate/groups/$GROUP $COMMAND $ADDRESS $EXTIF
else
/etc/smbgate/users/default.sh $COMMAND $ADDRESS $EXTIF
fi
fi
rm -f /var/run/smbgate/$1
A netlogoff.sh szkript a felhaszn�l� kil�p�sekor fut le. A /var/run/smbgate/user f�jlb�l beolvasott c�m, mint argumentum �tad�dik az /etc/smbgate/users/user szkriptnek, amely friss�ti a t�zfalat �s vissza�ll�tja a felhaszn�l� bejelentkez�se el�tti �llapotot.
N�h�ny Windows verzi�, mint a Windows 2000 t�bbsz�r felcsatolja a nyomk�vet� megoszt�st. Ez probl�m�t okozhat az�ltal, hogy t�bbsz�r hajtja v�gre a netlogon.sh �s a netlogoff.sh szkripeket. Ez teljes z�rzavarhoz vezet. Nos, esetleg el�ny�sebb egy kil�p�s-ellen�rz�s (logout checking) futtat�sa cronb�l, mint a netlogoff.sh v�grehajtat�sa a SAMBA-val. �me egy p�lda:
#!/bin/sh
# checklogout.sh
#
# usage:
# intended to run at cron (maybe each 10 minutes)
TRACKDIR="/var/run/smbgate"
DIRLENGTH=${#TRACKDIR}
TRACKSHARE="samba"
EXTIF='eth0'
COMMAND='-D'
if [ -d $TRACKDIR ]; then
for n in $TRACKDIR/*; do
[ -d $n ] && continue;
if [ -f $n ] ; then
IPADDRESS=`cat $n`
USERNAME=${n:$DIRLENGTH+1}
NMS=`smbstatus -u $USERNAME | grep $TRACKSHARE | grep $IPADDRESS | grep -v grep | wc -l`
if [ $NMS == 0 ] ; then
rm -f $n
GROUP=`groups $USERNAME | gawk '// { print $3 }'`
if [ -f /etc/smbgate/users/$USERNAME ] ; then
/etc/smbgate/users/$USERNAME $COMMAND $IPADDRESS $EXTIF
else
if [ -f /etc/smbgate/groups/$GROUP ] ; then
/etc/smbgate/groups/$GROUP $COMMAND $IPADDRESS $EXTIF
else
/etc/smbgate/users/default.sh $COMMAND $IPADDRESS $EXTIF
fi
fi
fi
else
exit 0
fi
done
fi
Ebben az esetben el kell t�vol�tanod a postexec bejegyz�st az smb.conf nyomk�vet� megoszt�s�b�l:
root postexec = /usr/local/bin/netlogoff.sh %u
�me egy �ltal�nos /etc/smbgate/users/user szkript. Jelenleg ez az egyetlen, ami m�dos�tja a t�zfal szab�lyait.
#!/bin/sh # COMMAND=$1 ADDRESS=$2 EXTIF=$3 IPTABLES='/usr/sbin/iptables' $IPTABLES $COMMAND POSTROUTING -t nat -s $ADDRESS -o $EXTIF -j MASQUERADE
Az /etc/smbgate/users/ k�nyvt�rba szint�n kell egy default.sh szkript, hogy megadjuk az �tj�r� viselked�s�nek alapszab�lyait.
#!/bin/sh # # default.sh COMMAND=$1 ADDRESS=$2 EXTIF=$3 IPTABLES='/usr/sbin/iptables' #$IPTABLES $COMMAND POSTROUTING -t nat -s $ADDRESS -o $EXTIF -j MASQUERADE exit 0
Tal�n azt szeretn�d, hogy a PDC (Primary Domain Controller; els�dleges tartom�nyvez�rl�) egy g�pen fusson, egy m�sikon pedig egy �tj�r� (gateway), b�rmilyen okb�l. Ha �gy van, akkor az �tj�r�t �gy kell be�ll�tanod, hogy jelsz� n�lk�l elfogadja a PDC-r�l �rkezett, rsa kulccsal hiteles�tett bejelentkez�seket (login).
N�zd �t a www.openssh.org webhelyen l�v� dokument�ci�t az ssh szerver �s kliens helyes be�ll�t�s�hoz.
Az ssh dokument�ci�t el kell olvasnod. Bizonyosodj meg arr�l, hogy teljesen tiszt�ban vagy az rsa, illetve m�s titkos�tott azonos�t�ssal kapcsolatos teend�kkel
Ha a biztons�g nem fontos, akkor csak haszn�ld a p�ld�mat �s l�pj tov�bb.
Kulcsp�r l�trehoz�s�hoz a PDC-n a k�vetkez� parancsot haszn�ld:
pdc:~# ssh-keygen -t rsa
V�laszolj a k�rd�sekre, majd a l�trej�tt nyilv�nos kulcsot m�sold az �tj�r�ra. A nyilv�nos kulcs �ltal�ban a "~.ssh/id_rsa.pub" k�nyvt�rba ker�l.
pdc:~# cd .ssh pdc:~# scp id_rsa.pub root@gateway:/root/.ssh/authorized_keys2
K�vetkezzen egy m�dos�tott /etc/smbgate/users/user szkript, amely az ssh titkos�tott bejelentkez�st haszn�lja.
#!/bin/sh # COMMAND=$1 ADDRESS=$2 EXTIF=$3 IPTABLES='/sbin/iptables' ssh root@gateway $IPTABLES $COMMAND POSTROUTING -t nat -s $ADDRESS -o $EXTIF -j MASQUERADE
Figyeld meg, hogy a bin�ris iptables az ssh-n kereszt�l ker�l megh�v�sra a "gateway"-en. Megism�tlem, olvasd el az ssh szerver dokument�ci�j�t.
Be fogjuk �ll�tani a h�l�zatot, a felhaszn�l�k kezel�s�t �s a h�zirendet (policy) a windowsos munka�llom�sokon.
Nem fogok ezeken a l�p�seken teljesen v�gigmenni, megnevezni minden egyes p�rbesz�dablakot. Felt�telezem, hogy amennyiben el tudod olvasni �s meg�rted ezt a dokumentumot, akkor megtal�lod az utat az egyes l�p�sek k�z�tt.
El�sz�r is, hacsak val�ban nincs sz�ks�ged r�, akkor t�vol�ts el minden protokollt, kiv�ve a TCP/IP-t. A windowsos g�pek m�g a saj�t protokolljuk hi�ny�ban is szeretnek sokat �zengetni, �s ez nem mindenkinek tetszik. Egy�bk�nt is a TCP/IP-n k�v�l kinek kell b�rmi m�s?
Ha szeretn�l DHCP szervert a saj�t Linux rendszereden, ne feledd, hogy a Windows munka�llom�sok megkaphatj�k a n�vszerverek �s az �tj�r� c�m�t is a saj�t IP c�m�k�n fel�l. Sz�val nem kell minden munka�llom�son be�ll�tanod ezeket a jellemz�ket.
A Windows munka�llom�sokat Domain-be t�rt�n� bejelentkez�sre kell be�ll�tani. A Linux szervernek pedig �t kell adni a domain nevet. Ez alapvet�en sz�ks�ges az �tj�r� m�k�d�s�hez.
Tudnod kell! Ahhoz, hogy valamennyi windowsos verzi�s g�p be tudjon jelentkezni, a SAMBA domain vez�rl�h�z l�tre kell hoznod a g�pek fi�kjait a saj�t Linux PDC-den. (Amelyik nem tud feljelentkezni domain-be, az term�szetszer�leg nem: Win95, WinXP Home. - a ford.) N�zd meg a SAMBA le�r�st, hogy mik�ppen kell be�ll�tani a PDC-t az �ltalad haszn�lt Windowsokhoz.
Ezek a verzi�k �gy t�nik, hogy speci�lis be�ll�t�st ig�nyelnek a Linux PDC domain-be t�rt�n� bel�p�shez.
Ezen verzi�k eset�ben sz�ks�ges, hogy legyen a g�pnek fi�kja a Linux rendszerben. �jfent, n�zd meg a SAMBA le�r�s�t.
Ezen a verzi� eset�n sz�ks�ges, hogy legyen a g�pnek fi�kja a Linux rendszeren, �s egy kis m�dos�t�sra is sz�ks�g van a registry-ben.
Keresd meg a "HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Netlogon\Parameters\RequireSignOrSeal". kulcsot. Az alap�rt�k: 1, v�ltoztasd meg 0-ra. T�bbet nem fog panaszkodni a domain-be t�rt�n� bel�p�skor.
Ha sok munka�llom�sod van, melyeket be kell �ll�tanod, akkor k�sz�ts egy f�jlt. Legyen a neve anything.reg, amely a k�vetkez�ket tartalmazza. Haszn�ld ezt, a "hib�s" regisztr�ci�s bejegyz�sek m�dos�t�s�hoz.
Windows Registry Editor Version 5.00 [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Netlogon\Parameters] "requiresignorseal"=dword:00000000
Ezen verzi� eset�n szint�n sz�ks�ges egy kis m�dos�t�s a NETLOGON.BAT szkripten. N�mely esetben makacsul �s folyamatosan felcsatol�sokat v�gez.
REM NETLOGON.BAT net use z: \\linux\samba /yes /persistent:no
Ez egy kis seg�dprogram, amit a Windows CD-n megtal�lsz. A f�jl neve poledit.exe. Ez egy olyan eszk�z - mint a neve is sugallja -, mellyel felhaszn�l�i �s rendszer h�zirend-f�jlokat lehet k�sz�teni
Sajn�latos m�don ez az eszk�z nem k�pes sima sz�veges f�jlt k�sz�teni, �gy nem tudok itt p�ld�t bemutatni.
Haszn�ld a h�zirend szerkeszt�t munka�llom�sok �s felhaszn�l�k h�zirendjeinek elk�sz�t�s�hez. Le kell tiltanod a helyi �s domain jelsz� gyors�t�t�rat, a biztons�g n�vel�se �rdek�ben. T�rold el config.pol n�ven a h�zirend-f�jlt, �s helyezd el a netlogon megoszt�son. Ekkor a Windows munka�llom�said let�ltik �s haszn�lni fogj�k a config.pol f�jlt a saj�t h�zirendj�k be�ll�t�s�hoz. Term�szetesen ennek a sz�lnak a windowsos g�peken kell futnia.
Ha nem haszn�lsz config.pol f�jlt, a windowsos munka�llom�sok bosszantani fognak a Windows jelsz� bek�r�s�vel, �s meg�rj�tenek, amikor megpr�b�lod �sszhangba hozni �s kezelni a domain-odat �s Windows jelszavakat. �gy n�z ki, hogy az oper�ci�s rendszer nem tudja, hogy bel�pett egy domain-be. Ezt tudatnod kell vele, majd bele kell v�gnod az arc�ba, �gy hinni fog neked.
Linux-felhaszn�l� hozz�ad�s �s a samba jelsz� be�ll�t�sa az smbpasswd seg�ts�g�vel m�k�dik. Ha b�rmilyen k�ts�ged van, akkor olvasd el a SAMBA dokument�ci�t. Nem neh�z megcsin�lni.
�gy gondolom ez egy fontos t�ma, mert �n sem tanultam m�g meg, hogy mik�ppen kezelj�k a felhaszn�l�t �s a jelszav�t a Windows munka�llom�sokr�l a web-es fel�let haszn�lata n�lk�l. Nem tal�ltam �s nem tudom, hogy mik�ppen hozzak l�tre egy be�p�tett eszk�zt ezen probl�ma megold�s�ra. Nos, ez�rt �n egy CGI programot haszn�lok ennek megval�s�t�s�ra.
Pr�b�ld ki a http://changepassword.sourceforge.net webhelyr�l let�lthet� csomagot. Ez j� megold�snak t�nik.
Amint azt az el�z� fejezetekben l�thattad a SAMBA d�mon meg fogja h�vni a netlogon.sh szkriptet minden alkalommal, amikor a nyomk�vet� megoszt�s felcsatlakozik. Ez a netlogon.sh szkript fog megh�vni egy m�sik szkriptet a felhaszn�l� nev�vel �s a munka�llom�s IP c�m�vel, mint �tadott param�terrel. Ez a felhaszn�l�i szkript fogja be�ll�tani a k�v�nt szab�lyokat.
P�ld�ul, ha teljes hozz�f�r�st akarsz a felhaszn�l�nak az internethez, a k�vetkez�ket �ll�tsd be:
#!/bin/sh # COMMAND=$1 ADDRESS=$2 EXTIF=$3 IPTABLES='/usr/sbin/iptables' $IPTABLES $COMMAND POSTROUTING -t nat -s $ADDRESS -o $EXTIF -j MASQUERADE
Ha nem akarsz semmit sem megv�ltoztatni bizonyos felhaszn�l�k eset�ben, akkor k�sz�ts nekik egy �res szkriptet:
#/bin/sh # exit 0
Esetleg ne is k�sz�ts semmilyen szkriptet a kevesebb joggal rendelkez� felhaszn�l�knak. �gy �k a default.sh szkriptet kapj�k, mely ak�r �res is lehet mint az el�z� p�lda, vagy korl�tozott jogk�r�, mint lejjebb l�that�:
#!/bin/sh # COMMAND=$1 ADDRESS=$2 EXTIF=$3 EXTIFADDRESS=$4 IPTABLES='/usr/sbin/iptables' $IPTABLES $COMMAND POSTROUTING -t nat -s $ADDRESS -o $EXTIF --dport 25 -j SNAT --to-source $EXTIFADDRESS $IPTABLES $COMMAND POSTROUTING -t nat -s $ADDRESS -o $EXTIF --dport 110 -j SNAT --to-source $EXTIFADDRESS
Figyelj arra, hogy ezen szkript miatt m�dos�tanod kell az �sszes el�z� szkriptet, hogy tartalmazza az extra param�tereket, vagy egyszer�en csak m�dos�tsd ezt a szkriptet. Ne feledd azt sem, hogy nem m�sz ezzel a HOGYANnal semmire, ha nem �rted az iptables m�k�d�s�t.
Egyszer�en hozd l�tre a csoportot a Linux PDC-n, majd rendeld a felhaszn�l�kat az egyes csoportokhoz. Ez van.
Ne feledd azt a p�lda szkriptet ebben a HOGYANban, ami val�sz�n�leg hib�t eredm�nyez, ha egy felhaszn�l� t�bb csoportnak is a tagja. Ha szeretn�d (egy felhaszn�l� t�bb csoportba tartozhasson - a ford.), akkor ne felejtsd el a szkriptet megv�ltoztatni.
Csoportf�gg� szkripteket kell l�trehoznod �s elhelyezni �ket az "/etc/smbgate/groups/" k�nyvt�rban. Figyelj arra, hogy a f�jl nev�nek a csoport nev�t add, ha ennek a HOGYANnak a p�ld�j�t akarod k�vetni.
Ezen HOGYAN felfog�sa szerint el�sz�r ellen�rizd a felhaszn�l�i szkriptet, majd a csoport �s v�g�l az alap�rtelmezett szkriptet. Ha ezen alapviselked�sen m�dos�tani szeretn�l, akkor ne felejtsd el ehhez igaz�tani a netlogon.sh, netlogoff.sh (vagy checklogout.sh) szkripteket. Az eg�sz logik�ja ezekben a szkriptekben van.
Oskar Andreasson: IPTABLES TUTORIAL
The SAMBA Team: Samba HOWTO Collection
GNU Free Documentation License Version 1.2, November 2002
Copyright (C) 2000,2001,2002 Free Software Foundation, Inc. 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA Mindenki sz�m�ra enged�lyezett a dokumentum m�sol�sa r�szben vagy eg�szben, de annak tartalm�nak megv�ltoztat�sa nem megengedett.
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ADDENDUM: How to use this License for your documents
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