November 2002 - openSUSE Security - openSUSE Mailing Lists

AW: [suse-security] SuseFirewall2 DMZ
by Ulrich Roth 19 Nov '02

19 Nov '02

> Proftd running becouse i have the log message of proftpd > > --- Togan Muftuoglu <toganm(a)users.sourceforge.net> a écrit : > > * FrÃ©dÃ©ric Poulet; > <pofrederic(a)yahoo.fr> on 14 Nov, 2002 wrote: > > >when i use ftp service from firewall i have logs: > > >Jan 23 12:40:11 linux kernel: SuSE-FW-REJECT IN=eth2 OUT= > > >MAC=00:40:f4:3d:89:4b:00:e0:18:a6:7d:17:08:00 > SRC=192.168.5.2 DST=192.168.5.1 LEN=60 TOS=0x00 > > >PREC=0x00 TTL=64 ID=55868 DF PROTO=TCP SPT=32983 DPT=113 > WINDOW=5840 RES=0x00 SYN URGP=0 OPT > > >(020405B40402080A0430C8600000000001030300) I think the following happens: You start an ftp request to your server (your web server I think). Before your server answers, it tries to find out who the client machine is, and sends therefore an auth request to the client. But the firewall blocks this auth request. Normally the ftp connection should be established, although the auth request isn't answered. But it may take quite long. Best is to open your firewall for auth requests. The other possibility is to enter your client into the server's /etc/hosts, but in your case I think it may not be possible because of the masquerading, so the ftp requests from different clients all seem to come from the same IP address. Hmm... Simply try entering the IP address 192.168.5.1 in the server's /etc/hosts with some host name you like. Maybe it works. Bye Uli -- Ulrich Roth IMPACT Business & Technology Consulting GmbH Im Mediapark 8 / KölnTurm D-50670 Koeln Phone +49-221-93 70 80-29 Fax +49-221-93 70 80-15 E-Mail: roth(a)impact.de

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Modify Seccheck behaivor
by Linux User 19 Nov '02

19 Nov '02

Hi guys... I install seccheck on my suse email server.. and it seems that one of it's security test it check for weakness passwords, and send to the users an email with something like: Your password for account "account_name" is insecure. > Please change it as soon as possible. > > Yours, > Password Checking Robot How could I stop that process to send an email to each user ? Thanks !! bye --ed

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Kernel 2.4.19 + e1000 module
by Drew J. Como 19 Nov '02

19 Nov '02

All, On one of my systems, I need to build a custom kernel with some special security modules built in (which I have already completed) and want to build in support for the Intel 1000 Gigabit cards. Has anyone successfully done this? I have downloaded the sources from Intel, but they are not providing any support nor instructions for them. Any help that can be given, I would appreciate. ============================================ Drew J. Como Phone: 631-434-6600 Systems Administrator Fax: 631-434-7800 dcomo(a)bascom.com Web: www.bascom.com Bascom Global Internet Services, Inc. -------------------------------------------- "When quality is the goal, winning is guaranteed."

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Masquerading trouble
by Jostein Berntsen 18 Nov '02

18 Nov '02

Hi, I have got some masquerading trouble now when I upgraded from 8.0 to 8.1. I have got a main PC as a name server, and 2 other PC's connected to this. Masquerading worked perfectly with DNS and Bind9 in 8.0, but when I upgraded I get these errors when trying to reach the Internet from the other PC's: 1. Command Dig ; <<>> DiG 8.3 <<>> 195.159.1.208 1 ;; res options: init recurs defnam dnsrch ;; res_nsend to server default -- 192.168.100.1: Connection refused 2. Command SuSEfirewall2 Try `iptables -h' or 'iptables --help' for more information. Bad argument `reject_func' 3. rejec_func is: Chain reject_func (1 references) target prot opt source destination REJECT tcp -- anywhere anywhere reject-with tcp-reset REJECT udp -- anywhere anywhere reject-with icmp-port-unreachable REJECT all -- anywhere anywhere reject-with icmp-proto-unreachable - Ping hangs at 56(84) bytes of data - Bind version is bind9-9.1.3-252 Dial-up Internet works fine from the gateway PC, and all PC's can be pinged internally with both IP and host name. SuSEFirewall2 is activated, and FW_MASQUERADE is set to yes, as is IP_FORWARD to yes in /etc/sysconfig/sysctl. Named.conf, zones, /etc/hosts, and /etc/resolv.conf is configured. Can anyone help with this? Regards, Jostein

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AW: [suse-security] SSH Authentication
by Ulrich Roth 18 Nov '02

18 Nov '02

> I implemented a ssh conection from the outside to my > intranet. This ssh requires a username and a password. > > In terms of security what is more secure: require > authentication (username and password) or having the public > key of each user that connects to our intranet in the > authorized public key lists (in this case there is no need > for username and password)? > In the second case there is no need of authentication and > only the users wich have the public keys in the list are > allowed to enter in my intranet. That's not true. If someone doesn't have the private key belonging to a certain public key in the list, he is asked for the password. Or is it possible to configure a remote computer in such a way that it doesn't give you a login prompt any more if there exists a public key? > This second solution is a good solution or that brings other > security problems ? The solution with the keys is less secure than the one with passwords, of course. If Computer A connects to computer B via SSH, and there exists a pair of keys so that you don't have to enter the password, then a hacker who logged into computer A has also free access to computer B (crack one, access two). If there's no real need for a pair of keys (e.g. if a cron job copies files from A to B), then you shouldn't use that. Bye Uli

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Re: Fw: [suse-security] Request of servers wins and servers dns, By VPN PPTP
by Fabio Sena 18 Nov '02

18 Nov '02

Gentlemen, Good Night gentlemen, Favours the tips of the gentlemen I obtained, to make a Server VPN in SuSE with PPTP, already I obtain the VPN, only that when I receive the IP from creaks it specified in the VPN server, I do not obtain to make nothing, Therefore my request of ms-dns, ms-wins is DROPs for the FW, for Anti-spoofing, some of the gentlemen knows as I can decide this? In mine opitions.pptp, is with the options of ms-dns and ms-wins, is necessary? or the Client Vpn would assume this automatically? Fabio Sena Brasil-PE My configuration in pptpd.conf debug localip 10.10.40.250 My ip address in eth1(internal lan) remoteip 10.10.40.251-254 listem 200.xxx.xxx.xxx My ip address in eth0(external) My configuration in options.pptp name fwpro.cyberland.com.br lock mtu 1490 mru 1490 proxyarp noauth -chap -chapms +chapms-v2 #chapms-strip-domain ipcp-accept-local ipcp-accept-remote lcp-echo-failure 5 lcp-echo-interval 8 deflate 0 mppe-128 mppe-stateless require-chap #require-mppe #require-mppe-stateless debug -detach proxyarp asyncmap 0 mppe-stateless ms-wins 10.10.30.2 ms-dns 200.249.140.2 netmask 255.255.0.0 When I am Loged in Way pptp in the Vpn server, I am receiving these messages from the SuSEfirewall2, Exactly stopping the SuSEfirewall2, come across myself with these messages. Nov 18 11:01:25 fwpro kernel: SuSE-FW-UNAUTHORIZED-TARGET IN=ppp0 OUT= MAC= SRC=10.10.40.252 DST=255.255.255.255 LEN=96 TOS=0x00 PREC=0x00 TTL=128 ID=1165 PROTO=UDP SPT=137 DPT=137 LEN=76 Nov 18 11:01:28 fwpro kernel: SuSE-FW-DROP-ANTI-SPOOF IN=ppp0 OUT= MAC= SRC=10.10.40.252 DST=255.255.255.255 LEN=96 TOS=0x00 PREC=0x00 TTL=128 ID=1175 PROTO=UDP SPT=137 DPT=137 LEN=76 Nov 18 11:01:30 fwpro kernel: SuSE-FW-UNAUTHORIZED-TARGET IN=eth0 OUT= MAC=00:90:27:75:b5:8d:00:10:7b:00:63:94:08:00 SRC=200.249.140.58 DST=200.249.140.20 LEN=129 TOS=0x00 PREC=0x00 TTL=126 ID=1564 PROTO=47 Nov 18 11:01:38 fwpro pppd[10483]: sent [CCP ConfReq id=0x3] Nov 18 11:01:46 fwpro kernel: SuSE-FW-UNAUTHORIZED-TARGET IN=eth0 OUT= MAC=00:90:27:75:b5:8d:00:10:7b:00:63:94:08:00 SRC=200.249.140.58 DST=200.249.140.20 LEN=129 TOS=0x00 PREC=0x00 TTL=126 ID=1566 PROTO=47 in the SuSEfirewall2 mine config # Common: smtp domain FW_SERVICES_EXT_TCP="110 1723 53 ssh" # Common: domain FW_SERVICES_EXT_UDP="137 53 500" # Common: domain # For VPN/Routing which END at the firewall!! FW_SERVICES_EXT_IP="gre 47" # # Common: smtp domain FW_SERVICES_DMZ_TCP="" # Common: domain FW_SERVICES_DMZ_UDP="" # For VPN/Routing which END at the firewall!! FW_SERVICES_DMZ_IP="" # # Common: ssh smtp domain FW_SERVICES_INT_TCP="53 42 135:139 1723 5800 5900" # Common: domain syslog FW_SERVICES_INT_UDP="42 53 135:139" # For VPN/Routing which END at the firewall!! FW_SERVICES_INT_IP="47 gre" On Mon, 2002-11-18 at 04:35, Fabio Sena wrote: > > ----- Original Message ----- > From: "Fabio Sena" <skill(a)cyberland.com.br> > To: <suse-security(a)suse.com> > Sent: Thursday, November 14, 2002 6:21 PM > Subject: [suse-security] Request of servers wins and servers dns, By VPN > PPTP > > > > Good Night gentlemen, > > > > Favours the tips of the gentlemen I obtained, to make a > Server > > VPN in SuSE with PPTP, already I obtain the VPN, only that when I receive > > the IP from creaks it specified in the VPN server, I do not obtain to make > > nothing, Therefore my request of ms-dns, ms-wins is DROPs for the FW, for > > Anti-spoofing, some of the gentlemen knows as I can decide this? > > In mine opitions.pptp, is with the options of ms-dns and > > ms-wins, is necessary? or the Client Vpn would assume this automatically? > > > > > > Fabio Sena > > Brasil-PE > > > > > > -- > > Check the headers for your unsubscription address > > For additional commands, e-mail: suse-security-help(a)suse.com > > Security-related bug reports go to security(a)suse.de, not here > > > > > >

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after HARDEN_SUSE Xsession: login for <user> is disabled ??
by Linux User 18 Nov '02

18 Nov '02

Hi guys... I just have test the HARDEN_SUSE and when I try to login on KDE as Oracle user I get the following error: Xsession: login for oracle is disabled Any clue of how to enable it ? Thanks bye --ed

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SSH Authentication
by Joao Reis 18 Nov '02

18 Nov '02

Hi! I implemented a ssh conection from the outside to my intranet. This ssh requires a username and a password. In terms of security what is more secure: require authentication (username and password) or having the public key of each user that connects to our intranet in the authorized public key lists (in this case there is no need for username and password)? In the second case there is no need of authentication and only the users wich have the public keys in the list are allowed to enter in my intranet. This second solution is a good solution or that brings other security problems ? Thanks. -- Farewell. "Keep your friends close, but your enemies closer." "Do or do not. There is no try" - Yoda João Reis -------------------------------------------------------

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RE: [suse-security] allow VPN (pp2p) through firewall
by Patrick Ofner 18 Nov '02

18 Nov '02

Ok, thanks! But I think with kernel 2.2.18 (and so ipchains, not iptables!) there might be a problem with protocoll 47 ?! And do I really not need INPUT and OUTPUT chains (this is with ipchains a little bit different as with iptables)? Bye, Patrick Ofner -----Original Message----- From: Alex Bartl [mailto:alex@bartl.net] Sent: Montag, 18. November 2002 03:28 To: Patrick Ofner; suse-security(a)suse.com Subject: AW: [suse-security] allow VPN (pp2p) through firewall iptables -p 47 -A FORWARD -s 0/0 -d xx.xx.xx.xx -j ACCEPT iptables -p 47 -A FORWARD -s xx.xx.xx.xx -d 0/0 -j ACCEPT iptables -p 6 -A FORWARD -s 0/0 -d xx.xx.xx.xx --destination-port 1723 -j ACCEPT iptables -p 6 -A FORWARD -s xx.xx.xx.xx --source-port 1723 -d 0/0 -j ACCEPT should be fine, whereas xx.xx.xx.xx is the VPN Server, behind your firewall. Make sure, you have no blocking rules which might capture those packages before reaching these rules, or use -I (insert) instead of -A (append). - mfg Alex Bartl Computer ALEX Bartl OEG AB1518-RIPE (whois.ripe.net) AB527363-NICAT (whois.nic.at) AB2092 (whois.networksolutions.com) *********************************** Hamerlingstrasse 2/201 4020 Linz http://www.bartl.net > -----Ursprungliche Nachricht----- > Von: Patrick Ofner [mailto:ofner_pa@koeflach-tv.at] > Gesendet: Samstag, 16. November 2002 14:25 > An: suse-security(a)suse.com > Betreff: [suse-security] allow VPN (pp2p) through firewall > > > Hi, > > I want to connect two windows boxes through a vpn (pp2p), but between > them there is a Linux firewall (kernel 2.2.18 , ipchains). What rules > must i create? >

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AW: [suse-security] which users
by Ulrich Roth 18 Nov '02

18 Nov '02

> > suse 7.3 > > I got a unfamiliar mail for localhost: > > what is the best way to check which users are logged on? > You can check using the "w" or "who" command. > This only includes shell users (ssh, telnet). Users logged in > via pop3, > imap or web (http auth) can be traced using the appropriate logfiles > (/var/log/messages, /var/log/httpd/access_log) Try also the "last" command. -- Ulrich Roth IMPACT Business & Technology Consulting GmbH Im Mediapark 8 / KölnTurm D-50670 Koeln Phone +49-221-93 70 80-29 Fax +49-221-93 70 80-15 E-Mail: roth(a)impact.de

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