search for: prerouting

...-interface eth1 -j MASQUERADE #eth0 la interfaz de la red local iptables --append FORWARD --in-interface eth0 -j ACCEPT #activamos el forward echo 1 > /proc/sys/net/ipv4/ip_forward #reglas para enrutado de paketes... #1.- redirecciona las peticiones del puerto 21 a mi pc iptables -t nat -A PREROUTING -i eth1 -p tcp --dport 21 -j DNAT --to 192.168.0.16:21 iptables -t nat -A PREROUTING -i eth1 -p tcp --dport 143 -j DNAT --to 192.168.0.16:143 iptables -t nat -A PREROUTING -i eth1 -p tcp --dport 993 -j DNAT --to 192.168.0.16:993 iptables -t nat -A PREROUTING -i eth1 -p tcp --dport 995 -j DNAT --...

...t nat iptables -X iptables -X -t nat ############################################################################### ############################################################################### # aplicando as regras contra ataques de negacao de servico # contra ping of death # iptables -t nat -A PREROUTING -i eth1 -p icmp --icmp-type echo-request -m limit --limit 1/s -j ACCEPT # contra ataques syn-flood # iptables -t nat -A PREROUTING -i eth1 -p tcp -m limit --limit 1/s -j ACCEPT # contra port scanners avancados (nmap) # iptables -t nat -A PREROUTING -i eth1 -p tcp --tcp-flags SYN,ACK FIN,RST -m limi...

...riority: P5 Component: nft Assignee: pablo at netfilter.org Reporter: mskim128 at gmail.com I use Ubuntu 17.10 (nftables 0.8, kernel 4.13) NOTRACK is used to turn off connection tracking for all packets matching this rule. For example, in iptables: iptables -t raw -I PREROUTING -j NOTRACK I'd like to use stateless NAT (1:1)instead of iptables. nft add table NAT nft add chain NAT prerouting {type nat hook prerouting priority - 300 \; } nft add chain NAT postrouting {type nat hook postrouting priority - 300 \; } nft add rule NAT prerouting counter nft add rule NAT pr...

....21 flowid 1:13 tc filter add dev eth1 parent 1: protocol ip prio 1 handle 1 fw flowid 1:10 #we want interactive traffic here tc filter add dev eth1 parent 1: protocol ip prio 6 handle 2 fw flowid 1:14 #we want p2p traffic here #Sending the TOS-bits to the appropriate classes iptables -t mangle -A PREROUTING -m tos --tos Minimize-Delay -j MARK --set-mark 1 iptables -t mangle -A PREROUTING -m tos --tos Minimize-Delay -j RETURN iptables -t mangle -A PREROUTING -m tos --tos Minimize-Cost -j MARK --set-mark 2 iptables -t mangle -A PREROUTING -m tos --tos Minimize-Cost -j RETURN iptables -t mangle -A PREROU...

...disc add dev $eth parent 1:FE handle FE: sfq perturb 10 $tc filter add dev $eth parent 1: protocol ip prio 0 handle $metro fw flowid 1:FE done ---------------------------------------------------------------------------------------------------------------------- output of iptables-save (mangle PREROUTING): -A PREROUTING -p tcp -m tcp --sport 80 -j TOS --set-tos 0x10 -A PREROUTING -p tcp -m tcp --dport 80 -j TOS --set-tos 0x10 -A PREROUTING -p tcp -m tcp --dport 443 -j TOS --set-tos 0x10 -A PREROUTING -p tcp -m tcp --sport 443 -j TOS --set-tos 0x10 -A PREROUTING -p tcp -m tcp --sport 5050 -j...

...1 protocol ip parent 1:0 prio 4 handle 4 fw classid 1:13 tc filter add dev eth1 protocol ip parent 1:0 prio 5 handle 5 fw classid 1:14 tc filter add dev eth1 protocol ip parent 1:0 prio 6 handle 6 fw classid 1:15 #Se dan las reglas iptables para marcar lo que nos interesa $IPTABLES -t mangle -A PREROUTING -p icmp -j MARK --set-mark 0x1 $IPTABLES -t mangle -A PREROUTING -p icmp -j RETURN $IPTABLES -t mangle -A PREROUTING -m tos --tos Minimize-Delay -j MARK --set-mark 0x1 $IPTABLES -t mangle -A PREROUTING -m tos --tos Minimize-Delay -j RETURN $IPTABLES -t mangle -A PREROUTING -m tos --tos Minimize...

...o ppp1 -j ACCEPT -A OUTPUT -d 255.255.255.255 -o ppp0 -j ACCEPT -A OUTPUT -s ipofppp1 -o ppp1 -j ACCEPT -A OUTPUT -s ipofppp0 -o ppp0 -j ACCEPT -A OUTPUT -j LOG -A OUTPUT -j DROP COMMIT # Completed on Fri Nov 25 12:21:59 2005 # Generated by iptables-save v1.2.11 on Fri Nov 25 12:21:59 2005 *mangle :PREROUTING ACCEPT [13497:7096745] :INPUT ACCEPT [119515:10818662] :FORWARD ACCEPT [2263653:1380696494] :OUTPUT ACCEPT [3681:323141] :POSTROUTING ACCEPT [2445397:1397479483] -A PREROUTING -i ppp0 -m state --state NEW -j MARK --set-mark 0x1 -A PREROUTING -i ppp1 -m state --state NEW -j MARK --set-mark 0x2 -A PR...

...rent 1:0 protocol ip prio 1 handle 1 fw classid 1:10 tc filter add dev eth0 parent 1:0 protocol ip prio 2 handle 2 fw classid 1:20 tc filter add dev eth0 parent 1:0 protocol ip prio 3 handle 3 fw classid 1:30 Next I created some iptables rules for marking #Traffic for band #1 iptables -t mangle -A PREROUTING -p tcp --sport 22 -j MARK --set-mark 0x1 iptables -t mangle -A PREROUTING -p tcp --sport 22 -j RETURN iptables -t mangle -A PREROUTING -p tcp --sport 23 -j MARK --set-mark 0x1 iptables -t mangle -A PREROUTING -p tcp --sport 23 -j RETURN iptables -t mangle -A PREROUTING -p tcp --sport 21 -j MARK --s...

...l. In my iptables script, I need make 3 MARKs for the same packet, as following # It marks the packets that will go for link ADSL (I have 2 links - adsl 2Mb and ''dedicate link'' 256Mb ) # I am using ''ip rule / ip route'' to make this iptables -t mangle -A PREROUTING -p tcp --dport 21 -j MARK --set-mark 2000 iptables -t mangle -A PREROUTING -p tcp --dport 20 -j MARK --set-mark 2000 # It marks the packets that will be shapped ( upload with cbq ) iptables -t mangle -A PREROUTING -m mac 00:11:22:33:44:55 -j MARK --set-mark 501 .... iptables -t mangle -A PRE...

...htb rate 128kbit ceil 768kbit /sbin/tc class add dev imq1 parent 2:1 classid 2:20 htb rate 128kbit ceil 768kbit /sbin/tc filter add dev imq1 parent 2: protocol ip handle 10 fw classid 2:10 /sbin/tc filter add dev imq1 parent 2: protocol ip handle 20 fw classid 2:20 /usr/sbin/iptables -t mangle -A PREROUTING -i eth0 -j IMQ --todev 1 /usr/sbin/iptables -t mangle -A PREROUTING -i eth0 -j IMQ --todev 1 /usr/sbin/iptables -t mangle -A PREROUTING -i eth0 -d 202.x.1.0/24 -j MARK --set-mark 10 /usr/sbin/iptables -t mangle -A PREROUTING -i eth0 -d 202.x.2.0/24 -j MARK --set-mark 20 Please help me analyze...

Is there a way to add a rule to the nat table (CentOS 5.7) that would alter the port number of tcp packets destined for the server itself? I have ip_forwarding enabled, but the packets don't seem to hit the prerouting chain. I have the following redirect rule in the prerouting table. I also tried DNAT, but if the packets don't hit PREROUTING, it won't work either. iptables -t nat -L -v -n Chain PREROUTING (policy ACCEPT 16079 packets, 896K bytes) pkts bytes target prot opt in out source...

...) I suspected I just might not be marking things correctly, so I tried u32 matching 0.0.0.0/0 - that worked fine, but for _all_ traffic (as it should). So I tried marking *every* packet with $MARK_BULK (and verified that the mark was correct using a log match, and watching the syslog file) in both prerouting and postrouting chains, yet this didn''t help either. Regardless of what I do, I can''t get the above filter to match anything at all - I''m sure the packets are marked correctly, I just can''t match them. Any ideas? (I''ll copy my entire configs below for...

...irewall. In my iptables script, I need make 3 MARKs for the same packet, as following # It marks the packets that will go for link ADSL (I have 2 links - adsl 2Mb and ''dedicate link'' 256Mb ) # I am using ''ip rule / ip route'' to make this iptables -t mangle -A PREROUTING -p tcp --dport 21 -j MARK --set-mark 2000 iptables -t mangle -A PREROUTING -p tcp --dport 20 -j MARK --set-mark 2000 # It marks the packets that will be shapped ( upload with cbq ) iptables -t mangle -A PREROUTING -m mac 00:11:22:33:44:55 -j MARK --set-mark 501 .... iptables -t mangle -A PREROUTIN...

...-j ACCEPT iptables -A FORWARD -i ppp1 -p tcp -m tcp --dport 5000:5010 -j ACCEPT iptables -A FORWARD -i ppp1 -p tcp -m tcp --dport 15402 -j ACCEPT iptables -A FORWARD -i ppp1 -p udp -m udp --dport 15402 -j ACCEPT iptables -A FORWARD -i ppp+ -m state --state NEW,INVALID -j DROP iptables -t mangle -A PREROUTING -p icmp -m icmp -j TOS --set-tos Minimize-Delay iptables -t mangle -A PREROUTING -p tcp -m tcp --tcp-flags SYN,RST,ACK ACK -m length --length 0:128 -j TOS --set-tos Minimize-Delay iptables -t mangle -A PREROUTING -p tcp -m tcp --tcp-flags SYN,RST,ACK ACK -m length --length 128: -j TOS --set-tos...

...1 protocol ip parent 1:0 prio 4 handle 4 fw classid 1:13 tc filter add dev eth1 protocol ip parent 1:0 prio 5 handle 5 fw classid 1:14 tc filter add dev eth1 protocol ip parent 1:0 prio 6 handle 6 fw classid 1:15 #Se dan las reglas iptables para marcar lo que nos interesa $IPTABLES -t mangle -A PREROUTING -p icmp -j MARK --set-mark 0x1 $IPTABLES -t mangle -A PREROUTING -p icmp -j RETURN $IPTABLES -t mangle -A PREROUTING -m tos --tos Minimize-Delay -j MARK --set-mark 0x1 $IPTABLES -t mangle -A PREROUTING -m tos --tos Minimize-Delay -j RETURN $IPTABLES -t mangle -A PREROUTING -m tos --tos Minimize...

...r ------------------- FC6 Box -------------------- Emule Box external ADSL : Dynamic Internal ADSL : 192.168.254.1 external FC6 : 192.168.254.3 internal FC6 : 192.168.253.1 Emule Box : 192.168.253.3 I guess that everything is ok with layer7 . Here my mangle rules . # iptables -t mangle -A PREROUTING -mlayer7 --l7proto edonkey -j MARK --set-mark 2 # iptables -t mangle -A PREROUTING -m mark --mark 2 -j LOG --log-prefix "PREROUTING MARK : " iptables -t mangle -A FORWARD -mlayer7 --l7proto edonkey -j MARK --set-mark 2 iptables -t mangle -A FORWARD -m mark --mark 2 -j LOG --log-prefix &...

https://bugzilla.netfilter.org/show_bug.cgi?id=1117 Bug ID: 1117 Summary: Table ipv4-nat prerouting dnat doesn't accept dest IP:PORT Product: nftables Version: unspecified Hardware: x86_64 OS: All Status: NEW Severity: enhancement Priority: P5 Component: nft Assignee: pablo a...

...0 pkt per second with mark "02" the next 100 pkts per second with mark "03" the logic at the NAT table to REDIRECT these packets to port 515, 516 and so on respectively. Here is what my iptables looks like # Generated by iptables-save v1.4.4 on Tue Sep 6 11:15:41 2011 *raw :PREROUTING ACCEPT [376977:223804194] :OUTPUT ACCEPT [2336:364875] COMMIT # Completed on Tue Sep 6 11:15:41 2011 # Generated by iptables-save v1.4.4 on Tue Sep 6 11:15:41 2011 *filter :INPUT ACCEPT [243453:140022777] :FORWARD ACCEPT [0:0] :OUTPUT ACCEPT [6891:2265445] -A INPUT -p udp -m udp --dport 514 -j AC...

...ng some problems when create a HTB queue. ALL packets goes to the default queue, they don’t care about any mark or ip field I use to enqueue them. : -/ That’s the deal, all packets that incoming the interface eth2 are classified and have theirs TOS field changed following some qos policy at the PREROUTING LEVEL. Next, all packets are marked following the tos field previous changed, and them enqueued and labeled following the iptables marks. I’ve checked using ethereal, and all the packets’ TOS field are been correctly changed, and the packets are been sent to the right mpls tunnel with the righ...

...NAL_IP1 --sport $UNPRIVPORTS --dport 21 -m state --state NEW -j ACCEPT # FTP mark iptables -t mangle -A FORWARD -o $EXTERNAL_INTERFACE1 -p tcp --dport 21 -j MARK --set-mark 0x21 iptables -t mangle -A OUTPUT -o $EXTERNAL_INTERFACE1 -p tcp --dport 21 -j MARK --set-mark 0x21 iptables -t mangle -A PREROUTING -i $INTERNAL_INTERFACE -p tcp --dport 21 -j MARK --set-mark 0x21 iptables -t mangle -A FORWARD -o $EXTERNAL_INTERFACE1 -p tcp --dport 20 -j MARK --set-mark 0x21 iptables -t mangle -A OUTPUT -o $EXTERNAL_INTERFACE1 -p tcp --dport 20 -j MARK --set-mark 0x21 iptables -t mangle -A PREROUTING -i $IN...