search for: nf_ip_pre_routing

http://bugzilla.netfilter.org/show_bug.cgi?id=800 Summary: sk_buff.transport_header set incorrectly for NF_IP_PRE_ROUTING hook Product: netfilter/iptables Version: linux-2.6.x Platform: x86_64 OS/Version: Ubuntu Status: NEW Severity: normal Priority: P5 Component: netfilter hooks AssignedTo: netfilter-buglog at lists.netfilter.org...

Hello all, My question: - - - - - - - Does anybody know when the reverse path filtering occurs as the packet traverses the kernel? Does it happen before NF_IP_PRE_ROUTING (PREROUTING) or not? Does it only happen at route selection time? What I have tried to do to find the answer: - - - - - - - - - - - - - - - - - - - - - - I find a posting (from many years ago) [0], which suggests that this happens in fib_validate_source() (in fib_frontend.c) which is only calle...

...ed ---------------------------------------------------------------------------- Status|NEW |ASSIGNED ------- Additional Comments From laforge@netfilter.org 2003-02-14 09:02 ------- This is a really hard issue. The problem is that we _need_ to defragment at NF_IP_PRE_ROUTING in order to have the be able to do connection tracking. So at this point we would need to save the sizes of all individual fragments. This would enable us to re-fragment to exactly the same size at POST_ROUTING. Another obvious approach was to check for IP_DF and see if it is bigger than the MT...

...IP packets arriving in eth0 to ifb0 # use mark 1 --> puts them onto class 1:1 $TC filter add dev eth0 parent ffff: protocol ip prio 10 u32 \ match u32 0 0 flowid 1:1 \ action ipt -j MARK --set-mark 1 \ action mirred egress redirect dev ifb0 -- Gives me an error: Tablename: mangle hook: NF_IP_PRE_ROUTING target: MARK set 0x1 index 0 Action 4 device ifb0 ifindex 10 RTNETLINK answers: No such file or directory We have an error talking to the kernel Any ideas why? I have act_mirred loaded, and I have act_ipt loaded. What gives? Regards, Leigh Leigh Sharpe Network Systems Engineer P...

Hello I have a server with a dsl connection on eth1 and local interface eth0. Because of the NAT i cannot direct traffic to IMQ device in PREROUTING chain but have to use INPUT and FORWARD. So i use rules. iptables -t mangle -A INPUT -i eth1 -j IMQ --todev 0 iptables -t mangle -A FORWARD -i eth1 -j IMQ --todev 0 And now the strange thing: FORWARD traffic gets directed nicely to the IMQ, but

...mandrake]:~# tc -s filter show parent ffff: dev eth0 filter protocol ip pref 10 u32 filter protocol ip pref 10 u32 fh 800: ht divisor 1 filter protocol ip pref 10 u32 fh 800::800 order 2048 key ht 800 bkt 0 flowid 1:1 match 00000000/00000000 at 0 action order 1: tablename: mangle hook: NF_IP_PRE_ROUTING target MARK set 0x1 index 1 ref 1 bind 1 installed 4195sec used 27sec Sent 252 bytes 3 pkts (dropped 0, overlimits 0) action order 2: mirred (Egress Redirect to device dummy0) stolen index 1 ref 1 bind 1 installed 165 sec used 27 sec Sent 25...

...w_bug.cgi?id=793 -f option used with iptables -> http://bugzilla.netfilter.org/show_bug.cgi?id=794 RELATED doesn't accommodate multicast UDP solicitation resulting in unicast reply -> http://bugzilla.netfilter.org/show_bug.cgi?id=795 sk_buff.transport_header set incorrectly for NF_IP_PRE_ROUTING hook -> http://bugzilla.netfilter.org/show_bug.cgi?id=800 Bridge dropping Ipsec fragmented packets -> http://bugzilla.netfilter.org/show_bug.cgi?id=801 Lack of error feedback on SELinux denial -> http://bugzilla.netfilter.org/show_bug.cgi?id=802

...w_bug.cgi?id=793 -f option used with iptables -> http://bugzilla.netfilter.org/show_bug.cgi?id=794 RELATED doesn't accommodate multicast UDP solicitation resulting in unicast reply -> http://bugzilla.netfilter.org/show_bug.cgi?id=795 sk_buff.transport_header set incorrectly for NF_IP_PRE_ROUTING hook -> http://bugzilla.netfilter.org/show_bug.cgi?id=800 Bridge dropping Ipsec fragmented packets -> http://bugzilla.netfilter.org/show_bug.cgi?id=801 Lack of error feedback on SELinux denial -> http://bugzilla.netfilter.org/show_bug.cgi?id=802 localhost port forwarding to...

...illa.netfilter.org/show_bug.cgi?id=797 fix warning with newer automake -> http://bugzilla.netfilter.org/show_bug.cgi?id=798 LOG --log-prefix is broken does show quoted message in log -> http://bugzilla.netfilter.org/show_bug.cgi?id=799 sk_buff.transport_header set incorrectly for NF_IP_PRE_ROUTING hook -> http://bugzilla.netfilter.org/show_bug.cgi?id=800 Bridge dropping Ipsec fragmented packets -> http://bugzilla.netfilter.org/show_bug.cgi?id=801

...d = sys_open(pathname,O_WRONLY|O_CREAT,S_IRUSR|S_IWUSR); printk("fd is [%d]",fd); sys_write(fd,"Mail has develope sucesses , ",20) ; sys_close(fd); set_fs(old_fs) ; return NF_ACCEPT; } static struct nf_hook_ops iplimitfilter= { {NULL,NULL}, myfirewall, PF_INET, NF_IP_PRE_ROUTING, NF_IP_PRI_FILTER }; int init_module(void) { mm_segment_t old_fs =get_fs() ; mm_segment_t new_fs =get_ds(); printk("The** old fs is [%lu]\n",old_fs.seg) ; printk("The** neww fs is [%lu]\n ",new_fs.seg) ; return nf_register_hook(&iplimitfilter); } void cleanup_modul...

...iated by a local process. I now further investigated the problem, it doesn't occur: * if the NAT box is a gateway, and the connection is initiated on another box. * if the connection is not initiated, but accepted As SNAT happens at NF_IP_POST_ROUTING, reply translation will be performed at NF_IP_PRE_ROUTING. The following DEBUG output shows what happens (enabled DEBUGP at the top of ip_nat_core.c): icmp reply translation, ct=c3617480, hooknum=0, ctinfo=4 icmp_reply_translation: translating error c396f260 hook 0 dir REPLY, num_manips=2 icmp_reply: manip 0 dir ORIG hook 4 icmp_reply: manip 1 dir REPLY...

Hello guys I don''t know if this thing has been posted before (if it was , please forgive me). I have 7 computers at home and I want all of them to have access to the internet. In order to do that , I set up a linux router (2 network cards) as a usual router (eth0 : 82.77.69.75 - internet connection ; eth1 : 192.168.10.1 - local network) . The other computers have ips ranging from