zapret/docs/nftables.txt

nftables test cheat sheet
simplified rules to test nfqws and tpws


For DNAT :

# run tpws as user "tpws". its required to avoid loops.

nft delete table inet ztest
nft create table inet ztest
nft add chain inet ztest pre "{type nat hook prerouting priority dstnat;}"
nft add rule inet ztest pre tcp dport "{80,443}" redirect to :988
nft add chain inet ztest out "{type nat hook output priority -100;}"
nft add rule inet ztest out tcp dport "{80,443}" skuid != tpws redirect to :988


For dpi desync attack :

nft delete table inet ztest
nft create table inet ztest
nft add chain inet ztest post "{type filter hook postrouting priority mangle;}"
nft add rule inet ztest post meta mark and 0x40000000 == 0 tcp dport "{80,443}" ct original packets 1-6 queue num 200 bypass
nft add rule inet ztest post meta mark and 0x40000000 == 0 udp dport 443 ct original packets 1-6 queue num 200 bypass

# auto hostlist with avoiding wrong ACK numbers in RST,ACK packets sent by russian DPI
sysctl net.netfilter.nf_conntrack_tcp_be_liberal=1 
nft add chain inet ztest pre "{type filter hook prerouting priority filter;}"
nft add rule inet ztest pre tcp sport "{80,443}" ct reply packets 1-3 queue num 200 bypass


show rules   : nft list table inet ztest
delete table : nft delete table inet ztest