[lwIP] Add NAT readme

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Bernard Xiong 2015-01-29 13:47:57 +00:00
parent 627d025cda
commit 7e11b8eb62
1 changed files with 19 additions and 0 deletions

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lwIP NAT componenent
If you want to use lwIP NAT componenent, please define LWIP_USING_NAT in rtconfig.h.
In this case the network 213.129.231.168/29 is nat'ed when packets are sent to the
destination network 10.0.0.0/24 (untypical example - most users will have the other
way around).
Use following code to add a NAT entry:
ip_nat_entry_t nat_entry;
nat_entry.out_if = (struct netif *)&emac_if1;
nat_entry.in_if = (struct netif *)&emac_if2;
IP4_ADDR(&nat_entry.source_net, 213, 129, 231, 168);
IP4_ADDR(&nat_entry.source_netmask, 255, 255, 255, 248);
IP4_ADDR(&nat_entry.dest_net, 10, 0, 0, 0);
IP4_ADDR(&nat_entry.source_netmask, 255, 0, 0, 0);
ip_nat_add(&_nat_entry);