netfilter: nat: merge nf_nat_ipv4,6 into nat core
before:
text data bss dec hex filename
16566 1576 4136 22278 5706 nf_nat.ko
3598 844 0 4442 115a nf_nat_ipv6.ko
3187 844 0 4031 fbf nf_nat_ipv4.ko
after:
text data bss dec hex filename
22948 1612 4136 28696 7018 nf_nat.ko
... with ipv4/v6 nat now provided directly via nf_nat.ko.
Also changes:
ret = nf_nat_ipv4_fn(priv, skb, state);
if (ret != NF_DROP && ret != NF_STOLEN &&
into
if (ret != NF_ACCEPT)
return ret;
everywhere.
The nat hooks never should return anything other than
ACCEPT or DROP (and the latter only in rare error cases).
The original code uses multi-line ANDing including assignment-in-if:
if (ret != NF_DROP && ret != NF_STOLEN &&
!(IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) &&
(ct = nf_ct_get(skb, &ctinfo)) != NULL) {
I removed this while moving, breaking those in separate conditionals
and moving the assignments into extra lines.
checkpatch still generates some warnings:
1. Overly long lines (of moved code).
Breaking them is even more ugly. so I kept this as-is.
2. use of extern function declarations in a .c file.
This is necessary evil, we must call
nf_nat_l3proto_register() from the nat core now.
All l3proto related functions are removed later in this series,
those prototypes are then removed as well.
v2: keep empty nf_nat_ipv6_csum_update stub for CONFIG_IPV6=n case.
v3: remove IS_ENABLED(NF_NAT_IPV4/6) tests, NF_NAT_IPVx toggles
are removed here.
v4: also get rid of the assignments in conditionals.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
12 files changed
