Re: [PATCH 2/2] netfilter: ctnetlink: support kernel-space dump filterings
From: Jan Engelhardt <hidden>
Date: 2012-02-25 01:09:09
Also in:
netfilter-devel
On Friday 2012-02-24 23:14, pablo@netfilter.org wrote:
quoted hunk ↗ jump to hunk
@@ -977,9 +992,25 @@ ctnetlink_get_conntrack(struct sock *ctnl, struct sk_buff *skb,u16 zone; int err; - if (nlh->nlmsg_flags & NLM_F_DUMP) + if (nlh->nlmsg_flags & NLM_F_DUMP) { + struct ctnetlink_dump_filter *filter = NULL; + +#if defined(CONFIG_NF_CONNTRACK_MARK) + filter = kzalloc(sizeof(struct ctnetlink_dump_filter), + GFP_KERNEL); + if (filter == NULL) + return -ENOMEM; + + if (cda[CTA_MARK]) + filter->mark.value = ntohl(nla_get_be32(cda[CTA_MARK])); + if (cda[CTA_MARK_MASK]) { + filter->mark.mask = + ntohl(nla_get_be32(cda[CTA_MARK_MASK])); + } +#endif return netlink_dump_start(ctnl, skb, nlh, ctnetlink_dump_table, - ctnetlink_done, NULL, 0); + ctnetlink_done, filter, 0); + }
I had thought of the following before your patch came up:
ctnl_dump_any(skb,cb)
{
...loop over CTs...
}
ctnl_dump_foo(skb,cb)
{
if (cb->args[0] == NULL) {
cb->args[0] = filter = kzalloc(sizeof(struct ctnl_dump_filter));
if (cb->nlh has CTA_MARK) /* [1] */
filter->mark.value = ...
}
return ctnl_dump_any(skb,cb);
}
ctnl_dump_bar(skb,cb)
{
if (cb->args[0] == NULL) {
cb->args[0] = somethingelse;
}
return ctnl_dump_any(skb,cb);
}
ctnetlink_get_foo(ctnl,skb,...)
{
netlink_dump_start(ctnl,skb,nlh,ctnl_dump_foo,ctnl_done,0);
}
ctnetlink_get_bar(ctnl,skb,...)
{
netlink_dump_start(ctnl,skb,nlh,ctnl_dump_bar,ctnl_done,0);
}
[1]: Arguably needs a way to put cda into cb.
==
Either way, netlink is gathering up a lot of arguments and has come
to the point where I would suggest to put it all into a struct,
like we have done for struct xt_action_param.