netfilter: ctnetlink: add and use a helper for mark parsing

ctnetlink dumps can be filtered based on the connmark.

Prepare for status bit filtering by using a named structure and by
moving the mark parsing code to a helper.

Else ctnetlink_alloc_filter size grows a bit too big for my taste
when status handling is added.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit is contained in:
Florian Westphal 2021-07-30 15:14:21 +02:00 committed by Pablo Neira Ayuso
parent 87663c39f8
commit ff1199db8c

View File

@ -852,6 +852,11 @@ static int ctnetlink_done(struct netlink_callback *cb)
return 0;
}
struct ctnetlink_filter_u32 {
u32 val;
u32 mask;
};
struct ctnetlink_filter {
u8 family;
@ -862,10 +867,7 @@ struct ctnetlink_filter {
struct nf_conntrack_tuple reply;
struct nf_conntrack_zone zone;
struct {
u_int32_t val;
u_int32_t mask;
} mark;
struct ctnetlink_filter_u32 mark;
};
static const struct nla_policy cta_filter_nla_policy[CTA_FILTER_MAX + 1] = {
@ -907,6 +909,24 @@ static int ctnetlink_parse_tuple_filter(const struct nlattr * const cda[],
struct nf_conntrack_zone *zone,
u_int32_t flags);
static int ctnetlink_filter_parse_mark(struct ctnetlink_filter_u32 *mark,
const struct nlattr * const cda[])
{
#ifdef CONFIG_NF_CONNTRACK_MARK
if (cda[CTA_MARK]) {
mark->val = ntohl(nla_get_be32(cda[CTA_MARK]));
if (cda[CTA_MARK_MASK])
mark->mask = ntohl(nla_get_be32(cda[CTA_MARK_MASK]));
else
mark->mask = 0xffffffff;
} else if (cda[CTA_MARK_MASK]) {
return -EINVAL;
}
#endif
return 0;
}
static struct ctnetlink_filter *
ctnetlink_alloc_filter(const struct nlattr * const cda[], u8 family)
{
@ -924,18 +944,10 @@ ctnetlink_alloc_filter(const struct nlattr * const cda[], u8 family)
filter->family = family;
#ifdef CONFIG_NF_CONNTRACK_MARK
if (cda[CTA_MARK]) {
filter->mark.val = ntohl(nla_get_be32(cda[CTA_MARK]));
if (cda[CTA_MARK_MASK])
filter->mark.mask = ntohl(nla_get_be32(cda[CTA_MARK_MASK]));
else
filter->mark.mask = 0xffffffff;
} else if (cda[CTA_MARK_MASK]) {
err = -EINVAL;
err = ctnetlink_filter_parse_mark(&filter->mark, cda);
if (err)
goto err_filter;
}
#endif
if (!cda[CTA_FILTER])
return filter;