netfilter: nfnetlink_acct: add filter support to nfacct counter list/reset

You can use this to skip accounting objects when listing/resetting
via NFNL_MSG_ACCT_GET/NFNL_MSG_ACCT_GET_CTRZERO messages with the
NLM_F_DUMP netlink flag. The filtering covers the following cases:

1. No filter specified. In this case, the client will get old behaviour,
2. List/reset counter object only: In this case, you have to use
   NFACCT_F_QUOTA as mask and value 0.
3. List/reset quota objects only: You have to use NFACCT_F_QUOTA_PKTS
   as mask and value - the same, for byte based quota mask should be
   NFACCT_F_QUOTA_BYTES and value - the same.

If you want to obtain the object with any quota type
(ie. NFACCT_F_QUOTA_PKTS|NFACCT_F_QUOTA_BYTES), you need to perform
two dump requests, one to obtain NFACCT_F_QUOTA_PKTS objects and
another for NFACCT_F_QUOTA_BYTES.

Signed-off-by: Alexey Perevalov <a.perevalov@samsung.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit is contained in:
Alexey Perevalov 2014-08-20 22:03:18 +04:00 committed by Pablo Neira Ayuso
parent 1b05756c48
commit f111f780ae
2 changed files with 62 additions and 0 deletions

View File

@ -28,9 +28,17 @@ enum nfnl_acct_type {
NFACCT_USE,
NFACCT_FLAGS,
NFACCT_QUOTA,
NFACCT_FILTER,
__NFACCT_MAX
};
#define NFACCT_MAX (__NFACCT_MAX - 1)
enum nfnl_attr_filter_type {
NFACCT_FILTER_UNSPEC,
NFACCT_FILTER_MASK,
NFACCT_FILTER_VALUE,
__NFACCT_FILTER_MAX
};
#define NFACCT_FILTER_MAX (__NFACCT_FILTER_MAX - 1)
#endif /* _UAPI_NFNL_ACCT_H_ */

View File

@ -40,6 +40,11 @@ struct nf_acct {
char data[0];
};
struct nfacct_filter {
u32 value;
u32 mask;
};
#define NFACCT_F_QUOTA (NFACCT_F_QUOTA_PKTS | NFACCT_F_QUOTA_BYTES)
#define NFACCT_OVERQUOTA_BIT 2 /* NFACCT_F_OVERQUOTA */
@ -181,6 +186,7 @@ static int
nfnl_acct_dump(struct sk_buff *skb, struct netlink_callback *cb)
{
struct nf_acct *cur, *last;
const struct nfacct_filter *filter = cb->data;
if (cb->args[2])
return 0;
@ -197,6 +203,10 @@ nfnl_acct_dump(struct sk_buff *skb, struct netlink_callback *cb)
last = NULL;
}
if (filter && (cur->flags & filter->mask) != filter->value)
continue;
if (nfnl_acct_fill_info(skb, NETLINK_CB(cb->skb).portid,
cb->nlh->nlmsg_seq,
NFNL_MSG_TYPE(cb->nlh->nlmsg_type),
@ -211,6 +221,38 @@ nfnl_acct_dump(struct sk_buff *skb, struct netlink_callback *cb)
return skb->len;
}
static int nfnl_acct_done(struct netlink_callback *cb)
{
kfree(cb->data);
return 0;
}
static const struct nla_policy filter_policy[NFACCT_FILTER_MAX + 1] = {
[NFACCT_FILTER_MASK] = { .type = NLA_U32 },
[NFACCT_FILTER_VALUE] = { .type = NLA_U32 },
};
static struct nfacct_filter *
nfacct_filter_alloc(const struct nlattr * const attr)
{
struct nfacct_filter *filter;
struct nlattr *tb[NFACCT_FILTER_MAX + 1];
int err;
err = nla_parse_nested(tb, NFACCT_FILTER_MAX, attr, filter_policy);
if (err < 0)
return ERR_PTR(err);
filter = kzalloc(sizeof(struct nfacct_filter), GFP_KERNEL);
if (!filter)
return ERR_PTR(-ENOMEM);
filter->mask = ntohl(nla_get_be32(tb[NFACCT_FILTER_MASK]));
filter->value = ntohl(nla_get_be32(tb[NFACCT_FILTER_VALUE]));
return filter;
}
static int
nfnl_acct_get(struct sock *nfnl, struct sk_buff *skb,
const struct nlmsghdr *nlh, const struct nlattr * const tb[])
@ -222,7 +264,18 @@ nfnl_acct_get(struct sock *nfnl, struct sk_buff *skb,
if (nlh->nlmsg_flags & NLM_F_DUMP) {
struct netlink_dump_control c = {
.dump = nfnl_acct_dump,
.done = nfnl_acct_done,
};
if (tb[NFACCT_FILTER]) {
struct nfacct_filter *filter;
filter = nfacct_filter_alloc(tb[NFACCT_FILTER]);
if (IS_ERR(filter))
return PTR_ERR(filter);
c.data = filter;
}
return netlink_dump_start(nfnl, skb, nlh, &c);
}
@ -314,6 +367,7 @@ static const struct nla_policy nfnl_acct_policy[NFACCT_MAX+1] = {
[NFACCT_PKTS] = { .type = NLA_U64 },
[NFACCT_FLAGS] = { .type = NLA_U32 },
[NFACCT_QUOTA] = { .type = NLA_U64 },
[NFACCT_FILTER] = {.type = NLA_NESTED },
};
static const struct nfnl_callback nfnl_acct_cb[NFNL_MSG_ACCT_MAX] = {