From f111f780ae1abf4cdc464f24293be90c010a04f6 Mon Sep 17 00:00:00 2001 From: Alexey Perevalov Date: Wed, 20 Aug 2014 22:03:18 +0400 Subject: [PATCH] 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 Signed-off-by: Pablo Neira Ayuso --- include/uapi/linux/netfilter/nfnetlink_acct.h | 8 +++ net/netfilter/nfnetlink_acct.c | 54 +++++++++++++++++++ 2 files changed, 62 insertions(+) diff --git a/include/uapi/linux/netfilter/nfnetlink_acct.h b/include/uapi/linux/netfilter/nfnetlink_acct.h index 51404ec19022..f3e34dbbf966 100644 --- a/include/uapi/linux/netfilter/nfnetlink_acct.h +++ b/include/uapi/linux/netfilter/nfnetlink_acct.h @@ -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_ */ diff --git a/net/netfilter/nfnetlink_acct.c b/net/netfilter/nfnetlink_acct.c index 3ea0eacbd970..c18af2f63eef 100644 --- a/net/netfilter/nfnetlink_acct.c +++ b/net/netfilter/nfnetlink_acct.c @@ -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] = { -- 2.20.1