diff options
| author | Romain Bellan <romain.bellan@wifirst.fr> | 2020-05-04 21:34:29 +0200 |
|---|---|---|
| committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2020-05-27 22:20:34 +0200 |
| commit | cb8aa9a3affb7d23b11b11fbed41e2feaabc4b0a (patch) | |
| tree | bf1fda7212f77fbdc824a0a627af4b0ffff066d7 /net/netfilter/nf_internals.h | |
| parent | 626a83238e6a63d88a5b5291febe797b244b5f18 (diff) | |
netfilter: ctnetlink: add kernel side filtering for dump
Conntrack dump does not support kernel side filtering (only get exists,
but it returns only one entry. And user has to give a full valid tuple)
It means that userspace has to implement filtering after receiving many
irrelevant entries, consuming resources (conntrack table is sometimes
very huge, much more than a routing table for example).
This patch adds filtering in kernel side. To achieve this goal, we:
* Add a new CTA_FILTER netlink attributes, actually a flag list to
parametize filtering
* Convert some *nlattr_to_tuple() functions, to allow a partial parsing
of CTA_TUPLE_ORIG and CTA_TUPLE_REPLY (so nf_conntrack_tuple it not
fully set)
Filtering is now possible on:
* IP SRC/DST values
* Ports for TCP and UDP flows
* IMCP(v6) codes types and IDs
Filtering is done as an "AND" operator. For example, when flags
PROTO_SRC_PORT, PROTO_NUM and IP_SRC are sets, only entries matching all
values are dumped.
Changes since v1:
Set NLM_F_DUMP_FILTERED in nlm flags if entries are filtered
Changes since v2:
Move several constants to nf_internals.h
Move a fix on netlink values check in a separate patch
Add a check on not-supported flags
Return EOPNOTSUPP if CDA_FILTER is set in ctnetlink_flush_conntrack
(not yet implemented)
Code style issues
Changes since v3:
Fix compilation warning reported by kbuild test robot
Changes since v4:
Fix a regression introduced in v3 (returned EINVAL for valid netlink
messages without CTA_MARK)
Changes since v5:
Change definition of CTA_FILTER_F_ALL
Fix a regression when CTA_TUPLE_ZONE is not set
Signed-off-by: Romain Bellan <romain.bellan@wifirst.fr>
Signed-off-by: Florent Fourcot <florent.fourcot@wifirst.fr>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'net/netfilter/nf_internals.h')
| -rw-r--r-- | net/netfilter/nf_internals.h | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/net/netfilter/nf_internals.h b/net/netfilter/nf_internals.h index d6c43902ebd7..832ae64179f0 100644 --- a/net/netfilter/nf_internals.h +++ b/net/netfilter/nf_internals.h @@ -6,6 +6,23 @@ #include <linux/skbuff.h> #include <linux/netdevice.h> +/* nf_conntrack_netlink.c: applied on tuple filters */ +#define CTA_FILTER_F_CTA_IP_SRC (1 << 0) +#define CTA_FILTER_F_CTA_IP_DST (1 << 1) +#define CTA_FILTER_F_CTA_TUPLE_ZONE (1 << 2) +#define CTA_FILTER_F_CTA_PROTO_NUM (1 << 3) +#define CTA_FILTER_F_CTA_PROTO_SRC_PORT (1 << 4) +#define CTA_FILTER_F_CTA_PROTO_DST_PORT (1 << 5) +#define CTA_FILTER_F_CTA_PROTO_ICMP_TYPE (1 << 6) +#define CTA_FILTER_F_CTA_PROTO_ICMP_CODE (1 << 7) +#define CTA_FILTER_F_CTA_PROTO_ICMP_ID (1 << 8) +#define CTA_FILTER_F_CTA_PROTO_ICMPV6_TYPE (1 << 9) +#define CTA_FILTER_F_CTA_PROTO_ICMPV6_CODE (1 << 10) +#define CTA_FILTER_F_CTA_PROTO_ICMPV6_ID (1 << 11) +#define CTA_FILTER_F_MAX (1 << 12) +#define CTA_FILTER_F_ALL (CTA_FILTER_F_MAX-1) +#define CTA_FILTER_FLAG(ctattr) CTA_FILTER_F_ ## ctattr + /* nf_queue.c */ void nf_queue_nf_hook_drop(struct net *net); |