From cc4fc022571376412986e27e08b0765e9cb2aafb Mon Sep 17 00:00:00 2001 From: Jan Engelhardt Date: Tue, 18 Jan 2011 17:32:40 +0100 Subject: [PATCH] netfilter: xtables: connlimit revision 1 MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit This adds destination address-based selection. The old "inverse" member is overloaded (memory-wise) with a new "flags" variable, similar to how J.Park did it with xt_string rev 1. Since revision 0 userspace only sets flag 0x1, no great changes are made to explicitly test for different revisions. Signed-off-by: Jan Engelhardt --- Documentation/feature-removal-schedule.txt | 7 +++++ include/linux/netfilter/xt_connlimit.h | 12 ++++++++ net/netfilter/xt_connlimit.c | 44 ++++++++++++++++++++---------- 3 files changed, 49 insertions(+), 14 deletions(-) diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt index 22f1081..45cc804 100644 --- a/Documentation/feature-removal-schedule.txt +++ b/Documentation/feature-removal-schedule.txt @@ -576,3 +576,10 @@ Why: The functions have been superceded by cancel_delayed_work_sync() Who: Tejun Heo ---------------------------- + +What: xt_connlimit rev 0 +When: 2012 +Who: Jan Engelhardt +Files: net/netfilter/xt_connlimit.c + +---------------------------- diff --git a/include/linux/netfilter/xt_connlimit.h b/include/linux/netfilter/xt_connlimit.h index 7e3284b..8884efc 100644 --- a/include/linux/netfilter/xt_connlimit.h +++ b/include/linux/netfilter/xt_connlimit.h @@ -3,6 +3,11 @@ struct xt_connlimit_data; +enum { + XT_CONNLIMIT_INVERT = 1 << 0, + XT_CONNLIMIT_DADDR = 1 << 1, +}; + struct xt_connlimit_info { union { union nf_inet_addr mask; @@ -14,6 +19,13 @@ struct xt_connlimit_info { #endif }; unsigned int limit, inverse; + union { + /* revision 0 */ + unsigned int inverse; + + /* revision 1 */ + __u32 flags; + }; /* Used internally by the kernel */ struct xt_connlimit_data *data __attribute__((aligned(8))); diff --git a/net/netfilter/xt_connlimit.c b/net/netfilter/xt_connlimit.c index 452bc16..7fd3fd5 100644 --- a/net/netfilter/xt_connlimit.c +++ b/net/netfilter/xt_connlimit.c @@ -193,10 +193,12 @@ connlimit_mt(const struct sk_buff *skb, struct xt_action_param *par) if (par->family == NFPROTO_IPV6) { const struct ipv6hdr *iph = ipv6_hdr(skb); - memcpy(&addr.ip6, &iph->saddr, sizeof(iph->saddr)); + memcpy(&addr.ip6, (info->flags & XT_CONNLIMIT_DADDR) ? + &iph->daddr : &iph->saddr, sizeof(addr.ip6)); } else { const struct iphdr *iph = ip_hdr(skb); - addr.ip = iph->saddr; + addr.ip = (info->flags & XT_CONNLIMIT_DADDR) ? + iph->daddr : iph->saddr; } spin_lock_bh(&info->data->lock); @@ -208,7 +210,8 @@ connlimit_mt(const struct sk_buff *skb, struct xt_action_param *par) /* kmalloc failed, drop it entirely */ goto hotdrop; - return (connections > info->limit) ^ info->inverse; + return (connections > info->limit) ^ + !!(info->flags & XT_CONNLIMIT_INVERT); hotdrop: par->hotdrop = true; @@ -266,25 +269,38 @@ static void connlimit_mt_destroy(const struct xt_mtdtor_param *par) kfree(info->data); } -static struct xt_match connlimit_mt_reg __read_mostly = { - .name = "connlimit", - .revision = 0, - .family = NFPROTO_UNSPEC, - .checkentry = connlimit_mt_check, - .match = connlimit_mt, - .matchsize = sizeof(struct xt_connlimit_info), - .destroy = connlimit_mt_destroy, - .me = THIS_MODULE, +static struct xt_match connlimit_mt_reg[] __read_mostly = { + { + .name = "connlimit", + .revision = 0, + .family = NFPROTO_UNSPEC, + .checkentry = connlimit_mt_check, + .match = connlimit_mt, + .matchsize = sizeof(struct xt_connlimit_info), + .destroy = connlimit_mt_destroy, + .me = THIS_MODULE, + }, + { + .name = "connlimit", + .revision = 1, + .family = NFPROTO_UNSPEC, + .checkentry = connlimit_mt_check, + .match = connlimit_mt, + .matchsize = sizeof(struct xt_connlimit_info), + .destroy = connlimit_mt_destroy, + .me = THIS_MODULE, + }, }; static int __init connlimit_mt_init(void) { - return xt_register_match(&connlimit_mt_reg); + return xt_register_matches(connlimit_mt_reg, + ARRAY_SIZE(connlimit_mt_reg)); } static void __exit connlimit_mt_exit(void) { - xt_unregister_match(&connlimit_mt_reg); + xt_unregister_matches(connlimit_mt_reg, ARRAY_SIZE(connlimit_mt_reg)); } module_init(connlimit_mt_init); -- 2.7.4