From 6d4fa852a023080101f1665ea189dd1844c87fef Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Wed, 11 Jul 2012 10:56:57 +0000 Subject: net: sched: add ipset ematch Can be used to match packets against netfilter ip sets created via ipset(8). skb->sk_iif is used as 'incoming interface', skb->dev is 'outgoing interface'. Since ipset is usually called from netfilter, the ematch initializes a fake xt_action_param, pulls the ip header into the linear area and also sets skb->data to the IP header (otherwise matching Layer 4 set types doesn't work). Tested-by: Mr Dash Four Signed-off-by: Florian Westphal Signed-off-by: David S. Miller --- net/sched/em_ipset.c | 135 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 135 insertions(+) create mode 100644 net/sched/em_ipset.c (limited to 'net/sched/em_ipset.c') diff --git a/net/sched/em_ipset.c b/net/sched/em_ipset.c new file mode 100644 index 000000000000..3130320997e2 --- /dev/null +++ b/net/sched/em_ipset.c @@ -0,0 +1,135 @@ +/* + * net/sched/em_ipset.c ipset ematch + * + * Copyright (c) 2012 Florian Westphal + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * version 2 as published by the Free Software Foundation. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +static int em_ipset_change(struct tcf_proto *tp, void *data, int data_len, + struct tcf_ematch *em) +{ + struct xt_set_info *set = data; + ip_set_id_t index; + + if (data_len != sizeof(*set)) + return -EINVAL; + + index = ip_set_nfnl_get_byindex(set->index); + if (index == IPSET_INVALID_ID) + return -ENOENT; + + em->datalen = sizeof(*set); + em->data = (unsigned long)kmemdup(data, em->datalen, GFP_KERNEL); + if (em->data) + return 0; + + ip_set_nfnl_put(index); + return -ENOMEM; +} + +static void em_ipset_destroy(struct tcf_proto *p, struct tcf_ematch *em) +{ + const struct xt_set_info *set = (const void *) em->data; + if (set) { + ip_set_nfnl_put(set->index); + kfree((void *) em->data); + } +} + +static int em_ipset_match(struct sk_buff *skb, struct tcf_ematch *em, + struct tcf_pkt_info *info) +{ + struct ip_set_adt_opt opt; + struct xt_action_param acpar; + const struct xt_set_info *set = (const void *) em->data; + struct net_device *dev, *indev = NULL; + int ret, network_offset; + + switch (skb->protocol) { + case htons(ETH_P_IP): + acpar.family = NFPROTO_IPV4; + if (!pskb_network_may_pull(skb, sizeof(struct iphdr))) + return 0; + acpar.thoff = ip_hdrlen(skb); + break; + case htons(ETH_P_IPV6): + acpar.family = NFPROTO_IPV6; + if (!pskb_network_may_pull(skb, sizeof(struct ipv6hdr))) + return 0; + /* doesn't call ipv6_find_hdr() because ipset doesn't use thoff, yet */ + acpar.thoff = sizeof(struct ipv6hdr); + break; + default: + return 0; + } + + acpar.hooknum = 0; + + opt.family = acpar.family; + opt.dim = set->dim; + opt.flags = set->flags; + opt.cmdflags = 0; + opt.timeout = ~0u; + + network_offset = skb_network_offset(skb); + skb_pull(skb, network_offset); + + dev = skb->dev; + + rcu_read_lock(); + + if (dev && skb->skb_iif) + indev = dev_get_by_index_rcu(dev_net(dev), skb->skb_iif); + + acpar.in = indev ? indev : dev; + acpar.out = dev; + + ret = ip_set_test(set->index, skb, &acpar, &opt); + + rcu_read_unlock(); + + skb_push(skb, network_offset); + return ret; +} + +static struct tcf_ematch_ops em_ipset_ops = { + .kind = TCF_EM_IPSET, + .change = em_ipset_change, + .destroy = em_ipset_destroy, + .match = em_ipset_match, + .owner = THIS_MODULE, + .link = LIST_HEAD_INIT(em_ipset_ops.link) +}; + +static int __init init_em_ipset(void) +{ + return tcf_em_register(&em_ipset_ops); +} + +static void __exit exit_em_ipset(void) +{ + tcf_em_unregister(&em_ipset_ops); +} + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Florian Westphal "); +MODULE_DESCRIPTION("TC extended match for IP sets"); + +module_init(init_em_ipset); +module_exit(exit_em_ipset); + +MODULE_ALIAS_TCF_EMATCH(TCF_EM_IPSET); -- cgit v1.2.3-58-ga151