aboutsummaryrefslogtreecommitdiffstats
path: root/net/netfilter/xt_connlabel.c
diff options
context:
space:
mode:
Diffstat (limited to 'net/netfilter/xt_connlabel.c')
-rw-r--r--net/netfilter/xt_connlabel.c99
1 files changed, 99 insertions, 0 deletions
diff --git a/net/netfilter/xt_connlabel.c b/net/netfilter/xt_connlabel.c
new file mode 100644
index 000000000000..9f8719df2001
--- /dev/null
+++ b/net/netfilter/xt_connlabel.c
@@ -0,0 +1,99 @@
+/*
+ * (C) 2013 Astaro GmbH & Co KG
+ *
+ * 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 <linux/module.h>
+#include <linux/skbuff.h>
+#include <net/netfilter/nf_conntrack.h>
+#include <net/netfilter/nf_conntrack_labels.h>
+#include <linux/netfilter/x_tables.h>
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Florian Westphal <fw@strlen.de>");
+MODULE_DESCRIPTION("Xtables: add/match connection trackling labels");
+MODULE_ALIAS("ipt_connlabel");
+MODULE_ALIAS("ip6t_connlabel");
+
+static bool
+connlabel_mt(const struct sk_buff *skb, struct xt_action_param *par)
+{
+ const struct xt_connlabel_mtinfo *info = par->matchinfo;
+ enum ip_conntrack_info ctinfo;
+ struct nf_conn *ct;
+ bool invert = info->options & XT_CONNLABEL_OP_INVERT;
+
+ ct = nf_ct_get(skb, &ctinfo);
+ if (ct == NULL || nf_ct_is_untracked(ct))
+ return invert;
+
+ if (info->options & XT_CONNLABEL_OP_SET)
+ return (nf_connlabel_set(ct, info->bit) == 0) ^ invert;
+
+ return nf_connlabel_match(ct, info->bit) ^ invert;
+}
+
+static int connlabel_mt_check(const struct xt_mtchk_param *par)
+{
+ const int options = XT_CONNLABEL_OP_INVERT |
+ XT_CONNLABEL_OP_SET;
+ struct xt_connlabel_mtinfo *info = par->matchinfo;
+ int ret;
+ size_t words;
+
+ if (info->bit > XT_CONNLABEL_MAXBIT)
+ return -ERANGE;
+
+ if (info->options & ~options) {
+ pr_err("Unknown options in mask %x\n", info->options);
+ return -EINVAL;
+ }
+
+ ret = nf_ct_l3proto_try_module_get(par->family);
+ if (ret < 0) {
+ pr_info("cannot load conntrack support for proto=%u\n",
+ par->family);
+ return ret;
+ }
+
+ par->net->ct.labels_used++;
+ words = BITS_TO_LONGS(info->bit+1);
+ if (words > par->net->ct.label_words)
+ par->net->ct.label_words = words;
+
+ return ret;
+}
+
+static void connlabel_mt_destroy(const struct xt_mtdtor_param *par)
+{
+ par->net->ct.labels_used--;
+ if (par->net->ct.labels_used == 0)
+ par->net->ct.label_words = 0;
+ nf_ct_l3proto_module_put(par->family);
+}
+
+static struct xt_match connlabels_mt_reg __read_mostly = {
+ .name = "connlabel",
+ .family = NFPROTO_UNSPEC,
+ .checkentry = connlabel_mt_check,
+ .match = connlabel_mt,
+ .matchsize = sizeof(struct xt_connlabel_mtinfo),
+ .destroy = connlabel_mt_destroy,
+ .me = THIS_MODULE,
+};
+
+static int __init connlabel_mt_init(void)
+{
+ return xt_register_match(&connlabels_mt_reg);
+}
+
+static void __exit connlabel_mt_exit(void)
+{
+ xt_unregister_match(&connlabels_mt_reg);
+}
+
+module_init(connlabel_mt_init);
+module_exit(connlabel_mt_exit);