1 files changed, 79 insertions, 0 deletions
diff --git a/net/bridge/netfilter/ebt_802_3.c b/net/bridge/netfilter/ebt_802_3.c
new file mode 100644
index 000000000..68c2519bd
--- /dev/null
+++ b/net/bridge/netfilter/ebt_802_3.c
@@ -0,0 +1,79 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * 802_3
+ *
+ * Author:
+ * Chris Vitale csv@bluetail.com
+ *
+ * May 2003
+ *
+ */
+#include <linux/module.h>
+#include <linux/netfilter/x_tables.h>
+#include <linux/netfilter_bridge/ebtables.h>
+#include <linux/skbuff.h>
+#include <uapi/linux/netfilter_bridge/ebt_802_3.h>
+
+static struct ebt_802_3_hdr *ebt_802_3_hdr(const struct sk_buff *skb)
+{
+	return (struct ebt_802_3_hdr *)skb_mac_header(skb);
+}
+
+static bool
+ebt_802_3_mt(const struct sk_buff *skb, struct xt_action_param *par)
+{
+	const struct ebt_802_3_info *info = par->matchinfo;
+	const struct ebt_802_3_hdr *hdr = ebt_802_3_hdr(skb);
+	__be16 type = hdr->llc.ui.ctrl & IS_UI ? hdr->llc.ui.type : hdr->llc.ni.type;
+
+	if (info->bitmask & EBT_802_3_SAP) {
+		if (NF_INVF(info, EBT_802_3_SAP, info->sap != hdr->llc.ui.ssap))
+			return false;
+		if (NF_INVF(info, EBT_802_3_SAP, info->sap != hdr->llc.ui.dsap))
+			return false;
+	}
+
+	if (info->bitmask & EBT_802_3_TYPE) {
+		if (!(hdr->llc.ui.dsap == CHECK_TYPE && hdr->llc.ui.ssap == CHECK_TYPE))
+			return false;
+		if (NF_INVF(info, EBT_802_3_TYPE, info->type != type))
+			return false;
+	}
+
+	return true;
+}
+
+static int ebt_802_3_mt_check(const struct xt_mtchk_param *par)
+{
+	const struct ebt_802_3_info *info = par->matchinfo;
+
+	if (info->bitmask & ~EBT_802_3_MASK || info->invflags & ~EBT_802_3_MASK)
+		return -EINVAL;
+
+	return 0;
+}
+
+static struct xt_match ebt_802_3_mt_reg __read_mostly = {
+	.name		= "802_3",
+	.revision	= 0,
+	.family		= NFPROTO_BRIDGE,
+	.match		= ebt_802_3_mt,
+	.checkentry	= ebt_802_3_mt_check,
+	.matchsize	= sizeof(struct ebt_802_3_info),
+	.me		= THIS_MODULE,
+};
+
+static int __init ebt_802_3_init(void)
+{
+	return xt_register_match(&ebt_802_3_mt_reg);
+}
+
+static void __exit ebt_802_3_fini(void)
+{
+	xt_unregister_match(&ebt_802_3_mt_reg);
+}
+
+module_init(ebt_802_3_init);
+module_exit(ebt_802_3_fini);
+MODULE_DESCRIPTION("Ebtables: DSAP/SSAP field and SNAP type matching");
+MODULE_LICENSE("GPL");