12345678910111213141516171819202122232425262728293031323334353637383940414243444546474849505152535455565758596061626364656667686970717273747576777879 |
- // 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");
|