diff options
Diffstat (limited to 'net/bridge/netfilter/ebt_802_3.c')
-rw-r--r-- | net/bridge/netfilter/ebt_802_3.c | 72 |
1 files changed, 72 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..2a449b7ab --- /dev/null +++ b/net/bridge/netfilter/ebt_802_3.c @@ -0,0 +1,72 @@ +/* + * 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/netfilter_bridge/ebt_802_3.h> + +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 (FWINV(info->sap != hdr->llc.ui.ssap, EBT_802_3_SAP)) + return false; + if (FWINV(info->sap != hdr->llc.ui.dsap, EBT_802_3_SAP)) + 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 (FWINV(info->type != type, EBT_802_3_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"); |