diff options
Diffstat (limited to 'net/ipv4/netfilter/ipt_mac.c')
-rw-r--r-- | net/ipv4/netfilter/ipt_mac.c | 79 |
1 files changed, 79 insertions, 0 deletions
diff --git a/net/ipv4/netfilter/ipt_mac.c b/net/ipv4/netfilter/ipt_mac.c new file mode 100644 index 000000000000..11a459e33f25 --- /dev/null +++ b/net/ipv4/netfilter/ipt_mac.c @@ -0,0 +1,79 @@ +/* Kernel module to match MAC address parameters. */ + +/* (C) 1999-2001 Paul `Rusty' Russell + * (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org> + * + * 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 <linux/if_ether.h> + +#include <linux/netfilter_ipv4/ipt_mac.h> +#include <linux/netfilter_ipv4/ip_tables.h> + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>"); +MODULE_DESCRIPTION("iptables mac matching module"); + +static int +match(const struct sk_buff *skb, + const struct net_device *in, + const struct net_device *out, + const void *matchinfo, + int offset, + int *hotdrop) +{ + const struct ipt_mac_info *info = matchinfo; + + /* Is mac pointer valid? */ + return (skb->mac.raw >= skb->head + && (skb->mac.raw + ETH_HLEN) <= skb->data + /* If so, compare... */ + && ((memcmp(eth_hdr(skb)->h_source, info->srcaddr, ETH_ALEN) + == 0) ^ info->invert)); +} + +static int +ipt_mac_checkentry(const char *tablename, + const struct ipt_ip *ip, + void *matchinfo, + unsigned int matchsize, + unsigned int hook_mask) +{ + /* FORWARD isn't always valid, but it's nice to be able to do --RR */ + if (hook_mask + & ~((1 << NF_IP_PRE_ROUTING) | (1 << NF_IP_LOCAL_IN) + | (1 << NF_IP_FORWARD))) { + printk("ipt_mac: only valid for PRE_ROUTING, LOCAL_IN or FORWARD.\n"); + return 0; + } + + if (matchsize != IPT_ALIGN(sizeof(struct ipt_mac_info))) + return 0; + + return 1; +} + +static struct ipt_match mac_match = { + .name = "mac", + .match = &match, + .checkentry = &ipt_mac_checkentry, + .me = THIS_MODULE, +}; + +static int __init init(void) +{ + return ipt_register_match(&mac_match); +} + +static void __exit fini(void) +{ + ipt_unregister_match(&mac_match); +} + +module_init(init); +module_exit(fini); |