diff options
Diffstat (limited to 'net/ipv6/netfilter/ip6t_length.c')
-rw-r--r-- | net/ipv6/netfilter/ip6t_length.c | 66 |
1 files changed, 66 insertions, 0 deletions
diff --git a/net/ipv6/netfilter/ip6t_length.c b/net/ipv6/netfilter/ip6t_length.c new file mode 100644 index 00000000000..e0537d3811d --- /dev/null +++ b/net/ipv6/netfilter/ip6t_length.c @@ -0,0 +1,66 @@ +/* Length Match - IPv6 Port */ + +/* (C) 1999-2001 James Morris <jmorros@intercode.com.au> + * + * 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/netfilter_ipv6/ip6t_length.h> +#include <linux/netfilter_ipv6/ip6_tables.h> + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("James Morris <jmorris@intercode.com.au>"); +MODULE_DESCRIPTION("IPv6 packet length match"); + +static int +match(const struct sk_buff *skb, + const struct net_device *in, + const struct net_device *out, + const void *matchinfo, + int offset, + unsigned int protoff, + int *hotdrop) +{ + const struct ip6t_length_info *info = matchinfo; + u_int16_t pktlen = ntohs(skb->nh.ipv6h->payload_len) + sizeof(struct ipv6hdr); + + return (pktlen >= info->min && pktlen <= info->max) ^ info->invert; +} + +static int +checkentry(const char *tablename, + const struct ip6t_ip6 *ip, + void *matchinfo, + unsigned int matchsize, + unsigned int hook_mask) +{ + if (matchsize != IP6T_ALIGN(sizeof(struct ip6t_length_info))) + return 0; + + return 1; +} + +static struct ip6t_match length_match = { + .name = "length", + .match = &match, + .checkentry = &checkentry, + .me = THIS_MODULE, +}; + +static int __init init(void) +{ + return ip6t_register_match(&length_match); +} + +static void __exit fini(void) +{ + ip6t_unregister_match(&length_match); +} + +module_init(init); +module_exit(fini); |