diff options
Diffstat (limited to 'net/ipv4/netfilter/ipt_dccp.c')
-rw-r--r-- | net/ipv4/netfilter/ipt_dccp.c | 176 |
1 files changed, 0 insertions, 176 deletions
diff --git a/net/ipv4/netfilter/ipt_dccp.c b/net/ipv4/netfilter/ipt_dccp.c deleted file mode 100644 index ad3278b..0000000 --- a/net/ipv4/netfilter/ipt_dccp.c +++ /dev/null @@ -1,176 +0,0 @@ -/* - * iptables module for DCCP protocol header matching - * - * (C) 2005 by Harald Welte <laforge@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/spinlock.h> -#include <net/ip.h> -#include <linux/dccp.h> - -#include <linux/netfilter_ipv4/ip_tables.h> -#include <linux/netfilter_ipv4/ipt_dccp.h> - -#define DCCHECK(cond, option, flag, invflag) (!((flag) & (option)) \ - || (!!((invflag) & (option)) ^ (cond))) - -static unsigned char *dccp_optbuf; -static DEFINE_SPINLOCK(dccp_buflock); - -static inline int -dccp_find_option(u_int8_t option, - const struct sk_buff *skb, - const struct dccp_hdr *dh, - int *hotdrop) -{ - /* tcp.doff is only 4 bits, ie. max 15 * 4 bytes */ - unsigned char *op; - unsigned int optoff = __dccp_hdr_len(dh); - unsigned int optlen = dh->dccph_doff*4 - __dccp_hdr_len(dh); - unsigned int i; - - if (dh->dccph_doff * 4 < __dccp_hdr_len(dh)) { - *hotdrop = 1; - return 0; - } - - if (!optlen) - return 0; - - spin_lock_bh(&dccp_buflock); - op = skb_header_pointer(skb, - skb->nh.iph->ihl*4 + optoff, - optlen, dccp_optbuf); - if (op == NULL) { - /* If we don't have the whole header, drop packet. */ - spin_unlock_bh(&dccp_buflock); - *hotdrop = 1; - return 0; - } - - for (i = 0; i < optlen; ) { - if (op[i] == option) { - spin_unlock_bh(&dccp_buflock); - return 1; - } - - if (op[i] < 2) - i++; - else - i += op[i+1]?:1; - } - - spin_unlock_bh(&dccp_buflock); - return 0; -} - - -static inline int -match_types(const struct dccp_hdr *dh, u_int16_t typemask) -{ - return (typemask & (1 << dh->dccph_type)); -} - -static inline int -match_option(u_int8_t option, const struct sk_buff *skb, - const struct dccp_hdr *dh, int *hotdrop) -{ - return dccp_find_option(option, skb, dh, hotdrop); -} - -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_dccp_info *info = - (const struct ipt_dccp_info *)matchinfo; - struct dccp_hdr _dh, *dh; - - if (offset) - return 0; - - dh = skb_header_pointer(skb, skb->nh.iph->ihl*4, sizeof(_dh), &_dh); - if (dh == NULL) { - *hotdrop = 1; - return 0; - } - - return DCCHECK(((ntohs(dh->dccph_sport) >= info->spts[0]) - && (ntohs(dh->dccph_sport) <= info->spts[1])), - IPT_DCCP_SRC_PORTS, info->flags, info->invflags) - && DCCHECK(((ntohs(dh->dccph_dport) >= info->dpts[0]) - && (ntohs(dh->dccph_dport) <= info->dpts[1])), - IPT_DCCP_DEST_PORTS, info->flags, info->invflags) - && DCCHECK(match_types(dh, info->typemask), - IPT_DCCP_TYPE, info->flags, info->invflags) - && DCCHECK(match_option(info->option, skb, dh, hotdrop), - IPT_DCCP_OPTION, info->flags, info->invflags); -} - -static int -checkentry(const char *tablename, - const struct ipt_ip *ip, - void *matchinfo, - unsigned int matchsize, - unsigned int hook_mask) -{ - const struct ipt_dccp_info *info; - - info = (const struct ipt_dccp_info *)matchinfo; - - return ip->proto == IPPROTO_DCCP - && !(ip->invflags & IPT_INV_PROTO) - && matchsize == IPT_ALIGN(sizeof(struct ipt_dccp_info)) - && !(info->flags & ~IPT_DCCP_VALID_FLAGS) - && !(info->invflags & ~IPT_DCCP_VALID_FLAGS) - && !(info->invflags & ~info->flags); -} - -static struct ipt_match dccp_match = -{ - .name = "dccp", - .match = &match, - .checkentry = &checkentry, - .me = THIS_MODULE, -}; - -static int __init init(void) -{ - int ret; - - /* doff is 8 bits, so the maximum option size is (4*256). Don't put - * this in BSS since DaveM is worried about locked TLB's for kernel - * BSS. */ - dccp_optbuf = kmalloc(256 * 4, GFP_KERNEL); - if (!dccp_optbuf) - return -ENOMEM; - ret = ipt_register_match(&dccp_match); - if (ret) - kfree(dccp_optbuf); - - return ret; -} - -static void __exit fini(void) -{ - ipt_unregister_match(&dccp_match); - kfree(dccp_optbuf); -} - -module_init(init); -module_exit(fini); - -MODULE_LICENSE("GPL"); -MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>"); -MODULE_DESCRIPTION("Match for DCCP protocol packets"); - |