From 2e4e6a17af35be359cc8f1c924f8f198fbd478cc Mon Sep 17 00:00:00 2001 From: Harald Welte Date: Thu, 12 Jan 2006 13:30:04 -0800 Subject: [NETFILTER] x_tables: Abstraction layer for {ip,ip6,arp}_tables This monster-patch tries to do the best job for unifying the data structures and backend interfaces for the three evil clones ip_tables, ip6_tables and arp_tables. In an ideal world we would never have allowed this kind of copy+paste programming... but well, our world isn't (yet?) ideal. o introduce a new x_tables module o {ip,arp,ip6}_tables depend on this x_tables module o registration functions for tables, matches and targets are only wrappers around x_tables provided functions o all matches/targets that are used from ip_tables and ip6_tables are now implemented as xt_FOOBAR.c files and provide module aliases to ipt_FOOBAR and ip6t_FOOBAR o header files for xt_matches are in include/linux/netfilter/, include/linux/netfilter_{ipv4,ipv6} contains compatibility wrappers around the xt_FOOBAR.h headers Based on this patchset we're going to further unify the code, gradually getting rid of all the layer 3 specific assumptions. Signed-off-by: Harald Welte Signed-off-by: David S. Miller --- net/netfilter/xt_CONNMARK.c | 141 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 141 insertions(+) create mode 100644 net/netfilter/xt_CONNMARK.c (limited to 'net/netfilter/xt_CONNMARK.c') diff --git a/net/netfilter/xt_CONNMARK.c b/net/netfilter/xt_CONNMARK.c new file mode 100644 index 00000000000..22506e376be --- /dev/null +++ b/net/netfilter/xt_CONNMARK.c @@ -0,0 +1,141 @@ +/* This kernel module is used to modify the connection mark values, or + * to optionally restore the skb nfmark from the connection mark + * + * Copyright (C) 2002,2004 MARA Systems AB + * by Henrik Nordstrom + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ +#include +#include +#include +#include + +MODULE_AUTHOR("Henrik Nordstrom "); +MODULE_DESCRIPTION("IP tables CONNMARK matching module"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("ipt_CONNMARK"); + +#include +#include +#include + +static unsigned int +target(struct sk_buff **pskb, + const struct net_device *in, + const struct net_device *out, + unsigned int hooknum, + const void *targinfo, + void *userinfo) +{ + const struct xt_connmark_target_info *markinfo = targinfo; + u_int32_t diff; + u_int32_t nfmark; + u_int32_t newmark; + u_int32_t ctinfo; + u_int32_t *ctmark = nf_ct_get_mark(*pskb, &ctinfo); + + if (ctmark) { + switch(markinfo->mode) { + case XT_CONNMARK_SET: + newmark = (*ctmark & ~markinfo->mask) | markinfo->mark; + if (newmark != *ctmark) + *ctmark = newmark; + break; + case XT_CONNMARK_SAVE: + newmark = (*ctmark & ~markinfo->mask) | ((*pskb)->nfmark & markinfo->mask); + if (*ctmark != newmark) + *ctmark = newmark; + break; + case XT_CONNMARK_RESTORE: + nfmark = (*pskb)->nfmark; + diff = (*ctmark ^ nfmark) & markinfo->mask; + if (diff != 0) + (*pskb)->nfmark = nfmark ^ diff; + break; + } + } + + return XT_CONTINUE; +} + +static int +checkentry(const char *tablename, + const void *entry, + void *targinfo, + unsigned int targinfosize, + unsigned int hook_mask) +{ + struct xt_connmark_target_info *matchinfo = targinfo; + if (targinfosize != XT_ALIGN(sizeof(struct xt_connmark_target_info))) { + printk(KERN_WARNING "CONNMARK: targinfosize %u != %Zu\n", + targinfosize, + XT_ALIGN(sizeof(struct xt_connmark_target_info))); + return 0; + } + + if (matchinfo->mode == XT_CONNMARK_RESTORE) { + if (strcmp(tablename, "mangle") != 0) { + printk(KERN_WARNING "CONNMARK: restore can only be called from \"mangle\" table, not \"%s\"\n", tablename); + return 0; + } + } + + if (matchinfo->mark > 0xffffffff || matchinfo->mask > 0xffffffff) { + printk(KERN_WARNING "CONNMARK: Only supports 32bit mark\n"); + return 0; + } + + return 1; +} + +static struct xt_target connmark_reg = { + .name = "CONNMARK", + .target = &target, + .checkentry = &checkentry, + .me = THIS_MODULE +}; +static struct xt_target connmark6_reg = { + .name = "CONNMARK", + .target = &target, + .checkentry = &checkentry, + .me = THIS_MODULE +}; + +static int __init init(void) +{ + int ret; + + need_conntrack(); + + ret = xt_register_target(AF_INET, &connmark_reg); + if (ret) + return ret; + + ret = xt_register_target(AF_INET6, &connmark6_reg); + if (ret) + xt_unregister_target(AF_INET, &connmark_reg); + + return ret; +} + +static void __exit fini(void) +{ + xt_unregister_target(AF_INET, &connmark_reg); + xt_unregister_target(AF_INET6, &connmark6_reg); +} + +module_init(init); +module_exit(fini); -- cgit v1.2.3