diff options
Diffstat (limited to 'net/netfilter/xt_DSCP.c')
-rw-r--r-- | net/netfilter/xt_DSCP.c | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/net/netfilter/xt_DSCP.c b/net/netfilter/xt_DSCP.c new file mode 100644 index 00000000000..a7cc75aeb38 --- /dev/null +++ b/net/netfilter/xt_DSCP.c @@ -0,0 +1,118 @@ +/* x_tables module for setting the IPv4/IPv6 DSCP field, Version 1.8 + * + * (C) 2002 by Harald Welte <laforge@netfilter.org> + * based on ipt_FTOS.c (C) 2000 by Matthew G. Marsh <mgm@paktronix.com> + * + * 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. + * + * See RFC2474 for a description of the DSCP field within the IP Header. + * + * xt_DSCP.c,v 1.8 2002/08/06 18:41:57 laforge Exp +*/ + +#include <linux/module.h> +#include <linux/skbuff.h> +#include <linux/ip.h> +#include <linux/ipv6.h> +#include <net/dsfield.h> + +#include <linux/netfilter/x_tables.h> +#include <linux/netfilter/xt_DSCP.h> + +MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>"); +MODULE_DESCRIPTION("x_tables DSCP modification module"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("ipt_DSCP"); +MODULE_ALIAS("ip6t_DSCP"); + +static unsigned int target(struct sk_buff **pskb, + const struct net_device *in, + const struct net_device *out, + unsigned int hooknum, + const struct xt_target *target, + const void *targinfo) +{ + const struct xt_DSCP_info *dinfo = targinfo; + u_int8_t dscp = ipv4_get_dsfield((*pskb)->nh.iph) >> XT_DSCP_SHIFT; + + if (dscp != dinfo->dscp) { + if (!skb_make_writable(pskb, sizeof(struct iphdr))) + return NF_DROP; + + ipv4_change_dsfield((*pskb)->nh.iph, (__u8)(~XT_DSCP_MASK), + dinfo->dscp << XT_DSCP_SHIFT); + + } + return XT_CONTINUE; +} + +static unsigned int target6(struct sk_buff **pskb, + const struct net_device *in, + const struct net_device *out, + unsigned int hooknum, + const struct xt_target *target, + const void *targinfo) +{ + const struct xt_DSCP_info *dinfo = targinfo; + u_int8_t dscp = ipv6_get_dsfield((*pskb)->nh.ipv6h) >> XT_DSCP_SHIFT; + + if (dscp != dinfo->dscp) { + if (!skb_make_writable(pskb, sizeof(struct ipv6hdr))) + return NF_DROP; + + ipv6_change_dsfield((*pskb)->nh.ipv6h, (__u8)(~XT_DSCP_MASK), + dinfo->dscp << XT_DSCP_SHIFT); + } + return XT_CONTINUE; +} + +static int checkentry(const char *tablename, + const void *e_void, + const struct xt_target *target, + void *targinfo, + unsigned int hook_mask) +{ + const u_int8_t dscp = ((struct xt_DSCP_info *)targinfo)->dscp; + + if ((dscp > XT_DSCP_MAX)) { + printk(KERN_WARNING "DSCP: dscp %x out of range\n", dscp); + return 0; + } + return 1; +} + +static struct xt_target xt_dscp_target[] = { + { + .name = "DSCP", + .family = AF_INET, + .checkentry = checkentry, + .target = target, + .targetsize = sizeof(struct xt_DSCP_info), + .table = "mangle", + .me = THIS_MODULE, + }, + { + .name = "DSCP", + .family = AF_INET6, + .checkentry = checkentry, + .target = target6, + .targetsize = sizeof(struct xt_DSCP_info), + .table = "mangle", + .me = THIS_MODULE, + }, +}; + +static int __init xt_dscp_target_init(void) +{ + return xt_register_targets(xt_dscp_target, ARRAY_SIZE(xt_dscp_target)); +} + +static void __exit xt_dscp_target_fini(void) +{ + xt_unregister_targets(xt_dscp_target, ARRAY_SIZE(xt_dscp_target)); +} + +module_init(xt_dscp_target_init); +module_exit(xt_dscp_target_fini); |