#include <linux/netfilter/x_tables.h>
#include <linux/netfilter/xt_DSCP.h>
+#include <linux/netfilter_ipv4/ipt_TOS.h>
MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
-MODULE_DESCRIPTION("x_tables DSCP modification module");
+MODULE_DESCRIPTION("Xtables: DSCP/TOS field modification");
MODULE_LICENSE("GPL");
MODULE_ALIAS("ipt_DSCP");
MODULE_ALIAS("ip6t_DSCP");
+MODULE_ALIAS("ipt_TOS");
+MODULE_ALIAS("ip6t_TOS");
static unsigned int
dscp_tg(struct sk_buff *skb, const struct net_device *in,
return true;
}
+static unsigned int
+tos_tg_v0(struct sk_buff *skb, const struct net_device *in,
+ const struct net_device *out, unsigned int hooknum,
+ const struct xt_target *target, const void *targinfo)
+{
+ const struct ipt_tos_target_info *info = targinfo;
+ struct iphdr *iph = ip_hdr(skb);
+ u_int8_t oldtos;
+
+ if ((iph->tos & IPTOS_TOS_MASK) != info->tos) {
+ if (!skb_make_writable(skb, sizeof(struct iphdr)))
+ return NF_DROP;
+
+ iph = ip_hdr(skb);
+ oldtos = iph->tos;
+ iph->tos = (iph->tos & IPTOS_PREC_MASK) | info->tos;
+ csum_replace2(&iph->check, htons(oldtos), htons(iph->tos));
+ }
+
+ return XT_CONTINUE;
+}
+
+static bool
+tos_tg_check_v0(const char *tablename, const void *e_void,
+ const struct xt_target *target, void *targinfo,
+ unsigned int hook_mask)
+{
+ const u_int8_t tos = ((struct ipt_tos_target_info *)targinfo)->tos;
+
+ if (tos != IPTOS_LOWDELAY && tos != IPTOS_THROUGHPUT &&
+ tos != IPTOS_RELIABILITY && tos != IPTOS_MINCOST &&
+ tos != IPTOS_NORMALSVC) {
+ printk(KERN_WARNING "TOS: bad tos value %#x\n", tos);
+ return false;
+ }
+
+ return true;
+}
+
+static unsigned int
+tos_tg(struct sk_buff *skb, const struct net_device *in,
+ const struct net_device *out, unsigned int hooknum,
+ const struct xt_target *target, const void *targinfo)
+{
+ const struct xt_tos_target_info *info = targinfo;
+ struct iphdr *iph = ip_hdr(skb);
+ u_int8_t orig, nv;
+
+ orig = ipv4_get_dsfield(iph);
+ nv = (orig & ~info->tos_mask) ^ info->tos_value;
+
+ if (orig != nv) {
+ if (!skb_make_writable(skb, sizeof(struct iphdr)))
+ return NF_DROP;
+ iph = ip_hdr(skb);
+ ipv4_change_dsfield(iph, 0, nv);
+ }
+
+ return XT_CONTINUE;
+}
+
+static unsigned int
+tos_tg6(struct sk_buff *skb, const struct net_device *in,
+ const struct net_device *out, unsigned int hooknum,
+ const struct xt_target *target, const void *targinfo)
+{
+ const struct xt_tos_target_info *info = targinfo;
+ struct ipv6hdr *iph = ipv6_hdr(skb);
+ u_int8_t orig, nv;
+
+ orig = ipv6_get_dsfield(iph);
+ nv = (orig & info->tos_mask) ^ info->tos_value;
+
+ if (orig != nv) {
+ if (!skb_make_writable(skb, sizeof(struct iphdr)))
+ return NF_DROP;
+ iph = ipv6_hdr(skb);
+ ipv6_change_dsfield(iph, 0, nv);
+ }
+
+ return XT_CONTINUE;
+}
+
static struct xt_target dscp_tg_reg[] __read_mostly = {
{
.name = "DSCP",
.table = "mangle",
.me = THIS_MODULE,
},
+ {
+ .name = "TOS",
+ .revision = 0,
+ .family = AF_INET,
+ .table = "mangle",
+ .target = tos_tg_v0,
+ .targetsize = sizeof(struct ipt_tos_target_info),
+ .checkentry = tos_tg_check_v0,
+ .me = THIS_MODULE,
+ },
+ {
+ .name = "TOS",
+ .revision = 1,
+ .family = AF_INET,
+ .table = "mangle",
+ .target = tos_tg,
+ .targetsize = sizeof(struct xt_tos_target_info),
+ .me = THIS_MODULE,
+ },
+ {
+ .name = "TOS",
+ .revision = 1,
+ .family = AF_INET6,
+ .table = "mangle",
+ .target = tos_tg6,
+ .targetsize = sizeof(struct xt_tos_target_info),
+ .me = THIS_MODULE,
+ },
};
static int __init dscp_tg_init(void)