static inline int
set_ect_ip(struct sk_buff **pskb, const struct ipt_ECN_info *einfo)
{
- if (((*pskb)->nh.iph->tos & IPT_ECN_IP_MASK)
- != (einfo->ip_ect & IPT_ECN_IP_MASK)) {
- u_int16_t diffs[2];
+ struct iphdr *iph = (*pskb)->nh.iph;
- if (!skb_ip_make_writable(pskb, sizeof(struct iphdr)))
+ if ((iph->tos & IPT_ECN_IP_MASK) != (einfo->ip_ect & IPT_ECN_IP_MASK)) {
+ __u8 oldtos;
+ if (!skb_make_writable(pskb, sizeof(struct iphdr)))
return 0;
-
- diffs[0] = htons((*pskb)->nh.iph->tos) ^ 0xFFFF;
- (*pskb)->nh.iph->tos &= ~IPT_ECN_IP_MASK;
- (*pskb)->nh.iph->tos |= (einfo->ip_ect & IPT_ECN_IP_MASK);
- diffs[1] = htons((*pskb)->nh.iph->tos);
- (*pskb)->nh.iph->check
- = csum_fold(csum_partial((char *)diffs,
- sizeof(diffs),
- (*pskb)->nh.iph->check
- ^0xFFFF));
- (*pskb)->nfcache |= NFC_ALTERED;
+ iph = (*pskb)->nh.iph;
+ oldtos = iph->tos;
+ iph->tos &= ~IPT_ECN_IP_MASK;
+ iph->tos |= (einfo->ip_ect & IPT_ECN_IP_MASK);
+ nf_csum_replace2(&iph->check, htons(oldtos), htons(iph->tos));
}
return 1;
}
/* Return 0 if there was an error. */
static inline int
-set_ect_tcp(struct sk_buff **pskb, const struct ipt_ECN_info *einfo, int inward)
+set_ect_tcp(struct sk_buff **pskb, const struct ipt_ECN_info *einfo)
{
- struct tcphdr _tcph, *th;
- u_int16_t diffs[2];
+ struct tcphdr _tcph, *tcph;
+ __be16 oldval;
/* Not enought header? */
- th = skb_header_pointer(*pskb, (*pskb)->nh.iph->ihl*4,
- sizeof(_tcph), &_tcph);
- if (th == NULL)
+ tcph = skb_header_pointer(*pskb, (*pskb)->nh.iph->ihl*4,
+ sizeof(_tcph), &_tcph);
+ if (!tcph)
return 0;
- diffs[0] = ((u_int16_t *)th)[6];
- if (einfo->operation & IPT_ECN_OP_SET_ECE)
- th->ece = einfo->proto.tcp.ece;
+ if ((!(einfo->operation & IPT_ECN_OP_SET_ECE) ||
+ tcph->ece == einfo->proto.tcp.ece) &&
+ ((!(einfo->operation & IPT_ECN_OP_SET_CWR) ||
+ tcph->cwr == einfo->proto.tcp.cwr)))
+ return 1;
+
+ if (!skb_make_writable(pskb, (*pskb)->nh.iph->ihl*4+sizeof(*tcph)))
+ return 0;
+ tcph = (void *)(*pskb)->nh.iph + (*pskb)->nh.iph->ihl*4;
+ oldval = ((__be16 *)tcph)[6];
+ if (einfo->operation & IPT_ECN_OP_SET_ECE)
+ tcph->ece = einfo->proto.tcp.ece;
if (einfo->operation & IPT_ECN_OP_SET_CWR)
- th->cwr = einfo->proto.tcp.cwr;
- diffs[1] = ((u_int16_t *)&th)[6];
-
- /* Only mangle if it's changed. */
- if (diffs[0] != diffs[1]) {
- diffs[0] = diffs[0] ^ 0xFFFF;
- if (!skb_ip_make_writable(pskb,
- (*pskb)->nh.iph->ihl*4+sizeof(_tcph)))
- return 0;
+ tcph->cwr = einfo->proto.tcp.cwr;
- if (th != &_tcph)
- memcpy(&_tcph, th, sizeof(_tcph));
-
- if ((*pskb)->ip_summed != CHECKSUM_HW)
- _tcph.check = csum_fold(csum_partial((char *)diffs,
- sizeof(diffs),
- _tcph.check^0xFFFF));
- memcpy((*pskb)->data + (*pskb)->nh.iph->ihl*4,
- &_tcph, sizeof(_tcph));
- if ((*pskb)->ip_summed == CHECKSUM_HW)
- if (skb_checksum_help(pskb, inward))
- return 0;
- (*pskb)->nfcache |= NFC_ALTERED;
- }
+ nf_proto_csum_replace2(&tcph->check, *pskb,
+ oldval, ((__be16 *)tcph)[6], 0);
return 1;
}
const struct net_device *in,
const struct net_device *out,
unsigned int hooknum,
- const void *targinfo,
- void *userinfo)
+ const struct xt_target *target,
+ const void *targinfo)
{
const struct ipt_ECN_info *einfo = targinfo;
if (einfo->operation & (IPT_ECN_OP_SET_ECE | IPT_ECN_OP_SET_CWR)
&& (*pskb)->nh.iph->protocol == IPPROTO_TCP)
- if (!set_ect_tcp(pskb, einfo, (out == NULL)))
+ if (!set_ect_tcp(pskb, einfo))
return NF_DROP;
return IPT_CONTINUE;
static int
checkentry(const char *tablename,
- const struct ipt_entry *e,
+ const void *e_void,
+ const struct xt_target *target,
void *targinfo,
- unsigned int targinfosize,
unsigned int hook_mask)
{
const struct ipt_ECN_info *einfo = (struct ipt_ECN_info *)targinfo;
-
- if (targinfosize != IPT_ALIGN(sizeof(struct ipt_ECN_info))) {
- printk(KERN_WARNING "ECN: targinfosize %u != %Zu\n",
- targinfosize,
- IPT_ALIGN(sizeof(struct ipt_ECN_info)));
- return 0;
- }
-
- if (strcmp(tablename, "mangle") != 0) {
- printk(KERN_WARNING "ECN: can only be called from \"mangle\" table, not \"%s\"\n", tablename);
- return 0;
- }
+ const struct ipt_entry *e = e_void;
if (einfo->operation & IPT_ECN_OP_MASK) {
printk(KERN_WARNING "ECN: unsupported ECN operation %x\n",
einfo->ip_ect);
return 0;
}
-
if ((einfo->operation & (IPT_ECN_OP_SET_ECE|IPT_ECN_OP_SET_CWR))
- && e->ip.proto != IPPROTO_TCP) {
+ && (e->ip.proto != IPPROTO_TCP || (e->ip.invflags & IPT_INV_PROTO))) {
printk(KERN_WARNING "ECN: cannot use TCP operations on a "
"non-tcp rule\n");
return 0;
}
-
return 1;
}
static struct ipt_target ipt_ecn_reg = {
.name = "ECN",
.target = target,
+ .targetsize = sizeof(struct ipt_ECN_info),
+ .table = "mangle",
.checkentry = checkentry,
.me = THIS_MODULE,
};
-static int __init init(void)
+static int __init ipt_ecn_init(void)
{
return ipt_register_target(&ipt_ecn_reg);
}
-static void __exit fini(void)
+static void __exit ipt_ecn_fini(void)
{
ipt_unregister_target(&ipt_ecn_reg);
}
-module_init(init);
-module_exit(fini);
+module_init(ipt_ecn_init);
+module_exit(ipt_ecn_fini);