C++ (Cpp) nf_csum_replace2 Examples

Example #1

File: ipt_ECN.c Project: dycforever/sourceReading

/* set ECT codepoint from IP header.
 * 	return false if there was an error. */
static inline bool
set_ect_ip(struct sk_buff *skb, const struct ipt_ECN_info *einfo)
{
	struct iphdr *iph = ip_hdr(skb);

	if ((iph->tos & IPT_ECN_IP_MASK) != (einfo->ip_ect & IPT_ECN_IP_MASK)) {
		__u8 oldtos;
		if (!skb_make_writable(skb, sizeof(struct iphdr)))
			return false;
		iph = ip_hdr(skb);
		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 true;
}

Example #2

File: ipt_ECN.c Project: WiseMan787/ralink_sdk

/* set ECT codepoint from IP header.
 * 	return 0 if there was an error. */
static inline int
set_ect_ip(struct sk_buff **pskb, const struct ipt_ECN_info *einfo)
{
	struct iphdr *iph = (*pskb)->nh.iph;

	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;
		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;
}

Example #3

File: ipt_TOS.c Project: IgnasD/Tomato-RAF

static unsigned int
target(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 *tosinfo = targinfo;
	struct iphdr *iph = ip_hdr(skb);

	if ((iph->tos & IPTOS_TOS_MASK) != tosinfo->tos) {
		__u8 oldtos;
		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) | tosinfo->tos;
		nf_csum_replace2(&iph->check, htons(oldtos), htons(iph->tos));
	}
	return XT_CONTINUE;
}