C++ (Cpp) nf_ct_defrag_user示例

示例#1

文件： nf_defrag_ipv4.c 项目： DenisLug/mptcp

static unsigned int ipv4_conntrack_defrag(const struct nf_hook_ops *ops,
					  struct sk_buff *skb,
					  const struct nf_hook_state *state)
{
	struct sock *sk = skb->sk;
	struct inet_sock *inet = inet_sk(skb->sk);

	if (sk && (sk->sk_family == PF_INET) &&
	    inet->nodefrag)
		return NF_ACCEPT;

#if IS_ENABLED(CONFIG_NF_CONNTRACK)
#if !IS_ENABLED(CONFIG_NF_NAT)
	/* Previously seen (loopback)?  Ignore.  Do this before
	   fragment check. */
	if (skb->nfct && !nf_ct_is_template((struct nf_conn *)skb->nfct))
		return NF_ACCEPT;
#endif
#endif
	/* Gather fragments. */
	if (ip_is_fragment(ip_hdr(skb))) {
		enum ip_defrag_users user =
			nf_ct_defrag_user(ops->hooknum, skb);

		if (nf_ct_ipv4_gather_frags(skb, user))
			return NF_STOLEN;
	}
	return NF_ACCEPT;
}

示例#2

文件： nf_defrag_ipv4.c 项目： andy-padavan/rt-n56u

static unsigned int ipv4_conntrack_defrag(unsigned int hooknum,
					  struct sk_buff *skb,
					  const struct net_device *in,
					  const struct net_device *out,
					  int (*okfn)(struct sk_buff *))
{
	struct sock *sk = skb->sk;
	struct inet_sock *inet = inet_sk(skb->sk);

	if (sk && (sk->sk_family == PF_INET) &&
	    inet->nodefrag)
		return NF_ACCEPT;

#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
#if !defined(CONFIG_NF_NAT) && !defined(CONFIG_NF_NAT_MODULE)
	/* Previously seen (loopback)?  Ignore.  Do this before
	   fragment check. */
	if (skb->nfct && !nf_ct_is_template((struct nf_conn *)skb->nfct))
		return NF_ACCEPT;
#endif
#endif
	/* Gather fragments. */
	if (ip_is_fragment(ip_hdr(skb))) {
		enum ip_defrag_users user = nf_ct_defrag_user(hooknum, skb);
		if (nf_ct_ipv4_gather_frags(skb, user))
			return NF_STOLEN;
	}
	return NF_ACCEPT;
}

示例#3

文件： nf_defrag_ipv4.c 项目： Chingliu/Reading-and-comprehense-linux-Kernel-network-protocol-stack

//只有当IP分片重组成功时，nf_ct_ipv4_gather_frags才会返回为0。也就是说，当IP分片重组不成功，即IP分片被kernel分片模块缓存时，该函数返回为NF_STOLEN。
unsigned int ipv4_conntrack_defrag2(unsigned int hooknum,
					  struct sk_buff *skb)
{
#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
#if !defined(CONFIG_NF_NAT) && !defined(CONFIG_NF_NAT_MODULE)
	/* Previously seen (loopback)?  Ignore.  Do this before
	   fragment check. */
	if (skb->nfct && !nf_ct_is_template((struct nf_conn *)skb->nfct))
		return NF_ACCEPT;
#endif
#endif
	/* Gather fragments. */
	if (ip_hdr(skb)->frag_off & htons(IP_MF | IP_OFFSET)) {
		enum ip_defrag_users user = nf_ct_defrag_user(hooknum, skb);
		if (nf_ct_ipv4_gather_frags(skb, user))
			return NF_STOLEN;
	}
	return NF_ACCEPT;
}