Пример #1
0
/*
 *		Add an ip header to a skbuff and send it out.
 *
 */
int ip_build_and_send_pkt(struct sk_buff *skb, struct sock *sk,
			  __be32 saddr, __be32 daddr, struct ip_options_rcu *opt)
{
	struct inet_sock *inet = inet_sk(sk);
	struct rtable *rt = skb_rtable(skb);
	struct iphdr *iph;

	/* Build the IP header. */
	skb_push(skb, sizeof(struct iphdr) + (opt ? opt->opt.optlen : 0));
	skb_reset_network_header(skb);
	iph = ip_hdr(skb);
	iph->version  = 4;
	iph->ihl      = 5;
	iph->tos      = inet->tos;
	if (ip_dont_fragment(sk, &rt->dst))
		iph->frag_off = htons(IP_DF);
	else
		iph->frag_off = 0;
	iph->ttl      = ip_select_ttl(inet, &rt->dst);
	iph->daddr    = (opt && opt->opt.srr ? opt->opt.faddr : daddr);
	iph->saddr    = saddr;
	iph->protocol = sk->sk_protocol;
	ip_select_ident(skb, sk);

	if (opt && opt->opt.optlen) {
		iph->ihl += opt->opt.optlen>>2;
		ip_options_build(skb, &opt->opt, daddr, rt, 0);
	}
Пример #2
0
/* 
 *		Add an ip header to a skbuff and send it out.
 *
 */
int ip_build_and_send_pkt(struct sk_buff *skb, struct sock *sk,
			  u32 saddr, u32 daddr, struct ip_options *opt)
{
	struct inet_sock *inet = inet_sk(sk);
	struct rtable *rt = (struct rtable *)skb->dst;
	struct iphdr *iph;

	/* Build the IP header. */
	if (opt)
		iph=(struct iphdr *)skb_push(skb,sizeof(struct iphdr) + opt->optlen);
	else
		iph=(struct iphdr *)skb_push(skb,sizeof(struct iphdr));

	iph->version  = 4;
	iph->ihl      = 5;
	iph->tos      = inet->tos;
	if (ip_dont_fragment(sk, &rt->u.dst))
		iph->frag_off = htons(IP_DF);
	else
		iph->frag_off = 0;
	iph->ttl      = ip_select_ttl(inet, &rt->u.dst);
	iph->daddr    = rt->rt_dst;
	iph->saddr    = rt->rt_src;
	iph->protocol = sk->sk_protocol;
	iph->tot_len  = htons(skb->len);
	ip_select_ident(iph, &rt->u.dst, sk);
	skb->nh.iph   = iph;

	if (opt && opt->optlen) {
		iph->ihl += opt->optlen>>2;
		ip_options_build(skb, opt, daddr, rt, 0);
	}
Пример #3
0
int ip_build_xmit(struct sock *sk,
		   void getfrag (const void *,
				 __u32,
				 char *,
				 unsigned int,	
				 unsigned int),
		   const void *frag,
		   unsigned short int length,
		   __u32 daddr,
		   __u32 user_saddr,
		   struct options * opt,
		   int flags,
		   int type,
		   int noblock) 
{
	struct rtable *rt;
	unsigned int fraglen, maxfraglen, fragheaderlen;
	int offset, mf;
	__u32 saddr;
	unsigned short id;
	struct iphdr *iph;
	__u32 raddr;
	struct device *dev = NULL;
	struct hh_cache * hh=NULL;
	int nfrags=0;
	__u32 true_daddr = daddr;

	if (opt && opt->srr && !sk->ip_hdrincl)
	  daddr = opt->faddr;
	
	ip_statistics.IpOutRequests++;

#ifdef CONFIG_IP_MULTICAST	
	if(MULTICAST(daddr) && *sk->ip_mc_name)
	{
		dev=dev_get(sk->ip_mc_name);
		if(!dev)
			return -ENODEV;
		rt=NULL;
		if (sk->saddr && (!LOOPBACK(sk->saddr) || LOOPBACK(daddr)))
			saddr = sk->saddr;
		else
			saddr = dev->pa_addr;
	}
	else
	{
#endif	
		rt = ip_check_route(&sk->ip_route_cache, daddr,
				    sk->localroute || (flags&MSG_DONTROUTE) ||
				    (opt && opt->is_strictroute), sk->bound_device);
		if (rt == NULL) 
		{
			ip_statistics.IpOutNoRoutes++;
			return(-ENETUNREACH);
		}
		saddr = rt->rt_src;

		hh = rt->rt_hh;
	
		if (sk->saddr && (!LOOPBACK(sk->saddr) || LOOPBACK(daddr)))
			saddr = sk->saddr;
			
		dev=rt->rt_dev;
#ifdef CONFIG_IP_MULTICAST
	}
	if (rt && !dev)
		dev = rt->rt_dev;
#endif		
	if (user_saddr)
		saddr = user_saddr;

	raddr = rt ? rt->rt_gateway : daddr;
	/*
	 *	Now compute the buffer space we require
	 */ 
	 
	/*
	 *	Try the simple case first. This leaves broadcast, multicast, fragmented frames, and by
	 *	choice RAW frames within 20 bytes of maximum size(rare) to the long path
	 */

	if (!sk->ip_hdrincl) {
		length += sizeof(struct iphdr);
		if (opt) {
			/* make sure not to exceed maximum packet size */
			if (0xffff - length < opt->optlen)
				return -EMSGSIZE;
			length += opt->optlen;
		}
	}

	if(length <= dev->mtu && !MULTICAST(daddr) && daddr!=0xFFFFFFFF && daddr!=dev->pa_brdaddr)
	{	
		int error;
		struct sk_buff *skb=sock_alloc_send_skb(sk, length+15+dev->hard_header_len,0, noblock, &error);
		if(skb==NULL)
		{
			ip_statistics.IpOutDiscards++;
			return error;
		}
		skb->dev=dev;
		skb->protocol = htons(ETH_P_IP);
		skb->free=1;
		skb->when=jiffies;
		skb->sk=sk;
		skb->arp=0;
		skb->saddr=saddr;
		skb->raddr = raddr;
		skb_reserve(skb,(dev->hard_header_len+15)&~15);
		if (hh)
		{
			skb->arp=1;
			memcpy(skb_push(skb,dev->hard_header_len),hh->hh_data,dev->hard_header_len);
			if (!hh->hh_uptodate)
			{
				skb->arp = 0;
#if RT_CACHE_DEBUG >= 2
				printk("ip_build_xmit: hh miss %08x via %08x\n", rt->rt_dst, rt->rt_gateway);
#endif				
			}
		}
		else if(dev->hard_header)
		{
			if(dev->hard_header(skb,dev,ETH_P_IP,NULL,NULL,0)>0)
				skb->arp=1;
		}
		else
			skb->arp=1;
		skb->ip_hdr=iph=(struct iphdr *)skb_put(skb,length);
		dev_lock_list();
		if(!sk->ip_hdrincl)
		{
			iph->version=4;
			iph->ihl=5;
			iph->tos=sk->ip_tos;
			iph->tot_len = htons(length);
			iph->id=htons(ip_id_count++);
			iph->frag_off = 0;
			iph->ttl=sk->ip_ttl;
			iph->protocol=type;
			iph->saddr=saddr;
			iph->daddr=daddr;
			if (opt) 
			{
				iph->ihl += opt->optlen>>2;
				ip_options_build(skb, opt,
						 true_daddr, dev->pa_addr, 0);
			}
			iph->check=0;
			iph->check = ip_fast_csum((unsigned char *)iph, iph->ihl);
			getfrag(frag,saddr,((char *)iph)+iph->ihl*4,0, length-iph->ihl*4);
		}
Пример #4
0
/*
 * This routine builds the appropriate hardware/IP headers for
 * the routine.  It assumes that if *dev != NULL then the
 * protocol knows what it's doing, otherwise it uses the
 * routing/ARP tables to select a device struct.
 */
int ip_build_header(struct sk_buff *skb, __u32 saddr, __u32 daddr,
		struct device **dev, int type, struct options *opt,
		int len, int tos, int ttl, struct rtable ** rp)
{
	struct rtable *rt;
	__u32 raddr;
	int tmp;
	struct iphdr *iph;
	__u32 final_daddr = daddr;


	if (opt && opt->srr)
		daddr = opt->faddr;

	/*
	 *	See if we need to look up the device.
	 */

#ifdef CONFIG_IP_MULTICAST	
	if(MULTICAST(daddr) && *dev==NULL && skb->sk && *skb->sk->ip_mc_name)
		*dev=dev_get(skb->sk->ip_mc_name);
#endif
	if (rp)
	{
		rt = ip_check_route(rp, daddr, skb->localroute, *dev);
		/*
		 * If rp != NULL rt_put following below should not
		 * release route, so that...
		 */
		if (rt)
			atomic_inc(&rt->rt_refcnt);
	}
	else
		rt = ip_rt_route(daddr, skb->localroute, *dev);


	if (*dev == NULL)
	{
		if (rt == NULL)
		{
			ip_statistics.IpOutNoRoutes++;
			return(-ENETUNREACH);
		}

		*dev = rt->rt_dev;
	}

	if ((LOOPBACK(saddr) && !LOOPBACK(daddr)) || !saddr)
		saddr = rt ? rt->rt_src : (*dev)->pa_addr;

	raddr = rt ? rt->rt_gateway : daddr;

	if (opt && opt->is_strictroute && rt && (rt->rt_flags & RTF_GATEWAY))
	{
		ip_rt_put(rt);
		ip_statistics.IpOutNoRoutes++;
		return -ENETUNREACH;
	}

	/*
	 *	Now build the MAC header.
	 */

	if (type==IPPROTO_TCP)
		tmp = ip_send_room(rt, skb, raddr, len, *dev, saddr);
	else
		tmp = ip_send(rt, skb, raddr, len, *dev, saddr);

	ip_rt_put(rt);

	/*
	 *	Book keeping
	 */

	skb->dev = *dev;
	skb->saddr = saddr;
	
	/*
	 *	Now build the IP header.
	 */

	/*
	 *	If we are using IPPROTO_RAW, then we don't need an IP header, since
	 *	one is being supplied to us by the user
	 */

	if(type == IPPROTO_RAW)
		return (tmp);

	/*
	 *	Build the IP addresses
	 */
	 
	if (opt)
		iph=(struct iphdr *)skb_put(skb,sizeof(struct iphdr) + opt->optlen);
	else
		iph=(struct iphdr *)skb_put(skb,sizeof(struct iphdr));

	iph->version  = 4;
	iph->ihl      = 5;
	iph->tos      = tos;
	iph->frag_off = 0;
	iph->ttl      = ttl;
	iph->daddr    = daddr;
	iph->saddr    = saddr;
	iph->protocol = type;
	skb->ip_hdr   = iph;

	if (!opt || !opt->optlen)
		return sizeof(struct iphdr) + tmp;
	iph->ihl += opt->optlen>>2;
	ip_options_build(skb, opt, final_daddr, (*dev)->pa_addr, 0);
	return iph->ihl*4 + tmp;
}