Esempio n. 1
0
static int ip6_tnl_xmit2(struct sk_buff *skb,
			 struct net_device *dev,
			 __u8 dsfield,
			 struct flowi *fl,
			 int encap_limit,
			 __u32 *pmtu)
{
	struct net *net = dev_net(dev);
	struct ip6_tnl *t = netdev_priv(dev);
	struct net_device_stats *stats = &t->dev->stats;
	struct ipv6hdr *ipv6h = ipv6_hdr(skb);
	struct ipv6_tel_txoption opt;
	struct dst_entry *dst;
	struct net_device *tdev;
	int mtu;
	unsigned int max_headroom = sizeof(struct ipv6hdr);
	u8 proto;
	int err = -1;
	int pkt_len;
    int check = 0;

	if ((dst = ip6_tnl_dst_check(t)) != NULL)
		dst_hold(dst);
	else {
		dst = ip6_route_output(net, NULL, fl);

		if (dst->error || xfrm_lookup(net, &dst, fl, NULL, 0) < 0)
			goto tx_err_link_failure;
	}

	tdev = dst->dev;
    //printk("tunnel-->dst->dev name:%s, skb->len:%d, tunnel proto:%d\n", tdev->name, skb->len, t->parms.proto);

	if (tdev == dev) {
		stats->collisions++;
		if (net_ratelimit())
			printk(KERN_WARNING
			       "%s: Local routing loop detected!\n",
			       t->parms.name);
		goto tx_err_dst_release;
	}
	mtu = dst_mtu(dst) - sizeof (*ipv6h);
	if (encap_limit >= 0) {
		max_headroom += 8;
		mtu -= 8;
	}
    
	if (mtu < IPV6_MIN_MTU)
		mtu = IPV6_MIN_MTU;
	if (skb->dst)
		skb->dst->ops->update_pmtu(skb->dst, mtu);

    /*start by d00191326 rfc 2473:Dslite报文不进行V4分片而进行V6分片*/
    if ((t->parms.proto == IPPROTO_IPIP && ip_hdr(skb)->frag_off&htons(IP_DF))
        || t->parms.proto == IPPROTO_IPV6){
        check = 1;
    }
    /*end by d00191326 rfc 2473:Dslite报文不进行V4分片而进行V6分片*/
    
	if (skb->len > mtu && check) {
		*pmtu = mtu;
		err = -EMSGSIZE;
		goto tx_err_dst_release;
	}

	/*
	 * Okay, now see if we can stuff it in the buffer as-is.
	 */
	max_headroom += LL_RESERVED_SPACE(tdev);

	if (skb_headroom(skb) < max_headroom || skb_shared(skb) ||
	    (skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
		struct sk_buff *new_skb;

		if (!(new_skb = skb_realloc_headroom(skb, max_headroom)))
			goto tx_err_dst_release;

		if (skb->sk)
			skb_set_owner_w(new_skb, skb->sk);
		kfree_skb(skb);
		skb = new_skb;
	}
	dst_release(skb->dst);
	skb->dst = dst_clone(dst);

	skb->transport_header = skb->network_header;
    skb->local_df = 1;

	proto = fl->proto;
	if (encap_limit >= 0) {
		init_tel_txopt(&opt, encap_limit);
		ipv6_push_nfrag_opts(skb, &opt.ops, &proto, NULL);
	}
	skb_push(skb, sizeof(struct ipv6hdr));
	skb_reset_network_header(skb);
	ipv6h = ipv6_hdr(skb);
	*(__be32*)ipv6h = fl->fl6_flowlabel | htonl(0x60000000);
	dsfield = INET_ECN_encapsulate(dsfield, dsfield);
	ipv6_change_dsfield(ipv6h, ~INET_ECN_MASK, dsfield);
	ipv6h->hop_limit = t->parms.hop_limit;
	ipv6h->nexthdr = proto;
	ipv6_addr_copy(&ipv6h->saddr, &fl->fl6_src);
	ipv6_addr_copy(&ipv6h->daddr, &fl->fl6_dst);
	nf_reset(skb);
	pkt_len = skb->len;
	err = ip6_local_out(skb);

	if (net_xmit_eval(err) == 0) {
		stats->tx_bytes += pkt_len;
		stats->tx_packets++;
	} else {
		stats->tx_errors++;
		stats->tx_aborted_errors++;
	}
	ip6_tnl_dst_store(t, dst);
	return 0;
tx_err_link_failure:
	stats->tx_carrier_errors++;
	dst_link_failure(skb);
tx_err_dst_release:
	dst_release(dst);
	return err;
}
Esempio n. 2
0
static struct sock *dccp_v6_request_recv_sock(struct sock *sk,
					      struct sk_buff *skb,
					      struct request_sock *req,
					      struct dst_entry *dst)
{
	struct inet6_request_sock *ireq6 = inet6_rsk(req);
	struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
	struct inet_sock *newinet;
	struct dccp_sock *newdp;
	struct dccp6_sock *newdp6;
	struct sock *newsk;
	struct ipv6_txoptions *opt;

	if (skb->protocol == htons(ETH_P_IP)) {
		/*
		 *	v6 mapped
		 */
		newsk = dccp_v4_request_recv_sock(sk, skb, req, dst);
		if (newsk == NULL)
			return NULL;

		newdp6 = (struct dccp6_sock *)newsk;
		newdp = dccp_sk(newsk);
		newinet = inet_sk(newsk);
		newinet->pinet6 = &newdp6->inet6;
		newnp = inet6_sk(newsk);

		memcpy(newnp, np, sizeof(struct ipv6_pinfo));

		ipv6_addr_set(&newnp->daddr, 0, 0, htonl(0x0000FFFF),
			      newinet->daddr);

		ipv6_addr_set(&newnp->saddr, 0, 0, htonl(0x0000FFFF),
			      newinet->saddr);

		ipv6_addr_copy(&newnp->rcv_saddr, &newnp->saddr);

		inet_csk(newsk)->icsk_af_ops = &dccp_ipv6_mapped;
		newsk->sk_backlog_rcv = dccp_v4_do_rcv;
		newnp->pktoptions  = NULL;
		newnp->opt	   = NULL;
		newnp->mcast_oif   = inet6_iif(skb);
		newnp->mcast_hops  = ipv6_hdr(skb)->hop_limit;

		/*
		 * No need to charge this sock to the relevant IPv6 refcnt debug socks count
		 * here, dccp_create_openreq_child now does this for us, see the comment in
		 * that function for the gory details. -acme
		 */

		/* It is tricky place. Until this moment IPv4 tcp
		   worked with IPv6 icsk.icsk_af_ops.
		   Sync it now.
		 */
		dccp_sync_mss(newsk, inet_csk(newsk)->icsk_pmtu_cookie);

		return newsk;
	}

	opt = np->opt;

	if (sk_acceptq_is_full(sk))
		goto out_overflow;

	if (dst == NULL) {
		struct in6_addr *final_p = NULL, final;
		struct flowi fl;

		memset(&fl, 0, sizeof(fl));
		fl.proto = IPPROTO_DCCP;
		ipv6_addr_copy(&fl.fl6_dst, &ireq6->rmt_addr);
		if (opt != NULL && opt->srcrt != NULL) {
			const struct rt0_hdr *rt0 = (struct rt0_hdr *)opt->srcrt;

			ipv6_addr_copy(&final, &fl.fl6_dst);
			ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
			final_p = &final;
		}
		ipv6_addr_copy(&fl.fl6_src, &ireq6->loc_addr);
		fl.oif = sk->sk_bound_dev_if;
		fl.fl_ip_dport = inet_rsk(req)->rmt_port;
		fl.fl_ip_sport = inet_rsk(req)->loc_port;
		security_sk_classify_flow(sk, &fl);

		if (ip6_dst_lookup(sk, &dst, &fl))
			goto out;

		if (final_p)
			ipv6_addr_copy(&fl.fl6_dst, final_p);

		if ((xfrm_lookup(sock_net(sk), &dst, &fl, sk, 0)) < 0)
			goto out;
	}

	newsk = dccp_create_openreq_child(sk, req, skb);
	if (newsk == NULL)
		goto out;

	/*
	 * No need to charge this sock to the relevant IPv6 refcnt debug socks
	 * count here, dccp_create_openreq_child now does this for us, see the
	 * comment in that function for the gory details. -acme
	 */

	__ip6_dst_store(newsk, dst, NULL, NULL);
	newsk->sk_route_caps = dst->dev->features & ~(NETIF_F_IP_CSUM |
						      NETIF_F_TSO);
	if (!sysctl_tcp_use_sg)
		newsk->sk_route_caps &= ~NETIF_F_SG;
	newdp6 = (struct dccp6_sock *)newsk;
	newinet = inet_sk(newsk);
	newinet->pinet6 = &newdp6->inet6;
	newdp = dccp_sk(newsk);
	newnp = inet6_sk(newsk);

	memcpy(newnp, np, sizeof(struct ipv6_pinfo));

	ipv6_addr_copy(&newnp->daddr, &ireq6->rmt_addr);
	ipv6_addr_copy(&newnp->saddr, &ireq6->loc_addr);
	ipv6_addr_copy(&newnp->rcv_saddr, &ireq6->loc_addr);
	newsk->sk_bound_dev_if = ireq6->iif;

	/* Now IPv6 options...

	   First: no IPv4 options.
	 */
	newinet->opt = NULL;

	/* Clone RX bits */
	newnp->rxopt.all = np->rxopt.all;

	/* Clone pktoptions received with SYN */
	newnp->pktoptions = NULL;
	if (ireq6->pktopts != NULL) {
		newnp->pktoptions = skb_clone(ireq6->pktopts, GFP_ATOMIC);
		kfree_skb(ireq6->pktopts);
		ireq6->pktopts = NULL;
		if (newnp->pktoptions)
			skb_set_owner_r(newnp->pktoptions, newsk);
	}
	newnp->opt	  = NULL;
	newnp->mcast_oif  = inet6_iif(skb);
	newnp->mcast_hops = ipv6_hdr(skb)->hop_limit;

	/*
	 * Clone native IPv6 options from listening socket (if any)
	 *
	 * Yes, keeping reference count would be much more clever, but we make
	 * one more one thing there: reattach optmem to newsk.
	 */
	if (opt != NULL) {
		newnp->opt = ipv6_dup_options(newsk, opt);
		if (opt != np->opt)
			sock_kfree_s(sk, opt, opt->tot_len);
	}

	inet_csk(newsk)->icsk_ext_hdr_len = 0;
	if (newnp->opt != NULL)
		inet_csk(newsk)->icsk_ext_hdr_len = (newnp->opt->opt_nflen +
						     newnp->opt->opt_flen);

	dccp_sync_mss(newsk, dst_mtu(dst));

	newinet->daddr = newinet->saddr = newinet->rcv_saddr = LOOPBACK4_IPV6;

	__inet6_hash(newsk);
	__inet_inherit_port(sk, newsk);

	return newsk;

out_overflow:
	NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS);
out:
	NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS);
	if (opt != NULL && opt != np->opt)
		sock_kfree_s(sk, opt, opt->tot_len);
	dst_release(dst);
	return NULL;
}
Esempio n. 3
0
static void dccp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
			u8 type, u8 code, int offset, __be32 info)
{
	struct ipv6hdr *hdr = (struct ipv6hdr *)skb->data;
	const struct dccp_hdr *dh = (struct dccp_hdr *)(skb->data + offset);
	struct dccp_sock *dp;
	struct ipv6_pinfo *np;
	struct sock *sk;
	int err;
	__u64 seq;
	struct net *net = dev_net(skb->dev);

	if (skb->len < offset + sizeof(*dh) ||
	    skb->len < offset + __dccp_basic_hdr_len(dh)) {
		ICMP6_INC_STATS_BH(net, __in6_dev_get(skb->dev),
				   ICMP6_MIB_INERRORS);
		return;
	}

	sk = inet6_lookup(net, &dccp_hashinfo,
			&hdr->daddr, dh->dccph_dport,
			&hdr->saddr, dh->dccph_sport, inet6_iif(skb));

	if (sk == NULL) {
		ICMP6_INC_STATS_BH(net, __in6_dev_get(skb->dev),
				   ICMP6_MIB_INERRORS);
		return;
	}

	if (sk->sk_state == DCCP_TIME_WAIT) {
		inet_twsk_put(inet_twsk(sk));
		return;
	}

	bh_lock_sock(sk);
	if (sock_owned_by_user(sk))
		NET_INC_STATS_BH(net, LINUX_MIB_LOCKDROPPEDICMPS);

	if (sk->sk_state == DCCP_CLOSED)
		goto out;

	dp = dccp_sk(sk);
	seq = dccp_hdr_seq(dh);
	if ((1 << sk->sk_state) & ~(DCCPF_REQUESTING | DCCPF_LISTEN) &&
	    !between48(seq, dp->dccps_awl, dp->dccps_awh)) {
		NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS);
		goto out;
	}

	np = inet6_sk(sk);

	if (type == ICMPV6_PKT_TOOBIG) {
		struct dst_entry *dst = NULL;

		if (sock_owned_by_user(sk))
			goto out;
		if ((1 << sk->sk_state) & (DCCPF_LISTEN | DCCPF_CLOSED))
			goto out;

		/* icmp should have updated the destination cache entry */
		dst = __sk_dst_check(sk, np->dst_cookie);
		if (dst == NULL) {
			struct inet_sock *inet = inet_sk(sk);
			struct flowi fl;

			/* BUGGG_FUTURE: Again, it is not clear how
			   to handle rthdr case. Ignore this complexity
			   for now.
			 */
			memset(&fl, 0, sizeof(fl));
			fl.proto = IPPROTO_DCCP;
			ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
			ipv6_addr_copy(&fl.fl6_src, &np->saddr);
			fl.oif = sk->sk_bound_dev_if;
			fl.fl_ip_dport = inet->dport;
			fl.fl_ip_sport = inet->sport;
			security_sk_classify_flow(sk, &fl);

			err = ip6_dst_lookup(sk, &dst, &fl);
			if (err) {
				sk->sk_err_soft = -err;
				goto out;
			}

			err = xfrm_lookup(net, &dst, &fl, sk, 0);
			if (err < 0) {
				sk->sk_err_soft = -err;
				goto out;
			}
		} else
			dst_hold(dst);

		if (inet_csk(sk)->icsk_pmtu_cookie > dst_mtu(dst)) {
			dccp_sync_mss(sk, dst_mtu(dst));
		} /* else let the usual retransmit timer handle it */
		dst_release(dst);
		goto out;
	}

	icmpv6_err_convert(type, code, &err);

	/* Might be for an request_sock */
	switch (sk->sk_state) {
		struct request_sock *req, **prev;
	case DCCP_LISTEN:
		if (sock_owned_by_user(sk))
			goto out;

		req = inet6_csk_search_req(sk, &prev, dh->dccph_dport,
					   &hdr->daddr, &hdr->saddr,
					   inet6_iif(skb));
		if (req == NULL)
			goto out;

		/*
		 * ICMPs are not backlogged, hence we cannot get an established
		 * socket here.
		 */
		WARN_ON(req->sk != NULL);

		if (seq != dccp_rsk(req)->dreq_iss) {
			NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS);
			goto out;
		}

		inet_csk_reqsk_queue_drop(sk, req, prev);
		goto out;

	case DCCP_REQUESTING:
	case DCCP_RESPOND:  /* Cannot happen.
			       It can, it SYNs are crossed. --ANK */
		if (!sock_owned_by_user(sk)) {
			DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS);
			sk->sk_err = err;
			/*
			 * Wake people up to see the error
			 * (see connect in sock.c)
			 */
			sk->sk_error_report(sk);
			dccp_done(sk);
		} else
			sk->sk_err_soft = err;
		goto out;
	}

	if (!sock_owned_by_user(sk) && np->recverr) {
		sk->sk_err = err;
		sk->sk_error_report(sk);
	} else
		sk->sk_err_soft = err;

out:
	bh_unlock_sock(sk);
	sock_put(sk);
}
Esempio n. 4
0
static void __ndisc_send(struct net_device *dev,
			 struct neighbour *neigh,
			 struct in6_addr *daddr, struct in6_addr *saddr,
			 struct icmp6hdr *icmp6h, struct in6_addr *target,
			 int llinfo, int icmp6_mib_outnd)
{
	struct flowi fl;
	struct dst_entry *dst;
	struct sock *sk = ndisc_socket->sk;
	struct sk_buff *skb;
	struct icmp6hdr *hdr;
	struct inet6_dev *idev;
	int len;
	int err;
	u8 *opt;

	ndisc_flow_init(&fl, icmp6h->icmp6_type, saddr, daddr,
			dev->ifindex);

	dst = ndisc_dst_alloc(dev, neigh, daddr, ip6_output);
	if (!dst)
		return;

	err = xfrm_lookup(&dst, &fl, NULL, 0);
	if (err < 0)
		return;

	if (!dev->addr_len)
		llinfo = 0;

	len = sizeof(struct icmp6hdr) + (target ? sizeof(*target) : 0);
	if (llinfo)
		len += ndisc_opt_addr_space(dev);

	skb = sock_alloc_send_skb(sk,
				  (MAX_HEADER + sizeof(struct ipv6hdr) +
				   len + LL_RESERVED_SPACE(dev)),
				  1, &err);
	if (!skb) {
		ND_PRINTK0(KERN_ERR
			   "ICMPv6 ND: %s() failed to allocate an skb.\n",
			   __FUNCTION__);
		dst_release(dst);
		return;
	}

	skb_reserve(skb, LL_RESERVED_SPACE(dev));
	ip6_nd_hdr(sk, skb, dev, saddr, daddr, IPPROTO_ICMPV6, len);

	skb->transport_header = skb->tail;
	skb_put(skb, len);

	hdr = (struct icmp6hdr *)skb_transport_header(skb);
	memcpy(hdr, icmp6h, sizeof(*hdr));

	opt = skb_transport_header(skb) + sizeof(struct icmp6hdr);
	if (target) {
		ipv6_addr_copy((struct in6_addr *)opt, target);
		opt += sizeof(*target);
	}

	if (llinfo)
		ndisc_fill_addr_option(opt, llinfo, dev->dev_addr,
				       dev->addr_len, dev->type);

	hdr->icmp6_cksum = csum_ipv6_magic(saddr, daddr, len,
					   IPPROTO_ICMPV6,
					   csum_partial((__u8 *) hdr,
							len, 0));

	skb->dst = dst;

	idev = in6_dev_get(dst->dev);
	IP6_INC_STATS(idev, IPSTATS_MIB_OUTREQUESTS);

	err = NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL, dst->dev, dst_output);
	if (!err) {
		ICMP6_INC_STATS(idev, icmp6_mib_outnd);
		ICMP6_INC_STATS(idev, ICMP6_MIB_OUTMSGS);
	}

	if (likely(idev != NULL))
		in6_dev_put(idev);
}
Esempio n. 5
0
static int dccp_v6_send_response(struct sock *sk, struct request_sock *req,
				 struct request_values *rv_unused)
{
	struct inet6_request_sock *ireq6 = inet6_rsk(req);
	struct ipv6_pinfo *np = inet6_sk(sk);
	struct sk_buff *skb;
	struct ipv6_txoptions *opt = NULL;
	struct in6_addr *final_p = NULL, final;
	struct flowi fl;
	int err = -1;
	struct dst_entry *dst;

	memset(&fl, 0, sizeof(fl));
	fl.proto = IPPROTO_DCCP;
	ipv6_addr_copy(&fl.fl6_dst, &ireq6->rmt_addr);
	ipv6_addr_copy(&fl.fl6_src, &ireq6->loc_addr);
	fl.fl6_flowlabel = 0;
	fl.oif = ireq6->iif;
	fl.fl_ip_dport = inet_rsk(req)->rmt_port;
	fl.fl_ip_sport = inet_rsk(req)->loc_port;
	security_req_classify_flow(req, &fl);

	opt = np->opt;

	if (opt != NULL && opt->srcrt != NULL) {
		const struct rt0_hdr *rt0 = (struct rt0_hdr *)opt->srcrt;

		ipv6_addr_copy(&final, &fl.fl6_dst);
		ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
		final_p = &final;
	}

	err = ip6_dst_lookup(sk, &dst, &fl);
	if (err)
		goto done;

	if (final_p)
		ipv6_addr_copy(&fl.fl6_dst, final_p);

	err = xfrm_lookup(sock_net(sk), &dst, &fl, sk, 0);
	if (err < 0)
		goto done;

	skb = dccp_make_response(sk, dst, req);
	if (skb != NULL) {
		struct dccp_hdr *dh = dccp_hdr(skb);

		dh->dccph_checksum = dccp_v6_csum_finish(skb,
							 &ireq6->loc_addr,
							 &ireq6->rmt_addr);
		ipv6_addr_copy(&fl.fl6_dst, &ireq6->rmt_addr);
		err = ip6_xmit(sk, skb, &fl, opt, 0);
		err = net_xmit_eval(err);
	}

done:
	if (opt != NULL && opt != np->opt)
		sock_kfree_s(sk, opt, opt->tot_len);
	dst_release(dst);
	return err;
}
Esempio n. 6
0
static void tcp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
		int type, int code, int offset, __u32 info)
{
	struct ipv6hdr *hdr = (struct ipv6hdr*)skb->data;
	const struct tcphdr *th = (struct tcphdr *)(skb->data+offset);
	struct ipv6_pinfo *np;
	struct sock *sk;
	int err;
	struct tcp_sock *tp; 
	__u32 seq;

	sk = inet6_lookup(&tcp_hashinfo, &hdr->daddr, th->dest, &hdr->saddr,
			  th->source, skb->dev->ifindex);

	if (sk == NULL) {
		ICMP6_INC_STATS_BH(__in6_dev_get(skb->dev), ICMP6_MIB_INERRORS);
		return;
	}

	if (sk->sk_state == TCP_TIME_WAIT) {
		inet_twsk_put(inet_twsk(sk));
		return;
	}

	bh_lock_sock(sk);
	if (sock_owned_by_user(sk))
		NET_INC_STATS_BH(LINUX_MIB_LOCKDROPPEDICMPS);

	if (sk->sk_state == TCP_CLOSE)
		goto out;

	tp = tcp_sk(sk);
	seq = ntohl(th->seq); 
	if (sk->sk_state != TCP_LISTEN &&
	    !between(seq, tp->snd_una, tp->snd_nxt)) {
		NET_INC_STATS_BH(LINUX_MIB_OUTOFWINDOWICMPS);
		goto out;
	}

	np = inet6_sk(sk);

	if (type == ICMPV6_PKT_TOOBIG) {
		struct dst_entry *dst = NULL;

		if (sock_owned_by_user(sk))
			goto out;
		if ((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE))
			goto out;

		/* icmp should have updated the destination cache entry */
		dst = __sk_dst_check(sk, np->dst_cookie);

		if (dst == NULL) {
			struct inet_sock *inet = inet_sk(sk);
			struct flowi fl;

			/* BUGGG_FUTURE: Again, it is not clear how
			   to handle rthdr case. Ignore this complexity
			   for now.
			 */
			memset(&fl, 0, sizeof(fl));
			fl.proto = IPPROTO_TCP;
			ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
			ipv6_addr_copy(&fl.fl6_src, &np->saddr);
			fl.oif = sk->sk_bound_dev_if;
			fl.fl_ip_dport = inet->dport;
			fl.fl_ip_sport = inet->sport;
			security_skb_classify_flow(skb, &fl);

			if ((err = ip6_dst_lookup(sk, &dst, &fl))) {
				sk->sk_err_soft = -err;
				goto out;
			}

			if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0) {
				sk->sk_err_soft = -err;
				goto out;
			}

		} else
			dst_hold(dst);

		if (inet_csk(sk)->icsk_pmtu_cookie > dst_mtu(dst)) {
			tcp_sync_mss(sk, dst_mtu(dst));
			tcp_simple_retransmit(sk);
		} /* else let the usual retransmit timer handle it */
		dst_release(dst);
		goto out;
	}

	icmpv6_err_convert(type, code, &err);

	/* Might be for an request_sock */
	switch (sk->sk_state) {
		struct request_sock *req, **prev;
	case TCP_LISTEN:
		if (sock_owned_by_user(sk))
			goto out;

		req = inet6_csk_search_req(sk, &prev, th->dest, &hdr->daddr,
					   &hdr->saddr, inet6_iif(skb));
		if (!req)
			goto out;

		/* ICMPs are not backlogged, hence we cannot get
		 * an established socket here.
		 */
		BUG_TRAP(req->sk == NULL);

		if (seq != tcp_rsk(req)->snt_isn) {
			NET_INC_STATS_BH(LINUX_MIB_OUTOFWINDOWICMPS);
			goto out;
		}

		inet_csk_reqsk_queue_drop(sk, req, prev);
		goto out;

	case TCP_SYN_SENT:
	case TCP_SYN_RECV:  /* Cannot happen.
			       It can, it SYNs are crossed. --ANK */ 
		if (!sock_owned_by_user(sk)) {
			sk->sk_err = err;
			sk->sk_error_report(sk);		/* Wake people up to see the error (see connect in sock.c) */

			tcp_done(sk);
		} else
			sk->sk_err_soft = err;
		goto out;
	}

	if (!sock_owned_by_user(sk) && np->recverr) {
		sk->sk_err = err;
		sk->sk_error_report(sk);
	} else
		sk->sk_err_soft = err;

out:
	bh_unlock_sock(sk);
	sock_put(sk);
}
Esempio n. 7
0
static int
ip6ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
{
	struct ip6_tnl *t = (struct ip6_tnl *) dev->priv;
	struct net_device_stats *stats = &t->stat;
	struct ipv6hdr *ipv6h = skb->nh.ipv6h;
	int encap_limit = -1;
	struct ipv6_tel_txoption opt;
	__u16 offset;
	struct flowi fl;
	struct dst_entry *dst;
	struct net_device *tdev;
	int mtu;
	int max_headroom = sizeof(struct ipv6hdr);
	u8 proto;
	int err;
	int pkt_len;
	int dsfield;

	if (t->recursion++) {
		stats->collisions++;
		goto tx_err;
	}
	if (skb->protocol != htons(ETH_P_IPV6) ||
	    !ip6_tnl_xmit_ctl(t) || ip6ip6_tnl_addr_conflict(t, ipv6h)) {
		goto tx_err;
	}
	if ((offset = parse_tlv_tnl_enc_lim(skb, skb->nh.raw)) > 0) {
		struct ipv6_tlv_tnl_enc_lim *tel;
		tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->nh.raw[offset];
		if (tel->encap_limit == 0) {
			icmpv6_send(skb, ICMPV6_PARAMPROB,
				    ICMPV6_HDR_FIELD, offset + 2, skb->dev);
			goto tx_err;
		}
		encap_limit = tel->encap_limit - 1;
	} else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) {
		encap_limit = t->parms.encap_limit;
	}
	memcpy(&fl, &t->fl, sizeof (fl));
	fl.iif = ((struct inet6_skb_parm *)skb->cb)->iif;
	proto = fl.proto;

	dsfield = ipv6_get_dsfield(ipv6h);
	if ((t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS))
		fl.fl6_flowlabel |= (*(__u32 *) ipv6h & IPV6_TCLASS_MASK);
	if ((t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL))
		fl.fl6_flowlabel |= (*(__u32 *) ipv6h & IPV6_FLOWLABEL_MASK);

	if ((dst = ip6_tnl_dst_check(t)) != NULL)
		dst_hold(dst);
	else {
		dst = ip6_route_output(NULL, &fl);

		if (dst->error || xfrm_lookup(&dst, &fl, NULL, 0) < 0)
			goto tx_err_link_failure;
	}

	tdev = dst->dev;

	if (tdev == dev) {
		stats->collisions++;
		if (net_ratelimit())
			printk(KERN_WARNING
			       "%s: Local routing loop detected!\n",
			       t->parms.name);
		goto tx_err_dst_release;
	}
	mtu = dst_mtu(dst) - sizeof (*ipv6h);
	if (encap_limit >= 0) {
		max_headroom += 8;
		mtu -= 8;
	}
	if (mtu < IPV6_MIN_MTU)
		mtu = IPV6_MIN_MTU;
	if (skb->dst && mtu < dst_mtu(skb->dst)) {
		struct rt6_info *rt = (struct rt6_info *) skb->dst;
		rt->rt6i_flags |= RTF_MODIFIED;
		rt->u.dst.metrics[RTAX_MTU-1] = mtu;
	}
	if (skb->len > mtu) {
		icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, dev);
		goto tx_err_dst_release;
	}

	/*
	 * Okay, now see if we can stuff it in the buffer as-is.
	 */
	max_headroom += LL_RESERVED_SPACE(tdev);
	
	if (skb_headroom(skb) < max_headroom ||
	    skb_cloned(skb) || skb_shared(skb)) {
		struct sk_buff *new_skb;
		
		if (!(new_skb = skb_realloc_headroom(skb, max_headroom)))
			goto tx_err_dst_release;

		if (skb->sk)
			skb_set_owner_w(new_skb, skb->sk);
		kfree_skb(skb);
		skb = new_skb;
	}
	dst_release(skb->dst);
	skb->dst = dst_clone(dst);

	skb->h.raw = skb->nh.raw;

	if (encap_limit >= 0) {
		init_tel_txopt(&opt, encap_limit);
		ipv6_push_nfrag_opts(skb, &opt.ops, &proto, NULL);
	}
	skb->nh.raw = skb_push(skb, sizeof(struct ipv6hdr));
	ipv6h = skb->nh.ipv6h;
	*(u32*)ipv6h = fl.fl6_flowlabel | htonl(0x60000000);
	dsfield = INET_ECN_encapsulate(0, dsfield);
	ipv6_change_dsfield(ipv6h, ~INET_ECN_MASK, dsfield);
	ipv6h->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
	ipv6h->hop_limit = t->parms.hop_limit;	/*XXX use physical link's mtu */
	ipv6h->nexthdr = proto;
	ipv6_addr_copy(&ipv6h->saddr, &fl.fl6_src);
	ipv6_addr_copy(&ipv6h->daddr, &fl.fl6_dst);
	nf_reset(skb);
	pkt_len = skb->len;
	err = NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL,
		      skb->dst->dev, dst_output);

	if (err == NET_XMIT_SUCCESS || err == NET_XMIT_CN) {
		stats->tx_bytes += pkt_len;
		stats->tx_packets++;
	} else {
		stats->tx_errors++;
		stats->tx_aborted_errors++;
	}
	ip6_tnl_dst_store(t, dst);

	t->recursion--;
	return 0;
tx_err_link_failure:
	stats->tx_carrier_errors++;
	dst_link_failure(skb);
tx_err_dst_release:
	dst_release(dst);
tx_err:
	stats->tx_errors++;
	stats->tx_dropped++;
	kfree_skb(skb);
	t->recursion--;
	return 0;
}
Esempio n. 8
0
int ip6_build_xmit(struct sock *sk, inet_getfrag_t getfrag, const void *data,
		   struct flowi *fl, unsigned length,
		   struct ipv6_txoptions *opt, int hlimit, int flags)
{
	struct ipv6_pinfo *np = &sk->net_pinfo.af_inet6;
	struct in6_addr final_dst_buf, *final_dst = NULL;
	struct dst_entry *dst;
	int err = 0;
	unsigned int pktlength, jumbolen, mtu;

	if (opt && opt->srcrt) {
		struct rt0_hdr *rt0 = (struct rt0_hdr *) opt->srcrt;
		ipv6_addr_copy(&final_dst_buf, &fl->fl6_dst);
		final_dst = &final_dst_buf;
		ipv6_addr_copy(&fl->fl6_dst, rt0->addr);
	}

	if (!fl->oif && ipv6_addr_is_multicast(&fl->fl6_dst))
		fl->oif = np->mcast_oif;

	dst = __sk_dst_check(sk, np->dst_cookie);
	if (dst) {
		struct rt6_info *rt = (struct rt6_info*)dst;

			/* Yes, checking route validity in not connected
			   case is not very simple. Take into account,
			   that we do not support routing by source, TOS,
			   and MSG_DONTROUTE 		--ANK (980726)

			   1. If route was host route, check that
			      cached destination is current.
			      If it is network route, we still may
			      check its validity using saved pointer
			      to the last used address: daddr_cache.
			      We do not want to save whole address now,
			      (because main consumer of this service
			       is tcp, which has not this problem),
			      so that the last trick works only on connected
			      sockets.
			   2. oif also should be the same.
			 */

		if (((rt->rt6i_dst.plen != 128 ||
		      ipv6_addr_cmp(&fl->fl6_dst, &rt->rt6i_dst.addr))
		     && (np->daddr_cache == NULL ||
			 ipv6_addr_cmp(&fl->fl6_dst, np->daddr_cache)))
		    || (fl->oif && fl->oif != dst->dev->ifindex)) {
			dst = NULL;
		} else
			dst_hold(dst);
	}

	if (dst == NULL)
		dst = ip6_route_output(sk, fl);

	if (dst->error) {
		IP6_INC_STATS(Ip6OutNoRoutes);
		dst_release(dst);
		return -ENETUNREACH;
	}

	if (ipv6_addr_any(&fl->fl6_src)) {
		err = ipv6_get_saddr(dst, &fl->fl6_dst, &fl->fl6_src);

		if (err) {
#if IP6_DEBUG >= 2
			printk(KERN_DEBUG "ip6_build_xmit: "
			       "no available source address\n");
#endif
			goto out;
		}
	}
	pktlength = length;

        if (dst) {
		if ((err = xfrm_lookup(&dst, fl, sk, 0)) < 0) {
			dst_release(dst);	
			return -ENETUNREACH;
		}
        }

	if (hlimit < 0) {
		if (ipv6_addr_is_multicast(&fl->fl6_dst))
			hlimit = np->mcast_hops;
		else
			hlimit = np->hop_limit;
		if (hlimit < 0)
			hlimit = dst_metric(dst, RTAX_HOPLIMIT);
	}

	jumbolen = 0;

	if (!sk->protinfo.af_inet.hdrincl) {
		pktlength += sizeof(struct ipv6hdr);
		if (opt)
			pktlength += opt->opt_flen + opt->opt_nflen;

		if (pktlength > sizeof(struct ipv6hdr) + IPV6_MAXPLEN) {
			/* Jumbo datagram.
			   It is assumed, that in the case of hdrincl
			   jumbo option is supplied by user.
			 */
			pktlength += 8;
			jumbolen = pktlength - sizeof(struct ipv6hdr);
		}
	}

	mtu = dst_pmtu(dst);
	if (np->frag_size < mtu) {
		if (np->frag_size)
			mtu = np->frag_size;
		else if (np->pmtudisc == IPV6_PMTUDISC_DONT)
			mtu = IPV6_MIN_MTU;
	}

	/* Critical arithmetic overflow check.
	   FIXME: may gcc optimize it out? --ANK (980726)
	 */
	if (pktlength < length) {
		ipv6_local_error(sk, EMSGSIZE, fl, mtu);
		err = -EMSGSIZE;
		goto out;
	}

	if (flags&MSG_CONFIRM)
		dst_confirm(dst);

	if (pktlength <= mtu) {
		struct sk_buff *skb;
		struct ipv6hdr *hdr;
		struct net_device *dev = dst->dev;

		err = 0;
		if (flags&MSG_PROBE)
			goto out;
		/* alloc skb with mtu as we do in the IPv4 stack for IPsec */
		skb = sock_alloc_send_skb(sk, mtu + LL_RESERVED_SPACE(dev),
					  flags & MSG_DONTWAIT, &err);

		if (skb == NULL) {
			IP6_INC_STATS(Ip6OutDiscards);
			goto out;
		}

		skb->dst = dst_clone(dst);

		skb_reserve(skb, (dev->hard_header_len + 15) & ~15);

		hdr = (struct ipv6hdr *) skb->tail;
		skb->nh.ipv6h = hdr;

		if (!sk->protinfo.af_inet.hdrincl) {
			ip6_bld_1(sk, skb, fl, hlimit,
				  jumbolen ? sizeof(struct ipv6hdr) : pktlength);

			if (opt || jumbolen) {
				u8 *prev_hdr = &hdr->nexthdr;
				prev_hdr = ipv6_build_nfrag_opts(skb, prev_hdr, opt, final_dst, jumbolen);
				if (opt && opt->opt_flen)
					ipv6_build_frag_opts(skb, prev_hdr, opt);
			}
		}

		skb_put(skb, length);
		err = getfrag(data, &hdr->saddr,
			      ((char *) hdr) + (pktlength - length),
			      0, length);
		if (!opt || !opt->dst1opt)
			skb->h.raw = ((char *) hdr) + (pktlength - length);

		if (!err) {
			IP6_INC_STATS(Ip6OutRequests);
			err = NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL, dst->dev, ip6_maybe_reroute);
		} else {
			err = -EFAULT;
			kfree_skb(skb);
		}
	} else {
		if (sk->protinfo.af_inet.hdrincl || jumbolen ||
		    np->pmtudisc == IPV6_PMTUDISC_DO) {
			ipv6_local_error(sk, EMSGSIZE, fl, mtu);
			err = -EMSGSIZE;
			goto out;
		}

		err = ip6_frag_xmit(sk, getfrag, data, dst, fl, opt, final_dst, hlimit,
				    flags, length, mtu);
	}

	/*
	 *	cleanup
	 */
out:
	ip6_dst_store(sk, dst,
		      !ipv6_addr_cmp(&fl->fl6_dst, &np->daddr) ?
		      &np->daddr : NULL);
	if (err > 0)
		err = np->recverr ? net_xmit_errno(err) : 0;
	return err;
}
/* Send RST reply */
static void send_reset(struct sk_buff *oldskb)
{
	struct sk_buff *nskb;
	struct tcphdr otcph, *tcph;
	unsigned int otcplen, hh_len;
	int tcphoff, needs_ack;
	const struct ipv6hdr *oip6h = oldskb->nh.ipv6h;
	struct ipv6hdr *ip6h;
	struct dst_entry *dst = NULL;
	u8 proto;
	struct flowi fl;

	if ((!(ipv6_addr_type(&oip6h->saddr) & IPV6_ADDR_UNICAST)) ||
	    (!(ipv6_addr_type(&oip6h->daddr) & IPV6_ADDR_UNICAST))) {
		DEBUGP("ip6t_REJECT: addr is not unicast.\n");
		return;
	}

	proto = oip6h->nexthdr;
	tcphoff = ipv6_skip_exthdr(oldskb, ((u8*)(oip6h+1) - oldskb->data), &proto);

	if ((tcphoff < 0) || (tcphoff > oldskb->len)) {
		DEBUGP("ip6t_REJECT: Can't get TCP header.\n");
		return;
	}

	otcplen = oldskb->len - tcphoff;

	/* IP header checks: fragment, too short. */
	if ((proto != IPPROTO_TCP) || (otcplen < sizeof(struct tcphdr))) {
		DEBUGP("ip6t_REJECT: proto(%d) != IPPROTO_TCP, or too short. otcplen = %d\n",
			proto, otcplen);
		return;
	}

	if (skb_copy_bits(oldskb, tcphoff, &otcph, sizeof(struct tcphdr)))
		BUG();

	/* No RST for RST. */
	if (otcph.rst) {
		DEBUGP("ip6t_REJECT: RST is set\n");
		return;
	}

	/* Check checksum. */
	if (csum_ipv6_magic(&oip6h->saddr, &oip6h->daddr, otcplen, IPPROTO_TCP,
			    skb_checksum(oldskb, tcphoff, otcplen, 0))) {
		DEBUGP("ip6t_REJECT: TCP checksum is invalid\n");
		return;
	}

	memset(&fl, 0, sizeof(fl));
	fl.proto = IPPROTO_TCP;
	ipv6_addr_copy(&fl.fl6_src, &oip6h->daddr);
	ipv6_addr_copy(&fl.fl6_dst, &oip6h->saddr);
	fl.fl_ip_sport = otcph.dest;
	fl.fl_ip_dport = otcph.source;
	security_skb_classify_flow(oldskb, &fl);
	dst = ip6_route_output(NULL, &fl);
	if (dst == NULL)
		return;
	if (dst->error || xfrm_lookup(&dst, &fl, NULL, 0))
		return;

	hh_len = (dst->dev->hard_header_len + 15)&~15;
	nskb = alloc_skb(hh_len + 15 + dst->header_len + sizeof(struct ipv6hdr)
			 + sizeof(struct tcphdr) + dst->trailer_len,
			 GFP_ATOMIC);

	if (!nskb) {
		if (net_ratelimit())
			printk("ip6t_REJECT: Can't alloc skb\n");
		dst_release(dst);
		return;
	}

	nskb->dst = dst;

	skb_reserve(nskb, hh_len + dst->header_len);

	ip6h = nskb->nh.ipv6h = (struct ipv6hdr *)
					skb_put(nskb, sizeof(struct ipv6hdr));
	ip6h->version = 6;
	ip6h->hop_limit = dst_metric(dst, RTAX_HOPLIMIT);
	ip6h->nexthdr = IPPROTO_TCP;
	ip6h->payload_len = htons(sizeof(struct tcphdr));
	ipv6_addr_copy(&ip6h->saddr, &oip6h->daddr);
	ipv6_addr_copy(&ip6h->daddr, &oip6h->saddr);

	tcph = (struct tcphdr *)skb_put(nskb, sizeof(struct tcphdr));
	/* Truncate to length (no data) */
	tcph->doff = sizeof(struct tcphdr)/4;
	tcph->source = otcph.dest;
	tcph->dest = otcph.source;

	if (otcph.ack) {
		needs_ack = 0;
		tcph->seq = otcph.ack_seq;
		tcph->ack_seq = 0;
	} else {
		needs_ack = 1;
		tcph->ack_seq = htonl(ntohl(otcph.seq) + otcph.syn + otcph.fin
				      + otcplen - (otcph.doff<<2));
		tcph->seq = 0;
	}

	/* Reset flags */
	((u_int8_t *)tcph)[13] = 0;
	tcph->rst = 1;
	tcph->ack = needs_ack;
	tcph->window = 0;
	tcph->urg_ptr = 0;
	tcph->check = 0;

	/* Adjust TCP checksum */
	tcph->check = csum_ipv6_magic(&nskb->nh.ipv6h->saddr,
				      &nskb->nh.ipv6h->daddr,
				      sizeof(struct tcphdr), IPPROTO_TCP,
				      csum_partial(tcph,
						   sizeof(struct tcphdr), 0));

	nf_ct_attach(nskb, oldskb);

	NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, nskb, NULL, nskb->dst->dev,
		dst_output);
}
Esempio n. 10
0
static netdev_tx_t vti_xmit(struct sk_buff *skb, struct net_device *dev,
			    struct flowi *fl)
{
	struct ip_tunnel *tunnel = netdev_priv(dev);
	struct ip_tunnel_parm *parms = &tunnel->parms;
	struct dst_entry *dst = skb_dst(skb);
	struct net_device *tdev;	/* Device to other host */
	int pkt_len = skb->len;
	int err;
	int mtu;

	if (!dst) {
		dev->stats.tx_carrier_errors++;
		goto tx_error_icmp;
	}

	dst_hold(dst);
	dst = xfrm_lookup(tunnel->net, dst, fl, NULL, 0);
	if (IS_ERR(dst)) {
		dev->stats.tx_carrier_errors++;
		goto tx_error_icmp;
	}

	if (!vti_state_check(dst->xfrm, parms->iph.daddr, parms->iph.saddr)) {
		dev->stats.tx_carrier_errors++;
		dst_release(dst);
		goto tx_error_icmp;
	}

	tdev = dst->dev;

	if (tdev == dev) {
		dst_release(dst);
		dev->stats.collisions++;
		goto tx_error;
	}

	mtu = dst_mtu(dst);
	if (skb->len > mtu) {
		skb_dst_update_pmtu(skb, mtu);
		if (skb->protocol == htons(ETH_P_IP)) {
			icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
				  htonl(mtu));
		} else {
			if (mtu < IPV6_MIN_MTU)
				mtu = IPV6_MIN_MTU;

			icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
		}

		dst_release(dst);
		goto tx_error;
	}

	skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(dev)));
	skb_dst_set(skb, dst);
	skb->dev = skb_dst(skb)->dev;

	err = dst_output(tunnel->net, skb->sk, skb);
	if (net_xmit_eval(err) == 0)
		err = pkt_len;
	iptunnel_xmit_stats(dev, err);
	return NETDEV_TX_OK;

tx_error_icmp:
	dst_link_failure(skb);
tx_error:
	dev->stats.tx_errors++;
	kfree_skb(skb);
	return NETDEV_TX_OK;
}
Esempio n. 11
0
int ip6_dst_lookup(struct sock *sk, struct dst_entry **dst, struct flowi *fl)
{
	int err = 0;

	if (sk) {
		struct ipv6_pinfo *np = inet6_sk(sk);
	
		*dst = __sk_dst_check(sk, np->dst_cookie);
		if (*dst) {
			struct rt6_info *rt = (struct rt6_info*)*dst;
	
				/* Yes, checking route validity in not connected
				   case is not very simple. Take into account,
				   that we do not support routing by source, TOS,
				   and MSG_DONTROUTE 		--ANK (980726)
	
				   1. If route was host route, check that
				      cached destination is current.
				      If it is network route, we still may
				      check its validity using saved pointer
				      to the last used address: daddr_cache.
				      We do not want to save whole address now,
				      (because main consumer of this service
				       is tcp, which has not this problem),
				      so that the last trick works only on connected
				      sockets.
				   2. oif also should be the same.
				 */
	
			if (((rt->rt6i_dst.plen != 128 ||
			      ipv6_addr_cmp(&fl->fl6_dst, &rt->rt6i_dst.addr))
			     && (np->daddr_cache == NULL ||
				 ipv6_addr_cmp(&fl->fl6_dst, np->daddr_cache)))
			    || (fl->oif && fl->oif != (*dst)->dev->ifindex)) {
				*dst = NULL;
			} else
				dst_hold(*dst);
		}
	}

	if (*dst == NULL)
		*dst = ip6_route_output(sk, fl);

	if ((err = (*dst)->error))
		goto out_err_release;

	if (ipv6_addr_any(&fl->fl6_src)) {
		err = ipv6_get_saddr(*dst, &fl->fl6_dst, &fl->fl6_src);

		if (err) {
#if IP6_DEBUG >= 2
			printk(KERN_DEBUG "ip6_dst_lookup: "
			       "no availiable source address\n");
#endif
			goto out_err_release;
		}
	}
	if ((err = xfrm_lookup(dst, fl, sk, 0)) < 0) {
		err = -ENETUNREACH;
		goto out_err_release;
        }

	return 0;

out_err_release:
	dst_release(*dst);
	*dst = NULL;
	return err;
}
Esempio n. 12
0
void nf_send_reset6(struct net *net, struct sk_buff *oldskb, int hook)
{
	struct sk_buff *nskb;
	struct tcphdr _otcph;
	const struct tcphdr *otcph;
	unsigned int otcplen, hh_len;
	const struct ipv6hdr *oip6h = ipv6_hdr(oldskb);
	struct ipv6hdr *ip6h;
	struct dst_entry *dst = NULL;
	struct flowi6 fl6;

	if ((!(ipv6_addr_type(&oip6h->saddr) & IPV6_ADDR_UNICAST)) ||
	    (!(ipv6_addr_type(&oip6h->daddr) & IPV6_ADDR_UNICAST))) {
		pr_debug("addr is not unicast.\n");
		return;
	}

	otcph = nf_reject_ip6_tcphdr_get(oldskb, &_otcph, &otcplen, hook);
	if (!otcph)
		return;

	memset(&fl6, 0, sizeof(fl6));
	fl6.flowi6_proto = IPPROTO_TCP;
	fl6.saddr = oip6h->daddr;
	fl6.daddr = oip6h->saddr;
	fl6.fl6_sport = otcph->dest;
	fl6.fl6_dport = otcph->source;
	security_skb_classify_flow(oldskb, flowi6_to_flowi(&fl6));
	dst = ip6_route_output(net, NULL, &fl6);
	if (dst == NULL || dst->error) {
		dst_release(dst);
		return;
	}
	dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), NULL, 0);
	if (IS_ERR(dst))
		return;

	hh_len = (dst->dev->hard_header_len + 15)&~15;
	nskb = alloc_skb(hh_len + 15 + dst->header_len + sizeof(struct ipv6hdr)
			 + sizeof(struct tcphdr) + dst->trailer_len,
			 GFP_ATOMIC);

	if (!nskb) {
		net_dbg_ratelimited("cannot alloc skb\n");
		dst_release(dst);
		return;
	}

	skb_dst_set(nskb, dst);

	skb_reserve(nskb, hh_len + dst->header_len);
	ip6h = nf_reject_ip6hdr_put(nskb, oldskb, IPPROTO_TCP,
				    ip6_dst_hoplimit(dst));
	nf_reject_ip6_tcphdr_put(nskb, oldskb, otcph, otcplen);

	nf_ct_attach(nskb, oldskb);

#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
	/* If we use ip6_local_out for bridged traffic, the MAC source on
	 * the RST will be ours, instead of the destination's.  This confuses
	 * some routers/firewalls, and they drop the packet.  So we need to
	 * build the eth header using the original destination's MAC as the
	 * source, and send the RST packet directly.
	 */
	if (oldskb->nf_bridge) {
		struct ethhdr *oeth = eth_hdr(oldskb);

		nskb->dev = nf_bridge_get_physindev(oldskb);
		nskb->protocol = htons(ETH_P_IPV6);
		ip6h->payload_len = htons(sizeof(struct tcphdr));
		if (dev_hard_header(nskb, nskb->dev, ntohs(nskb->protocol),
				    oeth->h_source, oeth->h_dest, nskb->len) < 0)
			return;
		dev_queue_xmit(nskb);
	} else
#endif
		ip6_local_out(net, nskb->sk, nskb);
}
Esempio n. 13
0
int ip6_route_me_harder(struct sk_buff *skb)
{
	struct net *net = dev_net(skb_dst(skb)->dev);
	const struct ipv6hdr *iph = ipv6_hdr(skb);
	unsigned int hh_len;
	struct dst_entry *dst;
	struct flowi6 fl6 = {
		.flowi6_oif = skb->sk ? skb->sk->sk_bound_dev_if : 0,
		.flowi6_mark = skb->mark,
		.daddr = iph->daddr,
		.saddr = iph->saddr,
	};

	dst = ip6_route_output(net, skb->sk, &fl6);
	if (dst->error) {
		IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES);
		LIMIT_NETDEBUG(KERN_DEBUG "ip6_route_me_harder: No more route.\n");
		dst_release(dst);
		return -EINVAL;
	}

	/* Drop old route. */
	skb_dst_drop(skb);

	skb_dst_set(skb, dst);

#ifdef CONFIG_XFRM
	if (!(IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) &&
	    xfrm_decode_session(skb, flowi6_to_flowi(&fl6), AF_INET6) == 0) {
		skb_dst_set(skb, NULL);
		dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), skb->sk, 0);
		if (IS_ERR(dst))
			return -1;
		skb_dst_set(skb, dst);
	}
#endif

	/* Change in oif may mean change in hh_len. */
	hh_len = skb_dst(skb)->dev->hard_header_len;
	if (skb_headroom(skb) < hh_len &&
	    pskb_expand_head(skb, HH_DATA_ALIGN(hh_len - skb_headroom(skb)),
			     0, GFP_ATOMIC))
		return -1;

	return 0;
}
EXPORT_SYMBOL(ip6_route_me_harder);

/*
 * Extra routing may needed on local out, as the QUEUE target never
 * returns control to the table.
 */

struct ip6_rt_info {
	struct in6_addr daddr;
	struct in6_addr saddr;
	u_int32_t mark;
};

static void nf_ip6_saveroute(const struct sk_buff *skb,
			     struct nf_queue_entry *entry)
{
	struct ip6_rt_info *rt_info = nf_queue_entry_reroute(entry);

	if (entry->hook == NF_INET_LOCAL_OUT) {
		const struct ipv6hdr *iph = ipv6_hdr(skb);

		rt_info->daddr = iph->daddr;
		rt_info->saddr = iph->saddr;
		rt_info->mark = skb->mark;
	}
}

static int nf_ip6_reroute(struct sk_buff *skb,
			  const struct nf_queue_entry *entry)
{
	struct ip6_rt_info *rt_info = nf_queue_entry_reroute(entry);

	if (entry->hook == NF_INET_LOCAL_OUT) {
		const struct ipv6hdr *iph = ipv6_hdr(skb);
		if (!ipv6_addr_equal(&iph->daddr, &rt_info->daddr) ||
		    !ipv6_addr_equal(&iph->saddr, &rt_info->saddr) ||
		    skb->mark != rt_info->mark)
			return ip6_route_me_harder(skb);
	}
	return 0;
}

static int nf_ip6_route(struct net *net, struct dst_entry **dst,
			struct flowi *fl, bool strict)
{
	static const struct ipv6_pinfo fake_pinfo;
	static const struct inet_sock fake_sk = {
		/* makes ip6_route_output set RT6_LOOKUP_F_IFACE: */
		.sk.sk_bound_dev_if = 1,
		.pinet6 = (struct ipv6_pinfo *) &fake_pinfo,
	};
	const void *sk = strict ? &fake_sk : NULL;
	struct dst_entry *result;
	int err;

	result = ip6_route_output(net, sk, &fl->u.ip6);
	err = result->error;
	if (err)
		dst_release(result);
	else
		*dst = result;
	return err;
}

__sum16 nf_ip6_checksum(struct sk_buff *skb, unsigned int hook,
			     unsigned int dataoff, u_int8_t protocol)
{
	const struct ipv6hdr *ip6h = ipv6_hdr(skb);
	__sum16 csum = 0;

	switch (skb->ip_summed) {
	case CHECKSUM_COMPLETE:
		if (hook != NF_INET_PRE_ROUTING && hook != NF_INET_LOCAL_IN)
			break;
		if (!csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
				     skb->len - dataoff, protocol,
				     csum_sub(skb->csum,
					      skb_checksum(skb, 0,
							   dataoff, 0)))) {
			skb->ip_summed = CHECKSUM_UNNECESSARY;
			break;
		}
		/* fall through */
	case CHECKSUM_NONE:
		skb->csum = ~csum_unfold(
				csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
					     skb->len - dataoff,
					     protocol,
					     csum_sub(0,
						      skb_checksum(skb, 0,
								   dataoff, 0))));
		csum = __skb_checksum_complete(skb);
	}
	return csum;
}
EXPORT_SYMBOL(nf_ip6_checksum);

static __sum16 nf_ip6_checksum_partial(struct sk_buff *skb, unsigned int hook,
				       unsigned int dataoff, unsigned int len,
				       u_int8_t protocol)
{
	const struct ipv6hdr *ip6h = ipv6_hdr(skb);
	__wsum hsum;
	__sum16 csum = 0;

	switch (skb->ip_summed) {
	case CHECKSUM_COMPLETE:
		if (len == skb->len - dataoff)
			return nf_ip6_checksum(skb, hook, dataoff, protocol);
		/* fall through */
	case CHECKSUM_NONE:
		hsum = skb_checksum(skb, 0, dataoff, 0);
		skb->csum = ~csum_unfold(csum_ipv6_magic(&ip6h->saddr,
							 &ip6h->daddr,
							 skb->len - dataoff,
							 protocol,
							 csum_sub(0, hsum)));
		skb->ip_summed = CHECKSUM_NONE;
		return __skb_checksum_complete_head(skb, dataoff + len);
	}
	return csum;
};

static const struct nf_afinfo nf_ip6_afinfo = {
	.family			= AF_INET6,
	.checksum		= nf_ip6_checksum,
	.checksum_partial	= nf_ip6_checksum_partial,
	.route			= nf_ip6_route,
	.saveroute		= nf_ip6_saveroute,
	.reroute		= nf_ip6_reroute,
	.route_key_size		= sizeof(struct ip6_rt_info),
};

int __init ipv6_netfilter_init(void)
{
	return nf_register_afinfo(&nf_ip6_afinfo);
}

/* This can be called from inet6_init() on errors, so it cannot
 * be marked __exit. -DaveM
 */
void ipv6_netfilter_fini(void)
{
	nf_unregister_afinfo(&nf_ip6_afinfo);
}
Esempio n. 14
0
/* Reroute packet to local IPv4 stack after DNAT */
static int
__ip_vs_reroute_locally(struct sk_buff *skb)
{
	struct rtable *rt = skb_rtable(skb);
	struct net_device *dev = rt->dst.dev;
	struct net *net = dev_net(dev);
	struct iphdr *iph = ip_hdr(skb);

	if (rt_is_input_route(rt)) {
		unsigned long orefdst = skb->_skb_refdst;

		if (ip_route_input(skb, iph->daddr, iph->saddr,
				   iph->tos, skb->dev))
			return 0;
		refdst_drop(orefdst);
	} else {
		struct flowi4 fl4 = {
			.daddr = iph->daddr,
			.saddr = iph->saddr,
			.flowi4_tos = RT_TOS(iph->tos),
			.flowi4_mark = skb->mark,
		};

		rt = ip_route_output_key(net, &fl4);
		if (IS_ERR(rt))
			return 0;
		if (!(rt->rt_flags & RTCF_LOCAL)) {
			ip_rt_put(rt);
			return 0;
		}
		/* Drop old route. */
		skb_dst_drop(skb);
		skb_dst_set(skb, &rt->dst);
	}
	return 1;
}

#ifdef CONFIG_IP_VS_IPV6

static inline int __ip_vs_is_local_route6(struct rt6_info *rt)
{
	return rt->dst.dev && rt->dst.dev->flags & IFF_LOOPBACK;
}

static struct dst_entry *
__ip_vs_route_output_v6(struct net *net, struct in6_addr *daddr,
			struct in6_addr *ret_saddr, int do_xfrm)
{
	struct dst_entry *dst;
	struct flowi6 fl6 = {
		.daddr = *daddr,
	};

	dst = ip6_route_output(net, NULL, &fl6);
	if (dst->error)
		goto out_err;
	if (!ret_saddr)
		return dst;
	if (ipv6_addr_any(&fl6.saddr) &&
	    ipv6_dev_get_saddr(net, ip6_dst_idev(dst)->dev,
			       &fl6.daddr, 0, &fl6.saddr) < 0)
		goto out_err;
	if (do_xfrm) {
		dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), NULL, 0);
		if (IS_ERR(dst)) {
			dst = NULL;
			goto out_err;
		}
	}
	*ret_saddr = fl6.saddr;
	return dst;

out_err:
	dst_release(dst);
	IP_VS_DBG_RL("ip6_route_output error, dest: %pI6\n", daddr);
	return NULL;
}

/*
 * Get route to destination or remote server
 */
static struct rt6_info *
__ip_vs_get_out_rt_v6(struct sk_buff *skb, struct ip_vs_dest *dest,
		      struct in6_addr *daddr, struct in6_addr *ret_saddr,
		      int do_xfrm, int rt_mode)
{
	struct net *net = dev_net(skb_dst(skb)->dev);
	struct rt6_info *rt;			/* Route to the other host */
	struct rt6_info *ort;			/* Original route */
	struct dst_entry *dst;
	int local;

	if (dest) {
		spin_lock(&dest->dst_lock);
		rt = (struct rt6_info *)__ip_vs_dst_check(dest, 0);
		if (!rt) {
			u32 cookie;

			dst = __ip_vs_route_output_v6(net, &dest->addr.in6,
						      &dest->dst_saddr.in6,
						      do_xfrm);
			if (!dst) {
				spin_unlock(&dest->dst_lock);
				return NULL;
			}
			rt = (struct rt6_info *) dst;
			cookie = rt->rt6i_node ? rt->rt6i_node->fn_sernum : 0;
			__ip_vs_dst_set(dest, 0, dst_clone(&rt->dst), cookie);
			IP_VS_DBG(10, "new dst %pI6, src %pI6, refcnt=%d\n",
				  &dest->addr.in6, &dest->dst_saddr.in6,
				  atomic_read(&rt->dst.__refcnt));
		}
		if (ret_saddr)
			*ret_saddr = dest->dst_saddr.in6;
		spin_unlock(&dest->dst_lock);
	} else {
		dst = __ip_vs_route_output_v6(net, daddr, ret_saddr, do_xfrm);
		if (!dst)
			return NULL;
		rt = (struct rt6_info *) dst;
	}

	local = __ip_vs_is_local_route6(rt);
	if (!((local ? IP_VS_RT_MODE_LOCAL : IP_VS_RT_MODE_NON_LOCAL) &
	      rt_mode)) {
		IP_VS_DBG_RL("Stopping traffic to %s address, dest: %pI6\n",
			     local ? "local":"non-local", daddr);
		dst_release(&rt->dst);
		return NULL;
	}
	if (local && !(rt_mode & IP_VS_RT_MODE_RDR) &&
	    !((ort = (struct rt6_info *) skb_dst(skb)) &&
	      __ip_vs_is_local_route6(ort))) {
		IP_VS_DBG_RL("Redirect from non-local address %pI6 to local "
			     "requires NAT method, dest: %pI6\n",
			     &ipv6_hdr(skb)->daddr, daddr);
		dst_release(&rt->dst);
		return NULL;
	}
	if (unlikely(!local && (!skb->dev || skb->dev->flags & IFF_LOOPBACK) &&
		     ipv6_addr_type(&ipv6_hdr(skb)->saddr) &
				    IPV6_ADDR_LOOPBACK)) {
		IP_VS_DBG_RL("Stopping traffic from loopback address %pI6 "
			     "to non-local address, dest: %pI6\n",
			     &ipv6_hdr(skb)->saddr, daddr);
		dst_release(&rt->dst);
		return NULL;
	}

	return rt;
}
#endif


/*
 *	Release dest->dst_cache before a dest is removed
 */
void
ip_vs_dst_reset(struct ip_vs_dest *dest)
{
	struct dst_entry *old_dst;

	old_dst = dest->dst_cache;
	dest->dst_cache = NULL;
	dst_release(old_dst);
	dest->dst_saddr.ip = 0;
}

#define IP_VS_XMIT_TUNNEL(skb, cp)				\
({								\
	int __ret = NF_ACCEPT;					\
								\
	(skb)->ipvs_property = 1;				\
	if (unlikely((cp)->flags & IP_VS_CONN_F_NFCT))		\
		__ret = ip_vs_confirm_conntrack(skb);		\
	if (__ret == NF_ACCEPT) {				\
		nf_reset(skb);					\
		skb_forward_csum(skb);				\
	}							\
	__ret;							\
})

#define IP_VS_XMIT_NAT(pf, skb, cp, local)		\
do {							\
	(skb)->ipvs_property = 1;			\
	if (likely(!((cp)->flags & IP_VS_CONN_F_NFCT)))	\
		ip_vs_notrack(skb);			\
	else						\
		ip_vs_update_conntrack(skb, cp, 1);	\
	if (local)					\
		return NF_ACCEPT;			\
	skb_forward_csum(skb);				\
	NF_HOOK(pf, NF_INET_LOCAL_OUT, (skb), NULL,	\
		skb_dst(skb)->dev, dst_output);		\
} while (0)

#define IP_VS_XMIT(pf, skb, cp, local)			\
do {							\
	(skb)->ipvs_property = 1;			\
	if (likely(!((cp)->flags & IP_VS_CONN_F_NFCT)))	\
		ip_vs_notrack(skb);			\
	if (local)					\
		return NF_ACCEPT;			\
	skb_forward_csum(skb);				\
	NF_HOOK(pf, NF_INET_LOCAL_OUT, (skb), NULL,	\
		skb_dst(skb)->dev, dst_output);		\
} while (0)


/*
 *      NULL transmitter (do nothing except return NF_ACCEPT)
 */
int
ip_vs_null_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
		struct ip_vs_protocol *pp)
{
	/* we do not touch skb and do not need pskb ptr */
	IP_VS_XMIT(NFPROTO_IPV4, skb, cp, 1);
}
Esempio n. 15
0
/* Send RST reply */
static void send_reset(struct net *net, struct sk_buff *oldskb)
{
	struct sk_buff *nskb;
	struct tcphdr otcph, *tcph;
	unsigned int otcplen, hh_len;
	int tcphoff, needs_ack;
	const struct ipv6hdr *oip6h = ipv6_hdr(oldskb);
	struct ipv6hdr *ip6h;
#define DEFAULT_TOS_VALUE	0x0U
	const __u8 tclass = DEFAULT_TOS_VALUE;
	struct dst_entry *dst = NULL;
	u8 proto;
	__be16 frag_off;
	struct flowi6 fl6;

	if ((!(ipv6_addr_type(&oip6h->saddr) & IPV6_ADDR_UNICAST)) ||
	    (!(ipv6_addr_type(&oip6h->daddr) & IPV6_ADDR_UNICAST))) {
		pr_debug("addr is not unicast.\n");
		return;
	}

	proto = oip6h->nexthdr;
	tcphoff = ipv6_skip_exthdr(oldskb, ((u8*)(oip6h+1) - oldskb->data), &proto, &frag_off);

	if ((tcphoff < 0) || (tcphoff > oldskb->len)) {
		pr_debug("Cannot get TCP header.\n");
		return;
	}

	otcplen = oldskb->len - tcphoff;

	/* IP header checks: fragment, too short. */
	if (proto != IPPROTO_TCP || otcplen < sizeof(struct tcphdr)) {
		pr_debug("proto(%d) != IPPROTO_TCP, "
			 "or too short. otcplen = %d\n",
			 proto, otcplen);
		return;
	}

	if (skb_copy_bits(oldskb, tcphoff, &otcph, sizeof(struct tcphdr)))
		BUG();

	/* No RST for RST. */
	if (otcph.rst) {
		pr_debug("RST is set\n");
		return;
	}

	/* Check checksum. */
	if (csum_ipv6_magic(&oip6h->saddr, &oip6h->daddr, otcplen, IPPROTO_TCP,
			    skb_checksum(oldskb, tcphoff, otcplen, 0))) {
		pr_debug("TCP checksum is invalid\n");
		return;
	}

	memset(&fl6, 0, sizeof(fl6));
	fl6.flowi6_proto = IPPROTO_TCP;
	fl6.saddr = oip6h->daddr;
	fl6.daddr = oip6h->saddr;
	fl6.fl6_sport = otcph.dest;
	fl6.fl6_dport = otcph.source;
	security_skb_classify_flow(oldskb, flowi6_to_flowi(&fl6));
	dst = ip6_route_output(net, NULL, &fl6);
	if (dst == NULL || dst->error) {
		dst_release(dst);
		return;
	}
	dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), NULL, 0);
	if (IS_ERR(dst))
		return;

	hh_len = (dst->dev->hard_header_len + 15)&~15;
	nskb = alloc_skb(hh_len + 15 + dst->header_len + sizeof(struct ipv6hdr)
			 + sizeof(struct tcphdr) + dst->trailer_len,
			 GFP_ATOMIC);

	if (!nskb) {
		net_dbg_ratelimited("cannot alloc skb\n");
		dst_release(dst);
		return;
	}

	skb_dst_set(nskb, dst);

	skb_reserve(nskb, hh_len + dst->header_len);

	skb_put(nskb, sizeof(struct ipv6hdr));
	skb_reset_network_header(nskb);
	ip6h = ipv6_hdr(nskb);
	*(__be32 *)ip6h =  htonl(0x60000000 | (tclass << 20));
	ip6h->hop_limit = ip6_dst_hoplimit(dst);
	ip6h->nexthdr = IPPROTO_TCP;
	ip6h->saddr = oip6h->daddr;
	ip6h->daddr = oip6h->saddr;

	skb_reset_transport_header(nskb);
	tcph = (struct tcphdr *)skb_put(nskb, sizeof(struct tcphdr));
	/* Truncate to length (no data) */
	tcph->doff = sizeof(struct tcphdr)/4;
	tcph->source = otcph.dest;
	tcph->dest = otcph.source;

	if (otcph.ack) {
		needs_ack = 0;
		tcph->seq = otcph.ack_seq;
		tcph->ack_seq = 0;
	} else {
		needs_ack = 1;
		tcph->ack_seq = htonl(ntohl(otcph.seq) + otcph.syn + otcph.fin
				      + otcplen - (otcph.doff<<2));
		tcph->seq = 0;
	}

	/* Reset flags */
	((u_int8_t *)tcph)[13] = 0;
	tcph->rst = 1;
	tcph->ack = needs_ack;
	tcph->window = 0;
	tcph->urg_ptr = 0;
	tcph->check = 0;

	/* Adjust TCP checksum */
	tcph->check = csum_ipv6_magic(&ipv6_hdr(nskb)->saddr,
				      &ipv6_hdr(nskb)->daddr,
				      sizeof(struct tcphdr), IPPROTO_TCP,
				      csum_partial(tcph,
						   sizeof(struct tcphdr), 0));

	nf_ct_attach(nskb, oldskb);

	ip6_local_out(nskb);
}
Esempio n. 16
0
File: ip_vti.c Progetto: 7799/linux
static netdev_tx_t vti_xmit(struct sk_buff *skb, struct net_device *dev,
			    struct flowi *fl)
{
	struct ip_tunnel *tunnel = netdev_priv(dev);
	struct ip_tunnel_parm *parms = &tunnel->parms;
	struct dst_entry *dst = skb_dst(skb);
	struct net_device *tdev;	/* Device to other host */
	int err;

	if (!dst) {
		dev->stats.tx_carrier_errors++;
		goto tx_error_icmp;
	}

	dst_hold(dst);
	dst = xfrm_lookup(tunnel->net, dst, fl, NULL, 0);
	if (IS_ERR(dst)) {
		dev->stats.tx_carrier_errors++;
		goto tx_error_icmp;
	}

	if (!vti_state_check(dst->xfrm, parms->iph.daddr, parms->iph.saddr)) {
		dev->stats.tx_carrier_errors++;
		dst_release(dst);
		goto tx_error_icmp;
	}

	tdev = dst->dev;

	if (tdev == dev) {
		dst_release(dst);
		dev->stats.collisions++;
		goto tx_error;
	}

	if (tunnel->err_count > 0) {
		if (time_before(jiffies,
				tunnel->err_time + IPTUNNEL_ERR_TIMEO)) {
			tunnel->err_count--;
			dst_link_failure(skb);
		} else
			tunnel->err_count = 0;
	}

	skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(dev)));
	skb_dst_set(skb, dst);
	skb->dev = skb_dst(skb)->dev;

	err = dst_output(skb);
	if (net_xmit_eval(err) == 0)
		err = skb->len;
	iptunnel_xmit_stats(err, &dev->stats, dev->tstats);
	return NETDEV_TX_OK;

tx_error_icmp:
	dst_link_failure(skb);
tx_error:
	dev->stats.tx_errors++;
	kfree_skb(skb);
	return NETDEV_TX_OK;
}
Esempio n. 17
0
/* route_me_harder function, used by iptable_nat, iptable_mangle + ip_queue */
int ip_route_me_harder(struct sk_buff *skb, unsigned addr_type)
{
	const struct iphdr *iph = ip_hdr(skb);
	struct rtable *rt;
	struct flowi fl = {};
	struct dst_entry *odst;
	unsigned int hh_len;
	unsigned int type;

	type = inet_addr_type(&init_net, iph->saddr);
	if (addr_type == RTN_UNSPEC)
		addr_type = type;

	/* some non-standard hacks like ipt_REJECT.c:send_reset() can cause
	 * packets with foreign saddr to appear on the NF_INET_LOCAL_OUT hook.
	 */
	if (addr_type == RTN_LOCAL) {
		fl.nl_u.ip4_u.daddr = iph->daddr;
		if (type == RTN_LOCAL)
			fl.nl_u.ip4_u.saddr = iph->saddr;
		fl.nl_u.ip4_u.tos = RT_TOS(iph->tos);
		fl.oif = skb->sk ? skb->sk->sk_bound_dev_if : 0;
		fl.mark = skb->mark;
		if (ip_route_output_key(&init_net, &rt, &fl) != 0)
			return -1;

		/* Drop old route. */
		dst_release(skb->dst);
		skb->dst = &rt->u.dst;
	} else {
		/* non-local src, find valid iif to satisfy
		 * rp-filter when calling ip_route_input. */
		fl.nl_u.ip4_u.daddr = iph->saddr;
		if (ip_route_output_key(&init_net, &rt, &fl) != 0)
			return -1;

		odst = skb->dst;
		if (ip_route_input(skb, iph->daddr, iph->saddr,
				   RT_TOS(iph->tos), rt->u.dst.dev) != 0) {
			dst_release(&rt->u.dst);
			return -1;
		}
		dst_release(&rt->u.dst);
		dst_release(odst);
	}

	if (skb->dst->error)
		return -1;

#ifdef CONFIG_XFRM
	if (!(IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) &&
	    xfrm_decode_session(skb, &fl, AF_INET) == 0)
		if (xfrm_lookup(&skb->dst, &fl, skb->sk, 0))
			return -1;
#endif

	/* Change in oif may mean change in hh_len. */
	hh_len = skb->dst->dev->hard_header_len;
	if (skb_headroom(skb) < hh_len &&
	    pskb_expand_head(skb, hh_len - skb_headroom(skb), 0, GFP_ATOMIC))
		return -1;

	return 0;
}
Esempio n. 18
0
static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr, 
			  int addr_len)
{
	struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr;
 	struct inet_sock *inet = inet_sk(sk);
	struct inet_connection_sock *icsk = inet_csk(sk);
	struct ipv6_pinfo *np = inet6_sk(sk);
	struct tcp_sock *tp = tcp_sk(sk);
	struct in6_addr *saddr = NULL, *final_p = NULL, final;
	struct flowi fl;
	struct dst_entry *dst;
	int addr_type;
	int err;

	if (addr_len < SIN6_LEN_RFC2133) 
		return -EINVAL;

	if (usin->sin6_family != AF_INET6) 
		return(-EAFNOSUPPORT);

	memset(&fl, 0, sizeof(fl));

	if (np->sndflow) {
		fl.fl6_flowlabel = usin->sin6_flowinfo&IPV6_FLOWINFO_MASK;
		IP6_ECN_flow_init(fl.fl6_flowlabel);
		if (fl.fl6_flowlabel&IPV6_FLOWLABEL_MASK) {
			struct ip6_flowlabel *flowlabel;
			flowlabel = fl6_sock_lookup(sk, fl.fl6_flowlabel);
			if (flowlabel == NULL)
				return -EINVAL;
			ipv6_addr_copy(&usin->sin6_addr, &flowlabel->dst);
			fl6_sock_release(flowlabel);
		}
	}

	/*
  	 *	connect() to INADDR_ANY means loopback (BSD'ism).
  	 */
  	
  	if(ipv6_addr_any(&usin->sin6_addr))
		usin->sin6_addr.s6_addr[15] = 0x1; 

	addr_type = ipv6_addr_type(&usin->sin6_addr);

	if(addr_type & IPV6_ADDR_MULTICAST)
		return -ENETUNREACH;

	if (addr_type&IPV6_ADDR_LINKLOCAL) {
		if (addr_len >= sizeof(struct sockaddr_in6) &&
		    usin->sin6_scope_id) {
			/* If interface is set while binding, indices
			 * must coincide.
			 */
			if (sk->sk_bound_dev_if &&
			    sk->sk_bound_dev_if != usin->sin6_scope_id)
				return -EINVAL;

			sk->sk_bound_dev_if = usin->sin6_scope_id;
		}

		/* Connect to link-local address requires an interface */
		if (!sk->sk_bound_dev_if)
			return -EINVAL;
	}

	if (tp->rx_opt.ts_recent_stamp &&
	    !ipv6_addr_equal(&np->daddr, &usin->sin6_addr)) {
		tp->rx_opt.ts_recent = 0;
		tp->rx_opt.ts_recent_stamp = 0;
		tp->write_seq = 0;
	}

	ipv6_addr_copy(&np->daddr, &usin->sin6_addr);
	np->flow_label = fl.fl6_flowlabel;

	/*
	 *	TCP over IPv4
	 */

	if (addr_type == IPV6_ADDR_MAPPED) {
		u32 exthdrlen = icsk->icsk_ext_hdr_len;
		struct sockaddr_in sin;

		SOCK_DEBUG(sk, "connect: ipv4 mapped\n");

		if (__ipv6_only_sock(sk))
			return -ENETUNREACH;

		sin.sin_family = AF_INET;
		sin.sin_port = usin->sin6_port;
		sin.sin_addr.s_addr = usin->sin6_addr.s6_addr32[3];

		icsk->icsk_af_ops = &ipv6_mapped;
		sk->sk_backlog_rcv = tcp_v4_do_rcv;

		err = tcp_v4_connect(sk, (struct sockaddr *)&sin, sizeof(sin));

		if (err) {
			icsk->icsk_ext_hdr_len = exthdrlen;
			icsk->icsk_af_ops = &ipv6_specific;
			sk->sk_backlog_rcv = tcp_v6_do_rcv;
			goto failure;
		} else {
			ipv6_addr_set(&np->saddr, 0, 0, htonl(0x0000FFFF),
				      inet->saddr);
			ipv6_addr_set(&np->rcv_saddr, 0, 0, htonl(0x0000FFFF),
				      inet->rcv_saddr);
		}

		return err;
	}

	if (!ipv6_addr_any(&np->rcv_saddr))
		saddr = &np->rcv_saddr;

	fl.proto = IPPROTO_TCP;
	ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
	ipv6_addr_copy(&fl.fl6_src,
		       (saddr ? saddr : &np->saddr));
	fl.oif = sk->sk_bound_dev_if;
	fl.fl_ip_dport = usin->sin6_port;
	fl.fl_ip_sport = inet->sport;

	if (np->opt && np->opt->srcrt) {
		struct rt0_hdr *rt0 = (struct rt0_hdr *)np->opt->srcrt;
		ipv6_addr_copy(&final, &fl.fl6_dst);
		ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
		final_p = &final;
	}

	security_sk_classify_flow(sk, &fl);

	err = ip6_dst_lookup(sk, &dst, &fl);
	if (err)
		goto failure;
	if (final_p)
		ipv6_addr_copy(&fl.fl6_dst, final_p);

	if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0)
		goto failure;

	if (saddr == NULL) {
		saddr = &fl.fl6_src;
		ipv6_addr_copy(&np->rcv_saddr, saddr);
	}

	/* set the source address */
	ipv6_addr_copy(&np->saddr, saddr);
	inet->rcv_saddr = LOOPBACK4_IPV6;

	sk->sk_gso_type = SKB_GSO_TCPV6;
	__ip6_dst_store(sk, dst, NULL, NULL);

	icsk->icsk_ext_hdr_len = 0;
	if (np->opt)
		icsk->icsk_ext_hdr_len = (np->opt->opt_flen +
					  np->opt->opt_nflen);

	tp->rx_opt.mss_clamp = IPV6_MIN_MTU - sizeof(struct tcphdr) - sizeof(struct ipv6hdr);

	inet->dport = usin->sin6_port;

	tcp_set_state(sk, TCP_SYN_SENT);
	err = inet6_hash_connect(&tcp_death_row, sk);
	if (err)
		goto late_failure;

	if (!tp->write_seq)
		tp->write_seq = secure_tcpv6_sequence_number(np->saddr.s6_addr32,
							     np->daddr.s6_addr32,
							     inet->sport,
							     inet->dport);

	err = tcp_connect(sk);
	if (err)
		goto late_failure;

	return 0;

late_failure:
	tcp_set_state(sk, TCP_CLOSE);
	__sk_dst_reset(sk);
failure:
	inet->dport = 0;
	sk->sk_route_caps = 0;
	return err;
}