Example #1
0
static struct sock *dccp_v6_hnd_req(struct sock *sk,struct sk_buff *skb)
{
	const struct dccp_hdr *dh = dccp_hdr(skb);
	const struct ipv6hdr *iph = ipv6_hdr(skb);
	struct sock *nsk;
	struct request_sock **prev;
	/* Find possible connection requests. */
	struct request_sock *req = inet6_csk_search_req(sk, &prev,
							dh->dccph_sport,
							&iph->saddr,
							&iph->daddr,
							inet6_iif(skb));
	if (req != NULL)
		return dccp_check_req(sk, skb, req, prev);

	nsk = __inet6_lookup_established(sock_net(sk), &dccp_hashinfo,
					 &iph->saddr, dh->dccph_sport,
					 &iph->daddr, ntohs(dh->dccph_dport),
					 inet6_iif(skb));
	if (nsk != NULL) {
		if (nsk->sk_state != DCCP_TIME_WAIT) {
			bh_lock_sock(nsk);
			return nsk;
		}
		inet_twsk_put(inet_twsk(nsk));
		return NULL;
	}

	return sk;
}
Example #2
0
static void dccp_v6_ctl_send_reset(struct sock *sk, struct sk_buff *rxskb)
{
	struct ipv6hdr *rxip6h;
	struct sk_buff *skb;
	struct flowi fl;
	struct net *net = dev_net(skb_dst(rxskb)->dev);
	struct sock *ctl_sk = net->dccp.v6_ctl_sk;
	struct dst_entry *dst;

	if (dccp_hdr(rxskb)->dccph_type == DCCP_PKT_RESET)
		return;

	if (!ipv6_unicast_destination(rxskb))
		return;

	skb = dccp_ctl_make_reset(ctl_sk, rxskb);
	if (skb == NULL)
		return;

	rxip6h = ipv6_hdr(rxskb);
	dccp_hdr(skb)->dccph_checksum = dccp_v6_csum_finish(skb, &rxip6h->saddr,
							    &rxip6h->daddr);

	memset(&fl, 0, sizeof(fl));
	ipv6_addr_copy(&fl.fl6_dst, &rxip6h->saddr);
	ipv6_addr_copy(&fl.fl6_src, &rxip6h->daddr);

	fl.proto = IPPROTO_DCCP;
	fl.oif = inet6_iif(rxskb);
	fl.fl_ip_dport = dccp_hdr(skb)->dccph_dport;
	fl.fl_ip_sport = dccp_hdr(skb)->dccph_sport;
	security_skb_classify_flow(rxskb, &fl);

	/* sk = NULL, but it is safe for now. RST socket required. */
	if (!ip6_dst_lookup(ctl_sk, &dst, &fl)) {
		if (xfrm_lookup(net, &dst, &fl, NULL, 0) >= 0) {
			skb_dst_set(skb, dst);
			ip6_xmit(ctl_sk, skb, &fl, NULL, 0);
			DCCP_INC_STATS_BH(DCCP_MIB_OUTSEGS);
			DCCP_INC_STATS_BH(DCCP_MIB_OUTRSTS);
			return;
		}
	}

	kfree_skb(skb);
}
Example #3
0
static void dccp_v6_ctl_send_reset(struct sock *sk, struct sk_buff *rxskb)
{
	const struct ipv6hdr *rxip6h;
	struct sk_buff *skb;
	struct flowi6 fl6;
	struct net *net = dev_net(skb_dst(rxskb)->dev);
	struct sock *ctl_sk = net->dccp.v6_ctl_sk;
	struct dst_entry *dst;

	if (dccp_hdr(rxskb)->dccph_type == DCCP_PKT_RESET)
		return;

	if (!ipv6_unicast_destination(rxskb))
		return;

	skb = dccp_ctl_make_reset(ctl_sk, rxskb);
	if (skb == NULL)
		return;

	rxip6h = ipv6_hdr(rxskb);
	dccp_hdr(skb)->dccph_checksum = dccp_v6_csum_finish(skb, &rxip6h->saddr,
							    &rxip6h->daddr);

	memset(&fl6, 0, sizeof(fl6));
	fl6.daddr = rxip6h->saddr;
	fl6.saddr = rxip6h->daddr;

	fl6.flowi6_proto = IPPROTO_DCCP;
	fl6.flowi6_oif = inet6_iif(rxskb);
	fl6.fl6_dport = dccp_hdr(skb)->dccph_dport;
	fl6.fl6_sport = dccp_hdr(skb)->dccph_sport;
	security_skb_classify_flow(rxskb, flowi6_to_flowi(&fl6));

	/* sk = NULL, but it is safe for now. RST socket required. */
	dst = ip6_dst_lookup_flow(ctl_sk, &fl6, NULL, false);
	if (!IS_ERR(dst)) {
		skb_dst_set(skb, dst);
		ip6_xmit(ctl_sk, skb, &fl6, NULL, 0);
		DCCP_INC_STATS_BH(DCCP_MIB_OUTSEGS);
		DCCP_INC_STATS_BH(DCCP_MIB_OUTRSTS);
		return;
	}

	kfree_skb(skb);
}
Example #4
0
static void tcp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
		u8 type, u8 code, int offset, __be32 info)
{
	const struct ipv6hdr *hdr = (const 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;
	struct net *net = dev_net(skb->dev);

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

	if (sk == NULL) {
		ICMP6_INC_STATS_BH(net, __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(net, LINUX_MIB_LOCKDROPPEDICMPS);

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

	if (ipv6_hdr(skb)->hop_limit < inet6_sk(sk)->min_hopcount) {
		NET_INC_STATS_BH(net, LINUX_MIB_TCPMINTTLDROP);
		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(net, LINUX_MIB_OUTOFWINDOWICMPS);
		goto out;
	}

	np = inet6_sk(sk);

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

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

		
		dst = __sk_dst_check(sk, np->dst_cookie);

		if (dst == NULL) {
			struct inet_sock *inet = inet_sk(sk);
			struct flowi6 fl6;

			memset(&fl6, 0, sizeof(fl6));
			fl6.flowi6_proto = IPPROTO_TCP;
			fl6.daddr = np->daddr;
			fl6.saddr = np->saddr;
			fl6.flowi6_oif = sk->sk_bound_dev_if;
			fl6.flowi6_mark = sk->sk_mark;
			fl6.fl6_dport = inet->inet_dport;
			fl6.fl6_sport = inet->inet_sport;
			fl6.flowi6_uid = sock_i_uid(sk);
			security_skb_classify_flow(skb, flowi6_to_flowi(&fl6));

			dst = ip6_dst_lookup_flow(sk, &fl6, NULL, false);
			if (IS_ERR(dst)) {
				sk->sk_err_soft = -PTR_ERR(dst);
				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);
		} 
		dst_release(dst);
		goto out;
	}

	icmpv6_err_convert(type, code, &err);

	
	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;

		WARN_ON(req->sk != NULL);

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

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

	case TCP_SYN_SENT:
	case TCP_SYN_RECV:  
		if (!sock_owned_by_user(sk)) {
			sk->sk_err = err;
			sk->sk_error_report(sk);		

			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);
}
Example #5
0
static void dccp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
			u8 type, u8 code, int offset, __be32 info)
{
	const struct ipv6hdr *hdr = (const 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 == NDISC_REDIRECT) {
		struct dst_entry *dst = __sk_dst_check(sk, np->dst_cookie);

		if (dst)
			dst->ops->redirect(dst, sk, skb);
		goto out;
	}

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

		if (!ip6_sk_accept_pmtu(sk))
			goto out;

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

		dst = inet6_csk_update_pmtu(sk, ntohl(info));
		if (!dst)
			goto out;

		if (inet_csk(sk)->icsk_pmtu_cookie > dst_mtu(dst))
			dccp_sync_mss(sk, dst_mtu(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 (!between48(seq, dccp_rsk(req)->dreq_iss,
				    dccp_rsk(req)->dreq_gss)) {
			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);
}
Example #6
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 inet_request_sock *ireq = inet_rsk(req);
	struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
	struct inet_sock *newinet;
	struct dccp6_sock *newdp6;
	struct sock *newsk;

	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;
		newinet = inet_sk(newsk);
		newinet->pinet6 = &newdp6->inet6;
		newnp = inet6_sk(newsk);

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

		ipv6_addr_set_v4mapped(newinet->inet_daddr, &newsk->sk_v6_daddr);

		ipv6_addr_set_v4mapped(newinet->inet_saddr, &newnp->saddr);

		newsk->sk_v6_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;
	}


	if (sk_acceptq_is_full(sk))
		goto out_overflow;

	if (dst == NULL) {
		struct in6_addr *final_p, final;
		struct flowi6 fl6;

		memset(&fl6, 0, sizeof(fl6));
		fl6.flowi6_proto = IPPROTO_DCCP;
		fl6.daddr = ireq->ir_v6_rmt_addr;
		final_p = fl6_update_dst(&fl6, np->opt, &final);
		fl6.saddr = ireq->ir_v6_loc_addr;
		fl6.flowi6_oif = sk->sk_bound_dev_if;
		fl6.fl6_dport = ireq->ir_rmt_port;
		fl6.fl6_sport = htons(ireq->ir_num);
		security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));

		dst = ip6_dst_lookup_flow(sk, &fl6, final_p, false);
		if (IS_ERR(dst))
			goto out;
	}

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

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

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

	newsk->sk_v6_daddr	= ireq->ir_v6_rmt_addr;
	newnp->saddr		= ireq->ir_v6_loc_addr;
	newsk->sk_v6_rcv_saddr	= ireq->ir_v6_loc_addr;
	newsk->sk_bound_dev_if	= ireq->ir_iif;

	/* Now IPv6 options...

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

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

	/* Clone pktoptions received with SYN */
	newnp->pktoptions = NULL;
	if (ireq->pktopts != NULL) {
		newnp->pktoptions = skb_clone(ireq->pktopts, GFP_ATOMIC);
		consume_skb(ireq->pktopts);
		ireq->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 (np->opt != NULL)
		newnp->opt = ipv6_dup_options(newsk, np->opt);

	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->inet_daddr = newinet->inet_saddr = LOOPBACK4_IPV6;
	newinet->inet_rcv_saddr = LOOPBACK4_IPV6;

	if (__inet_inherit_port(sk, newsk) < 0) {
		inet_csk_prepare_forced_close(newsk);
		dccp_done(newsk);
		goto out;
	}
	__inet6_hash(newsk, NULL);

	return newsk;

out_overflow:
	NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS);
out_nonewsk:
	dst_release(dst);
out:
	NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS);
	return NULL;
}
Example #7
0
static int dccp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
{
	struct request_sock *req;
	struct dccp_request_sock *dreq;
	struct inet_request_sock *ireq;
	struct ipv6_pinfo *np = inet6_sk(sk);
	const __be32 service = dccp_hdr_request(skb)->dccph_req_service;
	struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb);

	if (skb->protocol == htons(ETH_P_IP))
		return dccp_v4_conn_request(sk, skb);

	if (!ipv6_unicast_destination(skb))
		return 0;	/* discard, don't send a reset here */

	if (dccp_bad_service_code(sk, service)) {
		dcb->dccpd_reset_code = DCCP_RESET_CODE_BAD_SERVICE_CODE;
		goto drop;
	}
	/*
	 * There are no SYN attacks on IPv6, yet...
	 */
	dcb->dccpd_reset_code = DCCP_RESET_CODE_TOO_BUSY;
	if (inet_csk_reqsk_queue_is_full(sk))
		goto drop;

	if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1)
		goto drop;

	req = inet6_reqsk_alloc(&dccp6_request_sock_ops);
	if (req == NULL)
		goto drop;

	if (dccp_reqsk_init(req, dccp_sk(sk), skb))
		goto drop_and_free;

	dreq = dccp_rsk(req);
	if (dccp_parse_options(sk, dreq, skb))
		goto drop_and_free;

	if (security_inet_conn_request(sk, skb, req))
		goto drop_and_free;

	ireq = inet_rsk(req);
	ireq->ir_v6_rmt_addr = ipv6_hdr(skb)->saddr;
	ireq->ir_v6_loc_addr = ipv6_hdr(skb)->daddr;

	if (ipv6_opt_accepted(sk, skb) ||
	    np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo ||
	    np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) {
		atomic_inc(&skb->users);
		ireq->pktopts = skb;
	}
	ireq->ir_iif = sk->sk_bound_dev_if;

	/* So that link locals have meaning */
	if (!sk->sk_bound_dev_if &&
	    ipv6_addr_type(&ireq->ir_v6_rmt_addr) & IPV6_ADDR_LINKLOCAL)
		ireq->ir_iif = inet6_iif(skb);

	/*
	 * Step 3: Process LISTEN state
	 *
	 *   Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie
	 *
	 * Setting S.SWL/S.SWH to is deferred to dccp_create_openreq_child().
	 */
	dreq->dreq_isr	   = dcb->dccpd_seq;
	dreq->dreq_gsr     = dreq->dreq_isr;
	dreq->dreq_iss	   = dccp_v6_init_sequence(skb);
	dreq->dreq_gss     = dreq->dreq_iss;
	dreq->dreq_service = service;

	if (dccp_v6_send_response(sk, req))
		goto drop_and_free;

	inet6_csk_reqsk_queue_hash_add(sk, req, DCCP_TIMEOUT_INIT);
	return 0;

drop_and_free:
	reqsk_free(req);
drop:
	DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS);
	return -1;
}
Example #8
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);
}
Example #9
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((struct inet_timewait_sock *)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;

			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);
}
Example #10
0
static int dccp_v6_rcv(struct sk_buff *skb)
{
	const struct dccp_hdr *dh;
	bool refcounted;
	struct sock *sk;
	int min_cov;

	/* Step 1: Check header basics */

	if (dccp_invalid_packet(skb))
		goto discard_it;

	/* Step 1: If header checksum is incorrect, drop packet and return. */
	if (dccp_v6_csum_finish(skb, &ipv6_hdr(skb)->saddr,
				     &ipv6_hdr(skb)->daddr)) {
		DCCP_WARN("dropped packet with invalid checksum\n");
		goto discard_it;
	}

	dh = dccp_hdr(skb);

	DCCP_SKB_CB(skb)->dccpd_seq  = dccp_hdr_seq(dh);
	DCCP_SKB_CB(skb)->dccpd_type = dh->dccph_type;

	if (dccp_packet_without_ack(skb))
		DCCP_SKB_CB(skb)->dccpd_ack_seq = DCCP_PKT_WITHOUT_ACK_SEQ;
	else
		DCCP_SKB_CB(skb)->dccpd_ack_seq = dccp_hdr_ack_seq(skb);

lookup:
	sk = __inet6_lookup_skb(&dccp_hashinfo, skb, __dccp_hdr_len(dh),
			        dh->dccph_sport, dh->dccph_dport,
				inet6_iif(skb), &refcounted);
	if (!sk) {
		dccp_pr_debug("failed to look up flow ID in table and "
			      "get corresponding socket\n");
		goto no_dccp_socket;
	}

	/*
	 * Step 2:
	 *	... or S.state == TIMEWAIT,
	 *		Generate Reset(No Connection) unless P.type == Reset
	 *		Drop packet and return
	 */
	if (sk->sk_state == DCCP_TIME_WAIT) {
		dccp_pr_debug("sk->sk_state == DCCP_TIME_WAIT: do_time_wait\n");
		inet_twsk_put(inet_twsk(sk));
		goto no_dccp_socket;
	}

	if (sk->sk_state == DCCP_NEW_SYN_RECV) {
		struct request_sock *req = inet_reqsk(sk);
		struct sock *nsk;

		sk = req->rsk_listener;
		if (unlikely(sk->sk_state != DCCP_LISTEN)) {
			inet_csk_reqsk_queue_drop_and_put(sk, req);
			goto lookup;
		}
		sock_hold(sk);
		refcounted = true;
		nsk = dccp_check_req(sk, skb, req);
		if (!nsk) {
			reqsk_put(req);
			goto discard_and_relse;
		}
		if (nsk == sk) {
			reqsk_put(req);
		} else if (dccp_child_process(sk, nsk, skb)) {
			dccp_v6_ctl_send_reset(sk, skb);
			goto discard_and_relse;
		} else {
			sock_put(sk);
			return 0;
		}
	}
	/*
	 * RFC 4340, sec. 9.2.1: Minimum Checksum Coverage
	 *	o if MinCsCov = 0, only packets with CsCov = 0 are accepted
	 *	o if MinCsCov > 0, also accept packets with CsCov >= MinCsCov
	 */
	min_cov = dccp_sk(sk)->dccps_pcrlen;
	if (dh->dccph_cscov  &&  (min_cov == 0 || dh->dccph_cscov < min_cov))  {
		dccp_pr_debug("Packet CsCov %d does not satisfy MinCsCov %d\n",
			      dh->dccph_cscov, min_cov);
		/* FIXME: send Data Dropped option (see also dccp_v4_rcv) */
		goto discard_and_relse;
	}

	if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
		goto discard_and_relse;

	return sk_receive_skb(sk, skb, 1) ? -1 : 0;

no_dccp_socket:
	if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
		goto discard_it;
	/*
	 * Step 2:
	 *	If no socket ...
	 *		Generate Reset(No Connection) unless P.type == Reset
	 *		Drop packet and return
	 */
	if (dh->dccph_type != DCCP_PKT_RESET) {
		DCCP_SKB_CB(skb)->dccpd_reset_code =
					DCCP_RESET_CODE_NO_CONNECTION;
		dccp_v6_ctl_send_reset(sk, skb);
	}

discard_it:
	kfree_skb(skb);
	return 0;

discard_and_relse:
	if (refcounted)
		sock_put(sk);
	goto discard_it;
}
Example #11
0
static struct sock *dccp_v6_request_recv_sock(const struct sock *sk,
					      struct sk_buff *skb,
					      struct request_sock *req,
					      struct dst_entry *dst,
					      struct request_sock *req_unhash,
					      bool *own_req)
{
	struct inet_request_sock *ireq = inet_rsk(req);
	struct ipv6_pinfo *newnp;
	const struct ipv6_pinfo *np = inet6_sk(sk);
	struct ipv6_txoptions *opt;
	struct inet_sock *newinet;
	struct dccp6_sock *newdp6;
	struct sock *newsk;

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

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

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

		newnp->saddr = newsk->sk_v6_rcv_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;
	}


	if (sk_acceptq_is_full(sk))
		goto out_overflow;

	if (!dst) {
		struct flowi6 fl6;

		dst = inet6_csk_route_req(sk, &fl6, req, IPPROTO_DCCP);
		if (!dst)
			goto out;
	}

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

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

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

	newsk->sk_v6_daddr	= ireq->ir_v6_rmt_addr;
	newnp->saddr		= ireq->ir_v6_loc_addr;
	newsk->sk_v6_rcv_saddr	= ireq->ir_v6_loc_addr;
	newsk->sk_bound_dev_if	= ireq->ir_iif;

	/* Now IPv6 options...

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

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

	newnp->pktoptions = NULL;
	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.
	 */
	opt = rcu_dereference(np->opt);
	if (opt) {
		opt = ipv6_dup_options(newsk, opt);
		RCU_INIT_POINTER(newnp->opt, opt);
	}
	inet_csk(newsk)->icsk_ext_hdr_len = 0;
	if (opt)
		inet_csk(newsk)->icsk_ext_hdr_len = opt->opt_nflen +
						    opt->opt_flen;

	dccp_sync_mss(newsk, dst_mtu(dst));

	newinet->inet_daddr = newinet->inet_saddr = LOOPBACK4_IPV6;
	newinet->inet_rcv_saddr = LOOPBACK4_IPV6;

	if (__inet_inherit_port(sk, newsk) < 0) {
		inet_csk_prepare_forced_close(newsk);
		dccp_done(newsk);
		goto out;
	}
	*own_req = inet_ehash_nolisten(newsk, req_to_sk(req_unhash));
	/* Clone pktoptions received with SYN, if we own the req */
	if (*own_req && ireq->pktopts) {
		newnp->pktoptions = skb_clone(ireq->pktopts, GFP_ATOMIC);
		consume_skb(ireq->pktopts);
		ireq->pktopts = NULL;
		if (newnp->pktoptions)
			skb_set_owner_r(newnp->pktoptions, newsk);
	}

	return newsk;

out_overflow:
	__NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS);
out_nonewsk:
	dst_release(dst);
out:
	__NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENDROPS);
	return NULL;
}
Example #12
0
static int dccp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
			u8 type, u8 code, int offset, __be32 info)
{
	const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data;
	const struct dccp_hdr *dh;
	struct dccp_sock *dp;
	struct ipv6_pinfo *np;
	struct sock *sk;
	int err;
	__u64 seq;
	struct net *net = dev_net(skb->dev);

	/* Only need dccph_dport & dccph_sport which are the first
	 * 4 bytes in dccp header.
	 * Our caller (icmpv6_notify()) already pulled 8 bytes for us.
	 */
	BUILD_BUG_ON(offsetofend(struct dccp_hdr, dccph_sport) > 8);
	BUILD_BUG_ON(offsetofend(struct dccp_hdr, dccph_dport) > 8);
	dh = (struct dccp_hdr *)(skb->data + offset);

	sk = __inet6_lookup_established(net, &dccp_hashinfo,
					&hdr->daddr, dh->dccph_dport,
					&hdr->saddr, ntohs(dh->dccph_sport),
					inet6_iif(skb), 0);

	if (!sk) {
		__ICMP6_INC_STATS(net, __in6_dev_get(skb->dev),
				  ICMP6_MIB_INERRORS);
		return -ENOENT;
	}

	if (sk->sk_state == DCCP_TIME_WAIT) {
		inet_twsk_put(inet_twsk(sk));
		return 0;
	}
	seq = dccp_hdr_seq(dh);
	if (sk->sk_state == DCCP_NEW_SYN_RECV) {
		dccp_req_err(sk, seq);
		return 0;
	}

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

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

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

	np = inet6_sk(sk);

	if (type == NDISC_REDIRECT) {
		if (!sock_owned_by_user(sk)) {
			struct dst_entry *dst = __sk_dst_check(sk, np->dst_cookie);

			if (dst)
				dst->ops->redirect(dst, sk, skb);
		}
		goto out;
	}

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

		if (!ip6_sk_accept_pmtu(sk))
			goto out;

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

		dst = inet6_csk_update_pmtu(sk, ntohl(info));
		if (!dst)
			goto out;

		if (inet_csk(sk)->icsk_pmtu_cookie > dst_mtu(dst))
			dccp_sync_mss(sk, dst_mtu(dst));
		goto out;
	}

	icmpv6_err_convert(type, code, &err);

	/* Might be for an request_sock */
	switch (sk->sk_state) {
	case DCCP_REQUESTING:
	case DCCP_RESPOND:  /* Cannot happen.
			       It can, it SYNs are crossed. --ANK */
		if (!sock_owned_by_user(sk)) {
			__DCCP_INC_STATS(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);
	return 0;
}
Example #13
0
/* The socket must have it's spinlock held when we get
 * here.
 *
 * We have a potential double-lock case here, so even when
 * doing backlog processing we use the BH locking scheme.
 * This is because we cannot sleep with the original spinlock
 * held.
 */
static int dccp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
{
	struct ipv6_pinfo *np = inet6_sk(sk);
	struct sk_buff *opt_skb = NULL;

	/* Imagine: socket is IPv6. IPv4 packet arrives,
	   goes to IPv4 receive handler and backlogged.
	   From backlog it always goes here. Kerboom...
	   Fortunately, dccp_rcv_established and rcv_established
	   handle them correctly, but it is not case with
	   dccp_v6_hnd_req and dccp_v6_ctl_send_reset().   --ANK
	 */

	if (skb->protocol == htons(ETH_P_IP))
		return dccp_v4_do_rcv(sk, skb);

	if (sk_filter(sk, skb))
		goto discard;

	/*
	 * socket locking is here for SMP purposes as backlog rcv is currently
	 * called with bh processing disabled.
	 */

	/* Do Stevens' IPV6_PKTOPTIONS.

	   Yes, guys, it is the only place in our code, where we
	   may make it not affecting IPv4.
	   The rest of code is protocol independent,
	   and I do not like idea to uglify IPv4.

	   Actually, all the idea behind IPV6_PKTOPTIONS
	   looks not very well thought. For now we latch
	   options, received in the last packet, enqueued
	   by tcp. Feel free to propose better solution.
					       --ANK (980728)
	 */
	if (np->rxopt.all)
		opt_skb = skb_clone(skb, GFP_ATOMIC);

	if (sk->sk_state == DCCP_OPEN) { /* Fast path */
		if (dccp_rcv_established(sk, skb, dccp_hdr(skb), skb->len))
			goto reset;
		if (opt_skb)
			goto ipv6_pktoptions;
		return 0;
	}

	/*
	 *  Step 3: Process LISTEN state
	 *     If S.state == LISTEN,
	 *	 If P.type == Request or P contains a valid Init Cookie option,
	 *	      (* Must scan the packet's options to check for Init
	 *		 Cookies.  Only Init Cookies are processed here,
	 *		 however; other options are processed in Step 8.  This
	 *		 scan need only be performed if the endpoint uses Init
	 *		 Cookies *)
	 *	      (* Generate a new socket and switch to that socket *)
	 *	      Set S := new socket for this port pair
	 *	      S.state = RESPOND
	 *	      Choose S.ISS (initial seqno) or set from Init Cookies
	 *	      Initialize S.GAR := S.ISS
	 *	      Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookies
	 *	      Continue with S.state == RESPOND
	 *	      (* A Response packet will be generated in Step 11 *)
	 *	 Otherwise,
	 *	      Generate Reset(No Connection) unless P.type == Reset
	 *	      Drop packet and return
	 *
	 * NOTE: the check for the packet types is done in
	 *	 dccp_rcv_state_process
	 */

	if (dccp_rcv_state_process(sk, skb, dccp_hdr(skb), skb->len))
		goto reset;
	if (opt_skb)
		goto ipv6_pktoptions;
	return 0;

reset:
	dccp_v6_ctl_send_reset(sk, skb);
discard:
	if (opt_skb != NULL)
		__kfree_skb(opt_skb);
	kfree_skb(skb);
	return 0;

/* Handling IPV6_PKTOPTIONS skb the similar
 * way it's done for net/ipv6/tcp_ipv6.c
 */
ipv6_pktoptions:
	if (!((1 << sk->sk_state) & (DCCPF_CLOSED | DCCPF_LISTEN))) {
		if (np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo)
			np->mcast_oif = inet6_iif(opt_skb);
		if (np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim)
			np->mcast_hops = ipv6_hdr(opt_skb)->hop_limit;
		if (np->rxopt.bits.rxflow || np->rxopt.bits.rxtclass)
			np->rcv_flowinfo = ip6_flowinfo(ipv6_hdr(opt_skb));
		if (np->repflow)
			np->flow_label = ip6_flowlabel(ipv6_hdr(opt_skb));
		if (ipv6_opt_accepted(sk, opt_skb,
				      &DCCP_SKB_CB(opt_skb)->header.h6)) {
			skb_set_owner_r(opt_skb, sk);
			memmove(IP6CB(opt_skb),
				&DCCP_SKB_CB(opt_skb)->header.h6,
				sizeof(struct inet6_skb_parm));
			opt_skb = xchg(&np->pktoptions, opt_skb);
		} else {
			__kfree_skb(opt_skb);
			opt_skb = xchg(&np->pktoptions, NULL);
		}
	}

	kfree_skb(opt_skb);
	return 0;
}
Example #14
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;
}