ipv4.c 34.0 KB
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/*
 *  net/dccp/ipv4.c
 *
 *  An implementation of the DCCP protocol
 *  Arnaldo Carvalho de Melo <acme@conectiva.com.br>
 *
 *	This program is free software; you can redistribute it and/or
 *	modify it under the terms of the GNU General Public License
 *	as published by the Free Software Foundation; either version
 *	2 of the License, or (at your option) any later version.
 */

#include <linux/config.h>
#include <linux/dccp.h>
#include <linux/icmp.h>
#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/random.h>

#include <net/icmp.h>
#include <net/inet_hashtables.h>
#include <net/sock.h>
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#include <net/timewait_sock.h>
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#include <net/tcp_states.h>
#include <net/xfrm.h>

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#include "ackvec.h"
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#include "ccid.h"
#include "dccp.h"

struct inet_hashinfo __cacheline_aligned dccp_hashinfo = {
	.lhash_lock	= RW_LOCK_UNLOCKED,
	.lhash_users	= ATOMIC_INIT(0),
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	.lhash_wait = __WAIT_QUEUE_HEAD_INITIALIZER(dccp_hashinfo.lhash_wait),
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};

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EXPORT_SYMBOL_GPL(dccp_hashinfo);

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static int dccp_v4_get_port(struct sock *sk, const unsigned short snum)
{
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	return inet_csk_get_port(&dccp_hashinfo, sk, snum,
				 inet_csk_bind_conflict);
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}

static void dccp_v4_hash(struct sock *sk)
{
	inet_hash(&dccp_hashinfo, sk);
}

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void dccp_unhash(struct sock *sk)
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{
	inet_unhash(&dccp_hashinfo, sk);
}

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EXPORT_SYMBOL_GPL(dccp_unhash);

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/* called with local bh disabled */
static int __dccp_v4_check_established(struct sock *sk, const __u16 lport,
				      struct inet_timewait_sock **twp)
{
	struct inet_sock *inet = inet_sk(sk);
	const u32 daddr = inet->rcv_saddr;
	const u32 saddr = inet->daddr;
	const int dif = sk->sk_bound_dev_if;
	INET_ADDR_COOKIE(acookie, saddr, daddr)
	const __u32 ports = INET_COMBINED_PORTS(inet->dport, lport);
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	unsigned int hash = inet_ehashfn(daddr, lport, saddr, inet->dport);
	struct inet_ehash_bucket *head = inet_ehash_bucket(&dccp_hashinfo, hash);
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	const struct sock *sk2;
	const struct hlist_node *node;
	struct inet_timewait_sock *tw;

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	prefetch(head->chain.first);
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	write_lock(&head->lock);

	/* Check TIME-WAIT sockets first. */
	sk_for_each(sk2, node, &(head + dccp_hashinfo.ehash_size)->chain) {
		tw = inet_twsk(sk2);

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		if (INET_TW_MATCH(sk2, hash, acookie, saddr, daddr, ports, dif))
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			goto not_unique;
	}
	tw = NULL;

	/* And established part... */
	sk_for_each(sk2, node, &head->chain) {
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		if (INET_MATCH(sk2, hash, acookie, saddr, daddr, ports, dif))
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			goto not_unique;
	}

	/* Must record num and sport now. Otherwise we will see
	 * in hash table socket with a funny identity. */
	inet->num = lport;
	inet->sport = htons(lport);
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	sk->sk_hash = hash;
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	BUG_TRAP(sk_unhashed(sk));
	__sk_add_node(sk, &head->chain);
	sock_prot_inc_use(sk->sk_prot);
	write_unlock(&head->lock);

	if (twp != NULL) {
		*twp = tw;
		NET_INC_STATS_BH(LINUX_MIB_TIMEWAITRECYCLED);
	} else if (tw != NULL) {
		/* Silly. Should hash-dance instead... */
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		inet_twsk_deschedule(tw, &dccp_death_row);
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		NET_INC_STATS_BH(LINUX_MIB_TIMEWAITRECYCLED);

		inet_twsk_put(tw);
	}

	return 0;

not_unique:
	write_unlock(&head->lock);
	return -EADDRNOTAVAIL;
}

/*
 * Bind a port for a connect operation and hash it.
 */
static int dccp_v4_hash_connect(struct sock *sk)
{
	const unsigned short snum = inet_sk(sk)->num;
 	struct inet_bind_hashbucket *head;
 	struct inet_bind_bucket *tb;
	int ret;

 	if (snum == 0) {
 		int low = sysctl_local_port_range[0];
 		int high = sysctl_local_port_range[1];
 		int remaining = (high - low) + 1;
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 		int rover = net_random() % (high - low) + low;
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		struct hlist_node *node;
 		struct inet_timewait_sock *tw = NULL;

 		local_bh_disable();
 		do {
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 			head = &dccp_hashinfo.bhash[inet_bhashfn(rover,
						    dccp_hashinfo.bhash_size)];
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 			spin_lock(&head->lock);

 			/* Does not bother with rcv_saddr checks,
 			 * because the established check is already
 			 * unique enough.
 			 */
			inet_bind_bucket_for_each(tb, node, &head->chain) {
 				if (tb->port == rover) {
 					BUG_TRAP(!hlist_empty(&tb->owners));
 					if (tb->fastreuse >= 0)
 						goto next_port;
 					if (!__dccp_v4_check_established(sk,
									 rover,
									 &tw))
 						goto ok;
 					goto next_port;
 				}
 			}

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 			tb = inet_bind_bucket_create(dccp_hashinfo.bind_bucket_cachep,
						     head, rover);
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 			if (tb == NULL) {
 				spin_unlock(&head->lock);
 				break;
 			}
 			tb->fastreuse = -1;
 			goto ok;

 		next_port:
 			spin_unlock(&head->lock);
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 			if (++rover > high)
 				rover = low;
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 		} while (--remaining > 0);

 		local_bh_enable();

 		return -EADDRNOTAVAIL;

ok:
 		/* All locks still held and bhs disabled */
 		inet_bind_hash(sk, tb, rover);
		if (sk_unhashed(sk)) {
 			inet_sk(sk)->sport = htons(rover);
 			__inet_hash(&dccp_hashinfo, sk, 0);
 		}
 		spin_unlock(&head->lock);

 		if (tw != NULL) {
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 			inet_twsk_deschedule(tw, &dccp_death_row);
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 			inet_twsk_put(tw);
 		}

		ret = 0;
		goto out;
 	}

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 	head = &dccp_hashinfo.bhash[inet_bhashfn(snum,
						 dccp_hashinfo.bhash_size)];
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 	tb   = inet_csk(sk)->icsk_bind_hash;
	spin_lock_bh(&head->lock);
	if (sk_head(&tb->owners) == sk && sk->sk_bind_node.next == NULL) {
		__inet_hash(&dccp_hashinfo, sk, 0);
		spin_unlock_bh(&head->lock);
		return 0;
	} else {
		spin_unlock(&head->lock);
		/* No definite answer... Walk to established hash table */
		ret = __dccp_v4_check_established(sk, snum, NULL);
out:
		local_bh_enable();
		return ret;
	}
}

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int dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
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{
	struct inet_sock *inet = inet_sk(sk);
	struct dccp_sock *dp = dccp_sk(sk);
	const struct sockaddr_in *usin = (struct sockaddr_in *)uaddr;
	struct rtable *rt;
	u32 daddr, nexthop;
	int tmp;
	int err;

	dp->dccps_role = DCCP_ROLE_CLIENT;

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	if (dccp_service_not_initialized(sk))
		return -EPROTO;

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	if (addr_len < sizeof(struct sockaddr_in))
		return -EINVAL;

	if (usin->sin_family != AF_INET)
		return -EAFNOSUPPORT;

	nexthop = daddr = usin->sin_addr.s_addr;
	if (inet->opt != NULL && inet->opt->srr) {
		if (daddr == 0)
			return -EINVAL;
		nexthop = inet->opt->faddr;
	}

	tmp = ip_route_connect(&rt, nexthop, inet->saddr,
			       RT_CONN_FLAGS(sk), sk->sk_bound_dev_if,
			       IPPROTO_DCCP,
			       inet->sport, usin->sin_port, sk);
	if (tmp < 0)
		return tmp;

	if (rt->rt_flags & (RTCF_MULTICAST | RTCF_BROADCAST)) {
		ip_rt_put(rt);
		return -ENETUNREACH;
	}

	if (inet->opt == NULL || !inet->opt->srr)
		daddr = rt->rt_dst;

	if (inet->saddr == 0)
		inet->saddr = rt->rt_src;
	inet->rcv_saddr = inet->saddr;

	inet->dport = usin->sin_port;
	inet->daddr = daddr;

	dp->dccps_ext_header_len = 0;
	if (inet->opt != NULL)
		dp->dccps_ext_header_len = inet->opt->optlen;
	/*
	 * Socket identity is still unknown (sport may be zero).
	 * However we set state to DCCP_REQUESTING and not releasing socket
	 * lock select source port, enter ourselves into the hash tables and
	 * complete initialization after this.
	 */
	dccp_set_state(sk, DCCP_REQUESTING);
	err = dccp_v4_hash_connect(sk);
	if (err != 0)
		goto failure;

	err = ip_route_newports(&rt, inet->sport, inet->dport, sk);
	if (err != 0)
		goto failure;

	/* OK, now commit destination to socket.  */
	sk_setup_caps(sk, &rt->u.dst);

	dp->dccps_gar =
		dp->dccps_iss = secure_dccp_sequence_number(inet->saddr,
							    inet->daddr,
							    inet->sport,
							    usin->sin_port);
	dccp_update_gss(sk, dp->dccps_iss);

	inet->id = dp->dccps_iss ^ jiffies;

	err = dccp_connect(sk);
	rt = NULL;
	if (err != 0)
		goto failure;
out:
	return err;
failure:
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	/*
	 * This unhashes the socket and releases the local port, if necessary.
	 */
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	dccp_set_state(sk, DCCP_CLOSED);
	ip_rt_put(rt);
	sk->sk_route_caps = 0;
	inet->dport = 0;
	goto out;
}

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EXPORT_SYMBOL_GPL(dccp_v4_connect);

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/*
 * This routine does path mtu discovery as defined in RFC1191.
 */
static inline void dccp_do_pmtu_discovery(struct sock *sk,
					  const struct iphdr *iph,
					  u32 mtu)
{
	struct dst_entry *dst;
	const struct inet_sock *inet = inet_sk(sk);
	const struct dccp_sock *dp = dccp_sk(sk);

	/* We are not interested in DCCP_LISTEN and request_socks (RESPONSEs
	 * send out by Linux are always < 576bytes so they should go through
	 * unfragmented).
	 */
	if (sk->sk_state == DCCP_LISTEN)
		return;

	/* We don't check in the destentry if pmtu discovery is forbidden
	 * on this route. We just assume that no packet_to_big packets
	 * are send back when pmtu discovery is not active.
     	 * There is a small race when the user changes this flag in the
	 * route, but I think that's acceptable.
	 */
	if ((dst = __sk_dst_check(sk, 0)) == NULL)
		return;

	dst->ops->update_pmtu(dst, mtu);

	/* Something is about to be wrong... Remember soft error
	 * for the case, if this connection will not able to recover.
	 */
	if (mtu < dst_mtu(dst) && ip_dont_fragment(sk, dst))
		sk->sk_err_soft = EMSGSIZE;

	mtu = dst_mtu(dst);

	if (inet->pmtudisc != IP_PMTUDISC_DONT &&
	    dp->dccps_pmtu_cookie > mtu) {
		dccp_sync_mss(sk, mtu);

		/*
		 * From: draft-ietf-dccp-spec-11.txt
		 *
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		 *	DCCP-Sync packets are the best choice for upward
		 *	probing, since DCCP-Sync probes do not risk application
		 *	data loss.
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		 */
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		dccp_send_sync(sk, dp->dccps_gsr, DCCP_PKT_SYNC);
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	} /* else let the usual retransmit timer handle it */
}

static void dccp_v4_ctl_send_ack(struct sk_buff *rxskb)
{
	int err;
	struct dccp_hdr *rxdh = dccp_hdr(rxskb), *dh;
	const int dccp_hdr_ack_len = sizeof(struct dccp_hdr) +
				     sizeof(struct dccp_hdr_ext) +
				     sizeof(struct dccp_hdr_ack_bits);
	struct sk_buff *skb;

	if (((struct rtable *)rxskb->dst)->rt_type != RTN_LOCAL)
		return;

	skb = alloc_skb(MAX_DCCP_HEADER + 15, GFP_ATOMIC);
	if (skb == NULL)
		return;

	/* Reserve space for headers. */
	skb_reserve(skb, MAX_DCCP_HEADER);

	skb->dst = dst_clone(rxskb->dst);

	skb->h.raw = skb_push(skb, dccp_hdr_ack_len);
	dh = dccp_hdr(skb);
	memset(dh, 0, dccp_hdr_ack_len);

	/* Build DCCP header and checksum it. */
	dh->dccph_type	   = DCCP_PKT_ACK;
	dh->dccph_sport	   = rxdh->dccph_dport;
	dh->dccph_dport	   = rxdh->dccph_sport;
	dh->dccph_doff	   = dccp_hdr_ack_len / 4;
	dh->dccph_x	   = 1;

	dccp_hdr_set_seq(dh, DCCP_SKB_CB(rxskb)->dccpd_ack_seq);
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	dccp_hdr_set_ack(dccp_hdr_ack_bits(skb),
			 DCCP_SKB_CB(rxskb)->dccpd_seq);
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	bh_lock_sock(dccp_ctl_socket->sk);
	err = ip_build_and_send_pkt(skb, dccp_ctl_socket->sk,
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				    rxskb->nh.iph->daddr,
				    rxskb->nh.iph->saddr, NULL);
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	bh_unlock_sock(dccp_ctl_socket->sk);

	if (err == NET_XMIT_CN || err == 0) {
		DCCP_INC_STATS_BH(DCCP_MIB_OUTSEGS);
		DCCP_INC_STATS_BH(DCCP_MIB_OUTRSTS);
	}
}

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static void dccp_v4_reqsk_send_ack(struct sk_buff *skb,
				   struct request_sock *req)
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{
	dccp_v4_ctl_send_ack(skb);
}

static int dccp_v4_send_response(struct sock *sk, struct request_sock *req,
				 struct dst_entry *dst)
{
	int err = -1;
	struct sk_buff *skb;

	/* First, grab a route. */
	
	if (dst == NULL && (dst = inet_csk_route_req(sk, req)) == NULL)
		goto out;

	skb = dccp_make_response(sk, dst, req);
	if (skb != NULL) {
		const struct inet_request_sock *ireq = inet_rsk(req);

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Herbert Xu 已提交
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		memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
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		err = ip_build_and_send_pkt(skb, sk, ireq->loc_addr,
					    ireq->rmt_addr,
					    ireq->opt);
		if (err == NET_XMIT_CN)
			err = 0;
	}

out:
	dst_release(dst);
	return err;
}

/*
 * This routine is called by the ICMP module when it gets some sort of error
 * condition. If err < 0 then the socket should be closed and the error
 * returned to the user. If err > 0 it's just the icmp type << 8 | icmp code.
 * After adjustment header points to the first 8 bytes of the tcp header. We
 * need to find the appropriate port.
 *
 * The locking strategy used here is very "optimistic". When someone else
 * accesses the socket the ICMP is just dropped and for some paths there is no
 * check at all. A more general error queue to queue errors for later handling
 * is probably better.
 */
void dccp_v4_err(struct sk_buff *skb, u32 info)
{
	const struct iphdr *iph = (struct iphdr *)skb->data;
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	const struct dccp_hdr *dh = (struct dccp_hdr *)(skb->data +
							(iph->ihl << 2));
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	struct dccp_sock *dp;
	struct inet_sock *inet;
	const int type = skb->h.icmph->type;
	const int code = skb->h.icmph->code;
	struct sock *sk;
	__u64 seq;
	int err;

	if (skb->len < (iph->ihl << 2) + 8) {
		ICMP_INC_STATS_BH(ICMP_MIB_INERRORS);
		return;
	}

	sk = inet_lookup(&dccp_hashinfo, iph->daddr, dh->dccph_dport,
			 iph->saddr, dh->dccph_sport, inet_iif(skb));
	if (sk == NULL) {
		ICMP_INC_STATS_BH(ICMP_MIB_INERRORS);
		return;
	}

	if (sk->sk_state == DCCP_TIME_WAIT) {
		inet_twsk_put((struct inet_timewait_sock *)sk);
		return;
	}

	bh_lock_sock(sk);
	/* If too many ICMPs get dropped on busy
	 * servers this needs to be solved differently.
	 */
	if (sock_owned_by_user(sk))
		NET_INC_STATS_BH(LINUX_MIB_LOCKDROPPEDICMPS);

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

	dp = dccp_sk(sk);
	seq = dccp_hdr_seq(skb);
	if (sk->sk_state != DCCP_LISTEN &&
	    !between48(seq, dp->dccps_swl, dp->dccps_swh)) {
		NET_INC_STATS(LINUX_MIB_OUTOFWINDOWICMPS);
		goto out;
	}

	switch (type) {
	case ICMP_SOURCE_QUENCH:
		/* Just silently ignore these. */
		goto out;
	case ICMP_PARAMETERPROB:
		err = EPROTO;
		break;
	case ICMP_DEST_UNREACH:
		if (code > NR_ICMP_UNREACH)
			goto out;

		if (code == ICMP_FRAG_NEEDED) { /* PMTU discovery (RFC1191) */
			if (!sock_owned_by_user(sk))
				dccp_do_pmtu_discovery(sk, iph, info);
			goto out;
		}

		err = icmp_err_convert[code].errno;
		break;
	case ICMP_TIME_EXCEEDED:
		err = EHOSTUNREACH;
		break;
	default:
		goto out;
	}

	switch (sk->sk_state) {
		struct request_sock *req , **prev;
	case DCCP_LISTEN:
		if (sock_owned_by_user(sk))
			goto out;
		req = inet_csk_search_req(sk, &prev, dh->dccph_dport,
					  iph->daddr, iph->saddr);
		if (!req)
			goto out;

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

		if (seq != dccp_rsk(req)->dreq_iss) {
			NET_INC_STATS_BH(LINUX_MIB_OUTOFWINDOWICMPS);
			goto out;
		}
		/*
		 * Still in RESPOND, just remove it silently.
		 * There is no good way to pass the error to the newly
		 * created socket, and POSIX does not want network
		 * errors returned from accept().
		 */
		inet_csk_reqsk_queue_drop(sk, req, prev);
		goto out;

	case DCCP_REQUESTING:
	case DCCP_RESPOND:
		if (!sock_owned_by_user(sk)) {
			DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS);
			sk->sk_err = err;

			sk->sk_error_report(sk);

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

	/* If we've already connected we will keep trying
	 * until we time out, or the user gives up.
	 *
	 * rfc1122 4.2.3.9 allows to consider as hard errors
	 * only PROTO_UNREACH and PORT_UNREACH (well, FRAG_FAILED too,
	 * but it is obsoleted by pmtu discovery).
	 *
	 * Note, that in modern internet, where routing is unreliable
	 * and in each dark corner broken firewalls sit, sending random
	 * errors ordered by their masters even this two messages finally lose
	 * their original sense (even Linux sends invalid PORT_UNREACHs)
	 *
	 * Now we are in compliance with RFCs.
	 *							--ANK (980905)
	 */

	inet = inet_sk(sk);
	if (!sock_owned_by_user(sk) && inet->recverr) {
		sk->sk_err = err;
		sk->sk_error_report(sk);
	} else /* Only an error on timeout */
		sk->sk_err_soft = err;
out:
	bh_unlock_sock(sk);
	sock_put(sk);
}

604
/* This routine computes an IPv4 DCCP checksum. */
605
void dccp_v4_send_check(struct sock *sk, int len, struct sk_buff *skb)
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{
	const struct inet_sock *inet = inet_sk(sk);
	struct dccp_hdr *dh = dccp_hdr(skb);

	dh->dccph_checksum = dccp_v4_checksum(skb, inet->saddr, inet->daddr);
}

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EXPORT_SYMBOL_GPL(dccp_v4_send_check);

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int dccp_v4_send_reset(struct sock *sk, enum dccp_reset_codes code)
{
	struct sk_buff *skb;
	/*
	 * FIXME: what if rebuild_header fails?
	 * Should we be doing a rebuild_header here?
	 */
	int err = inet_sk_rebuild_header(sk);

	if (err != 0)
		return err;

	skb = dccp_make_reset(sk, sk->sk_dst_cache, code);
	if (skb != NULL) {
		const struct inet_sock *inet = inet_sk(sk);

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Herbert Xu 已提交
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		memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
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		err = ip_build_and_send_pkt(skb, sk,
					    inet->saddr, inet->daddr, NULL);
		if (err == NET_XMIT_CN)
			err = 0;
	}

	return err;
}

static inline u64 dccp_v4_init_sequence(const struct sock *sk,
					const struct sk_buff *skb)
{
	return secure_dccp_sequence_number(skb->nh.iph->daddr,
					   skb->nh.iph->saddr,
					   dccp_hdr(skb)->dccph_dport,
					   dccp_hdr(skb)->dccph_sport);
}

int dccp_v4_conn_request(struct sock *sk, struct sk_buff *skb)
{
	struct inet_request_sock *ireq;
	struct dccp_sock dp;
	struct request_sock *req;
	struct dccp_request_sock *dreq;
	const __u32 saddr = skb->nh.iph->saddr;
	const __u32 daddr = skb->nh.iph->daddr;
658
 	const __u32 service = dccp_hdr_request(skb)->dccph_req_service;
659 660
	struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb);
	__u8 reset_code = DCCP_RESET_CODE_TOO_BUSY;
661 662 663

	/* Never answer to DCCP_PKT_REQUESTs send to broadcast or multicast */
	if (((struct rtable *)skb->dst)->rt_flags &
664 665
	    (RTCF_BROADCAST | RTCF_MULTICAST)) {
		reset_code = DCCP_RESET_CODE_NO_CONNECTION;
666
		goto drop;
667
	}
668

669 670 671 672
	if (dccp_bad_service_code(sk, service)) {
		reset_code = DCCP_RESET_CODE_BAD_SERVICE_CODE;
		goto drop;
 	}
673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700
	/*
	 * TW buckets are converted to open requests without
	 * limitations, they conserve resources and peer is
	 * evidently real one.
	 */
	if (inet_csk_reqsk_queue_is_full(sk))
		goto drop;

	/*
	 * Accept backlog is full. If we have already queued enough
	 * of warm entries in syn queue, drop request. It is better than
	 * clogging syn queue with openreqs with exponentially increasing
	 * timeout.
	 */
	if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1)
		goto drop;

	req = reqsk_alloc(sk->sk_prot->rsk_prot);
	if (req == NULL)
		goto drop;

	/* FIXME: process options */

	dccp_openreq_init(req, &dp, skb);

	ireq = inet_rsk(req);
	ireq->loc_addr = daddr;
	ireq->rmt_addr = saddr;
701 702
	req->rcv_wnd	= 100; /* Fake, option parsing will get the
				  right value */
703 704 705 706 707 708 709 710 711 712 713
	ireq->opt	= NULL;

	/* 
	 * Step 3: Process LISTEN state
	 *
	 * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie
	 *
	 * In fact we defer setting S.GSR, S.SWL, S.SWH to
	 * dccp_create_openreq_child.
	 */
	dreq = dccp_rsk(req);
714 715 716
	dreq->dreq_isr	   = dcb->dccpd_seq;
	dreq->dreq_iss	   = dccp_v4_init_sequence(sk, skb);
	dreq->dreq_service = service;
717

718
	if (dccp_v4_send_response(sk, req, NULL))
719 720 721 722 723 724
		goto drop_and_free;

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

drop_and_free:
725
	reqsk_free(req);
726 727
drop:
	DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS);
728
	dcb->dccpd_reset_code = reset_code;
729 730 731
	return -1;
}

732 733
EXPORT_SYMBOL_GPL(dccp_v4_conn_request);

734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787
/*
 * The three way handshake has completed - we got a valid ACK or DATAACK -
 * now create the new socket.
 *
 * This is the equivalent of TCP's tcp_v4_syn_recv_sock
 */
struct sock *dccp_v4_request_recv_sock(struct sock *sk, struct sk_buff *skb,
				       struct request_sock *req,
				       struct dst_entry *dst)
{
	struct inet_request_sock *ireq;
	struct inet_sock *newinet;
	struct dccp_sock *newdp;
	struct sock *newsk;

	if (sk_acceptq_is_full(sk))
		goto exit_overflow;

	if (dst == NULL && (dst = inet_csk_route_req(sk, req)) == NULL)
		goto exit;

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

	sk_setup_caps(newsk, dst);

	newdp		   = dccp_sk(newsk);
	newinet		   = inet_sk(newsk);
	ireq		   = inet_rsk(req);
	newinet->daddr	   = ireq->rmt_addr;
	newinet->rcv_saddr = ireq->loc_addr;
	newinet->saddr	   = ireq->loc_addr;
	newinet->opt	   = ireq->opt;
	ireq->opt	   = NULL;
	newinet->mc_index  = inet_iif(skb);
	newinet->mc_ttl	   = skb->nh.iph->ttl;
	newinet->id	   = jiffies;

	dccp_sync_mss(newsk, dst_mtu(dst));

	__inet_hash(&dccp_hashinfo, newsk, 0);
	__inet_inherit_port(&dccp_hashinfo, sk, newsk);

	return newsk;

exit_overflow:
	NET_INC_STATS_BH(LINUX_MIB_LISTENOVERFLOWS);
exit:
	NET_INC_STATS_BH(LINUX_MIB_LISTENDROPS);
	dst_release(dst);
	return NULL;
}

788 789
EXPORT_SYMBOL_GPL(dccp_v4_request_recv_sock);

790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818
static struct sock *dccp_v4_hnd_req(struct sock *sk, struct sk_buff *skb)
{
	const struct dccp_hdr *dh = dccp_hdr(skb);
	const struct iphdr *iph = skb->nh.iph;
	struct sock *nsk;
	struct request_sock **prev;
	/* Find possible connection requests. */
	struct request_sock *req = inet_csk_search_req(sk, &prev,
						       dh->dccph_sport,
						       iph->saddr, iph->daddr);
	if (req != NULL)
		return dccp_check_req(sk, skb, req, prev);

	nsk = __inet_lookup_established(&dccp_hashinfo,
					iph->saddr, dh->dccph_sport,
					iph->daddr, ntohs(dh->dccph_dport),
					inet_iif(skb));
	if (nsk != NULL) {
		if (nsk->sk_state != DCCP_TIME_WAIT) {
			bh_lock_sock(nsk);
			return nsk;
		}
		inet_twsk_put((struct inet_timewait_sock *)nsk);
		return NULL;
	}

	return sk;
}

819 820
int dccp_v4_checksum(const struct sk_buff *skb, const u32 saddr,
		     const u32 daddr)
821
{
822
	const struct dccp_hdr* dh = dccp_hdr(skb);
823 824 825 826 827 828 829
	int checksum_len;
	u32 tmp;

	if (dh->dccph_cscov == 0)
		checksum_len = skb->len;
	else {
		checksum_len = (dh->dccph_cscov + dh->dccph_x) * sizeof(u32);
830 831
		checksum_len = checksum_len < skb->len ? checksum_len :
							 skb->len;
832 833 834
	}

	tmp = csum_partial((unsigned char *)dh, checksum_len, 0);
835 836
	return csum_tcpudp_magic(saddr, daddr, checksum_len,
				 IPPROTO_DCCP, tmp);
837 838
}

839 840
static int dccp_v4_verify_checksum(struct sk_buff *skb,
				   const u32 saddr, const u32 daddr)
841
{
842 843 844
	struct dccp_hdr *dh = dccp_hdr(skb);
	int checksum_len;
	u32 tmp;
845

846 847 848 849
	if (dh->dccph_cscov == 0)
		checksum_len = skb->len;
	else {
		checksum_len = (dh->dccph_cscov + dh->dccph_x) * sizeof(u32);
850 851
		checksum_len = checksum_len < skb->len ? checksum_len :
							 skb->len;
852 853
	}
	tmp = csum_partial((unsigned char *)dh, checksum_len, 0);
854 855
	return csum_tcpudp_magic(saddr, daddr, checksum_len,
				 IPPROTO_DCCP, tmp) == 0 ? 0 : -1;
856 857 858 859 860 861 862 863 864 865 866 867 868 869
}

static struct dst_entry* dccp_v4_route_skb(struct sock *sk,
					   struct sk_buff *skb)
{
	struct rtable *rt;
	struct flowi fl = { .oif = ((struct rtable *)skb->dst)->rt_iif,
			    .nl_u = { .ip4_u =
				      { .daddr = skb->nh.iph->saddr,
					.saddr = skb->nh.iph->daddr,
					.tos = RT_CONN_FLAGS(sk) } },
			    .proto = sk->sk_protocol,
			    .uli_u = { .ports =
				       { .sport = dccp_hdr(skb)->dccph_dport,
870 871 872
					 .dport = dccp_hdr(skb)->dccph_sport }
			   	     }
			  };
873 874 875 876 877 878 879 880 881

	if (ip_route_output_flow(&rt, &fl, sk, 0)) {
		IP_INC_STATS_BH(IPSTATS_MIB_OUTNOROUTES);
		return NULL;
	}

	return &rt->u.dst;
}

882
static void dccp_v4_ctl_send_reset(struct sk_buff *rxskb)
883 884 885 886 887 888 889 890
{
	int err;
	struct dccp_hdr *rxdh = dccp_hdr(rxskb), *dh;
	const int dccp_hdr_reset_len = sizeof(struct dccp_hdr) +
				       sizeof(struct dccp_hdr_ext) +
				       sizeof(struct dccp_hdr_reset);
	struct sk_buff *skb;
	struct dst_entry *dst;
891
	u64 seqno;
892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921

	/* Never send a reset in response to a reset. */
	if (rxdh->dccph_type == DCCP_PKT_RESET)
		return;

	if (((struct rtable *)rxskb->dst)->rt_type != RTN_LOCAL)
		return;

	dst = dccp_v4_route_skb(dccp_ctl_socket->sk, rxskb);
	if (dst == NULL)
		return;

	skb = alloc_skb(MAX_DCCP_HEADER + 15, GFP_ATOMIC);
	if (skb == NULL)
		goto out;

	/* Reserve space for headers. */
	skb_reserve(skb, MAX_DCCP_HEADER);
	skb->dst = dst_clone(dst);

	skb->h.raw = skb_push(skb, dccp_hdr_reset_len);
	dh = dccp_hdr(skb);
	memset(dh, 0, dccp_hdr_reset_len);

	/* Build DCCP header and checksum it. */
	dh->dccph_type	   = DCCP_PKT_RESET;
	dh->dccph_sport	   = rxdh->dccph_dport;
	dh->dccph_dport	   = rxdh->dccph_sport;
	dh->dccph_doff	   = dccp_hdr_reset_len / 4;
	dh->dccph_x	   = 1;
922 923
	dccp_hdr_reset(skb)->dccph_reset_code =
				DCCP_SKB_CB(rxskb)->dccpd_reset_code;
924

925 926 927 928 929 930
	/* See "8.3.1. Abnormal Termination" in draft-ietf-dccp-spec-11 */
	seqno = 0;
	if (DCCP_SKB_CB(rxskb)->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ)
		dccp_set_seqno(&seqno, DCCP_SKB_CB(rxskb)->dccpd_ack_seq + 1);

	dccp_hdr_set_seq(dh, seqno);
931 932
	dccp_hdr_set_ack(dccp_hdr_ack_bits(skb),
			 DCCP_SKB_CB(rxskb)->dccpd_seq);
933

934 935
	dh->dccph_checksum = dccp_v4_checksum(skb, rxskb->nh.iph->saddr,
					      rxskb->nh.iph->daddr);
936 937 938

	bh_lock_sock(dccp_ctl_socket->sk);
	err = ip_build_and_send_pkt(skb, dccp_ctl_socket->sk,
939 940
				    rxskb->nh.iph->daddr,
				    rxskb->nh.iph->saddr, NULL);
941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963
	bh_unlock_sock(dccp_ctl_socket->sk);

	if (err == NET_XMIT_CN || err == 0) {
		DCCP_INC_STATS_BH(DCCP_MIB_OUTSEGS);
		DCCP_INC_STATS_BH(DCCP_MIB_OUTRSTS);
	}
out:
	 dst_release(dst);
}

int dccp_v4_do_rcv(struct sock *sk, struct sk_buff *skb)
{
	struct dccp_hdr *dh = dccp_hdr(skb);

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

	/*
	 *  Step 3: Process LISTEN state
	 *     If S.state == LISTEN,
964 965
	 *	  If P.type == Request or P contains a valid Init Cookie
	 *	  	option,
966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981
	 *	     * Must scan the packet's options to check for an Init
	 *		Cookie.  Only the Init Cookie is 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 Cookie
	 *	     Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie
	 *	     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
	 *
982 983
	 * NOTE: the check for the packet types is done in
	 *	 dccp_rcv_state_process
984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008
	 */
	if (sk->sk_state == DCCP_LISTEN) {
		struct sock *nsk = dccp_v4_hnd_req(sk, skb);

		if (nsk == NULL)
			goto discard;

		if (nsk != sk) {
			if (dccp_child_process(sk, nsk, skb))
				goto reset;
			return 0;
		}
	}

	if (dccp_rcv_state_process(sk, skb, dh, skb->len))
		goto reset;
	return 0;

reset:
	dccp_v4_ctl_send_reset(skb);
discard:
	kfree_skb(skb);
	return 0;
}

1009 1010 1011
EXPORT_SYMBOL_GPL(dccp_v4_do_rcv);

int dccp_invalid_packet(struct sk_buff *skb)
1012 1013 1014 1015 1016 1017 1018
{
	const struct dccp_hdr *dh;

	if (skb->pkt_type != PACKET_HOST)
		return 1;

	if (!pskb_may_pull(skb, sizeof(struct dccp_hdr))) {
1019
		LIMIT_NETDEBUG(KERN_WARNING "DCCP: pskb_may_pull failed\n");
1020 1021 1022 1023 1024 1025 1026
		return 1;
	}

	dh = dccp_hdr(skb);

	/* If the packet type is not understood, drop packet and return */
	if (dh->dccph_type >= DCCP_PKT_INVALID) {
1027
		LIMIT_NETDEBUG(KERN_WARNING "DCCP: invalid packet type\n");
1028 1029 1030 1031 1032 1033 1034 1035
		return 1;
	}

	/*
	 * If P.Data Offset is too small for packet type, or too large for
	 * packet, drop packet and return
	 */
	if (dh->dccph_doff < dccp_hdr_len(skb) / sizeof(u32)) {
1036 1037 1038
		LIMIT_NETDEBUG(KERN_WARNING "DCCP: P.Data Offset(%u) "
					    "too small 1\n",
			       dh->dccph_doff);
1039 1040 1041 1042
		return 1;
	}

	if (!pskb_may_pull(skb, dh->dccph_doff * sizeof(u32))) {
1043 1044 1045
		LIMIT_NETDEBUG(KERN_WARNING "DCCP: P.Data Offset(%u) "
					    "too small 2\n",
			       dh->dccph_doff);
1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058
		return 1;
	}

	dh = dccp_hdr(skb);

	/*
	 * If P.type is not Data, Ack, or DataAck and P.X == 0 (the packet
	 * has short sequence numbers), drop packet and return
	 */
	if (dh->dccph_x == 0 &&
	    dh->dccph_type != DCCP_PKT_DATA &&
	    dh->dccph_type != DCCP_PKT_ACK &&
	    dh->dccph_type != DCCP_PKT_DATAACK) {
1059 1060 1061
		LIMIT_NETDEBUG(KERN_WARNING "DCCP: P.type (%s) not Data, Ack "
					    "nor DataAck and P.X == 0\n",
			       dccp_packet_name(dh->dccph_type));
1062 1063 1064 1065 1066 1067
		return 1;
	}

	return 0;
}

1068 1069
EXPORT_SYMBOL_GPL(dccp_invalid_packet);

1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081
/* this is called when real data arrives */
int dccp_v4_rcv(struct sk_buff *skb)
{
	const struct dccp_hdr *dh;
	struct sock *sk;
	int rc;

	/* Step 1: Check header basics: */

	if (dccp_invalid_packet(skb))
		goto discard_it;

1082 1083 1084 1085 1086 1087 1088 1089
	/* If the header checksum is incorrect, drop packet and return */
	if (dccp_v4_verify_checksum(skb, skb->nh.iph->saddr,
				    skb->nh.iph->daddr) < 0) {
		LIMIT_NETDEBUG(KERN_WARNING "%s: incorrect header checksum\n",
			       __FUNCTION__);
		goto discard_it;
	}

1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100
	dh = dccp_hdr(skb);

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

	dccp_pr_debug("%8.8s "
		      "src=%u.%u.%u.%u@%-5d "
		      "dst=%u.%u.%u.%u@%-5d seq=%llu",
		      dccp_packet_name(dh->dccph_type),
		      NIPQUAD(skb->nh.iph->saddr), ntohs(dh->dccph_sport),
		      NIPQUAD(skb->nh.iph->daddr), ntohs(dh->dccph_dport),
1101
		      (unsigned long long) DCCP_SKB_CB(skb)->dccpd_seq);
1102 1103 1104 1105 1106 1107

	if (dccp_packet_without_ack(skb)) {
		DCCP_SKB_CB(skb)->dccpd_ack_seq = DCCP_PKT_WITHOUT_ACK_SEQ;
		dccp_pr_debug_cat("\n");
	} else {
		DCCP_SKB_CB(skb)->dccpd_ack_seq = dccp_hdr_ack_seq(skb);
1108 1109 1110
		dccp_pr_debug_cat(", ack=%llu\n",
				  (unsigned long long)
				  DCCP_SKB_CB(skb)->dccpd_ack_seq);
1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139
	}

	/* Step 2:
	 * 	Look up flow ID in table and get corresponding socket */
	sk = __inet_lookup(&dccp_hashinfo,
			   skb->nh.iph->saddr, dh->dccph_sport,
			   skb->nh.iph->daddr, ntohs(dh->dccph_dport),
			   inet_iif(skb));

	/* 
	 * Step 2:
	 * 	If no socket ...
	 *		Generate Reset(No Connection) unless P.type == Reset
	 *		Drop packet and return
	 */
	if (sk == NULL) {
		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) {
1140 1141 1142
		dccp_pr_debug("sk->sk_state == DCCP_TIME_WAIT: "
			      "do_time_wait\n");
                goto do_time_wait;
1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176
	}

	if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb)) {
		dccp_pr_debug("xfrm4_policy_check failed\n");
		goto discard_and_relse;
	}

        if (sk_filter(sk, skb, 0)) {
		dccp_pr_debug("sk_filter failed\n");
                goto discard_and_relse;
	}

	skb->dev = NULL;

	bh_lock_sock(sk);
	rc = 0;
	if (!sock_owned_by_user(sk))
		rc = dccp_v4_do_rcv(sk, skb);
	else
		sk_add_backlog(sk, skb);
	bh_unlock_sock(sk);

	sock_put(sk);
	return rc;

no_dccp_socket:
	if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb))
		goto discard_it;
	/*
	 * Step 2:
	 *		Generate Reset(No Connection) unless P.type == Reset
	 *		Drop packet and return
	 */
	if (dh->dccph_type != DCCP_PKT_RESET) {
1177 1178
		DCCP_SKB_CB(skb)->dccpd_reset_code =
					DCCP_RESET_CODE_NO_CONNECTION;
1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189
		dccp_v4_ctl_send_reset(skb);
	}

discard_it:
	/* Discard frame. */
	kfree_skb(skb);
	return 0;

discard_and_relse:
	sock_put(sk);
	goto discard_it;
1190 1191 1192 1193

do_time_wait:
	inet_twsk_put((struct inet_timewait_sock *)sk);
	goto no_dccp_socket;
1194 1195
}

1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208
struct inet_connection_sock_af_ops dccp_ipv4_af_ops = {
	.queue_xmit	= ip_queue_xmit,
	.send_check	= dccp_v4_send_check,
	.rebuild_header	= inet_sk_rebuild_header,
	.conn_request	= dccp_v4_conn_request,
	.syn_recv_sock	= dccp_v4_request_recv_sock,
	.net_header_len	= sizeof(struct iphdr),
	.setsockopt	= ip_setsockopt,
	.getsockopt	= ip_getsockopt,
	.addr2sockaddr	= inet_csk_addr2sockaddr,
	.sockaddr_len	= sizeof(struct sockaddr_in),
};

1209
int dccp_v4_init_sock(struct sock *sk)
1210 1211 1212 1213 1214
{
	struct dccp_sock *dp = dccp_sk(sk);
	static int dccp_ctl_socket_init = 1;

	dccp_options_init(&dp->dccps_options);
1215
	do_gettimeofday(&dp->dccps_epoch);
1216 1217

	if (dp->dccps_options.dccpo_send_ack_vector) {
1218 1219 1220
		dp->dccps_hc_rx_ackvec = dccp_ackvec_alloc(DCCP_MAX_ACKVEC_LEN,
							   GFP_KERNEL);
		if (dp->dccps_hc_rx_ackvec == NULL)
1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231
			return -ENOMEM;
	}

	/*
	 * FIXME: We're hardcoding the CCID, and doing this at this point makes
	 * the listening (master) sock get CCID control blocks, which is not
	 * necessary, but for now, to not mess with the test userspace apps,
	 * lets leave it here, later the real solution is to do this in a
	 * setsockopt(CCIDs-I-want/accept). -acme
	 */
	if (likely(!dccp_ctl_socket_init)) {
1232
		dp->dccps_hc_rx_ccid = ccid_init(dp->dccps_options.dccpo_rx_ccid,
1233
						 sk);
1234
		dp->dccps_hc_tx_ccid = ccid_init(dp->dccps_options.dccpo_tx_ccid,
1235
						 sk);
1236 1237 1238 1239
	    	if (dp->dccps_hc_rx_ccid == NULL ||
		    dp->dccps_hc_tx_ccid == NULL) {
			ccid_exit(dp->dccps_hc_rx_ccid, sk);
			ccid_exit(dp->dccps_hc_tx_ccid, sk);
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			if (dp->dccps_options.dccpo_send_ack_vector) {
				dccp_ackvec_free(dp->dccps_hc_rx_ackvec);
				dp->dccps_hc_rx_ackvec = NULL;
			}
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			dp->dccps_hc_rx_ccid = dp->dccps_hc_tx_ccid = NULL;
			return -ENOMEM;
		}
	} else
		dccp_ctl_socket_init = 0;

	dccp_init_xmit_timers(sk);
1251
	inet_csk(sk)->icsk_rto = DCCP_TIMEOUT_INIT;
1252
	sk->sk_state = DCCP_CLOSED;
1253
	sk->sk_write_space = dccp_write_space;
1254
	inet_csk(sk)->icsk_af_ops = &dccp_ipv4_af_ops;
1255 1256
	dp->dccps_mss_cache = 536;
	dp->dccps_role = DCCP_ROLE_UNDEFINED;
1257
	dp->dccps_service = DCCP_SERVICE_INVALID_VALUE;
1258 1259 1260 1261

	return 0;
}

1262 1263 1264
EXPORT_SYMBOL_GPL(dccp_v4_init_sock);

int dccp_v4_destroy_sock(struct sock *sk)
1265 1266 1267 1268
{
	struct dccp_sock *dp = dccp_sk(sk);

	/*
I
Ian McDonald 已提交
1269
	 * DCCP doesn't use sk_write_queue, just sk_send_head
1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280
	 * for retransmissions
	 */
	if (sk->sk_send_head != NULL) {
		kfree_skb(sk->sk_send_head);
		sk->sk_send_head = NULL;
	}

	/* Clean up a referenced DCCP bind bucket. */
	if (inet_csk(sk)->icsk_bind_hash != NULL)
		inet_put_port(&dccp_hashinfo, sk);

J
Jesper Juhl 已提交
1281 1282
	kfree(dp->dccps_service_list);
	dp->dccps_service_list = NULL;
1283

1284 1285
	ccid_hc_rx_exit(dp->dccps_hc_rx_ccid, sk);
	ccid_hc_tx_exit(dp->dccps_hc_tx_ccid, sk);
1286 1287 1288 1289
	if (dp->dccps_options.dccpo_send_ack_vector) {
		dccp_ackvec_free(dp->dccps_hc_rx_ackvec);
		dp->dccps_hc_rx_ackvec = NULL;
	}
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	ccid_exit(dp->dccps_hc_rx_ccid, sk);
	ccid_exit(dp->dccps_hc_tx_ccid, sk);
	dp->dccps_hc_rx_ccid = dp->dccps_hc_tx_ccid = NULL;

	return 0;
}

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EXPORT_SYMBOL_GPL(dccp_v4_destroy_sock);

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static void dccp_v4_reqsk_destructor(struct request_sock *req)
{
	kfree(inet_rsk(req)->opt);
}

static struct request_sock_ops dccp_request_sock_ops = {
	.family		= PF_INET,
	.obj_size	= sizeof(struct dccp_request_sock),
	.rtx_syn_ack	= dccp_v4_send_response,
	.send_ack	= dccp_v4_reqsk_send_ack,
	.destructor	= dccp_v4_reqsk_destructor,
	.send_reset	= dccp_v4_ctl_send_reset,
};

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static struct timewait_sock_ops dccp_timewait_sock_ops = {
	.twsk_obj_size	= sizeof(struct inet_timewait_sock),
};

1317
struct proto dccp_prot = {
1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330
	.name			= "DCCP",
	.owner			= THIS_MODULE,
	.close			= dccp_close,
	.connect		= dccp_v4_connect,
	.disconnect		= dccp_disconnect,
	.ioctl			= dccp_ioctl,
	.init			= dccp_v4_init_sock,
	.setsockopt		= dccp_setsockopt,
	.getsockopt		= dccp_getsockopt,
	.sendmsg		= dccp_sendmsg,
	.recvmsg		= dccp_recvmsg,
	.backlog_rcv		= dccp_v4_do_rcv,
	.hash			= dccp_v4_hash,
1331
	.unhash			= dccp_unhash,
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	.accept			= inet_csk_accept,
	.get_port		= dccp_v4_get_port,
	.shutdown		= dccp_shutdown,
	.destroy		= dccp_v4_destroy_sock,
	.orphan_count		= &dccp_orphan_count,
	.max_header		= MAX_DCCP_HEADER,
	.obj_size		= sizeof(struct dccp_sock),
	.rsk_prot		= &dccp_request_sock_ops,
1340
	.twsk_prot		= &dccp_timewait_sock_ops,
1341
};
1342 1343

EXPORT_SYMBOL_GPL(dccp_prot);