示例#1
0
文件: output.c 项目: 274914765/C
/*
 * Do all connect socket setups that can be done AF independent.
 */
static inline void dccp_connect_init(struct sock *sk)
{
    struct dccp_sock *dp = dccp_sk(sk);
    struct dst_entry *dst = __sk_dst_get(sk);
    struct inet_connection_sock *icsk = inet_csk(sk);

    sk->sk_err = 0;
    sock_reset_flag(sk, SOCK_DONE);

    dccp_sync_mss(sk, dst_mtu(dst));

    /*
     * SWL and AWL are initially adjusted so that they are not less than
     * the initial Sequence Numbers received and sent, respectively:
     *    SWL := max(GSR + 1 - floor(W/4), ISR),
     *    AWL := max(GSS - W' + 1, ISS).
     * These adjustments MUST be applied only at the beginning of the
     * connection.
     */
    dccp_update_gss(sk, dp->dccps_iss);
    dccp_set_seqno(&dp->dccps_awl, max48(dp->dccps_awl, dp->dccps_iss));

    /* S.GAR - greatest valid acknowledgement number received on a non-Sync;
     *         initialized to S.ISS (sec. 8.5)                            */
    dp->dccps_gar = dp->dccps_iss;

    icsk->icsk_retransmits = 0;
}
示例#2
0
/*
 * Do all connect socket setups that can be done AF independent.
 */
static inline void dccp_connect_init(struct sock *sk)
{
	struct dccp_sock *dp = dccp_sk(sk);
	struct dst_entry *dst = __sk_dst_get(sk);
	struct inet_connection_sock *icsk = inet_csk(sk);

	sk->sk_err = 0;
	sock_reset_flag(sk, SOCK_DONE);
	
	dccp_sync_mss(sk, dst_mtu(dst));

	dccp_update_gss(sk, dp->dccps_iss);
 	/*
	 * SWL and AWL are initially adjusted so that they are not less than
	 * the initial Sequence Numbers received and sent, respectively:
	 *	SWL := max(GSR + 1 - floor(W/4), ISR),
	 *	AWL := max(GSS - W' + 1, ISS).
	 * These adjustments MUST be applied only at the beginning of the
	 * connection.
 	 */
	dccp_set_seqno(&dp->dccps_awl, max48(dp->dccps_awl, dp->dccps_iss));

	icsk->icsk_retransmits = 0;
	init_timer(&dp->dccps_xmit_timer);
	dp->dccps_xmit_timer.data = (unsigned long)sk;
	dp->dccps_xmit_timer.function = dccp_write_xmit_timer;
}
示例#3
0
static int dccp_hdlr_seq_win(struct sock *sk, u64 seq_win, bool rx)
{
	struct dccp_sock *dp = dccp_sk(sk);

	if (rx) {
		dp->dccps_r_seq_win = seq_win;
		/* propagate changes to update SWL/SWH */
		dccp_update_gsr(sk, dp->dccps_gsr);
	} else {
		dp->dccps_l_seq_win = seq_win;
		/* propagate changes to update AWL */
		dccp_update_gss(sk, dp->dccps_gss);
	}
	return 0;
}
示例#4
0
/*
 * All SKB's seen here are completely headerless. It is our
 * job to build the DCCP header, and pass the packet down to
 * IP so it can do the same plus pass the packet off to the
 * device.
 */
static int dccp_transmit_skb(struct sock *sk, struct sk_buff *skb)
{
	if (likely(skb != NULL)) {
		struct inet_sock *inet = inet_sk(sk);
		const struct inet_connection_sock *icsk = inet_csk(sk);
		struct dccp_sock *dp = dccp_sk(sk);
		struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb);
		struct dccp_hdr *dh;
		/* XXX For now we're using only 48 bits sequence numbers */
		const u32 dccp_header_size = sizeof(*dh) +
					     sizeof(struct dccp_hdr_ext) +
					  dccp_packet_hdr_len(dcb->dccpd_type);
		int err, set_ack = 1;
		u64 ackno = dp->dccps_gsr;
		/*
		 * Increment GSS here already in case the option code needs it.
		 * Update GSS for real only if option processing below succeeds.
		 */
		dcb->dccpd_seq = ADD48(dp->dccps_gss, 1);

		switch (dcb->dccpd_type) {
		case DCCP_PKT_DATA:
			set_ack = 0;
			/* fall through */
		case DCCP_PKT_DATAACK:
		case DCCP_PKT_RESET:
			break;

		case DCCP_PKT_REQUEST:
			set_ack = 0;
			/* Use ISS on the first (non-retransmitted) Request. */
			if (icsk->icsk_retransmits == 0)
				dcb->dccpd_seq = dp->dccps_iss;
			/* fall through */

		case DCCP_PKT_SYNC:
		case DCCP_PKT_SYNCACK:
			ackno = dcb->dccpd_ack_seq;
			/* fall through */
		default:
			/*
			 * Set owner/destructor: some skbs are allocated via
			 * alloc_skb (e.g. when retransmission may happen).
			 * Only Data, DataAck, and Reset packets should come
			 * through here with skb->sk set.
			 */
			WARN_ON(skb->sk);
			skb_set_owner_w(skb, sk);
			break;
		}

		if (dccp_insert_options(sk, skb)) {
			kfree_skb(skb);
			return -EPROTO;
		}


		/* Build DCCP header and checksum it. */
		dh = dccp_zeroed_hdr(skb, dccp_header_size);
		dh->dccph_type	= dcb->dccpd_type;
		dh->dccph_sport	= inet->inet_sport;
		dh->dccph_dport	= inet->inet_dport;
		dh->dccph_doff	= (dccp_header_size + dcb->dccpd_opt_len) / 4;
		dh->dccph_ccval	= dcb->dccpd_ccval;
		dh->dccph_cscov = dp->dccps_pcslen;
		/* XXX For now we're using only 48 bits sequence numbers */
		dh->dccph_x	= 1;

		dccp_update_gss(sk, dcb->dccpd_seq);
		dccp_hdr_set_seq(dh, dp->dccps_gss);
		if (set_ack)
			dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), ackno);

		switch (dcb->dccpd_type) {
		case DCCP_PKT_REQUEST:
			dccp_hdr_request(skb)->dccph_req_service =
							dp->dccps_service;
			/*
			 * Limit Ack window to ISS <= P.ackno <= GSS, so that
			 * only Responses to Requests we sent are considered.
			 */
			dp->dccps_awl = dp->dccps_iss;
			break;
		case DCCP_PKT_RESET:
			dccp_hdr_reset(skb)->dccph_reset_code =
							dcb->dccpd_reset_code;
			break;
		}

		icsk->icsk_af_ops->send_check(sk, skb);

		if (set_ack)
			dccp_event_ack_sent(sk);

		DCCP_INC_STATS(DCCP_MIB_OUTSEGS);

		err = icsk->icsk_af_ops->queue_xmit(skb, &inet->cork.fl);
		return net_xmit_eval(err);
	}
	return -ENOBUFS;
}
示例#5
0
static int dccp_transmit_skb(struct sock *sk, struct sk_buff *skb)
{
	if (likely(skb != NULL)) {
		const struct inet_sock *inet = inet_sk(sk);
		const struct inet_connection_sock *icsk = inet_csk(sk);
		struct dccp_sock *dp = dccp_sk(sk);
		struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb);
		struct dccp_hdr *dh;
		
		const u32 dccp_header_size = sizeof(*dh) +
					     sizeof(struct dccp_hdr_ext) +
					  dccp_packet_hdr_len(dcb->dccpd_type);
		int err, set_ack = 1;
		u64 ackno = dp->dccps_gsr;
		
		dcb->dccpd_seq = ADD48(dp->dccps_gss, 1);

		switch (dcb->dccpd_type) {
		case DCCP_PKT_DATA:
			set_ack = 0;
			
		case DCCP_PKT_DATAACK:
		case DCCP_PKT_RESET:
			break;

		case DCCP_PKT_REQUEST:
			set_ack = 0;
			
			if (icsk->icsk_retransmits == 0)
				dcb->dccpd_seq = dp->dccps_iss;
			

		case DCCP_PKT_SYNC:
		case DCCP_PKT_SYNCACK:
			ackno = dcb->dccpd_ack_seq;
			
		default:
			
			WARN_ON(skb->sk);
			skb_set_owner_w(skb, sk);
			break;
		}

		if (dccp_insert_options(sk, skb)) {
			kfree_skb(skb);
			return -EPROTO;
		}


		
		dh = dccp_zeroed_hdr(skb, dccp_header_size);
		dh->dccph_type	= dcb->dccpd_type;
		dh->dccph_sport	= inet->sport;
		dh->dccph_dport	= inet->dport;
		dh->dccph_doff	= (dccp_header_size + dcb->dccpd_opt_len) / 4;
		dh->dccph_ccval	= dcb->dccpd_ccval;
		dh->dccph_cscov = dp->dccps_pcslen;
		
		dh->dccph_x	= 1;

		dccp_update_gss(sk, dcb->dccpd_seq);
		dccp_hdr_set_seq(dh, dp->dccps_gss);
		if (set_ack)
			dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), ackno);

		switch (dcb->dccpd_type) {
		case DCCP_PKT_REQUEST:
			dccp_hdr_request(skb)->dccph_req_service =
							dp->dccps_service;
			
			dp->dccps_awl = dp->dccps_iss;
			break;
		case DCCP_PKT_RESET:
			dccp_hdr_reset(skb)->dccph_reset_code =
							dcb->dccpd_reset_code;
			break;
		}

		icsk->icsk_af_ops->send_check(sk, 0, skb);

		if (set_ack)
			dccp_event_ack_sent(sk);

		DCCP_INC_STATS(DCCP_MIB_OUTSEGS);

		err = icsk->icsk_af_ops->queue_xmit(skb, 0);
		return net_xmit_eval(err);
	}
	return -ENOBUFS;
}
示例#6
0
int dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
{
	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;

	if (dccp_service_not_initialized(sk))
		return -EPROTO;

	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;

	inet_csk(sk)->icsk_ext_hdr_len = 0;
	if (inet->opt != NULL)
		inet_csk(sk)->icsk_ext_hdr_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 = inet_hash_connect(&dccp_death_row, sk);
	if (err != 0)
		goto failure;

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