Merge branch 'dccp' of git://eden-feed.erg.abdn.ac.uk/dccp_exp

Conflicts:

	net/dccp/input.c
	net/dccp/options.c

1 files changed, 73 insertions, 91 deletions

diff --git a/net/dccp/input.c b/net/dccp/input.c
index 779d0ed9ae94..df0e6714aa11 100644
--- a/net/dccp/input.c
+++ b/net/dccp/input.c
@@ -159,13 +159,15 @@ static void dccp_rcv_reset(struct sock *sk, struct sk_buff *skb)
 	dccp_time_wait(sk, DCCP_TIME_WAIT, 0);
 }
 
-static void dccp_event_ack_recv(struct sock *sk, struct sk_buff *skb)
+static void dccp_handle_ackvec_processing(struct sock *sk, struct sk_buff *skb)
 {
-	struct dccp_sock *dp = dccp_sk(sk);
+	struct dccp_ackvec *av = dccp_sk(sk)->dccps_hc_rx_ackvec;
 
-	if (dccp_msk(sk)->dccpms_send_ack_vector)
-		dccp_ackvec_check_rcv_ackno(dp->dccps_hc_rx_ackvec, sk,
-					    DCCP_SKB_CB(skb)->dccpd_ack_seq);
+	if (av == NULL)
+		return;
+	if (DCCP_SKB_CB(skb)->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ)
+		dccp_ackvec_clear_state(av, DCCP_SKB_CB(skb)->dccpd_ack_seq);
+	dccp_ackvec_input(av, skb);
 }
 
 static void dccp_deliver_input_to_ccids(struct sock *sk, struct sk_buff *skb)
@@ -364,22 +366,13 @@ discard:
 int dccp_rcv_established(struct sock *sk, struct sk_buff *skb,
 			 const struct dccp_hdr *dh, const unsigned len)
 {
-	struct dccp_sock *dp = dccp_sk(sk);
-
 	if (dccp_check_seqno(sk, skb))
 		goto discard;
 
 	if (dccp_parse_options(sk, NULL, skb))
 		return 1;
 
-	if (DCCP_SKB_CB(skb)->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ)
-		dccp_event_ack_recv(sk, skb);
-
-	if (dccp_msk(sk)->dccpms_send_ack_vector &&
-	    dccp_ackvec_add(dp->dccps_hc_rx_ackvec, sk,
-			    DCCP_SKB_CB(skb)->dccpd_seq,
-			    DCCP_ACKVEC_STATE_RECEIVED))
-		goto discard;
+	dccp_handle_ackvec_processing(sk, skb);
 	dccp_deliver_input_to_ccids(sk, skb);
 
 	return __dccp_rcv_established(sk, skb, dh, len);
@@ -421,40 +414,33 @@ static int dccp_rcv_request_sent_state_process(struct sock *sk,
 			goto out_invalid_packet;
 		}
 
+		/*
+		 * If option processing (Step 8) failed, return 1 here so that
+		 * dccp_v4_do_rcv() sends a Reset. The Reset code depends on
+		 * the option type and is set in dccp_parse_options().
+		 */
 		if (dccp_parse_options(sk, NULL, skb))
-			goto out_invalid_packet;
+			return 1;
 
 		/* Obtain usec RTT sample from SYN exchange (used by CCID 3) */
 		if (likely(dp->dccps_options_received.dccpor_timestamp_echo))
 			dp->dccps_syn_rtt = dccp_sample_rtt(sk, 10 * (tstamp -
 			    dp->dccps_options_received.dccpor_timestamp_echo));
 
-		if (dccp_msk(sk)->dccpms_send_ack_vector &&
-		    dccp_ackvec_add(dp->dccps_hc_rx_ackvec, sk,
-				    DCCP_SKB_CB(skb)->dccpd_seq,
-				    DCCP_ACKVEC_STATE_RECEIVED))
-			goto out_invalid_packet; /* FIXME: change error code */
-
 		/* Stop the REQUEST timer */
 		inet_csk_clear_xmit_timer(sk, ICSK_TIME_RETRANS);
 		WARN_ON(sk->sk_send_head == NULL);
 		kfree_skb(sk->sk_send_head);
 		sk->sk_send_head = NULL;
 
-		dp->dccps_isr = DCCP_SKB_CB(skb)->dccpd_seq;
-		dccp_update_gsr(sk, dp->dccps_isr);
 		/*
-		 * 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.
-		 *
-		 * AWL was adjusted in dccp_v4_connect -acme
+		 * Set ISR, GSR from packet. ISS was set in dccp_v{4,6}_connect
+		 * and GSS in dccp_transmit_skb(). Setting AWL/AWH and SWL/SWH
+		 * is done as part of activating the feature values below, since
+		 * these settings depend on the local/remote Sequence Window
+		 * features, which were undefined or not confirmed until now.
 		 */
-		dccp_set_seqno(&dp->dccps_swl,
-			       max48(dp->dccps_swl, dp->dccps_isr));
+		dp->dccps_gsr = dp->dccps_isr = DCCP_SKB_CB(skb)->dccpd_seq;
 
 		dccp_sync_mss(sk, icsk->icsk_pmtu_cookie);
 
@@ -475,6 +461,15 @@ static int dccp_rcv_request_sent_state_process(struct sock *sk,
 		 */
 		dccp_set_state(sk, DCCP_PARTOPEN);
 
+		/*
+		 * If feature negotiation was successful, activate features now;
+		 * an activation failure means that this host could not activate
+		 * one ore more features (e.g. insufficient memory), which would
+		 * leave at least one feature in an undefined state.
+		 */
+		if (dccp_feat_activate_values(sk, &dp->dccps_featneg))
+			goto unable_to_proceed;
+
 		/* Make sure socket is routed, for correct metrics. */
 		icsk->icsk_af_ops->rebuild_header(sk);
 
@@ -509,6 +504,16 @@ out_invalid_packet:
 	/* dccp_v4_do_rcv will send a reset */
 	DCCP_SKB_CB(skb)->dccpd_reset_code = DCCP_RESET_CODE_PACKET_ERROR;
 	return 1;
+
+unable_to_proceed:
+	DCCP_SKB_CB(skb)->dccpd_reset_code = DCCP_RESET_CODE_ABORTED;
+	/*
+	 * We mark this socket as no longer usable, so that the loop in
+	 * dccp_sendmsg() terminates and the application gets notified.
+	 */
+	dccp_set_state(sk, DCCP_CLOSED);
+	sk->sk_err = ECOMM;
+	return 1;
 }
 
 static int dccp_rcv_respond_partopen_state_process(struct sock *sk,
@@ -590,8 +595,6 @@ int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
 			if (inet_csk(sk)->icsk_af_ops->conn_request(sk,
 								    skb) < 0)
 				return 1;
-
-			/* FIXME: do congestion control initialization */
 			goto discard;
 		}
 		if (dh->dccph_type == DCCP_PKT_RESET)
@@ -600,30 +603,36 @@ int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
 		/* Caller (dccp_v4_do_rcv) will send Reset */
 		dcb->dccpd_reset_code = DCCP_RESET_CODE_NO_CONNECTION;
 		return 1;
+	} else if (sk->sk_state == DCCP_CLOSED) {
+		dcb->dccpd_reset_code = DCCP_RESET_CODE_NO_CONNECTION;
+		return 1;
 	}
 
-	if (sk->sk_state != DCCP_REQUESTING) {
-		if (dccp_check_seqno(sk, skb))
-			goto discard;
-
-		/*
-		 * Step 8: Process options and mark acknowledgeable
-		 */
-		if (dccp_parse_options(sk, NULL, skb))
-			return 1;
-
-		if (dcb->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ)
-			dccp_event_ack_recv(sk, skb);
-
-		if (dccp_msk(sk)->dccpms_send_ack_vector &&
-		    dccp_ackvec_add(dp->dccps_hc_rx_ackvec, sk,
-				    DCCP_SKB_CB(skb)->dccpd_seq,
-				    DCCP_ACKVEC_STATE_RECEIVED))
-			goto discard;
+	/* Step 6: Check sequence numbers (omitted in LISTEN/REQUEST state) */
+	if (sk->sk_state != DCCP_REQUESTING && dccp_check_seqno(sk, skb))
+		goto discard;
 
-		dccp_deliver_input_to_ccids(sk, skb);
+	/*
+	 *   Step 7: Check for unexpected packet types
+	 *      If (S.is_server and P.type == Response)
+	 *	    or (S.is_client and P.type == Request)
+	 *	    or (S.state == RESPOND and P.type == Data),
+	 *	  Send Sync packet acknowledging P.seqno
+	 *	  Drop packet and return
+	 */
+	if ((dp->dccps_role != DCCP_ROLE_CLIENT &&
+	     dh->dccph_type == DCCP_PKT_RESPONSE) ||
+	    (dp->dccps_role == DCCP_ROLE_CLIENT &&
+	     dh->dccph_type == DCCP_PKT_REQUEST) ||
+	    (sk->sk_state == DCCP_RESPOND && dh->dccph_type == DCCP_PKT_DATA)) {
+		dccp_send_sync(sk, dcb->dccpd_seq, DCCP_PKT_SYNC);
+		goto discard;
 	}
 
+	/*  Step 8: Process options */
+	if (dccp_parse_options(sk, NULL, skb))
+		return 1;
+
 	/*
 	 *  Step 9: Process Reset
 	 *	If P.type == Reset,
@@ -631,44 +640,22 @@ int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
 	 *		S.state := TIMEWAIT
 	 *		Set TIMEWAIT timer
 	 *		Drop packet and return
-	*/
+	 */
 	if (dh->dccph_type == DCCP_PKT_RESET) {
 		dccp_rcv_reset(sk, skb);
 		return 0;
-		/*
-		 *   Step 7: Check for unexpected packet types
-		 *      If (S.is_server and P.type == Response)
-		 *	    or (S.is_client and P.type == Request)
-		 *	    or (S.state == RESPOND and P.type == Data),
-		 *	  Send Sync packet acknowledging P.seqno
-		 *	  Drop packet and return
-		 */
-	} else if ((dp->dccps_role != DCCP_ROLE_CLIENT &&
-		    dh->dccph_type == DCCP_PKT_RESPONSE) ||
-		    (dp->dccps_role == DCCP_ROLE_CLIENT &&
-		     dh->dccph_type == DCCP_PKT_REQUEST) ||
-		    (sk->sk_state == DCCP_RESPOND &&
-		     dh->dccph_type == DCCP_PKT_DATA)) {
-		dccp_send_sync(sk, dcb->dccpd_seq, DCCP_PKT_SYNC);
-		goto discard;
-	} else if (dh->dccph_type == DCCP_PKT_CLOSEREQ) {
+	} else if (dh->dccph_type == DCCP_PKT_CLOSEREQ) {	/* Step 13 */
 		if (dccp_rcv_closereq(sk, skb))
 			return 0;
 		goto discard;
-	} else if (dh->dccph_type == DCCP_PKT_CLOSE) {
+	} else if (dh->dccph_type == DCCP_PKT_CLOSE) {		/* Step 14 */
 		if (dccp_rcv_close(sk, skb))
 			return 0;
 		goto discard;
 	}
 
 	switch (sk->sk_state) {
-	case DCCP_CLOSED:
-		dcb->dccpd_reset_code = DCCP_RESET_CODE_NO_CONNECTION;
-		return 1;
-
 	case DCCP_REQUESTING:
-		/* FIXME: do congestion control initialization */
-
 		queued = dccp_rcv_request_sent_state_process(sk, skb, dh, len);
 		if (queued >= 0)
 			return queued;
@@ -676,8 +663,12 @@ int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
 		__kfree_skb(skb);
 		return 0;
 
-	case DCCP_RESPOND:
 	case DCCP_PARTOPEN:
+		/* Step 8: if using Ack Vectors, mark packet acknowledgeable */
+		dccp_handle_ackvec_processing(sk, skb);
+		dccp_deliver_input_to_ccids(sk, skb);
+		/* fall through */
+	case DCCP_RESPOND:
 		queued = dccp_rcv_respond_partopen_state_process(sk, skb,
 								 dh, len);
 		break;
@@ -716,16 +707,7 @@ u32 dccp_sample_rtt(struct sock *sk, long delta)
 	/* dccpor_elapsed_time is either zeroed out or set and > 0 */
 	delta -= dccp_sk(sk)->dccps_options_received.dccpor_elapsed_time * 10;
 
-	if (unlikely(delta <= 0)) {
-		DCCP_WARN("unusable RTT sample %ld, using min\n", delta);
-		return DCCP_SANE_RTT_MIN;
-	}
-	if (unlikely(delta > DCCP_SANE_RTT_MAX)) {
-		DCCP_WARN("RTT sample %ld too large, using max\n", delta);
-		return DCCP_SANE_RTT_MAX;
-	}
-
-	return delta;
+	return dccp_sane_rtt(delta);
 }
 
 EXPORT_SYMBOL_GPL(dccp_sample_rtt);