static void dccp_rcv_close(struct sock *sk, struct sk_buff *skb)
{
- switch (sk->sk_state) {
- case DCCP_PARTOPEN:
- case DCCP_OPEN:
- dccp_v4_send_reset(sk, DCCP_RESET_CODE_CLOSED);
- dccp_fin(sk, skb);
- dccp_set_state(sk, DCCP_CLOSED);
- break;
- }
+ dccp_v4_send_reset(sk, DCCP_RESET_CODE_CLOSED);
+ dccp_fin(sk, skb);
+ dccp_set_state(sk, DCCP_CLOSED);
+ sk_wake_async(sk, 1, POLL_HUP);
}
static void dccp_rcv_closereq(struct sock *sk, struct sk_buff *skb)
* Drop packet and return
*/
if (dccp_sk(sk)->dccps_role != DCCP_ROLE_CLIENT) {
- dccp_send_sync(sk, DCCP_SKB_CB(skb)->dccpd_seq);
+ dccp_send_sync(sk, DCCP_SKB_CB(skb)->dccpd_seq, DCCP_PKT_SYNC);
return;
}
- switch (sk->sk_state) {
- case DCCP_PARTOPEN:
- case DCCP_OPEN:
- dccp_set_state(sk, DCCP_CLOSING);
- dccp_send_close(sk);
- break;
- }
+ dccp_set_state(sk, DCCP_CLOSING);
+ dccp_send_close(sk, 0);
}
static inline void dccp_event_ack_recv(struct sock *sk, struct sk_buff *skb)
{
const struct dccp_hdr *dh = dccp_hdr(skb);
struct dccp_sock *dp = dccp_sk(sk);
- u64 lswl = dp->dccps_swl;
- u64 lawl = dp->dccps_awl;
+ u64 lswl, lawl;
/*
* Step 5: Prepare sequence numbers for Sync
*/
if (dh->dccph_type == DCCP_PKT_SYNC ||
dh->dccph_type == DCCP_PKT_SYNCACK) {
- if (between48(DCCP_SKB_CB(skb)->dccpd_ack_seq, dp->dccps_awl, dp->dccps_awh) &&
+ if (between48(DCCP_SKB_CB(skb)->dccpd_ack_seq,
+ dp->dccps_awl, dp->dccps_awh) &&
!before48(DCCP_SKB_CB(skb)->dccpd_seq, dp->dccps_swl))
dccp_update_gsr(sk, DCCP_SKB_CB(skb)->dccpd_seq);
else
return -1;
+ }
+
/*
* Step 6: Check sequence numbers
* Let LSWL = S.SWL and LAWL = S.AWL
* Send Sync packet acknowledging P.seqno
* Drop packet and return
*/
- } else if (dh->dccph_type == DCCP_PKT_CLOSEREQ ||
- dh->dccph_type == DCCP_PKT_CLOSE ||
- dh->dccph_type == DCCP_PKT_RESET) {
+ lswl = dp->dccps_swl;
+ lawl = dp->dccps_awl;
+
+ if (dh->dccph_type == DCCP_PKT_CLOSEREQ ||
+ dh->dccph_type == DCCP_PKT_CLOSE ||
+ dh->dccph_type == DCCP_PKT_RESET) {
lswl = dp->dccps_gsr;
dccp_inc_seqno(&lswl);
lawl = dp->dccps_gar;
if (between48(DCCP_SKB_CB(skb)->dccpd_seq, lswl, dp->dccps_swh) &&
(DCCP_SKB_CB(skb)->dccpd_ack_seq == DCCP_PKT_WITHOUT_ACK_SEQ ||
- between48(DCCP_SKB_CB(skb)->dccpd_ack_seq, lawl, dp->dccps_awh))) {
+ between48(DCCP_SKB_CB(skb)->dccpd_ack_seq,
+ lawl, dp->dccps_awh))) {
dccp_update_gsr(sk, DCCP_SKB_CB(skb)->dccpd_seq);
if (dh->dccph_type != DCCP_PKT_SYNC &&
- DCCP_SKB_CB(skb)->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ)
+ (DCCP_SKB_CB(skb)->dccpd_ack_seq !=
+ DCCP_PKT_WITHOUT_ACK_SEQ))
dp->dccps_gar = DCCP_SKB_CB(skb)->dccpd_ack_seq;
} else {
- dccp_pr_debug("Step 6 failed, sending SYNC...\n");
- dccp_send_sync(sk, DCCP_SKB_CB(skb)->dccpd_seq);
+ LIMIT_NETDEBUG(KERN_WARNING "DCCP: Step 6 failed for %s packet, "
+ "(LSWL(%llu) <= P.seqno(%llu) <= S.SWH(%llu)) and "
+ "(P.ackno %s or LAWL(%llu) <= P.ackno(%llu) <= S.AWH(%llu), "
+ "sending SYNC...\n",
+ dccp_packet_name(dh->dccph_type),
+ (unsigned long long) lswl,
+ (unsigned long long)
+ DCCP_SKB_CB(skb)->dccpd_seq,
+ (unsigned long long) dp->dccps_swh,
+ (DCCP_SKB_CB(skb)->dccpd_ack_seq ==
+ DCCP_PKT_WITHOUT_ACK_SEQ) ? "doesn't exist" : "exists",
+ (unsigned long long) lawl,
+ (unsigned long long)
+ DCCP_SKB_CB(skb)->dccpd_ack_seq,
+ (unsigned long long) dp->dccps_awh);
+ dccp_send_sync(sk, DCCP_SKB_CB(skb)->dccpd_seq, DCCP_PKT_SYNC);
return -1;
}
if (dccp_ackpkts_add(dp->dccps_hc_rx_ackpkts,
DCCP_SKB_CB(skb)->dccpd_seq,
DCCP_ACKPKTS_STATE_RECEIVED)) {
- LIMIT_NETDEBUG(pr_info("DCCP: acknowledgeable packets buffer full!\n"));
+ LIMIT_NETDEBUG(KERN_WARNING "DCCP: acknowledgeable "
+ "packets buffer full!\n");
ap->dccpap_ack_seqno = DCCP_MAX_SEQNO + 1;
inet_csk_schedule_ack(sk);
- inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK, TCP_DELACK_MIN, TCP_RTO_MAX);
+ inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK,
+ TCP_DELACK_MIN,
+ DCCP_RTO_MAX);
goto discard;
}
*/
if (!inet_csk_ack_scheduled(sk)) {
inet_csk_schedule_ack(sk);
- inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK, 5 * HZ, TCP_RTO_MAX);
+ inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK, 5 * HZ,
+ DCCP_RTO_MAX);
}
}
case DCCP_PKT_DATAACK:
case DCCP_PKT_DATA:
/*
- * FIXME: check if sk_receive_queue is full, schedule DATA_DROPPED option
- * if it is.
+ * FIXME: check if sk_receive_queue is full, schedule DATA_DROPPED
+ * option if it is.
*/
__skb_pull(skb, dh->dccph_doff * 4);
__skb_queue_tail(&sk->sk_receive_queue, skb);
check_seq:
if (!before48(DCCP_SKB_CB(skb)->dccpd_seq, dp->dccps_osr)) {
send_sync:
- dccp_send_sync(sk, DCCP_SKB_CB(skb)->dccpd_seq);
+ dccp_send_sync(sk, DCCP_SKB_CB(skb)->dccpd_seq,
+ DCCP_PKT_SYNC);
}
break;
+ case DCCP_PKT_SYNC:
+ dccp_send_sync(sk, DCCP_SKB_CB(skb)->dccpd_seq,
+ DCCP_PKT_SYNCACK);
+ /*
+ * From the draft:
+ *
+ * As with DCCP-Ack packets, DCCP-Sync and DCCP-SyncAck packets
+ * MAY have non-zero-length application data areas, whose
+ * contents * receivers MUST ignore.
+ */
+ goto discard;
}
DCCP_INC_STATS_BH(DCCP_MIB_INERRS);
__kfree_skb(sk->sk_send_head);
sk->sk_send_head = NULL;
- if (!between48(DCCP_SKB_CB(skb)->dccpd_ack_seq, dp->dccps_awl, dp->dccps_awh)) {
- dccp_pr_debug("invalid ackno: S.AWL=%llu, P.ackno=%llu, S.AWH=%llu \n",
- dp->dccps_awl, DCCP_SKB_CB(skb)->dccpd_ack_seq, dp->dccps_awh);
+ if (!between48(DCCP_SKB_CB(skb)->dccpd_ack_seq,
+ dp->dccps_awl, dp->dccps_awh)) {
+ dccp_pr_debug("invalid ackno: S.AWL=%llu, "
+ "P.ackno=%llu, S.AWH=%llu \n",
+ (unsigned long long)dp->dccps_awl,
+ (unsigned long long)DCCP_SKB_CB(skb)->dccpd_ack_seq,
+ (unsigned long long)dp->dccps_awh);
goto out_invalid_packet;
}
dp->dccps_isr = DCCP_SKB_CB(skb)->dccpd_seq;
- dccp_update_gsr(sk, 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
+ */
+ dccp_set_seqno(&dp->dccps_swl,
+ max48(dp->dccps_swl, dp->dccps_isr));
if (ccid_hc_rx_init(dp->dccps_hc_rx_ccid, sk) != 0 ||
ccid_hc_tx_init(dp->dccps_hc_tx_ccid, sk) != 0) {
/*
* Step 10: Process REQUEST state (second part)
* If S.state == REQUEST,
- * / * If we get here, P is a valid Response from the server (see
- * Step 4), and we should move to PARTOPEN state. PARTOPEN
- * means send an Ack, don't send Data packets, retransmit
- * Acks periodically, and always include any Init Cookie from
- * the Response * /
+ * / * If we get here, P is a valid Response from the
+ * server (see Step 4), and we should move to
+ * PARTOPEN state. PARTOPEN means send an Ack,
+ * don't send Data packets, retransmit Acks
+ * periodically, and always include any Init Cookie
+ * from the Response * /
* S.state := PARTOPEN
* Set PARTOPEN timer
* Continue with S.state == PARTOPEN
- * / * Step 12 will send the Ack completing the three-way
- * handshake * /
+ * / * Step 12 will send the Ack completing the
+ * three-way handshake * /
*/
dccp_set_state(sk, DCCP_PARTOPEN);
out_invalid_packet:
return 1; /* dccp_v4_do_rcv will send a reset, but...
- FIXME: the reset code should be DCCP_RESET_CODE_PACKET_ERROR */
+ FIXME: the reset code should be
+ DCCP_RESET_CODE_PACKET_ERROR */
}
static int dccp_rcv_respond_partopen_state_process(struct sock *sk,
case DCCP_PKT_DATAACK:
case DCCP_PKT_ACK:
/*
- * FIXME: we should be reseting the PARTOPEN (DELACK) timer here,
- * but only if we haven't used the DELACK timer for something else,
- * like sending a delayed ack for a TIMESTAMP echo, etc, for now
- * were not clearing it, sending an extra ACK when there is nothing
- * else to do in DELACK is not a big deal after all.
+ * FIXME: we should be reseting the PARTOPEN (DELACK) timer
+ * here but only if we haven't used the DELACK timer for
+ * something else, like sending a delayed ack for a TIMESTAMP
+ * echo, etc, for now were not clearing it, sending an extra
+ * ACK when there is nothing else to do in DELACK is not a big
+ * deal after all.
*/
/* Stop the PARTOPEN timer */
if (dh->dccph_type == DCCP_PKT_DATAACK) {
dccp_rcv_established(sk, skb, dh, len);
- queued = 1; /* packet was queued (by dccp_rcv_established) */
+ queued = 1; /* packet was queued
+ (by dccp_rcv_established) */
}
break;
}
const int old_state = sk->sk_state;
int queued = 0;
- if (sk->sk_state != DCCP_LISTEN && sk->sk_state != DCCP_REQUESTING) {
+ /*
+ * Step 3: Process LISTEN state
+ * (Continuing from dccp_v4_do_rcv and dccp_v6_do_rcv)
+ *
+ * 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 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
+ *
+ * NOTE: the check for the packet types is done in
+ * dccp_rcv_state_process
+ */
+ if (sk->sk_state == DCCP_LISTEN) {
+ if (dh->dccph_type == DCCP_PKT_REQUEST) {
+ if (dccp_v4_conn_request(sk, skb) < 0)
+ return 1;
+
+ /* FIXME: do congestion control initialization */
+ goto discard;
+ }
+ if (dh->dccph_type == DCCP_PKT_RESET)
+ goto discard;
+
+ /* Caller (dccp_v4_do_rcv) will send Reset(No Connection)*/
+ return 1;
+ }
+
+ if (sk->sk_state != DCCP_REQUESTING) {
if (dccp_check_seqno(sk, skb))
goto discard;
if (dccp_parse_options(sk, skb))
goto discard;
- if (DCCP_SKB_CB(skb)->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ)
+ if (DCCP_SKB_CB(skb)->dccpd_ack_seq !=
+ DCCP_PKT_WITHOUT_ACK_SEQ)
dccp_event_ack_recv(sk, skb);
ccid_hc_rx_packet_recv(dp->dccps_hc_rx_ccid, sk, skb);
DCCP_ACKPKTS_STATE_RECEIVED))
goto discard;
/*
- * FIXME: this activation is probably wrong, have to study more
- * TCP delack machinery and how it fits into DCCP draft, but
- * for now it kinda "works" 8)
+ * FIXME: this activation is probably wrong, have to
+ * study more TCP delack machinery and how it fits into
+ * DCCP draft, but for now it kinda "works" 8)
*/
- if (dp->dccps_hc_rx_ackpkts->dccpap_ack_seqno == DCCP_MAX_SEQNO + 1 &&
+ if ((dp->dccps_hc_rx_ackpkts->dccpap_ack_seqno ==
+ DCCP_MAX_SEQNO + 1) &&
!inet_csk_ack_scheduled(sk)) {
inet_csk_schedule_ack(sk);
- inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK, TCP_DELACK_MIN, TCP_RTO_MAX);
+ inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK,
+ TCP_DELACK_MIN,
+ DCCP_RTO_MAX);
}
}
}
* Drop packet and return
*/
if (dh->dccph_type == DCCP_PKT_RESET) {
- /* Queue the equivalent of TCP fin so that dccp_recvmsg exits the loop */
+ /*
+ * Queue the equivalent of TCP fin so that dccp_recvmsg
+ * exits the loop
+ */
dccp_fin(sk, skb);
dccp_time_wait(sk, DCCP_TIME_WAIT, 0);
return 0;
* Drop packet and return
*/
} else if ((dp->dccps_role != DCCP_ROLE_CLIENT &&
- (dh->dccph_type == DCCP_PKT_RESPONSE || dh->dccph_type == DCCP_PKT_CLOSEREQ)) ||
+ (dh->dccph_type == DCCP_PKT_RESPONSE ||
+ dh->dccph_type == DCCP_PKT_CLOSEREQ)) ||
(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, DCCP_SKB_CB(skb)->dccpd_seq);
+ (sk->sk_state == DCCP_RESPOND &&
+ dh->dccph_type == DCCP_PKT_DATA)) {
+ dccp_send_sync(sk, DCCP_SKB_CB(skb)->dccpd_seq,
+ DCCP_PKT_SYNC);
+ goto discard;
+ } else if (dh->dccph_type == DCCP_PKT_CLOSEREQ) {
+ dccp_rcv_closereq(sk, skb);
goto discard;
+ } else if (dh->dccph_type == DCCP_PKT_CLOSE) {
+ dccp_rcv_close(sk, skb);
+ return 0;
}
switch (sk->sk_state) {
case DCCP_CLOSED:
return 1;
- case DCCP_LISTEN:
- if (dh->dccph_type == DCCP_PKT_ACK ||
- dh->dccph_type == DCCP_PKT_DATAACK)
- return 1;
-
- if (dh->dccph_type == DCCP_PKT_RESET)
- goto discard;
-
- if (dh->dccph_type == DCCP_PKT_REQUEST) {
- if (dccp_v4_conn_request(sk, skb) < 0)
- return 1;
-
- /* FIXME: do congestion control initialization */
- goto discard;
- }
- goto discard;
-
case DCCP_REQUESTING:
/* FIXME: do congestion control initialization */
case DCCP_RESPOND:
case DCCP_PARTOPEN:
- queued = dccp_rcv_respond_partopen_state_process(sk, skb, dh, len);
+ queued = dccp_rcv_respond_partopen_state_process(sk, skb,
+ dh, len);
break;
}
- if (dh->dccph_type == DCCP_PKT_ACK || dh->dccph_type == DCCP_PKT_DATAACK) {
+ if (dh->dccph_type == DCCP_PKT_ACK ||
+ dh->dccph_type == DCCP_PKT_DATAACK) {
switch (old_state) {
case DCCP_PARTOPEN:
sk->sk_state_change(sk);