static void dccp_terminate_connection(struct sock *sk) { u8 next_state = DCCP_CLOSED; switch (sk->sk_state) { case DCCP_PASSIVE_CLOSE: case DCCP_PASSIVE_CLOSEREQ: dccp_finish_passive_close(sk); break; case DCCP_PARTOPEN: dccp_pr_debug("Stop PARTOPEN timer (%p)\n", sk); inet_csk_clear_xmit_timer(sk, ICSK_TIME_DACK); /* fall through */ case DCCP_OPEN: dccp_send_close(sk, 1); if (dccp_sk(sk)->dccps_role == DCCP_ROLE_SERVER && !dccp_sk(sk)->dccps_server_timewait) next_state = DCCP_ACTIVE_CLOSEREQ; else next_state = DCCP_CLOSING; /* fall through */ default: dccp_set_state(sk, next_state); } }
static int dccp_rcv_respond_partopen_state_process(struct sock *sk, struct sk_buff *skb, const struct dccp_hdr *dh, const unsigned len) { int queued = 0; switch (dh->dccph_type) { case DCCP_PKT_RESET: inet_csk_clear_xmit_timer(sk, ICSK_TIME_DACK); break; case DCCP_PKT_DATA: if (sk->sk_state == DCCP_RESPOND) break; 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. */ /* Stop the PARTOPEN timer */ if (sk->sk_state == DCCP_PARTOPEN) inet_csk_clear_xmit_timer(sk, ICSK_TIME_DACK); dccp_sk(sk)->dccps_osr = DCCP_SKB_CB(skb)->dccpd_seq; dccp_set_state(sk, DCCP_OPEN); if (dh->dccph_type == DCCP_PKT_DATAACK || dh->dccph_type == DCCP_PKT_DATA) { __dccp_rcv_established(sk, skb, dh, len); queued = 1; /* packet was queued (by __dccp_rcv_established) */ } break; } return queued; }
static inline void dccp_event_ack_sent(struct sock *sk) { inet_csk_clear_xmit_timer(sk, ICSK_TIME_DACK); }
static int dccp_rcv_request_sent_state_process(struct sock *sk, struct sk_buff *skb, const struct dccp_hdr *dh, const unsigned len) { /* * Step 4: Prepare sequence numbers in REQUEST * If S.state == REQUEST, * If (P.type == Response or P.type == Reset) * and S.AWL <= P.ackno <= S.AWH, * / * Set sequence number variables corresponding to the * other endpoint, so P will pass the tests in Step 6 * / * Set S.GSR, S.ISR, S.SWL, S.SWH * / * Response processing continues in Step 10; Reset * processing continues in Step 9 * / */ if (dh->dccph_type == DCCP_PKT_RESPONSE) { const struct inet_connection_sock *icsk = inet_csk(sk); struct dccp_sock *dp = dccp_sk(sk); /* Stop the REQUEST timer */ inet_csk_clear_xmit_timer(sk, ICSK_TIME_RETRANS); BUG_TRAP(sk->sk_send_head != NULL); __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", (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; } if (dccp_parse_options(sk, skb)) goto out_invalid_packet; 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 */ 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 */ dccp_set_seqno(&dp->dccps_swl, max48(dp->dccps_swl, dp->dccps_isr)); dccp_sync_mss(sk, icsk->icsk_pmtu_cookie); /* * 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 * / * S.state := PARTOPEN * Set PARTOPEN timer * Continue with S.state == PARTOPEN * / * Step 12 will send the Ack completing the * three-way handshake * / */ dccp_set_state(sk, DCCP_PARTOPEN); /* Make sure socket is routed, for correct metrics. */ icsk->icsk_af_ops->rebuild_header(sk); if (!sock_flag(sk, SOCK_DEAD)) { sk->sk_state_change(sk); sk_wake_async(sk, 0, POLL_OUT); } if (sk->sk_write_pending || icsk->icsk_ack.pingpong || icsk->icsk_accept_queue.rskq_defer_accept) { /* Save one ACK. Data will be ready after * several ticks, if write_pending is set. * * It may be deleted, but with this feature tcpdumps * look so _wonderfully_ clever, that I was not able * to stand against the temptation 8) --ANK */ /* * OK, in DCCP we can as well do a similar trick, its * even in the draft, but there is no need for us to * schedule an ack here, as dccp_sendmsg does this for * us, also stated in the draft. -acme */ __kfree_skb(skb); return 0; } dccp_send_ack(sk); return -1; } 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; }