X-Git-Url: http://pilppa.org/gitweb/?a=blobdiff_plain;f=net%2Fdccp%2Finput.c;h=08392ed86c25403ea574c1e2b39786b8488e4625;hb=fe2c802ab62aa63d276deafa905875f3455f2621;hp=1ce101062824ef25fca9280889a572ae2c62408b;hpb=14f7d720bb6cc60be8931ea1a0f547dc1e475b88;p=linux-2.6-omap-h63xx.git diff --git a/net/dccp/input.c b/net/dccp/input.c index 1ce10106282..08392ed86c2 100644 --- a/net/dccp/input.c +++ b/net/dccp/input.c @@ -22,26 +22,77 @@ /* rate-limit for syncs in reply to sequence-invalid packets; RFC 4340, 7.5.4 */ int sysctl_dccp_sync_ratelimit __read_mostly = HZ / 8; -static void dccp_fin(struct sock *sk, struct sk_buff *skb) +static void dccp_enqueue_skb(struct sock *sk, struct sk_buff *skb) { - sk->sk_shutdown |= RCV_SHUTDOWN; - sock_set_flag(sk, SOCK_DONE); __skb_pull(skb, dccp_hdr(skb)->dccph_doff * 4); __skb_queue_tail(&sk->sk_receive_queue, skb); skb_set_owner_r(skb, sk); sk->sk_data_ready(sk, 0); } -static void dccp_rcv_close(struct sock *sk, struct sk_buff *skb) +static void dccp_fin(struct sock *sk, struct sk_buff *skb) { - dccp_send_reset(sk, DCCP_RESET_CODE_CLOSED); - dccp_fin(sk, skb); - dccp_set_state(sk, DCCP_CLOSED); - sk_wake_async(sk, 1, POLL_HUP); + /* + * On receiving Close/CloseReq, both RD/WR shutdown are performed. + * RFC 4340, 8.3 says that we MAY send further Data/DataAcks after + * receiving the closing segment, but there is no guarantee that such + * data will be processed at all. + */ + sk->sk_shutdown = SHUTDOWN_MASK; + sock_set_flag(sk, SOCK_DONE); + dccp_enqueue_skb(sk, skb); +} + +static int dccp_rcv_close(struct sock *sk, struct sk_buff *skb) +{ + int queued = 0; + + switch (sk->sk_state) { + /* + * We ignore Close when received in one of the following states: + * - CLOSED (may be a late or duplicate packet) + * - PASSIVE_CLOSEREQ (the peer has sent a CloseReq earlier) + * - RESPOND (already handled by dccp_check_req) + */ + case DCCP_CLOSING: + /* + * Simultaneous-close: receiving a Close after sending one. This + * can happen if both client and server perform active-close and + * will result in an endless ping-pong of crossing and retrans- + * mitted Close packets, which only terminates when one of the + * nodes times out (min. 64 seconds). Quicker convergence can be + * achieved when one of the nodes acts as tie-breaker. + * This is ok as both ends are done with data transfer and each + * end is just waiting for the other to acknowledge termination. + */ + if (dccp_sk(sk)->dccps_role != DCCP_ROLE_CLIENT) + break; + /* fall through */ + case DCCP_REQUESTING: + case DCCP_ACTIVE_CLOSEREQ: + dccp_send_reset(sk, DCCP_RESET_CODE_CLOSED); + dccp_done(sk); + break; + case DCCP_OPEN: + case DCCP_PARTOPEN: + /* Give waiting application a chance to read pending data */ + queued = 1; + dccp_fin(sk, skb); + dccp_set_state(sk, DCCP_PASSIVE_CLOSE); + /* fall through */ + case DCCP_PASSIVE_CLOSE: + /* + * Retransmitted Close: we have already enqueued the first one. + */ + sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_HUP); + } + return queued; } -static void dccp_rcv_closereq(struct sock *sk, struct sk_buff *skb) +static int dccp_rcv_closereq(struct sock *sk, struct sk_buff *skb) { + int queued = 0; + /* * Step 7: Check for unexpected packet types * If (S.is_server and P.type == CloseReq) @@ -50,12 +101,26 @@ static void dccp_rcv_closereq(struct sock *sk, struct sk_buff *skb) */ if (dccp_sk(sk)->dccps_role != DCCP_ROLE_CLIENT) { dccp_send_sync(sk, DCCP_SKB_CB(skb)->dccpd_seq, DCCP_PKT_SYNC); - return; + return queued; } - if (sk->sk_state != DCCP_CLOSING) + /* Step 13: process relevant Client states < CLOSEREQ */ + switch (sk->sk_state) { + case DCCP_REQUESTING: + dccp_send_close(sk, 0); dccp_set_state(sk, DCCP_CLOSING); - dccp_send_close(sk, 0); + break; + case DCCP_OPEN: + case DCCP_PARTOPEN: + /* Give waiting application a chance to read pending data */ + queued = 1; + dccp_fin(sk, skb); + dccp_set_state(sk, DCCP_PASSIVE_CLOSEREQ); + /* fall through */ + case DCCP_PASSIVE_CLOSEREQ: + sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_HUP); + } + return queued; } static u8 dccp_reset_code_convert(const u8 code) @@ -90,7 +155,7 @@ static void dccp_rcv_reset(struct sock *sk, struct sk_buff *skb) dccp_fin(sk, skb); if (err && !sock_flag(sk, SOCK_DEAD)) - sk_wake_async(sk, 0, POLL_ERR); + sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR); dccp_time_wait(sk, DCCP_TIME_WAIT, 0); } @@ -103,6 +168,21 @@ static void dccp_event_ack_recv(struct sock *sk, struct sk_buff *skb) DCCP_SKB_CB(skb)->dccpd_ack_seq); } +static void dccp_deliver_input_to_ccids(struct sock *sk, struct sk_buff *skb) +{ + const struct dccp_sock *dp = dccp_sk(sk); + + /* Don't deliver to RX CCID when node has shut down read end. */ + if (!(sk->sk_shutdown & RCV_SHUTDOWN)) + ccid_hc_rx_packet_recv(dp->dccps_hc_rx_ccid, sk, skb); + /* + * Until the TX queue has been drained, we can not honour SHUT_WR, since + * we need received feedback as input to adjust congestion control. + */ + if (sk->sk_write_queue.qlen > 0 || !(sk->sk_shutdown & SEND_SHUTDOWN)) + ccid_hc_tx_packet_recv(dp->dccps_hc_tx_ccid, sk, skb); +} + static int dccp_check_seqno(struct sock *sk, struct sk_buff *skb) { const struct dccp_hdr *dh = dccp_hdr(skb); @@ -209,13 +289,11 @@ static int __dccp_rcv_established(struct sock *sk, struct sk_buff *skb, case DCCP_PKT_DATAACK: case DCCP_PKT_DATA: /* - * FIXME: check if sk_receive_queue is full, schedule DATA_DROPPED - * option if it is. + * FIXME: schedule DATA_DROPPED (RFC 4340, 11.7.2) if and when + * - sk_shutdown == RCV_SHUTDOWN, use Code 1, "Not Listening" + * - sk_receive_queue is full, use Code 2, "Receive Buffer" */ - __skb_pull(skb, dh->dccph_doff * 4); - __skb_queue_tail(&sk->sk_receive_queue, skb); - skb_set_owner_r(skb, sk); - sk->sk_data_ready(sk, 0); + dccp_enqueue_skb(sk, skb); return 0; case DCCP_PKT_ACK: goto discard; @@ -231,11 +309,13 @@ static int __dccp_rcv_established(struct sock *sk, struct sk_buff *skb, dccp_rcv_reset(sk, skb); return 0; case DCCP_PKT_CLOSEREQ: - dccp_rcv_closereq(sk, skb); + if (dccp_rcv_closereq(sk, skb)) + return 0; goto discard; case DCCP_PKT_CLOSE: - dccp_rcv_close(sk, skb); - return 0; + if (dccp_rcv_close(sk, skb)) + return 0; + goto discard; case DCCP_PKT_REQUEST: /* Step 7 * or (S.is_server and P.type == Response) @@ -289,7 +369,7 @@ int dccp_rcv_established(struct sock *sk, struct sk_buff *skb, if (dccp_check_seqno(sk, skb)) goto discard; - if (dccp_parse_options(sk, skb)) + if (dccp_parse_options(sk, NULL, skb)) goto discard; if (DCCP_SKB_CB(skb)->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ) @@ -300,9 +380,7 @@ int dccp_rcv_established(struct sock *sk, struct sk_buff *skb, DCCP_SKB_CB(skb)->dccpd_seq, DCCP_ACKVEC_STATE_RECEIVED)) goto discard; - - ccid_hc_rx_packet_recv(dp->dccps_hc_rx_ccid, sk, skb); - ccid_hc_tx_packet_recv(dp->dccps_hc_tx_ccid, sk, skb); + dccp_deliver_input_to_ccids(sk, skb); return __dccp_rcv_established(sk, skb, dh, len); discard: @@ -349,7 +427,7 @@ static int dccp_rcv_request_sent_state_process(struct sock *sk, goto out_invalid_packet; } - if (dccp_parse_options(sk, skb)) + if (dccp_parse_options(sk, NULL, skb)) goto out_invalid_packet; /* Obtain usec RTT sample from SYN exchange (used by CCID 3) */ @@ -402,7 +480,7 @@ static int dccp_rcv_request_sent_state_process(struct sock *sk, if (!sock_flag(sk, SOCK_DEAD)) { sk->sk_state_change(sk); - sk_wake_async(sk, 0, POLL_OUT); + sk_wake_async(sk, SOCK_WAKE_IO, POLL_OUT); } if (sk->sk_write_pending || icsk->icsk_ack.pingpong || @@ -531,7 +609,7 @@ int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb, /* * Step 8: Process options and mark acknowledgeable */ - if (dccp_parse_options(sk, skb)) + if (dccp_parse_options(sk, NULL, skb)) goto discard; if (dcb->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ) @@ -543,8 +621,7 @@ int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb, DCCP_ACKVEC_STATE_RECEIVED)) goto discard; - ccid_hc_rx_packet_recv(dp->dccps_hc_rx_ccid, sk, skb); - ccid_hc_tx_packet_recv(dp->dccps_hc_tx_ccid, sk, skb); + dccp_deliver_input_to_ccids(sk, skb); } /* @@ -560,16 +637,14 @@ int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb, return 0; /* * Step 7: Check for unexpected packet types - * If (S.is_server and P.type == CloseReq) - * or (S.is_server and P.type == Response) + * 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 || - dh->dccph_type == DCCP_PKT_CLOSEREQ)) || + dh->dccph_type == DCCP_PKT_RESPONSE) || (dp->dccps_role == DCCP_ROLE_CLIENT && dh->dccph_type == DCCP_PKT_REQUEST) || (sk->sk_state == DCCP_RESPOND && @@ -577,11 +652,13 @@ int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb, dccp_send_sync(sk, dcb->dccpd_seq, DCCP_PKT_SYNC); goto discard; } else if (dh->dccph_type == DCCP_PKT_CLOSEREQ) { - dccp_rcv_closereq(sk, skb); + if (dccp_rcv_closereq(sk, skb)) + return 0; goto discard; } else if (dh->dccph_type == DCCP_PKT_CLOSE) { - dccp_rcv_close(sk, skb); - return 0; + if (dccp_rcv_close(sk, skb)) + return 0; + goto discard; } switch (sk->sk_state) { @@ -611,7 +688,7 @@ int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb, switch (old_state) { case DCCP_PARTOPEN: sk->sk_state_change(sk); - sk_wake_async(sk, 0, POLL_OUT); + sk_wake_async(sk, SOCK_WAKE_IO, POLL_OUT); break; } } else if (unlikely(dh->dccph_type == DCCP_PKT_SYNC)) {