diff options
Diffstat (limited to 'net/dccp/output.c')
| -rw-r--r-- | net/dccp/output.c | 55 |
1 files changed, 42 insertions, 13 deletions
diff --git a/net/dccp/output.c b/net/dccp/output.c index f49544618f2..3b763db3d86 100644 --- a/net/dccp/output.c +++ b/net/dccp/output.c @@ -133,15 +133,31 @@ static int dccp_transmit_skb(struct sock *sk, struct sk_buff *skb) return -ENOBUFS; } +/** + * dccp_determine_ccmps - Find out about CCID-specfic packet-size limits + * We only consider the HC-sender CCID for setting the CCMPS (RFC 4340, 14.), + * since the RX CCID is restricted to feedback packets (Acks), which are small + * in comparison with the data traffic. A value of 0 means "no current CCMPS". + */ +static u32 dccp_determine_ccmps(const struct dccp_sock *dp) +{ + const struct ccid *tx_ccid = dp->dccps_hc_tx_ccid; + + if (tx_ccid == NULL || tx_ccid->ccid_ops == NULL) + return 0; + return tx_ccid->ccid_ops->ccid_ccmps; +} + unsigned int dccp_sync_mss(struct sock *sk, u32 pmtu) { struct inet_connection_sock *icsk = inet_csk(sk); struct dccp_sock *dp = dccp_sk(sk); - int mss_now = (pmtu - icsk->icsk_af_ops->net_header_len - - sizeof(struct dccp_hdr) - sizeof(struct dccp_hdr_ext)); + u32 ccmps = dccp_determine_ccmps(dp); + int cur_mps = ccmps ? min(pmtu, ccmps) : pmtu; - /* Now subtract optional transport overhead */ - mss_now -= icsk->icsk_ext_hdr_len; + /* Account for header lengths and IPv4/v6 option overhead */ + cur_mps -= (icsk->icsk_af_ops->net_header_len + icsk->icsk_ext_hdr_len + + sizeof(struct dccp_hdr) + sizeof(struct dccp_hdr_ext)); /* * FIXME: this should come from the CCID infrastructure, where, say, @@ -151,13 +167,13 @@ unsigned int dccp_sync_mss(struct sock *sk, u32 pmtu) * make it a multiple of 4 */ - mss_now -= ((5 + 6 + 10 + 6 + 6 + 6 + 3) / 4) * 4; + cur_mps -= ((5 + 6 + 10 + 6 + 6 + 6 + 3) / 4) * 4; /* And store cached results */ icsk->icsk_pmtu_cookie = pmtu; - dp->dccps_mss_cache = mss_now; + dp->dccps_mss_cache = cur_mps; - return mss_now; + return cur_mps; } EXPORT_SYMBOL_GPL(dccp_sync_mss); @@ -170,7 +186,7 @@ void dccp_write_space(struct sock *sk) wake_up_interruptible(sk->sk_sleep); /* Should agree with poll, otherwise some programs break */ if (sock_writeable(sk)) - sk_wake_async(sk, 2, POLL_OUT); + sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT); read_unlock(&sk->sk_callback_lock); } @@ -303,7 +319,7 @@ struct sk_buff *dccp_make_response(struct sock *sk, struct dst_entry *dst, DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_RESPONSE; DCCP_SKB_CB(skb)->dccpd_seq = dreq->dreq_iss; - if (dccp_insert_options(sk, skb)) { + if (dccp_insert_options_rsk(dreq, skb)) { kfree_skb(skb); return NULL; } @@ -391,7 +407,7 @@ int dccp_send_reset(struct sock *sk, enum dccp_reset_codes code) * FIXME: what if rebuild_header fails? * Should we be doing a rebuild_header here? */ - int err = inet_sk_rebuild_header(sk); + int err = inet_csk(sk)->icsk_af_ops->rebuild_header(sk); if (err != 0) return err; @@ -567,14 +583,27 @@ void dccp_send_close(struct sock *sk, const int active) /* Reserve space for headers and prepare control bits. */ skb_reserve(skb, sk->sk_prot->max_header); - DCCP_SKB_CB(skb)->dccpd_type = dp->dccps_role == DCCP_ROLE_CLIENT ? - DCCP_PKT_CLOSE : DCCP_PKT_CLOSEREQ; + if (dp->dccps_role == DCCP_ROLE_SERVER && !dp->dccps_server_timewait) + DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_CLOSEREQ; + else + DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_CLOSE; if (active) { dccp_write_xmit(sk, 1); dccp_skb_entail(sk, skb); dccp_transmit_skb(sk, skb_clone(skb, prio)); - /* FIXME do we need a retransmit timer here? */ + /* + * Retransmission timer for active-close: RFC 4340, 8.3 requires + * to retransmit the Close/CloseReq until the CLOSING/CLOSEREQ + * state can be left. The initial timeout is 2 RTTs. + * Since RTT measurement is done by the CCIDs, there is no easy + * way to get an RTT sample. The fallback RTT from RFC 4340, 3.4 + * is too low (200ms); we use a high value to avoid unnecessary + * retransmissions when the link RTT is > 0.2 seconds. + * FIXME: Let main module sample RTTs and use that instead. + */ + inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, + DCCP_TIMEOUT_INIT, DCCP_RTO_MAX); } else dccp_transmit_skb(sk, skb); } |