From 51c7d4fa2675c106a980ddcdbe308b54b5151945 Mon Sep 17 00:00:00 2001 From: Gerrit Renker Date: Thu, 4 Sep 2008 07:30:19 +0200 Subject: dccp: Implement both feature-local and feature-remote Sequence Window feature This adds full support for local/remote Sequence Window feature, from which the * sequence-number-validity (W) and * acknowledgment-number-validity (W') windows derive as specified in RFC 4340, 7.5.3. Specifically, the following changes are introduced: * integrated new socket fields into dccp_sk; * updated the update_gsr/gss routines with regard to these fields; * updated handler code: the Sequence Window feature is located at the TX side, so the local feature is meant if the handler-rx flag is false; * the initialisation of `rcv_wnd' in reqsk is removed, since - rcv_wnd is not used by the code anywhere; - sequence number checks are not done in the LISTEN state (cf. 7.5.3); - dccp_check_req checks the Ack number validity more rigorously; * the `struct dccp_minisock' became empty and is now removed. Until the handshake completes with activating negotiated values, the local/remote Sequence-Window values are undefined and thus can not reliably be estimated. This issue is addressed in a separate patch. Signed-off-by: Gerrit Renker Acked-by: Ian McDonald --- net/dccp/dccp.h | 16 +++++++--------- net/dccp/feat.c | 13 +++++++++++-- net/dccp/minisocks.c | 11 ----------- net/dccp/proto.c | 2 -- 4 files changed, 18 insertions(+), 24 deletions(-) (limited to 'net/dccp') diff --git a/net/dccp/dccp.h b/net/dccp/dccp.h index 3fd16e82c00..6101ecdb85b 100644 --- a/net/dccp/dccp.h +++ b/net/dccp/dccp.h @@ -409,23 +409,21 @@ static inline void dccp_hdr_set_ack(struct dccp_hdr_ack_bits *dhack, static inline void dccp_update_gsr(struct sock *sk, u64 seq) { struct dccp_sock *dp = dccp_sk(sk); - const struct dccp_minisock *dmsk = dccp_msk(sk); dp->dccps_gsr = seq; - dccp_set_seqno(&dp->dccps_swl, - dp->dccps_gsr + 1 - (dmsk->dccpms_sequence_window / 4)); - dccp_set_seqno(&dp->dccps_swh, - dp->dccps_gsr + (3 * dmsk->dccpms_sequence_window) / 4); + /* Sequence validity window depends on remote Sequence Window (7.5.1) */ + dp->dccps_swl = SUB48(ADD48(dp->dccps_gsr, 1), dp->dccps_r_seq_win / 4); + dp->dccps_swh = ADD48(dp->dccps_gsr, (3 * dp->dccps_r_seq_win) / 4); } static inline void dccp_update_gss(struct sock *sk, u64 seq) { struct dccp_sock *dp = dccp_sk(sk); - dp->dccps_awh = dp->dccps_gss = seq; - dccp_set_seqno(&dp->dccps_awl, - (dp->dccps_gss - - dccp_msk(sk)->dccpms_sequence_window + 1)); + dp->dccps_gss = seq; + /* Ack validity window depends on local Sequence Window value (7.5.1) */ + dp->dccps_awl = SUB48(ADD48(dp->dccps_gss, 1), dp->dccps_l_seq_win); + dp->dccps_awh = dp->dccps_gss; } static inline int dccp_ack_pending(const struct sock *sk) diff --git a/net/dccp/feat.c b/net/dccp/feat.c index 9a493809278..84346599985 100644 --- a/net/dccp/feat.c +++ b/net/dccp/feat.c @@ -52,8 +52,17 @@ static int dccp_hdlr_ccid(struct sock *sk, u64 ccid, bool rx) static int dccp_hdlr_seq_win(struct sock *sk, u64 seq_win, bool rx) { - if (!rx) - dccp_msk(sk)->dccpms_sequence_window = seq_win; + struct dccp_sock *dp = dccp_sk(sk); + + if (rx) { + dp->dccps_r_seq_win = seq_win; + /* propagate changes to update SWL/SWH */ + dccp_update_gsr(sk, dp->dccps_gsr); + } else { + dp->dccps_l_seq_win = seq_win; + /* propagate changes to update AWL */ + dccp_update_gss(sk, dp->dccps_gss); + } return 0; } diff --git a/net/dccp/minisocks.c b/net/dccp/minisocks.c index 0ebf8ebcf3d..0ecb19c5e8c 100644 --- a/net/dccp/minisocks.c +++ b/net/dccp/minisocks.c @@ -42,11 +42,6 @@ struct inet_timewait_death_row dccp_death_row = { EXPORT_SYMBOL_GPL(dccp_death_row); -void dccp_minisock_init(struct dccp_minisock *dmsk) -{ - dmsk->dccpms_sequence_window = sysctl_dccp_feat_sequence_window; -} - void dccp_time_wait(struct sock *sk, int state, int timeo) { struct inet_timewait_sock *tw = NULL; @@ -110,7 +105,6 @@ struct sock *dccp_create_openreq_child(struct sock *sk, struct dccp_request_sock *dreq = dccp_rsk(req); struct inet_connection_sock *newicsk = inet_csk(newsk); struct dccp_sock *newdp = dccp_sk(newsk); - struct dccp_minisock *newdmsk = dccp_msk(newsk); newdp->dccps_role = DCCP_ROLE_SERVER; newdp->dccps_hc_rx_ackvec = NULL; @@ -128,10 +122,6 @@ struct sock *dccp_create_openreq_child(struct sock *sk, * Initialize S.GAR := S.ISS * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookies */ - - /* See dccp_v4_conn_request */ - newdmsk->dccpms_sequence_window = req->rcv_wnd; - newdp->dccps_gar = newdp->dccps_iss = dreq->dreq_iss; dccp_update_gss(newsk, dreq->dreq_iss); @@ -289,7 +279,6 @@ int dccp_reqsk_init(struct request_sock *req, inet_rsk(req)->rmt_port = dccp_hdr(skb)->dccph_sport; inet_rsk(req)->acked = 0; - req->rcv_wnd = sysctl_dccp_feat_sequence_window; dreq->dreq_timestamp_echo = 0; /* inherit feature negotiation options from listening socket */ diff --git a/net/dccp/proto.c b/net/dccp/proto.c index 775eaa3d0c4..392a5d822b3 100644 --- a/net/dccp/proto.c +++ b/net/dccp/proto.c @@ -180,8 +180,6 @@ int dccp_init_sock(struct sock *sk, const __u8 ctl_sock_initialized) struct dccp_sock *dp = dccp_sk(sk); struct inet_connection_sock *icsk = inet_csk(sk); - dccp_minisock_init(&dp->dccps_minisock); - icsk->icsk_rto = DCCP_TIMEOUT_INIT; icsk->icsk_syn_retries = sysctl_dccp_request_retries; sk->sk_state = DCCP_CLOSED; -- cgit v1.2.3