aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorGerrit Renker <gerrit@erg.abdn.ac.uk>2008-09-04 07:30:19 +0200
committerGerrit Renker <gerrit@erg.abdn.ac.uk>2008-09-04 07:45:32 +0200
commit51c7d4fa2675c106a980ddcdbe308b54b5151945 (patch)
tree0c1f2b1a3323582fb8629ba7826e08710271ed49
parent09856c108956c99088ead9267ccbd1dab77f7043 (diff)
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 <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
-rw-r--r--Documentation/networking/dccp.txt3
-rw-r--r--include/linux/dccp.h24
-rw-r--r--net/dccp/dccp.h16
-rw-r--r--net/dccp/feat.c13
-rw-r--r--net/dccp/minisocks.c11
-rw-r--r--net/dccp/proto.c2
6 files changed, 24 insertions, 45 deletions
diff --git a/Documentation/networking/dccp.txt b/Documentation/networking/dccp.txt
index 7a3bb1abb83..b132e4a3cf0 100644
--- a/Documentation/networking/dccp.txt
+++ b/Documentation/networking/dccp.txt
@@ -141,7 +141,8 @@ rx_ccid = 2
Default CCID for the receiver-sender half-connection; see tx_ccid.
seq_window = 100
- The initial sequence window (sec. 7.5.2).
+ The initial sequence window (sec. 7.5.2) of the sender. This influences
+ the local ackno validity and the remote seqno validity windows (7.5.1).
tx_qlen = 5
The size of the transmit buffer in packets. A value of 0 corresponds
diff --git a/include/linux/dccp.h b/include/linux/dccp.h
index 990e97fa1f0..7a0502ab383 100644
--- a/include/linux/dccp.h
+++ b/include/linux/dccp.h
@@ -364,19 +364,6 @@ static inline unsigned int dccp_hdr_len(const struct sk_buff *skb)
#define DCCPF_INITIAL_SEND_NDP_COUNT 1
/**
- * struct dccp_minisock - Minimal DCCP connection representation
- *
- * Will be used to pass the state from dccp_request_sock to dccp_sock.
- *
- * @dccpms_sequence_window - Sequence Window Feature (section 7.5.2)
- */
-struct dccp_minisock {
- __u64 dccpms_sequence_window;
-};
-
-extern void dccp_minisock_init(struct dccp_minisock *dmsk);
-
-/**
* struct dccp_request_sock - represent DCCP-specific connection request
* @dreq_inet_rsk: structure inherited from
* @dreq_iss: initial sequence number sent on the Response (RFC 4340, 7.1)
@@ -464,13 +451,14 @@ struct dccp_ackvec;
* @dccps_timestamp_time - time of receiving latest @dccps_timestamp_echo
* @dccps_l_ack_ratio - feature-local Ack Ratio
* @dccps_r_ack_ratio - feature-remote Ack Ratio
+ * @dccps_l_seq_win - local Sequence Window (influences ack number validity)
+ * @dccps_r_seq_win - remote Sequence Window (influences seq number validity)
* @dccps_pcslen - sender partial checksum coverage (via sockopt)
* @dccps_pcrlen - receiver partial checksum coverage (via sockopt)
* @dccps_send_ndp_count - local Send NDP Count feature (7.7.2)
* @dccps_ndp_count - number of Non Data Packets since last data packet
* @dccps_mss_cache - current value of MSS (path MTU minus header sizes)
* @dccps_rate_last - timestamp for rate-limiting DCCP-Sync (RFC 4340, 7.5.4)
- * @dccps_minisock - associated minisock (accessed via dccp_msk)
* @dccps_featneg - tracks feature-negotiation state (mostly during handshake)
* @dccps_hc_rx_ackvec - rx half connection ack vector
* @dccps_hc_rx_ccid - CCID used for the receiver (or receiving half-connection)
@@ -504,12 +492,13 @@ struct dccp_sock {
__u32 dccps_timestamp_time;
__u16 dccps_l_ack_ratio;
__u16 dccps_r_ack_ratio;
+ __u64 dccps_l_seq_win:48;
+ __u64 dccps_r_seq_win:48;
__u8 dccps_pcslen:4;
__u8 dccps_pcrlen:4;
__u8 dccps_send_ndp_count:1;
__u64 dccps_ndp_count:48;
unsigned long dccps_rate_last;
- struct dccp_minisock dccps_minisock;
struct list_head dccps_featneg;
struct dccp_ackvec *dccps_hc_rx_ackvec;
struct ccid *dccps_hc_rx_ccid;
@@ -527,11 +516,6 @@ static inline struct dccp_sock *dccp_sk(const struct sock *sk)
return (struct dccp_sock *)sk;
}
-static inline struct dccp_minisock *dccp_msk(const struct sock *sk)
-{
- return (struct dccp_minisock *)&dccp_sk(sk)->dccps_minisock;
-}
-
static inline const char *dccp_role(const struct sock *sk)
{
switch (dccp_sk(sk)->dccps_role) {
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;