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  1. 13 12月, 2008 5 次提交
  3. 12 12月, 2008 4 次提交
  5. 11 12月, 2008 12 次提交
  7. 10 12月, 2008 13 次提交
  9. 09 12月, 2008 4 次提交
  11. 08 12月, 2008 2 次提交
    • G
      dccp ccid-2: Phase out the use of boolean Ack Vector sysctl · 6fdd34d4
      由 Gerrit Renker 提交于 
      This removes the use of the sysctl and the minisock variable for the Send Ack
Vector feature, as it now is handled fully dynamically via feature negotiation
(i.e. when CCID-2 is enabled, Ack Vectors are automatically enabled as per
 RFC 4341, 4.).

Using a sysctl in parallel to this implementation would open the door to
crashes, since much of the code relies on tests of the boolean minisock /
sysctl variable. Thus, this patch replaces all tests of type

	if (dccp_msk(sk)->dccpms_send_ack_vector)
		/* ... */
with
	if (dp->dccps_hc_rx_ackvec != NULL)
		/* ... */

The dccps_hc_rx_ackvec is allocated by the dccp_hdlr_ackvec() when feature
negotiation concluded that Ack Vectors are to be used on the half-connection.
Otherwise, it is NULL (due to dccp_init_sock/dccp_create_openreq_child),
so that the test is a valid one.

The activation handler for Ack Vectors is called as soon as the feature
negotiation has concluded at the
 * server when the Ack marking the transition RESPOND => OPEN arrives;
 * client after it has sent its ACK, marking the transition REQUEST => PARTOPEN.

Adding the sequence number of the Response packet to the Ack Vector has been
removed, since
 (a) connection establishment implies that the Response has been received;
 (b) the CCIDs only look at packets received in the (PART)OPEN state, i.e.
     this entry will always be ignored;
 (c) it can not be used for anything useful - to detect loss for instance, only
     packets received after the loss can serve as pseudo-dupacks.

There was a FIXME to change the error code when dccp_ackvec_add() fails.
I removed this after finding out that:
 * the check whether ackno < ISN is already made earlier,
 * this Response is likely the 1st packet with an Ackno that the client gets,
 * so when dccp_ackvec_add() fails, the reason is likely not a packet error.
Signed-off-by: NGerrit Renker <gerrit@erg.abdn.ac.uk>
Acked-by: NIan McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      6fdd34d4
    • G
      dccp: Remove manual influence on NDP Count feature · 4098dce5
      由 Gerrit Renker 提交于 
      Updating the NDP count feature is handled automatically now:
 * for CCID-2 it is disabled, since the code does not use NDP counts;
 * for CCID-3 it is enabled, as NDP counts are used to determine loss lengths.

Allowing the user to change NDP values leads to unpredictable and failing
behaviour, since it is then possible to disable NDP counts even when they
are needed (e.g. in CCID-3).

This means that only those user settings are sensible that agree with the
values for Send NDP Count implied by the choice of CCID. But those settings
are already activated by the feature negotiation (CCID dependency tracking),
hence this form of support is redundant.

At startup the initialisation of the NDP count feature uses the default
value of 0, which is done implicitly by the zeroing-out of the socket when
it is allocated. If the choice of CCID or feature negotiation enables NDP
count, this will then be updated via the NDP activation handler.
Signed-off-by: NGerrit Renker <gerrit@erg.abdn.ac.uk>
Acked-by: NIan McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      4098dce5