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2008-01-28[DCCP]: Allow to parse options on Request SocketsGerrit Renker
The option parsing code currently only parses on full sk's. This causes a problem for options sent during the initial handshake (in particular timestamps and feature-negotiation options). Therefore, this patch extends the option parsing code with an additional argument for request_socks: if it is non-NULL, options are parsed on the request socket, otherwise the normal path (parsing on the sk) is used. Subsequent patches, which implement feature negotiation during connection setup, make use of this facility. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[DCCP]: Perform SHUT_RD and SHUT_WR on receiving closeGerrit Renker
This patch performs two changes: 1) Close the write-end in addition to the read-end when a fin-like segment (Close or CloseReq) is received by DCCP. This accounts for the fact that DCCP, in contrast to TCP, does not have a half-close. RFC 4340 says in this respect that when a fin-like segment has been sent there is no guarantee at all that any further data will be processed. Thus this patch performs SHUT_WR in addition to the SHUT_RD when a fin-like segment is encountered. 2) Minor change: I noted that code appears twice in different places and think it makes sense to put this into a self-contained function (dccp_enqueue()). Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[DCCP]: Remove duplicate test for CloseReqGerrit Renker
This removes a redundant test for unexpected packet types. In dccp_rcv_state_process it is tested twice whether a DCCP-server has received a CloseReq (Step 7): * first in the combined if-statement, * then in the call to dccp_rcv_closereq(). The latter is necesssary since dccp_rcv_closereq() is also called from __dccp_rcv_established(). This patch removes the duplicate test. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[DCCP]: Integrate state transitions for passive-closeGerrit Renker
This adds the necessary state transitions for the two forms of passive-close * PASSIVE_CLOSE - which is entered when a host receives a Close; * PASSIVE_CLOSEREQ - which is entered when a client receives a CloseReq. Here is a detailed account of what the patch does in each state. 1) Receiving CloseReq The pseudo-code in 8.5 says: Step 13: Process CloseReq If P.type == CloseReq and S.state < CLOSEREQ, Generate Close S.state := CLOSING Set CLOSING timer. This means we need to address what to do in CLOSED, LISTEN, REQUEST, RESPOND, PARTOPEN, and OPEN. * CLOSED: silently ignore - it may be a late or duplicate CloseReq; * LISTEN/RESPOND: will not appear, since Step 7 is performed first (we know we are the client); * REQUEST: perform Step 13 directly (no need to enqueue packet); * OPEN/PARTOPEN: enter PASSIVE_CLOSEREQ so that the application has a chance to process unread data. When already in PASSIVE_CLOSEREQ, no second CloseReq is enqueued. In any other state, the CloseReq is ignored. I think that this offers some robustness against rare and pathological cases: e.g. a simultaneous close where the client sends a Close and the server a CloseReq. The client will then be retransmitting its Close until it gets the Reset, so ignoring the CloseReq while in state CLOSING is sane. 2) Receiving Close The code below from 8.5 is unconditional. Step 14: Process Close If P.type == Close, Generate Reset(Closed) Tear down connection Drop packet and return Thus we need to consider all states: * CLOSED: silently ignore, since this can happen when a retransmitted or late Close arrives; * LISTEN: dccp_rcv_state_process() will generate a Reset ("No Connection"); * REQUEST: perform Step 14 directly (no need to enqueue packet); * RESPOND: dccp_check_req() will generate a Reset ("Packet Error") -- left it at that; * OPEN/PARTOPEN: enter PASSIVE_CLOSE so that application has a chance to process unread data; * CLOSEREQ: server performed active-close -- perform Step 14; * CLOSING: simultaneous-close: use a tie-breaker to avoid message ping-pong (see comment); * PASSIVE_CLOSEREQ: ignore - the peer has a bug (sending first a CloseReq and now a Close); * TIMEWAIT: packet is ignored. Note that the condition of receiving a packet in state CLOSED here is different from the condition "there is no socket for such a connection": the socket still exists, but its state indicates it is unusable. Last, dccp_finish_passive_close sets either DCCP_CLOSED or DCCP_CLOSING = TCP_CLOSING, so that sk_stream_wait_close() will wait for the final Reset (which will trigger CLOSING => CLOSED). Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[NET]: Name magic constants in sock_wake_async()Pavel Emelyanov
The sock_wake_async() performs a bit different actions depending on "how" argument. Unfortunately this argument ony has numerical magic values. I propose to give names to their constants to help people reading this function callers understand what's going on without looking into this function all the time. I suppose this is 2.6.25 material, but if it's not (or the naming seems poor/bad/awful), I can rework it against the current net-2.6 tree. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[DCCP]: Honour and make use of shutdown option set by userGerrit Renker
This extends the DCCP socket API by honouring any shutdown(2) option set by the user. The behaviour is, as much as possible, made consistent with the API for TCP's shutdown. This patch exploits the information provided by the user via the socket API to reduce processing costs: * if the read end is closed (SHUT_RD), it is not necessary to deliver to input CCID; * if the write end is closed (SHUT_WR), the same idea applies, but with a difference - as long as the TX queue has not been drained, we need to receive feedback to keep congestion-control rates up to date. Hence SHUT_WR is honoured only after the last packet (under congestion control) has been sent; * although SHUT_RDWR seems nonsensical, it is nevertheless supported in the same manner as for TCP (and agrees with test for SHUTDOWN_MASK in dccp_poll() in net/dccp/proto.c). Furthermore, most of the code already honours the sk_shutdown flags (dccp_recvmsg() for instance sets the read length to 0 if SHUT_RD had been called); CCID handling is now added to this by the present patch. There will also no longer be any delivery when the socket is in the final stages, i.e. when one of dccp_close(), dccp_fin(), or dccp_done() has been called - which is fine since at that stage the connection is its final stages. Motivation and background are on http://www.erg.abdn.ac.uk/users/gerrit/dccp/notes/shutdown A FIXME has been added to notify the other end if SHUT_RD has been set (RFC 4340, 11.7). Note: There is a comment in inet_shutdown() in net/ipv4/af_inet.c which asks to "make sure the socket is a TCP socket". This should probably be extended to mean `TCP or DCCP socket' (the code is also used by UDP and raw sockets). Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-24[DCCP]: Convert Reset code into socket error numberGerrit Renker
This adds support for converting the 11 currently defined Reset codes into system error numbers, which are stored in sk_err for further interpretation. This makes the externally visible API behaviour similar to TCP, since a client connecting to a non-existing port will experience ECONNREFUSED. * Code 0, Unspecified, is interpreted as non-error (0); * Code 1, Closed (normal termination), also maps into 0; * Code 2, Aborted, maps into "Connection reset by peer" (ECONNRESET); * Code 3, No Connection and Code 7, Connection Refused, map into "Connection refused" (ECONNREFUSED); * Code 4, Packet Error, maps into "No message of desired type" (ENOMSG); * Code 5, Option Error, maps into "Illegal byte sequence" (EILSEQ); * Code 6, Mandatory Error, maps into "Operation not supported on transport endpoint" (EOPNOTSUPP); * Code 8, Bad Service Code, maps into "Invalid request code" (EBADRQC); * Code 9, Too Busy, maps into "Too many users" (EUSERS); * Code 10, Bad Init Cookie, maps into "Invalid request descriptor" (EBADR); * Code 11, Aggression Penalty, maps into "Quota exceeded" (EDQUOT) which makes sense in terms of using more than the `fair share' of bandwidth. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2007-10-17[DCCP]: fix link error with !CONFIG_SYSCTLIngo Molnar
Do not define the sysctl_dccp_sync_ratelimit sysctl variable in the CONFIG_SYSCTL dependent sysctl.c module - move it to input.c instead. This fixes the following build bug: net/built-in.o: In function `dccp_check_seqno': input.c:(.text+0xbd859): undefined reference to `sysctl_dccp_sync_ratelimit' distcc[29953] ERROR: compile (null) on localhost failed make: *** [vmlinux] Error 1 Found via 'make randconfig' build testing. Signed-off-by: Ingo Molnar <mingo@elte.hu> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[DCCP]: Rate-limit DCCP-SyncsGerrit Renker
This implements a SHOULD from RFC 4340, 7.5.4: "To protect against denial-of-service attacks, DCCP implementations SHOULD impose a rate limit on DCCP-Syncs sent in response to sequence-invalid packets, such as not more than eight DCCP-Syncs per second." The rate-limit is maintained on a per-socket basis. This is a more stringent policy than enforcing the rate-limit on a per-source-address basis and protects against attacks with forged source addresses. Moreover, the mechanism is deliberately kept simple. In contrast to xrlim_allow(), bursts of Sync packets in reply to sequence-invalid packets are not supported. This foils such attacks where the receipt of a Sync triggers further sequence-invalid packets. (I have tested this mechanism against xrlim_allow algorithm for Syncs, permitting bursts just increases the problems.) In order to keep flexibility, the timeout parameter can be set via sysctl; and the whole mechanism can even be disabled (which is however not recommended). The algorithm in this patch has been improved with regard to wrapping issues thanks to a suggestion by Arnaldo. Commiter note: Rate limited the step 6 DCCP_WARN too, as it says we're sending a sync. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
2007-10-10[DCCP]: Send Reset upon Sync in state REQUESTGerrit Renker
This fixes the code to correspond to RFC 4340, 7.5.4, which states the exception that a Sync received in state REQUEST generates a Reset (not a SyncAck). To achieve this, only a small change is required. Since dccp_rcv_request_sent_state_process() already uses the correct Reset Code number 4 ("Packet Error"), we only need to shift the if-statement a few lines further down. (To test this case: replace DCCP_PKT_RESPONSE with DCCP_PKT_SYNC in dccp_make_response.) Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
2007-10-10[DCCP]: Fix Reset/Sync-Flood BugGerrit Renker
This updates sequence number checking with regard to RFC 4340, 7.5.4. Missing in the code was an exception for sequence-invalid Reset packets, which get a Sync acknowledging GSR, instead of (as usual) P.seqno. This can lead to an oscillating ping-pong flood of Reset packets. In fact, it has been observed on the wire as follows: 1. client establishes connection to server; 2. before server can write to client, client crashes without notifying the server (NB: now no longer possible due to ABORT function); 3. server sends DCCP-Data packet (has no ackno); 4. client generates Reset "No Connection", seqno=0, increments seqno; 5. server replies with Sync, using ackno = P.seqno; 6. client generates Reset "No Connection" with seqno = ackno + 1; 7. goto (5). The difference is that now in (5) the server uses GSR. This causes the Reset sent by the client in (6) to become sequence-valid, so that in (7) the vicious circle is broken; the Reset is then enqueued and causes the socket to enter TIMEWAIT state. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[DCCP]: Shorten variable names in dccp_check_seqnoGerrit Renker
This patch is in part required by the next patch; it * replaces 6 instances of `DCCP_SKB_CB(skb)->dccpd_seq' with `seqno'; * replaces 7 instances of `DCCP_SKB_CB(skb)->dccpd_ack_seq' with `ackno'; * replaces 1 use of dccp_inc_seqno() by unfolding `ADD48' macro in place. No changes in algorithm, all changes are text replacement/substitution. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[DCCP]: Simplify interface of dccp_sample_rttGerrit Renker
The third parameter of dccp_sample_rtt now becomes useless and is removed. Also combined the subtraction of the timestamp echo and the elapsed time. This is safe, since (a) presence of timestamp echo is tested first and (b) elapsed time is either present and non-zero or it is not set and equals 0 due to the memset in dccp_parse_options. To avoid measuring option-processing time, the timestamp for measuring the initial Request/Response RTT sample is taken directly when the function is called (the Linux implementation always adds a timestamp on the Request, so there is no loss in doing this). Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[DCCP]: Convert dccp_sample_rtt to ktime_tArnaldo Carvalho de Melo
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[DCCP]: Sample RTT from SYN exchangeGerrit Renker
Function:
2007-04-25[DCCP]: Provide function for RTT samplingGerrit Renker
A recurring problem, in particular in the CCID code, is that RTT samples from packets with timestamp echo and elapsed time options need to be taken. This service is provided via a new function dccp_sample_rtt in this patch. Furthermore, to protect against `insane' RTT samples, the sampled value is bounded between 100 microseconds and 4 seconds - for which u32 is sufficient. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[DCCP]: Remove ambiguity in the way before48 is usedGerrit Renker
This removes two ambiguities in employing the new definition of before48, following the analysis on http://www.mail-archive.com/dccp@vger.kernel.org/msg01295.html (1) Updating GSR when P.seqno >= S.SWL With the old definition we did not update when P.seqno and S.SWL are 2^47 apart. To ensure the same behaviour as with the old definition, this is replaced with the equivalent condition dccp_delta_seqno(S.SWL, P.seqno) >= 0 (2) Sending SYNC when P.seqno >= S.OSR Here it is debatable whether the new definition causes an ambiguity: the case is similar to (1); and to have consistency with the case (1), we use the equivalent condition dccp_delta_seqno(S.OSR, P.seqno) >= 0 Detailed Justification
2007-03-07[DCCP]: Revert patch which disables bidirectional modeGerrit Renker
This reverts an earlier patch which disabled bidirectional mode, meaning that a listening (passive) socket was not allowed to write to the other (active) end of the connection. This mode had been disabled when there were problems with CCID3, but it imposes a constraint on socket programming and thus hinders deployment. A change is included to ignore RX feedback received by the TX CCID3 module. Many thanks to Andre Noll for pointing out this issue. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-03-06[DCCP]: Correctly split CCID half connectionsGerrit Renker
This fixes a bug caused by a previous patch, which causes DCCP servers in LISTEN state to not receive packets. This patch changes the logic so that * servers in either LISTEN or OPEN state get the RX half connection packets * clients in OPEN state get the TX half connection packets Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-02-10[NET] DCCP: Fix whitespace errors.YOSHIFUJI Hideaki
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-11[DCCP]: Whitespace cleanupsArnaldo Carvalho de Melo
That accumulated over the last months hackaton, shame on me for not using git-apply whitespace helping hand, will do that from now on. Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2006-12-11[DCCP]: Only deliver to the CCID rx side in chargeGerrit Renker
This is an optimisation to reduce CPU load. The received feedback is now only directed to the active CCID component, without requiring processing also by the inactive one. As a consequence, a similar test in ccid3.c is now redundant and is also removed. Justification: Currently DCCP works as a unidirectional service, i.e. a listening server is not at the same time a connecting client. As far as I can see, several modifications are necessary until that becomes possible. At the present time, received feedback is both fed to the rx/tx CCID modules. In unidirectional service, only one of these is active at any one time. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2006-12-02[DCCP]: Simplified conditions due to use of enum:8 statesGerrit Renker
This reaps the benefit of the earlier patch, which changed the type of CCID 3 states to use enums, in that many conditions are now simplified and the number of possible (unexpected) values is greatly reduced. In a few instances, this also allowed to simplify pre-conditions; where care has been taken to retain logical equivalence. [DCCP]: Introduce a consistent BUG/WARN message scheme This refines the existing set of DCCP messages so that * BUG(), BUG_ON(), WARN_ON() have meaningful DCCP-specific counterparts * DCCP_CRIT (for severe warnings) is not rate-limited * DCCP_WARN() is introduced as rate-limited wrapper Using these allows a faster and cleaner transition to their original counterparts once the code has matured into a full DCCP implementation. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2006-12-02[DCCP]: Update code comments for Step 2/3Gerrit Renker
Sorts out the comments for processing steps 2,3 in section 8.5 of RFC 4340. All comments have been updated against this document, and the reference to step 2 has been made consistent throughout the files. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2006-10-24[DCCP]: Update documentation references.Gerrit Renker
Updates the references to spec documents throughout the code, taking into account that * the DCCP, CCID 2, and CCID 3 drafts all became RFCs in March this year * RFC 1063 was obsoleted by RFC 1191 * draft-ietf-tcpimpl-pmtud-0x.txt was published as an Informational RFC, RFC 2923 on 2000-09-22. All references verified. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-30Remove obsolete #include <linux/config.h>Jörn Engel
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-03-20[DCCP] minisock: Rename struct dccp_options to struct dccp_minisockArnaldo Carvalho de Melo
This will later be included in struct dccp_request_sock so that we can have per connection feature negotiation state while in the 3way handshake, when we clone the DCCP_ROLE_LISTEN socket (in dccp_create_openreq_child) we'll just copy this state from dreq_minisock to dccps_minisock. Also the feature negotiation and option parsing code will mostly touch dccps_minisock, which will simplify some stuff. Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20[DCCP]: Uninline some functionsArnaldo Carvalho de Melo
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20[DCCP]: Generalize dccp_v4_send_resetArnaldo Carvalho de Melo
Renaming it to dccp_send_reset and moving it from the ipv4 specific code to the core dccp code. This fixes some bugs in IPV6 where timers would send v4 resets, etc. Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20[DCCP] CCID: Improve CCID infrastructureArnaldo Carvalho de Melo
1. No need for ->ccid_init nor ->ccid_exit, this is what module_{init,exit} does and anynways neither ccid2 nor ccid3 were using it. 2. Rename struct ccid to struct ccid_operations and introduce struct ccid with a pointer to ccid_operations and rigth after it the rx or tx private state. 3. Remove the pointer to the state of the half connections from struct dccp_sock, now its derived thru ccid_priv() from the ccid pointer. Now we also can implement the setsockopt for changing the CCID easily as no ccid init routines can affect struct dccp_sock in any way that prevents other CCIDs from working if a CCID switch operation is asked by apps. Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20[DCCP]: Initial feature negotiation implementationAndrea Bittau
Still needs more work, but boots and doesn't crashes, even does some negotiation! 18:38:52.174934 127.0.0.1.43458 > 127.0.0.1.5001: request <change_l ack_ratio 2, change_r ccid 2, change_l ccid 2> 18:38:52.218526 127.0.0.1.5001 > 127.0.0.1.43458: response <nop, nop, change_l ack_ratio 2, confirm_r ccid 2 2, confirm_l ccid 2 2, confirm_r ack_ratio 2> 18:38:52.185398 127.0.0.1.43458 > 127.0.0.1.5001: <nop, confirm_r ack_ratio 2, ack_vector0 0x00, elapsed_time 212> :-) Signed-off-by: Andrea Bittau <a.bittau@cs.ucl.ac.uk> Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-03[DCCP]: Notify CCID only after ACK vectors have been processed.Andrea Bittau
The CCID should be notified of packet reception only when a packet is valid. Therefore, the ACK vector needs to be processed before notifying the CCID. Also, the CCID might need information provided by the ACK vector. Signed-off-by: Andrea Bittau <a.bittau@cs.ucl.ac.uk> Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-03[DCCP]: Send an ACK vector when ACKing a response packetAndrea Bittau
If ACK vectors are used, each packet with an ACK should contain an ACK vector. The only exception currently is response packets. It probably is not a good idea to store ACK vector state before the connection is completed (to help protect from syn floods). Signed-off-by: Andrea Bittau <a.bittau@cs.ucl.ac.uk> Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-03[DCCP]: Do not process a packet twice when it's not in state DCCP_OPEN.Andrea Bittau
When packets are received, the connection is either in DCCP_OPEN [fast-path] or it isn't. If it's not [e.g. DCCP_PARTOPEN] upper layers will perform sanity checks and parse options. If it is in DCCP_OPEN, dccp_rcv_established() will do it. It is important not to re-parse options in dccp_rcv_established() when it is not called from the fast-path. Else, fore example, the ack vector will be added twice and the CCID will see the packet twice. The solution is to always enfore sanity checks from the upper layers. When packets arrive in the fast-path, sanity checks will be performed before calling dccp_rcv_established(). Note(acme): I rewrote the patch to achieve the same result but keeping dccp_rcv_established with the previous semantics and having it split into __dccp_rcv_established, that doesn't does do any sanity check, code in state != DCCP_OPEN use this lighter version as they already do the sanity checks. Signed-off-by: Andrea Bittau <a.bittau@cs.ucl.ac.uk> Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-03[IP_SOCKGLUE]: Remove most of the tcp specific callsArnaldo Carvalho de Melo
As DCCP needs to be called in the same spots. Now we have a member in inet_sock (is_icsk), set at sock creation time from struct inet_protosw->flags (if INET_PROTOSW_ICSK is set, like for TCP and DCCP) to see if a struct sock instance is a inet_connection_sock for places like the ones in ip_sockglue.c (v4 and v6) where we previously were looking if sk_type was SOCK_STREAM, that is insufficient because we now use the same code for DCCP, that has sk_type SOCK_DCCP. Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-03[DCCP]: Prepare the AF agnostic core for the introduction of DCCPv6Arnaldo Carvalho de Melo
Basically exports a similar set of functions as the one exported by the non-AF specific TCP code. In the process moved some non-AF specific code from dccp_v4_connect to dccp_connect_init and moved the checksum verification from dccp_invalid_packet to dccp_v4_rcv, so as to use it in dccp_v6_rcv too. Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-03[DCCP]: Introduce dccp_ipv4_af_opsArnaldo Carvalho de Melo
And make the core DCCP code AF agnostic, just like TCP, now its time to work on net/dccp/ipv6.c, we are close to the end! Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-10-10[DCCP]: Transition from PARTOPEN to OPEN when receiving DATA packetsArnaldo Carvalho de Melo
Noticed by Andrea Bittau, that provided a patch that was modified to not transition from RESPOND to OPEN when receiving DATA packets. Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-09-18[DCCP]: Move the ack vector code to net/dccp/ackvec.[ch]Arnaldo Carvalho de Melo
Isolating it, that will be used when we introduce a CCID2 (TCP-Like) implementation. Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-09-16[DCCP]: More precisely set reset_code when sending RESET packetsArnaldo Carvalho de Melo
Moving the setting of DCCP_SKB_CB(skb)->dccpd_reset_code to the places where events happen that trigger sending a RESET packet. Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-09-13[DCCP]: Handle SYNC packets in dccp_rcv_state_processArnaldo Carvalho de Melo
Eliciting a SYNCACK in response, we were handling SYNC packets only in the DCCP_OPEN state, in dccp_rcv_established. Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2005-09-13[DCCP]: Check if already in the CLOSING state in dccp_rcv_closereqArnaldo Carvalho de Melo
It is possible to receive more than one CLOSEREQ packet if the CLOSE packet sent in response is somehow lost, change the state to DCCP_CLOSING only on the first CLOSEREQ packet received. Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2005-09-09[DCCP] Introduce dccp_timestampArnaldo Carvalho de Melo
To start the timestamps with 0.0ms, easing the integer maths in the CCIDs, this probably will be reworked to use the to be introduced struct timeval_offset infrastructure out of skb_get_timestamp, etc. Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2005-08-29[DCCP]: Initial dccp_poll implementationArnaldo Carvalho de Melo
Tested with a patched netcat, no horror stories so far 8) Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[DCCP]: Implement the CLOSING timerArnaldo Carvalho de Melo
So that we retransmit CLOSE/CLOSEREQ packets till they elicit an answer or we hit a timeout. Most of the machinery uses TCP approaches, this code has to be polished & audited, but this is better than we had before. Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[DCCP]: Fix printf format warnings on 64-bit.David S. Miller
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[DCCP]: Fix the ACK and SEQ window variables settingsArnaldo Carvalho de Melo
This is from a first audit, more eyeballs are more than welcome. Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[DCCP]: Give more info on Step 6 failure debug printkArnaldo Carvalho de Melo
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[DCCP]: Use LIMIT_NETDEBUG in some debugging printksArnaldo Carvalho de Melo
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[DCCP]: Send SYNCACK packets in response to SYNC packetsArnaldo Carvalho de Melo
Also fix step 6 when receiving SYNC or SYNCACK packets, i.e. we were not using the updated swl. Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>