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2008-09-04dccp: Deprecate Ack Ratio sysctlGerrit Renker
This patch deprecates the Ack Ratio sysctl, since * Ack Ratio is entirely ignored by CCID-3 and CCID-4, * Ack Ratio currently doesn't work in CCID-2 (i.e. is always set to 1); * even if it would work in CCID-2, there is no point for a user to change it: - Ack Ratio is constrained by cwnd (RFC 4341, 6.1.2), - if Ack Ratio > cwnd, the system resorts to spurious RTO timeouts (since waiting for Acks which will never arrive in this window), - cwnd is not a user-configurable value. The only reasonable place for Ack Ratio is to print it for debugging. It is planned to do this later on, as part of e.g. dccp_probe. With this patch Ack Ratio is now under full control of feature negotiation: * Ack Ratio is resolved as a dependency of the selected CCID; * if the chosen CCID supports it (i.e. CCID == CCID-2), Ack Ratio is set to the default of 2, following RFC 4340, 11.3 - "New connections start with Ack Ratio 2 for both endpoints"; * what happens then is part of another patch set, since it concerns the dynamic update of Ack Ratio while the connection is in full flight. Thanks to Tomasz Grobelny for discussion leading up to this patch. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2008-09-04dccp: Mechanism to resolve CCID dependenciesGerrit Renker
This adds a hook to resolve features whose value depends on the choice of CCID. It is done at the server since it can only be done after the CCID values have been negotiated; i.e. the client will add its CCID preference list on the Change options sent in the Request, which will be reconciled with the local preference list of the server. The concept is documented on http://www.erg.abdn.ac.uk/users/gerrit/dccp/notes/feature_negotiation/\ implementation_notes.html#ccid_dependencies Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
2008-09-04dccp: Resolve dependencies of features on choice of CCIDGerrit Renker
This provides a missing link in the code chain, as several features implicitly depend and/or rely on the choice of CCID. Most notably, this is the Send Ack Vector feature, but also Ack Ratio and Send Loss Event Rate (also taken care of). For Send Ack Vector, the situation is as follows: * since CCID2 mandates the use of Ack Vectors, there is no point in allowing endpoints which use CCID2 to disable Ack Vector features such a connection; * a peer with a TX CCID of CCID2 will always expect Ack Vectors, and a peer with a RX CCID of CCID2 must always send Ack Vectors (RFC 4341, sec. 4); * for all other CCIDs, the use of (Send) Ack Vector is optional and thus negotiable. However, this implies that the code negotiating the use of Ack Vectors also supports it (i.e. is able to supply and to either parse or ignore received Ack Vectors). Since this is not the case (CCID-3 has no Ack Vector support), the use of Ack Vectors is here disabled, with a comment in the source code. An analogous consideration arises for the Send Loss Event Rate feature, since the CCID-3 implementation does not support the loss interval options of RFC 4342. To make such use explicit, corresponding feature-negotiation options are inserted which signal the use of the loss event rate option, as it is used by the CCID3 code. Lastly, the values of the Ack Ratio feature are matched to the choice of CCID. The patch implements this as a function which is called after the user has made all other registrations for changing default values of features. The table is variable-length, the reserved (and hence for feature-negotiation invalid, confirmed by considering section 19.4 of RFC 4340) feature number `0' is used to mark the end of the table. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
2008-09-04dccp: Cleanup routines for feature negotiationGerrit Renker
This inserts the required de-allocation routines for memory allocated by feature negotiation in the socket destructors, replacing dccp_feat_clean() in one instance. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
2008-09-04dccp: Per-socket initialisation of feature negotiationGerrit Renker
This provides feature-negotiation initialisation for both DCCP sockets and DCCP request_sockets, to support feature negotiation during connection setup. It also resolves a FIXME regarding the congestion control initialisation. Thanks to Wei Yongjun for help with the IPv6 side of this patch. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
2008-08-06tcp: Fix kernel panic when calling tcp_v(4/6)_md5_do_lookupGui Jianfeng
If the following packet flow happen, kernel will panic. MathineA MathineB SYN ----------------------> SYN+ACK <---------------------- ACK(bad seq) ----------------------> When a bad seq ACK is received, tcp_v4_md5_do_lookup(skb->sk, ip_hdr(skb)->daddr)) is finally called by tcp_v4_reqsk_send_ack(), but the first parameter(skb->sk) is NULL at that moment, so kernel panic happens. This patch fixes this bug. OOPS output is as following: [ 302.812793] IP: [<c05cfaa6>] tcp_v4_md5_do_lookup+0x12/0x42 [ 302.817075] Oops: 0000 [#1] SMP [ 302.819815] Modules linked in: ipv6 loop dm_multipath rtc_cmos rtc_core rtc_lib pcspkr pcnet32 mii i2c_piix4 parport_pc i2c_core parport ac button ata_piix libata dm_mod mptspi mptscsih mptbase scsi_transport_spi sd_mod scsi_mod crc_t10dif ext3 jbd mbcache uhci_hcd ohci_hcd ehci_hcd [last unloaded: scsi_wait_scan] [ 302.849946] [ 302.851198] Pid: 0, comm: swapper Not tainted (2.6.27-rc1-guijf #5) [ 302.855184] EIP: 0060:[<c05cfaa6>] EFLAGS: 00010296 CPU: 0 [ 302.858296] EIP is at tcp_v4_md5_do_lookup+0x12/0x42 [ 302.861027] EAX: 0000001e EBX: 00000000 ECX: 00000046 EDX: 00000046 [ 302.864867] ESI: ceb69e00 EDI: 1467a8c0 EBP: cf75f180 ESP: c0792e54 [ 302.868333] DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068 [ 302.871287] Process swapper (pid: 0, ti=c0792000 task=c0712340 task.ti=c0746000) [ 302.875592] Stack: c06f413a 00000000 cf75f180 ceb69e00 00000000 c05d0d86 000016d0 ceac5400 [ 302.883275] c05d28f8 000016d0 ceb69e00 ceb69e20 681bf6e3 00001000 00000000 0a67a8c0 [ 302.890971] ceac5400 c04250a3 c06f413a c0792eb0 c0792edc cf59a620 cf59a620 cf59a634 [ 302.900140] Call Trace: [ 302.902392] [<c05d0d86>] tcp_v4_reqsk_send_ack+0x17/0x35 [ 302.907060] [<c05d28f8>] tcp_check_req+0x156/0x372 [ 302.910082] [<c04250a3>] printk+0x14/0x18 [ 302.912868] [<c05d0aa1>] tcp_v4_do_rcv+0x1d3/0x2bf [ 302.917423] [<c05d26be>] tcp_v4_rcv+0x563/0x5b9 [ 302.920453] [<c05bb20f>] ip_local_deliver_finish+0xe8/0x183 [ 302.923865] [<c05bb10a>] ip_rcv_finish+0x286/0x2a3 [ 302.928569] [<c059e438>] dev_alloc_skb+0x11/0x25 [ 302.931563] [<c05a211f>] netif_receive_skb+0x2d6/0x33a [ 302.934914] [<d0917941>] pcnet32_poll+0x333/0x680 [pcnet32] [ 302.938735] [<c05a3b48>] net_rx_action+0x5c/0xfe [ 302.941792] [<c042856b>] __do_softirq+0x5d/0xc1 [ 302.944788] [<c042850e>] __do_softirq+0x0/0xc1 [ 302.948999] [<c040564b>] do_softirq+0x55/0x88 [ 302.951870] [<c04501b1>] handle_fasteoi_irq+0x0/0xa4 [ 302.954986] [<c04284da>] irq_exit+0x35/0x69 [ 302.959081] [<c0405717>] do_IRQ+0x99/0xae [ 302.961896] [<c040422b>] common_interrupt+0x23/0x28 [ 302.966279] [<c040819d>] default_idle+0x2a/0x3d [ 302.969212] [<c0402552>] cpu_idle+0xb2/0xd2 [ 302.972169] ======================= [ 302.974274] Code: fc ff 84 d2 0f 84 df fd ff ff e9 34 fe ff ff 83 c4 0c 5b 5e 5f 5d c3 90 90 57 89 d7 56 53 89 c3 50 68 3a 41 6f c0 e8 e9 55 e5 ff <8b> 93 9c 04 00 00 58 85 d2 59 74 1e 8b 72 10 31 db 31 c9 85 f6 [ 303.011610] EIP: [<c05cfaa6>] tcp_v4_md5_do_lookup+0x12/0x42 SS:ESP 0068:c0792e54 [ 303.018360] Kernel panic - not syncing: Fatal exception in interrupt Signed-off-by: Gui Jianfeng <guijianfeng@cn.fujitsu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-26dccp: Allow to distinguish original and retransmitted packetsGerrit Renker
This patch allows the sender to distinguish original and retransmitted packets, which is in particular needed for the retransmission of DCCP-Requests: * the first Request uses ISS (generated in net/dccp/ip*.c), and sets GSS = ISS; * all retransmitted Requests use GSS' = GSS + 1, so that the n-th retransmitted Request has sequence number ISS + n (mod 48). To add generic support, the patch reorganises existing code so that: * icsk_retransmits == 0 for the original packet and * icsk_retransmits = n > 0 for the n-th retransmitted packet at the time dccp_transmit_skb() is called, via dccp_retransmit_skb(). Thanks to Wei Yongjun for pointing this problem out. Further changes: ---------------- * removed the `skb' argument from dccp_retransmit_skb(), since sk_send_head is used for all retransmissions (the exception is client-Acks in PARTOPEN state, but these do not use sk_send_head); * since sk_send_head always contains the original skb (via dccp_entail()), skb_cloned() never evaluated to true and thus pskb_copy() was never used. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
2008-07-25net: convert BUG_TRAP to generic WARN_ONIlpo Järvinen
Removes legacy reinvent-the-wheel type thing. The generic machinery integrates much better to automated debugging aids such as kerneloops.org (and others), and is unambiguous due to better naming. Non-intuively BUG_TRAP() is actually equal to WARN_ON() rather than BUG_ON() though some might actually be promoted to BUG_ON() but I left that to future. I could make at least one BUILD_BUG_ON conversion. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-13dccp ccid-3: Fix error in loss detectionGerrit Renker
The TFRC loss detection code used the wrong loss condition (RFC 4340, 7.7.1): * the difference between sequence numbers s1 and s2 instead of * the number of packets missing between s1 and s2 (one less than the distance). Since this condition appears in many places of the code, it has been put into a separate function, dccp_loss_free(). Further changes: ---------------- * tidied up incorrect typing (it was using `int' for u64/s64 types); * optimised conditional statements for common case of non-reordered packets; * rewrote comments/documentation to match the changes. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
2008-06-14net: change proto destroy method to return voidBrian Haley
Change struct proto destroy function pointer to return void. Noticed by Al Viro. Signed-off-by: Brian Haley <brian.haley@hp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-14Merge branch 'master' of ↵David S. Miller
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: drivers/net/ehea/ehea_main.c drivers/net/wireless/iwlwifi/Kconfig drivers/net/wireless/rt2x00/rt61pci.c net/ipv4/inet_timewait_sock.c net/ipv6/raw.c net/mac80211/ieee80211_sta.c
2008-04-12[DCCP]: Fix skb->cb conflicts with IPPatrick McHardy
dev_queue_xmit() and the other IP output functions expect to get a skb with clear or properly initialized skb->cb. Unlike TCP and UDP, the dccp_skb_cb doesn't contain a struct inet_skb_parm at the beginning, so the DCCP-specific data is interpreted by the IP output functions. This can cause false negatives for the conditional POST_ROUTING hook invocation, making the packet bypass the hook. Add a inet_skb_parm/inet6_skb_parm union to the beginning of dccp_skb_cb to avoid clashes. Also add a BUILD_BUG_ON to make sure it fits in the cb. [ Combined with patch from Gerrit Renker to remove two now unnecessary memsets of IPCB(skb)->opt ] Signed-off-by: Patrick McHardy <kaber@trash.net> Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-03[DCCP]: Replace socket with sock for reset sending.Denis V. Lunev
Replace dccp_v(4|6)_ctl_socket with sock to unify a code with TCP/ICMP. Signed-off-by: Denis V. Lunev <den@openvz.org> Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-05net: replace remaining __FUNCTION__ occurrencesHarvey Harrison
__FUNCTION__ is gcc-specific, use __func__ Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-02-03[SOCK] proto: Add hashinfo member to struct protoArnaldo Carvalho de Melo
This way we can remove TCP and DCCP specific versions of sk->sk_prot->get_port: both v4 and v6 use inet_csk_get_port sk->sk_prot->hash: inet_hash is directly used, only v6 need a specific version to deal with mapped sockets sk->sk_prot->unhash: both v4 and v6 use inet_hash directly struct inet_connection_sock_af_ops also gets a new member, bind_conflict, so that inet_csk_get_port can find the per family routine. Now only the lookup routines receive as a parameter a struct inet_hashtable. With this we further reuse code, reducing the difference among INET transport protocols. Eventually work has to be done on UDP and SCTP to make them share this infrastructure and get as a bonus inet_diag interfaces so that iproute can be used with these protocols. net-2.6/net/ipv4/inet_hashtables.c: struct proto | +8 struct inet_connection_sock_af_ops | +8 2 structs changed __inet_hash_nolisten | +18 __inet_hash | -210 inet_put_port | +8 inet_bind_bucket_create | +1 __inet_hash_connect | -8 5 functions changed, 27 bytes added, 218 bytes removed, diff: -191 net-2.6/net/core/sock.c: proto_seq_show | +3 1 function changed, 3 bytes added, diff: +3 net-2.6/net/ipv4/inet_connection_sock.c: inet_csk_get_port | +15 1 function changed, 15 bytes added, diff: +15 net-2.6/net/ipv4/tcp.c: tcp_set_state | -7 1 function changed, 7 bytes removed, diff: -7 net-2.6/net/ipv4/tcp_ipv4.c: tcp_v4_get_port | -31 tcp_v4_hash | -48 tcp_v4_destroy_sock | -7 tcp_v4_syn_recv_sock | -2 tcp_unhash | -179 5 functions changed, 267 bytes removed, diff: -267 net-2.6/net/ipv6/inet6_hashtables.c: __inet6_hash | +8 1 function changed, 8 bytes added, diff: +8 net-2.6/net/ipv4/inet_hashtables.c: inet_unhash | +190 inet_hash | +242 2 functions changed, 432 bytes added, diff: +432 vmlinux: 16 functions changed, 485 bytes added, 492 bytes removed, diff: -7 /home/acme/git/net-2.6/net/ipv6/tcp_ipv6.c: tcp_v6_get_port | -31 tcp_v6_hash | -7 tcp_v6_syn_recv_sock | -9 3 functions changed, 47 bytes removed, diff: -47 /home/acme/git/net-2.6/net/dccp/proto.c: dccp_destroy_sock | -7 dccp_unhash | -179 dccp_hash | -49 dccp_set_state | -7 dccp_done | +1 5 functions changed, 1 bytes added, 242 bytes removed, diff: -241 /home/acme/git/net-2.6/net/dccp/ipv4.c: dccp_v4_get_port | -31 dccp_v4_request_recv_sock | -2 2 functions changed, 33 bytes removed, diff: -33 /home/acme/git/net-2.6/net/dccp/ipv6.c: dccp_v6_get_port | -31 dccp_v6_hash | -7 dccp_v6_request_recv_sock | +5 3 functions changed, 5 bytes added, 38 bytes removed, diff: -33 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[DCCP]: Remove unused inline functionGerrit Renker
The function follows48(), which is a special-case of dccp_delta_seqno(), is nowhere used in the DCCP code, thus removed by this patch. 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]: Support inserting options during the 3-way handshakeGerrit Renker
This provides a separate routine to insert options during the initial handshake. The main purpose is to conduct feature negotiation, for the moment the only user is the timestamp echo needed for the (CCID3) handshake RTT sample. Padding of options has been put into a small separate routine, to be shared among the two functions. This could also be used as a generic routine to finish inserting options. Also removed an `XXX' comment since its content was obvious. 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]: Use maximum-RTO backoff from DCCP specGerrit Renker
This removes another Fixme, using the TCP maximum RTO rather than the value specified by the DCCP specification. Across the sections in RFC 4340, 64 seconds is consistently suggested as maximum RTO backoff value; and this is the value which is now used. I have checked both termination cases for retransmissions of Close/CloseReq: with the default value 15 of `retries2', and an initial icsk_retransmit = 0, it takes about 614 seconds to declare a non-responding peer as dead, after which the final terminating Reset is sent. With the TCP maximum RTO value of 120 seconds it takes (as might be expected) almost twice as long, about 23 minutes. 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[CCID3]: Interface CCID3 code with newer Loss Intervals DatabaseGerrit Renker
This hooks up the TFRC Loss Interval database with CCID 3 packet reception. In addition, it makes the CCID-specific computation of the first loss interval (which requires access to all the guts of CCID3) local to ccid3.c. The patch also fixes an omission in the DCCP code, that of a default / fallback RTT value (defined in section 3.4 of RFC 4340 as 0.2 sec); while at it, the upper bound of 4 seconds for an RTT sample has been reduced to match the initial TCP RTO value of 3 seconds from[RFC 1122, 4.2.3.1]. 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]: Introduce generic function to test for `data packets'Gerrit Renker
as per RFC 4340, sec. 7.7. 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>
2007-10-10[DCCP]: Factor out common code for generating ResetsGerrit Renker
This factors code common to dccp_v{4,6}_ctl_send_reset into a separate function, and adds support for filling in the Data 1 ... Data 3 fields from RFC 4340, 5.6. It is useful to have this separate, since the following Reset codes will always be generated from the control socket rather than via dccp_send_reset: * Code 3, "No Connection", cf. 8.3.1; * Code 4, "Packet Error" (identification for Data 1 added); * Code 5, "Option Error" (identification for Data 1..3 added, will be used later); * Code 6, "Mandatory Error" (same as Option Error); * Code 7, "Connection Refused" (what on Earth is the difference to "No Connection"?); * Code 8, "Bad Service Code"; * Code 9, "Too Busy"; * Code 10, "Bad Init Cookie" (not used). Code 0 is not recommended by the RFC, the following codes would be used in dccp_send_reset() instead, since they all relate to an established DCCP connection: * Code 1, "Closed"; * Code 2, "Aborted"; * Code 11, "Aggression Penalty" (12.3). Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.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]: Add Support for Data 1 .. 3 fields of Reset packetsGerrit Renker
This adds fields to support the informational Data 1..3 fields of the DCCP-Reset packets (RFC 4340, 5.6), and makes minor cosmetic changes to documentation. Code which fills in these fields follows in subsequent patches, it is primarily used for reporting option-processing and feature-negotiation errors. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
2007-10-10[DCCP]: Add FIXME for send_delayed_ackGerrit Renker
This adds a FIXME to signal that the function dccp_send_delayed_ack is nowhere used in the entire DCCP/CCID code. Using a delayed Ack timer is suggested in 11.3 of RFC 4340, but it has also rather subtle implications for the Ack-Ratio-accounting. CCID2 does not use this (maybe it should). I think leaving the function in is good, in case someone wants to implement this. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.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]: Provide 10s of microsecond timesourceGerrit Renker
This provides a timesource, conveniently used for DCCP timestamps, which returns the elapsed time in 10s of microseconds since initialisation. This makes for a wrap-around time of about 11.9 hours, which should be sufficient for most applications. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[DCCP]: Nuke the timeval helpers now that we fully converted 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>
2007-10-10[DCCP]: Nuke dccp_timestamp and dccps_epoch, not used anymoreArnaldo Carvalho de Melo
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>
2007-07-10Fix dccp_sum_coverageIan McDonald
When compiling with EXTRA_CFLAGS=-W notice that we have signed/unsigned issue in dccp.h. Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
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]: Always use debug-toggle parametersGerrit Renker
Currently debugging output (when configured) is automatically enabled when DCCP modules are compiled into the kernel rather than built as loadable modules. This is not necessary, since the module parameters in this case become kernel commandline parameters, e.g. DCCP or CCID3 debug output can be enabled for a static build by appending the following at the boot prompt: dccp.dccp_debug=1 dccp_ccid3.ccid3_debug=1 This patch therefore does away with the more complicated way of always enabling debug output for static builds 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>
2007-04-25[DCCP]: Fix for follows48Gerrit Renker
The follows48 relation identifies whether 48-bit sequence number x is the direct successor of y. Currently, it does not handle cases of the following type correctly: follows48(0x(prefix)10000LL, 0x(prefix)0FFFFLL) where prefix is an arbitrary hex sequence of up to 7 digits. This is fixed by reusing the new dccp_delta_seqno function. 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> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[DCCP]: Make `before' relation unambiguousGerrit Renker
Problem:
2007-04-25[DCCP]: Make dccp_delta_seqno return signed numbersGerrit Renker
Problem:
2007-04-25[DCCP]: 48-bit sequence number arithmeticGerrit Renker
This patch * organizes the sequence arithmetic functions into one corner of dccp.h * performs a small modification of dccp_set_seqno to make it more widely reusable (now it is safe to use any number, since it performs modulo-2^48 assignment) * adds functions and generic macros for 48-bit sequence arithmetic: --48 bit complement --modulo-48 addition and modulo-48 subtraction --dccp_inc_seqno now a special case of add48 Constants renamed following a suggestion by Arnaldo. 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> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-03-25[DCCP]: make dccp_write_xmit_timer() static againAdrian Bunk
dccp_write_xmit_timer() needlessly became global. Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-03-09[DCCP]: Initialise write_xmit_timer also on passive socketsGerrit Renker
The TX CCID needs the write_xmit_timer for delaying packet sends. Previously this timer was only activated on active (connecting) sockets. This patch initialises the write_xmit_timer in sync with the other timers, i.e. the timer will be ready on any socket. This is used by applications with a listening socket which start to stream after receiving an initiation by the client. The write_xmit_timer is stopped when the application closes, as before. Was tested to work and to remove the timer bug reported on dccp@vger. Also moved timer initialisation into timer.c (static). Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz> 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]: Debug timeval operationsGerrit Renker
Problem: Most target types in the CCID3 code are u32, so subtle conversion errors can occur if signed time calculations yield negative results: the original values are lost in the conversion to unsigned, calculation errors go undetected. This patch therefore * sets all critical time types from unsigned to suseconds_t * avoids comparison between signed/unsigned via type-casting * provides ample warning messages in case time calculations are negative These warning messages can be removed at a later stage when the code has undergone more testing. 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>
2006-12-11[DCCP]: Remove timeo from output.cIan McDonald
It simplifies waiting for the CCID module to signal that a packet is ready to be sent. Other simplifications flow on from this such as removing constants. As a result of this EAGAIN is not returned any more by dccp_wait_for_ccid (which would otherwise lead to unnecessarily discarding the packet in dccp_write_xmit). Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> 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]: Set TX Queue Length Bounds via SysctlIan McDonald
Previously the transmit queue was unbounded. This patch: * puts a limit on transmit queue length and sends back EAGAIN if the buffer is full * sets the TX queue length to a sensible default * implements tx buffer sysctls for DCCP Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2006-12-02[DCCP]: enable debug messages also for static buildsGerrit Renker
This patch * makes debugging (when configured) work both for static / module build * provides generic debugging macros for use in other DCCP / CCID modules * adds missing information about debug parameters to Kconfig * performs some code tidy-up Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2006-12-02[DCCP]: Introduce DCCP_{BUG{_ON},CRIT} macros, use enum:8 for the ccid3 statesGerrit Renker
This patch tackles the following problem: * the ccid3_hc_{t,r}x_sock define ccid3hc{t,r}x_state as `u8', but in reality there can only be a few, pre-defined enum names * this necessitates addiditional checking for unexpected values which would otherwise be caught by the compiler Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2006-12-02[DCCP]: Introduce a consistent naming scheme for sysctlsGerrit Renker
In order to make their function clearer and obtain a consistent naming scheme to identify sysctls, all existing DCCP sysctls have been prefixed with `sysctl_dccp', following the same convention as used by TCP. Feature-specific sysctls retain the `feat' in the middle, although the `default' has been dropped, since it is obvious from use. Also removed a duplicate `dccp_feat_default_sequence_window' in ipv4.c. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2006-12-02[DCCP]: Add sysctls to control retransmission behaviourGerrit Renker
This adds 3 sysctls which govern the retransmission behaviour of DCCP control packets (3way handshake, feature negotiation). It removes 4 FIXMEs from the code. The close resemblance of sysctl variables to their TCP analogues is emphasised not only by their name, but also by giving them the same initial values. This is useful since there is not much practical experience with DCCP yet. Furthermore, with regard to the previous patch, it is now possible to limit the number of keepalive-Responses by setting net.dccp.default.request_retries (also a bit like in TCP). Lastly, added documentation of all existing DCCP sysctls. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2006-12-02[DCCP]: Support for partial checksums (RFC 4340, sec. 9.2)Gerrit Renker
This patch does the following: a) introduces variable-length checksums as specified in [RFC 4340, sec. 9.2] b) provides necessary socket options and documentation as to how to use them c) basic support and infrastructure for the Minimum Checksum Coverage feature [RFC 4340, sec. 9.2.1]: acceptability tests, user notification and user interface In addition, it (1) fixes two bugs in the DCCPv4 checksum computation: * pseudo-header used checksum_len instead of skb->len * incorrect checksum coverage calculation based on dccph_x (2) removes dccp_v4_verify_checksum() since it reduplicates code of the checksum computation; code calling this function is updated accordingly. (3) now uses skb_checksum(), which is safer than checksum_partial() if the sk_buff has is a non-linear buffer (has pages attached to it). (4) fixes an outstanding TODO item: * If P.CsCov is too large for the packet size, drop packet and return. The code has been tested with applications, the latest version of tcpdump now comes with support for partial DCCP checksums. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2006-12-02[DCCP]: tidy up dccp_v{4,6}_conn_requestGerrit Renker
This is a code simplification to remove reduplicated code by concentrating and abstracting shared code. Detailed Changes:
2006-12-02[DCCP]: Fix logfile overflowIan McDonald
This patch fixes data being spewed into the logs continually. As the code stood if there was a large queue and long delays timeo would go down to zero and never get reset. This fixes it by resetting timeo. Put constant into header as well. Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>