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2010-03-19TCP: check min TTL on received ICMP packetsstephen hemminger
This adds RFC5082 checks for TTL on received ICMP packets. It adds some security against spoofed ICMP packets disrupting GTSM protected sessions. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-10tcp: Fix tcp_v4_rcv()Eric Dumazet
Commit d218d111 (tcp: Generalized TTL Security Mechanism) added a bug for TIMEWAIT sockets. We should not test min_ttl for TW sockets. Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Acked-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-08tcp: Add SNMP counters for backlog and min_ttl dropsEric Dumazet
Commit 6b03a53a (tcp: use limited socket backlog) added the possibility of dropping frames when backlog queue is full. Commit d218d111 (tcp: Generalized TTL Security Mechanism) added the possibility of dropping frames when TTL is under a given limit. This patch adds new SNMP MIB entries, named TCPBacklogDrop and TCPMinTTLDrop, published in /proc/net/netstat in TcpExt: line netstat -s | egrep "TCPBacklogDrop|TCPMinTTLDrop" TCPBacklogDrop: 0 TCPMinTTLDrop: 0 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-05net: backlog functions renameZhu Yi
sk_add_backlog -> __sk_add_backlog sk_add_backlog_limited -> sk_add_backlog Signed-off-by: Zhu Yi <yi.zhu@intel.com> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-05tcp: use limited socket backlogZhu Yi
Make tcp adapt to the limited socket backlog change. Cc: "David S. Miller" <davem@davemloft.net> Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> Cc: "Pekka Savola (ipv6)" <pekkas@netcore.fi> Cc: Patrick McHardy <kaber@trash.net> Signed-off-by: Zhu Yi <yi.zhu@intel.com> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-01-17net: spread __net_init, __net_exitAlexey Dobriyan
__net_init/__net_exit are apparently not going away, so use them to full extent. In some cases __net_init was removed, because it was called from __net_exit code. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-01-17tcp: account SYN-ACK timeouts & retransmissionsOctavian Purdila
Currently we don't increment SYN-ACK timeouts & retransmissions although we do increment the same stats for SYN. We seem to have lost the SYN-ACK accounting with the introduction of tcp_syn_recv_timer (commit 2248761e in the netdev-vger-cvs tree). This patch fixes this issue. In the process we also rename the v4/v6 syn/ack retransmit functions for clarity. We also add a new request_socket operations (syn_ack_timeout) so we can keep code in inet_connection_sock.c protocol agnostic. Signed-off-by: Octavian Purdila <opurdila@ixiacom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-01-11tcp: Generalized TTL Security MechanismStephen Hemminger
This patch adds the kernel portions needed to implement RFC 5082 Generalized TTL Security Mechanism (GTSM). It is a lightweight security measure against forged packets causing DoS attacks (for BGP). This is already implemented the same way in BSD kernels. For the necessary Quagga patch http://www.gossamer-threads.com/lists/quagga/dev/17389 Description from Cisco http://www.cisco.com/en/US/docs/ios/12_3t/12_3t7/feature/guide/gt_btsh.html It does add one byte to each socket structure, but I did a little rearrangement to reuse a hole (on 64 bit), but it does grow the structure on 32 bit This should be documented on ip(4) man page and the Glibc in.h file also needs update. IPV6_MINHOPLIMIT should also be added (although BSD doesn't support that). Only TCP is supported, but could also be added to UDP, DCCP, SCTP if desired. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-12-15tcp: Revert per-route SACK/DSACK/TIMESTAMP changes.David S. Miller
It creates a regression, triggering badness for SYN_RECV sockets, for example: [19148.022102] Badness at net/ipv4/inet_connection_sock.c:293 [19148.022570] NIP: c02a0914 LR: c02a0904 CTR: 00000000 [19148.023035] REGS: eeecbd30 TRAP: 0700 Not tainted (2.6.32) [19148.023496] MSR: 00029032 <EE,ME,CE,IR,DR> CR: 24002442 XER: 00000000 [19148.024012] TASK = eee9a820[1756] 'privoxy' THREAD: eeeca000 This is likely caused by the change in the 'estab' parameter passed to tcp_parse_options() when invoked by the functions in net/ipv4/tcp_minisocks.c But even if that is fixed, the ->conn_request() changes made in this patch series is fundamentally wrong. They try to use the listening socket's 'dst' to probe the route settings. The listening socket doesn't even have a route, and you can't get the right route (the child request one) until much later after we setup all of the state, and it must be done by hand. This stuff really isn't ready, so the best thing to do is a full revert. This reverts the following commits: f55017a93f1a74d50244b1254b9a2bd7ac9bbf7d 022c3f7d82f0f1c68018696f2f027b87b9bb45c2 1aba721eba1d84a2defce45b950272cee1e6c72a cda42ebd67ee5fdf09d7057b5a4584d36fe8a335 345cda2fd695534be5a4494f1b59da9daed33663 dc343475ed062e13fc260acccaab91d7d80fd5b2 05eaade2782fb0c90d3034fd7a7d5a16266182bb 6a2a2d6bf8581216e08be15fcb563cfd6c430e1e Signed-off-by: David S. Miller <davem@davemloft.net>
2009-12-08tcp: Fix a connect() race with timewait socketsEric Dumazet
First patch changes __inet_hash_nolisten() and __inet6_hash() to get a timewait parameter to be able to unhash it from ehash at same time the new socket is inserted in hash. This makes sure timewait socket wont be found by a concurrent writer in __inet_check_established() Reported-by: kapil dakhane <kdakhane@gmail.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-12-03tcp: diag: Dont report negative values for rx queueEric Dumazet
Both netlink and /proc/net/tcp interfaces can report transient negative values for rx queue. ss -> State Recv-Q Send-Q Local Address:Port Peer Address:Port ESTAB -6 6 127.0.0.1:45956 127.0.0.1:3333 netstat -> tcp 4294967290 6 127.0.0.1:37784 127.0.0.1:3333 ESTABLISHED This is because we dont lock socket while computing tp->rcv_nxt - tp->copied_seq, and another CPU can update copied_seq before rcv_next in RX path. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-12-03net: Batch inet_twsk_purgeEric W. Biederman
This function walks the whole hashtable so there is no point in passing it a network namespace. Instead I purge all timewait sockets from dead network namespaces that I find. If the namespace is one of the once I am trying to purge I am guaranteed no new timewait sockets can be formed so this will get them all. If the namespace is one I am not acting for it might form a few more but I will call inet_twsk_purge again and shortly to get rid of them. In any even if the network namespace is dead timewait sockets are useless. Move the calls of inet_twsk_purge into batch_exit routines so that if I am killing a bunch of namespaces at once I will just call inet_twsk_purge once and save a lot of redundant unnecessary work. My simple 4k network namespace exit test the cleanup time dropped from roughly 8.2s to 1.6s. While the time spent running inet_twsk_purge fell to about 2ms. 1ms for ipv4 and 1ms for ipv6. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-12-02TCPCT part 1g: Responder Cookie => InitiatorWilliam Allen Simpson
Parse incoming TCP_COOKIE option(s). Calculate <SYN,ACK> TCP_COOKIE option. Send optional <SYN,ACK> data. This is a significantly revised implementation of an earlier (year-old) patch that no longer applies cleanly, with permission of the original author (Adam Langley): http://thread.gmane.org/gmane.linux.network/102586 Requires: TCPCT part 1a: add request_values parameter for sending SYNACK TCPCT part 1b: generate Responder Cookie secret TCPCT part 1c: sysctl_tcp_cookie_size, socket option TCP_COOKIE_TRANSACTIONS TCPCT part 1d: define TCP cookie option, extend existing struct's TCPCT part 1e: implement socket option TCP_COOKIE_TRANSACTIONS TCPCT part 1f: Initiator Cookie => Responder Signed-off-by: William.Allen.Simpson@gmail.com Signed-off-by: David S. Miller <davem@davemloft.net>
2009-12-02TCPCT part 1d: define TCP cookie option, extend existing struct'sWilliam Allen Simpson
Data structures are carefully composed to require minimal additions. For example, the struct tcp_options_received cookie_plus variable fits between existing 16-bit and 8-bit variables, requiring no additional space (taking alignment into consideration). There are no additions to tcp_request_sock, and only 1 pointer in tcp_sock. This is a significantly revised implementation of an earlier (year-old) patch that no longer applies cleanly, with permission of the original author (Adam Langley): http://thread.gmane.org/gmane.linux.network/102586 The principle difference is using a TCP option to carry the cookie nonce, instead of a user configured offset in the data. This is more flexible and less subject to user configuration error. Such a cookie option has been suggested for many years, and is also useful without SYN data, allowing several related concepts to use the same extension option. "Re: SYN floods (was: does history repeat itself?)", September 9, 1996. http://www.merit.net/mail.archives/nanog/1996-09/msg00235.html "Re: what a new TCP header might look like", May 12, 1998. ftp://ftp.isi.edu/end2end/end2end-interest-1998.mail These functions will also be used in subsequent patches that implement additional features. Requires: TCPCT part 1a: add request_values parameter for sending SYNACK TCPCT part 1b: generate Responder Cookie secret TCPCT part 1c: sysctl_tcp_cookie_size, socket option TCP_COOKIE_TRANSACTIONS Signed-off-by: William.Allen.Simpson@gmail.com Signed-off-by: David S. Miller <davem@davemloft.net>
2009-12-02TCPCT part 1a: add request_values parameter for sending SYNACKWilliam Allen Simpson
Add optional function parameters associated with sending SYNACK. These parameters are not needed after sending SYNACK, and are not used for retransmission. Avoids extending struct tcp_request_sock, and avoids allocating kernel memory. Also affects DCCP as it uses common struct request_sock_ops, but this parameter is currently reserved for future use. Signed-off-by: William.Allen.Simpson@gmail.com Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-11-13inetpeer: Optimize inet_getid()Eric Dumazet
While investigating for network latencies, I found inet_getid() was a contention point for some workloads, as inet_peer_idlock is shared by all inet_getid() users regardless of peers. One way to fix this is to make ip_id_count an atomic_t instead of __u16, and use atomic_add_return(). In order to keep sizeof(struct inet_peer) = 64 on 64bit arches tcp_ts_stamp is also converted to __u32 instead of "unsigned long". Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-11-13net: TCP_MSS_DEFAULT, TCP_MSS_DESIREDWilliam Allen Simpson
Define two symbols needed in both kernel and user space. Remove old (somewhat incorrect) kernel variant that wasn't used in most cases. Default should apply to both RMSS and SMSS (RFC2581). Replace numeric constants with defined symbols. Stand-alone patch, originally developed for TCPCT. Signed-off-by: William.Allen.Simpson@gmail.com Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-10-29Allow tcp_parse_options to consult dst entryGilad Ben-Yossef
We need tcp_parse_options to be aware of dst_entry to take into account per dst_entry TCP options settings Signed-off-by: Gilad Ben-Yossef <gilad@codefidence.com> Sigend-off-by: Ori Finkelman <ori@comsleep.com> Sigend-off-by: Yony Amit <yony@comsleep.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-10-18inet: rename some inet_sock fieldsEric Dumazet
In order to have better cache layouts of struct sock (separate zones for rx/tx paths), we need this preliminary patch. Goal is to transfert fields used at lookup time in the first read-mostly cache line (inside struct sock_common) and move sk_refcnt to a separate cache line (only written by rx path) This patch adds inet_ prefix to daddr, rcv_saddr, dport, num, saddr, sport and id fields. This allows a future patch to define these fields as macros, like sk_refcnt, without name clashes. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-10-13tcp: replace ehash_size by ehash_maskEric Dumazet
Storing the mask (size - 1) instead of the size allows fast path to be a bit faster. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-15tcp: fix ssthresh u16 leftoverIlpo Järvinen
It was once upon time so that snd_sthresh was a 16-bit quantity. ...That has not been true for long period of time. I run across some ancient compares which still seem to trust such legacy. Put all that magic into a single place, I hopefully found all of them. Compile tested, though linking of allyesconfig is ridiculous nowadays it seems. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-02tcp: replace hard coded GFP_KERNEL with sk_allocationWu Fengguang
This fixed a lockdep warning which appeared when doing stress memory tests over NFS: inconsistent {RECLAIM_FS-ON-W} -> {IN-RECLAIM_FS-W} usage. page reclaim => nfs_writepage => tcp_sendmsg => lock sk_lock mount_root => nfs_root_data => tcp_close => lock sk_lock => tcp_send_fin => alloc_skb_fclone => page reclaim David raised a concern that if the allocation fails in tcp_send_fin(), and it's GFP_ATOMIC, we are going to yield() (which sleeps) and loop endlessly waiting for the allocation to succeed. But fact is, the original GFP_KERNEL also sleeps. GFP_ATOMIC+yield() looks weird, but it is no worse the implicit sleep inside GFP_KERNEL. Both could loop endlessly under memory pressure. CC: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> CC: David S. Miller <davem@davemloft.net> CC: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-02inet: inet_connection_sock_af_ops constStephen Hemminger
The function block inet_connect_sock_af_ops contains no data make it constant. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-02tcp: MD5 operations should be constStephen Hemminger
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-01Revert Backoff [v3]: Revert RTO on ICMP destination unreachableDamian Lukowski
Here, an ICMP host/network unreachable message, whose payload fits to TCP's SND.UNA, is taken as an indication that the RTO retransmission has not been lost due to congestion, but because of a route failure somewhere along the path. With true congestion, a router won't trigger such a message and the patched TCP will operate as standard TCP. This patch reverts one RTO backoff, if an ICMP host/network unreachable message, whose payload fits to TCP's SND.UNA, arrives. Based on the new RTO, the retransmission timer is reset to reflect the remaining time, or - if the revert clocked out the timer - a retransmission is sent out immediately. Backoffs are only reverted, if TCP is in RTO loss recovery, i.e. if there have been retransmissions and reversible backoffs, already. Changes from v2: 1) Renaming of skb in tcp_v4_err() moved to another patch. 2) Reintroduced tcp_bound_rto() and __tcp_set_rto(). 3) Fixed code comments. Signed-off-by: Damian Lukowski <damian@tvk.rwth-aachen.de> Acked-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-01Revert Backoff [v3]: Rename skb to icmp_skb in tcp_v4_err()Damian Lukowski
This supplementary patch renames skb to icmp_skb in tcp_v4_err() in order to disambiguate from another sk_buff variable, which will be introduced in a separate patch. Signed-off-by: Damian Lukowski <damian@tvk.rwth-aachen.de> Acked-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-07-20tcp: Use correct peer adr when copying MD5 keysJohn Dykstra
When the TCP connection handshake completes on the passive side, a variety of state must be set up in the "child" sock, including the key if MD5 authentication is being used. Fix TCP for both address families to label the key with the peer's destination address, rather than the address from the listening sock, which is usually the wildcard. Reported-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: John Dykstra <john.dykstra1@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-07-20tcp: Fix MD5 signature checking on IPv4 mapped socketsJohn Dykstra
Fix MD5 signature checking so that an IPv4 active open to an IPv6 socket can succeed. In particular, use the correct address family's signature generation function for the SYN/ACK. Reported-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: John Dykstra <john.dykstra1@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-06-03net: skb->dst accessorsEric Dumazet
Define three accessors to get/set dst attached to a skb struct dst_entry *skb_dst(const struct sk_buff *skb) void skb_dst_set(struct sk_buff *skb, struct dst_entry *dst) void skb_dst_drop(struct sk_buff *skb) This one should replace occurrences of : dst_release(skb->dst) skb->dst = NULL; Delete skb->dst field Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-06-03net: skb->rtable accessorEric Dumazet
Define skb_rtable(const struct sk_buff *skb) accessor to get rtable from skb Delete skb->rtable field Setting rtable is not allowed, just set dst instead as rtable is an alias. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-05tcp:fix the code indentShan Wei
Signed-off-by: Shan Wei<shanwei@cn.fujitsu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-27gro: Fix COMPLETE checksum handlingHerbert Xu
On a brand new GRO skb, we cannot call ip_hdr since the header may lie in the non-linear area. This patch adds the helper skb_gro_network_header to handle this. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-03-28lsm: Relocate the IPv4 security_inet_conn_request() hooksPaul Moore
The current placement of the security_inet_conn_request() hooks do not allow individual LSMs to override the IP options of the connection's request_sock. This is a problem as both SELinux and Smack have the ability to use labeled networking protocols which make use of IP options to carry security attributes and the inability to set the IP options at the start of the TCP handshake is problematic. This patch moves the IPv4 security_inet_conn_request() hooks past the code where the request_sock's IP options are set/reset so that the LSM can safely manipulate the IP options as needed. This patch intentionally does not change the related IPv6 hooks as IPv6 based labeling protocols which use IPv6 options are not currently implemented, once they are we will have a better idea of the correct placement for the IPv6 hooks. Signed-off-by: Paul Moore <paul.moore@hp.com> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: James Morris <jmorris@namei.org>
2009-03-11tcp: allow timestamps even if SYN packet has tsval=0Eric Dumazet
Some systems send SYN packets with apparently wrong RFC1323 timestamp option values [timestamp tsval=0 tsecr=0]. It might be for security reasons (http://www.secuobs.com/plugs/25220.shtml ) Linux TCP stack ignores this option and sends back a SYN+ACK packet without timestamp option, thus many TCP flows cannot use timestamps and lose some benefit of RFC1323. Other operating systems seem to not care about initial tsval value, and let tcp flows to negotiate timestamp option. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-22tcp: Like icmp use register_pernet_subsysEric W. Biederman
To remove the possibility of packets flying around when network devices are being cleaned up use reisger_pernet_subsys instead of register_pernet_device. Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com> Acked-by: Denis V. Lunev <den@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-29gro: Avoid copying headers of unmerged packetsHerbert Xu
Unfortunately simplicity isn't always the best. The fraginfo interface turned out to be suboptimal. The problem was quite obvious. For every packet, we have to copy the headers from the frags structure into skb->head, even though for 99% of the packets this part is immediately thrown away after the merge. LRO didn't have this problem because it directly read the headers from the frags structure. This patch attempts to address this by creating an interface that allows GRO to access the headers in the first frag without having to copy it. Because all drivers that use frags place the headers in the first frag this optimisation should be enough. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-06net_dma: convert to dma_find_channelDan Williams
Use the general-purpose channel allocation provided by dmaengine. Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2008-12-29net: Fix percpu counters deadlockHerbert Xu
When we converted the protocol atomic counters such as the orphan count and the total socket count deadlocks were introduced due to the mismatch in BH status of the spots that used the percpu counter operations. Based on the diagnosis and patch by Peter Zijlstra, this patch fixes these issues by disabling BH where we may be in process context. Reported-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Tested-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15tcp: Add GRO supportHerbert Xu
This patch adds the TCP-specific portion of GRO. The criterion for merging is extremely strict (the TCP header must match exactly apart from the checksum) so as to allow refragmentation. Otherwise this is pretty much identical to LRO, except that we support the merging of ECN packets. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-25net: Use a percpu_counter for sockets_allocatedEric Dumazet
Instead of using one atomic_t per protocol, use a percpu_counter for "sockets_allocated", to reduce cache line contention on heavy duty network servers. Note : We revert commit (248969ae31e1b3276fc4399d67ce29a5d81e6fd9 net: af_unix can make unix_nr_socks visbile in /proc), since it is not anymore used after sock_prot_inuse_add() addition Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-23net: Convert TCP/DCCP listening hash tables to use RCUEric Dumazet
This is the last step to be able to perform full RCU lookups in __inet_lookup() : After established/timewait tables, we add RCU lookups to listening hash table. The only trick here is that a socket of a given type (TCP ipv4, TCP ipv6, ...) can now flight between two different tables (established and listening) during a RCU grace period, so we must use different 'nulls' end-of-chain values for two tables. We define a large value : #define LISTENING_NULLS_BASE (1U << 29) So that slots in listening table are guaranteed to have different end-of-chain values than slots in established table. A reader can still detect it finished its lookup in the right chain. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-20net: convert TCP/DCCP ehash rwlocks to spinlocksEric Dumazet
Now TCP & DCCP use RCU lookups, we can convert ehash rwlocks to spinlocks. /proc/net/tcp and other seq_file 'readers' can safely be converted to 'writers'. This should speedup writers, since spin_lock()/spin_unlock() only use one atomic operation instead of two for write_lock()/write_unlock() Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-20net: listening_hash get a spinlock per bucketEric Dumazet
This patch prepares RCU migration of listening_hash table for TCP/DCCP protocols. listening_hash table being small (32 slots per protocol), we add a spinlock for each slot, instead of a single rwlock for whole table. This should reduce hold time of readers, and writers concurrency. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-19include/net net/ - csum_partial - remove unnecessary castsJoe Perches
The first argument to csum_partial is const void * casts to char/u8 * are not necessary Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-16net: Convert TCP & DCCP hash tables to use RCU / hlist_nullsEric Dumazet
RCU was added to UDP lookups, using a fast infrastructure : - sockets kmem_cache use SLAB_DESTROY_BY_RCU and dont pay the price of call_rcu() at freeing time. - hlist_nulls permits to use few memory barriers. This patch uses same infrastructure for TCP/DCCP established and timewait sockets. Thanks to SLAB_DESTROY_BY_RCU, no slowdown for applications using short lived TCP connections. A followup patch, converting rwlocks to spinlocks will even speedup this case. __inet_lookup_established() is pretty fast now we dont have to dirty a contended cache line (read_lock/read_unlock) Only established and timewait hashtable are converted to RCU (bind table and listen table are still using traditional locking) Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-03net: clean up net/ipv4/tcp_ipv4.cJianjun Kong
Signed-off-by: Jianjun Kong <jianjun@zeuux.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-31net: replace NIPQUAD() in net/ipv4/ net/ipv6/Harvey Harrison
Using NIPQUAD() with NIPQUAD_FMT, %d.%d.%d.%d or %u.%u.%u.%u can be replaced with %pI4 Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-09tcpv[46]: fix md5 pseudoheader address field orderingIlpo Järvinen
Maybe it's just me but I guess those md5 people made a mess out of it by having *_md5_hash_* to use daddr, saddr order instead of the one that is natural (and equal to what csum functions use). For the segment were sending, the original addresses are reversed so buff's saddr == skb's daddr and vice-versa. Maybe I can finally proceed with unification of some code after fixing it first... :-) Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-08tcp: fix length used for checksum in a resetIlpo Järvinen
While looking for some common code I came across difference in checksum calculation between tcp_v6_send_(reset|ack) I couldn't explain. I checked both v4 and v6 and found out that both seem to have the same "feature". I couldn't find anything in rfc nor anywhere else which would state that md5 option should be ignored like it was in case of reset so I came to a conclusion that this is probably a genuine bug. I suspect that addition of md5 just was fooled by the excessive copy-paste code in those functions and the reset part was never tested well enough to find out the problem. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-07inet_hashtables: Add inet_lookup_skb helpersArnaldo Carvalho de Melo
To be able to use the cached socket reference in the skb during input processing we add a new set of lookup functions that receive the skb on their argument list. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: KOVACS Krisztian <hidden@sch.bme.hu> Signed-off-by: David S. Miller <davem@davemloft.net>