- 06 5月, 2017 1 次提交
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由 Eric Dumazet 提交于
Whole point of randomization was to hide server uptime, but an attacker can simply start a syn flood and TCP generates 'old style' timestamps, directly revealing server jiffies value. Also, TSval sent by the server to a particular remote address vary depending on syncookies being sent or not, potentially triggering PAWS drops for innocent clients. Lets implement proper randomization, including for SYNcookies. Also we do not need to export sysctl_tcp_timestamps, since it is not used from a module. In v2, I added Florian feedback and contribution, adding tsoff to tcp_get_cookie_sock(). v3 removed one unused variable in tcp_v4_connect() as Florian spotted. Fixes: 95a22cae ("tcp: randomize tcp timestamp offsets for each connection") Signed-off-by: NEric Dumazet <edumazet@google.com> Reviewed-by: NFlorian Westphal <fw@strlen.de> Tested-by: NFlorian Westphal <fw@strlen.de> Cc: Yuchung Cheng <ycheng@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 10 1月, 2017 1 次提交
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由 Jason A. Donenfeld 提交于
SHA1 is slower and less secure than SipHash, and so replacing syncookie generation with SipHash makes natural sense. Some BSDs have been doing this for several years in fact. The speedup should be similar -- and even more impressive -- to the speedup from the sequence number fix in this series. Signed-off-by: NJason A. Donenfeld <Jason@zx2c4.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: David Miller <davem@davemloft.net> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 03 12月, 2016 1 次提交
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由 Florian Westphal 提交于
jiffies based timestamps allow for easy inference of number of devices behind NAT translators and also makes tracking of hosts simpler. commit ceaa1fef ("tcp: adding a per-socket timestamp offset") added the main infrastructure that is needed for per-connection ts randomization, in particular writing/reading the on-wire tcp header format takes the offset into account so rest of stack can use normal tcp_time_stamp (jiffies). So only two items are left: - add a tsoffset for request sockets - extend the tcp isn generator to also return another 32bit number in addition to the ISN. Re-use of ISN generator also means timestamps are still monotonically increasing for same connection quadruple, i.e. PAWS will still work. Includes fixes from Eric Dumazet. Signed-off-by: NFlorian Westphal <fw@strlen.de> Acked-by: NEric Dumazet <edumazet@google.com> Acked-by: NYuchung Cheng <ycheng@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 05 11月, 2016 1 次提交
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由 Lorenzo Colitti 提交于
- Use the UID in routing lookups made by protocol connect() and sendmsg() functions. - Make sure that routing lookups triggered by incoming packets (e.g., Path MTU discovery) take the UID of the socket into account. - For packets not associated with a userspace socket, (e.g., ping replies) use UID 0 inside the user namespace corresponding to the network namespace the socket belongs to. This allows all namespaces to apply routing and iptables rules to kernel-originated traffic in that namespaces by matching UID 0. This is better than using the UID of the kernel socket that is sending the traffic, because the UID of kernel sockets created at namespace creation time (e.g., the per-processor ICMP and TCP sockets) is the UID of the user that created the socket, which might not be mapped in the namespace. Tested: compiles allnoconfig, allyesconfig, allmodconfig Tested: https://android-review.googlesource.com/253302Signed-off-by: NLorenzo Colitti <lorenzo@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 28 4月, 2016 1 次提交
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由 Eric Dumazet 提交于
Rename NET_INC_STATS_BH() to __NET_INC_STATS() and NET_ADD_STATS_BH() to __NET_ADD_STATS() Signed-off-by: NEric Dumazet <edumazet@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 16 3月, 2016 1 次提交
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由 Peter Zijlstra 提交于
$ make tags GEN tags ctags: Warning: drivers/acpi/processor_idle.c:64: null expansion of name pattern "\1" ctags: Warning: drivers/xen/events/events_2l.c:41: null expansion of name pattern "\1" ctags: Warning: kernel/locking/lockdep.c:151: null expansion of name pattern "\1" ctags: Warning: kernel/rcu/rcutorture.c:133: null expansion of name pattern "\1" ctags: Warning: kernel/rcu/rcutorture.c:135: null expansion of name pattern "\1" ctags: Warning: kernel/workqueue.c:323: null expansion of name pattern "\1" ctags: Warning: net/ipv4/syncookies.c:53: null expansion of name pattern "\1" ctags: Warning: net/ipv6/syncookies.c:44: null expansion of name pattern "\1" ctags: Warning: net/rds/page.c:45: null expansion of name pattern "\1" Which are all the result of the DEFINE_PER_CPU pattern: scripts/tags.sh:200: '/\<DEFINE_PER_CPU([^,]*, *\([[:alnum:]_]*\)/\1/v/' scripts/tags.sh:201: '/\<DEFINE_PER_CPU_SHARED_ALIGNED([^,]*, *\([[:alnum:]_]*\)/\1/v/' The below cures them. All except the workqueue one are within reasonable distance of the 80 char limit. TJ do you have any preference on how to fix the wq one, or shall we just not care its too long? Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org> Acked-by: NDavid S. Miller <davem@davemloft.net> Acked-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Tejun Heo <tj@kernel.org> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 08 2月, 2016 1 次提交
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由 Nikolay Borisov 提交于
Signed-off-by: NNikolay Borisov <kernel@kyup.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 19 12月, 2015 1 次提交
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由 David Ahern 提交于
Allow accepted sockets to derive their sk_bound_dev_if setting from the l3mdev domain in which the packets originated. A sysctl setting is added to control the behavior which is similar to sk_mark and sysctl_tcp_fwmark_accept. This effectively allow a process to have a "VRF-global" listen socket, with child sockets bound to the VRF device in which the packet originated. A similar behavior can be achieved using sk_mark, but a solution using marks is incomplete as it does not handle duplicate addresses in different L3 domains/VRFs. Allowing sockets to inherit the sk_bound_dev_if from l3mdev domain provides a complete solution. Signed-off-by: NDavid Ahern <dsa@cumulusnetworks.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 03 12月, 2015 1 次提交
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由 Eric Dumazet 提交于
This patch addresses multiple problems : UDP/RAW sendmsg() need to get a stable struct ipv6_txoptions while socket is not locked : Other threads can change np->opt concurrently. Dmitry posted a syzkaller (http://github.com/google/syzkaller) program desmonstrating use-after-free. Starting with TCP/DCCP lockless listeners, tcp_v6_syn_recv_sock() and dccp_v6_request_recv_sock() also need to use RCU protection to dereference np->opt once (before calling ipv6_dup_options()) This patch adds full RCU protection to np->opt Reported-by: NDmitry Vyukov <dvyukov@google.com> Signed-off-by: NEric Dumazet <edumazet@google.com> Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 13 10月, 2015 1 次提交
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由 Eric Dumazet 提交于
One 32bit hole is following skc_refcnt, use it. skc_incoming_cpu can also be an union for request_sock rcv_wnd. Signed-off-by: NEric Dumazet <edumazet@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 05 10月, 2015 1 次提交
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由 Eric Dumazet 提交于
inet_reqsk_alloc() is used to allocate a temporary request in order to generate a SYNACK with a cookie. Then later, syncookie validation also uses a temporary request. These paths already took a reference on listener refcount, we can avoid a couple of atomic operations. Signed-off-by: NEric Dumazet <edumazet@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 30 9月, 2015 1 次提交
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由 Eric Dumazet 提交于
Some common IPv4/IPv6 code can be factorized. Also constify cookie_init_sequence() socket argument. Signed-off-by: NEric Dumazet <edumazet@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 22 9月, 2015 1 次提交
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由 Yuchung Cheng 提交于
Currently SYN/ACK RTT is measured in jiffies. For LAN the SYN/ACK RTT is often measured as 0ms or sometimes 1ms, which would affect RTT estimation and min RTT samping used by some congestion control. This patch improves SYN/ACK RTT to be usec resolution if platform supports it. While the timestamping of SYN/ACK is done in request sock, the RTT measurement is carefully arranged to avoid storing another u64 timestamp in tcp_sock. For regular handshake w/o SYNACK retransmission, the RTT is sampled right after the child socket is created and right before the request sock is released (tcp_check_req() in tcp_minisocks.c) For Fast Open the child socket is already created when SYN/ACK was sent, the RTT is sampled in tcp_rcv_state_process() after processing the final ACK an right before the request socket is released. If the SYN/ACK was retransmistted or SYN-cookie was used, we rely on TCP timestamps to measure the RTT. The sample is taken at the same place in tcp_rcv_state_process() after the timestamp values are validated in tcp_validate_incoming(). Note that we do not store TS echo value in request_sock for SYN-cookies, because the value is already stored in tp->rx_opt used by tcp_ack_update_rtt(). One side benefit is that the RTT measurement now happens before initializing congestion control (of the passive side). Therefore the congestion control can use the SYN/ACK RTT. Signed-off-by: NYuchung Cheng <ycheng@google.com> Signed-off-by: NNeal Cardwell <ncardwell@google.com> Signed-off-by: NEric Dumazet <edumazet@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 08 6月, 2015 1 次提交
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由 Eric Dumazet 提交于
IPv4 and IPv6 share same implementation of get_cookie_sock(), and there is no point inlining it. We add tcp_ prefix to the common helper name and export it. Signed-off-by: NEric Dumazet <edumazet@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 25 3月, 2015 1 次提交
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由 Eric Dumazet 提交于
ss should display ipv4 mapped request sockets like this : tcp SYN-RECV 0 0 ::ffff:192.168.0.1:8080 ::ffff:192.0.2.1:35261 and not like this : tcp SYN-RECV 0 0 192.168.0.1:8080 192.0.2.1:35261 We should init ireq->ireq_family based on listener sk_family, not the actual protocol carried by SYN packet. This means we can set ireq_family in inet_reqsk_alloc() Fixes: 3f66b083 ("inet: introduce ireq_family") Signed-off-by: NEric Dumazet <edumazet@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 21 3月, 2015 1 次提交
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由 Eric Dumazet 提交于
One of the major issue for TCP is the SYNACK rtx handling, done by inet_csk_reqsk_queue_prune(), fired by the keepalive timer of a TCP_LISTEN socket. This function runs for awful long times, with socket lock held, meaning that other cpus needing this lock have to spin for hundred of ms. SYNACK are sent in huge bursts, likely to cause severe drops anyway. This model was OK 15 years ago when memory was very tight. We now can afford to have a timer per request sock. Timer invocations no longer need to lock the listener, and can be run from all cpus in parallel. With following patch increasing somaxconn width to 32 bits, I tested a listener with more than 4 million active request sockets, and a steady SYNFLOOD of ~200,000 SYN per second. Host was sending ~830,000 SYNACK per second. This is ~100 times more what we could achieve before this patch. Later, we will get rid of the listener hash and use ehash instead. Signed-off-by: NEric Dumazet <edumazet@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 18 3月, 2015 3 次提交
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由 Eric Dumazet 提交于
While testing last patch series, I found req sock refcounting was wrong. We must set skc_refcnt to 1 for all request socks added in hashes, but also on request sockets created by FastOpen or syncookies. It is tricky because we need to defer this initialization so that future RCU lookups do not try to take a refcount on a not yet fully initialized request socket. Also get rid of ireq_refcnt alias. Signed-off-by: NEric Dumazet <edumazet@google.com> Fixes: 13854e5a ("inet: add proper refcounting to request sock") Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Eric Dumazet 提交于
The listener field in struct tcp_request_sock is a pointer back to the listener. We now have req->rsk_listener, so TCP only needs one boolean and not a full pointer. Signed-off-by: NEric Dumazet <edumazet@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Eric Dumazet 提交于
listener socket can be used to set net pointer, and will be later used to hold a reference on listener. Add a const qualifier to first argument (struct request_sock_ops *), and factorize all write_pnet(&ireq->ireq_net, sock_net(sk)); Signed-off-by: NEric Dumazet <edumazet@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 13 3月, 2015 2 次提交
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由 Eric Dumazet 提交于
Before inserting request socks into general hash table, fill their socket family. Signed-off-by: NEric Dumazet <edumazet@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Eric Dumazet 提交于
I forgot to update dccp_v6_conn_request() & cookie_v6_check(). They both need to set ireq->ireq_net and ireq->ir_cookie Lets clear ireq->ir_cookie in inet_reqsk_alloc() Signed-off-by: NEric Dumazet <edumazet@google.com> Fixes: 33cf7c90 ("net: add real socket cookies") Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 05 11月, 2014 2 次提交
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由 Florian Westphal 提交于
This patch allows to set ECN on a per-route basis in case the sysctl tcp_ecn is not set to 1. In other words, when ECN is set for specific routes, it provides a tcp_ecn=1 behaviour for that route while the rest of the stack acts according to the global settings. One can use 'ip route change dev $dev $net features ecn' to toggle this. Having a more fine-grained per-route setting can be beneficial for various reasons, for example, 1) within data centers, or 2) local ISPs may deploy ECN support for their own video/streaming services [1], etc. There was a recent measurement study/paper [2] which scanned the Alexa's publicly available top million websites list from a vantage point in US, Europe and Asia: Half of the Alexa list will now happily use ECN (tcp_ecn=2, most likely blamed to commit 255cac91 ("tcp: extend ECN sysctl to allow server-side only ECN") ;)); the break in connectivity on-path was found is about 1 in 10,000 cases. Timeouts rather than receiving back RSTs were much more common in the negotiation phase (and mostly seen in the Alexa middle band, ranks around 50k-150k): from 12-thousand hosts on which there _may_ be ECN-linked connection failures, only 79 failed with RST when _not_ failing with RST when ECN is not requested. It's unclear though, how much equipment in the wild actually marks CE when buffers start to fill up. We thought about a fallback to non-ECN for retransmitted SYNs as another global option (which could perhaps one day be made default), but as Eric points out, there's much more work needed to detect broken middleboxes. Two examples Eric mentioned are buggy firewalls that accept only a single SYN per flow, and middleboxes that successfully let an ECN flow establish, but later mark CE for all packets (so cwnd converges to 1). [1] http://www.ietf.org/proceedings/89/slides/slides-89-tsvarea-1.pdf, p.15 [2] http://ecn.ethz.ch/ Joint work with Daniel Borkmann. Reference: http://thread.gmane.org/gmane.linux.network/335797Suggested-by: NHannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: NEric Dumazet <edumazet@google.com> Signed-off-by: NDaniel Borkmann <dborkman@redhat.com> Signed-off-by: NFlorian Westphal <fw@strlen.de> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Florian Westphal 提交于
The function cookie_check_timestamp(), both called from IPv4/6 context, is being used to decode the echoed timestamp from the SYN/ACK into TCP options used for follow-up communication with the peer. We can remove ECN handling from that function, split it into a separate one, and simply rename the original function into cookie_decode_options(). cookie_decode_options() just fills in tcp_option struct based on the echoed timestamp received from the peer. Anything that fails in this function will actually discard the request socket. While this is the natural place for decoding options such as ECN which commit 172d69e6 ("syncookies: add support for ECN") added, we argue that in particular for ECN handling, it can be checked at a later point in time as the request sock would actually not need to be dropped from this, but just ECN support turned off. Therefore, we split this functionality into cookie_ecn_ok(), which tells us if the timestamp indicates ECN support AND the tcp_ecn sysctl is enabled. This prepares for per-route ECN support: just looking at the tcp_ecn sysctl won't be enough anymore at that point; if the timestamp indicates ECN and sysctl tcp_ecn == 0, we will also need to check the ECN dst metric. This would mean adding a route lookup to cookie_check_timestamp(), which we definitely want to avoid. As we already do a route lookup at a later point in cookie_{v4,v6}_check(), we can simply make use of that as well for the new cookie_ecn_ok() function w/o any additional cost. Joint work with Daniel Borkmann. Acked-by: NEric Dumazet <edumazet@google.com> Signed-off-by: NDaniel Borkmann <dborkman@redhat.com> Signed-off-by: NFlorian Westphal <fw@strlen.de> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 31 10月, 2014 1 次提交
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由 Florian Westphal 提交于
Only count packets that failed cookie-authentication. We can get SYNCOOKIESFAILED > 0 while we never even sent a single cookie. Signed-off-by: NFlorian Westphal <fw@strlen.de> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 24 10月, 2014 1 次提交
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由 Kenjiro Nakayama 提交于
Remove trailing whitespace in tcp.h icmp.c syncookies.c Signed-off-by: NKenjiro Nakayama <nakayamakenjiro@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 18 10月, 2014 1 次提交
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由 Eric Dumazet 提交于
Commit 971f10ec ("tcp: better TCP_SKB_CB layout to reduce cache line misses") added a regression for SO_BINDTODEVICE on IPv6. This is because we still use inet6_iif() which expects that IP6 control block is still at the beginning of skb->cb[] This patch adds tcp_v6_iif() helper and uses it where necessary. Because __inet6_lookup_skb() is used by TCP and DCCP, we add an iif parameter to it. Signed-off-by: NEric Dumazet <edumazet@google.com> Fixes: 971f10ec ("tcp: better TCP_SKB_CB layout to reduce cache line misses") Acked-by: NCong Wang <cwang@twopensource.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 29 9月, 2014 1 次提交
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由 Eric Dumazet 提交于
ipv6_opt_accepted() assumes IP6CB(skb) holds the struct inet6_skb_parm that it needs. Lets not assume this, as TCP stack might use a different place. Signed-off-by: NEric Dumazet <edumazet@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 28 8月, 2014 1 次提交
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由 Florian Westphal 提交于
only written once. Signed-off-by: NFlorian Westphal <fw@strlen.de> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 27 8月, 2014 1 次提交
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由 Christoph Lameter 提交于
Replace uses of get_cpu_var for address calculation through this_cpu_ptr. Cc: netdev@vger.kernel.org Cc: Eric Dumazet <edumazet@google.com> Acked-by: NDavid S. Miller <davem@davemloft.net> Signed-off-by: NChristoph Lameter <cl@linux.com> Signed-off-by: NTejun Heo <tj@kernel.org>
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- 28 6月, 2014 1 次提交
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由 Octavian Purdila 提交于
Since pktops is only used for IPv6 only and opts is used for IPv4 only, we can move these fields into a union and this allows us to drop the inet6_reqsk_alloc function as after this change it becomes equivalent with inet_reqsk_alloc. This patch also fixes a kmemcheck issue in the IPv6 stack: the flags field was not annotated after a request_sock was allocated. Signed-off-by: NOctavian Purdila <octavian.purdila@intel.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 14 5月, 2014 1 次提交
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由 Lorenzo Colitti 提交于
When using mark-based routing, sockets returned from accept() may need to be marked differently depending on the incoming connection request. This is the case, for example, if different socket marks identify different networks: a listening socket may want to accept connections from all networks, but each connection should be marked with the network that the request came in on, so that subsequent packets are sent on the correct network. This patch adds a sysctl to mark TCP sockets based on the fwmark of the incoming SYN packet. If enabled, and an unmarked socket receives a SYN, then the SYN packet's fwmark is written to the connection's inet_request_sock, and later written back to the accepted socket when the connection is established. If the socket already has a nonzero mark, then the behaviour is the same as it is today, i.e., the listening socket's fwmark is used. Black-box tested using user-mode linux: - IPv4/IPv6 SYN+ACK, FIN, etc. packets are routed based on the mark of the incoming SYN packet. - The socket returned by accept() is marked with the mark of the incoming SYN packet. - Tested with syncookies=1 and syncookies=2. Signed-off-by: NLorenzo Colitti <lorenzo@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 06 12月, 2013 1 次提交
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由 Steffen Klassert 提交于
FLOWI_FLAG_CAN_SLEEP was used to notify xfrm about the posibility to sleep until the needed states are resolved. This code is gone, so FLOWI_FLAG_CAN_SLEEP is not needed anymore. Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>
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- 20 10月, 2013 1 次提交
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由 Hannes Frederic Sowa 提交于
This patch splits the secret key for syncookies for ipv4 and ipv6 and initializes them with net_get_random_once. This change was the reason I did this series. I think the initialization of the syncookie_secret is way to early. Cc: Florian Westphal <fw@strlen.de> Cc: Eric Dumazet <edumazet@google.com> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 11 10月, 2013 1 次提交
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由 Eric Dumazet 提交于
In commit 634fb979 ("inet: includes a sock_common in request_sock") I forgot that the two ports in sock_common do not have same byte order : skc_dport is __be16 (network order), but skc_num is __u16 (host order) So sparse complains because ir_loc_port (mapped into skc_num) is considered as __u16 while it should be __be16 Let rename ir_loc_port to ireq->ir_num (analogy with inet->inet_num), and perform appropriate htons/ntohs conversions. Signed-off-by: NEric Dumazet <edumazet@google.com> Reported-by: NWu Fengguang <fengguang.wu@intel.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 10 10月, 2013 1 次提交
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由 Eric Dumazet 提交于
TCP listener refactoring, part 5 : We want to be able to insert request sockets (SYN_RECV) into main ehash table instead of the per listener hash table to allow RCU lookups and remove listener lock contention. This patch includes the needed struct sock_common in front of struct request_sock This means there is no more inet6_request_sock IPv6 specific structure. Following inet_request_sock fields were renamed as they became macros to reference fields from struct sock_common. Prefix ir_ was chosen to avoid name collisions. loc_port -> ir_loc_port loc_addr -> ir_loc_addr rmt_addr -> ir_rmt_addr rmt_port -> ir_rmt_port iif -> ir_iif Signed-off-by: NEric Dumazet <edumazet@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 24 9月, 2013 2 次提交
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由 Florian Westphal 提交于
Halve mss table size to make blind cookie guessing more difficult. This is sad since the tables were already small, but there is little alternative except perhaps adding more precise mss information in the tcp timestamp. Timestamps are unfortunately not ubiquitous. Guessing all possible cookie values still has 8-in 2**32 chance. Reported-by: NJakob Lell <jakob@jakoblell.com> Signed-off-by: NFlorian Westphal <fw@strlen.de> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Florian Westphal 提交于
We currently accept cookies that were created less than 4 minutes ago (ie, cookies with counter delta 0-3). Combined with the 8 mss table values, this yields 32 possible values (out of 2**32) that will be valid. Reducing the lifetime to < 2 minutes halves the guessing chance while still providing a large enough period. While at it, get rid of jiffies value -- they overflow too quickly on 32 bit platforms. getnstimeofday is used to create a counter that increments every 64s. perf shows getnstimeofday cost is negible compared to sha_transform; normal tcp initial sequence number generation uses getnstimeofday, too. Reported-by: NJakob Lell <jakob@jakoblell.com> Signed-off-by: NFlorian Westphal <fw@strlen.de> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 28 8月, 2013 1 次提交
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由 Patrick McHardy 提交于
Extract the local TCP stack independant parts of tcp_v6_init_sequence() and cookie_v6_check() and export them for use by the upcoming IPv6 SYNPROXY target. Signed-off-by: NPatrick McHardy <kaber@trash.net> Acked-by: NDavid S. Miller <davem@davemloft.net> Tested-by: NMartin Topholm <mph@one.com> Signed-off-by: NJesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>
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- 18 3月, 2013 1 次提交
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由 Christoph Paasch 提交于
TCPCT uses option-number 253, reserved for experimental use and should not be used in production environments. Further, TCPCT does not fully implement RFC 6013. As a nice side-effect, removing TCPCT increases TCP's performance for very short flows: Doing an apache-benchmark with -c 100 -n 100000, sending HTTP-requests for files of 1KB size. before this patch: average (among 7 runs) of 20845.5 Requests/Second after: average (among 7 runs) of 21403.6 Requests/Second Signed-off-by: NChristoph Paasch <christoph.paasch@uclouvain.be> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 07 1月, 2013 1 次提交
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由 Hannes Frederic Sowa 提交于
As per suggestion from Eric Dumazet this patch makes tcp_ecn sysctl namespace aware. The reason behind this patch is to ease the testing of ecn problems on the internet and allows applications to tune their own use of ecn. Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: David Miller <davem@davemloft.net> Cc: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: NEric Dumazet <edumazet@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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