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2014-05-12net: rename local_df to ignore_dfWANG Cong
As suggested by several people, rename local_df to ignore_df, since it means "ignore df bit if it is set". Cc: Maciej Żenczykowski <maze@google.com> Cc: Florian Westphal <fw@strlen.de> Cc: David S. Miller <davem@davemloft.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Acked-by: Maciej Żenczykowski <maze@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-07net: ip: push gso skb forwarding handling down the stackFlorian Westphal
Doing the segmentation in the forward path has one major drawback: When using virtio, we may process gso udp packets coming from host network stack. In that case, netfilter POSTROUTING will see one packet with udp header followed by multiple ip fragments. Delay the segmentation and do it after POSTROUTING invocation to avoid this. Fixes: fe6cc55f3a9 ("net: ip, ipv6: handle gso skbs in forwarding path") Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-07net: ipv4: ip_forward: fix inverted local_df testFlorian Westphal
local_df means 'ignore DF bit if set', so if its set we're allowed to perform ip fragmentation. This wasn't noticed earlier because the output path also drops such skbs (and emits needed icmp error) and because netfilter ip defrag did not set local_df until couple of days ago. Only difference is that DF-packets-larger-than MTU now discarded earlier (f.e. we avoid pointless netfilter postrouting trip). While at it, drop the repeated test ip_exceeds_mtu, checking it once is enough... Fixes: fe6cc55f3a9 ("net: ip, ipv6: handle gso skbs in forwarding path") Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-19Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Conflicts: drivers/net/bonding/bond_3ad.h drivers/net/bonding/bond_main.c Two minor conflicts in bonding, both of which were overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-13ipv4: ip_forward: perform skb->pkt_type check at the beginningDenis Kirjanov
Packets which have L2 address different from ours should be already filtered before entering into ip_forward(). Perform that check at the beginning to avoid processing such packets. Signed-off-by: Denis Kirjanov <kda@linux-powerpc.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-13net: ip, ipv6: handle gso skbs in forwarding pathFlorian Westphal
Marcelo Ricardo Leitner reported problems when the forwarding link path has a lower mtu than the incoming one if the inbound interface supports GRO. Given: Host <mtu1500> R1 <mtu1200> R2 Host sends tcp stream which is routed via R1 and R2. R1 performs GRO. In this case, the kernel will fail to send ICMP fragmentation needed messages (or pkt too big for ipv6), as GSO packets currently bypass dstmtu checks in forward path. Instead, Linux tries to send out packets exceeding the mtu. When locking route MTU on Host (i.e., no ipv4 DF bit set), R1 does not fragment the packets when forwarding, and again tries to send out packets exceeding R1-R2 link mtu. This alters the forwarding dstmtu checks to take the individual gso segment lengths into account. For ipv6, we send out pkt too big error for gso if the individual segments are too big. For ipv4, we either send icmp fragmentation needed, or, if the DF bit is not set, perform software segmentation and let the output path create fragments when the packet is leaving the machine. It is not 100% correct as the error message will contain the headers of the GRO skb instead of the original/segmented one, but it seems to work fine in my (limited) tests. Eric Dumazet suggested to simply shrink mss via ->gso_size to avoid sofware segmentation. However it turns out that skb_segment() assumes skb nr_frags is related to mss size so we would BUG there. I don't want to mess with it considering Herbert and Eric disagree on what the correct behavior should be. Hannes Frederic Sowa notes that when we would shrink gso_size skb_segment would then also need to deal with the case where SKB_MAX_FRAGS would be exceeded. This uses sofware segmentation in the forward path when we hit ipv4 non-DF packets and the outgoing link mtu is too small. Its not perfect, but given the lack of bug reports wrt. GRO fwd being broken this is a rare case anyway. Also its not like this could not be improved later once the dust settles. Acked-by: Herbert Xu <herbert@gondor.apana.org.au> Reported-by: Marcelo Ricardo Leitner <mleitner@redhat.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-13ipv4: introduce ip_dst_mtu_maybe_forward and protect forwarding path against ↵Hannes Frederic Sowa
pmtu spoofing While forwarding we should not use the protocol path mtu to calculate the mtu for a forwarded packet but instead use the interface mtu. We mark forwarded skbs in ip_forward with IPSKB_FORWARDED, which was introduced for multicast forwarding. But as it does not conflict with our usage in unicast code path it is perfect for reuse. I moved the functions ip_sk_accept_pmtu, ip_sk_use_pmtu and ip_skb_dst_mtu along with the new ip_dst_mtu_maybe_forward to net/ip.h to fix circular dependencies because of IPSKB_FORWARDED. Because someone might have written a software which does probe destinations manually and expects the kernel to honour those path mtus I introduced a new per-namespace "ip_forward_use_pmtu" knob so someone can disable this new behaviour. We also still use mtus which are locked on a route for forwarding. The reason for this change is, that path mtus information can be injected into the kernel via e.g. icmp_err protocol handler without verification of local sockets. As such, this could cause the IPv4 forwarding path to wrongfully emit fragmentation needed notifications or start to fragment packets along a path. Tunnel and ipsec output paths clear IPCB again, thus IPSKB_FORWARDED won't be set and further fragmentation logic will use the path mtu to determine the fragmentation size. They also recheck packet size with help of path mtu discovery and report appropriate errors. Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: David Miller <davem@davemloft.net> Cc: John Heffner <johnwheffner@gmail.com> Cc: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-10-08ipv4: introduce rt_uses_gatewayJulian Anastasov
Add new flag to remember when route is via gateway. We will use it to allow rt_gateway to contain address of directly connected host for the cases when DST_NOCACHE is used or when the NH exception caches per-destination route without DST_NOCACHE flag, i.e. when routes are not used for other destinations. By this way we force the neighbour resolving to work with the routed destination but we can use different address in the packet, feature needed for IPVS-DR where original packet for virtual IP is routed via route to real IP. Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-10-08ipv4: fix forwarding for strict source routesJulian Anastasov
After the change "Adjust semantics of rt->rt_gateway" (commit f8126f1d51) rt_gateway can be 0 but ip_forward() compares it directly with nexthop. What we want here is to check if traffic is to directly connected nexthop and to fail if using gateway. Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-06-07snmp: fix OutOctets counter to include forwarded datagramsVincent Bernat
RFC 4293 defines ipIfStatsOutOctets (similar definition for ipSystemStatsOutOctets): The total number of octets in IP datagrams delivered to the lower layers for transmission. Octets from datagrams counted in ipIfStatsOutTransmits MUST be counted here. And ipIfStatsOutTransmits: The total number of IP datagrams that this entity supplied to the lower layers for transmission. This includes datagrams generated locally and those forwarded by this entity. Therefore, IPSTATS_MIB_OUTOCTETS must be incremented when incrementing IPSTATS_MIB_OUTFORWDATAGRAMS. IP_UPD_PO_STATS is not used since ipIfStatsOutRequests must not include forwarded datagrams: The total number of IP datagrams that local IP user-protocols (including ICMP) supplied to IP in requests for transmission. Note that this counter does not include any datagrams counted in ipIfStatsOutForwDatagrams. Signed-off-by: Vincent Bernat <bernat@luffy.cx> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-15ipv4: fix checkpatch errorsDaniel Baluta
Fix checkpatch errors of the following type: * ERROR: "foo * bar" should be "foo *bar" * ERROR: "(foo*)" should be "(foo *)" Signed-off-by: Daniel Baluta <dbaluta@ixiacom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-23ipv4: Save nexthop address of LSRR/SSRR option to IPCB.Li Wei
We can not update iph->daddr in ip_options_rcv_srr(), It is too early. When some exception ocurred later (eg. in ip_forward() when goto sr_failed) we need the ip header be identical to the original one as ICMP need it. Add a field 'nexthop' in struct ip_options to save nexthop of LSRR or SSRR option. Signed-off-by: Li Wei <lw@cn.fujitsu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-12ipv4: Fix 'iph' use before set.David S. Miller
I swear none of my compilers warned about this, yet it is so obvious. > net/ipv4/ip_forward.c: In function 'ip_forward': > net/ipv4/ip_forward.c:87: warning: 'iph' may be used uninitialized in this function Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-12ipv4: Elide use of rt->rt_dst in ip_forward()David S. Miller
No matter what kind of header mangling occurs due to IP options processing, rt->rt_dst will always equal iph->daddr in the packet. So we can safely use iph->daddr instead of rt->rt_dst here. Signed-off-by: David S. Miller <davem@davemloft.net>
2010-06-10net-next: remove useless union keywordChangli Gao
remove useless union keyword in rtable, rt6_info and dn_route. Since there is only one member in a union, the union keyword isn't useful. Signed-off-by: Changli Gao <xiaosuo@gmail.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-04-20Merge branch 'master' of /repos/git/net-next-2.6Patrick McHardy
Conflicts: Documentation/feature-removal-schedule.txt net/ipv6/netfilter/ip6t_REJECT.c net/netfilter/xt_limit.c Signed-off-by: Patrick McHardy <kaber@trash.net>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo
implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-25netfilter: ipv4: use NFPROTO values for NF_HOOK invocationJan Engelhardt
The semantic patch that was used: // <smpl> @@ @@ (NF_HOOK |NF_HOOK_COND |nf_hook )( -PF_INET, +NFPROTO_IPV4, ...) // </smpl> Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
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>
2008-10-28net: reduce structures when XFRM=nAlexey Dobriyan
ifdef out * struct sk_buff::sp (pointer) * struct dst_entry::xfrm (pointer) * struct sock::sk_policy (2 pointers) Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-16mib: add net to IP_INC_STATS_BHPavel Emelyanov
Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-16mib: add net to IP_INC_STATSPavel Emelyanov
All the callers already have either the net itself, or the place where to get it from. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-06-19net: Discard and warn about LRO'd skbs received for forwardingBen Hutchings
Add skb_warn_if_lro() to test whether an skb was received with LRO and warn if so. Change br_forward(), ip_forward() and ip6_forward() to call it) and discard the skb if it returns true. Signed-off-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-06-11net: remove CVS keywordsAdrian Bunk
This patch removes CVS keywords that weren't updated for a long time from comments. Signed-off-by: Adrian Bunk <bunk@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-02Merge branch 'master' of ↵David S. Miller
git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: drivers/net/s2io.c
2008-03-28[NET]: Don't send ICMP_FRAG_NEEDED for GSO packetsRusty Russell
Commit 9af3912ec9e30509b76cb376abb65a4d8af27df3 ("[NET] Move DF check to ip_forward") added a new check to send ICMP fragmentation needed for large packets. Unlike the check in ip_finish_output(), it doesn't check for GSO. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-05[IPV4]: Add 'rtable' field in struct sk_buff to alias 'dst' and avoid castsEric Dumazet
(Anonymous) unions can help us to avoid ugly casts. A common cast it the (struct rtable *)skb->dst one. Defining an union like : union { struct dst_entry *dst; struct rtable *rtable; }; permits to use skb->rtable in place. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[NETFILTER]: Introduce NF_INET_ hook valuesPatrick McHardy
The IPv4 and IPv6 hook values are identical, yet some code tries to figure out the "correct" value by looking at the address family. Introduce NF_INET_* values for both IPv4 and IPv6. The old values are kept in a #ifndef __KERNEL__ section for userspace compatibility. Signed-off-by: Patrick McHardy <kaber@trash.net> Acked-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-15[IPV4]: Uninline netfilter okfnsPatrick McHardy
Now that we don't pass double skb pointers to nf_hook_slow anymore, gcc can generate tail calls for some of the netfilter hook okfn invocations, so there is no need to inline the functions anymore. This caused huge code bloat since we ended up with one inlined version and one out-of-line version since we pass the address to nf_hook_slow. Before: text data bss dec hex filename 8997385 1016524 524652 10538561 a0ce41 vmlinux After: text data bss dec hex filename 8994009 1016524 524652 10535185 a0c111 vmlinux ------------------------------------------------------- -3376 All cases have been verified to generate tail-calls with and without netfilter. The okfns in ipmr and xfrm4_input still remain inline because gcc can't generate tail-calls for them. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[IPV4] IPSEC: Omit redirect for tunnelled packet.Masahide NAKAMURA
IPv4 IPsec tunnel gateway incorrectly sends redirect to sender if it is onlink host when network device the IPsec tunnelled packet is arrived is the same as the one the decapsulated packet is sent. With this patch, it omits to send the redirect when the forwarding skbuff carries secpath, since such skbuff should be assumed as a decapsulated packet from IPsec tunnel by own. Request for comments: Alternatively we'd have another way to change net/ipv4/route.c (__mkroute_input) to use RTCF_DOREDIRECT flag unless skbuff has no secpath. It is better than this patch at performance point of view because IPv4 redirect judgement is done at routing slow-path. However, it should be taken care of resource changes between SAD(XFRM states) and routing table. In other words, When IPv4 SAD is changed does the related routing entry go to its slow-path? If not, it is reasonable to apply this patch. Signed-off-by: Masahide NAKAMURA <nakam@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-19[NET] IPV4: Fix whitespace errors.YOSHIFUJI Hideaki
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
2007-04-25[NET]: Allow forwarding of ip_summed except CHECKSUM_COMPLETEHerbert Xu
Right now Xen has a horrible hack that lets it forward packets with partial checksums. One of the reasons that CHECKSUM_PARTIAL and CHECKSUM_COMPLETE were added is so that we can get rid of this hack (where it creates two extra bits in the skbuff to essentially mirror ip_summed without being destroyed by the forwarding code). I had forgotten that I've already gone through all the deivce drivers last time around to make sure that they're looking at ip_summed == CHECKSUM_PARTIAL rather than ip_summed != 0 on transmit. In any case, I've now done that again so it should definitely be safe. Unfortunately nobody has yet added any code to update CHECKSUM_COMPLETE values on forward so we I'm setting that to CHECKSUM_NONE. This should be safe to remove for bridging but I'd like to check that code path first. So here is the patch that lets us get rid of the hack by preserving ip_summed (mostly) on forwarded packets. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[NET] Move DF check to ip_forwardJohn Heffner
Do fragmentation check in ip_forward, similar to ipv6 forwarding. Signed-off-by: John Heffner <jheffner@psc.edu> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[SK_BUFF]: Introduce ip_hdr(), remove skb->nh.iphArnaldo Carvalho de Melo
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-02-14[PATCH] remove many unneeded #includes of sched.hTim Schmielau
After Al Viro (finally) succeeded in removing the sched.h #include in module.h recently, it makes sense again to remove other superfluous sched.h includes. There are quite a lot of files which include it but don't actually need anything defined in there. Presumably these includes were once needed for macros that used to live in sched.h, but moved to other header files in the course of cleaning it up. To ease the pain, this time I did not fiddle with any header files and only removed #includes from .c-files, which tend to cause less trouble. Compile tested against 2.6.20-rc2 and 2.6.20-rc2-mm2 (with offsets) on alpha, arm, i386, ia64, mips, powerpc, and x86_64 with allnoconfig, defconfig, allmodconfig, and allyesconfig as well as a few randconfigs on x86_64 and all configs in arch/arm/configs on arm. I also checked that no new warnings were introduced by the patch (actually, some warnings are removed that were emitted by unnecessarily included header files). Signed-off-by: Tim Schmielau <tim@physik3.uni-rostock.de> Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-10[NET] IPV4: Fix whitespace errors.YOSHIFUJI Hideaki
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-30Remove obsolete #include <linux/config.h>Jörn Engel
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-06-12[IPV4]: Increment ipInHdrErrors when TTL expires.Weidong
Signed-off-by: Weidong <weid@nanjing-fnst.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[IPV4]: Remove some dead code from ip_forward()Thomas Graf
Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-04-16Linux-2.6.12-rc2Linus Torvalds
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!