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2013-08-19xfrm: choose protocol family by skb protocolHannes Frederic Sowa
We need to choose the protocol family by skb->protocol. Otherwise we call the wrong xfrm{4,6}_local_error handler in case an ipv6 sockets is used in ipv4 mode, in which case we should call down to xfrm4_local_error (ip6 sockets are a superset of ip4 ones). We are called before before ip_output functions, so skb->protocol is not reset. Cc: Steffen Klassert <steffen.klassert@secunet.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2013-08-14xfrm: make local error reporting more robustHannes Frederic Sowa
In xfrm4 and xfrm6 we need to take care about sockets of the other address family. This could happen because a 6in4 or 4in6 tunnel could get protected by ipsec. Because we don't want to have a run-time dependency on ipv6 when only using ipv4 xfrm we have to embed a pointer to the correct local_error function in xfrm_state_afinet and look it up when returning an error depending on the socket address family. Thanks to vi0ss for the great bug report: <https://bugzilla.kernel.org/show_bug.cgi?id=58691> v2: a) fix two more unsafe interpretations of skb->sk as ipv6 socket (xfrm6_local_dontfrag and __xfrm6_output) v3: a) add an EXPORT_SYMBOL_GPL(xfrm_local_error) to fix a link error when building ipv6 as a module (thanks to Steffen Klassert) Reported-by: <vi0oss@gmail.com> Cc: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2013-06-04xfrm: simplify the exit path of xfrm_output_one()Jean Sacren
Clean up unnecessary assignment and jump. While there, fix up the label name. Signed-off-by: Jean Sacren <sakiwit@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-05-23xfrm: properly handle invalid states as an errorTimo Teräs
The error exit path needs err explicitly set. Otherwise it returns success and the only caller, xfrm_output_resume(), would oops in skb_dst(skb)->ops derefence as skb_dst(skb) is NULL. Bug introduced in commit bb65a9cb (xfrm: removes a superfluous check and add a statistic). Signed-off-by: Timo Teräs <timo.teras@iki.fi> Cc: Li RongQing <roy.qing.li@gmail.com> Cc: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-02-01xfrm: fix a unbalanced lockLi RongQing
Signed-off-by: Li RongQing <roy.qing.li@gmail.com> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2013-01-07xfrm: removes a superfluous check and add a statisticLi RongQing
Remove the check if x->km.state equal to XFRM_STATE_VALID in xfrm_state_check_expire(), which will be done before call xfrm_state_check_expire(). add a LINUX_MIB_XFRMOUTSTATEINVALID statistic to record the outbound error due to invalid xfrm state. Signed-off-by: Li RongQing <roy.qing.li@gmail.com> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2012-03-22xfrm: Remove unused xfrm_state from xfrm_state_check_spaceSteffen Klassert
The xfrm_state argument is unused in this function, so remove it. Also the name xfrm_state_check_space does not really match what this function does. It actually checks if we have enough head and tailroom on the skb. So we rename the function to xfrm_skb_check_space. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-27dst: Clone child entry in skb_dst_popSteffen Klassert
We clone the child entry in skb_dst_pop before we call skb_dst_drop(). Otherwise we might kill the child right before we return it to the caller. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-27xfrm: Force a dst refcount before entering the xfrm type handlersSteffen Klassert
Crypto requests might return asynchronous. In this case we leave the rcu protected region, so force a refcount on the skb's destination entry before we enter the xfrm type input/output handlers. This fixes a crash when a route is deleted whilst sending IPsec data that is transformed by an asynchronous algorithm. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-13xfrm: Move IPsec replay detection functions to a separate fileSteffen Klassert
To support multiple versions of replay detection, we move the replay detection functions to a separate file and make them accessible via function pointers contained in the struct xfrm_replay. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Acked-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-13xfrm: Use separate low and high order bits of the sequence numbers in ↵Steffen Klassert
xfrm_skb_cb To support IPsec extended sequence numbers, we split the output sequence numbers of xfrm_skb_cb in low and high order 32 bits and we add the high order 32 bits to the input sequence numbers. All users are updated accordingly. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Acked-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-16xfrm: dont assume rcu_read_lock in xfrm_output_one()Eric Dumazet
ip_local_out() is called with rcu_read_lock() held from ip_queue_xmit() but not from other call sites. Reported-and-bisected-by: Nick Bowler <nbowler@elliptictech.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-06-04net: check for refcount if pop a stacked dst_entrySteffen Klassert
xfrm triggers a warning if dst_pop() drops a refcount on a noref dst. This patch changes dst_pop() to skb_dst_pop(). skb_dst_pop() drops the refcnt only on a refcounted dst. Also we don't clone the child dst_entry, so it is not refcounted and we can use skb_dst_set_noref() in xfrm_output_one(). Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.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>
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>
2008-11-25netns xfrm: per-netns MIBsAlexey Dobriyan
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-25netns xfrm: per-netns NETLINK_XFRM socketAlexey Dobriyan
Stub senders to init_net's one temporarily. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-09-30ipsec: Fix pskb_expand_head corruption in xfrm_state_check_spaceHerbert Xu
We're never supposed to shrink the headroom or tailroom. In fact, shrinking the headroom is a fatal action. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-08-13xfrm: remove unnecessary variable in xfrm_output_resume() 2nd tryJean-Christophe DUBOIS
Small fix removing an unnecessary intermediate variable. Signed-off-by: Jean-Christophe DUBOIS <jcd@tribudubois.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-05-12net: Allow netdevices to specify needed head/tailroomJohannes Berg
This patch adds needed_headroom/needed_tailroom members to struct net_device and updates many places that allocate sbks to use them. Not all of them can be converted though, and I'm sure I missed some (I mostly grepped for LL_RESERVED_SPACE) Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-29Remove duplicated unlikely() in IS_ERR()Hirofumi Nakagawa
Some drivers have duplicated unlikely() macros. IS_ERR() already has unlikely() in itself. This patch cleans up such pointless code. Signed-off-by: Hirofumi Nakagawa <hnakagawa@miraclelinux.com> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Jeff Garzik <jeff@garzik.org> Cc: Paul Clements <paul.clements@steeleye.com> Cc: Richard Purdie <rpurdie@rpsys.net> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: David Brownell <david-b@pacbell.net> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Cc: Michael Halcrow <mhalcrow@us.ibm.com> Cc: Anton Altaparmakov <aia21@cantab.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Carsten Otte <cotte@de.ibm.com> Cc: Patrick McHardy <kaber@trash.net> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Jaroslav Kysela <perex@perex.cz> Cc: Takashi Iwai <tiwai@suse.de> Acked-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-03-24[IPSEC]: Fix inter address family IPsec tunnel handling.Kazunori MIYAZAWA
Signed-off-by: Kazunori MIYAZAWA <kazunori@miyazawa.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-02-12[IPSEC]: Fix bogus usage of u64 on input sequence numberHerbert Xu
Al Viro spotted a bogus use of u64 on the input sequence number which is big-endian. This patch fixes it by giving the input sequence number its own member in the xfrm_skb_cb structure. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-31[XFRM]: Fix statistics.Masahide NAKAMURA
o Outbound sequence number overflow error status is counted as XfrmOutStateSeqError. o Additionaly, it changes inbound sequence number replay error name from XfrmInSeqOutOfWindow to XfrmInStateSeqError to apply name scheme above. o Inbound IPv4 UDP encapsuling type mismatch error is wrongly mapped to XfrmInStateInvalid then this patch fiex the error to XfrmInStateMismatch. Signed-off-by: Masahide NAKAMURA <nakam@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[IPSEC]: Return EOVERFLOW when output sequence number overflowsHerbert Xu
Previously we made it an error on the output path if the sequence number overflowed. However we did not set the err variable accordingly. This patch sets err to -EOVERFLOW in that case. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[IPSEC]: Fix double free on skb on async outputHerbert Xu
When the output transform returns EINPROGRESS due to async operation we'll free the skb the straight away as if it were an error. This patch fixes that so that the skb is freed when the async operation completes. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[XFRM]: Fix outbound statistics.Masahide NAKAMURA
Signed-off-by: Masahide NAKAMURA <nakam@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[XFRM]: Drop packets when replay counter would overflowPaul Moore
According to RFC4303, section 3.3.3 we need to drop outgoing packets which cause the replay counter to overflow: 3.3.3. Sequence Number Generation The sender's counter is initialized to 0 when an SA is established. The sender increments the sequence number (or ESN) counter for this SA and inserts the low-order 32 bits of the value into the Sequence Number field. Thus, the first packet sent using a given SA will contain a sequence number of 1. If anti-replay is enabled (the default), the sender checks to ensure that the counter has not cycled before inserting the new value in the Sequence Number field. In other words, the sender MUST NOT send a packet on an SA if doing so would cause the sequence number to cycle. An attempt to transmit a packet that would result in sequence number overflow is an auditable event. The audit log entry for this event SHOULD include the SPI value, current date/time, Source Address, Destination Address, and (in IPv6) the cleartext Flow ID. Signed-off-by: Paul Moore <paul.moore@hp.com> Acked-by: James Morris <jmorris@namei.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[XFRM]: RFC4303 compliant auditingPaul Moore
This patch adds a number of new IPsec audit events to meet the auditing requirements of RFC4303. This includes audit hooks for the following events: * Could not find a valid SA [sections 2.1, 3.4.2] . xfrm_audit_state_notfound() . xfrm_audit_state_notfound_simple() * Sequence number overflow [section 3.3.3] . xfrm_audit_state_replay_overflow() * Replayed packet [section 3.4.3] . xfrm_audit_state_replay() * Integrity check failure [sections 3.4.4.1, 3.4.4.2] . xfrm_audit_state_icvfail() While RFC4304 deals only with ESP most of the changes in this patch apply to IPsec in general, i.e. both AH and ESP. The one case, integrity check failure, where ESP specific code had to be modified the same was done to the AH code for the sake of consistency. Signed-off-by: Paul Moore <paul.moore@hp.com> Acked-by: James Morris <jmorris@namei.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[XFRM]: Support to increment packet dropping statistics.Masahide NAKAMURA
Signed-off-by: Masahide NAKAMURA <nakam@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[IPSEC]: Do xfrm_state_check_space before encapsulationHerbert Xu
While merging the IPsec output path I moved the encapsulation output operation to the top of the loop so that it sits outside of the locked section. Unfortunately in doing so it now sits in front of the space check as well which could be a fatal error. This patch rearranges the calls so that the space check happens as the thing on the output path. This patch also fixes an incorrect goto should the encapsulation output fail. Thanks to Kazunori MIYAZAWA for finding this bug. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[IPSEC]: Kill afinfo->nf_post_routingDavid S. Miller
After changeset: [NETFILTER]: Introduce NF_INET_ hook values It always evaluates to NF_INET_POST_ROUTING. Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[IPSEC]: Add async resume support on outputHerbert Xu
This patch adds support for async resumptions on output. To do so, the transform would return -EINPROGRESS and subsequently invoke the function xfrm_output_resume to resume processing. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[IPSEC]: Merge most of the output pathHerbert Xu
As part of the work on asynchrnous cryptographic operations, we need to be able to resume from the spot where they occur. As such, it helps if we isolate them to one spot. This patch moves most of the remaining family-specific processing into the common output code. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[IPSEC]: Move x->outer_mode->output out of locked sectionHerbert Xu
RO mode is the only one that requires a locked output function. So it's easier to move the lock into that function rather than requiring everyone else to run under the lock. In particular, this allows us to move the size check into the output function without causing a potential dead-lock should the ICMP error somehow hit the same SA on transmission. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[IPSEC]: Use dst->header_len when resizing on outputHerbert Xu
Currently we use x->props.header_len when resizing on output. However, if we're resizing at all we might as well go the whole hog and do it for the whole dst. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-17[IPSEC]: Rename mode to outer_mode and add inner_modeHerbert Xu
This patch adds a new field to xfrm states called inner_mode. The existing mode object is renamed to outer_mode. This is the first part of an attempt to fix inter-family transforms. As it is we always use the outer family when determining which mode to use. As a result we may end up shoving IPv4 packets into netfilter6 and vice versa. What we really want is to use the inner family for the first part of outbound processing and the outer family for the second part. For inbound processing we'd use the opposite pairing. I've also added a check to prevent silly combinations such as transport mode with inter-family transforms. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-17[IPSEC]: Add missing BEET checksHerbert Xu
Currently BEET mode does not reinject the packet back into the stack like tunnel mode does. Since BEET should behave just like tunnel mode this is incorrect. This patch fixes this by introducing a flags field to xfrm_mode that tells the IPsec code whether it should terminate and reinject the packet back into the stack. It then sets the flag for BEET and tunnel mode. I've also added a number of missing BEET checks elsewhere where we check whether a given mode is a tunnel or not. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[IPSEC]: Move state lock into x->type->outputHerbert Xu
This patch releases the lock on the state before calling x->type->output. It also adds the lock to the spots where they're currently needed. Most of those places (all except mip6) are expected to disappear with async crypto. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[IPSEC]: Store IPv6 nh pointer in mac_header on outputHerbert Xu
Current the x->mode->output functions store the IPv6 nh pointer in the skb network header. This is inconvenient because the network header then has to be fixed up before the packet can leave the IPsec stack. The mac header field is unused on output so we can use that to store this instead. This patch does that and removes the network header fix-up in xfrm_output. It also uses ipv6_hdr where appropriate in the x->type->output functions. There is also a minor clean-up in esp4 to make it use the same code as esp6 to help any subsequent effort to merge the two. Lastly it kills two redundant skb_set_* statements in BEET that were simply copied over from transport mode. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[IPSEC]: Move RO-specific output code into xfrm6_mode_ro.cHerbert Xu
The lastused update check in xfrm_output can be done just as well in the mode output function which is specific to RO. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[IPSEC]: Unexport xfrm_replay_notifyHerbert Xu
Now that the only callers of xfrm_replay_notify are in xfrm, we can remove the export. This patch also removes xfrm_aevent_doreplay since it's now called in just one spot. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[IPSEC]: Move output replay code into xfrm_outputHerbert Xu
The replay counter is one of only two remaining things in the output code that requires a lock on the xfrm state (the other being the crypto). This patch moves it into the generic xfrm_output so we can remove the lock from the transforms themselves. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[IPSEC]: Move xfrm_state_check into xfrm_output.cHerbert Xu
The functions xfrm_state_check and xfrm_state_check_space are only used by the output code in xfrm_output.c so we can move them over. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[IPSEC]: Move common output code to xfrm_outputHerbert Xu
Most of the code in xfrm4_output_one and xfrm6_output_one are identical so this patch moves them into a common xfrm_output function which will live in net/xfrm. In fact this would seem to fix a bug as on IPv4 we never reset the network header after a transform which may upset netfilter later on. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>