Commit Graph

21 Commits

Author SHA1 Message Date
Jason A. Donenfeld af8afcf1fd wireguard: selftests: check that route_me_harder packets use the right sk
If netfilter changes the packet mark, the packet is rerouted. The
ip_route_me_harder family of functions fails to use the right sk, opting
to instead use skb->sk, resulting in a routing loop when used with
tunnels. With the next change fixing this issue in netfilter, test for
the relevant condition inside our test suite, since wireguard was where
the bug was discovered.

Reported-by: Chen Minqiang <ptpt52@gmail.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2020-10-30 12:57:38 +01:00
Jason A. Donenfeld 900575aa33 wireguard: device: avoid circular netns references
Before, we took a reference to the creating netns if the new netns was
different. This caused issues with circular references, with two
wireguard interfaces swapping namespaces. The solution is to rather not
take any extra references at all, but instead simply invalidate the
creating netns pointer when that netns is deleted.

In order to prevent this from happening again, this commit improves the
rough object leak tracking by allowing it to account for created and
destroyed interfaces, aside from just peers and keys. That then makes it
possible to check for the object leak when having two interfaces take a
reference to each others' namespaces.

Fixes: e7096c131e ("net: WireGuard secure network tunnel")
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-23 14:50:34 -07:00
Linus Torvalds 533b220f7b arm64 updates for 5.8
- Branch Target Identification (BTI)
 	* Support for ARMv8.5-BTI in both user- and kernel-space. This
 	  allows branch targets to limit the types of branch from which
 	  they can be called and additionally prevents branching to
 	  arbitrary code, although kernel support requires a very recent
 	  toolchain.
 
 	* Function annotation via SYM_FUNC_START() so that assembly
 	  functions are wrapped with the relevant "landing pad"
 	  instructions.
 
 	* BPF and vDSO updates to use the new instructions.
 
 	* Addition of a new HWCAP and exposure of BTI capability to
 	  userspace via ID register emulation, along with ELF loader
 	  support for the BTI feature in .note.gnu.property.
 
 	* Non-critical fixes to CFI unwind annotations in the sigreturn
 	  trampoline.
 
 - Shadow Call Stack (SCS)
 	* Support for Clang's Shadow Call Stack feature, which reserves
 	  platform register x18 to point at a separate stack for each
 	  task that holds only return addresses. This protects function
 	  return control flow from buffer overruns on the main stack.
 
 	* Save/restore of x18 across problematic boundaries (user-mode,
 	  hypervisor, EFI, suspend, etc).
 
 	* Core support for SCS, should other architectures want to use it
 	  too.
 
 	* SCS overflow checking on context-switch as part of the existing
 	  stack limit check if CONFIG_SCHED_STACK_END_CHECK=y.
 
 - CPU feature detection
 	* Removed numerous "SANITY CHECK" errors when running on a system
 	  with mismatched AArch32 support at EL1. This is primarily a
 	  concern for KVM, which disabled support for 32-bit guests on
 	  such a system.
 
 	* Addition of new ID registers and fields as the architecture has
 	  been extended.
 
 - Perf and PMU drivers
 	* Minor fixes and cleanups to system PMU drivers.
 
 - Hardware errata
 	* Unify KVM workarounds for VHE and nVHE configurations.
 
 	* Sort vendor errata entries in Kconfig.
 
 - Secure Monitor Call Calling Convention (SMCCC)
 	* Update to the latest specification from Arm (v1.2).
 
 	* Allow PSCI code to query the SMCCC version.
 
 - Software Delegated Exception Interface (SDEI)
 	* Unexport a bunch of unused symbols.
 
 	* Minor fixes to handling of firmware data.
 
 - Pointer authentication
 	* Add support for dumping the kernel PAC mask in vmcoreinfo so
 	  that the stack can be unwound by tools such as kdump.
 
 	* Simplification of key initialisation during CPU bringup.
 
 - BPF backend
 	* Improve immediate generation for logical and add/sub
 	  instructions.
 
 - vDSO
 	- Minor fixes to the linker flags for consistency with other
 	  architectures and support for LLVM's unwinder.
 
 	- Clean up logic to initialise and map the vDSO into userspace.
 
 - ACPI
 	- Work around for an ambiguity in the IORT specification relating
 	  to the "num_ids" field.
 
 	- Support _DMA method for all named components rather than only
 	  PCIe root complexes.
 
 	- Minor other IORT-related fixes.
 
 - Miscellaneous
 	* Initialise debug traps early for KGDB and fix KDB cacheflushing
 	  deadlock.
 
 	* Minor tweaks to early boot state (documentation update, set
 	  TEXT_OFFSET to 0x0, increase alignment of PE/COFF sections).
 
 	* Refactoring and cleanup
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 updates from Will Deacon:
 "A sizeable pile of arm64 updates for 5.8.

  Summary below, but the big two features are support for Branch Target
  Identification and Clang's Shadow Call stack. The latter is currently
  arm64-only, but the high-level parts are all in core code so it could
  easily be adopted by other architectures pending toolchain support

  Branch Target Identification (BTI):

   - Support for ARMv8.5-BTI in both user- and kernel-space. This allows
     branch targets to limit the types of branch from which they can be
     called and additionally prevents branching to arbitrary code,
     although kernel support requires a very recent toolchain.

   - Function annotation via SYM_FUNC_START() so that assembly functions
     are wrapped with the relevant "landing pad" instructions.

   - BPF and vDSO updates to use the new instructions.

   - Addition of a new HWCAP and exposure of BTI capability to userspace
     via ID register emulation, along with ELF loader support for the
     BTI feature in .note.gnu.property.

   - Non-critical fixes to CFI unwind annotations in the sigreturn
     trampoline.

  Shadow Call Stack (SCS):

   - Support for Clang's Shadow Call Stack feature, which reserves
     platform register x18 to point at a separate stack for each task
     that holds only return addresses. This protects function return
     control flow from buffer overruns on the main stack.

   - Save/restore of x18 across problematic boundaries (user-mode,
     hypervisor, EFI, suspend, etc).

   - Core support for SCS, should other architectures want to use it
     too.

   - SCS overflow checking on context-switch as part of the existing
     stack limit check if CONFIG_SCHED_STACK_END_CHECK=y.

  CPU feature detection:

   - Removed numerous "SANITY CHECK" errors when running on a system
     with mismatched AArch32 support at EL1. This is primarily a concern
     for KVM, which disabled support for 32-bit guests on such a system.

   - Addition of new ID registers and fields as the architecture has
     been extended.

  Perf and PMU drivers:

   - Minor fixes and cleanups to system PMU drivers.

  Hardware errata:

   - Unify KVM workarounds for VHE and nVHE configurations.

   - Sort vendor errata entries in Kconfig.

  Secure Monitor Call Calling Convention (SMCCC):

   - Update to the latest specification from Arm (v1.2).

   - Allow PSCI code to query the SMCCC version.

  Software Delegated Exception Interface (SDEI):

   - Unexport a bunch of unused symbols.

   - Minor fixes to handling of firmware data.

  Pointer authentication:

   - Add support for dumping the kernel PAC mask in vmcoreinfo so that
     the stack can be unwound by tools such as kdump.

   - Simplification of key initialisation during CPU bringup.

  BPF backend:

   - Improve immediate generation for logical and add/sub instructions.

  vDSO:

   - Minor fixes to the linker flags for consistency with other
     architectures and support for LLVM's unwinder.

   - Clean up logic to initialise and map the vDSO into userspace.

  ACPI:

   - Work around for an ambiguity in the IORT specification relating to
     the "num_ids" field.

   - Support _DMA method for all named components rather than only PCIe
     root complexes.

   - Minor other IORT-related fixes.

  Miscellaneous:

   - Initialise debug traps early for KGDB and fix KDB cacheflushing
     deadlock.

   - Minor tweaks to early boot state (documentation update, set
     TEXT_OFFSET to 0x0, increase alignment of PE/COFF sections).

   - Refactoring and cleanup"

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (148 commits)
  KVM: arm64: Move __load_guest_stage2 to kvm_mmu.h
  KVM: arm64: Check advertised Stage-2 page size capability
  arm64/cpufeature: Add get_arm64_ftr_reg_nowarn()
  ACPI/IORT: Remove the unused __get_pci_rid()
  arm64/cpuinfo: Add ID_MMFR4_EL1 into the cpuinfo_arm64 context
  arm64/cpufeature: Add remaining feature bits in ID_AA64PFR1 register
  arm64/cpufeature: Add remaining feature bits in ID_AA64PFR0 register
  arm64/cpufeature: Add remaining feature bits in ID_AA64ISAR0 register
  arm64/cpufeature: Add remaining feature bits in ID_MMFR4 register
  arm64/cpufeature: Add remaining feature bits in ID_PFR0 register
  arm64/cpufeature: Introduce ID_MMFR5 CPU register
  arm64/cpufeature: Introduce ID_DFR1 CPU register
  arm64/cpufeature: Introduce ID_PFR2 CPU register
  arm64/cpufeature: Make doublelock a signed feature in ID_AA64DFR0
  arm64/cpufeature: Drop TraceFilt feature exposure from ID_DFR0 register
  arm64/cpufeature: Add explicit ftr_id_isar0[] for ID_ISAR0 register
  arm64: mm: Add asid_gen_match() helper
  firmware: smccc: Fix missing prototype warning for arm_smccc_version_init
  arm64: vdso: Fix CFI directives in sigreturn trampoline
  arm64: vdso: Don't prefix sigreturn trampoline with a BTI C instruction
  ...
2020-06-01 15:18:27 -07:00
Jason A. Donenfeld ee3c1aa3f3 wireguard: selftests: use newer iproute2 for gcc-10
gcc-10 switched to defaulting to -fno-common, which broke iproute2-5.4.
This was fixed in iproute-5.6, so switch to that. Because we're after a
stable testing surface, we generally don't like to bump these
unnecessarily, but in this case, being able to actually build is a basic
necessity.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-20 20:55:09 -07:00
Kees Cook 8d58f222e8 ubsan: disable UBSAN_ALIGNMENT under COMPILE_TEST
The documentation for UBSAN_ALIGNMENT already mentions that it should
not be used on all*config builds (and for efficient-unaligned-access
architectures), so just refactor the Kconfig to correctly implement this
so randconfigs will stop creating insane images that freak out objtool
under CONFIG_UBSAN_TRAP (due to the false positives producing functions
that never return, etc).

Link: http://lkml.kernel.org/r/202005011433.C42EA3E2D@keescook
Fixes: 0887a7ebc9 ("ubsan: add trap instrumentation option")
Signed-off-by: Kees Cook <keescook@chromium.org>
Reported-by: Randy Dunlap <rdunlap@infradead.org>
  Link: https://lore.kernel.org/linux-next/202004231224.D6B3B650@keescook/
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-07 19:27:21 -07:00
Jason A. Donenfeld b673e24aad wireguard: socket: remove errant restriction on looping to self
It's already possible to create two different interfaces and loop
packets between them. This has always been possible with tunnels in the
kernel, and isn't specific to wireguard. Therefore, the networking stack
already needs to deal with that. At the very least, the packet winds up
exceeding the MTU and is discarded at that point. So, since this is
already something that happens, there's no need to forbid the not very
exceptional case of routing a packet back to the same interface; this
loop is no different than others, and we shouldn't special case it, but
rather rely on generic handling of loops in general. This also makes it
easier to do interesting things with wireguard such as onion routing.

At the same time, we add a selftest for this, ensuring that both onion
routing works and infinite routing loops do not crash the kernel. We
also add a test case for wireguard interfaces nesting packets and
sending traffic between each other, as well as the loop in this case
too. We make sure to send some throughput-heavy traffic for this use
case, to stress out any possible recursion issues with the locks around
workqueues.

Fixes: e7096c131e ("net: WireGuard secure network tunnel")
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-06 20:03:47 -07:00
Jason A. Donenfeld a0fd7cc87a wireguard: selftests: use normal kernel stack size on ppc64
While at some point it might have made sense to be running these tests
on ppc64 with 4k stacks, the kernel hasn't actually used 4k stacks on
64-bit powerpc in a long time, and more interesting things that we test
don't really work when we deviate from the default (16k). So, we stop
pushing our luck in this commit, and return to the default instead of
the minimum.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-06 20:03:47 -07:00
Borislav Petkov 593309423c x86/32: Remove CONFIG_DOUBLEFAULT
Make the doublefault exception handler unconditional on 32-bit. Yes,
it is important to be able to catch #DF exceptions instead of silent
reboots. Yes, the code size increase is worth every byte. And one less
CONFIG symbol is just the cherry on top.

No functional changes.

Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200404083646.8897-1-bp@alien8.de
2020-04-14 14:24:05 +02:00
Linus Torvalds ff2ae607c6 SPDX patches for 5.7-rc1.
Here are 3 SPDX patches for 5.7-rc1.
 
 One fixes up the SPDX tag for a single driver, while the other two go
 through the tree and add SPDX tags for all of the .gitignore files as
 needed.
 
 Nothing too complex, but you will get a merge conflict with your current
 tree, that should be trivial to handle (one file modified by two things,
 one file deleted.)
 
 All 3 of these have been in linux-next for a while, with no reported
 issues other than the merge conflict.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'spdx-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx

Pull SPDX updates from Greg KH:
 "Here are three SPDX patches for 5.7-rc1.

  One fixes up the SPDX tag for a single driver, while the other two go
  through the tree and add SPDX tags for all of the .gitignore files as
  needed.

  Nothing too complex, but you will get a merge conflict with your
  current tree, that should be trivial to handle (one file modified by
  two things, one file deleted.)

  All three of these have been in linux-next for a while, with no
  reported issues other than the merge conflict"

* tag 'spdx-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx:
  ASoC: MT6660: make spdxcheck.py happy
  .gitignore: add SPDX License Identifier
  .gitignore: remove too obvious comments
2020-04-03 13:12:26 -07:00
Masahiro Yamada d198b34f38 .gitignore: add SPDX License Identifier
Add SPDX License Identifier to all .gitignore files.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-25 11:50:48 +01:00
Jason A. Donenfeld 11a7686aa9 wireguard: noise: error out precomputed DH during handshake rather than config
We precompute the static-static ECDH during configuration time, in order
to save an expensive computation later when receiving network packets.
However, not all ECDH computations yield a contributory result. Prior,
we were just not letting those peers be added to the interface. However,
this creates a strange inconsistency, since it was still possible to add
other weird points, like a valid public key plus a low-order point, and,
like points that result in zeros, a handshake would not complete. In
order to make the behavior more uniform and less surprising, simply
allow all peers to be added. Then, we'll error out later when doing the
crypto if there's an issue. This also adds more separation between the
crypto layer and the configuration layer.

Discussed-with: Mathias Hall-Andersen <mathias@hall-andersen.dk>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-18 18:51:43 -07:00
Jason A. Donenfeld 551599edbf wireguard: selftests: test using new 64-bit time_t
In case this helps expose bugs with the newer 64-bit time_t types, we do
our testing with the newer musl that supports this as well as
CONFIG_COMPAT_32BIT_TIME=n. This matters to us, since wireguard does in
fact deal with timestamps.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-18 18:51:43 -07:00
YueHaibing 166391159c wireguard: selftests: remove duplicated include <sys/types.h>
This commit removes a duplicated include.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-18 18:51:43 -07:00
Jason A. Donenfeld 04ddf1208f wireguard: selftests: reduce complexity and fix make races
This gives us fewer dependencies and shortens build time, fixes up some
hash checking race conditions, and also fixes missing directory creation
that caused issues on massively parallel builds.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-16 19:21:56 -08:00
Jason A. Donenfeld a12d7f3cbd wireguard: device: use icmp_ndo_send helper
Because wireguard is calling icmp from network device context, it should
use the ndo helper so that the rate limiting applies correctly.  This
commit adds a small test to the wireguard test suite to ensure that the
new functions continue doing the right thing in the context of
wireguard. It does this by setting up a condition that will definately
evoke an icmp error message from the driver, but along a nat'd path.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-13 14:19:00 -08:00
Jason A. Donenfeld 88f404a9b1 wireguard: selftests: tie socket waiting to target pid
Without this, we wind up proceeding too early sometimes when the
previous process has just used the same listening port. So, we tie the
listening socket query to the specific pid we're interested in.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-05 14:14:18 +01:00
Krzysztof Kozlowski 4a2ef721e6 wireguard: selftests: cleanup CONFIG_ENABLE_WARN_DEPRECATED
CONFIG_ENABLE_WARN_DEPRECATED is gone since commit 771c035372
("deprecate the '__deprecated' attribute warnings entirely and for
good").

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-05 14:14:18 +01:00
Jason A. Donenfeld f9398acba6 wireguard: selftests: ensure non-addition of peers with failed precomputation
Ensure that peers with low order points are ignored, both in the case
where we already have a device private key and in the case where we do
not. This adds points that naturally give a zero output.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-05 14:14:18 +01:00
Jason A. Donenfeld 9a69a4c880 wireguard: selftests: remove ancient kernel compatibility code
Quite a bit of the test suite was designed to work with ancient kernels.
Thankfully we no longer have to deal with this. This commit updates
things that we can finally update and removes things that we can finally
remove, to avoid the build-up of the last several years as a result of
having to support ancient kernels. We can finally rely on suppress_
prefixlength being available. On the build side of things, the no-PIE
hack is no longer required, and we can bump some of the tools, repair
our m68k and i686-kvm support, and get better coverage of the static
branches used in the crypto lib and in udp_tunnel.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-01-05 14:08:32 -08:00
Jason A. Donenfeld 65d88d0411 wireguard: selftests: import harness makefile for test suite
WireGuard has been using this on build.wireguard.com for the last
several years with considerable success. It allows for very quick and
iterative development cycles, and supports several platforms.

To run the test suite on your current platform in QEMU:

  $ make -C tools/testing/selftests/wireguard/qemu -j$(nproc)

To run it with KASAN and such turned on:

  $ DEBUG_KERNEL=yes make -C tools/testing/selftests/wireguard/qemu -j$(nproc)

To run it emulated for another platform in QEMU:

  $ ARCH=arm make -C tools/testing/selftests/wireguard/qemu -j$(nproc)

At the moment, we support aarch64_be, aarch64, arm, armeb, i686, m68k,
mips64, mips64el, mips, mipsel, powerpc64le, powerpc, and x86_64.

The system supports incremental rebuilding, so it should be very fast to
change a single file and then test it out and have immediate feedback.

This requires for the right toolchain and qemu to be installed prior.
I've had success with those from musl.cc.

This is tailored for WireGuard at the moment, though later projects
might generalize it for other network testing.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-12-16 19:22:22 -08:00
Jason A. Donenfeld e7096c131e net: WireGuard secure network tunnel
WireGuard is a layer 3 secure networking tunnel made specifically for
the kernel, that aims to be much simpler and easier to audit than IPsec.
Extensive documentation and description of the protocol and
considerations, along with formal proofs of the cryptography, are
available at:

  * https://www.wireguard.com/
  * https://www.wireguard.com/papers/wireguard.pdf

This commit implements WireGuard as a simple network device driver,
accessible in the usual RTNL way used by virtual network drivers. It
makes use of the udp_tunnel APIs, GRO, GSO, NAPI, and the usual set of
networking subsystem APIs. It has a somewhat novel multicore queueing
system designed for maximum throughput and minimal latency of encryption
operations, but it is implemented modestly using workqueues and NAPI.
Configuration is done via generic Netlink, and following a review from
the Netlink maintainer a year ago, several high profile userspace tools
have already implemented the API.

This commit also comes with several different tests, both in-kernel
tests and out-of-kernel tests based on network namespaces, taking profit
of the fact that sockets used by WireGuard intentionally stay in the
namespace the WireGuard interface was originally created, exactly like
the semantics of userspace tun devices. See wireguard.com/netns/ for
pictures and examples.

The source code is fairly short, but rather than combining everything
into a single file, WireGuard is developed as cleanly separable files,
making auditing and comprehension easier. Things are laid out as
follows:

  * noise.[ch], cookie.[ch], messages.h: These implement the bulk of the
    cryptographic aspects of the protocol, and are mostly data-only in
    nature, taking in buffers of bytes and spitting out buffers of
    bytes. They also handle reference counting for their various shared
    pieces of data, like keys and key lists.

  * ratelimiter.[ch]: Used as an integral part of cookie.[ch] for
    ratelimiting certain types of cryptographic operations in accordance
    with particular WireGuard semantics.

  * allowedips.[ch], peerlookup.[ch]: The main lookup structures of
    WireGuard, the former being trie-like with particular semantics, an
    integral part of the design of the protocol, and the latter just
    being nice helper functions around the various hashtables we use.

  * device.[ch]: Implementation of functions for the netdevice and for
    rtnl, responsible for maintaining the life of a given interface and
    wiring it up to the rest of WireGuard.

  * peer.[ch]: Each interface has a list of peers, with helper functions
    available here for creation, destruction, and reference counting.

  * socket.[ch]: Implementation of functions related to udp_socket and
    the general set of kernel socket APIs, for sending and receiving
    ciphertext UDP packets, and taking care of WireGuard-specific sticky
    socket routing semantics for the automatic roaming.

  * netlink.[ch]: Userspace API entry point for configuring WireGuard
    peers and devices. The API has been implemented by several userspace
    tools and network management utility, and the WireGuard project
    distributes the basic wg(8) tool.

  * queueing.[ch]: Shared function on the rx and tx path for handling
    the various queues used in the multicore algorithms.

  * send.c: Handles encrypting outgoing packets in parallel on
    multiple cores, before sending them in order on a single core, via
    workqueues and ring buffers. Also handles sending handshake and cookie
    messages as part of the protocol, in parallel.

  * receive.c: Handles decrypting incoming packets in parallel on
    multiple cores, before passing them off in order to be ingested via
    the rest of the networking subsystem with GRO via the typical NAPI
    poll function. Also handles receiving handshake and cookie messages
    as part of the protocol, in parallel.

  * timers.[ch]: Uses the timer wheel to implement protocol particular
    event timeouts, and gives a set of very simple event-driven entry
    point functions for callers.

  * main.c, version.h: Initialization and deinitialization of the module.

  * selftest/*.h: Runtime unit tests for some of the most security
    sensitive functions.

  * tools/testing/selftests/wireguard/netns.sh: Aforementioned testing
    script using network namespaces.

This commit aims to be as self-contained as possible, implementing
WireGuard as a standalone module not needing much special handling or
coordination from the network subsystem. I expect for future
optimizations to the network stack to positively improve WireGuard, and
vice-versa, but for the time being, this exists as intentionally
standalone.

We introduce a menu option for CONFIG_WIREGUARD, as well as providing a
verbose debug log and self-tests via CONFIG_WIREGUARD_DEBUG.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Cc: David Miller <davem@davemloft.net>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: linux-crypto@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: netdev@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-12-08 17:48:42 -08:00