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 23:27:34 +00:00
|
|
|
/* SPDX-License-Identifier: GPL-2.0 */
|
|
|
|
|
/*
|
|
|
|
|
* Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
|
|
|
|
|
*/
|
|
|
|
|
#ifndef _WG_NOISE_H
|
|
|
|
|
#define _WG_NOISE_H
|
|
|
|
|
|
|
|
|
|
#include "messages.h"
|
|
|
|
|
#include "peerlookup.h"
|
|
|
|
|
|
|
|
|
|
#include <linux/types.h>
|
|
|
|
|
#include <linux/spinlock.h>
|
|
|
|
|
#include <linux/atomic.h>
|
|
|
|
|
#include <linux/rwsem.h>
|
|
|
|
|
#include <linux/mutex.h>
|
|
|
|
|
#include <linux/kref.h>
|
|
|
|
|
|
wireguard: noise: separate receive counter from send counter
In "wireguard: queueing: preserve flow hash across packet scrubbing", we
were required to slightly increase the size of the receive replay
counter to something still fairly small, but an increase nonetheless.
It turns out that we can recoup some of the additional memory overhead
by splitting up the prior union type into two distinct types. Before, we
used the same "noise_counter" union for both sending and receiving, with
sending just using a simple atomic64_t, while receiving used the full
replay counter checker. This meant that most of the memory being
allocated for the sending counter was being wasted. Since the old
"noise_counter" type increased in size in the prior commit, now is a
good time to split up that union type into a distinct "noise_replay_
counter" for receiving and a boring atomic64_t for sending, each using
neither more nor less memory than required.
Also, since sometimes the replay counter is accessed without
necessitating additional accesses to the bitmap, we can reduce cache
misses by hoisting the always-necessary lock above the bitmap in the
struct layout. We also change a "noise_replay_counter" stack allocation
to kmalloc in a -DDEBUG selftest so that KASAN doesn't trigger a stack
frame warning.
All and all, removing a bit of abstraction in this commit makes the code
simpler and smaller, in addition to the motivating memory usage
recuperation. For example, passing around raw "noise_symmetric_key"
structs is something that really only makes sense within noise.c, in the
one place where the sending and receiving keys can safely be thought of
as the same type of object; subsequent to that, it's important that we
uniformly access these through keypair->{sending,receiving}, where their
distinct roles are always made explicit. So this patch allows us to draw
that distinction clearly as well.
Fixes: e7096c131e51 ("net: WireGuard secure network tunnel")
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-20 04:49:30 +00:00
|
|
|
struct noise_replay_counter {
|
|
|
|
|
u64 counter;
|
|
|
|
|
spinlock_t lock;
|
|
|
|
|
unsigned long backtrack[COUNTER_BITS_TOTAL / BITS_PER_LONG];
|
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 23:27:34 +00:00
|
|
|
};
|
|
|
|
|
|
|
|
|
|
struct noise_symmetric_key {
|
|
|
|
|
u8 key[NOISE_SYMMETRIC_KEY_LEN];
|
|
|
|
|
u64 birthdate;
|
|
|
|
|
bool is_valid;
|
|
|
|
|
};
|
|
|
|
|
|
|
|
|
|
struct noise_keypair {
|
|
|
|
|
struct index_hashtable_entry entry;
|
|
|
|
|
struct noise_symmetric_key sending;
|
wireguard: noise: separate receive counter from send counter
In "wireguard: queueing: preserve flow hash across packet scrubbing", we
were required to slightly increase the size of the receive replay
counter to something still fairly small, but an increase nonetheless.
It turns out that we can recoup some of the additional memory overhead
by splitting up the prior union type into two distinct types. Before, we
used the same "noise_counter" union for both sending and receiving, with
sending just using a simple atomic64_t, while receiving used the full
replay counter checker. This meant that most of the memory being
allocated for the sending counter was being wasted. Since the old
"noise_counter" type increased in size in the prior commit, now is a
good time to split up that union type into a distinct "noise_replay_
counter" for receiving and a boring atomic64_t for sending, each using
neither more nor less memory than required.
Also, since sometimes the replay counter is accessed without
necessitating additional accesses to the bitmap, we can reduce cache
misses by hoisting the always-necessary lock above the bitmap in the
struct layout. We also change a "noise_replay_counter" stack allocation
to kmalloc in a -DDEBUG selftest so that KASAN doesn't trigger a stack
frame warning.
All and all, removing a bit of abstraction in this commit makes the code
simpler and smaller, in addition to the motivating memory usage
recuperation. For example, passing around raw "noise_symmetric_key"
structs is something that really only makes sense within noise.c, in the
one place where the sending and receiving keys can safely be thought of
as the same type of object; subsequent to that, it's important that we
uniformly access these through keypair->{sending,receiving}, where their
distinct roles are always made explicit. So this patch allows us to draw
that distinction clearly as well.
Fixes: e7096c131e51 ("net: WireGuard secure network tunnel")
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-20 04:49:30 +00:00
|
|
|
atomic64_t sending_counter;
|
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 23:27:34 +00:00
|
|
|
struct noise_symmetric_key receiving;
|
wireguard: noise: separate receive counter from send counter
In "wireguard: queueing: preserve flow hash across packet scrubbing", we
were required to slightly increase the size of the receive replay
counter to something still fairly small, but an increase nonetheless.
It turns out that we can recoup some of the additional memory overhead
by splitting up the prior union type into two distinct types. Before, we
used the same "noise_counter" union for both sending and receiving, with
sending just using a simple atomic64_t, while receiving used the full
replay counter checker. This meant that most of the memory being
allocated for the sending counter was being wasted. Since the old
"noise_counter" type increased in size in the prior commit, now is a
good time to split up that union type into a distinct "noise_replay_
counter" for receiving and a boring atomic64_t for sending, each using
neither more nor less memory than required.
Also, since sometimes the replay counter is accessed without
necessitating additional accesses to the bitmap, we can reduce cache
misses by hoisting the always-necessary lock above the bitmap in the
struct layout. We also change a "noise_replay_counter" stack allocation
to kmalloc in a -DDEBUG selftest so that KASAN doesn't trigger a stack
frame warning.
All and all, removing a bit of abstraction in this commit makes the code
simpler and smaller, in addition to the motivating memory usage
recuperation. For example, passing around raw "noise_symmetric_key"
structs is something that really only makes sense within noise.c, in the
one place where the sending and receiving keys can safely be thought of
as the same type of object; subsequent to that, it's important that we
uniformly access these through keypair->{sending,receiving}, where their
distinct roles are always made explicit. So this patch allows us to draw
that distinction clearly as well.
Fixes: e7096c131e51 ("net: WireGuard secure network tunnel")
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-20 04:49:30 +00:00
|
|
|
struct noise_replay_counter receiving_counter;
|
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 23:27:34 +00:00
|
|
|
__le32 remote_index;
|
|
|
|
|
bool i_am_the_initiator;
|
|
|
|
|
struct kref refcount;
|
|
|
|
|
struct rcu_head rcu;
|
|
|
|
|
u64 internal_id;
|
|
|
|
|
};
|
|
|
|
|
|
|
|
|
|
struct noise_keypairs {
|
|
|
|
|
struct noise_keypair __rcu *current_keypair;
|
|
|
|
|
struct noise_keypair __rcu *previous_keypair;
|
|
|
|
|
struct noise_keypair __rcu *next_keypair;
|
|
|
|
|
spinlock_t keypair_update_lock;
|
|
|
|
|
};
|
|
|
|
|
|
|
|
|
|
struct noise_static_identity {
|
|
|
|
|
u8 static_public[NOISE_PUBLIC_KEY_LEN];
|
|
|
|
|
u8 static_private[NOISE_PUBLIC_KEY_LEN];
|
|
|
|
|
struct rw_semaphore lock;
|
|
|
|
|
bool has_identity;
|
|
|
|
|
};
|
|
|
|
|
|
|
|
|
|
enum noise_handshake_state {
|
|
|
|
|
HANDSHAKE_ZEROED,
|
|
|
|
|
HANDSHAKE_CREATED_INITIATION,
|
|
|
|
|
HANDSHAKE_CONSUMED_INITIATION,
|
|
|
|
|
HANDSHAKE_CREATED_RESPONSE,
|
|
|
|
|
HANDSHAKE_CONSUMED_RESPONSE
|
|
|
|
|
};
|
|
|
|
|
|
|
|
|
|
struct noise_handshake {
|
|
|
|
|
struct index_hashtable_entry entry;
|
|
|
|
|
|
|
|
|
|
enum noise_handshake_state state;
|
|
|
|
|
u64 last_initiation_consumption;
|
|
|
|
|
|
|
|
|
|
struct noise_static_identity *static_identity;
|
|
|
|
|
|
|
|
|
|
u8 ephemeral_private[NOISE_PUBLIC_KEY_LEN];
|
|
|
|
|
u8 remote_static[NOISE_PUBLIC_KEY_LEN];
|
|
|
|
|
u8 remote_ephemeral[NOISE_PUBLIC_KEY_LEN];
|
|
|
|
|
u8 precomputed_static_static[NOISE_PUBLIC_KEY_LEN];
|
|
|
|
|
|
|
|
|
|
u8 preshared_key[NOISE_SYMMETRIC_KEY_LEN];
|
|
|
|
|
|
|
|
|
|
u8 hash[NOISE_HASH_LEN];
|
|
|
|
|
u8 chaining_key[NOISE_HASH_LEN];
|
|
|
|
|
|
|
|
|
|
u8 latest_timestamp[NOISE_TIMESTAMP_LEN];
|
|
|
|
|
__le32 remote_index;
|
|
|
|
|
|
|
|
|
|
/* Protects all members except the immutable (after noise_handshake_
|
|
|
|
|
* init): remote_static, precomputed_static_static, static_identity.
|
|
|
|
|
*/
|
|
|
|
|
struct rw_semaphore lock;
|
|
|
|
|
};
|
|
|
|
|
|
|
|
|
|
struct wg_device;
|
|
|
|
|
|
|
|
|
|
void wg_noise_init(void);
|
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>
2020-03-19 00:30:47 +00:00
|
|
|
void wg_noise_handshake_init(struct noise_handshake *handshake,
|
|
|
|
|
struct noise_static_identity *static_identity,
|
|
|
|
|
const u8 peer_public_key[NOISE_PUBLIC_KEY_LEN],
|
|
|
|
|
const u8 peer_preshared_key[NOISE_SYMMETRIC_KEY_LEN],
|
|
|
|
|
struct wg_peer *peer);
|
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 23:27:34 +00:00
|
|
|
void wg_noise_handshake_clear(struct noise_handshake *handshake);
|
|
|
|
|
static inline void wg_noise_reset_last_sent_handshake(atomic64_t *handshake_ns)
|
|
|
|
|
{
|
|
|
|
|
atomic64_set(handshake_ns, ktime_get_coarse_boottime_ns() -
|
|
|
|
|
(u64)(REKEY_TIMEOUT + 1) * NSEC_PER_SEC);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
void wg_noise_keypair_put(struct noise_keypair *keypair, bool unreference_now);
|
|
|
|
|
struct noise_keypair *wg_noise_keypair_get(struct noise_keypair *keypair);
|
|
|
|
|
void wg_noise_keypairs_clear(struct noise_keypairs *keypairs);
|
|
|
|
|
bool wg_noise_received_with_keypair(struct noise_keypairs *keypairs,
|
|
|
|
|
struct noise_keypair *received_keypair);
|
|
|
|
|
void wg_noise_expire_current_peer_keypairs(struct wg_peer *peer);
|
|
|
|
|
|
|
|
|
|
void wg_noise_set_static_identity_private_key(
|
|
|
|
|
struct noise_static_identity *static_identity,
|
|
|
|
|
const u8 private_key[NOISE_PUBLIC_KEY_LEN]);
|
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>
2020-03-19 00:30:47 +00:00
|
|
|
void wg_noise_precompute_static_static(struct wg_peer *peer);
|
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 23:27:34 +00:00
|
|
|
|
|
|
|
|
bool
|
|
|
|
|
wg_noise_handshake_create_initiation(struct message_handshake_initiation *dst,
|
|
|
|
|
struct noise_handshake *handshake);
|
|
|
|
|
struct wg_peer *
|
|
|
|
|
wg_noise_handshake_consume_initiation(struct message_handshake_initiation *src,
|
|
|
|
|
struct wg_device *wg);
|
|
|
|
|
|
|
|
|
|
bool wg_noise_handshake_create_response(struct message_handshake_response *dst,
|
|
|
|
|
struct noise_handshake *handshake);
|
|
|
|
|
struct wg_peer *
|
|
|
|
|
wg_noise_handshake_consume_response(struct message_handshake_response *src,
|
|
|
|
|
struct wg_device *wg);
|
|
|
|
|
|
|
|
|
|
bool wg_noise_handshake_begin_session(struct noise_handshake *handshake,
|
|
|
|
|
struct noise_keypairs *keypairs);
|
|
|
|
|
|
|
|
|
|
#endif /* _WG_NOISE_H */
|