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2020-09-09noise: take lock when removing handshake entry from tableJason A. Donenfeld
Eric reported that syzkaller found a race of this variety: CPU 1 CPU 2 -------------------------------------------|--------------------------------------- wg_index_hashtable_replace(old, ...) | if (hlist_unhashed(&old->index_hash)) | | wg_index_hashtable_remove(old) | hlist_del_init_rcu(&old->index_hash) | old->index_hash.pprev = NULL hlist_replace_rcu(&old->index_hash, ...) | *old->index_hash.pprev | Syzbot wasn't actually able to reproduce this more than once or create a reproducer, because the race window between checking "hlist_unhashed" and calling "hlist_replace_rcu" is just so small. Adding an mdelay(5) or similar there helps make this demonstrable using this simple script: #!/bin/bash set -ex trap 'kill $pid1; kill $pid2; ip link del wg0; ip link del wg1' EXIT ip link add wg0 type wireguard ip link add wg1 type wireguard wg set wg0 private-key <(wg genkey) listen-port 9999 wg set wg1 private-key <(wg genkey) peer $(wg show wg0 public-key) endpoint 127.0.0.1:9999 persistent-keepalive 1 wg set wg0 peer $(wg show wg1 public-key) ip link set wg0 up yes link set wg1 up | ip -force -batch - & pid1=$! yes link set wg1 down | ip -force -batch - & pid2=$! wait The fundumental underlying problem is that we permit calls to wg_index_ hashtable_remove(handshake.entry) without requiring the caller to take the handshake mutex that is intended to protect members of handshake during mutations. This is consistently the case with calls to wg_index_ hashtable_insert(handshake.entry) and wg_index_hashtable_replace( handshake.entry), but it's missing from a pertinent callsite of wg_ index_hashtable_remove(handshake.entry). So, this patch makes sure that mutex is taken. The original code was a little bit funky though, in the form of: remove(handshake.entry) lock(), memzero(handshake.some_members), unlock() remove(handshake.entry) The original intention of that double removal pattern outside the lock appears to be some attempt to prevent insertions that might happen while locks are dropped during expensive crypto operations, but actually, all callers of wg_index_hashtable_insert(handshake.entry) take the write lock and then explicitly check handshake.state, as they should, which the aforementioned memzero clears, which means an insertion should already be impossible. And regardless, the original intention was necessarily racy, since it wasn't guaranteed that something else would run after the unlock() instead of after the remove(). So, from a soundness perspective, it seems positive to remove what looks like a hack at best. The crash from both syzbot and from the script above is as follows: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 0 PID: 7395 Comm: kworker/0:3 Not tainted 5.9.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: wg-kex-wg1 wg_packet_handshake_receive_worker RIP: 0010:hlist_replace_rcu include/linux/rculist.h:505 [inline] RIP: 0010:wg_index_hashtable_replace+0x176/0x330 drivers/net/wireguard/peerlookup.c:174 Code: 00 fc ff df 48 89 f9 48 c1 e9 03 80 3c 01 00 0f 85 44 01 00 00 48 b9 00 00 00 00 00 fc ff df 48 8b 45 10 48 89 c6 48 c1 ee 03 <80> 3c 0e 00 0f 85 06 01 00 00 48 85 d2 4c 89 28 74 47 e8 a3 4f b5 RSP: 0018:ffffc90006a97bf8 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff888050ffc4f8 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88808e04e010 RBP: ffff88808e04e000 R08: 0000000000000001 R09: ffff8880543d0000 R10: ffffed100a87a000 R11: 000000000000016e R12: ffff8880543d0000 R13: ffff88808e04e008 R14: ffff888050ffc508 R15: ffff888050ffc500 FS: 0000000000000000(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000f5505db0 CR3: 0000000097cf7000 CR4: 00000000001526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: wg_noise_handshake_begin_session+0x752/0xc9a drivers/net/wireguard/noise.c:820 wg_receive_handshake_packet drivers/net/wireguard/receive.c:183 [inline] wg_packet_handshake_receive_worker+0x33b/0x730 drivers/net/wireguard/receive.c:220 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3b5/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Note that this fixes the same issue as the previous commit, but in a more direct way. Upstream, the commit message of that previous commit has been changed to: wireguard: peerlookup: take lock before checking hash in replace operation Eric's suggested fix for the previous commit's mentioned race condition was to simply take the table->lock in wg_index_hashtable_replace(). The table->lock of the hash table is supposed to protect the bucket heads, not the entires, but actually, since all the mutator functions are already taking it, it makes sense to take it too for the test to hlist_unhashed, as a defense in depth measure, so that it no longer races with deletions, regardless of what other locks are protecting individual entries. This is sensible from a performance perspective because, as Eric pointed out, the case of being unhashed is already the unlikely case, so this won't add common contention. And comparing instructions, this basically doesn't make much of a difference other than pushing and popping %r13, used by the new `bool ret`. More generally, I like the idea of locking consistency across table mutator functions, and this might let me rest slightly easier at night. Since we've already tagged it, we're not going to change it at this point, but I include mention of it here for reference. Reported-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2020-08-27compat: backport kfree_sensitive and switch to itJason A. Donenfeld
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2020-06-21noise: do not assign initiation time in if conditionFrank Werner-Krippendorf
Fixes an error condition reported by checkpatch.pl which caused by assigning a variable in an if condition in wg_noise_handshake_consume_ initiation(). Signed-off-by: Frank Werner-Krippendorf <mail@hb9fxq.ch> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2020-05-19noise: separate receive counter from send counterJason A. Donenfeld
In "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. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2020-05-19noise: read preshared key while taking lockJason A. Donenfeld
Prior we read the preshared key after dropping the handshake lock, which isn't an actual crypto issue if it races, but it's still not quite correct. So copy that part of the state into a temporary like we do with the rest of the handshake state variables. Then we can release the lock, operate on the temporary, and zero it out at the end of the function. In performance tests, the impact of this was entirely unnoticable, probably because those bytes are coming from the same cacheline as other things that are being copied out in the same manner. Reported-by: Matt Dunwoodie <ncon@noconroy.net> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2020-03-18noise: error out precomputed DH during handshake rather than configJason A. Donenfeld
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>
2020-02-05noise: reject peers with low order public keysJason A. Donenfeld
Our static-static calculation returns a failure if the public key is of low order. We check for this when peers are added, and don't allow them to be added if they're low order, except in the case where we haven't yet been given a private key. In that case, we would defer the removal of the peer until we're given a private key, since at that point we're doing new static-static calculations which incur failures we can act on. This meant, however, that we wound up removing peers rather late in the configuration flow. Syzkaller points out that peer_remove calls flush_workqueue, which in turn might then wait for sending a handshake initiation to complete. Since handshake initiation needs the static identity lock, holding the static identity lock while calling peer_remove can result in a rare deadlock. We have precisely this case in this situation of late-stage peer removal based on an invalid public key. We can't drop the lock when removing, because then incoming handshakes might interact with a bogus static-static calculation. While the band-aid patch for this would involve breaking up the peer removal into two steps like wg_peer_remove_all does, in order to solve the locking issue, there's actually a much more elegant way of fixing this: If the static-static calculation succeeds with one private key, it *must* succeed with all others, because all 32-byte strings map to valid private keys, thanks to clamping. That means we can get rid of this silly dance and locking headaches of removing peers late in the configuration flow, and instead just reject them early on, regardless of whether the device has yet been assigned a private key. For the case where the device doesn't yet have a private key, we safely use zeros just for the purposes of checking for low order points by way of checking the output of the calculation. The following PoC will trigger the deadlock: ip link add wg0 type wireguard ip addr add 10.0.0.1/24 dev wg0 ip link set wg0 up ping -f 10.0.0.2 & while true; do wg set wg0 private-key /dev/null peer AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA= allowed-ips 10.0.0.0/24 endpoint 10.0.0.3:1234 wg set wg0 private-key <(echo AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA=) done [ 0.949105] ====================================================== [ 0.949550] WARNING: possible circular locking dependency detected [ 0.950143] 5.5.0-debug+ #18 Not tainted [ 0.950431] ------------------------------------------------------ [ 0.950959] wg/89 is trying to acquire lock: [ 0.951252] ffff8880333e2128 ((wq_completion)wg-kex-wg0){+.+.}, at: flush_workqueue+0xe3/0x12f0 [ 0.951865] [ 0.951865] but task is already holding lock: [ 0.952280] ffff888032819bc0 (&wg->static_identity.lock){++++}, at: wg_set_device+0x95d/0xcc0 [ 0.953011] [ 0.953011] which lock already depends on the new lock. [ 0.953011] [ 0.953651] [ 0.953651] the existing dependency chain (in reverse order) is: [ 0.954292] [ 0.954292] -> #2 (&wg->static_identity.lock){++++}: [ 0.954804] lock_acquire+0x127/0x350 [ 0.955133] down_read+0x83/0x410 [ 0.955428] wg_noise_handshake_create_initiation+0x97/0x700 [ 0.955885] wg_packet_send_handshake_initiation+0x13a/0x280 [ 0.956401] wg_packet_handshake_send_worker+0x10/0x20 [ 0.956841] process_one_work+0x806/0x1500 [ 0.957167] worker_thread+0x8c/0xcb0 [ 0.957549] kthread+0x2ee/0x3b0 [ 0.957792] ret_from_fork+0x24/0x30 [ 0.958234] [ 0.958234] -> #1 ((work_completion)(&peer->transmit_handshake_work)){+.+.}: [ 0.958808] lock_acquire+0x127/0x350 [ 0.959075] process_one_work+0x7ab/0x1500 [ 0.959369] worker_thread+0x8c/0xcb0 [ 0.959639] kthread+0x2ee/0x3b0 [ 0.959896] ret_from_fork+0x24/0x30 [ 0.960346] [ 0.960346] -> #0 ((wq_completion)wg-kex-wg0){+.+.}: [ 0.960945] check_prev_add+0x167/0x1e20 [ 0.961351] __lock_acquire+0x2012/0x3170 [ 0.961725] lock_acquire+0x127/0x350 [ 0.961990] flush_workqueue+0x106/0x12f0 [ 0.962280] peer_remove_after_dead+0x160/0x220 [ 0.962600] wg_set_device+0xa24/0xcc0 [ 0.962994] genl_rcv_msg+0x52f/0xe90 [ 0.963298] netlink_rcv_skb+0x111/0x320 [ 0.963618] genl_rcv+0x1f/0x30 [ 0.963853] netlink_unicast+0x3f6/0x610 [ 0.964245] netlink_sendmsg+0x700/0xb80 [ 0.964586] __sys_sendto+0x1dd/0x2c0 [ 0.964854] __x64_sys_sendto+0xd8/0x1b0 [ 0.965141] do_syscall_64+0x90/0xd9a [ 0.965408] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 0.965769] [ 0.965769] other info that might help us debug this: [ 0.965769] [ 0.966337] Chain exists of: [ 0.966337] (wq_completion)wg-kex-wg0 --> (work_completion)(&peer->transmit_handshake_work) --> &wg->static_identity.lock [ 0.966337] [ 0.967417] Possible unsafe locking scenario: [ 0.967417] [ 0.967836] CPU0 CPU1 [ 0.968155] ---- ---- [ 0.968497] lock(&wg->static_identity.lock); [ 0.968779] lock((work_completion)(&peer->transmit_handshake_work)); [ 0.969345] lock(&wg->static_identity.lock); [ 0.969809] lock((wq_completion)wg-kex-wg0); [ 0.970146] [ 0.970146] *** DEADLOCK *** [ 0.970146] [ 0.970531] 5 locks held by wg/89: [ 0.970908] #0: ffffffff827433c8 (cb_lock){++++}, at: genl_rcv+0x10/0x30 [ 0.971400] #1: ffffffff82743480 (genl_mutex){+.+.}, at: genl_rcv_msg+0x642/0xe90 [ 0.971924] #2: ffffffff827160c0 (rtnl_mutex){+.+.}, at: wg_set_device+0x9f/0xcc0 [ 0.972488] #3: ffff888032819de0 (&wg->device_update_lock){+.+.}, at: wg_set_device+0xb0/0xcc0 [ 0.973095] #4: ffff888032819bc0 (&wg->static_identity.lock){++++}, at: wg_set_device+0x95d/0xcc0 [ 0.973653] [ 0.973653] stack backtrace: [ 0.973932] CPU: 1 PID: 89 Comm: wg Not tainted 5.5.0-debug+ #18 [ 0.974476] Call Trace: [ 0.974638] dump_stack+0x97/0xe0 [ 0.974869] check_noncircular+0x312/0x3e0 [ 0.975132] ? print_circular_bug+0x1f0/0x1f0 [ 0.975410] ? __kernel_text_address+0x9/0x30 [ 0.975727] ? unwind_get_return_address+0x51/0x90 [ 0.976024] check_prev_add+0x167/0x1e20 [ 0.976367] ? graph_lock+0x70/0x160 [ 0.976682] __lock_acquire+0x2012/0x3170 [ 0.976998] ? register_lock_class+0x1140/0x1140 [ 0.977323] lock_acquire+0x127/0x350 [ 0.977627] ? flush_workqueue+0xe3/0x12f0 [ 0.977890] flush_workqueue+0x106/0x12f0 [ 0.978147] ? flush_workqueue+0xe3/0x12f0 [ 0.978410] ? find_held_lock+0x2c/0x110 [ 0.978662] ? lock_downgrade+0x6e0/0x6e0 [ 0.978919] ? queue_rcu_work+0x60/0x60 [ 0.979166] ? netif_napi_del+0x151/0x3b0 [ 0.979501] ? peer_remove_after_dead+0x160/0x220 [ 0.979871] peer_remove_after_dead+0x160/0x220 [ 0.980232] wg_set_device+0xa24/0xcc0 [ 0.980516] ? deref_stack_reg+0x8e/0xc0 [ 0.980801] ? set_peer+0xe10/0xe10 [ 0.981040] ? __ww_mutex_check_waiters+0x150/0x150 [ 0.981430] ? __nla_validate_parse+0x163/0x270 [ 0.981719] ? genl_family_rcv_msg_attrs_parse+0x13f/0x310 [ 0.982078] genl_rcv_msg+0x52f/0xe90 [ 0.982348] ? genl_family_rcv_msg_attrs_parse+0x310/0x310 [ 0.982690] ? register_lock_class+0x1140/0x1140 [ 0.983049] netlink_rcv_skb+0x111/0x320 [ 0.983298] ? genl_family_rcv_msg_attrs_parse+0x310/0x310 [ 0.983645] ? netlink_ack+0x880/0x880 [ 0.983888] genl_rcv+0x1f/0x30 [ 0.984168] netlink_unicast+0x3f6/0x610 [ 0.984443] ? netlink_detachskb+0x60/0x60 [ 0.984729] ? find_held_lock+0x2c/0x110 [ 0.984976] netlink_sendmsg+0x700/0xb80 [ 0.985220] ? netlink_broadcast_filtered+0xa60/0xa60 [ 0.985533] __sys_sendto+0x1dd/0x2c0 [ 0.985763] ? __x64_sys_getpeername+0xb0/0xb0 [ 0.986039] ? sockfd_lookup_light+0x17/0x160 [ 0.986397] ? __sys_recvmsg+0x8c/0xf0 [ 0.986711] ? __sys_recvmsg_sock+0xd0/0xd0 [ 0.987018] __x64_sys_sendto+0xd8/0x1b0 [ 0.987283] ? lockdep_hardirqs_on+0x39b/0x5a0 [ 0.987666] do_syscall_64+0x90/0xd9a [ 0.987903] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 0.988223] RIP: 0033:0x7fe77c12003e [ 0.988508] Code: c3 8b 07 85 c0 75 24 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 4 [ 0.989666] RSP: 002b:00007fffada2ed58 EFLAGS: 00000246 ORIG_RAX: 000000000000002c [ 0.990137] RAX: ffffffffffffffda RBX: 00007fe77c159d48 RCX: 00007fe77c12003e [ 0.990583] RDX: 0000000000000040 RSI: 000055fd1d38e020 RDI: 0000000000000004 [ 0.991091] RBP: 000055fd1d38e020 R08: 000055fd1cb63358 R09: 000000000000000c [ 0.991568] R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000002c [ 0.992014] R13: 0000000000000004 R14: 000055fd1d38e020 R15: 0000000000000001 Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Reported-by: syzbot <syzkaller@googlegroups.com>
2019-10-11noise: recompare stamps after taking write lockJason A. Donenfeld
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2019-07-11noise: immediately rekey all peers after changing device private keyJason A. Donenfeld
Reported-by: Derrick Pallas <derrick@pallas.us> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2019-06-25global: switch to coarse ktimeJason A. Donenfeld
Coarse ktime is broken until [1] in 5.2 and kernels without the backport, so we use fallback code there. The fallback code has also been improved significantly. It now only uses slower clocks on kernels < 3.17, at the expense of some accuracy we're not overly concerned about. [1] https://lore.kernel.org/lkml/tip-e3ff9c3678b4d80e22d2557b68726174578eaf52@git.kernel.org/ Suggested-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2019-03-27blake2s: remove outlen parameter from finalJason A. Donenfeld
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2019-03-25peerlookup: rename from hashtablesJason A. Donenfeld
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2019-03-17global: the _bh variety of rcu helpers have been unifiedJason A. Donenfeld
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2019-02-03noise: store clamped key instead of raw keyJason A. Donenfeld
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2019-02-03hashtables: decouple hashtable allocations from the main device allocationSultan Alsawaf
The hashtable allocations are quite large, and cause the device allocation in the net framework to stall sometimes while it tries to find a contiguous region that can fit the device struct: [<0000000000000000>] __switch_to+0x94/0xb8 [<0000000000000000>] __alloc_pages_nodemask+0x764/0x7e8 [<0000000000000000>] kmalloc_order+0x20/0x40 [<0000000000000000>] __kmalloc+0x144/0x1a0 [<0000000000000000>] alloc_netdev_mqs+0x5c/0x368 [<0000000000000000>] rtnl_create_link+0x48/0x180 [<0000000000000000>] rtnl_newlink+0x410/0x708 [<0000000000000000>] rtnetlink_rcv_msg+0x190/0x1f8 [<0000000000000000>] netlink_rcv_skb+0x4c/0xf8 [<0000000000000000>] rtnetlink_rcv+0x30/0x40 [<0000000000000000>] netlink_unicast+0x18c/0x208 [<0000000000000000>] netlink_sendmsg+0x19c/0x348 [<0000000000000000>] sock_sendmsg+0x3c/0x58 [<0000000000000000>] ___sys_sendmsg+0x290/0x2b0 [<0000000000000000>] __sys_sendmsg+0x58/0xa0 [<0000000000000000>] SyS_sendmsg+0x10/0x20 [<0000000000000000>] el0_svc_naked+0x34/0x38 [<0000000000000000>] 0xffffffffffffffff To fix the allocation stalls, decouple the hashtable allocations from the device allocation and allocate the hashtables with kvmalloc's implicit __GFP_NORETRY so that the allocations fall back to vmalloc with little resistance. Signed-off-by: Sultan Alsawaf <sultan@kerneltoast.com> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2019-02-03noise: whiten the nanoseconds portion of the timestampJason A. Donenfeld
This mitigates unrelated sidechannel attacks that think they can turn WireGuard into a useful time oracle. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2019-01-23noise: replace getnstimeofday64 with ktime_get_real_ts64Jason A. Donenfeld
The former was just a wrapper around the latter, and so upstream is now removing it. Also adjust the compat kludge to deal with this. Reported-by: Alex Xu <alex@alxu.ca> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2019-01-07global: update copyrightJason A. Donenfeld
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2018-11-13global: various formatting tweeksJason A. Donenfeld
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2018-10-25global: do not allow compiler to reorder is_valid or is_deadJason A. Donenfeld
Suggested-by: Jann Horn <jann@thejh.net> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2018-10-25peer: another peer_remove cleanupJason A. Donenfeld
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2018-10-09global: give if statements brackets and other cleanupsJason A. Donenfeld
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2018-10-08global: more nitsJason A. Donenfeld
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2018-10-08global: rename struct wireguard_ to struct wg_Jason A. Donenfeld
This required a bit of pruning of our christmas trees. Suggested-by: Jiri Pirko <jiri@resnulli.us> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2018-10-02global: change BUG_ON to WARN_ONJason A. Donenfeld
Suggested-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2018-10-02global: prefix all functions with wg_Jason A. Donenfeld
I understand why this must be done, though I'm not so happy about having to do it. In some places, it puts us over 80 chars and we have to break lines up in further ugly ways. And in general, I think this makes things harder to read. Yet another thing we must do to please upstream. Maybe this can be replaced in the future by some kind of automatic module namespacing logic in the linker, or even combined with LTO and aggressive symbol stripping. Suggested-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2018-09-25crypto: make constant naming scheme consistentJason A. Donenfeld
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2018-09-20global: put SPDX identifier on its own lineJason A. Donenfeld
The kernel has very specific rules correlating file type with comment type, and also SPDX identifiers can't be merged with other comments. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2018-09-04global: prefer sizeof(*pointer) when possibleJason A. Donenfeld
Suggested-by: Sultan Alsawaf <sultanxda@gmail.com> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2018-08-28global: run through clang-formatJason A. Donenfeld
This is the worst commit in the whole repo, making the code much less readable, but so it goes with upstream maintainers. We are now woefully wrapped at 80 columns. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2018-08-03peer: ensure destruction doesn't raceJason A. Donenfeld
Completely rework peer removal to ensure peers don't jump between contexts and create races. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2018-08-02noise: free peer references on failureJason A. Donenfeld
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2018-08-02cookie: returned keypair might disappear if rcu lock not heldJason A. Donenfeld
And in general it's good to prefer dereferencing entry.peer from a handshake object rather than a keypair object, when possible, since keypairs could disappear before their underlying peer. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2018-08-01allowedips: prevent double read in krefJason A. Donenfeld
Blocks like: if (node_placement(*trie, key, cidr, bits, &node, lock)) { node->peer = peer; return 0; } May result in a double read when adjusting the refcount, in the highly unlikely case of LTO and an overly smart compiler. While we're at it, replace rcu_assign_pointer(X, NULL); with RCU_INIT_POINTER. Reported-by: Jann Horn <jann@thejh.net> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2018-07-31noise: use hex constant for tai64n offsetJason A. Donenfeld
Suggested-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2018-06-23global: use fast boottime instead of normal boottimeJason A. Donenfeld
Generally if we're inaccurate by a few nanoseconds, it doesn't matter. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2018-06-23global: use ktime boottime instead of jiffiesJason A. Donenfeld
Since this is a network protocol, expirations need to be accounted for, even across system suspend. On real systems, this isn't a problem, since we're clearing all keys before suspend. But on Android, where we don't do that, this is something of a problem. So, we switch to using boottime instead of jiffies. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2018-06-18noise: wait for crng before taking locksJason A. Donenfeld
Otherwise, get_random_bytes_wait gets called from curve25519_generate_secret, and at the same time, a user might use the wg(8) utility, which then wants to grab a read lock for what we're write locking. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2018-06-18netlink: maintain static_identity lock over entire private key updateJason A. Donenfeld
We don't want the local private key to not correspond with a precomputed ss or precomputed cookie hash at any intermediate point. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2018-06-18noise: take locks for ss precomputationJason A. Donenfeld
Usually this is called from handshake_init, where locking doesn't matter because nothing references it yet, but it's also called when changing the device private key, so it's probably a good thing to not process a handshake with a ss precomputation that's part old and part new. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2018-01-03global: year bumpJason A. Donenfeld
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2017-12-09global: add SPDX tags to all filesGreg Kroah-Hartman
It's good to have SPDX identifiers in all files as the Linux kernel developers are working to add these identifiers to all files. Update all files with the correct SPDX license identifier based on the license text of the project or based on the license in the file itself. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Modified-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2017-11-22global: switch from timeval to timespecJason A. Donenfeld
This gets us nanoseconds instead of microseconds, which is better, and we can do this pretty much without freaking out existing userspace, which doesn't actually make use of the nano/micro seconds field: zx2c4@thinkpad ~ $ cat a.c void main() { puts(sizeof(struct timeval) == sizeof(struct timespec) ? "success" : "failure"); } zx2c4@thinkpad ~ $ gcc a.c -m64 && ./a.out success zx2c4@thinkpad ~ $ gcc a.c -m32 && ./a.out success This doesn't solve y2038 problem, but timespec64 isn't yet a thing in userspace. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2017-11-02global: revert checkpatch.pl changesJason A. Donenfeld
These changes were suggested by checkpatch.pl, but actually cause big problems depending on the options. Revert. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2017-10-31global: use fewer BUG_ONsJason A. Donenfeld
Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2017-10-31global: style nitsJason A. Donenfeld
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2017-10-31global: accept decent check_patch.pl suggestionsJason A. Donenfeld
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2017-10-17noise: no need to take the RCU lock if we're not dereferencingJason A. Donenfeld
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2017-10-17noise: handshake constants can be read-only after initJason A. Donenfeld
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2017-10-03global: add space around variable declarationsJason A. Donenfeld
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>