aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/net/wireguard/peer.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2020-01-28 16:02:33 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2020-01-28 16:02:33 -0800
commitbd2463ac7d7ec51d432f23bf0e893fb371a908cd (patch)
tree3da32c23be83adb9d9bda7e51b51fa39f69f2447 /drivers/net/wireguard/peer.c
parentMerge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 (diff)
parentnet: phy: add default ARCH_BCM_IPROC for MDIO_BCM_IPROC (diff)
downloadlinux-dev-bd2463ac7d7ec51d432f23bf0e893fb371a908cd.tar.xz
linux-dev-bd2463ac7d7ec51d432f23bf0e893fb371a908cd.zip
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from David Miller: 1) Add WireGuard 2) Add HE and TWT support to ath11k driver, from John Crispin. 3) Add ESP in TCP encapsulation support, from Sabrina Dubroca. 4) Add variable window congestion control to TIPC, from Jon Maloy. 5) Add BCM84881 PHY driver, from Russell King. 6) Start adding netlink support for ethtool operations, from Michal Kubecek. 7) Add XDP drop and TX action support to ena driver, from Sameeh Jubran. 8) Add new ipv4 route notifications so that mlxsw driver does not have to handle identical routes itself. From Ido Schimmel. 9) Add BPF dynamic program extensions, from Alexei Starovoitov. 10) Support RX and TX timestamping in igc, from Vinicius Costa Gomes. 11) Add support for macsec HW offloading, from Antoine Tenart. 12) Add initial support for MPTCP protocol, from Christoph Paasch, Matthieu Baerts, Florian Westphal, Peter Krystad, and many others. 13) Add Octeontx2 PF support, from Sunil Goutham, Geetha sowjanya, Linu Cherian, and others. * git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1469 commits) net: phy: add default ARCH_BCM_IPROC for MDIO_BCM_IPROC udp: segment looped gso packets correctly netem: change mailing list qed: FW 8.42.2.0 debug features qed: rt init valid initialization changed qed: Debug feature: ilt and mdump qed: FW 8.42.2.0 Add fw overlay feature qed: FW 8.42.2.0 HSI changes qed: FW 8.42.2.0 iscsi/fcoe changes qed: Add abstraction for different hsi values per chip qed: FW 8.42.2.0 Additional ll2 type qed: Use dmae to write to widebus registers in fw_funcs qed: FW 8.42.2.0 Parser offsets modified qed: FW 8.42.2.0 Queue Manager changes qed: FW 8.42.2.0 Expose new registers and change windows qed: FW 8.42.2.0 Internal ram offsets modifications MAINTAINERS: Add entry for Marvell OcteonTX2 Physical Function driver Documentation: net: octeontx2: Add RVU HW and drivers overview octeontx2-pf: ethtool RSS config support octeontx2-pf: Add basic ethtool support ...
Diffstat (limited to 'drivers/net/wireguard/peer.c')
-rw-r--r--drivers/net/wireguard/peer.c240
1 files changed, 240 insertions, 0 deletions
diff --git a/drivers/net/wireguard/peer.c b/drivers/net/wireguard/peer.c
new file mode 100644
index 000000000000..071eedf33f5a
--- /dev/null
+++ b/drivers/net/wireguard/peer.c
@@ -0,0 +1,240 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+
+#include "peer.h"
+#include "device.h"
+#include "queueing.h"
+#include "timers.h"
+#include "peerlookup.h"
+#include "noise.h"
+
+#include <linux/kref.h>
+#include <linux/lockdep.h>
+#include <linux/rcupdate.h>
+#include <linux/list.h>
+
+static atomic64_t peer_counter = ATOMIC64_INIT(0);
+
+struct wg_peer *wg_peer_create(struct wg_device *wg,
+ const u8 public_key[NOISE_PUBLIC_KEY_LEN],
+ const u8 preshared_key[NOISE_SYMMETRIC_KEY_LEN])
+{
+ struct wg_peer *peer;
+ int ret = -ENOMEM;
+
+ lockdep_assert_held(&wg->device_update_lock);
+
+ if (wg->num_peers >= MAX_PEERS_PER_DEVICE)
+ return ERR_PTR(ret);
+
+ peer = kzalloc(sizeof(*peer), GFP_KERNEL);
+ if (unlikely(!peer))
+ return ERR_PTR(ret);
+ peer->device = wg;
+
+ if (!wg_noise_handshake_init(&peer->handshake, &wg->static_identity,
+ public_key, preshared_key, peer)) {
+ ret = -EKEYREJECTED;
+ goto err_1;
+ }
+ if (dst_cache_init(&peer->endpoint_cache, GFP_KERNEL))
+ goto err_1;
+ if (wg_packet_queue_init(&peer->tx_queue, wg_packet_tx_worker, false,
+ MAX_QUEUED_PACKETS))
+ goto err_2;
+ if (wg_packet_queue_init(&peer->rx_queue, NULL, false,
+ MAX_QUEUED_PACKETS))
+ goto err_3;
+
+ peer->internal_id = atomic64_inc_return(&peer_counter);
+ peer->serial_work_cpu = nr_cpumask_bits;
+ wg_cookie_init(&peer->latest_cookie);
+ wg_timers_init(peer);
+ wg_cookie_checker_precompute_peer_keys(peer);
+ spin_lock_init(&peer->keypairs.keypair_update_lock);
+ INIT_WORK(&peer->transmit_handshake_work,
+ wg_packet_handshake_send_worker);
+ rwlock_init(&peer->endpoint_lock);
+ kref_init(&peer->refcount);
+ skb_queue_head_init(&peer->staged_packet_queue);
+ wg_noise_reset_last_sent_handshake(&peer->last_sent_handshake);
+ set_bit(NAPI_STATE_NO_BUSY_POLL, &peer->napi.state);
+ netif_napi_add(wg->dev, &peer->napi, wg_packet_rx_poll,
+ NAPI_POLL_WEIGHT);
+ napi_enable(&peer->napi);
+ list_add_tail(&peer->peer_list, &wg->peer_list);
+ INIT_LIST_HEAD(&peer->allowedips_list);
+ wg_pubkey_hashtable_add(wg->peer_hashtable, peer);
+ ++wg->num_peers;
+ pr_debug("%s: Peer %llu created\n", wg->dev->name, peer->internal_id);
+ return peer;
+
+err_3:
+ wg_packet_queue_free(&peer->tx_queue, false);
+err_2:
+ dst_cache_destroy(&peer->endpoint_cache);
+err_1:
+ kfree(peer);
+ return ERR_PTR(ret);
+}
+
+struct wg_peer *wg_peer_get_maybe_zero(struct wg_peer *peer)
+{
+ RCU_LOCKDEP_WARN(!rcu_read_lock_bh_held(),
+ "Taking peer reference without holding the RCU read lock");
+ if (unlikely(!peer || !kref_get_unless_zero(&peer->refcount)))
+ return NULL;
+ return peer;
+}
+
+static void peer_make_dead(struct wg_peer *peer)
+{
+ /* Remove from configuration-time lookup structures. */
+ list_del_init(&peer->peer_list);
+ wg_allowedips_remove_by_peer(&peer->device->peer_allowedips, peer,
+ &peer->device->device_update_lock);
+ wg_pubkey_hashtable_remove(peer->device->peer_hashtable, peer);
+
+ /* Mark as dead, so that we don't allow jumping contexts after. */
+ WRITE_ONCE(peer->is_dead, true);
+
+ /* The caller must now synchronize_rcu() for this to take effect. */
+}
+
+static void peer_remove_after_dead(struct wg_peer *peer)
+{
+ WARN_ON(!peer->is_dead);
+
+ /* No more keypairs can be created for this peer, since is_dead protects
+ * add_new_keypair, so we can now destroy existing ones.
+ */
+ wg_noise_keypairs_clear(&peer->keypairs);
+
+ /* Destroy all ongoing timers that were in-flight at the beginning of
+ * this function.
+ */
+ wg_timers_stop(peer);
+
+ /* The transition between packet encryption/decryption queues isn't
+ * guarded by is_dead, but each reference's life is strictly bounded by
+ * two generations: once for parallel crypto and once for serial
+ * ingestion, so we can simply flush twice, and be sure that we no
+ * longer have references inside these queues.
+ */
+
+ /* a) For encrypt/decrypt. */
+ flush_workqueue(peer->device->packet_crypt_wq);
+ /* b.1) For send (but not receive, since that's napi). */
+ flush_workqueue(peer->device->packet_crypt_wq);
+ /* b.2.1) For receive (but not send, since that's wq). */
+ napi_disable(&peer->napi);
+ /* b.2.1) It's now safe to remove the napi struct, which must be done
+ * here from process context.
+ */
+ netif_napi_del(&peer->napi);
+
+ /* Ensure any workstructs we own (like transmit_handshake_work or
+ * clear_peer_work) no longer are in use.
+ */
+ flush_workqueue(peer->device->handshake_send_wq);
+
+ /* After the above flushes, a peer might still be active in a few
+ * different contexts: 1) from xmit(), before hitting is_dead and
+ * returning, 2) from wg_packet_consume_data(), before hitting is_dead
+ * and returning, 3) from wg_receive_handshake_packet() after a point
+ * where it has processed an incoming handshake packet, but where
+ * all calls to pass it off to timers fails because of is_dead. We won't
+ * have new references in (1) eventually, because we're removed from
+ * allowedips; we won't have new references in (2) eventually, because
+ * wg_index_hashtable_lookup will always return NULL, since we removed
+ * all existing keypairs and no more can be created; we won't have new
+ * references in (3) eventually, because we're removed from the pubkey
+ * hash table, which allows for a maximum of one handshake response,
+ * via the still-uncleared index hashtable entry, but not more than one,
+ * and in wg_cookie_message_consume, the lookup eventually gets a peer
+ * with a refcount of zero, so no new reference is taken.
+ */
+
+ --peer->device->num_peers;
+ wg_peer_put(peer);
+}
+
+/* We have a separate "remove" function make sure that all active places where
+ * a peer is currently operating will eventually come to an end and not pass
+ * their reference onto another context.
+ */
+void wg_peer_remove(struct wg_peer *peer)
+{
+ if (unlikely(!peer))
+ return;
+ lockdep_assert_held(&peer->device->device_update_lock);
+
+ peer_make_dead(peer);
+ synchronize_rcu();
+ peer_remove_after_dead(peer);
+}
+
+void wg_peer_remove_all(struct wg_device *wg)
+{
+ struct wg_peer *peer, *temp;
+ LIST_HEAD(dead_peers);
+
+ lockdep_assert_held(&wg->device_update_lock);
+
+ /* Avoid having to traverse individually for each one. */
+ wg_allowedips_free(&wg->peer_allowedips, &wg->device_update_lock);
+
+ list_for_each_entry_safe(peer, temp, &wg->peer_list, peer_list) {
+ peer_make_dead(peer);
+ list_add_tail(&peer->peer_list, &dead_peers);
+ }
+ synchronize_rcu();
+ list_for_each_entry_safe(peer, temp, &dead_peers, peer_list)
+ peer_remove_after_dead(peer);
+}
+
+static void rcu_release(struct rcu_head *rcu)
+{
+ struct wg_peer *peer = container_of(rcu, struct wg_peer, rcu);
+
+ dst_cache_destroy(&peer->endpoint_cache);
+ wg_packet_queue_free(&peer->rx_queue, false);
+ wg_packet_queue_free(&peer->tx_queue, false);
+
+ /* The final zeroing takes care of clearing any remaining handshake key
+ * material and other potentially sensitive information.
+ */
+ kzfree(peer);
+}
+
+static void kref_release(struct kref *refcount)
+{
+ struct wg_peer *peer = container_of(refcount, struct wg_peer, refcount);
+
+ pr_debug("%s: Peer %llu (%pISpfsc) destroyed\n",
+ peer->device->dev->name, peer->internal_id,
+ &peer->endpoint.addr);
+
+ /* Remove ourself from dynamic runtime lookup structures, now that the
+ * last reference is gone.
+ */
+ wg_index_hashtable_remove(peer->device->index_hashtable,
+ &peer->handshake.entry);
+
+ /* Remove any lingering packets that didn't have a chance to be
+ * transmitted.
+ */
+ wg_packet_purge_staged_packets(peer);
+
+ /* Free the memory used. */
+ call_rcu(&peer->rcu, rcu_release);
+}
+
+void wg_peer_put(struct wg_peer *peer)
+{
+ if (unlikely(!peer))
+ return;
+ kref_put(&peer->refcount, kref_release);
+}