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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/timers.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-bd2463ac7d7ec51d432f23bf0e893fb371a908cd.tar.xz
linux-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/timers.c')
-rw-r--r--drivers/net/wireguard/timers.c243
1 files changed, 243 insertions, 0 deletions
diff --git a/drivers/net/wireguard/timers.c b/drivers/net/wireguard/timers.c
new file mode 100644
index 000000000000..d54d32ac9bc4
--- /dev/null
+++ b/drivers/net/wireguard/timers.c
@@ -0,0 +1,243 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+
+#include "timers.h"
+#include "device.h"
+#include "peer.h"
+#include "queueing.h"
+#include "socket.h"
+
+/*
+ * - Timer for retransmitting the handshake if we don't hear back after
+ * `REKEY_TIMEOUT + jitter` ms.
+ *
+ * - Timer for sending empty packet if we have received a packet but after have
+ * not sent one for `KEEPALIVE_TIMEOUT` ms.
+ *
+ * - Timer for initiating new handshake if we have sent a packet but after have
+ * not received one (even empty) for `(KEEPALIVE_TIMEOUT + REKEY_TIMEOUT) +
+ * jitter` ms.
+ *
+ * - Timer for zeroing out all ephemeral keys after `(REJECT_AFTER_TIME * 3)` ms
+ * if no new keys have been received.
+ *
+ * - Timer for, if enabled, sending an empty authenticated packet every user-
+ * specified seconds.
+ */
+
+static inline void mod_peer_timer(struct wg_peer *peer,
+ struct timer_list *timer,
+ unsigned long expires)
+{
+ rcu_read_lock_bh();
+ if (likely(netif_running(peer->device->dev) &&
+ !READ_ONCE(peer->is_dead)))
+ mod_timer(timer, expires);
+ rcu_read_unlock_bh();
+}
+
+static void wg_expired_retransmit_handshake(struct timer_list *timer)
+{
+ struct wg_peer *peer = from_timer(peer, timer,
+ timer_retransmit_handshake);
+
+ if (peer->timer_handshake_attempts > MAX_TIMER_HANDSHAKES) {
+ pr_debug("%s: Handshake for peer %llu (%pISpfsc) did not complete after %d attempts, giving up\n",
+ peer->device->dev->name, peer->internal_id,
+ &peer->endpoint.addr, MAX_TIMER_HANDSHAKES + 2);
+
+ del_timer(&peer->timer_send_keepalive);
+ /* We drop all packets without a keypair and don't try again,
+ * if we try unsuccessfully for too long to make a handshake.
+ */
+ wg_packet_purge_staged_packets(peer);
+
+ /* We set a timer for destroying any residue that might be left
+ * of a partial exchange.
+ */
+ if (!timer_pending(&peer->timer_zero_key_material))
+ mod_peer_timer(peer, &peer->timer_zero_key_material,
+ jiffies + REJECT_AFTER_TIME * 3 * HZ);
+ } else {
+ ++peer->timer_handshake_attempts;
+ pr_debug("%s: Handshake for peer %llu (%pISpfsc) did not complete after %d seconds, retrying (try %d)\n",
+ peer->device->dev->name, peer->internal_id,
+ &peer->endpoint.addr, REKEY_TIMEOUT,
+ peer->timer_handshake_attempts + 1);
+
+ /* We clear the endpoint address src address, in case this is
+ * the cause of trouble.
+ */
+ wg_socket_clear_peer_endpoint_src(peer);
+
+ wg_packet_send_queued_handshake_initiation(peer, true);
+ }
+}
+
+static void wg_expired_send_keepalive(struct timer_list *timer)
+{
+ struct wg_peer *peer = from_timer(peer, timer, timer_send_keepalive);
+
+ wg_packet_send_keepalive(peer);
+ if (peer->timer_need_another_keepalive) {
+ peer->timer_need_another_keepalive = false;
+ mod_peer_timer(peer, &peer->timer_send_keepalive,
+ jiffies + KEEPALIVE_TIMEOUT * HZ);
+ }
+}
+
+static void wg_expired_new_handshake(struct timer_list *timer)
+{
+ struct wg_peer *peer = from_timer(peer, timer, timer_new_handshake);
+
+ pr_debug("%s: Retrying handshake with peer %llu (%pISpfsc) because we stopped hearing back after %d seconds\n",
+ peer->device->dev->name, peer->internal_id,
+ &peer->endpoint.addr, KEEPALIVE_TIMEOUT + REKEY_TIMEOUT);
+ /* We clear the endpoint address src address, in case this is the cause
+ * of trouble.
+ */
+ wg_socket_clear_peer_endpoint_src(peer);
+ wg_packet_send_queued_handshake_initiation(peer, false);
+}
+
+static void wg_expired_zero_key_material(struct timer_list *timer)
+{
+ struct wg_peer *peer = from_timer(peer, timer, timer_zero_key_material);
+
+ rcu_read_lock_bh();
+ if (!READ_ONCE(peer->is_dead)) {
+ wg_peer_get(peer);
+ if (!queue_work(peer->device->handshake_send_wq,
+ &peer->clear_peer_work))
+ /* If the work was already on the queue, we want to drop
+ * the extra reference.
+ */
+ wg_peer_put(peer);
+ }
+ rcu_read_unlock_bh();
+}
+
+static void wg_queued_expired_zero_key_material(struct work_struct *work)
+{
+ struct wg_peer *peer = container_of(work, struct wg_peer,
+ clear_peer_work);
+
+ pr_debug("%s: Zeroing out all keys for peer %llu (%pISpfsc), since we haven't received a new one in %d seconds\n",
+ peer->device->dev->name, peer->internal_id,
+ &peer->endpoint.addr, REJECT_AFTER_TIME * 3);
+ wg_noise_handshake_clear(&peer->handshake);
+ wg_noise_keypairs_clear(&peer->keypairs);
+ wg_peer_put(peer);
+}
+
+static void wg_expired_send_persistent_keepalive(struct timer_list *timer)
+{
+ struct wg_peer *peer = from_timer(peer, timer,
+ timer_persistent_keepalive);
+
+ if (likely(peer->persistent_keepalive_interval))
+ wg_packet_send_keepalive(peer);
+}
+
+/* Should be called after an authenticated data packet is sent. */
+void wg_timers_data_sent(struct wg_peer *peer)
+{
+ if (!timer_pending(&peer->timer_new_handshake))
+ mod_peer_timer(peer, &peer->timer_new_handshake,
+ jiffies + (KEEPALIVE_TIMEOUT + REKEY_TIMEOUT) * HZ +
+ prandom_u32_max(REKEY_TIMEOUT_JITTER_MAX_JIFFIES));
+}
+
+/* Should be called after an authenticated data packet is received. */
+void wg_timers_data_received(struct wg_peer *peer)
+{
+ if (likely(netif_running(peer->device->dev))) {
+ if (!timer_pending(&peer->timer_send_keepalive))
+ mod_peer_timer(peer, &peer->timer_send_keepalive,
+ jiffies + KEEPALIVE_TIMEOUT * HZ);
+ else
+ peer->timer_need_another_keepalive = true;
+ }
+}
+
+/* Should be called after any type of authenticated packet is sent, whether
+ * keepalive, data, or handshake.
+ */
+void wg_timers_any_authenticated_packet_sent(struct wg_peer *peer)
+{
+ del_timer(&peer->timer_send_keepalive);
+}
+
+/* Should be called after any type of authenticated packet is received, whether
+ * keepalive, data, or handshake.
+ */
+void wg_timers_any_authenticated_packet_received(struct wg_peer *peer)
+{
+ del_timer(&peer->timer_new_handshake);
+}
+
+/* Should be called after a handshake initiation message is sent. */
+void wg_timers_handshake_initiated(struct wg_peer *peer)
+{
+ mod_peer_timer(peer, &peer->timer_retransmit_handshake,
+ jiffies + REKEY_TIMEOUT * HZ +
+ prandom_u32_max(REKEY_TIMEOUT_JITTER_MAX_JIFFIES));
+}
+
+/* Should be called after a handshake response message is received and processed
+ * or when getting key confirmation via the first data message.
+ */
+void wg_timers_handshake_complete(struct wg_peer *peer)
+{
+ del_timer(&peer->timer_retransmit_handshake);
+ peer->timer_handshake_attempts = 0;
+ peer->sent_lastminute_handshake = false;
+ ktime_get_real_ts64(&peer->walltime_last_handshake);
+}
+
+/* Should be called after an ephemeral key is created, which is before sending a
+ * handshake response or after receiving a handshake response.
+ */
+void wg_timers_session_derived(struct wg_peer *peer)
+{
+ mod_peer_timer(peer, &peer->timer_zero_key_material,
+ jiffies + REJECT_AFTER_TIME * 3 * HZ);
+}
+
+/* Should be called before a packet with authentication, whether
+ * keepalive, data, or handshakem is sent, or after one is received.
+ */
+void wg_timers_any_authenticated_packet_traversal(struct wg_peer *peer)
+{
+ if (peer->persistent_keepalive_interval)
+ mod_peer_timer(peer, &peer->timer_persistent_keepalive,
+ jiffies + peer->persistent_keepalive_interval * HZ);
+}
+
+void wg_timers_init(struct wg_peer *peer)
+{
+ timer_setup(&peer->timer_retransmit_handshake,
+ wg_expired_retransmit_handshake, 0);
+ timer_setup(&peer->timer_send_keepalive, wg_expired_send_keepalive, 0);
+ timer_setup(&peer->timer_new_handshake, wg_expired_new_handshake, 0);
+ timer_setup(&peer->timer_zero_key_material,
+ wg_expired_zero_key_material, 0);
+ timer_setup(&peer->timer_persistent_keepalive,
+ wg_expired_send_persistent_keepalive, 0);
+ INIT_WORK(&peer->clear_peer_work, wg_queued_expired_zero_key_material);
+ peer->timer_handshake_attempts = 0;
+ peer->sent_lastminute_handshake = false;
+ peer->timer_need_another_keepalive = false;
+}
+
+void wg_timers_stop(struct wg_peer *peer)
+{
+ del_timer_sync(&peer->timer_retransmit_handshake);
+ del_timer_sync(&peer->timer_send_keepalive);
+ del_timer_sync(&peer->timer_new_handshake);
+ del_timer_sync(&peer->timer_zero_key_material);
+ del_timer_sync(&peer->timer_persistent_keepalive);
+ flush_work(&peer->clear_peer_work);
+}