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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /drivers/net/wireguard/ratelimiter.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
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Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
Diffstat (limited to 'drivers/net/wireguard/ratelimiter.c')
-rw-r--r--drivers/net/wireguard/ratelimiter.c223
1 files changed, 223 insertions, 0 deletions
diff --git a/drivers/net/wireguard/ratelimiter.c b/drivers/net/wireguard/ratelimiter.c
new file mode 100644
index 000000000..dd55e5c26
--- /dev/null
+++ b/drivers/net/wireguard/ratelimiter.c
@@ -0,0 +1,223 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+
+#include "ratelimiter.h"
+#include <linux/siphash.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <net/ip.h>
+
+static struct kmem_cache *entry_cache;
+static hsiphash_key_t key;
+static spinlock_t table_lock = __SPIN_LOCK_UNLOCKED("ratelimiter_table_lock");
+static DEFINE_MUTEX(init_lock);
+static u64 init_refcnt; /* Protected by init_lock, hence not atomic. */
+static atomic_t total_entries = ATOMIC_INIT(0);
+static unsigned int max_entries, table_size;
+static void wg_ratelimiter_gc_entries(struct work_struct *);
+static DECLARE_DEFERRABLE_WORK(gc_work, wg_ratelimiter_gc_entries);
+static struct hlist_head *table_v4;
+#if IS_ENABLED(CONFIG_IPV6)
+static struct hlist_head *table_v6;
+#endif
+
+struct ratelimiter_entry {
+ u64 last_time_ns, tokens, ip;
+ void *net;
+ spinlock_t lock;
+ struct hlist_node hash;
+ struct rcu_head rcu;
+};
+
+enum {
+ PACKETS_PER_SECOND = 20,
+ PACKETS_BURSTABLE = 5,
+ PACKET_COST = NSEC_PER_SEC / PACKETS_PER_SECOND,
+ TOKEN_MAX = PACKET_COST * PACKETS_BURSTABLE
+};
+
+static void entry_free(struct rcu_head *rcu)
+{
+ kmem_cache_free(entry_cache,
+ container_of(rcu, struct ratelimiter_entry, rcu));
+ atomic_dec(&total_entries);
+}
+
+static void entry_uninit(struct ratelimiter_entry *entry)
+{
+ hlist_del_rcu(&entry->hash);
+ call_rcu(&entry->rcu, entry_free);
+}
+
+/* Calling this function with a NULL work uninits all entries. */
+static void wg_ratelimiter_gc_entries(struct work_struct *work)
+{
+ const u64 now = ktime_get_coarse_boottime_ns();
+ struct ratelimiter_entry *entry;
+ struct hlist_node *temp;
+ unsigned int i;
+
+ for (i = 0; i < table_size; ++i) {
+ spin_lock(&table_lock);
+ hlist_for_each_entry_safe(entry, temp, &table_v4[i], hash) {
+ if (unlikely(!work) ||
+ now - entry->last_time_ns > NSEC_PER_SEC)
+ entry_uninit(entry);
+ }
+#if IS_ENABLED(CONFIG_IPV6)
+ hlist_for_each_entry_safe(entry, temp, &table_v6[i], hash) {
+ if (unlikely(!work) ||
+ now - entry->last_time_ns > NSEC_PER_SEC)
+ entry_uninit(entry);
+ }
+#endif
+ spin_unlock(&table_lock);
+ if (likely(work))
+ cond_resched();
+ }
+ if (likely(work))
+ queue_delayed_work(system_power_efficient_wq, &gc_work, HZ);
+}
+
+bool wg_ratelimiter_allow(struct sk_buff *skb, struct net *net)
+{
+ /* We only take the bottom half of the net pointer, so that we can hash
+ * 3 words in the end. This way, siphash's len param fits into the final
+ * u32, and we don't incur an extra round.
+ */
+ const u32 net_word = (unsigned long)net;
+ struct ratelimiter_entry *entry;
+ struct hlist_head *bucket;
+ u64 ip;
+
+ if (skb->protocol == htons(ETH_P_IP)) {
+ ip = (u64 __force)ip_hdr(skb)->saddr;
+ bucket = &table_v4[hsiphash_2u32(net_word, ip, &key) &
+ (table_size - 1)];
+ }
+#if IS_ENABLED(CONFIG_IPV6)
+ else if (skb->protocol == htons(ETH_P_IPV6)) {
+ /* Only use 64 bits, so as to ratelimit the whole /64. */
+ memcpy(&ip, &ipv6_hdr(skb)->saddr, sizeof(ip));
+ bucket = &table_v6[hsiphash_3u32(net_word, ip >> 32, ip, &key) &
+ (table_size - 1)];
+ }
+#endif
+ else
+ return false;
+ rcu_read_lock();
+ hlist_for_each_entry_rcu(entry, bucket, hash) {
+ if (entry->net == net && entry->ip == ip) {
+ u64 now, tokens;
+ bool ret;
+ /* Quasi-inspired by nft_limit.c, but this is actually a
+ * slightly different algorithm. Namely, we incorporate
+ * the burst as part of the maximum tokens, rather than
+ * as part of the rate.
+ */
+ spin_lock(&entry->lock);
+ now = ktime_get_coarse_boottime_ns();
+ tokens = min_t(u64, TOKEN_MAX,
+ entry->tokens + now -
+ entry->last_time_ns);
+ entry->last_time_ns = now;
+ ret = tokens >= PACKET_COST;
+ entry->tokens = ret ? tokens - PACKET_COST : tokens;
+ spin_unlock(&entry->lock);
+ rcu_read_unlock();
+ return ret;
+ }
+ }
+ rcu_read_unlock();
+
+ if (atomic_inc_return(&total_entries) > max_entries)
+ goto err_oom;
+
+ entry = kmem_cache_alloc(entry_cache, GFP_KERNEL);
+ if (unlikely(!entry))
+ goto err_oom;
+
+ entry->net = net;
+ entry->ip = ip;
+ INIT_HLIST_NODE(&entry->hash);
+ spin_lock_init(&entry->lock);
+ entry->last_time_ns = ktime_get_coarse_boottime_ns();
+ entry->tokens = TOKEN_MAX - PACKET_COST;
+ spin_lock(&table_lock);
+ hlist_add_head_rcu(&entry->hash, bucket);
+ spin_unlock(&table_lock);
+ return true;
+
+err_oom:
+ atomic_dec(&total_entries);
+ return false;
+}
+
+int wg_ratelimiter_init(void)
+{
+ mutex_lock(&init_lock);
+ if (++init_refcnt != 1)
+ goto out;
+
+ entry_cache = KMEM_CACHE(ratelimiter_entry, 0);
+ if (!entry_cache)
+ goto err;
+
+ /* xt_hashlimit.c uses a slightly different algorithm for ratelimiting,
+ * but what it shares in common is that it uses a massive hashtable. So,
+ * we borrow their wisdom about good table sizes on different systems
+ * dependent on RAM. This calculation here comes from there.
+ */
+ table_size = (totalram_pages() > (1U << 30) / PAGE_SIZE) ? 8192 :
+ max_t(unsigned long, 16, roundup_pow_of_two(
+ (totalram_pages() << PAGE_SHIFT) /
+ (1U << 14) / sizeof(struct hlist_head)));
+ max_entries = table_size * 8;
+
+ table_v4 = kvcalloc(table_size, sizeof(*table_v4), GFP_KERNEL);
+ if (unlikely(!table_v4))
+ goto err_kmemcache;
+
+#if IS_ENABLED(CONFIG_IPV6)
+ table_v6 = kvcalloc(table_size, sizeof(*table_v6), GFP_KERNEL);
+ if (unlikely(!table_v6)) {
+ kvfree(table_v4);
+ goto err_kmemcache;
+ }
+#endif
+
+ queue_delayed_work(system_power_efficient_wq, &gc_work, HZ);
+ get_random_bytes(&key, sizeof(key));
+out:
+ mutex_unlock(&init_lock);
+ return 0;
+
+err_kmemcache:
+ kmem_cache_destroy(entry_cache);
+err:
+ --init_refcnt;
+ mutex_unlock(&init_lock);
+ return -ENOMEM;
+}
+
+void wg_ratelimiter_uninit(void)
+{
+ mutex_lock(&init_lock);
+ if (!init_refcnt || --init_refcnt)
+ goto out;
+
+ cancel_delayed_work_sync(&gc_work);
+ wg_ratelimiter_gc_entries(NULL);
+ rcu_barrier();
+ kvfree(table_v4);
+#if IS_ENABLED(CONFIG_IPV6)
+ kvfree(table_v6);
+#endif
+ kmem_cache_destroy(entry_cache);
+out:
+ mutex_unlock(&init_lock);
+}
+
+#include "selftest/ratelimiter.c"