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().
  ...

1 files changed, 389 insertions, 0 deletions

diff --git a/drivers/net/wireguard/allowedips.c b/drivers/net/wireguard/allowedips.c
new file mode 100644
index 000000000..5bf7822c5
--- /dev/null
+++ b/drivers/net/wireguard/allowedips.c
@@ -0,0 +1,389 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+
+#include "allowedips.h"
+#include "peer.h"
+
+enum { MAX_ALLOWEDIPS_BITS = 128 };
+
+static struct kmem_cache *node_cache;
+
+static void swap_endian(u8 *dst, const u8 *src, u8 bits)
+{
+	if (bits == 32) {
+		*(u32 *)dst = be32_to_cpu(*(const __be32 *)src);
+	} else if (bits == 128) {
+		((u64 *)dst)[0] = be64_to_cpu(((const __be64 *)src)[0]);
+		((u64 *)dst)[1] = be64_to_cpu(((const __be64 *)src)[1]);
+	}
+}
+
+static void copy_and_assign_cidr(struct allowedips_node *node, const u8 *src,
+				 u8 cidr, u8 bits)
+{
+	node->cidr = cidr;
+	node->bit_at_a = cidr / 8U;
+#ifdef __LITTLE_ENDIAN
+	node->bit_at_a ^= (bits / 8U - 1U) % 8U;
+#endif
+	node->bit_at_b = 7U - (cidr % 8U);
+	node->bitlen = bits;
+	memcpy(node->bits, src, bits / 8U);
+}
+
+static inline u8 choose(struct allowedips_node *node, const u8 *key)
+{
+	return (key[node->bit_at_a] >> node->bit_at_b) & 1;
+}
+
+static void push_rcu(struct allowedips_node **stack,
+		     struct allowedips_node __rcu *p, unsigned int *len)
+{
+	if (rcu_access_pointer(p)) {
+		if (WARN_ON(IS_ENABLED(DEBUG) && *len >= MAX_ALLOWEDIPS_BITS))
+			return;
+		stack[(*len)++] = rcu_dereference_raw(p);
+	}
+}
+
+static void node_free_rcu(struct rcu_head *rcu)
+{
+	kmem_cache_free(node_cache, container_of(rcu, struct allowedips_node, rcu));
+}
+
+static void root_free_rcu(struct rcu_head *rcu)
+{
+	struct allowedips_node *node, *stack[MAX_ALLOWEDIPS_BITS] = {
+		container_of(rcu, struct allowedips_node, rcu) };
+	unsigned int len = 1;
+
+	while (len > 0 && (node = stack[--len])) {
+		push_rcu(stack, node->bit[0], &len);
+		push_rcu(stack, node->bit[1], &len);
+		kmem_cache_free(node_cache, node);
+	}
+}
+
+static void root_remove_peer_lists(struct allowedips_node *root)
+{
+	struct allowedips_node *node, *stack[MAX_ALLOWEDIPS_BITS] = { root };
+	unsigned int len = 1;
+
+	while (len > 0 && (node = stack[--len])) {
+		push_rcu(stack, node->bit[0], &len);
+		push_rcu(stack, node->bit[1], &len);
+		if (rcu_access_pointer(node->peer))
+			list_del(&node->peer_list);
+	}
+}
+
+static unsigned int fls128(u64 a, u64 b)
+{
+	return a ? fls64(a) + 64U : fls64(b);
+}
+
+static u8 common_bits(const struct allowedips_node *node, const u8 *key,
+		      u8 bits)
+{
+	if (bits == 32)
+		return 32U - fls(*(const u32 *)node->bits ^ *(const u32 *)key);
+	else if (bits == 128)
+		return 128U - fls128(
+			*(const u64 *)&node->bits[0] ^ *(const u64 *)&key[0],
+			*(const u64 *)&node->bits[8] ^ *(const u64 *)&key[8]);
+	return 0;
+}
+
+static bool prefix_matches(const struct allowedips_node *node, const u8 *key,
+			   u8 bits)
+{
+	/* This could be much faster if it actually just compared the common
+	 * bits properly, by precomputing a mask bswap(~0 << (32 - cidr)), and
+	 * the rest, but it turns out that common_bits is already super fast on
+	 * modern processors, even taking into account the unfortunate bswap.
+	 * So, we just inline it like this instead.
+	 */
+	return common_bits(node, key, bits) >= node->cidr;
+}
+
+static struct allowedips_node *find_node(struct allowedips_node *trie, u8 bits,
+					 const u8 *key)
+{
+	struct allowedips_node *node = trie, *found = NULL;
+
+	while (node && prefix_matches(node, key, bits)) {
+		if (rcu_access_pointer(node->peer))
+			found = node;
+		if (node->cidr == bits)
+			break;
+		node = rcu_dereference_bh(node->bit[choose(node, key)]);
+	}
+	return found;
+}
+
+/* Returns a strong reference to a peer */
+static struct wg_peer *lookup(struct allowedips_node __rcu *root, u8 bits,
+			      const void *be_ip)
+{
+	/* Aligned so it can be passed to fls/fls64 */
+	u8 ip[16] __aligned(__alignof(u64));
+	struct allowedips_node *node;
+	struct wg_peer *peer = NULL;
+
+	swap_endian(ip, be_ip, bits);
+
+	rcu_read_lock_bh();
+retry:
+	node = find_node(rcu_dereference_bh(root), bits, ip);
+	if (node) {
+		peer = wg_peer_get_maybe_zero(rcu_dereference_bh(node->peer));
+		if (!peer)
+			goto retry;
+	}
+	rcu_read_unlock_bh();
+	return peer;
+}
+
+static bool node_placement(struct allowedips_node __rcu *trie, const u8 *key,
+			   u8 cidr, u8 bits, struct allowedips_node **rnode,
+			   struct mutex *lock)
+{
+	struct allowedips_node *node = rcu_dereference_protected(trie, lockdep_is_held(lock));
+	struct allowedips_node *parent = NULL;
+	bool exact = false;
+
+	while (node && node->cidr <= cidr && prefix_matches(node, key, bits)) {
+		parent = node;
+		if (parent->cidr == cidr) {
+			exact = true;
+			break;
+		}
+		node = rcu_dereference_protected(parent->bit[choose(parent, key)], lockdep_is_held(lock));
+	}
+	*rnode = parent;
+	return exact;
+}
+
+static inline void connect_node(struct allowedips_node __rcu **parent, u8 bit, struct allowedips_node *node)
+{
+	node->parent_bit_packed = (unsigned long)parent | bit;
+	rcu_assign_pointer(*parent, node);
+}
+
+static inline void choose_and_connect_node(struct allowedips_node *parent, struct allowedips_node *node)
+{
+	u8 bit = choose(parent, node->bits);
+	connect_node(&parent->bit[bit], bit, node);
+}
+
+static int add(struct allowedips_node __rcu **trie, u8 bits, const u8 *key,
+	       u8 cidr, struct wg_peer *peer, struct mutex *lock)
+{
+	struct allowedips_node *node, *parent, *down, *newnode;
+
+	if (unlikely(cidr > bits || !peer))
+		return -EINVAL;
+
+	if (!rcu_access_pointer(*trie)) {
+		node = kmem_cache_zalloc(node_cache, GFP_KERNEL);
+		if (unlikely(!node))
+			return -ENOMEM;
+		RCU_INIT_POINTER(node->peer, peer);
+		list_add_tail(&node->peer_list, &peer->allowedips_list);
+		copy_and_assign_cidr(node, key, cidr, bits);
+		connect_node(trie, 2, node);
+		return 0;
+	}
+	if (node_placement(*trie, key, cidr, bits, &node, lock)) {
+		rcu_assign_pointer(node->peer, peer);
+		list_move_tail(&node->peer_list, &peer->allowedips_list);
+		return 0;
+	}
+
+	newnode = kmem_cache_zalloc(node_cache, GFP_KERNEL);
+	if (unlikely(!newnode))
+		return -ENOMEM;
+	RCU_INIT_POINTER(newnode->peer, peer);
+	list_add_tail(&newnode->peer_list, &peer->allowedips_list);
+	copy_and_assign_cidr(newnode, key, cidr, bits);
+
+	if (!node) {
+		down = rcu_dereference_protected(*trie, lockdep_is_held(lock));
+	} else {
+		const u8 bit = choose(node, key);
+		down = rcu_dereference_protected(node->bit[bit], lockdep_is_held(lock));
+		if (!down) {
+			connect_node(&node->bit[bit], bit, newnode);
+			return 0;
+		}
+	}
+	cidr = min(cidr, common_bits(down, key, bits));
+	parent = node;
+
+	if (newnode->cidr == cidr) {
+		choose_and_connect_node(newnode, down);
+		if (!parent)
+			connect_node(trie, 2, newnode);
+		else
+			choose_and_connect_node(parent, newnode);
+		return 0;
+	}
+
+	node = kmem_cache_zalloc(node_cache, GFP_KERNEL);
+	if (unlikely(!node)) {
+		list_del(&newnode->peer_list);
+		kmem_cache_free(node_cache, newnode);
+		return -ENOMEM;
+	}
+	INIT_LIST_HEAD(&node->peer_list);
+	copy_and_assign_cidr(node, newnode->bits, cidr, bits);
+
+	choose_and_connect_node(node, down);
+	choose_and_connect_node(node, newnode);
+	if (!parent)
+		connect_node(trie, 2, node);
+	else
+		choose_and_connect_node(parent, node);
+	return 0;
+}
+
+void wg_allowedips_init(struct allowedips *table)
+{
+	table->root4 = table->root6 = NULL;
+	table->seq = 1;
+}
+
+void wg_allowedips_free(struct allowedips *table, struct mutex *lock)
+{
+	struct allowedips_node __rcu *old4 = table->root4, *old6 = table->root6;
+
+	++table->seq;
+	RCU_INIT_POINTER(table->root4, NULL);
+	RCU_INIT_POINTER(table->root6, NULL);
+	if (rcu_access_pointer(old4)) {
+		struct allowedips_node *node = rcu_dereference_protected(old4,
+							lockdep_is_held(lock));
+
+		root_remove_peer_lists(node);
+		call_rcu(&node->rcu, root_free_rcu);
+	}
+	if (rcu_access_pointer(old6)) {
+		struct allowedips_node *node = rcu_dereference_protected(old6,
+							lockdep_is_held(lock));
+
+		root_remove_peer_lists(node);
+		call_rcu(&node->rcu, root_free_rcu);
+	}
+}
+
+int wg_allowedips_insert_v4(struct allowedips *table, const struct in_addr *ip,
+			    u8 cidr, struct wg_peer *peer, struct mutex *lock)
+{
+	/* Aligned so it can be passed to fls */
+	u8 key[4] __aligned(__alignof(u32));
+
+	++table->seq;
+	swap_endian(key, (const u8 *)ip, 32);
+	return add(&table->root4, 32, key, cidr, peer, lock);
+}
+
+int wg_allowedips_insert_v6(struct allowedips *table, const struct in6_addr *ip,
+			    u8 cidr, struct wg_peer *peer, struct mutex *lock)
+{
+	/* Aligned so it can be passed to fls64 */
+	u8 key[16] __aligned(__alignof(u64));
+
+	++table->seq;
+	swap_endian(key, (const u8 *)ip, 128);
+	return add(&table->root6, 128, key, cidr, peer, lock);
+}
+
+void wg_allowedips_remove_by_peer(struct allowedips *table,
+				  struct wg_peer *peer, struct mutex *lock)
+{
+	struct allowedips_node *node, *child, **parent_bit, *parent, *tmp;
+	bool free_parent;
+
+	if (list_empty(&peer->allowedips_list))
+		return;
+	++table->seq;
+	list_for_each_entry_safe(node, tmp, &peer->allowedips_list, peer_list) {
+		list_del_init(&node->peer_list);
+		RCU_INIT_POINTER(node->peer, NULL);
+		if (node->bit[0] && node->bit[1])
+			continue;
+		child = rcu_dereference_protected(node->bit[!rcu_access_pointer(node->bit[0])],
+						  lockdep_is_held(lock));
+		if (child)
+			child->parent_bit_packed = node->parent_bit_packed;
+		parent_bit = (struct allowedips_node **)(node->parent_bit_packed & ~3UL);
+		*parent_bit = child;
+		parent = (void *)parent_bit -
+			 offsetof(struct allowedips_node, bit[node->parent_bit_packed & 1]);
+		free_parent = !rcu_access_pointer(node->bit[0]) &&
+			      !rcu_access_pointer(node->bit[1]) &&
+			      (node->parent_bit_packed & 3) <= 1 &&
+			      !rcu_access_pointer(parent->peer);
+		if (free_parent)
+			child = rcu_dereference_protected(
+					parent->bit[!(node->parent_bit_packed & 1)],
+					lockdep_is_held(lock));
+		call_rcu(&node->rcu, node_free_rcu);
+		if (!free_parent)
+			continue;
+		if (child)
+			child->parent_bit_packed = parent->parent_bit_packed;
+		*(struct allowedips_node **)(parent->parent_bit_packed & ~3UL) = child;
+		call_rcu(&parent->rcu, node_free_rcu);
+	}
+}
+
+int wg_allowedips_read_node(struct allowedips_node *node, u8 ip[16], u8 *cidr)
+{
+	const unsigned int cidr_bytes = DIV_ROUND_UP(node->cidr, 8U);
+	swap_endian(ip, node->bits, node->bitlen);
+	memset(ip + cidr_bytes, 0, node->bitlen / 8U - cidr_bytes);
+	if (node->cidr)
+		ip[cidr_bytes - 1U] &= ~0U << (-node->cidr % 8U);
+
+	*cidr = node->cidr;
+	return node->bitlen == 32 ? AF_INET : AF_INET6;
+}
+
+/* Returns a strong reference to a peer */
+struct wg_peer *wg_allowedips_lookup_dst(struct allowedips *table,
+					 struct sk_buff *skb)
+{
+	if (skb->protocol == htons(ETH_P_IP))
+		return lookup(table->root4, 32, &ip_hdr(skb)->daddr);
+	else if (skb->protocol == htons(ETH_P_IPV6))
+		return lookup(table->root6, 128, &ipv6_hdr(skb)->daddr);
+	return NULL;
+}
+
+/* Returns a strong reference to a peer */
+struct wg_peer *wg_allowedips_lookup_src(struct allowedips *table,
+					 struct sk_buff *skb)
+{
+	if (skb->protocol == htons(ETH_P_IP))
+		return lookup(table->root4, 32, &ip_hdr(skb)->saddr);
+	else if (skb->protocol == htons(ETH_P_IPV6))
+		return lookup(table->root6, 128, &ipv6_hdr(skb)->saddr);
+	return NULL;
+}
+
+int __init wg_allowedips_slab_init(void)
+{
+	node_cache = KMEM_CACHE(allowedips_node, 0);
+	return node_cache ? 0 : -ENOMEM;
+}
+
+void wg_allowedips_slab_uninit(void)
+{
+	rcu_barrier();
+	kmem_cache_destroy(node_cache);
+}
+
+#include "selftest/allowedips.c"