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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
commit4352b8aee98005853aa63f57d6377282de17a33f (patch)
tree27614d7a9ef05c32d089004e104364ce42324837 /drivers/net/wireguard/allowedips.c
downloadlinux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz
linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ...
Diffstat (limited to 'drivers/net/wireguard/allowedips.c')
-rw-r--r--drivers/net/wireguard/allowedips.c424
1 files changed, 424 insertions, 0 deletions
diff --git a/drivers/net/wireguard/allowedips.c b/drivers/net/wireguard/allowedips.c
new file mode 100644
index 000000000..5ece9acad
--- /dev/null
+++ b/drivers/net/wireguard/allowedips.c
@@ -0,0 +1,424 @@
+// 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_DEPTH = 129 };
+
+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] = get_unaligned_be64(src);
+ ((u64 *)dst)[1] = get_unaligned_be64(src + 8);
+ }
+}
+
+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_DEPTH))
+ return;
+ stack[(*len)++] = rcu_dereference_raw(p);
+ }
+}
+
+static void root_free_rcu(struct rcu_head *rcu)
+{
+ struct allowedips_node *node, *stack[MAX_ALLOWEDIPS_DEPTH] = {
+ 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_DEPTH] = { 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;
+}
+
+static void remove_node(struct allowedips_node *node, struct mutex *lock)
+{
+ struct allowedips_node *child, **parent_bit, *parent;
+ bool free_parent;
+
+ list_del_init(&node->peer_list);
+ RCU_INIT_POINTER(node->peer, NULL);
+ if (node->bit[0] && node->bit[1])
+ return;
+ 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));
+ kfree_rcu(node, rcu);
+ if (!free_parent)
+ return;
+ if (child)
+ child->parent_bit_packed = parent->parent_bit_packed;
+ *(struct allowedips_node **)(parent->parent_bit_packed & ~3UL) = child;
+ kfree_rcu(parent, rcu);
+}
+
+static int remove(struct allowedips_node __rcu **trie, u8 bits, const u8 *key,
+ u8 cidr, struct wg_peer *peer, struct mutex *lock)
+{
+ struct allowedips_node *node;
+
+ if (unlikely(cidr > bits))
+ return -EINVAL;
+ if (!rcu_access_pointer(*trie) || !node_placement(*trie, key, cidr, bits, &node, lock) ||
+ peer != rcu_access_pointer(node->peer))
+ return 0;
+
+ remove_node(node, lock);
+ 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);
+}
+
+int wg_allowedips_remove_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 remove(&table->root4, 32, key, cidr, peer, lock);
+}
+
+int wg_allowedips_remove_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 remove(&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, *tmp;
+
+ if (list_empty(&peer->allowedips_list))
+ return;
+ ++table->seq;
+ list_for_each_entry_safe(node, tmp, &peer->allowedips_list, peer_list)
+ remove_node(node, lock);
+}
+
+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"