Update Linux to v5.10.109
Sourced from [1]
[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.10.109.tar.xz
Change-Id: I19bca9fc6762d4e63bcf3e4cba88bbe560d9c76c
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/drivers/net/wireguard/peerlookup.c b/drivers/net/wireguard/peerlookup.c
new file mode 100644
index 0000000..f2783aa
--- /dev/null
+++ b/drivers/net/wireguard/peerlookup.c
@@ -0,0 +1,226 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+
+#include "peerlookup.h"
+#include "peer.h"
+#include "noise.h"
+
+static struct hlist_head *pubkey_bucket(struct pubkey_hashtable *table,
+ const u8 pubkey[NOISE_PUBLIC_KEY_LEN])
+{
+ /* siphash gives us a secure 64bit number based on a random key. Since
+ * the bits are uniformly distributed, we can then mask off to get the
+ * bits we need.
+ */
+ const u64 hash = siphash(pubkey, NOISE_PUBLIC_KEY_LEN, &table->key);
+
+ return &table->hashtable[hash & (HASH_SIZE(table->hashtable) - 1)];
+}
+
+struct pubkey_hashtable *wg_pubkey_hashtable_alloc(void)
+{
+ struct pubkey_hashtable *table = kvmalloc(sizeof(*table), GFP_KERNEL);
+
+ if (!table)
+ return NULL;
+
+ get_random_bytes(&table->key, sizeof(table->key));
+ hash_init(table->hashtable);
+ mutex_init(&table->lock);
+ return table;
+}
+
+void wg_pubkey_hashtable_add(struct pubkey_hashtable *table,
+ struct wg_peer *peer)
+{
+ mutex_lock(&table->lock);
+ hlist_add_head_rcu(&peer->pubkey_hash,
+ pubkey_bucket(table, peer->handshake.remote_static));
+ mutex_unlock(&table->lock);
+}
+
+void wg_pubkey_hashtable_remove(struct pubkey_hashtable *table,
+ struct wg_peer *peer)
+{
+ mutex_lock(&table->lock);
+ hlist_del_init_rcu(&peer->pubkey_hash);
+ mutex_unlock(&table->lock);
+}
+
+/* Returns a strong reference to a peer */
+struct wg_peer *
+wg_pubkey_hashtable_lookup(struct pubkey_hashtable *table,
+ const u8 pubkey[NOISE_PUBLIC_KEY_LEN])
+{
+ struct wg_peer *iter_peer, *peer = NULL;
+
+ rcu_read_lock_bh();
+ hlist_for_each_entry_rcu_bh(iter_peer, pubkey_bucket(table, pubkey),
+ pubkey_hash) {
+ if (!memcmp(pubkey, iter_peer->handshake.remote_static,
+ NOISE_PUBLIC_KEY_LEN)) {
+ peer = iter_peer;
+ break;
+ }
+ }
+ peer = wg_peer_get_maybe_zero(peer);
+ rcu_read_unlock_bh();
+ return peer;
+}
+
+static struct hlist_head *index_bucket(struct index_hashtable *table,
+ const __le32 index)
+{
+ /* Since the indices are random and thus all bits are uniformly
+ * distributed, we can find its bucket simply by masking.
+ */
+ return &table->hashtable[(__force u32)index &
+ (HASH_SIZE(table->hashtable) - 1)];
+}
+
+struct index_hashtable *wg_index_hashtable_alloc(void)
+{
+ struct index_hashtable *table = kvmalloc(sizeof(*table), GFP_KERNEL);
+
+ if (!table)
+ return NULL;
+
+ hash_init(table->hashtable);
+ spin_lock_init(&table->lock);
+ return table;
+}
+
+/* At the moment, we limit ourselves to 2^20 total peers, which generally might
+ * amount to 2^20*3 items in this hashtable. The algorithm below works by
+ * picking a random number and testing it. We can see that these limits mean we
+ * usually succeed pretty quickly:
+ *
+ * >>> def calculation(tries, size):
+ * ... return (size / 2**32)**(tries - 1) * (1 - (size / 2**32))
+ * ...
+ * >>> calculation(1, 2**20 * 3)
+ * 0.999267578125
+ * >>> calculation(2, 2**20 * 3)
+ * 0.0007318854331970215
+ * >>> calculation(3, 2**20 * 3)
+ * 5.360489012673497e-07
+ * >>> calculation(4, 2**20 * 3)
+ * 3.9261394135792216e-10
+ *
+ * At the moment, we don't do any masking, so this algorithm isn't exactly
+ * constant time in either the random guessing or in the hash list lookup. We
+ * could require a minimum of 3 tries, which would successfully mask the
+ * guessing. this would not, however, help with the growing hash lengths, which
+ * is another thing to consider moving forward.
+ */
+
+__le32 wg_index_hashtable_insert(struct index_hashtable *table,
+ struct index_hashtable_entry *entry)
+{
+ struct index_hashtable_entry *existing_entry;
+
+ spin_lock_bh(&table->lock);
+ hlist_del_init_rcu(&entry->index_hash);
+ spin_unlock_bh(&table->lock);
+
+ rcu_read_lock_bh();
+
+search_unused_slot:
+ /* First we try to find an unused slot, randomly, while unlocked. */
+ entry->index = (__force __le32)get_random_u32();
+ hlist_for_each_entry_rcu_bh(existing_entry,
+ index_bucket(table, entry->index),
+ index_hash) {
+ if (existing_entry->index == entry->index)
+ /* If it's already in use, we continue searching. */
+ goto search_unused_slot;
+ }
+
+ /* Once we've found an unused slot, we lock it, and then double-check
+ * that nobody else stole it from us.
+ */
+ spin_lock_bh(&table->lock);
+ hlist_for_each_entry_rcu_bh(existing_entry,
+ index_bucket(table, entry->index),
+ index_hash) {
+ if (existing_entry->index == entry->index) {
+ spin_unlock_bh(&table->lock);
+ /* If it was stolen, we start over. */
+ goto search_unused_slot;
+ }
+ }
+ /* Otherwise, we know we have it exclusively (since we're locked),
+ * so we insert.
+ */
+ hlist_add_head_rcu(&entry->index_hash,
+ index_bucket(table, entry->index));
+ spin_unlock_bh(&table->lock);
+
+ rcu_read_unlock_bh();
+
+ return entry->index;
+}
+
+bool wg_index_hashtable_replace(struct index_hashtable *table,
+ struct index_hashtable_entry *old,
+ struct index_hashtable_entry *new)
+{
+ bool ret;
+
+ spin_lock_bh(&table->lock);
+ ret = !hlist_unhashed(&old->index_hash);
+ if (unlikely(!ret))
+ goto out;
+
+ new->index = old->index;
+ hlist_replace_rcu(&old->index_hash, &new->index_hash);
+
+ /* Calling init here NULLs out index_hash, and in fact after this
+ * function returns, it's theoretically possible for this to get
+ * reinserted elsewhere. That means the RCU lookup below might either
+ * terminate early or jump between buckets, in which case the packet
+ * simply gets dropped, which isn't terrible.
+ */
+ INIT_HLIST_NODE(&old->index_hash);
+out:
+ spin_unlock_bh(&table->lock);
+ return ret;
+}
+
+void wg_index_hashtable_remove(struct index_hashtable *table,
+ struct index_hashtable_entry *entry)
+{
+ spin_lock_bh(&table->lock);
+ hlist_del_init_rcu(&entry->index_hash);
+ spin_unlock_bh(&table->lock);
+}
+
+/* Returns a strong reference to a entry->peer */
+struct index_hashtable_entry *
+wg_index_hashtable_lookup(struct index_hashtable *table,
+ const enum index_hashtable_type type_mask,
+ const __le32 index, struct wg_peer **peer)
+{
+ struct index_hashtable_entry *iter_entry, *entry = NULL;
+
+ rcu_read_lock_bh();
+ hlist_for_each_entry_rcu_bh(iter_entry, index_bucket(table, index),
+ index_hash) {
+ if (iter_entry->index == index) {
+ if (likely(iter_entry->type & type_mask))
+ entry = iter_entry;
+ break;
+ }
+ }
+ if (likely(entry)) {
+ entry->peer = wg_peer_get_maybe_zero(entry->peer);
+ if (likely(entry->peer))
+ *peer = entry->peer;
+ else
+ entry = NULL;
+ }
+ rcu_read_unlock_bh();
+ return entry;
+}