Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next

Pull networking updates from David Miller:
 "Another merge window, another pull full of stuff:

   1) Support alternative names for network devices, from Jiri Pirko.

   2) Introduce per-netns netdev notifiers, also from Jiri Pirko.

   3) Support MSG_PEEK in vsock/virtio, from Matias Ezequiel Vara
      Larsen.

   4) Allow compiling out the TLS TOE code, from Jakub Kicinski.

   5) Add several new tracepoints to the kTLS code, also from Jakub.

   6) Support set channels ethtool callback in ena driver, from Sameeh
      Jubran.

   7) New SCTP events SCTP_ADDR_ADDED, SCTP_ADDR_REMOVED,
      SCTP_ADDR_MADE_PRIM, and SCTP_SEND_FAILED_EVENT. From Xin Long.

   8) Add XDP support to mvneta driver, from Lorenzo Bianconi.

   9) Lots of netfilter hw offload fixes, cleanups and enhancements,
      from Pablo Neira Ayuso.

  10) PTP support for aquantia chips, from Egor Pomozov.

  11) Add UDP segmentation offload support to igb, ixgbe, and i40e. From
      Josh Hunt.

  12) Add smart nagle to tipc, from Jon Maloy.

  13) Support L2 field rewrite by TC offloads in bnxt_en, from Venkat
      Duvvuru.

  14) Add a flow mask cache to OVS, from Tonghao Zhang.

  15) Add XDP support to ice driver, from Maciej Fijalkowski.

  16) Add AF_XDP support to ice driver, from Krzysztof Kazimierczak.

  17) Support UDP GSO offload in atlantic driver, from Igor Russkikh.

  18) Support it in stmmac driver too, from Jose Abreu.

  19) Support TIPC encryption and auth, from Tuong Lien.

  20) Introduce BPF trampolines, from Alexei Starovoitov.

  21) Make page_pool API more numa friendly, from Saeed Mahameed.

  22) Introduce route hints to ipv4 and ipv6, from Paolo Abeni.

  23) Add UDP segmentation offload to cxgb4, Rahul Lakkireddy"

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1857 commits)
  libbpf: Fix usage of u32 in userspace code
  mm: Implement no-MMU variant of vmalloc_user_node_flags
  slip: Fix use-after-free Read in slip_open
  net: dsa: sja1105: fix sja1105_parse_rgmii_delays()
  macvlan: schedule bc_work even if error
  enetc: add support Credit Based Shaper(CBS) for hardware offload
  net: phy: add helpers phy_(un)lock_mdio_bus
  mdio_bus: don't use managed reset-controller
  ax88179_178a: add ethtool_op_get_ts_info()
  mlxsw: spectrum_router: Fix use of uninitialized adjacency index
  mlxsw: spectrum_router: After underlay moves, demote conflicting tunnels
  bpf: Simplify __bpf_arch_text_poke poke type handling
  bpf: Introduce BPF_TRACE_x helper for the tracing tests
  bpf: Add bpf_jit_blinding_enabled for !CONFIG_BPF_JIT
  bpf, testing: Add various tail call test cases
  bpf, x86: Emit patchable direct jump as tail call
  bpf: Constant map key tracking for prog array pokes
  bpf: Add poke dependency tracking for prog array maps
  bpf: Add initial poke descriptor table for jit images
  bpf: Move owner type, jited info into array auxiliary data
  ...

1 files changed, 1986 insertions, 0 deletions

diff --git a/net/tipc/crypto.c b/net/tipc/crypto.c
new file mode 100644
index 000000000000..990a872cec46
--- /dev/null
+++ b/net/tipc/crypto.c
@@ -0,0 +1,1986 @@
+// SPDX-License-Identifier: GPL-2.0
+/**
+ * net/tipc/crypto.c: TIPC crypto for key handling & packet en/decryption
+ *
+ * Copyright (c) 2019, Ericsson AB
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the names of the copyright holders nor the names of its
+ *    contributors may be used to endorse or promote products derived from
+ *    this software without specific prior written permission.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") version 2 as published by the Free
+ * Software Foundation.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <crypto/aead.h>
+#include <crypto/aes.h>
+#include "crypto.h"
+
+#define TIPC_TX_PROBE_LIM	msecs_to_jiffies(1000) /* > 1s */
+#define TIPC_TX_LASTING_LIM	msecs_to_jiffies(120000) /* 2 mins */
+#define TIPC_RX_ACTIVE_LIM	msecs_to_jiffies(3000) /* 3s */
+#define TIPC_RX_PASSIVE_LIM	msecs_to_jiffies(180000) /* 3 mins */
+#define TIPC_MAX_TFMS_DEF	10
+#define TIPC_MAX_TFMS_LIM	1000
+
+/**
+ * TIPC Key ids
+ */
+enum {
+	KEY_UNUSED = 0,
+	KEY_MIN,
+	KEY_1 = KEY_MIN,
+	KEY_2,
+	KEY_3,
+	KEY_MAX = KEY_3,
+};
+
+/**
+ * TIPC Crypto statistics
+ */
+enum {
+	STAT_OK,
+	STAT_NOK,
+	STAT_ASYNC,
+	STAT_ASYNC_OK,
+	STAT_ASYNC_NOK,
+	STAT_BADKEYS, /* tx only */
+	STAT_BADMSGS = STAT_BADKEYS, /* rx only */
+	STAT_NOKEYS,
+	STAT_SWITCHES,
+
+	MAX_STATS,
+};
+
+/* TIPC crypto statistics' header */
+static const char *hstats[MAX_STATS] = {"ok", "nok", "async", "async_ok",
+					"async_nok", "badmsgs", "nokeys",
+					"switches"};
+
+/* Max TFMs number per key */
+int sysctl_tipc_max_tfms __read_mostly = TIPC_MAX_TFMS_DEF;
+
+/**
+ * struct tipc_key - TIPC keys' status indicator
+ *
+ *         7     6     5     4     3     2     1     0
+ *      +-----+-----+-----+-----+-----+-----+-----+-----+
+ * key: | (reserved)|passive idx| active idx|pending idx|
+ *      +-----+-----+-----+-----+-----+-----+-----+-----+
+ */
+struct tipc_key {
+#define KEY_BITS (2)
+#define KEY_MASK ((1 << KEY_BITS) - 1)
+	union {
+		struct {
+#if defined(__LITTLE_ENDIAN_BITFIELD)
+			u8 pending:2,
+			   active:2,
+			   passive:2, /* rx only */
+			   reserved:2;
+#elif defined(__BIG_ENDIAN_BITFIELD)
+			u8 reserved:2,
+			   passive:2, /* rx only */
+			   active:2,
+			   pending:2;
+#else
+#error  "Please fix <asm/byteorder.h>"
+#endif
+		} __packed;
+		u8 keys;
+	};
+};
+
+/**
+ * struct tipc_tfm - TIPC TFM structure to form a list of TFMs
+ */
+struct tipc_tfm {
+	struct crypto_aead *tfm;
+	struct list_head list;
+};
+
+/**
+ * struct tipc_aead - TIPC AEAD key structure
+ * @tfm_entry: per-cpu pointer to one entry in TFM list
+ * @crypto: TIPC crypto owns this key
+ * @cloned: reference to the source key in case cloning
+ * @users: the number of the key users (TX/RX)
+ * @salt: the key's SALT value
+ * @authsize: authentication tag size (max = 16)
+ * @mode: crypto mode is applied to the key
+ * @hint[]: a hint for user key
+ * @rcu: struct rcu_head
+ * @seqno: the key seqno (cluster scope)
+ * @refcnt: the key reference counter
+ */
+struct tipc_aead {
+#define TIPC_AEAD_HINT_LEN (5)
+	struct tipc_tfm * __percpu *tfm_entry;
+	struct tipc_crypto *crypto;
+	struct tipc_aead *cloned;
+	atomic_t users;
+	u32 salt;
+	u8 authsize;
+	u8 mode;
+	char hint[TIPC_AEAD_HINT_LEN + 1];
+	struct rcu_head rcu;
+
+	atomic64_t seqno ____cacheline_aligned;
+	refcount_t refcnt ____cacheline_aligned;
+
+} ____cacheline_aligned;
+
+/**
+ * struct tipc_crypto_stats - TIPC Crypto statistics
+ */
+struct tipc_crypto_stats {
+	unsigned int stat[MAX_STATS];
+};
+
+/**
+ * struct tipc_crypto - TIPC TX/RX crypto structure
+ * @net: struct net
+ * @node: TIPC node (RX)
+ * @aead: array of pointers to AEAD keys for encryption/decryption
+ * @peer_rx_active: replicated peer RX active key index
+ * @key: the key states
+ * @working: the crypto is working or not
+ * @stats: the crypto statistics
+ * @sndnxt: the per-peer sndnxt (TX)
+ * @timer1: general timer 1 (jiffies)
+ * @timer2: general timer 1 (jiffies)
+ * @lock: tipc_key lock
+ */
+struct tipc_crypto {
+	struct net *net;
+	struct tipc_node *node;
+	struct tipc_aead __rcu *aead[KEY_MAX + 1]; /* key[0] is UNUSED */
+	atomic_t peer_rx_active;
+	struct tipc_key key;
+	u8 working:1;
+	struct tipc_crypto_stats __percpu *stats;
+
+	atomic64_t sndnxt ____cacheline_aligned;
+	unsigned long timer1;
+	unsigned long timer2;
+	spinlock_t lock; /* crypto lock */
+
+} ____cacheline_aligned;
+
+/* struct tipc_crypto_tx_ctx - TX context for callbacks */
+struct tipc_crypto_tx_ctx {
+	struct tipc_aead *aead;
+	struct tipc_bearer *bearer;
+	struct tipc_media_addr dst;
+};
+
+/* struct tipc_crypto_rx_ctx - RX context for callbacks */
+struct tipc_crypto_rx_ctx {
+	struct tipc_aead *aead;
+	struct tipc_bearer *bearer;
+};
+
+static struct tipc_aead *tipc_aead_get(struct tipc_aead __rcu *aead);
+static inline void tipc_aead_put(struct tipc_aead *aead);
+static void tipc_aead_free(struct rcu_head *rp);
+static int tipc_aead_users(struct tipc_aead __rcu *aead);
+static void tipc_aead_users_inc(struct tipc_aead __rcu *aead, int lim);
+static void tipc_aead_users_dec(struct tipc_aead __rcu *aead, int lim);
+static void tipc_aead_users_set(struct tipc_aead __rcu *aead, int val);
+static struct crypto_aead *tipc_aead_tfm_next(struct tipc_aead *aead);
+static int tipc_aead_init(struct tipc_aead **aead, struct tipc_aead_key *ukey,
+			  u8 mode);
+static int tipc_aead_clone(struct tipc_aead **dst, struct tipc_aead *src);
+static void *tipc_aead_mem_alloc(struct crypto_aead *tfm,
+				 unsigned int crypto_ctx_size,
+				 u8 **iv, struct aead_request **req,
+				 struct scatterlist **sg, int nsg);
+static int tipc_aead_encrypt(struct tipc_aead *aead, struct sk_buff *skb,
+			     struct tipc_bearer *b,
+			     struct tipc_media_addr *dst,
+			     struct tipc_node *__dnode);
+static void tipc_aead_encrypt_done(struct crypto_async_request *base, int err);
+static int tipc_aead_decrypt(struct net *net, struct tipc_aead *aead,
+			     struct sk_buff *skb, struct tipc_bearer *b);
+static void tipc_aead_decrypt_done(struct crypto_async_request *base, int err);
+static inline int tipc_ehdr_size(struct tipc_ehdr *ehdr);
+static int tipc_ehdr_build(struct net *net, struct tipc_aead *aead,
+			   u8 tx_key, struct sk_buff *skb,
+			   struct tipc_crypto *__rx);
+static inline void tipc_crypto_key_set_state(struct tipc_crypto *c,
+					     u8 new_passive,
+					     u8 new_active,
+					     u8 new_pending);
+static int tipc_crypto_key_attach(struct tipc_crypto *c,
+				  struct tipc_aead *aead, u8 pos);
+static bool tipc_crypto_key_try_align(struct tipc_crypto *rx, u8 new_pending);
+static struct tipc_aead *tipc_crypto_key_pick_tx(struct tipc_crypto *tx,
+						 struct tipc_crypto *rx,
+						 struct sk_buff *skb);
+static void tipc_crypto_key_synch(struct tipc_crypto *rx, u8 new_rx_active,
+				  struct tipc_msg *hdr);
+static int tipc_crypto_key_revoke(struct net *net, u8 tx_key);
+static void tipc_crypto_rcv_complete(struct net *net, struct tipc_aead *aead,
+				     struct tipc_bearer *b,
+				     struct sk_buff **skb, int err);
+static void tipc_crypto_do_cmd(struct net *net, int cmd);
+static char *tipc_crypto_key_dump(struct tipc_crypto *c, char *buf);
+#ifdef TIPC_CRYPTO_DEBUG
+static char *tipc_key_change_dump(struct tipc_key old, struct tipc_key new,
+				  char *buf);
+#endif
+
+#define key_next(cur) ((cur) % KEY_MAX + 1)
+
+#define tipc_aead_rcu_ptr(rcu_ptr, lock)				\
+	rcu_dereference_protected((rcu_ptr), lockdep_is_held(lock))
+
+#define tipc_aead_rcu_swap(rcu_ptr, ptr, lock)				\
+	rcu_swap_protected((rcu_ptr), (ptr), lockdep_is_held(lock))
+
+#define tipc_aead_rcu_replace(rcu_ptr, ptr, lock)			\
+do {									\
+	typeof(rcu_ptr) __tmp = rcu_dereference_protected((rcu_ptr),	\
+						lockdep_is_held(lock));	\
+	rcu_assign_pointer((rcu_ptr), (ptr));				\
+	tipc_aead_put(__tmp);						\
+} while (0)
+
+#define tipc_crypto_key_detach(rcu_ptr, lock)				\
+	tipc_aead_rcu_replace((rcu_ptr), NULL, lock)
+
+/**
+ * tipc_aead_key_validate - Validate a AEAD user key
+ */
+int tipc_aead_key_validate(struct tipc_aead_key *ukey)
+{
+	int keylen;
+
+	/* Check if algorithm exists */
+	if (unlikely(!crypto_has_alg(ukey->alg_name, 0, 0))) {
+		pr_info("Not found cipher: \"%s\"!\n", ukey->alg_name);
+		return -ENODEV;
+	}
+
+	/* Currently, we only support the "gcm(aes)" cipher algorithm */
+	if (strcmp(ukey->alg_name, "gcm(aes)"))
+		return -ENOTSUPP;
+
+	/* Check if key size is correct */
+	keylen = ukey->keylen - TIPC_AES_GCM_SALT_SIZE;
+	if (unlikely(keylen != TIPC_AES_GCM_KEY_SIZE_128 &&
+		     keylen != TIPC_AES_GCM_KEY_SIZE_192 &&
+		     keylen != TIPC_AES_GCM_KEY_SIZE_256))
+		return -EINVAL;
+
+	return 0;
+}
+
+static struct tipc_aead *tipc_aead_get(struct tipc_aead __rcu *aead)
+{
+	struct tipc_aead *tmp;
+
+	rcu_read_lock();
+	tmp = rcu_dereference(aead);
+	if (unlikely(!tmp || !refcount_inc_not_zero(&tmp->refcnt)))
+		tmp = NULL;
+	rcu_read_unlock();
+
+	return tmp;
+}
+
+static inline void tipc_aead_put(struct tipc_aead *aead)
+{
+	if (aead && refcount_dec_and_test(&aead->refcnt))
+		call_rcu(&aead->rcu, tipc_aead_free);
+}
+
+/**
+ * tipc_aead_free - Release AEAD key incl. all the TFMs in the list
+ * @rp: rcu head pointer
+ */
+static void tipc_aead_free(struct rcu_head *rp)
+{
+	struct tipc_aead *aead = container_of(rp, struct tipc_aead, rcu);
+	struct tipc_tfm *tfm_entry, *head, *tmp;
+
+	if (aead->cloned) {
+		tipc_aead_put(aead->cloned);
+	} else {
+		head = *this_cpu_ptr(aead->tfm_entry);
+		list_for_each_entry_safe(tfm_entry, tmp, &head->list, list) {
+			crypto_free_aead(tfm_entry->tfm);
+			list_del(&tfm_entry->list);
+			kfree(tfm_entry);
+		}
+		/* Free the head */
+		crypto_free_aead(head->tfm);
+		list_del(&head->list);
+		kfree(head);
+	}
+	free_percpu(aead->tfm_entry);
+	kfree(aead);
+}
+
+static int tipc_aead_users(struct tipc_aead __rcu *aead)
+{
+	struct tipc_aead *tmp;
+	int users = 0;
+
+	rcu_read_lock();
+	tmp = rcu_dereference(aead);
+	if (tmp)
+		users = atomic_read(&tmp->users);
+	rcu_read_unlock();
+
+	return users;
+}
+
+static void tipc_aead_users_inc(struct tipc_aead __rcu *aead, int lim)
+{
+	struct tipc_aead *tmp;
+
+	rcu_read_lock();
+	tmp = rcu_dereference(aead);
+	if (tmp)
+		atomic_add_unless(&tmp->users, 1, lim);
+	rcu_read_unlock();
+}
+
+static void tipc_aead_users_dec(struct tipc_aead __rcu *aead, int lim)
+{
+	struct tipc_aead *tmp;
+
+	rcu_read_lock();
+	tmp = rcu_dereference(aead);
+	if (tmp)
+		atomic_add_unless(&rcu_dereference(aead)->users, -1, lim);
+	rcu_read_unlock();
+}
+
+static void tipc_aead_users_set(struct tipc_aead __rcu *aead, int val)
+{
+	struct tipc_aead *tmp;
+	int cur;
+
+	rcu_read_lock();
+	tmp = rcu_dereference(aead);
+	if (tmp) {
+		do {
+			cur = atomic_read(&tmp->users);
+			if (cur == val)
+				break;
+		} while (atomic_cmpxchg(&tmp->users, cur, val) != cur);
+	}
+	rcu_read_unlock();
+}
+
+/**
+ * tipc_aead_tfm_next - Move TFM entry to the next one in list and return it
+ */
+static struct crypto_aead *tipc_aead_tfm_next(struct tipc_aead *aead)
+{
+	struct tipc_tfm **tfm_entry = this_cpu_ptr(aead->tfm_entry);
+
+	*tfm_entry = list_next_entry(*tfm_entry, list);
+	return (*tfm_entry)->tfm;
+}
+
+/**
+ * tipc_aead_init - Initiate TIPC AEAD
+ * @aead: returned new TIPC AEAD key handle pointer
+ * @ukey: pointer to user key data
+ * @mode: the key mode
+ *
+ * Allocate a (list of) new cipher transformation (TFM) with the specific user
+ * key data if valid. The number of the allocated TFMs can be set via the sysfs
+ * "net/tipc/max_tfms" first.
+ * Also, all the other AEAD data are also initialized.
+ *
+ * Return: 0 if the initiation is successful, otherwise: < 0
+ */
+static int tipc_aead_init(struct tipc_aead **aead, struct tipc_aead_key *ukey,
+			  u8 mode)
+{
+	struct tipc_tfm *tfm_entry, *head;
+	struct crypto_aead *tfm;
+	struct tipc_aead *tmp;
+	int keylen, err, cpu;
+	int tfm_cnt = 0;
+
+	if (unlikely(*aead))
+		return -EEXIST;
+
+	/* Allocate a new AEAD */
+	tmp = kzalloc(sizeof(*tmp), GFP_ATOMIC);
+	if (unlikely(!tmp))
+		return -ENOMEM;
+
+	/* The key consists of two parts: [AES-KEY][SALT] */
+	keylen = ukey->keylen - TIPC_AES_GCM_SALT_SIZE;
+
+	/* Allocate per-cpu TFM entry pointer */
+	tmp->tfm_entry = alloc_percpu(struct tipc_tfm *);
+	if (!tmp->tfm_entry) {
+		kzfree(tmp);
+		return -ENOMEM;
+	}
+
+	/* Make a list of TFMs with the user key data */
+	do {
+		tfm = crypto_alloc_aead(ukey->alg_name, 0, 0);
+		if (IS_ERR(tfm)) {
+			err = PTR_ERR(tfm);
+			break;
+		}
+
+		if (unlikely(!tfm_cnt &&
+			     crypto_aead_ivsize(tfm) != TIPC_AES_GCM_IV_SIZE)) {
+			crypto_free_aead(tfm);
+			err = -ENOTSUPP;
+			break;
+		}
+
+		err = crypto_aead_setauthsize(tfm, TIPC_AES_GCM_TAG_SIZE);
+		err |= crypto_aead_setkey(tfm, ukey->key, keylen);
+		if (unlikely(err)) {
+			crypto_free_aead(tfm);
+			break;
+		}
+
+		tfm_entry = kmalloc(sizeof(*tfm_entry), GFP_KERNEL);
+		if (unlikely(!tfm_entry)) {
+			crypto_free_aead(tfm);
+			err = -ENOMEM;
+			break;
+		}
+		INIT_LIST_HEAD(&tfm_entry->list);
+		tfm_entry->tfm = tfm;
+
+		/* First entry? */
+		if (!tfm_cnt) {
+			head = tfm_entry;
+			for_each_possible_cpu(cpu) {
+				*per_cpu_ptr(tmp->tfm_entry, cpu) = head;
+			}
+		} else {
+			list_add_tail(&tfm_entry->list, &head->list);
+		}
+
+	} while (++tfm_cnt < sysctl_tipc_max_tfms);
+
+	/* Not any TFM is allocated? */
+	if (!tfm_cnt) {
+		free_percpu(tmp->tfm_entry);
+		kzfree(tmp);
+		return err;
+	}
+
+	/* Copy some chars from the user key as a hint */
+	memcpy(tmp->hint, ukey->key, TIPC_AEAD_HINT_LEN);
+	tmp->hint[TIPC_AEAD_HINT_LEN] = '\0';
+
+	/* Initialize the other data */
+	tmp->mode = mode;
+	tmp->cloned = NULL;
+	tmp->authsize = TIPC_AES_GCM_TAG_SIZE;
+	memcpy(&tmp->salt, ukey->key + keylen, TIPC_AES_GCM_SALT_SIZE);
+	atomic_set(&tmp->users, 0);
+	atomic64_set(&tmp->seqno, 0);
+	refcount_set(&tmp->refcnt, 1);
+
+	*aead = tmp;
+	return 0;
+}
+
+/**
+ * tipc_aead_clone - Clone a TIPC AEAD key
+ * @dst: dest key for the cloning
+ * @src: source key to clone from
+ *
+ * Make a "copy" of the source AEAD key data to the dest, the TFMs list is
+ * common for the keys.
+ * A reference to the source is hold in the "cloned" pointer for the later
+ * freeing purposes.
+ *
+ * Note: this must be done in cluster-key mode only!
+ * Return: 0 in case of success, otherwise < 0
+ */
+static int tipc_aead_clone(struct tipc_aead **dst, struct tipc_aead *src)
+{
+	struct tipc_aead *aead;
+	int cpu;
+
+	if (!src)
+		return -ENOKEY;
+
+	if (src->mode != CLUSTER_KEY)
+		return -EINVAL;
+
+	if (unlikely(*dst))
+		return -EEXIST;
+
+	aead = kzalloc(sizeof(*aead), GFP_ATOMIC);
+	if (unlikely(!aead))
+		return -ENOMEM;
+
+	aead->tfm_entry = alloc_percpu_gfp(struct tipc_tfm *, GFP_ATOMIC);
+	if (unlikely(!aead->tfm_entry)) {
+		kzfree(aead);
+		return -ENOMEM;
+	}
+
+	for_each_possible_cpu(cpu) {
+		*per_cpu_ptr(aead->tfm_entry, cpu) =
+				*per_cpu_ptr(src->tfm_entry, cpu);
+	}
+
+	memcpy(aead->hint, src->hint, sizeof(src->hint));
+	aead->mode = src->mode;
+	aead->salt = src->salt;
+	aead->authsize = src->authsize;
+	atomic_set(&aead->users, 0);
+	atomic64_set(&aead->seqno, 0);
+	refcount_set(&aead->refcnt, 1);
+
+	WARN_ON(!refcount_inc_not_zero(&src->refcnt));
+	aead->cloned = src;
+
+	*dst = aead;
+	return 0;
+}
+
+/**
+ * tipc_aead_mem_alloc - Allocate memory for AEAD request operations
+ * @tfm: cipher handle to be registered with the request
+ * @crypto_ctx_size: size of crypto context for callback
+ * @iv: returned pointer to IV data
+ * @req: returned pointer to AEAD request data
+ * @sg: returned pointer to SG lists
+ * @nsg: number of SG lists to be allocated
+ *
+ * Allocate memory to store the crypto context data, AEAD request, IV and SG
+ * lists, the memory layout is as follows:
+ * crypto_ctx || iv || aead_req || sg[]
+ *
+ * Return: the pointer to the memory areas in case of success, otherwise NULL
+ */
+static void *tipc_aead_mem_alloc(struct crypto_aead *tfm,
+				 unsigned int crypto_ctx_size,
+				 u8 **iv, struct aead_request **req,
+				 struct scatterlist **sg, int nsg)
+{
+	unsigned int iv_size, req_size;
+	unsigned int len;
+	u8 *mem;
+
+	iv_size = crypto_aead_ivsize(tfm);
+	req_size = sizeof(**req) + crypto_aead_reqsize(tfm);
+
+	len = crypto_ctx_size;
+	len += iv_size;
+	len += crypto_aead_alignmask(tfm) & ~(crypto_tfm_ctx_alignment() - 1);
+	len = ALIGN(len, crypto_tfm_ctx_alignment());
+	len += req_size;
+	len = ALIGN(len, __alignof__(struct scatterlist));
+	len += nsg * sizeof(**sg);
+
+	mem = kmalloc(len, GFP_ATOMIC);
+	if (!mem)
+		return NULL;
+
+	*iv = (u8 *)PTR_ALIGN(mem + crypto_ctx_size,
+			      crypto_aead_alignmask(tfm) + 1);
+	*req = (struct aead_request *)PTR_ALIGN(*iv + iv_size,
+						crypto_tfm_ctx_alignment());
+	*sg = (struct scatterlist *)PTR_ALIGN((u8 *)*req + req_size,
+					      __alignof__(struct scatterlist));
+
+	return (void *)mem;
+}
+
+/**
+ * tipc_aead_encrypt - Encrypt a message
+ * @aead: TIPC AEAD key for the message encryption
+ * @skb: the input/output skb
+ * @b: TIPC bearer where the message will be delivered after the encryption
+ * @dst: the destination media address
+ * @__dnode: TIPC dest node if "known"
+ *
+ * Return:
+ * 0                   : if the encryption has completed
+ * -EINPROGRESS/-EBUSY : if a callback will be performed
+ * < 0                 : the encryption has failed
+ */
+static int tipc_aead_encrypt(struct tipc_aead *aead, struct sk_buff *skb,
+			     struct tipc_bearer *b,
+			     struct tipc_media_addr *dst,
+			     struct tipc_node *__dnode)
+{
+	struct crypto_aead *tfm = tipc_aead_tfm_next(aead);
+	struct tipc_crypto_tx_ctx *tx_ctx;
+	struct aead_request *req;
+	struct sk_buff *trailer;
+	struct scatterlist *sg;
+	struct tipc_ehdr *ehdr;
+	int ehsz, len, tailen, nsg, rc;
+	void *ctx;
+	u32 salt;
+	u8 *iv;
+
+	/* Make sure message len at least 4-byte aligned */
+	len = ALIGN(skb->len, 4);
+	tailen = len - skb->len + aead->authsize;
+
+	/* Expand skb tail for authentication tag:
+	 * As for simplicity, we'd have made sure skb having enough tailroom
+	 * for authentication tag @skb allocation. Even when skb is nonlinear
+	 * but there is no frag_list, it should be still fine!
+	 * Otherwise, we must cow it to be a writable buffer with the tailroom.
+	 */
+#ifdef TIPC_CRYPTO_DEBUG
+	SKB_LINEAR_ASSERT(skb);
+	if (tailen > skb_tailroom(skb)) {
+		pr_warn("TX: skb tailroom is not enough: %d, requires: %d\n",
+			skb_tailroom(skb), tailen);
+	}
+#endif
+
+	if (unlikely(!skb_cloned(skb) && tailen <= skb_tailroom(skb))) {
+		nsg = 1;
+		trailer = skb;
+	} else {
+		/* TODO: We could avoid skb_cow_data() if skb has no frag_list
+		 * e.g. by skb_fill_page_desc() to add another page to the skb
+		 * with the wanted tailen... However, page skbs look not often,
+		 * so take it easy now!
+		 * Cloned skbs e.g. from link_xmit() seems no choice though :(
+		 */
+		nsg = skb_cow_data(skb, tailen, &trailer);
+		if (unlikely(nsg < 0)) {
+			pr_err("TX: skb_cow_data() returned %d\n", nsg);
+			return nsg;
+		}
+	}
+
+	pskb_put(skb, trailer, tailen);
+
+	/* Allocate memory for the AEAD operation */
+	ctx = tipc_aead_mem_alloc(tfm, sizeof(*tx_ctx), &iv, &req, &sg, nsg);
+	if (unlikely(!ctx))
+		return -ENOMEM;
+	TIPC_SKB_CB(skb)->crypto_ctx = ctx;
+
+	/* Map skb to the sg lists */
+	sg_init_table(sg, nsg);
+	rc = skb_to_sgvec(skb, sg, 0, skb->len);
+	if (unlikely(rc < 0)) {
+		pr_err("TX: skb_to_sgvec() returned %d, nsg %d!\n", rc, nsg);
+		goto exit;
+	}
+
+	/* Prepare IV: [SALT (4 octets)][SEQNO (8 octets)]
+	 * In case we're in cluster-key mode, SALT is varied by xor-ing with
+	 * the source address (or w0 of id), otherwise with the dest address
+	 * if dest is known.
+	 */
+	ehdr = (struct tipc_ehdr *)skb->data;
+	salt = aead->salt;
+	if (aead->mode == CLUSTER_KEY)
+		salt ^= ehdr->addr; /* __be32 */
+	else if (__dnode)
+		salt ^= tipc_node_get_addr(__dnode);
+	memcpy(iv, &salt, 4);
+	memcpy(iv + 4, (u8 *)&ehdr->seqno, 8);
+
+	/* Prepare request */
+	ehsz = tipc_ehdr_size(ehdr);
+	aead_request_set_tfm(req, tfm);
+	aead_request_set_ad(req, ehsz);
+	aead_request_set_crypt(req, sg, sg, len - ehsz, iv);
+
+	/* Set callback function & data */
+	aead_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG,
+				  tipc_aead_encrypt_done, skb);
+	tx_ctx = (struct tipc_crypto_tx_ctx *)ctx;
+	tx_ctx->aead = aead;
+	tx_ctx->bearer = b;
+	memcpy(&tx_ctx->dst, dst, sizeof(*dst));
+
+	/* Hold bearer */
+	if (unlikely(!tipc_bearer_hold(b))) {
+		rc = -ENODEV;
+		goto exit;
+	}
+
+	/* Now, do encrypt */
+	rc = crypto_aead_encrypt(req);
+	if (rc == -EINPROGRESS || rc == -EBUSY)
+		return rc;
+
+	tipc_bearer_put(b);
+
+exit:
+	kfree(ctx);
+	TIPC_SKB_CB(skb)->crypto_ctx = NULL;
+	return rc;
+}
+
+static void tipc_aead_encrypt_done(struct crypto_async_request *base, int err)
+{
+	struct sk_buff *skb = base->data;
+	struct tipc_crypto_tx_ctx *tx_ctx = TIPC_SKB_CB(skb)->crypto_ctx;
+	struct tipc_bearer *b = tx_ctx->bearer;
+	struct tipc_aead *aead = tx_ctx->aead;
+	struct tipc_crypto *tx = aead->crypto;
+	struct net *net = tx->net;
+
+	switch (err) {
+	case 0:
+		this_cpu_inc(tx->stats->stat[STAT_ASYNC_OK]);
+		if (likely(test_bit(0, &b->up)))
+			b->media->send_msg(net, skb, b, &tx_ctx->dst);
+		else
+			kfree_skb(skb);
+		break;
+	case -EINPROGRESS:
+		return;
+	default:
+		this_cpu_inc(tx->stats->stat[STAT_ASYNC_NOK]);
+		kfree_skb(skb);
+		break;
+	}
+
+	kfree(tx_ctx);
+	tipc_bearer_put(b);
+	tipc_aead_put(aead);
+}
+
+/**
+ * tipc_aead_decrypt - Decrypt an encrypted message
+ * @net: struct net
+ * @aead: TIPC AEAD for the message decryption
+ * @skb: the input/output skb
+ * @b: TIPC bearer where the message has been received
+ *
+ * Return:
+ * 0                   : if the decryption has completed
+ * -EINPROGRESS/-EBUSY : if a callback will be performed
+ * < 0                 : the decryption has failed
+ */
+static int tipc_aead_decrypt(struct net *net, struct tipc_aead *aead,
+			     struct sk_buff *skb, struct tipc_bearer *b)
+{
+	struct tipc_crypto_rx_ctx *rx_ctx;
+	struct aead_request *req;
+	struct crypto_aead *tfm;
+	struct sk_buff *unused;
+	struct scatterlist *sg;
+	struct tipc_ehdr *ehdr;
+	int ehsz, nsg, rc;
+	void *ctx;
+	u32 salt;
+	u8 *iv;
+
+	if (unlikely(!aead))
+		return -ENOKEY;
+
+	/* Cow skb data if needed */
+	if (likely(!skb_cloned(skb) &&
+		   (!skb_is_nonlinear(skb) || !skb_has_frag_list(skb)))) {
+		nsg = 1 + skb_shinfo(skb)->nr_frags;
+	} else {
+		nsg = skb_cow_data(skb, 0, &unused);
+		if (unlikely(nsg < 0)) {
+			pr_err("RX: skb_cow_data() returned %d\n", nsg);
+			return nsg;
+		}
+	}
+
+	/* Allocate memory for the AEAD operation */
+	tfm = tipc_aead_tfm_next(aead);
+	ctx = tipc_aead_mem_alloc(tfm, sizeof(*rx_ctx), &iv, &req, &sg, nsg);
+	if (unlikely(!ctx))
+		return -ENOMEM;
+	TIPC_SKB_CB(skb)->crypto_ctx = ctx;
+
+	/* Map skb to the sg lists */
+	sg_init_table(sg, nsg);
+	rc = skb_to_sgvec(skb, sg, 0, skb->len);
+	if (unlikely(rc < 0)) {
+		pr_err("RX: skb_to_sgvec() returned %d, nsg %d\n", rc, nsg);
+		goto exit;
+	}
+
+	/* Reconstruct IV: */
+	ehdr = (struct tipc_ehdr *)skb->data;
+	salt = aead->salt;
+	if (aead->mode == CLUSTER_KEY)
+		salt ^= ehdr->addr; /* __be32 */
+	else if (ehdr->destined)
+		salt ^= tipc_own_addr(net);
+	memcpy(iv, &salt, 4);
+	memcpy(iv + 4, (u8 *)&ehdr->seqno, 8);
+
+	/* Prepare request */
+	ehsz = tipc_ehdr_size(ehdr);
+	aead_request_set_tfm(req, tfm);
+	aead_request_set_ad(req, ehsz);
+	aead_request_set_crypt(req, sg, sg, skb->len - ehsz, iv);
+
+	/* Set callback function & data */
+	aead_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG,
+				  tipc_aead_decrypt_done, skb);
+	rx_ctx = (struct tipc_crypto_rx_ctx *)ctx;
+	rx_ctx->aead = aead;
+	rx_ctx->bearer = b;
+
+	/* Hold bearer */
+	if (unlikely(!tipc_bearer_hold(b))) {
+		rc = -ENODEV;
+		goto exit;
+	}
+
+	/* Now, do decrypt */
+	rc = crypto_aead_decrypt(req);
+	if (rc == -EINPROGRESS || rc == -EBUSY)
+		return rc;
+
+	tipc_bearer_put(b);
+
+exit:
+	kfree(ctx);
+	TIPC_SKB_CB(skb)->crypto_ctx = NULL;
+	return rc;
+}
+
+static void tipc_aead_decrypt_done(struct crypto_async_request *base, int err)
+{
+	struct sk_buff *skb = base->data;
+	struct tipc_crypto_rx_ctx *rx_ctx = TIPC_SKB_CB(skb)->crypto_ctx;
+	struct tipc_bearer *b = rx_ctx->bearer;
+	struct tipc_aead *aead = rx_ctx->aead;
+	struct tipc_crypto_stats __percpu *stats = aead->crypto->stats;
+	struct net *net = aead->crypto->net;
+
+	switch (err) {
+	case 0:
+		this_cpu_inc(stats->stat[STAT_ASYNC_OK]);
+		break;
+	case -EINPROGRESS:
+		return;
+	default:
+		this_cpu_inc(stats->stat[STAT_ASYNC_NOK]);
+		break;
+	}
+
+	kfree(rx_ctx);
+	tipc_crypto_rcv_complete(net, aead, b, &skb, err);
+	if (likely(skb)) {
+		if (likely(test_bit(0, &b->up)))
+			tipc_rcv(net, skb, b);
+		else
+			kfree_skb(skb);
+	}
+
+	tipc_bearer_put(b);
+}
+
+static inline int tipc_ehdr_size(struct tipc_ehdr *ehdr)
+{
+	return (ehdr->user != LINK_CONFIG) ? EHDR_SIZE : EHDR_CFG_SIZE;
+}
+
+/**
+ * tipc_ehdr_validate - Validate an encryption message
+ * @skb: the message buffer
+ *
+ * Returns "true" if this is a valid encryption message, otherwise "false"
+ */
+bool tipc_ehdr_validate(struct sk_buff *skb)
+{
+	struct tipc_ehdr *ehdr;
+	int ehsz;
+
+	if (unlikely(!pskb_may_pull(skb, EHDR_MIN_SIZE)))
+		return false;
+
+	ehdr = (struct tipc_ehdr *)skb->data;
+	if (unlikely(ehdr->version != TIPC_EVERSION))
+		return false;
+	ehsz = tipc_ehdr_size(ehdr);
+	if (unlikely(!pskb_may_pull(skb, ehsz)))
+		return false;
+	if (unlikely(skb->len <= ehsz + TIPC_AES_GCM_TAG_SIZE))
+		return false;
+	if (unlikely(!ehdr->tx_key))
+		return false;
+
+	return true;
+}
+
+/**
+ * tipc_ehdr_build - Build TIPC encryption message header
+ * @net: struct net
+ * @aead: TX AEAD key to be used for the message encryption
+ * @tx_key: key id used for the message encryption
+ * @skb: input/output message skb
+ * @__rx: RX crypto handle if dest is "known"
+ *
+ * Return: the header size if the building is successful, otherwise < 0
+ */
+static int tipc_ehdr_build(struct net *net, struct tipc_aead *aead,
+			   u8 tx_key, struct sk_buff *skb,
+			   struct tipc_crypto *__rx)
+{
+	struct tipc_msg *hdr = buf_msg(skb);
+	struct tipc_ehdr *ehdr;
+	u32 user = msg_user(hdr);
+	u64 seqno;
+	int ehsz;
+
+	/* Make room for encryption header */
+	ehsz = (user != LINK_CONFIG) ? EHDR_SIZE : EHDR_CFG_SIZE;
+	WARN_ON(skb_headroom(skb) < ehsz);
+	ehdr = (struct tipc_ehdr *)skb_push(skb, ehsz);
+
+	/* Obtain a seqno first:
+	 * Use the key seqno (= cluster wise) if dest is unknown or we're in
+	 * cluster key mode, otherwise it's better for a per-peer seqno!
+	 */
+	if (!__rx || aead->mode == CLUSTER_KEY)
+		seqno = atomic64_inc_return(&aead->seqno);
+	else
+		seqno = atomic64_inc_return(&__rx->sndnxt);
+
+	/* Revoke the key if seqno is wrapped around */
+	if (unlikely(!seqno))
+		return tipc_crypto_key_revoke(net, tx_key);
+
+	/* Word 1-2 */
+	ehdr->seqno = cpu_to_be64(seqno);
+
+	/* Words 0, 3- */
+	ehdr->version = TIPC_EVERSION;
+	ehdr->user = 0;
+	ehdr->keepalive = 0;
+	ehdr->tx_key = tx_key;
+	ehdr->destined = (__rx) ? 1 : 0;
+	ehdr->rx_key_active = (__rx) ? __rx->key.active : 0;
+	ehdr->reserved_1 = 0;
+	ehdr->reserved_2 = 0;
+
+	switch (user) {
+	case LINK_CONFIG:
+		ehdr->user = LINK_CONFIG;
+		memcpy(ehdr->id, tipc_own_id(net), NODE_ID_LEN);
+		break;
+	default:
+		if (user == LINK_PROTOCOL && msg_type(hdr) == STATE_MSG) {
+			ehdr->user = LINK_PROTOCOL;
+			ehdr->keepalive = msg_is_keepalive(hdr);
+		}
+		ehdr->addr = hdr->hdr[3];
+		break;
+	}
+
+	return ehsz;
+}
+
+static inline void tipc_crypto_key_set_state(struct tipc_crypto *c,
+					     u8 new_passive,
+					     u8 new_active,
+					     u8 new_pending)
+{
+#ifdef TIPC_CRYPTO_DEBUG
+	struct tipc_key old = c->key;
+	char buf[32];
+#endif
+
+	c->key.keys = ((new_passive & KEY_MASK) << (KEY_BITS * 2)) |
+		      ((new_active  & KEY_MASK) << (KEY_BITS)) |
+		      ((new_pending & KEY_MASK));
+
+#ifdef TIPC_CRYPTO_DEBUG
+	pr_info("%s(%s): key changing %s ::%pS\n",
+		(c->node) ? "RX" : "TX",
+		(c->node) ? tipc_node_get_id_str(c->node) :
+			    tipc_own_id_string(c->net),
+		tipc_key_change_dump(old, c->key, buf),
+		__builtin_return_address(0));
+#endif
+}
+
+/**
+ * tipc_crypto_key_init - Initiate a new user / AEAD key
+ * @c: TIPC crypto to which new key is attached
+ * @ukey: the user key
+ * @mode: the key mode (CLUSTER_KEY or PER_NODE_KEY)
+ *
+ * A new TIPC AEAD key will be allocated and initiated with the specified user
+ * key, then attached to the TIPC crypto.
+ *
+ * Return: new key id in case of success, otherwise: < 0
+ */
+int tipc_crypto_key_init(struct tipc_crypto *c, struct tipc_aead_key *ukey,
+			 u8 mode)
+{
+	struct tipc_aead *aead = NULL;
+	int rc = 0;
+
+	/* Initiate with the new user key */
+	rc = tipc_aead_init(&aead, ukey, mode);
+
+	/* Attach it to the crypto */
+	if (likely(!rc)) {
+		rc = tipc_crypto_key_attach(c, aead, 0);
+		if (rc < 0)
+			tipc_aead_free(&aead->rcu);
+	}
+
+	pr_info("%s(%s): key initiating, rc %d!\n",
+		(c->node) ? "RX" : "TX",
+		(c->node) ? tipc_node_get_id_str(c->node) :
+			    tipc_own_id_string(c->net),
+		rc);
+
+	return rc;
+}
+
+/**
+ * tipc_crypto_key_attach - Attach a new AEAD key to TIPC crypto
+ * @c: TIPC crypto to which the new AEAD key is attached
+ * @aead: the new AEAD key pointer
+ * @pos: desired slot in the crypto key array, = 0 if any!
+ *
+ * Return: new key id in case of success, otherwise: -EBUSY
+ */
+static int tipc_crypto_key_attach(struct tipc_crypto *c,
+				  struct tipc_aead *aead, u8 pos)
+{
+	u8 new_pending, new_passive, new_key;
+	struct tipc_key key;
+	int rc = -EBUSY;
+
+	spin_lock_bh(&c->lock);
+	key = c->key;
+	if (key.active && key.passive)
+		goto exit;
+	if (key.passive && !tipc_aead_users(c->aead[key.passive]))
+		goto exit;
+	if (key.pending) {
+		if (pos)
+			goto exit;
+		if (tipc_aead_users(c->aead[key.pending]) > 0)
+			goto exit;
+		/* Replace it */
+		new_pending = key.pending;
+		new_passive = key.passive;
+		new_key = new_pending;
+	} else {
+		if (pos) {
+			if (key.active && pos != key_next(key.active)) {
+				new_pending = key.pending;
+				new_passive = pos;
+				new_key = new_passive;
+				goto attach;
+			} else if (!key.active && !key.passive) {
+				new_pending = pos;
+				new_passive = key.passive;
+				new_key = new_pending;
+				goto attach;
+			}
+		}
+		new_pending = key_next(key.active ?: key.passive);
+		new_passive = key.passive;
+		new_key = new_pending;
+	}
+
+attach:
+	aead->crypto = c;
+	tipc_crypto_key_set_state(c, new_passive, key.active, new_pending);
+	tipc_aead_rcu_replace(c->aead[new_key], aead, &c->lock);
+
+	c->working = 1;
+	c->timer1 = jiffies;
+	c->timer2 = jiffies;
+	rc = new_key;
+
+exit:
+	spin_unlock_bh(&c->lock);
+	return rc;
+}
+
+void tipc_crypto_key_flush(struct tipc_crypto *c)
+{
+	int k;
+
+	spin_lock_bh(&c->lock);
+	c->working = 0;
+	tipc_crypto_key_set_state(c, 0, 0, 0);
+	for (k = KEY_MIN; k <= KEY_MAX; k++)
+		tipc_crypto_key_detach(c->aead[k], &c->lock);
+	atomic_set(&c->peer_rx_active, 0);
+	atomic64_set(&c->sndnxt, 0);
+	spin_unlock_bh(&c->lock);
+}
+
+/**
+ * tipc_crypto_key_try_align - Align RX keys if possible
+ * @rx: RX crypto handle
+ * @new_pending: new pending slot if aligned (= TX key from peer)
+ *
+ * Peer has used an unknown key slot, this only happens when peer has left and
+ * rejoned, or we are newcomer.
+ * That means, there must be no active key but a pending key at unaligned slot.
+ * If so, we try to move the pending key to the new slot.
+ * Note: A potential passive key can exist, it will be shifted correspondingly!
+ *
+ * Return: "true" if key is successfully aligned, otherwise "false"
+ */
+static bool tipc_crypto_key_try_align(struct tipc_crypto *rx, u8 new_pending)
+{
+	struct tipc_aead *tmp1, *tmp2 = NULL;
+	struct tipc_key key;
+	bool aligned = false;
+	u8 new_passive = 0;
+	int x;
+
+	spin_lock(&rx->lock);
+	key = rx->key;
+	if (key.pending == new_pending) {
+		aligned = true;
+		goto exit;
+	}
+	if (key.active)
+		goto exit;
+	if (!key.pending)
+		goto exit;
+	if (tipc_aead_users(rx->aead[key.pending]) > 0)
+		goto exit;
+
+	/* Try to "isolate" this pending key first */
+	tmp1 = tipc_aead_rcu_ptr(rx->aead[key.pending], &rx->lock);
+	if (!refcount_dec_if_one(&tmp1->refcnt))
+		goto exit;
+	rcu_assign_pointer(rx->aead[key.pending], NULL);
+
+	/* Move passive key if any */
+	if (key.passive) {
+		tipc_aead_rcu_swap(rx->aead[key.passive], tmp2, &rx->lock);
+		x = (key.passive - key.pending + new_pending) % KEY_MAX;
+		new_passive = (x <= 0) ? x + KEY_MAX : x;
+	}
+
+	/* Re-allocate the key(s) */
+	tipc_crypto_key_set_state(rx, new_passive, 0, new_pending);
+	rcu_assign_pointer(rx->aead[new_pending], tmp1);
+	if (new_passive)
+		rcu_assign_pointer(rx->aead[new_passive], tmp2);
+	refcount_set(&tmp1->refcnt, 1);
+	aligned = true;
+	pr_info("RX(%s): key is aligned!\n", tipc_node_get_id_str(rx->node));
+
+exit:
+	spin_unlock(&rx->lock);
+	return aligned;
+}
+
+/**
+ * tipc_crypto_key_pick_tx - Pick one TX key for message decryption
+ * @tx: TX crypto handle
+ * @rx: RX crypto handle (can be NULL)
+ * @skb: the message skb which will be decrypted later
+ *
+ * This function looks up the existing TX keys and pick one which is suitable
+ * for the message decryption, that must be a cluster key and not used before
+ * on the same message (i.e. recursive).
+ *
+ * Return: the TX AEAD key handle in case of success, otherwise NULL
+ */
+static struct tipc_aead *tipc_crypto_key_pick_tx(struct tipc_crypto *tx,
+						 struct tipc_crypto *rx,
+						 struct sk_buff *skb)
+{
+	struct tipc_skb_cb *skb_cb = TIPC_SKB_CB(skb);
+	struct tipc_aead *aead = NULL;
+	struct tipc_key key = tx->key;
+	u8 k, i = 0;
+
+	/* Initialize data if not yet */
+	if (!skb_cb->tx_clone_deferred) {
+		skb_cb->tx_clone_deferred = 1;
+		memset(&skb_cb->tx_clone_ctx, 0, sizeof(skb_cb->tx_clone_ctx));
+	}
+
+	skb_cb->tx_clone_ctx.rx = rx;
+	if (++skb_cb->tx_clone_ctx.recurs > 2)
+		return NULL;
+
+	/* Pick one TX key */
+	spin_lock(&tx->lock);
+	do {
+		k = (i == 0) ? key.pending :
+			((i == 1) ? key.active : key.passive);
+		if (!k)
+			continue;
+		aead = tipc_aead_rcu_ptr(tx->aead[k], &tx->lock);
+		if (!aead)
+			continue;
+		if (aead->mode != CLUSTER_KEY ||
+		    aead == skb_cb->tx_clone_ctx.last) {
+			aead = NULL;
+			continue;
+		}
+		/* Ok, found one cluster key */
+		skb_cb->tx_clone_ctx.last = aead;
+		WARN_ON(skb->next);
+		skb->next = skb_clone(skb, GFP_ATOMIC);
+		if (unlikely(!skb->next))
+			pr_warn("Failed to clone skb for next round if any\n");
+		WARN_ON(!refcount_inc_not_zero(&aead->refcnt));
+		break;
+	} while (++i < 3);
+	spin_unlock(&tx->lock);
+
+	return aead;
+}
+
+/**
+ * tipc_crypto_key_synch: Synch own key data according to peer key status
+ * @rx: RX crypto handle
+ * @new_rx_active: latest RX active key from peer
+ * @hdr: TIPCv2 message
+ *
+ * This function updates the peer node related data as the peer RX active key
+ * has changed, so the number of TX keys' users on this node are increased and
+ * decreased correspondingly.
+ *
+ * The "per-peer" sndnxt is also reset when the peer key has switched.
+ */
+static void tipc_crypto_key_synch(struct tipc_crypto *rx, u8 new_rx_active,
+				  struct tipc_msg *hdr)
+{
+	struct net *net = rx->net;
+	struct tipc_crypto *tx = tipc_net(net)->crypto_tx;
+	u8 cur_rx_active;
+
+	/* TX might be even not ready yet */
+	if (unlikely(!tx->key.active && !tx->key.pending))
+		return;
+
+	cur_rx_active = atomic_read(&rx->peer_rx_active);
+	if (likely(cur_rx_active == new_rx_active))
+		return;
+
+	/* Make sure this message destined for this node */
+	if (unlikely(msg_short(hdr) ||
+		     msg_destnode(hdr) != tipc_own_addr(net)))
+		return;
+
+	/* Peer RX active key has changed, try to update owns' & TX users */
+	if (atomic_cmpxchg(&rx->peer_rx_active,
+			   cur_rx_active,
+			   new_rx_active) == cur_rx_active) {
+		if (new_rx_active)
+			tipc_aead_users_inc(tx->aead[new_rx_active], INT_MAX);
+		if (cur_rx_active)
+			tipc_aead_users_dec(tx->aead[cur_rx_active], 0);
+
+		atomic64_set(&rx->sndnxt, 0);
+		/* Mark the point TX key users changed */
+		tx->timer1 = jiffies;
+
+#ifdef TIPC_CRYPTO_DEBUG
+		pr_info("TX(%s): key users changed %d-- %d++, peer RX(%s)\n",
+			tipc_own_id_string(net), cur_rx_active,
+			new_rx_active, tipc_node_get_id_str(rx->node));
+#endif
+	}
+}
+
+static int tipc_crypto_key_revoke(struct net *net, u8 tx_key)
+{
+	struct tipc_crypto *tx = tipc_net(net)->crypto_tx;
+	struct tipc_key key;
+
+	spin_lock(&tx->lock);
+	key = tx->key;
+	WARN_ON(!key.active || tx_key != key.active);
+
+	/* Free the active key */
+	tipc_crypto_key_set_state(tx, key.passive, 0, key.pending);
+	tipc_crypto_key_detach(tx->aead[key.active], &tx->lock);
+	spin_unlock(&tx->lock);
+
+	pr_warn("TX(%s): key is revoked!\n", tipc_own_id_string(net));
+	return -EKEYREVOKED;
+}
+
+int tipc_crypto_start(struct tipc_crypto **crypto, struct net *net,
+		      struct tipc_node *node)
+{
+	struct tipc_crypto *c;
+
+	if (*crypto)
+		return -EEXIST;
+
+	/* Allocate crypto */
+	c = kzalloc(sizeof(*c), GFP_ATOMIC);
+	if (!c)
+		return -ENOMEM;
+
+	/* Allocate statistic structure */
+	c->stats = alloc_percpu_gfp(struct tipc_crypto_stats, GFP_ATOMIC);
+	if (!c->stats) {
+		kzfree(c);
+		return -ENOMEM;
+	}
+
+	c->working = 0;
+	c->net = net;
+	c->node = node;
+	tipc_crypto_key_set_state(c, 0, 0, 0);
+	atomic_set(&c->peer_rx_active, 0);
+	atomic64_set(&c->sndnxt, 0);
+	c->timer1 = jiffies;
+	c->timer2 = jiffies;
+	spin_lock_init(&c->lock);
+	*crypto = c;
+
+	return 0;
+}
+
+void tipc_crypto_stop(struct tipc_crypto **crypto)
+{
+	struct tipc_crypto *c, *tx, *rx;
+	bool is_rx;
+	u8 k;
+
+	if (!*crypto)
+		return;
+
+	rcu_read_lock();
+	/* RX stopping? => decrease TX key users if any */
+	is_rx = !!((*crypto)->node);
+	if (is_rx) {
+		rx = *crypto;
+		tx = tipc_net(rx->net)->crypto_tx;
+		k = atomic_read(&rx->peer_rx_active);
+		if (k) {
+			tipc_aead_users_dec(tx->aead[k], 0);
+			/* Mark the point TX key users changed */
+			tx->timer1 = jiffies;
+		}
+	}
+
+	/* Release AEAD keys */
+	c = *crypto;
+	for (k = KEY_MIN; k <= KEY_MAX; k++)
+		tipc_aead_put(rcu_dereference(c->aead[k]));
+	rcu_read_unlock();
+
+	pr_warn("%s(%s) has been purged, node left!\n",
+		(is_rx) ? "RX" : "TX",
+		(is_rx) ? tipc_node_get_id_str((*crypto)->node) :
+			  tipc_own_id_string((*crypto)->net));
+
+	/* Free this crypto statistics */
+	free_percpu(c->stats);
+
+	*crypto = NULL;
+	kzfree(c);
+}
+
+void tipc_crypto_timeout(struct tipc_crypto *rx)
+{
+	struct tipc_net *tn = tipc_net(rx->net);
+	struct tipc_crypto *tx = tn->crypto_tx;
+	struct tipc_key key;
+	u8 new_pending, new_passive;
+	int cmd;
+
+	/* TX key activating:
+	 * The pending key (users > 0) -> active
+	 * The active key if any (users == 0) -> free
+	 */
+	spin_lock(&tx->lock);
+	key = tx->key;
+	if (key.active && tipc_aead_users(tx->aead[key.active]) > 0)
+		goto s1;
+	if (!key.pending || tipc_aead_users(tx->aead[key.pending]) <= 0)
+		goto s1;
+	if (time_before(jiffies, tx->timer1 + TIPC_TX_LASTING_LIM))
+		goto s1;
+
+	tipc_crypto_key_set_state(tx, key.passive, key.pending, 0);
+	if (key.active)
+		tipc_crypto_key_detach(tx->aead[key.active], &tx->lock);
+	this_cpu_inc(tx->stats->stat[STAT_SWITCHES]);
+	pr_info("TX(%s): key %d is activated!\n", tipc_own_id_string(tx->net),
+		key.pending);
+
+s1:
+	spin_unlock(&tx->lock);
+
+	/* RX key activating:
+	 * The pending key (users > 0) -> active
+	 * The active key if any -> passive, freed later
+	 */
+	spin_lock(&rx->lock);
+	key = rx->key;
+	if (!key.pending || tipc_aead_users(rx->aead[key.pending]) <= 0)
+		goto s2;
+
+	new_pending = (key.passive &&
+		       !tipc_aead_users(rx->aead[key.passive])) ?
+				       key.passive : 0;
+	new_passive = (key.active) ?: ((new_pending) ? 0 : key.passive);
+	tipc_crypto_key_set_state(rx, new_passive, key.pending, new_pending);
+	this_cpu_inc(rx->stats->stat[STAT_SWITCHES]);
+	pr_info("RX(%s): key %d is activated!\n",
+		tipc_node_get_id_str(rx->node),	key.pending);
+	goto s5;
+
+s2:
+	/* RX key "faulty" switching:
+	 * The faulty pending key (users < -30) -> passive
+	 * The passive key (users = 0) -> pending
+	 * Note: This only happens after RX deactivated - s3!
+	 */
+	key = rx->key;
+	if (!key.pending || tipc_aead_users(rx->aead[key.pending]) > -30)
+		goto s3;
+	if (!key.passive || tipc_aead_users(rx->aead[key.passive]) != 0)
+		goto s3;
+
+	new_pending = key.passive;
+	new_passive = key.pending;
+	tipc_crypto_key_set_state(rx, new_passive, key.active, new_pending);
+	goto s5;
+
+s3:
+	/* RX key deactivating:
+	 * The passive key if any -> pending
+	 * The active key -> passive (users = 0) / pending
+	 * The pending key if any -> passive (users = 0)
+	 */
+	key = rx->key;
+	if (!key.active)
+		goto s4;
+	if (time_before(jiffies, rx->timer1 + TIPC_RX_ACTIVE_LIM))
+		goto s4;
+
+	new_pending = (key.passive) ?: key.active;
+	new_passive = (key.passive) ? key.active : key.pending;
+	tipc_aead_users_set(rx->aead[new_pending], 0);
+	if (new_passive)
+		tipc_aead_users_set(rx->aead[new_passive], 0);
+	tipc_crypto_key_set_state(rx, new_passive, 0, new_pending);
+	pr_info("RX(%s): key %d is deactivated!\n",
+		tipc_node_get_id_str(rx->node), key.active);
+	goto s5;
+
+s4:
+	/* RX key passive -> freed: */
+	key = rx->key;
+	if (!key.passive || !tipc_aead_users(rx->aead[key.passive]))
+		goto s5;
+	if (time_before(jiffies, rx->timer2 + TIPC_RX_PASSIVE_LIM))
+		goto s5;
+
+	tipc_crypto_key_set_state(rx, 0, key.active, key.pending);
+	tipc_crypto_key_detach(rx->aead[key.passive], &rx->lock);
+	pr_info("RX(%s): key %d is freed!\n", tipc_node_get_id_str(rx->node),
+		key.passive);
+
+s5:
+	spin_unlock(&rx->lock);
+
+	/* Limit max_tfms & do debug commands if needed */
+	if (likely(sysctl_tipc_max_tfms <= TIPC_MAX_TFMS_LIM))
+		return;
+
+	cmd = sysctl_tipc_max_tfms;
+	sysctl_tipc_max_tfms = TIPC_MAX_TFMS_DEF;
+	tipc_crypto_do_cmd(rx->net, cmd);
+}
+
+/**
+ * tipc_crypto_xmit - Build & encrypt TIPC message for xmit
+ * @net: struct net
+ * @skb: input/output message skb pointer
+ * @b: bearer used for xmit later
+ * @dst: destination media address
+ * @__dnode: destination node for reference if any
+ *
+ * First, build an encryption message header on the top of the message, then
+ * encrypt the original TIPC message by using the active or pending TX key.
+ * If the encryption is successful, the encrypted skb is returned directly or
+ * via the callback.
+ * Otherwise, the skb is freed!
+ *
+ * Return:
+ * 0                   : the encryption has succeeded (or no encryption)
+ * -EINPROGRESS/-EBUSY : the encryption is ongoing, a callback will be made
+ * -ENOKEK             : the encryption has failed due to no key
+ * -EKEYREVOKED        : the encryption has failed due to key revoked
+ * -ENOMEM             : the encryption has failed due to no memory
+ * < 0                 : the encryption has failed due to other reasons
+ */
+int tipc_crypto_xmit(struct net *net, struct sk_buff **skb,
+		     struct tipc_bearer *b, struct tipc_media_addr *dst,
+		     struct tipc_node *__dnode)
+{
+	struct tipc_crypto *__rx = tipc_node_crypto_rx(__dnode);
+	struct tipc_crypto *tx = tipc_net(net)->crypto_tx;
+	struct tipc_crypto_stats __percpu *stats = tx->stats;
+	struct tipc_key key = tx->key;
+	struct tipc_aead *aead = NULL;
+	struct sk_buff *probe;
+	int rc = -ENOKEY;
+	u8 tx_key;
+
+	/* No encryption? */
+	if (!tx->working)
+		return 0;
+
+	/* Try with the pending key if available and:
+	 * 1) This is the only choice (i.e. no active key) or;
+	 * 2) Peer has switched to this key (unicast only) or;
+	 * 3) It is time to do a pending key probe;
+	 */
+	if (unlikely(key.pending)) {
+		tx_key = key.pending;
+		if (!key.active)
+			goto encrypt;
+		if (__rx && atomic_read(&__rx->peer_rx_active) == tx_key)
+			goto encrypt;
+		if (TIPC_SKB_CB(*skb)->probe)
+			goto encrypt;
+		if (!__rx &&
+		    time_after(jiffies, tx->timer2 + TIPC_TX_PROBE_LIM)) {
+			tx->timer2 = jiffies;
+			probe = skb_clone(*skb, GFP_ATOMIC);
+			if (probe) {
+				TIPC_SKB_CB(probe)->probe = 1;
+				tipc_crypto_xmit(net, &probe, b, dst, __dnode);
+				if (probe)
+					b->media->send_msg(net, probe, b, dst);
+			}
+		}
+	}
+	/* Else, use the active key if any */
+	if (likely(key.active)) {
+		tx_key = key.active;
+		goto encrypt;
+	}
+	goto exit;
+
+encrypt:
+	aead = tipc_aead_get(tx->aead[tx_key]);
+	if (unlikely(!aead))
+		goto exit;
+	rc = tipc_ehdr_build(net, aead, tx_key, *skb, __rx);
+	if (likely(rc > 0))
+		rc = tipc_aead_encrypt(aead, *skb, b, dst, __dnode);
+
+exit:
+	switch (rc) {
+	case 0:
+		this_cpu_inc(stats->stat[STAT_OK]);
+		break;
+	case -EINPROGRESS:
+	case -EBUSY:
+		this_cpu_inc(stats->stat[STAT_ASYNC]);
+		*skb = NULL;
+		return rc;
+	default:
+		this_cpu_inc(stats->stat[STAT_NOK]);
+		if (rc == -ENOKEY)
+			this_cpu_inc(stats->stat[STAT_NOKEYS]);
+		else if (rc == -EKEYREVOKED)
+			this_cpu_inc(stats->stat[STAT_BADKEYS]);
+		kfree_skb(*skb);
+		*skb = NULL;
+		break;
+	}
+
+	tipc_aead_put(aead);
+	return rc;
+}
+
+/**
+ * tipc_crypto_rcv - Decrypt an encrypted TIPC message from peer
+ * @net: struct net
+ * @rx: RX crypto handle
+ * @skb: input/output message skb pointer
+ * @b: bearer where the message has been received
+ *
+ * If the decryption is successful, the decrypted skb is returned directly or
+ * as the callback, the encryption header and auth tag will be trimed out
+ * before forwarding to tipc_rcv() via the tipc_crypto_rcv_complete().
+ * Otherwise, the skb will be freed!
+ * Note: RX key(s) can be re-aligned, or in case of no key suitable, TX
+ * cluster key(s) can be taken for decryption (- recursive).
+ *
+ * Return:
+ * 0                   : the decryption has successfully completed
+ * -EINPROGRESS/-EBUSY : the decryption is ongoing, a callback will be made
+ * -ENOKEY             : the decryption has failed due to no key
+ * -EBADMSG            : the decryption has failed due to bad message
+ * -ENOMEM             : the decryption has failed due to no memory
+ * < 0                 : the decryption has failed due to other reasons
+ */
+int tipc_crypto_rcv(struct net *net, struct tipc_crypto *rx,
+		    struct sk_buff **skb, struct tipc_bearer *b)
+{
+	struct tipc_crypto *tx = tipc_net(net)->crypto_tx;
+	struct tipc_crypto_stats __percpu *stats;
+	struct tipc_aead *aead = NULL;
+	struct tipc_key key;
+	int rc = -ENOKEY;
+	u8 tx_key = 0;
+
+	/* New peer?
+	 * Let's try with TX key (i.e. cluster mode) & verify the skb first!
+	 */
+	if (unlikely(!rx))
+		goto pick_tx;
+
+	/* Pick RX key according to TX key, three cases are possible:
+	 * 1) The current active key (likely) or;
+	 * 2) The pending (new or deactivated) key (if any) or;
+	 * 3) The passive or old active key (i.e. users > 0);
+	 */
+	tx_key = ((struct tipc_ehdr *)(*skb)->data)->tx_key;
+	key = rx->key;
+	if (likely(tx_key == key.active))
+		goto decrypt;
+	if (tx_key == key.pending)
+		goto decrypt;
+	if (tx_key == key.passive) {
+		rx->timer2 = jiffies;
+		if (tipc_aead_users(rx->aead[key.passive]) > 0)
+			goto decrypt;
+	}
+
+	/* Unknown key, let's try to align RX key(s) */
+	if (tipc_crypto_key_try_align(rx, tx_key))
+		goto decrypt;
+
+pick_tx:
+	/* No key suitable? Try to pick one from TX... */
+	aead = tipc_crypto_key_pick_tx(tx, rx, *skb);
+	if (aead)
+		goto decrypt;
+	goto exit;
+
+decrypt:
+	rcu_read_lock();
+	if (!aead)
+		aead = tipc_aead_get(rx->aead[tx_key]);
+	rc = tipc_aead_decrypt(net, aead, *skb, b);
+	rcu_read_unlock();
+
+exit:
+	stats = ((rx) ?: tx)->stats;
+	switch (rc) {
+	case 0:
+		this_cpu_inc(stats->stat[STAT_OK]);
+		break;
+	case -EINPROGRESS:
+	case -EBUSY:
+		this_cpu_inc(stats->stat[STAT_ASYNC]);
+		*skb = NULL;
+		return rc;
+	default:
+		this_cpu_inc(stats->stat[STAT_NOK]);
+		if (rc == -ENOKEY) {
+			kfree_skb(*skb);
+			*skb = NULL;
+			if (rx)
+				tipc_node_put(rx->node);
+			this_cpu_inc(stats->stat[STAT_NOKEYS]);
+			return rc;
+		} else if (rc == -EBADMSG) {
+			this_cpu_inc(stats->stat[STAT_BADMSGS]);
+		}
+		break;
+	}
+
+	tipc_crypto_rcv_complete(net, aead, b, skb, rc);
+	return rc;
+}
+
+static void tipc_crypto_rcv_complete(struct net *net, struct tipc_aead *aead,
+				     struct tipc_bearer *b,
+				     struct sk_buff **skb, int err)
+{
+	struct tipc_skb_cb *skb_cb = TIPC_SKB_CB(*skb);
+	struct tipc_crypto *rx = aead->crypto;
+	struct tipc_aead *tmp = NULL;
+	struct tipc_ehdr *ehdr;
+	struct tipc_node *n;
+	u8 rx_key_active;
+	bool destined;
+
+	/* Is this completed by TX? */
+	if (unlikely(!rx->node)) {
+		rx = skb_cb->tx_clone_ctx.rx;
+#ifdef TIPC_CRYPTO_DEBUG
+		pr_info("TX->RX(%s): err %d, aead %p, skb->next %p, flags %x\n",
+			(rx) ? tipc_node_get_id_str(rx->node) : "-", err, aead,
+			(*skb)->next, skb_cb->flags);
+		pr_info("skb_cb [recurs %d, last %p], tx->aead [%p %p %p]\n",
+			skb_cb->tx_clone_ctx.recurs, skb_cb->tx_clone_ctx.last,
+			aead->crypto->aead[1], aead->crypto->aead[2],
+			aead->crypto->aead[3]);
+#endif
+		if (unlikely(err)) {
+			if (err == -EBADMSG && (*skb)->next)
+				tipc_rcv(net, (*skb)->next, b);
+			goto free_skb;
+		}
+
+		if (likely((*skb)->next)) {
+			kfree_skb((*skb)->next);
+			(*skb)->next = NULL;
+		}
+		ehdr = (struct tipc_ehdr *)(*skb)->data;
+		if (!rx) {
+			WARN_ON(ehdr->user != LINK_CONFIG);
+			n = tipc_node_create(net, 0, ehdr->id, 0xffffu, 0,
+					     true);
+			rx = tipc_node_crypto_rx(n);
+			if (unlikely(!rx))
+				goto free_skb;
+		}
+
+		/* Skip cloning this time as we had a RX pending key */
+		if (rx->key.pending)
+			goto rcv;
+		if (tipc_aead_clone(&tmp, aead) < 0)
+			goto rcv;
+		if (tipc_crypto_key_attach(rx, tmp, ehdr->tx_key) < 0) {
+			tipc_aead_free(&tmp->rcu);
+			goto rcv;
+		}
+		tipc_aead_put(aead);
+		aead = tipc_aead_get(tmp);
+	}
+
+	if (unlikely(err)) {
+		tipc_aead_users_dec(aead, INT_MIN);
+		goto free_skb;
+	}
+
+	/* Set the RX key's user */
+	tipc_aead_users_set(aead, 1);
+
+rcv:
+	/* Mark this point, RX works */
+	rx->timer1 = jiffies;
+
+	/* Remove ehdr & auth. tag prior to tipc_rcv() */
+	ehdr = (struct tipc_ehdr *)(*skb)->data;
+	destined = ehdr->destined;
+	rx_key_active = ehdr->rx_key_active;
+	skb_pull(*skb, tipc_ehdr_size(ehdr));
+	pskb_trim(*skb, (*skb)->len - aead->authsize);
+
+	/* Validate TIPCv2 message */
+	if (unlikely(!tipc_msg_validate(skb))) {
+		pr_err_ratelimited("Packet dropped after decryption!\n");
+		goto free_skb;
+	}
+
+	/* Update peer RX active key & TX users */
+	if (destined)
+		tipc_crypto_key_synch(rx, rx_key_active, buf_msg(*skb));
+
+	/* Mark skb decrypted */
+	skb_cb->decrypted = 1;
+
+	/* Clear clone cxt if any */
+	if (likely(!skb_cb->tx_clone_deferred))
+		goto exit;
+	skb_cb->tx_clone_deferred = 0;
+	memset(&skb_cb->tx_clone_ctx, 0, sizeof(skb_cb->tx_clone_ctx));
+	goto exit;
+
+free_skb:
+	kfree_skb(*skb);
+	*skb = NULL;
+
+exit:
+	tipc_aead_put(aead);
+	if (rx)
+		tipc_node_put(rx->node);
+}
+
+static void tipc_crypto_do_cmd(struct net *net, int cmd)
+{
+	struct tipc_net *tn = tipc_net(net);
+	struct tipc_crypto *tx = tn->crypto_tx, *rx;
+	struct list_head *p;
+	unsigned int stat;
+	int i, j, cpu;
+	char buf[200];
+
+	/* Currently only one command is supported */
+	switch (cmd) {
+	case 0xfff1:
+		goto print_stats;
+	default:
+		return;
+	}
+
+print_stats:
+	/* Print a header */
+	pr_info("\n=============== TIPC Crypto Statistics ===============\n\n");
+
+	/* Print key status */
+	pr_info("Key status:\n");
+	pr_info("TX(%7.7s)\n%s", tipc_own_id_string(net),
+		tipc_crypto_key_dump(tx, buf));
+
+	rcu_read_lock();
+	for (p = tn->node_list.next; p != &tn->node_list; p = p->next) {
+		rx = tipc_node_crypto_rx_by_list(p);
+		pr_info("RX(%7.7s)\n%s", tipc_node_get_id_str(rx->node),
+			tipc_crypto_key_dump(rx, buf));
+	}
+	rcu_read_unlock();
+
+	/* Print crypto statistics */
+	for (i = 0, j = 0; i < MAX_STATS; i++)
+		j += scnprintf(buf + j, 200 - j, "|%11s ", hstats[i]);
+	pr_info("\nCounter     %s", buf);
+
+	memset(buf, '-', 115);
+	buf[115] = '\0';
+	pr_info("%s\n", buf);
+
+	j = scnprintf(buf, 200, "TX(%7.7s) ", tipc_own_id_string(net));
+	for_each_possible_cpu(cpu) {
+		for (i = 0; i < MAX_STATS; i++) {
+			stat = per_cpu_ptr(tx->stats, cpu)->stat[i];
+			j += scnprintf(buf + j, 200 - j, "|%11d ", stat);
+		}
+		pr_info("%s", buf);
+		j = scnprintf(buf, 200, "%12s", " ");
+	}
+
+	rcu_read_lock();
+	for (p = tn->node_list.next; p != &tn->node_list; p = p->next) {
+		rx = tipc_node_crypto_rx_by_list(p);
+		j = scnprintf(buf, 200, "RX(%7.7s) ",
+			      tipc_node_get_id_str(rx->node));
+		for_each_possible_cpu(cpu) {
+			for (i = 0; i < MAX_STATS; i++) {
+				stat = per_cpu_ptr(rx->stats, cpu)->stat[i];
+				j += scnprintf(buf + j, 200 - j, "|%11d ",
+					       stat);
+			}
+			pr_info("%s", buf);
+			j = scnprintf(buf, 200, "%12s", " ");
+		}
+	}
+	rcu_read_unlock();
+
+	pr_info("\n======================== Done ========================\n");
+}
+
+static char *tipc_crypto_key_dump(struct tipc_crypto *c, char *buf)
+{
+	struct tipc_key key = c->key;
+	struct tipc_aead *aead;
+	int k, i = 0;
+	char *s;
+
+	for (k = KEY_MIN; k <= KEY_MAX; k++) {
+		if (k == key.passive)
+			s = "PAS";
+		else if (k == key.active)
+			s = "ACT";
+		else if (k == key.pending)
+			s = "PEN";
+		else
+			s = "-";
+		i += scnprintf(buf + i, 200 - i, "\tKey%d: %s", k, s);
+
+		rcu_read_lock();
+		aead = rcu_dereference(c->aead[k]);
+		if (aead)
+			i += scnprintf(buf + i, 200 - i,
+				       "{\"%s...\", \"%s\"}/%d:%d",
+				       aead->hint,
+				       (aead->mode == CLUSTER_KEY) ? "c" : "p",
+				       atomic_read(&aead->users),
+				       refcount_read(&aead->refcnt));
+		rcu_read_unlock();
+		i += scnprintf(buf + i, 200 - i, "\n");
+	}
+
+	if (c->node)
+		i += scnprintf(buf + i, 200 - i, "\tPeer RX active: %d\n",
+			       atomic_read(&c->peer_rx_active));
+
+	return buf;
+}
+
+#ifdef TIPC_CRYPTO_DEBUG
+static char *tipc_key_change_dump(struct tipc_key old, struct tipc_key new,
+				  char *buf)
+{
+	struct tipc_key *key = &old;
+	int k, i = 0;
+	char *s;
+
+	/* Output format: "[%s %s %s] -> [%s %s %s]", max len = 32 */
+again:
+	i += scnprintf(buf + i, 32 - i, "[");
+	for (k = KEY_MIN; k <= KEY_MAX; k++) {
+		if (k == key->passive)
+			s = "pas";
+		else if (k == key->active)
+			s = "act";
+		else if (k == key->pending)
+			s = "pen";
+		else
+			s = "-";
+		i += scnprintf(buf + i, 32 - i,
+			       (k != KEY_MAX) ? "%s " : "%s", s);
+	}
+	if (key != &new) {
+		i += scnprintf(buf + i, 32 - i, "] -> ");
+		key = &new;
+		goto again;
+	}
+	i += scnprintf(buf + i, 32 - i, "]");
+	return buf;
+}
+#endif