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-rw-r--r--net/tipc/crypto.c2475
1 files changed, 2475 insertions, 0 deletions
diff --git a/net/tipc/crypto.c b/net/tipc/crypto.c
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+++ b/net/tipc/crypto.c
@@ -0,0 +1,2475 @@
+// 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/rng.h>
+#include "crypto.h"
+#include "msg.h"
+#include "bcast.h"
+
+#define TIPC_TX_GRACE_PERIOD msecs_to_jiffies(5000) /* 5s */
+#define TIPC_TX_LASTING_TIME msecs_to_jiffies(10000) /* 10s */
+#define TIPC_RX_ACTIVE_LIM msecs_to_jiffies(3000) /* 3s */
+#define TIPC_RX_PASSIVE_LIM msecs_to_jiffies(15000) /* 15s */
+
+#define TIPC_MAX_TFMS_DEF 10
+#define TIPC_MAX_TFMS_LIM 1000
+
+#define TIPC_REKEYING_INTV_DEF (60 * 24) /* default: 1 day */
+
+/*
+ * TIPC Key ids
+ */
+enum {
+ KEY_MASTER = 0,
+ KEY_MIN = KEY_MASTER,
+ KEY_1 = 1,
+ 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;
+/* Key exchange switch, default: on */
+int sysctl_tipc_key_exchange_enabled __read_mostly = 1;
+
+/*
+ * 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
+ * @tfm: cipher handle/key
+ * @list: linked 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
+ * @key: the aead key
+ * @gen: the key's generation
+ * @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[2 * TIPC_AEAD_HINT_LEN + 1];
+ struct rcu_head rcu;
+ struct tipc_aead_key *key;
+ u16 gen;
+
+ atomic64_t seqno ____cacheline_aligned;
+ refcount_t refcnt ____cacheline_aligned;
+
+} ____cacheline_aligned;
+
+/**
+ * struct tipc_crypto_stats - TIPC Crypto statistics
+ * @stat: array of 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_gen: TX/RX key generation
+ * @key: the key states
+ * @skey_mode: session key's mode
+ * @skey: received session key
+ * @wq: common workqueue on TX crypto
+ * @work: delayed work sched for TX/RX
+ * @key_distr: key distributing state
+ * @rekeying_intv: rekeying interval (in minutes)
+ * @stats: the crypto statistics
+ * @name: the crypto name
+ * @sndnxt: the per-peer sndnxt (TX)
+ * @timer1: general timer 1 (jiffies)
+ * @timer2: general timer 2 (jiffies)
+ * @working: the crypto is working or not
+ * @key_master: flag indicates if master key exists
+ * @legacy_user: flag indicates if a peer joins w/o master key (for bwd comp.)
+ * @nokey: no key indication
+ * @flags: combined flags field
+ * @lock: tipc_key lock
+ */
+struct tipc_crypto {
+ struct net *net;
+ struct tipc_node *node;
+ struct tipc_aead __rcu *aead[KEY_MAX + 1];
+ atomic_t peer_rx_active;
+ u16 key_gen;
+ struct tipc_key key;
+ u8 skey_mode;
+ struct tipc_aead_key *skey;
+ struct workqueue_struct *wq;
+ struct delayed_work work;
+#define KEY_DISTR_SCHED 1
+#define KEY_DISTR_COMPL 2
+ atomic_t key_distr;
+ u32 rekeying_intv;
+
+ struct tipc_crypto_stats __percpu *stats;
+ char name[48];
+
+ atomic64_t sndnxt ____cacheline_aligned;
+ unsigned long timer1;
+ unsigned long timer2;
+ union {
+ struct {
+ u8 working:1;
+ u8 key_master:1;
+ u8 legacy_user:1;
+ u8 nokey: 1;
+ };
+ u8 flags;
+ };
+ 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,
+ bool master_key);
+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,
+ u8 tx_key);
+static void tipc_crypto_key_synch(struct tipc_crypto *rx, struct sk_buff *skb);
+static int tipc_crypto_key_revoke(struct net *net, u8 tx_key);
+static inline void tipc_crypto_clone_msg(struct net *net, struct sk_buff *_skb,
+ struct tipc_bearer *b,
+ struct tipc_media_addr *dst,
+ struct tipc_node *__dnode, u8 type);
+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);
+static char *tipc_key_change_dump(struct tipc_key old, struct tipc_key new,
+ char *buf);
+static int tipc_crypto_key_xmit(struct net *net, struct tipc_aead_key *skey,
+ u16 gen, u8 mode, u32 dnode);
+static bool tipc_crypto_key_rcv(struct tipc_crypto *rx, struct tipc_msg *hdr);
+static void tipc_crypto_work_tx(struct work_struct *work);
+static void tipc_crypto_work_rx(struct work_struct *work);
+static int tipc_aead_key_generate(struct tipc_aead_key *skey);
+
+#define is_tx(crypto) (!(crypto)->node)
+#define is_rx(crypto) (!is_tx(crypto))
+
+#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_replace(rcu_ptr, ptr, lock) \
+do { \
+ struct tipc_aead *__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
+ * @ukey: pointer to user key data
+ * @info: netlink info pointer
+ */
+int tipc_aead_key_validate(struct tipc_aead_key *ukey, struct genl_info *info)
+{
+ int keylen;
+
+ /* Check if algorithm exists */
+ if (unlikely(!crypto_has_alg(ukey->alg_name, 0, 0))) {
+ GENL_SET_ERR_MSG(info, "unable to load the algorithm (module existed?)");
+ return -ENODEV;
+ }
+
+ /* Currently, we only support the "gcm(aes)" cipher algorithm */
+ if (strcmp(ukey->alg_name, "gcm(aes)")) {
+ GENL_SET_ERR_MSG(info, "not supported yet the algorithm");
+ 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)) {
+ GENL_SET_ERR_MSG(info, "incorrect key length (20, 28 or 36 octets?)");
+ return -EKEYREJECTED;
+ }
+
+ return 0;
+}
+
+/**
+ * tipc_aead_key_generate - Generate new session key
+ * @skey: input/output key with new content
+ *
+ * Return: 0 in case of success, otherwise < 0
+ */
+static int tipc_aead_key_generate(struct tipc_aead_key *skey)
+{
+ int rc = 0;
+
+ /* Fill the key's content with a random value via RNG cipher */
+ rc = crypto_get_default_rng();
+ if (likely(!rc)) {
+ rc = crypto_rng_get_bytes(crypto_default_rng, skey->key,
+ skey->keylen);
+ crypto_put_default_rng();
+ }
+
+ return rc;
+}
+
+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 = *get_cpu_ptr(aead->tfm_entry);
+ put_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_sensitive(aead->key);
+ 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
+ * @aead: the AEAD key pointer
+ */
+static struct crypto_aead *tipc_aead_tfm_next(struct tipc_aead *aead)
+{
+ struct tipc_tfm **tfm_entry;
+ struct crypto_aead *tfm;
+
+ tfm_entry = get_cpu_ptr(aead->tfm_entry);
+ *tfm_entry = list_next_entry(*tfm_entry, list);
+ tfm = (*tfm_entry)->tfm;
+ put_cpu_ptr(tfm_entry);
+
+ return 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) {
+ kfree_sensitive(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);
+ kfree_sensitive(tmp);
+ return err;
+ }
+
+ /* Form a hex string of some last bytes as the key's hint */
+ bin2hex(tmp->hint, ukey->key + keylen - TIPC_AEAD_HINT_LEN,
+ TIPC_AEAD_HINT_LEN);
+
+ /* Initialize the other data */
+ tmp->mode = mode;
+ tmp->cloned = NULL;
+ tmp->authsize = TIPC_AES_GCM_TAG_SIZE;
+ tmp->key = kmemdup(ukey, tipc_aead_key_size(ukey), GFP_KERNEL);
+ if (!tmp->key) {
+ tipc_aead_free(&tmp->rcu);
+ return -ENOMEM;
+ }
+ 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)) {
+ kfree_sensitive(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.
+ */
+ SKB_LINEAR_ASSERT(skb);
+ if (tailen > skb_tailroom(skb)) {
+ pr_debug("TX(): skb tailroom is not enough: %d, requires: %d\n",
+ skb_tailroom(skb), tailen);
+ }
+
+ 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 ^= __be32_to_cpu(ehdr->addr);
+ 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]);
+ rcu_read_lock();
+ if (likely(test_bit(0, &b->up)))
+ b->media->send_msg(net, skb, b, &tx_ctx->dst);
+ else
+ kfree_skb(skb);
+ rcu_read_unlock();
+ 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;
+
+ 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 ^= __be32_to_cpu(ehdr->addr);
+ 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
+ *
+ * Return: "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;
+
+ 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->rx_nokey = (__rx) ? __rx->nokey : 0;
+ ehdr->master_key = aead->crypto->key_master;
+ 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)
+{
+ struct tipc_key old = c->key;
+ char buf[32];
+
+ c->key.keys = ((new_passive & KEY_MASK) << (KEY_BITS * 2)) |
+ ((new_active & KEY_MASK) << (KEY_BITS)) |
+ ((new_pending & KEY_MASK));
+
+ pr_debug("%s: key changing %s ::%pS\n", c->name,
+ tipc_key_change_dump(old, c->key, buf),
+ __builtin_return_address(0));
+}
+
+/**
+ * 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)
+ * @master_key: specify this is a cluster master 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, bool master_key)
+{
+ 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, master_key);
+ if (rc < 0)
+ tipc_aead_free(&aead->rcu);
+ }
+
+ 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!
+ * @master_key: specify this is a cluster master key
+ *
+ * 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,
+ bool master_key)
+{
+ struct tipc_key key;
+ int rc = -EBUSY;
+ u8 new_key;
+
+ spin_lock_bh(&c->lock);
+ key = c->key;
+ if (master_key) {
+ new_key = KEY_MASTER;
+ goto attach;
+ }
+ if (key.active && key.passive)
+ goto exit;
+ if (key.pending) {
+ if (tipc_aead_users(c->aead[key.pending]) > 0)
+ goto exit;
+ /* if (pos): ok with replacing, will be aligned when needed */
+ /* Replace it */
+ new_key = key.pending;
+ } else {
+ if (pos) {
+ if (key.active && pos != key_next(key.active)) {
+ key.passive = pos;
+ new_key = pos;
+ goto attach;
+ } else if (!key.active && !key.passive) {
+ key.pending = pos;
+ new_key = pos;
+ goto attach;
+ }
+ }
+ key.pending = key_next(key.active ?: key.passive);
+ new_key = key.pending;
+ }
+
+attach:
+ aead->crypto = c;
+ aead->gen = (is_tx(c)) ? ++c->key_gen : c->key_gen;
+ tipc_aead_rcu_replace(c->aead[new_key], aead, &c->lock);
+ if (likely(c->key.keys != key.keys))
+ tipc_crypto_key_set_state(c, key.passive, key.active,
+ key.pending);
+ c->working = 1;
+ c->nokey = 0;
+ c->key_master |= master_key;
+ rc = new_key;
+
+exit:
+ spin_unlock_bh(&c->lock);
+ return rc;
+}
+
+void tipc_crypto_key_flush(struct tipc_crypto *c)
+{
+ struct tipc_crypto *tx, *rx;
+ int k;
+
+ spin_lock_bh(&c->lock);
+ if (is_rx(c)) {
+ /* Try to cancel pending work */
+ rx = c;
+ tx = tipc_net(rx->net)->crypto_tx;
+ if (cancel_delayed_work(&rx->work)) {
+ kfree(rx->skey);
+ rx->skey = NULL;
+ atomic_xchg(&rx->key_distr, 0);
+ tipc_node_put(rx->node);
+ }
+ /* RX stopping => decrease TX key users if any */
+ k = atomic_xchg(&rx->peer_rx_active, 0);
+ if (k) {
+ tipc_aead_users_dec(tx->aead[k], 0);
+ /* Mark the point TX key users changed */
+ tx->timer1 = jiffies;
+ }
+ }
+
+ c->flags = 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);
+ 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) {
+ tmp2 = rcu_replace_pointer(rx->aead[key.passive], tmp2, lockdep_is_held(&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_ratelimited("%s: key[%d] -> key[%d]\n", rx->name, key.pending,
+ new_pending);
+
+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
+ * @tx_key: peer TX key id
+ *
+ * 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,
+ u8 tx_key)
+{
+ 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);
+ if (tx_key == KEY_MASTER) {
+ aead = tipc_aead_rcu_ptr(tx->aead[KEY_MASTER], &tx->lock);
+ goto done;
+ }
+ 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");
+ break;
+ } while (++i < 3);
+
+done:
+ if (likely(aead))
+ WARN_ON(!refcount_inc_not_zero(&aead->refcnt));
+ spin_unlock(&tx->lock);
+
+ return aead;
+}
+
+/**
+ * tipc_crypto_key_synch: Synch own key data according to peer key status
+ * @rx: RX crypto handle
+ * @skb: TIPCv2 message buffer (incl. the ehdr from peer)
+ *
+ * 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.
+ *
+ * It also considers if peer has no key, then we need to make own master key
+ * (if any) taking over i.e. starting grace period and also trigger key
+ * distributing process.
+ *
+ * The "per-peer" sndnxt is also reset when the peer key has switched.
+ */
+static void tipc_crypto_key_synch(struct tipc_crypto *rx, struct sk_buff *skb)
+{
+ struct tipc_ehdr *ehdr = (struct tipc_ehdr *)skb_network_header(skb);
+ struct tipc_crypto *tx = tipc_net(rx->net)->crypto_tx;
+ struct tipc_msg *hdr = buf_msg(skb);
+ u32 self = tipc_own_addr(rx->net);
+ u8 cur, new;
+ unsigned long delay;
+
+ /* Update RX 'key_master' flag according to peer, also mark "legacy" if
+ * a peer has no master key.
+ */
+ rx->key_master = ehdr->master_key;
+ if (!rx->key_master)
+ tx->legacy_user = 1;
+
+ /* For later cases, apply only if message is destined to this node */
+ if (!ehdr->destined || msg_short(hdr) || msg_destnode(hdr) != self)
+ return;
+
+ /* Case 1: Peer has no keys, let's make master key take over */
+ if (ehdr->rx_nokey) {
+ /* Set or extend grace period */
+ tx->timer2 = jiffies;
+ /* Schedule key distributing for the peer if not yet */
+ if (tx->key.keys &&
+ !atomic_cmpxchg(&rx->key_distr, 0, KEY_DISTR_SCHED)) {
+ get_random_bytes(&delay, 2);
+ delay %= 5;
+ delay = msecs_to_jiffies(500 * ++delay);
+ if (queue_delayed_work(tx->wq, &rx->work, delay))
+ tipc_node_get(rx->node);
+ }
+ } else {
+ /* Cancel a pending key distributing if any */
+ atomic_xchg(&rx->key_distr, 0);
+ }
+
+ /* Case 2: Peer RX active key has changed, let's update own TX users */
+ cur = atomic_read(&rx->peer_rx_active);
+ new = ehdr->rx_key_active;
+ if (tx->key.keys &&
+ cur != new &&
+ atomic_cmpxchg(&rx->peer_rx_active, cur, new) == cur) {
+ if (new)
+ tipc_aead_users_inc(tx->aead[new], INT_MAX);
+ if (cur)
+ tipc_aead_users_dec(tx->aead[cur], 0);
+
+ atomic64_set(&rx->sndnxt, 0);
+ /* Mark the point TX key users changed */
+ tx->timer1 = jiffies;
+
+ pr_debug("%s: key users changed %d-- %d++, peer %s\n",
+ tx->name, cur, new, rx->name);
+ }
+}
+
+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_bh(&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_bh(&tx->lock);
+
+ pr_warn("%s: key is revoked\n", tx->name);
+ 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 workqueue on TX */
+ if (!node) {
+ c->wq = alloc_ordered_workqueue("tipc_crypto", 0);
+ if (!c->wq) {
+ kfree(c);
+ return -ENOMEM;
+ }
+ }
+
+ /* Allocate statistic structure */
+ c->stats = alloc_percpu_gfp(struct tipc_crypto_stats, GFP_ATOMIC);
+ if (!c->stats) {
+ if (c->wq)
+ destroy_workqueue(c->wq);
+ kfree_sensitive(c);
+ return -ENOMEM;
+ }
+
+ c->flags = 0;
+ c->net = net;
+ c->node = node;
+ get_random_bytes(&c->key_gen, 2);
+ tipc_crypto_key_set_state(c, 0, 0, 0);
+ atomic_set(&c->key_distr, 0);
+ atomic_set(&c->peer_rx_active, 0);
+ atomic64_set(&c->sndnxt, 0);
+ c->timer1 = jiffies;
+ c->timer2 = jiffies;
+ c->rekeying_intv = TIPC_REKEYING_INTV_DEF;
+ spin_lock_init(&c->lock);
+ scnprintf(c->name, 48, "%s(%s)", (is_rx(c)) ? "RX" : "TX",
+ (is_rx(c)) ? tipc_node_get_id_str(c->node) :
+ tipc_own_id_string(c->net));
+
+ if (is_rx(c))
+ INIT_DELAYED_WORK(&c->work, tipc_crypto_work_rx);
+ else
+ INIT_DELAYED_WORK(&c->work, tipc_crypto_work_tx);
+
+ *crypto = c;
+ return 0;
+}
+
+void tipc_crypto_stop(struct tipc_crypto **crypto)
+{
+ struct tipc_crypto *c = *crypto;
+ u8 k;
+
+ if (!c)
+ return;
+
+ /* Flush any queued works & destroy wq */
+ if (is_tx(c)) {
+ c->rekeying_intv = 0;
+ cancel_delayed_work_sync(&c->work);
+ destroy_workqueue(c->wq);
+ }
+
+ /* Release AEAD keys */
+ rcu_read_lock();
+ for (k = KEY_MIN; k <= KEY_MAX; k++)
+ tipc_aead_put(rcu_dereference(c->aead[k]));
+ rcu_read_unlock();
+ pr_debug("%s: has been stopped\n", c->name);
+
+ /* Free this crypto statistics */
+ free_percpu(c->stats);
+
+ *crypto = NULL;
+ kfree_sensitive(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;
+ int cmd;
+
+ /* TX pending: taking all users & stable -> active */
+ 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_TIME))
+ 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("%s: key[%d] is activated\n", tx->name, key.pending);
+
+s1:
+ spin_unlock(&tx->lock);
+
+ /* RX pending: having user -> active */
+ spin_lock(&rx->lock);
+ key = rx->key;
+ if (!key.pending || tipc_aead_users(rx->aead[key.pending]) <= 0)
+ goto s2;
+
+ if (key.active)
+ key.passive = key.active;
+ key.active = key.pending;
+ rx->timer2 = jiffies;
+ tipc_crypto_key_set_state(rx, key.passive, key.active, 0);
+ this_cpu_inc(rx->stats->stat[STAT_SWITCHES]);
+ pr_info("%s: key[%d] is activated\n", rx->name, key.pending);
+ goto s5;
+
+s2:
+ /* RX pending: not working -> remove */
+ if (!key.pending || tipc_aead_users(rx->aead[key.pending]) > -10)
+ goto s3;
+
+ tipc_crypto_key_set_state(rx, key.passive, key.active, 0);
+ tipc_crypto_key_detach(rx->aead[key.pending], &rx->lock);
+ pr_debug("%s: key[%d] is removed\n", rx->name, key.pending);
+ goto s5;
+
+s3:
+ /* RX active: timed out or no user -> pending */
+ if (!key.active)
+ goto s4;
+ if (time_before(jiffies, rx->timer1 + TIPC_RX_ACTIVE_LIM) &&
+ tipc_aead_users(rx->aead[key.active]) > 0)
+ goto s4;
+
+ if (key.pending)
+ key.passive = key.active;
+ else
+ key.pending = key.active;
+ rx->timer2 = jiffies;
+ tipc_crypto_key_set_state(rx, key.passive, 0, key.pending);
+ tipc_aead_users_set(rx->aead[key.pending], 0);
+ pr_debug("%s: key[%d] is deactivated\n", rx->name, key.active);
+ goto s5;
+
+s4:
+ /* RX passive: outdated or not working -> free */
+ if (!key.passive)
+ goto s5;
+ if (time_before(jiffies, rx->timer2 + TIPC_RX_PASSIVE_LIM) &&
+ tipc_aead_users(rx->aead[key.passive]) > -10)
+ goto s5;
+
+ tipc_crypto_key_set_state(rx, 0, key.active, key.pending);
+ tipc_crypto_key_detach(rx->aead[key.passive], &rx->lock);
+ pr_debug("%s: key[%d] is freed\n", rx->name, key.passive);
+
+s5:
+ spin_unlock(&rx->lock);
+
+ /* Relax it here, the flag will be set again if it really is, but only
+ * when we are not in grace period for safety!
+ */
+ if (time_after(jiffies, tx->timer2 + TIPC_TX_GRACE_PERIOD))
+ tx->legacy_user = 0;
+
+ /* 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);
+}
+
+static inline void tipc_crypto_clone_msg(struct net *net, struct sk_buff *_skb,
+ struct tipc_bearer *b,
+ struct tipc_media_addr *dst,
+ struct tipc_node *__dnode, u8 type)
+{
+ struct sk_buff *skb;
+
+ skb = skb_clone(_skb, GFP_ATOMIC);
+ if (skb) {
+ TIPC_SKB_CB(skb)->xmit_type = type;
+ tipc_crypto_xmit(net, &skb, b, dst, __dnode);
+ if (skb)
+ b->media->send_msg(net, skb, b, dst);
+ }
+}
+
+/**
+ * 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 pending, master or active
+ * key with this preference order.
+ * 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_msg *hdr = buf_msg(*skb);
+ struct tipc_key key = tx->key;
+ struct tipc_aead *aead = NULL;
+ u32 user = msg_user(hdr);
+ u32 type = msg_type(hdr);
+ int rc = -ENOKEY;
+ u8 tx_key = 0;
+
+ /* No encryption? */
+ if (!tx->working)
+ return 0;
+
+ /* Pending key if peer has active on it or probing time */
+ if (unlikely(key.pending)) {
+ tx_key = key.pending;
+ if (!tx->key_master && !key.active)
+ goto encrypt;
+ if (__rx && atomic_read(&__rx->peer_rx_active) == tx_key)
+ goto encrypt;
+ if (TIPC_SKB_CB(*skb)->xmit_type == SKB_PROBING) {
+ pr_debug("%s: probing for key[%d]\n", tx->name,
+ key.pending);
+ goto encrypt;
+ }
+ if (user == LINK_CONFIG || user == LINK_PROTOCOL)
+ tipc_crypto_clone_msg(net, *skb, b, dst, __dnode,
+ SKB_PROBING);
+ }
+
+ /* Master key if this is a *vital* message or in grace period */
+ if (tx->key_master) {
+ tx_key = KEY_MASTER;
+ if (!key.active)
+ goto encrypt;
+ if (TIPC_SKB_CB(*skb)->xmit_type == SKB_GRACING) {
+ pr_debug("%s: gracing for msg (%d %d)\n", tx->name,
+ user, type);
+ goto encrypt;
+ }
+ if (user == LINK_CONFIG ||
+ (user == LINK_PROTOCOL && type == RESET_MSG) ||
+ (user == MSG_CRYPTO && type == KEY_DISTR_MSG) ||
+ time_before(jiffies, tx->timer2 + TIPC_TX_GRACE_PERIOD)) {
+ if (__rx && __rx->key_master &&
+ !atomic_read(&__rx->peer_rx_active))
+ goto encrypt;
+ if (!__rx) {
+ if (likely(!tx->legacy_user))
+ goto encrypt;
+ tipc_crypto_clone_msg(net, *skb, b, dst,
+ __dnode, SKB_GRACING);
+ }
+ }
+ }
+
+ /* 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, n;
+
+ tx_key = ((struct tipc_ehdr *)(*skb)->data)->tx_key;
+
+ /* New peer?
+ * Let's try with TX key (i.e. cluster mode) & verify the skb first!
+ */
+ if (unlikely(!rx || tx_key == KEY_MASTER))
+ goto pick_tx;
+
+ /* Pick RX key according to TX key if any */
+ key = rx->key;
+ if (tx_key == key.active || tx_key == key.pending ||
+ tx_key == key.passive)
+ 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, tx_key);
+ 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) {
+ /* Mark rx->nokey only if we dont have a
+ * pending received session key, nor a newer
+ * one i.e. in the next slot.
+ */
+ n = key_next(tx_key);
+ rx->nokey = !(rx->skey ||
+ rcu_access_pointer(rx->aead[n]));
+ pr_debug_ratelimited("%s: nokey %d, key %d/%x\n",
+ rx->name, rx->nokey,
+ tx_key, rx->key.keys);
+ 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;
+
+ /* Is this completed by TX? */
+ if (unlikely(is_tx(aead->crypto))) {
+ rx = skb_cb->tx_clone_ctx.rx;
+ pr_debug("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_debug("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]);
+ 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;
+ }
+
+ /* Ignore cloning if it was TX master key */
+ if (ehdr->tx_key == KEY_MASTER)
+ goto rcv;
+ if (tipc_aead_clone(&tmp, aead) < 0)
+ goto rcv;
+ WARN_ON(!refcount_inc_not_zero(&tmp->refcnt));
+ if (tipc_crypto_key_attach(rx, tmp, ehdr->tx_key, false) < 0) {
+ tipc_aead_free(&tmp->rcu);
+ goto rcv;
+ }
+ tipc_aead_put(aead);
+ aead = tmp;
+ }
+
+ if (unlikely(err)) {
+ tipc_aead_users_dec((struct tipc_aead __force __rcu *)aead, INT_MIN);
+ goto free_skb;
+ }
+
+ /* Set the RX key's user */
+ tipc_aead_users_set((struct tipc_aead __force __rcu *)aead, 1);
+
+ /* Mark this point, RX works */
+ rx->timer1 = jiffies;
+
+rcv:
+ /* Remove ehdr & auth. tag prior to tipc_rcv() */
+ ehdr = (struct tipc_ehdr *)(*skb)->data;
+
+ /* Mark this point, RX passive still works */
+ if (rx->key.passive && ehdr->tx_key == rx->key.passive)
+ rx->timer2 = jiffies;
+
+ skb_reset_network_header(*skb);
+ skb_pull(*skb, tipc_ehdr_size(ehdr));
+ if (pskb_trim(*skb, (*skb)->len - aead->authsize))
+ goto free_skb;
+
+ /* Validate TIPCv2 message */
+ if (unlikely(!tipc_msg_validate(skb))) {
+ pr_err_ratelimited("Packet dropped after decryption!\n");
+ goto free_skb;
+ }
+
+ /* Ok, everything's fine, try to synch own keys according to peers' */
+ tipc_crypto_key_synch(rx, *skb);
+
+ /* Re-fetch skb cb as skb might be changed in tipc_msg_validate */
+ skb_cb = TIPC_SKB_CB(*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("Counter %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_MASTER) {
+ if (is_rx(c))
+ continue;
+ if (time_before(jiffies,
+ c->timer2 + TIPC_TX_GRACE_PERIOD))
+ s = "ACT";
+ else
+ s = "PAS";
+ } else {
+ 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,
+ "{\"0x...%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 (is_rx(c))
+ i += scnprintf(buf + i, 200 - i, "\tPeer RX active: %d\n",
+ atomic_read(&c->peer_rx_active));
+
+ return buf;
+}
+
+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_1; k <= KEY_3; 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_3) ? "%s " : "%s", s);
+ }
+ if (key != &new) {
+ i += scnprintf(buf + i, 32 - i, "] -> ");
+ key = &new;
+ goto again;
+ }
+ i += scnprintf(buf + i, 32 - i, "]");
+ return buf;
+}
+
+/**
+ * tipc_crypto_msg_rcv - Common 'MSG_CRYPTO' processing point
+ * @net: the struct net
+ * @skb: the receiving message buffer
+ */
+void tipc_crypto_msg_rcv(struct net *net, struct sk_buff *skb)
+{
+ struct tipc_crypto *rx;
+ struct tipc_msg *hdr;
+
+ if (unlikely(skb_linearize(skb)))
+ goto exit;
+
+ hdr = buf_msg(skb);
+ rx = tipc_node_crypto_rx_by_addr(net, msg_prevnode(hdr));
+ if (unlikely(!rx))
+ goto exit;
+
+ switch (msg_type(hdr)) {
+ case KEY_DISTR_MSG:
+ if (tipc_crypto_key_rcv(rx, hdr))
+ goto exit;
+ break;
+ default:
+ break;
+ }
+
+ tipc_node_put(rx->node);
+
+exit:
+ kfree_skb(skb);
+}
+
+/**
+ * tipc_crypto_key_distr - Distribute a TX key
+ * @tx: the TX crypto
+ * @key: the key's index
+ * @dest: the destination tipc node, = NULL if distributing to all nodes
+ *
+ * Return: 0 in case of success, otherwise < 0
+ */
+int tipc_crypto_key_distr(struct tipc_crypto *tx, u8 key,
+ struct tipc_node *dest)
+{
+ struct tipc_aead *aead;
+ u32 dnode = tipc_node_get_addr(dest);
+ int rc = -ENOKEY;
+
+ if (!sysctl_tipc_key_exchange_enabled)
+ return 0;
+
+ if (key) {
+ rcu_read_lock();
+ aead = tipc_aead_get(tx->aead[key]);
+ if (likely(aead)) {
+ rc = tipc_crypto_key_xmit(tx->net, aead->key,
+ aead->gen, aead->mode,
+ dnode);
+ tipc_aead_put(aead);
+ }
+ rcu_read_unlock();
+ }
+
+ return rc;
+}
+
+/**
+ * tipc_crypto_key_xmit - Send a session key
+ * @net: the struct net
+ * @skey: the session key to be sent
+ * @gen: the key's generation
+ * @mode: the key's mode
+ * @dnode: the destination node address, = 0 if broadcasting to all nodes
+ *
+ * The session key 'skey' is packed in a TIPC v2 'MSG_CRYPTO/KEY_DISTR_MSG'
+ * as its data section, then xmit-ed through the uc/bc link.
+ *
+ * Return: 0 in case of success, otherwise < 0
+ */
+static int tipc_crypto_key_xmit(struct net *net, struct tipc_aead_key *skey,
+ u16 gen, u8 mode, u32 dnode)
+{
+ struct sk_buff_head pkts;
+ struct tipc_msg *hdr;
+ struct sk_buff *skb;
+ u16 size, cong_link_cnt;
+ u8 *data;
+ int rc;
+
+ size = tipc_aead_key_size(skey);
+ skb = tipc_buf_acquire(INT_H_SIZE + size, GFP_ATOMIC);
+ if (!skb)
+ return -ENOMEM;
+
+ hdr = buf_msg(skb);
+ tipc_msg_init(tipc_own_addr(net), hdr, MSG_CRYPTO, KEY_DISTR_MSG,
+ INT_H_SIZE, dnode);
+ msg_set_size(hdr, INT_H_SIZE + size);
+ msg_set_key_gen(hdr, gen);
+ msg_set_key_mode(hdr, mode);
+
+ data = msg_data(hdr);
+ *((__be32 *)(data + TIPC_AEAD_ALG_NAME)) = htonl(skey->keylen);
+ memcpy(data, skey->alg_name, TIPC_AEAD_ALG_NAME);
+ memcpy(data + TIPC_AEAD_ALG_NAME + sizeof(__be32), skey->key,
+ skey->keylen);
+
+ __skb_queue_head_init(&pkts);
+ __skb_queue_tail(&pkts, skb);
+ if (dnode)
+ rc = tipc_node_xmit(net, &pkts, dnode, 0);
+ else
+ rc = tipc_bcast_xmit(net, &pkts, &cong_link_cnt);
+
+ return rc;
+}
+
+/**
+ * tipc_crypto_key_rcv - Receive a session key
+ * @rx: the RX crypto
+ * @hdr: the TIPC v2 message incl. the receiving session key in its data
+ *
+ * This function retrieves the session key in the message from peer, then
+ * schedules a RX work to attach the key to the corresponding RX crypto.
+ *
+ * Return: "true" if the key has been scheduled for attaching, otherwise
+ * "false".
+ */
+static bool tipc_crypto_key_rcv(struct tipc_crypto *rx, struct tipc_msg *hdr)
+{
+ struct tipc_crypto *tx = tipc_net(rx->net)->crypto_tx;
+ struct tipc_aead_key *skey = NULL;
+ u16 key_gen = msg_key_gen(hdr);
+ u32 size = msg_data_sz(hdr);
+ u8 *data = msg_data(hdr);
+ unsigned int keylen;
+
+ /* Verify whether the size can exist in the packet */
+ if (unlikely(size < sizeof(struct tipc_aead_key) + TIPC_AEAD_KEYLEN_MIN)) {
+ pr_debug("%s: message data size is too small\n", rx->name);
+ goto exit;
+ }
+
+ keylen = ntohl(*((__be32 *)(data + TIPC_AEAD_ALG_NAME)));
+
+ /* Verify the supplied size values */
+ if (unlikely(size != keylen + sizeof(struct tipc_aead_key) ||
+ keylen > TIPC_AEAD_KEY_SIZE_MAX)) {
+ pr_debug("%s: invalid MSG_CRYPTO key size\n", rx->name);
+ goto exit;
+ }
+
+ spin_lock(&rx->lock);
+ if (unlikely(rx->skey || (key_gen == rx->key_gen && rx->key.keys))) {
+ pr_err("%s: key existed <%p>, gen %d vs %d\n", rx->name,
+ rx->skey, key_gen, rx->key_gen);
+ goto exit_unlock;
+ }
+
+ /* Allocate memory for the key */
+ skey = kmalloc(size, GFP_ATOMIC);
+ if (unlikely(!skey)) {
+ pr_err("%s: unable to allocate memory for skey\n", rx->name);
+ goto exit_unlock;
+ }
+
+ /* Copy key from msg data */
+ skey->keylen = keylen;
+ memcpy(skey->alg_name, data, TIPC_AEAD_ALG_NAME);
+ memcpy(skey->key, data + TIPC_AEAD_ALG_NAME + sizeof(__be32),
+ skey->keylen);
+
+ rx->key_gen = key_gen;
+ rx->skey_mode = msg_key_mode(hdr);
+ rx->skey = skey;
+ rx->nokey = 0;
+ mb(); /* for nokey flag */
+
+exit_unlock:
+ spin_unlock(&rx->lock);
+
+exit:
+ /* Schedule the key attaching on this crypto */
+ if (likely(skey && queue_delayed_work(tx->wq, &rx->work, 0)))
+ return true;
+
+ return false;
+}
+
+/**
+ * tipc_crypto_work_rx - Scheduled RX works handler
+ * @work: the struct RX work
+ *
+ * The function processes the previous scheduled works i.e. distributing TX key
+ * or attaching a received session key on RX crypto.
+ */
+static void tipc_crypto_work_rx(struct work_struct *work)
+{
+ struct delayed_work *dwork = to_delayed_work(work);
+ struct tipc_crypto *rx = container_of(dwork, struct tipc_crypto, work);
+ struct tipc_crypto *tx = tipc_net(rx->net)->crypto_tx;
+ unsigned long delay = msecs_to_jiffies(5000);
+ bool resched = false;
+ u8 key;
+ int rc;
+
+ /* Case 1: Distribute TX key to peer if scheduled */
+ if (atomic_cmpxchg(&rx->key_distr,
+ KEY_DISTR_SCHED,
+ KEY_DISTR_COMPL) == KEY_DISTR_SCHED) {
+ /* Always pick the newest one for distributing */
+ key = tx->key.pending ?: tx->key.active;
+ rc = tipc_crypto_key_distr(tx, key, rx->node);
+ if (unlikely(rc))
+ pr_warn("%s: unable to distr key[%d] to %s, err %d\n",
+ tx->name, key, tipc_node_get_id_str(rx->node),
+ rc);
+
+ /* Sched for key_distr releasing */
+ resched = true;
+ } else {
+ atomic_cmpxchg(&rx->key_distr, KEY_DISTR_COMPL, 0);
+ }
+
+ /* Case 2: Attach a pending received session key from peer if any */
+ if (rx->skey) {
+ rc = tipc_crypto_key_init(rx, rx->skey, rx->skey_mode, false);
+ if (unlikely(rc < 0))
+ pr_warn("%s: unable to attach received skey, err %d\n",
+ rx->name, rc);
+ switch (rc) {
+ case -EBUSY:
+ case -ENOMEM:
+ /* Resched the key attaching */
+ resched = true;
+ break;
+ default:
+ synchronize_rcu();
+ kfree(rx->skey);
+ rx->skey = NULL;
+ break;
+ }
+ }
+
+ if (resched && queue_delayed_work(tx->wq, &rx->work, delay))
+ return;
+
+ tipc_node_put(rx->node);
+}
+
+/**
+ * tipc_crypto_rekeying_sched - (Re)schedule rekeying w/o new interval
+ * @tx: TX crypto
+ * @changed: if the rekeying needs to be rescheduled with new interval
+ * @new_intv: new rekeying interval (when "changed" = true)
+ */
+void tipc_crypto_rekeying_sched(struct tipc_crypto *tx, bool changed,
+ u32 new_intv)
+{
+ unsigned long delay;
+ bool now = false;
+
+ if (changed) {
+ if (new_intv == TIPC_REKEYING_NOW)
+ now = true;
+ else
+ tx->rekeying_intv = new_intv;
+ cancel_delayed_work_sync(&tx->work);
+ }
+
+ if (tx->rekeying_intv || now) {
+ delay = (now) ? 0 : tx->rekeying_intv * 60 * 1000;
+ queue_delayed_work(tx->wq, &tx->work, msecs_to_jiffies(delay));
+ }
+}
+
+/**
+ * tipc_crypto_work_tx - Scheduled TX works handler
+ * @work: the struct TX work
+ *
+ * The function processes the previous scheduled work, i.e. key rekeying, by
+ * generating a new session key based on current one, then attaching it to the
+ * TX crypto and finally distributing it to peers. It also re-schedules the
+ * rekeying if needed.
+ */
+static void tipc_crypto_work_tx(struct work_struct *work)
+{
+ struct delayed_work *dwork = to_delayed_work(work);
+ struct tipc_crypto *tx = container_of(dwork, struct tipc_crypto, work);
+ struct tipc_aead_key *skey = NULL;
+ struct tipc_key key = tx->key;
+ struct tipc_aead *aead;
+ int rc = -ENOMEM;
+
+ if (unlikely(key.pending))
+ goto resched;
+
+ /* Take current key as a template */
+ rcu_read_lock();
+ aead = rcu_dereference(tx->aead[key.active ?: KEY_MASTER]);
+ if (unlikely(!aead)) {
+ rcu_read_unlock();
+ /* At least one key should exist for securing */
+ return;
+ }
+
+ /* Lets duplicate it first */
+ skey = kmemdup(aead->key, tipc_aead_key_size(aead->key), GFP_ATOMIC);
+ rcu_read_unlock();
+
+ /* Now, generate new key, initiate & distribute it */
+ if (likely(skey)) {
+ rc = tipc_aead_key_generate(skey) ?:
+ tipc_crypto_key_init(tx, skey, PER_NODE_KEY, false);
+ if (likely(rc > 0))
+ rc = tipc_crypto_key_distr(tx, rc, NULL);
+ kfree_sensitive(skey);
+ }
+
+ if (unlikely(rc))
+ pr_warn_ratelimited("%s: rekeying returns %d\n", tx->name, rc);
+
+resched:
+ /* Re-schedule rekeying if any */
+ tipc_crypto_rekeying_sched(tx, false, 0);
+}