diff options
Diffstat (limited to 'net/tipc/crypto.c')
| -rw-r--r-- | net/tipc/crypto.c | 981 |
1 files changed, 727 insertions, 254 deletions
diff --git a/net/tipc/crypto.c b/net/tipc/crypto.c index 7c523dc81575..40c44101fe8e 100644 --- a/net/tipc/crypto.c +++ b/net/tipc/crypto.c @@ -36,22 +36,28 @@ #include <crypto/aead.h> #include <crypto/aes.h> +#include <crypto/rng.h> #include "crypto.h" +#include "msg.h" +#include "bcast.h" -#define TIPC_TX_PROBE_LIM msecs_to_jiffies(1000) /* > 1s */ -#define TIPC_TX_LASTING_LIM msecs_to_jiffies(120000) /* 2 mins */ +#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(180000) /* 3 mins */ +#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_UNUSED = 0, - KEY_MIN, - KEY_1 = KEY_MIN, + KEY_MASTER = 0, + KEY_MIN = KEY_MASTER, + KEY_1 = 1, KEY_2, KEY_3, KEY_MAX = KEY_3, @@ -81,6 +87,8 @@ static const char *hstats[MAX_STATS] = {"ok", "nok", "async", "async_ok", /* 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 @@ -132,6 +140,8 @@ struct tipc_tfm { * @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 */ @@ -144,8 +154,10 @@ struct tipc_aead { u32 salt; u8 authsize; u8 mode; - char hint[TIPC_AEAD_HINT_LEN + 1]; + 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; @@ -165,26 +177,56 @@ struct tipc_crypto_stats { * @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 - * @working: the crypto is working or not + * @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 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 * @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 */ + struct tipc_aead __rcu *aead[KEY_MAX + 1]; atomic_t peer_rx_active; + u16 key_gen; struct tipc_key key; - u8 working:1; + 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; @@ -234,23 +276,35 @@ static inline void tipc_crypto_key_set_state(struct tipc_crypto *c, u8 new_active, u8 new_pending); static int tipc_crypto_key_attach(struct tipc_crypto *c, - struct tipc_aead *aead, u8 pos); + 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); -static void tipc_crypto_key_synch(struct tipc_crypto *rx, u8 new_rx_active, - struct tipc_msg *hdr); + 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); -#ifdef TIPC_CRYPTO_DEBUG static char *tipc_key_change_dump(struct tipc_key old, struct tipc_key new, char *buf); -#endif +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) @@ -271,30 +325,55 @@ do { \ /** * tipc_aead_key_validate - Validate a AEAD user key */ -int tipc_aead_key_validate(struct tipc_aead_key *ukey) +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))) { - pr_info("Not found cipher: \"%s\"!\n", ukey->alg_name); + 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)")) + 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)) - return -EINVAL; + 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; @@ -339,6 +418,7 @@ static void tipc_aead_free(struct rcu_head *rp) kfree(head); } free_percpu(aead->tfm_entry); + kzfree(aead->key); kfree(aead); } @@ -501,14 +581,15 @@ static int tipc_aead_init(struct tipc_aead **aead, struct tipc_aead_key *ukey, 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'; + /* 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); memcpy(&tmp->salt, ukey->key + keylen, TIPC_AES_GCM_SALT_SIZE); atomic_set(&tmp->users, 0); atomic64_set(&tmp->seqno, 0); @@ -663,13 +744,11 @@ static int tipc_aead_encrypt(struct tipc_aead *aead, struct sk_buff *skb, * 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); + pr_debug("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; @@ -940,8 +1019,6 @@ bool tipc_ehdr_validate(struct sk_buff *skb) return false; if (unlikely(skb->len <= ehsz + TIPC_AES_GCM_TAG_SIZE)) return false; - if (unlikely(!ehdr->tx_key)) - return false; return true; } @@ -994,6 +1071,8 @@ static int tipc_ehdr_build(struct net *net, struct tipc_aead *aead, 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; @@ -1019,23 +1098,16 @@ static inline void tipc_crypto_key_set_state(struct tipc_crypto *c, 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 + pr_debug("%s: key changing %s ::%pS\n", c->name, + tipc_key_change_dump(old, c->key, buf), + __builtin_return_address(0)); } /** @@ -1043,6 +1115,7 @@ static inline void tipc_crypto_key_set_state(struct tipc_crypto *c, * @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. @@ -1050,7 +1123,7 @@ static inline void tipc_crypto_key_set_state(struct tipc_crypto *c, * 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) + u8 mode, bool master_key) { struct tipc_aead *aead = NULL; int rc = 0; @@ -1060,17 +1133,11 @@ int tipc_crypto_key_init(struct tipc_crypto *c, struct tipc_aead_key *ukey, /* Attach it to the crypto */ if (likely(!rc)) { - rc = tipc_crypto_key_attach(c, aead, 0); + rc = tipc_crypto_key_attach(c, aead, 0, master_key); 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; } @@ -1079,58 +1146,58 @@ int tipc_crypto_key_init(struct tipc_crypto *c, struct tipc_aead_key *ukey, * @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) + struct tipc_aead *aead, u8 pos, + bool master_key) { - u8 new_pending, new_passive, new_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.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; + /* if (pos): ok with replacing, will be aligned when needed */ /* Replace it */ - new_pending = key.pending; - new_passive = key.passive; - new_key = new_pending; + new_key = key.pending; } else { if (pos) { if (key.active && pos != key_next(key.active)) { - new_pending = key.pending; - new_passive = pos; - new_key = new_passive; + key.passive = pos; + new_key = pos; goto attach; } else if (!key.active && !key.passive) { - new_pending = pos; - new_passive = key.passive; - new_key = new_pending; + key.pending = pos; + new_key = pos; goto attach; } } - new_pending = key_next(key.active ?: key.passive); - new_passive = key.passive; - new_key = new_pending; + key.pending = key_next(key.active ?: key.passive); + new_key = key.pending; } attach: aead->crypto = c; - tipc_crypto_key_set_state(c, new_passive, key.active, new_pending); + 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->timer1 = jiffies; - c->timer2 = jiffies; + c->nokey = 0; + c->key_master |= master_key; rc = new_key; exit: @@ -1140,14 +1207,33 @@ exit: void tipc_crypto_key_flush(struct tipc_crypto *c) { + struct tipc_crypto *tx, *rx; int k; spin_lock_bh(&c->lock); - c->working = 0; + 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); - atomic_set(&c->peer_rx_active, 0); atomic64_set(&c->sndnxt, 0); spin_unlock_bh(&c->lock); } @@ -1206,7 +1292,8 @@ static bool tipc_crypto_key_try_align(struct tipc_crypto *rx, u8 new_pending) 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)); + pr_info_ratelimited("%s: key[%d] -> key[%d]\n", rx->name, key.pending, + new_pending); exit: spin_unlock(&rx->lock); @@ -1218,6 +1305,7 @@ exit: * @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 @@ -1227,7 +1315,8 @@ exit: */ static struct tipc_aead *tipc_crypto_key_pick_tx(struct tipc_crypto *tx, struct tipc_crypto *rx, - struct sk_buff *skb) + struct sk_buff *skb, + u8 tx_key) { struct tipc_skb_cb *skb_cb = TIPC_SKB_CB(skb); struct tipc_aead *aead = NULL; @@ -1246,6 +1335,10 @@ static struct tipc_aead *tipc_crypto_key_pick_tx(struct tipc_crypto *tx, /* 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); @@ -1265,9 +1358,12 @@ static struct tipc_aead *tipc_crypto_key_pick_tx(struct tipc_crypto *tx, 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); + +done: + if (likely(aead)) + WARN_ON(!refcount_inc_not_zero(&aead->refcnt)); spin_unlock(&tx->lock); return aead; @@ -1276,53 +1372,73 @@ static struct tipc_aead *tipc_crypto_key_pick_tx(struct tipc_crypto *tx, /** * 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 + * @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, u8 new_rx_active, - struct tipc_msg *hdr) +static void tipc_crypto_key_synch(struct tipc_crypto *rx, struct sk_buff *skb) { - struct net *net = rx->net; - struct tipc_crypto *tx = tipc_net(net)->crypto_tx; - u8 cur_rx_active; + 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; - /* TX might be even not ready yet */ - if (unlikely(!tx->key.active && !tx->key.pending)) - return; + /* 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; - cur_rx_active = atomic_read(&rx->peer_rx_active); - if (likely(cur_rx_active == new_rx_active)) + /* For later cases, apply only if message is destined to this node */ + if (!ehdr->destined || msg_short(hdr) || msg_destnode(hdr) != self) return; - /* Make sure this message destined for this node */ - if (unlikely(msg_short(hdr) || - msg_destnode(hdr) != tipc_own_addr(net))) - 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); + } - /* 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); + /* 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; -#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 + pr_debug("%s: key users changed %d-- %d++, peer %s\n", + tx->name, cur, new, rx->name); } } @@ -1340,7 +1456,7 @@ static int tipc_crypto_key_revoke(struct net *net, u8 tx_key) 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)); + pr_warn("%s: key is revoked\n", tx->name); return -EKEYREVOKED; } @@ -1357,6 +1473,15 @@ int tipc_crypto_start(struct tipc_crypto **crypto, struct net *net, 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) { @@ -1364,53 +1489,52 @@ int tipc_crypto_start(struct tipc_crypto **crypto, struct net *net, return -ENOMEM; } - c->working = 0; + 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); - *crypto = c; + 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, *tx, *rx; - bool is_rx; + struct tipc_crypto *c = *crypto; u8 k; - if (!*crypto) + if (!c) 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; - } + /* 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 */ - c = *crypto; + rcu_read_lock(); 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)); + pr_debug("%s: has been stopped\n", c->name); /* Free this crypto statistics */ free_percpu(c->stats); @@ -1424,106 +1548,91 @@ 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 - */ + /* 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_LIM)) + 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("TX(%s): key %d is activated!\n", tipc_own_id_string(tx->net), - key.pending); + pr_info("%s: key[%d] is activated\n", tx->name, key.pending); s1: spin_unlock(&tx->lock); - /* RX key activating: - * The pending key (users > 0) -> active - * The active key if any -> passive, freed later - */ + /* 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; - 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); + 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("RX(%s): key %d is activated!\n", - tipc_node_get_id_str(rx->node), key.pending); + pr_info("%s: key[%d] is activated\n", rx->name, 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) + /* RX pending: not working -> remove */ + if (!key.pending || tipc_aead_users(rx->aead[key.pending]) > -10) goto s3; - new_pending = key.passive; - new_passive = key.pending; - tipc_crypto_key_set_state(rx, new_passive, key.active, new_pending); + 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 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; + /* RX active: timed out or no user -> pending */ if (!key.active) goto s4; - if (time_before(jiffies, rx->timer1 + TIPC_RX_ACTIVE_LIM)) + if (time_before(jiffies, rx->timer1 + TIPC_RX_ACTIVE_LIM) && + tipc_aead_users(rx->aead[key.active]) > 0) 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); + 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 key passive -> freed: */ - key = rx->key; - if (!key.passive || !tipc_aead_users(rx->aead[key.passive])) + /* RX passive: outdated or not working -> free */ + if (!key.passive) goto s5; - if (time_before(jiffies, rx->timer2 + TIPC_RX_PASSIVE_LIM)) + 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_info("RX(%s): key %d is freed!\n", tipc_node_get_id_str(rx->node), - key.passive); + 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; @@ -1533,6 +1642,22 @@ s5: 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 @@ -1542,7 +1667,8 @@ s5: * @__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. + * 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! @@ -1562,46 +1688,67 @@ int tipc_crypto_xmit(struct net *net, struct sk_buff **skb, 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; - struct sk_buff *probe; + u32 user = msg_user(hdr); + u32 type = msg_type(hdr); int rc = -ENOKEY; - u8 tx_key; + u8 tx_key = 0; /* 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; - */ + /* Pending key if peer has active on it or probing time */ if (unlikely(key.pending)) { tx_key = key.pending; - if (!key.active) + 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)->probe) + 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 (!__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); + } + 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: @@ -1667,30 +1814,21 @@ int tipc_crypto_rcv(struct net *net, struct tipc_crypto *rx, struct tipc_aead *aead = NULL; struct tipc_key key; int rc = -ENOKEY; - u8 tx_key = 0; + 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)) + if (unlikely(!rx || tx_key == KEY_MASTER)) 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; + /* Pick RX key according to TX key if any */ key = rx->key; - if (likely(tx_key == key.active)) + if (tx_key == key.active || tx_key == key.pending || + tx_key == key.passive) 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)) @@ -1698,7 +1836,7 @@ int tipc_crypto_rcv(struct net *net, struct tipc_crypto *rx, pick_tx: /* No key suitable? Try to pick one from TX... */ - aead = tipc_crypto_key_pick_tx(tx, rx, *skb); + aead = tipc_crypto_key_pick_tx(tx, rx, *skb, tx_key); if (aead) goto decrypt; goto exit; @@ -1726,8 +1864,19 @@ exit: if (rc == -ENOKEY) { kfree_skb(*skb); *skb = NULL; - if (rx) + 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) { @@ -1749,21 +1898,17 @@ static void tipc_crypto_rcv_complete(struct net *net, struct tipc_aead *aead, 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)) { + if (unlikely(is_tx(aead->crypto))) { 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 + 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); @@ -1784,12 +1929,12 @@ static void tipc_crypto_rcv_complete(struct net *net, struct tipc_aead *aead, goto free_skb; } - /* Skip cloning this time as we had a RX pending key */ - if (rx->key.pending) + /* 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; - if (tipc_crypto_key_attach(rx, tmp, ehdr->tx_key) < 0) { + if (tipc_crypto_key_attach(rx, tmp, ehdr->tx_key, false) < 0) { tipc_aead_free(&tmp->rcu); goto rcv; } @@ -1805,14 +1950,18 @@ static void tipc_crypto_rcv_complete(struct net *net, struct tipc_aead *aead, /* Set the RX key's user */ tipc_aead_users_set(aead, 1); -rcv: /* Mark this point, RX works */ rx->timer1 = jiffies; +rcv: /* Remove ehdr & auth. tag prior to tipc_rcv() */ ehdr = (struct tipc_ehdr *)(*skb)->data; - destined = ehdr->destined; - rx_key_active = ehdr->rx_key_active; + + /* 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)); pskb_trim(*skb, (*skb)->len - aead->authsize); @@ -1822,9 +1971,8 @@ rcv: goto free_skb; } - /* Update peer RX active key & TX users */ - if (destined) - tipc_crypto_key_synch(rx, rx_key_active, buf_msg(*skb)); + /* Ok, everything's fine, try to synch own keys according to peers' */ + tipc_crypto_key_synch(rx, *skb); /* Mark skb decrypted */ skb_cb->decrypted = 1; @@ -1883,7 +2031,7 @@ print_stats: /* 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); + pr_info("Counter %s", buf); memset(buf, '-', 115); buf[115] = '\0'; @@ -1927,21 +2075,31 @@ static char *tipc_crypto_key_dump(struct tipc_crypto *c, char *buf) 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 = "-"; + 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, - "{\"%s...\", \"%s\"}/%d:%d", + "{\"0x...%s\", \"%s\"}/%d:%d", aead->hint, (aead->mode == CLUSTER_KEY) ? "c" : "p", atomic_read(&aead->users), @@ -1950,14 +2108,13 @@ static char *tipc_crypto_key_dump(struct tipc_crypto *c, char *buf) i += scnprintf(buf + i, 200 - i, "\n"); } - if (c->node) + if (is_rx(c)) 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) { @@ -1968,7 +2125,7 @@ static char *tipc_key_change_dump(struct tipc_key old, struct tipc_key new, /* 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++) { + for (k = KEY_1; k <= KEY_3; k++) { if (k == key->passive) s = "pas"; else if (k == key->active) @@ -1978,7 +2135,7 @@ again: else s = "-"; i += scnprintf(buf + i, 32 - i, - (k != KEY_MAX) ? "%s " : "%s", s); + (k != KEY_3) ? "%s " : "%s", s); } if (key != &new) { i += scnprintf(buf + i, 32 - i, "] -> "); @@ -1988,4 +2145,320 @@ again: i += scnprintf(buf + i, 32 - i, "]"); return buf; } -#endif + +/** + * 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); + u16 size = msg_data_sz(hdr); + u8 *data = msg_data(hdr); + + 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; + } + + /* 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; + } + + /* Copy key from msg data */ + skey->keylen = ntohl(*((__be32 *)(data + TIPC_AEAD_ALG_NAME))); + memcpy(skey->alg_name, data, TIPC_AEAD_ALG_NAME); + memcpy(skey->key, data + TIPC_AEAD_ALG_NAME + sizeof(__be32), + skey->keylen); + + /* Sanity check */ + if (unlikely(size != tipc_aead_key_size(skey))) { + kfree(skey); + skey = NULL; + goto exit; + } + + rx->key_gen = key_gen; + rx->skey_mode = msg_key_mode(hdr); + rx->skey = skey; + rx->nokey = 0; + mb(); /* for nokey flag */ + +exit: + spin_unlock(&rx->lock); + + /* 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); + kzfree(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); +} |