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Diffstat (limited to 'src/plugins/wireguard/wireguard_noise.c')
-rw-r--r--src/plugins/wireguard/wireguard_noise.c174
1 files changed, 104 insertions, 70 deletions
diff --git a/src/plugins/wireguard/wireguard_noise.c b/src/plugins/wireguard/wireguard_noise.c
index 36de8ae9cac..c8605f117cd 100644
--- a/src/plugins/wireguard/wireguard_noise.c
+++ b/src/plugins/wireguard/wireguard_noise.c
@@ -36,7 +36,7 @@ static uint32_t noise_remote_handshake_index_get (noise_remote_t *);
static void noise_remote_handshake_index_drop (noise_remote_t *);
static uint64_t noise_counter_send (noise_counter_t *);
-static bool noise_counter_recv (noise_counter_t *, uint64_t);
+bool noise_counter_recv (noise_counter_t *, uint64_t);
static void noise_kdf (uint8_t *, uint8_t *, uint8_t *, const uint8_t *,
size_t, size_t, size_t, size_t,
@@ -407,6 +407,8 @@ noise_remote_begin_session (vlib_main_t * vm, noise_remote_t * r)
/* Now we need to add_new_keypair */
clib_rwlock_writer_lock (&r->r_keypair_lock);
+ /* Activate barrier to synchronization keys between threads */
+ vlib_worker_thread_barrier_sync (vm);
next = r->r_next;
current = r->r_current;
previous = r->r_previous;
@@ -438,6 +440,7 @@ noise_remote_begin_session (vlib_main_t * vm, noise_remote_t * r)
r->r_next = noise_remote_keypair_allocate (r);
*r->r_next = kp;
}
+ vlib_worker_thread_barrier_release (vm);
clib_rwlock_writer_unlock (&r->r_keypair_lock);
secure_zero_memory (&r->r_handshake, sizeof (r->r_handshake));
@@ -541,6 +544,41 @@ chacha20poly1305_calc (vlib_main_t * vm,
return (op->status == VNET_CRYPTO_OP_STATUS_COMPLETED);
}
+always_inline void
+wg_prepare_sync_op (vlib_main_t *vm, vnet_crypto_op_t **crypto_ops, u8 *src,
+ u32 src_len, u8 *dst, u8 *aad, u32 aad_len, u64 nonce,
+ vnet_crypto_op_id_t op_id,
+ vnet_crypto_key_index_t key_index, u32 bi, u8 *iv)
+{
+ vnet_crypto_op_t _op, *op = &_op;
+ u8 src_[] = {};
+
+ clib_memset (iv, 0, 4);
+ clib_memcpy (iv + 4, &nonce, sizeof (nonce));
+
+ vec_add2_aligned (crypto_ops[0], op, 1, CLIB_CACHE_LINE_BYTES);
+ vnet_crypto_op_init (op, op_id);
+
+ op->tag_len = NOISE_AUTHTAG_LEN;
+ if (op_id == VNET_CRYPTO_OP_CHACHA20_POLY1305_DEC)
+ {
+ op->tag = src + src_len;
+ op->flags |= VNET_CRYPTO_OP_FLAG_HMAC_CHECK;
+ }
+ else
+ op->tag = dst + src_len;
+
+ op->src = !src ? src_ : src;
+ op->len = src_len;
+
+ op->dst = dst;
+ op->key_index = key_index;
+ op->aad = aad;
+ op->aad_len = aad_len;
+ op->iv = iv;
+ op->user_data = bi;
+}
+
enum noise_state_crypt
noise_remote_encrypt (vlib_main_t * vm, noise_remote_t * r, uint32_t * r_idx,
uint64_t * nonce, uint8_t * src, size_t srclen,
@@ -592,26 +630,67 @@ error:
}
enum noise_state_crypt
-noise_remote_decrypt (vlib_main_t * vm, noise_remote_t * r, uint32_t r_idx,
- uint64_t nonce, uint8_t * src, size_t srclen,
- uint8_t * dst)
+noise_sync_remote_encrypt (vlib_main_t *vm, vnet_crypto_op_t **crypto_ops,
+ noise_remote_t *r, uint32_t *r_idx, uint64_t *nonce,
+ uint8_t *src, size_t srclen, uint8_t *dst, u32 bi,
+ u8 *iv, f64 time)
{
noise_keypair_t *kp;
enum noise_state_crypt ret = SC_FAILED;
- if (r->r_current != NULL && r->r_current->kp_local_index == r_idx)
- {
- kp = r->r_current;
- }
- else if (r->r_previous != NULL && r->r_previous->kp_local_index == r_idx)
- {
- kp = r->r_previous;
- }
- else if (r->r_next != NULL && r->r_next->kp_local_index == r_idx)
- {
- kp = r->r_next;
- }
- else
+ if ((kp = r->r_current) == NULL)
+ goto error;
+
+ /* We confirm that our values are within our tolerances. We want:
+ * - a valid keypair
+ * - our keypair to be less than REJECT_AFTER_TIME seconds old
+ * - our receive counter to be less than REJECT_AFTER_MESSAGES
+ * - our send counter to be less than REJECT_AFTER_MESSAGES
+ */
+ if (!kp->kp_valid ||
+ wg_birthdate_has_expired_opt (kp->kp_birthdate, REJECT_AFTER_TIME,
+ time) ||
+ kp->kp_ctr.c_recv >= REJECT_AFTER_MESSAGES ||
+ ((*nonce = noise_counter_send (&kp->kp_ctr)) > REJECT_AFTER_MESSAGES))
+ goto error;
+
+ /* We encrypt into the same buffer, so the caller must ensure that buf
+ * has NOISE_AUTHTAG_LEN bytes to store the MAC. The nonce and index
+ * are passed back out to the caller through the provided data pointer. */
+ *r_idx = kp->kp_remote_index;
+
+ wg_prepare_sync_op (vm, crypto_ops, src, srclen, dst, NULL, 0, *nonce,
+ VNET_CRYPTO_OP_CHACHA20_POLY1305_ENC, kp->kp_send_index,
+ bi, iv);
+
+ /* If our values are still within tolerances, but we are approaching
+ * the tolerances, we notify the caller with ESTALE that they should
+ * establish a new keypair. The current keypair can continue to be used
+ * until the tolerances are hit. We notify if:
+ * - our send counter is valid and not less than REKEY_AFTER_MESSAGES
+ * - we're the initiator and our keypair is older than
+ * REKEY_AFTER_TIME seconds */
+ ret = SC_KEEP_KEY_FRESH;
+ if ((kp->kp_valid && *nonce >= REKEY_AFTER_MESSAGES) ||
+ (kp->kp_is_initiator && wg_birthdate_has_expired_opt (
+ kp->kp_birthdate, REKEY_AFTER_TIME, time)))
+ goto error;
+
+ ret = SC_OK;
+error:
+ return ret;
+}
+
+enum noise_state_crypt
+noise_sync_remote_decrypt (vlib_main_t *vm, vnet_crypto_op_t **crypto_ops,
+ noise_remote_t *r, uint32_t r_idx, uint64_t nonce,
+ uint8_t *src, size_t srclen, uint8_t *dst, u32 bi,
+ u8 *iv, f64 time)
+{
+ noise_keypair_t *kp;
+ enum noise_state_crypt ret = SC_FAILED;
+
+ if ((kp = wg_get_active_keypair (r, r_idx)) == NULL)
{
goto error;
}
@@ -620,20 +699,17 @@ noise_remote_decrypt (vlib_main_t * vm, noise_remote_t * r, uint32_t r_idx,
* are the same as the encrypt routine.
*
* kp_ctr isn't locked here, we're happy to accept a racy read. */
- if (wg_birthdate_has_expired (kp->kp_birthdate, REJECT_AFTER_TIME) ||
+ if (wg_birthdate_has_expired_opt (kp->kp_birthdate, REJECT_AFTER_TIME,
+ time) ||
kp->kp_ctr.c_recv >= REJECT_AFTER_MESSAGES)
goto error;
/* Decrypt, then validate the counter. We don't want to validate the
* counter before decrypting as we do not know the message is authentic
* prior to decryption. */
- if (!chacha20poly1305_calc (vm, src, srclen, dst, NULL, 0, nonce,
- VNET_CRYPTO_OP_CHACHA20_POLY1305_DEC,
- kp->kp_recv_index))
- goto error;
-
- if (!noise_counter_recv (&kp->kp_ctr, nonce))
- goto error;
+ wg_prepare_sync_op (vm, crypto_ops, src, srclen, dst, NULL, 0, nonce,
+ VNET_CRYPTO_OP_CHACHA20_POLY1305_DEC, kp->kp_recv_index,
+ bi, iv);
/* If we've received the handshake confirming data packet then move the
* next keypair into current. If we do slide the next keypair in, then
@@ -662,10 +738,9 @@ noise_remote_decrypt (vlib_main_t * vm, noise_remote_t * r, uint32_t r_idx,
* REKEY_AFTER_TIME_RECV seconds. */
ret = SC_KEEP_KEY_FRESH;
kp = r->r_current;
- if (kp != NULL &&
- kp->kp_valid &&
- kp->kp_is_initiator &&
- wg_birthdate_has_expired (kp->kp_birthdate, REKEY_AFTER_TIME_RECV))
+ if (kp != NULL && kp->kp_valid && kp->kp_is_initiator &&
+ wg_birthdate_has_expired_opt (kp->kp_birthdate, REKEY_AFTER_TIME_RECV,
+ time))
goto error;
ret = SC_OK;
@@ -724,47 +799,6 @@ noise_counter_send (noise_counter_t * ctr)
return ret;
}
-static bool
-noise_counter_recv (noise_counter_t * ctr, uint64_t recv)
-{
- uint64_t i, top, index_recv, index_ctr;
- unsigned long bit;
- bool ret = false;
-
- /* Check that the recv counter is valid */
- if (ctr->c_recv >= REJECT_AFTER_MESSAGES || recv >= REJECT_AFTER_MESSAGES)
- goto error;
-
- /* If the packet is out of the window, invalid */
- if (recv + COUNTER_WINDOW_SIZE < ctr->c_recv)
- goto error;
-
- /* If the new counter is ahead of the current counter, we'll need to
- * zero out the bitmap that has previously been used */
- index_recv = recv / COUNTER_BITS;
- index_ctr = ctr->c_recv / COUNTER_BITS;
-
- if (recv > ctr->c_recv)
- {
- top = clib_min (index_recv - index_ctr, COUNTER_NUM);
- for (i = 1; i <= top; i++)
- ctr->c_backtrack[(i + index_ctr) & (COUNTER_NUM - 1)] = 0;
- ctr->c_recv = recv;
- }
-
- index_recv %= COUNTER_NUM;
- bit = 1ul << (recv % COUNTER_BITS);
-
- if (ctr->c_backtrack[index_recv] & bit)
- goto error;
-
- ctr->c_backtrack[index_recv] |= bit;
-
- ret = true;
-error:
- return ret;
-}
-
static void
noise_kdf (uint8_t * a, uint8_t * b, uint8_t * c, const uint8_t * x,
size_t a_len, size_t b_len, size_t c_len, size_t x_len,