* encryption mode: IVs must be unpredictable for AES-CBC whereas it can
* be predictable but should never be reused with the same key material
* for CTR and GCM.
- * We use a packet counter as the IV for CTR and GCM, and to ensure the
- * IV is unpredictable for CBC, it is then encrypted using the same key
- * as the message. You can refer to NIST SP800-38a and NIST SP800-38d
- * for more details. */
+ * To avoid reusing the same IVs between multiple VPP instances and between
+ * restarts, we use a properly chosen PRNG to generate IVs. To ensure the IV is
+ * unpredictable for CBC, it is then encrypted using the same key as the
+ * message. You can refer to NIST SP800-38a and NIST SP800-38d for more
+ * details. */
static_always_inline void *
esp_generate_iv (ipsec_sa_t *sa, void *payload, int iv_sz)
{
ASSERT (iv_sz >= sizeof (u64));
u64 *iv = (u64 *) (payload - iv_sz);
clib_memset_u8 (iv, 0, iv_sz);
- *iv = sa->iv_counter++;
+ *iv = clib_pcg64i_random_r (&sa->iv_prng);
return iv;
}
crypto_len += iv_sz;
}
- if (lb != b[0])
+ if (PREDICT_FALSE (lb != b[0]))
{
/* is chained */
op->flags |= VNET_CRYPTO_OP_FLAG_CHAINED_BUFFERS;
esp_post_data_t *post = esp_post_data (b);
u8 *tag, *iv, *aad = 0;
u8 flag = 0;
- u32 key_index;
+ const u32 key_index = sa->crypto_key_index;
i16 crypto_start_offset, integ_start_offset;
u16 crypto_total_len, integ_total_len;
crypto_total_len = integ_total_len = payload_len - icv_sz;
tag = payload + crypto_total_len;
- key_index = sa->linked_key_index;
-
/* generate the IV in front of the payload */
void *pkt_iv = esp_generate_iv (sa, payload, iv_sz);
/* constuct aad in a scratch space in front of the nonce */
aad = (u8 *) nonce - sizeof (esp_aead_t);
esp_aad_fill (aad, esp, sa, sa->seq_hi);
- key_index = sa->crypto_key_index;
}
else
{
is_async = im->async_mode | ipsec_sa_is_set_IS_ASYNC (sa0);
}
- if (PREDICT_FALSE (~0 == sa0->thread_index))
+ if (PREDICT_FALSE ((u16) ~0 == sa0->thread_index))
{
/* this is the first packet to use this SA, claim the SA
* for this thread. this could happen simultaneously on