diff options
Diffstat (limited to 'src/vnet/ipsec/esp_decrypt.c')
| -rw-r--r-- | src/vnet/ipsec/esp_decrypt.c | 155 |
1 files changed, 119 insertions, 36 deletions
diff --git a/src/vnet/ipsec/esp_decrypt.c b/src/vnet/ipsec/esp_decrypt.c index 36689480538..986087ba462 100644 --- a/src/vnet/ipsec/esp_decrypt.c +++ b/src/vnet/ipsec/esp_decrypt.c @@ -214,7 +214,7 @@ esp_remove_tail (vlib_main_t * vm, vlib_buffer_t * b, vlib_buffer_t * last, return pointer to it */ static_always_inline u8 * esp_move_icv (vlib_main_t * vm, vlib_buffer_t * first, - esp_decrypt_packet_data_t * pd, u16 icv_sz) + esp_decrypt_packet_data_t * pd, u16 icv_sz, u16 * dif) { vlib_buffer_t *before_last, *bp; u16 last_sz = pd->lb->current_length; @@ -232,6 +232,8 @@ esp_move_icv (vlib_main_t * vm, vlib_buffer_t * first, clib_memcpy_fast (lb_curr, vlib_buffer_get_tail (before_last) - first_sz, first_sz); before_last->current_length -= first_sz; + if (dif) + dif[0] = first_sz; pd->lb = before_last; pd->icv_removed = 1; pd->free_buffer_index = before_last->next_buffer; @@ -239,6 +241,76 @@ esp_move_icv (vlib_main_t * vm, vlib_buffer_t * first, return lb_curr; } +static_always_inline int +esp_insert_esn (vlib_main_t * vm, ipsec_sa_t * sa, + esp_decrypt_packet_data_t * pd, vnet_crypto_op_t * op, + u16 * len, vlib_buffer_t * b, u8 * payload) +{ + if (!ipsec_sa_is_set_USE_ESN (sa)) + return 1; + + /* shift ICV by 4 bytes to insert ESN */ + u32 seq_hi = clib_host_to_net_u32 (sa->seq_hi); + u8 tmp[ESP_MAX_ICV_SIZE], sz = sizeof (sa->seq_hi); + + if (pd->icv_removed) + { + u16 space_left = vlib_buffer_space_left_at_end (vm, pd->lb); + if (space_left >= sz) + { + clib_memcpy_fast (vlib_buffer_get_tail (pd->lb), &seq_hi, sz); + op->len += sz; + } + else + return 0; + + len[0] = b->current_length; + } + else + { + clib_memcpy_fast (tmp, payload + len[0], ESP_MAX_ICV_SIZE); + clib_memcpy_fast (payload + len[0], &seq_hi, sz); + clib_memcpy_fast (payload + len[0] + sz, tmp, ESP_MAX_ICV_SIZE); + op->len += sz; + op->digest += sz; + } + return 1; +} + +static_always_inline u8 * +esp_move_icv_esn (vlib_main_t * vm, vlib_buffer_t * first, + esp_decrypt_packet_data_t * pd, u16 icv_sz, ipsec_sa_t * sa, + u8 * extra_esn, vnet_crypto_op_t * op) +{ + u16 dif = 0; + u8 *digest = esp_move_icv (vm, first, pd, icv_sz, &dif); + if (dif) + op->len -= dif; + + if (ipsec_sa_is_set_USE_ESN (sa)) + { + u8 sz = sizeof (sa->seq_hi); + u32 seq_hi = clib_host_to_net_u32 (sa->seq_hi); + u16 space_left = vlib_buffer_space_left_at_end (vm, pd->lb); + + if (space_left >= sz) + { + clib_memcpy_fast (vlib_buffer_get_tail (pd->lb), &seq_hi, sz); + op->len += sz; + } + else + { + /* no space for ESN at the tail, use the next buffer + * (with ICV data) */ + ASSERT (pd->icv_removed); + vlib_buffer_t *tmp = vlib_get_buffer (vm, pd->free_buffer_index); + clib_memcpy_fast (vlib_buffer_get_current (tmp) - sz, &seq_hi, sz); + extra_esn[0] = 1; + } + } + return digest; +} + always_inline uword esp_decrypt_inline (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * from_frame, @@ -246,7 +318,6 @@ esp_decrypt_inline (vlib_main_t * vm, { ipsec_main_t *im = &ipsec_main; u32 thread_index = vm->thread_index; - u16 buffer_data_size = vlib_buffer_get_default_data_size (vm); u16 len; ipsec_per_thread_data_t *ptd = vec_elt_at_index (im->ptd, thread_index); u32 *from = vlib_frame_vector_args (from_frame); @@ -258,6 +329,7 @@ esp_decrypt_inline (vlib_main_t * vm, u32 current_sa_index = ~0, current_sa_bytes = 0, current_sa_pkts = 0; const u8 esp_sz = sizeof (esp_header_t); ipsec_sa_t *sa0 = 0; + vnet_crypto_op_t _op, *op = &_op; vnet_crypto_op_chunk_t *ch; vnet_crypto_op_t **crypto_ops = &ptd->crypto_ops; vnet_crypto_op_t **integ_ops = &ptd->integ_ops; @@ -327,7 +399,6 @@ esp_decrypt_inline (vlib_main_t * vm, /* store packet data for next round for easier prefetch */ pd->sa_data = cpd.sa_data; pd->current_data = b[0]->current_data; - pd->current_length = b[0]->current_length; pd->hdr_sz = pd->current_data - vnet_buffer (b[0])->l3_hdr_offset; payload = b[0]->data + pd->current_data; pd->seq = clib_host_to_net_u32 (((esp_header_t *) payload)->seq); @@ -346,17 +417,6 @@ esp_decrypt_inline (vlib_main_t * vm, } pd->current_length = b[0]->current_length; - /* we need 4 extra bytes for HMAC calculation when ESN are used */ - /* Chained buffers can process ESN as a separate chunk */ - if (pd->lb == b[0] && ipsec_sa_is_set_USE_ESN (sa0) && cpd.icv_sz && - (pd->lb->current_data + pd->lb->current_length + 4 - > buffer_data_size)) - { - b[0]->error = node->errors[ESP_DECRYPT_ERROR_NO_TAIL_SPACE]; - next[0] = ESP_DECRYPT_NEXT_DROP; - goto next; - } - /* anti-reply check */ if (ipsec_sa_anti_replay_check (sa0, pd->seq)) { @@ -378,9 +438,6 @@ esp_decrypt_inline (vlib_main_t * vm, if (PREDICT_TRUE (sa0->integ_op_id != VNET_CRYPTO_OP_NONE)) { - vnet_crypto_op_t *op; - vec_add2_aligned (integ_ops[0], op, 1, CLIB_CACHE_LINE_BYTES); - vnet_crypto_op_init (op, sa0->integ_op_id); op->key_index = sa0->integ_key_index; op->src = payload; @@ -394,14 +451,42 @@ esp_decrypt_inline (vlib_main_t * vm, { /* buffer is chained */ vlib_buffer_t *cb = b[0]; - op->flags |= VNET_CRYPTO_OP_FLAG_CHAINED_BUFFERS; - op->chunk_index = vec_len (ptd->chunks); + op->len = pd->current_length; + /* special case when ICV is splitted and needs to be reassembled + * first -> move it to the last buffer. Also take into account + * that ESN needs to be added after encrypted data and may or + * may not fit in the tail.*/ if (pd->lb->current_length < cpd.icv_sz) - op->digest = esp_move_icv (vm, b[0], pd, cpd.icv_sz); + { + u8 extra_esn = 0; + op->digest = + esp_move_icv_esn (vm, b[0], pd, cpd.icv_sz, sa0, + &extra_esn, op); + + if (extra_esn) + { + /* esn is in the last buffer, that was unlinked from + * the chain */ + op->len = b[0]->current_length; + } + else + { + if (pd->lb == b[0]) + { + /* we now have a single buffer of crypto data, adjust + * the length (second buffer contains only ICV) */ + integ_ops = &ptd->integ_ops; + crypto_ops = &ptd->crypto_ops; + goto out; + } + } + } else op->digest = vlib_buffer_get_tail (pd->lb) - cpd.icv_sz; + op->flags |= VNET_CRYPTO_OP_FLAG_CHAINED_BUFFERS; + op->chunk_index = vec_len (ptd->chunks); vec_add2 (ptd->chunks, ch, 1); ch->len = pd->current_length; ch->src = payload; @@ -472,6 +557,7 @@ esp_decrypt_inline (vlib_main_t * vm, ch->len += sz; } } + break; } else ch->len = cb->current_length; @@ -482,17 +568,10 @@ esp_decrypt_inline (vlib_main_t * vm, cb = vlib_get_buffer (vm, cb->next_buffer); } } - else if (ipsec_sa_is_set_USE_ESN (sa0)) - { - /* shift ICV by 4 bytes to insert ESN */ - u32 seq_hi = clib_host_to_net_u32 (sa0->seq_hi); - u8 tmp[ESP_MAX_ICV_SIZE], sz = sizeof (sa0->seq_hi); - clib_memcpy_fast (tmp, payload + len, ESP_MAX_ICV_SIZE); - clib_memcpy_fast (payload + len, &seq_hi, sz); - clib_memcpy_fast (payload + len + sz, tmp, ESP_MAX_ICV_SIZE); - op->len += sz; - op->digest += sz; - } + else + esp_insert_esn (vm, sa0, pd, op, &len, b[0], payload); + out: + vec_add_aligned (integ_ops[0], op, 1, CLIB_CACHE_LINE_BYTES); } payload += esp_sz; @@ -500,8 +579,6 @@ esp_decrypt_inline (vlib_main_t * vm, if (sa0->crypto_dec_op_id != VNET_CRYPTO_OP_NONE) { - vnet_crypto_op_t *op; - vec_add2_aligned (crypto_ops[0], op, 1, CLIB_CACHE_LINE_BYTES); vnet_crypto_op_init (op, sa0->crypto_dec_op_id); op->key_index = sa0->crypto_key_index; op->iv = payload; @@ -562,8 +639,9 @@ esp_decrypt_inline (vlib_main_t * vm, { if (pd->lb->current_length < cpd.icv_sz) { + u16 dif = 0; op->tag = - esp_move_icv (vm, b[0], pd, cpd.icv_sz); + esp_move_icv (vm, b[0], pd, cpd.icv_sz, &dif); /* this chunk does not contain crypto data */ op->n_chunks -= 1; @@ -571,7 +649,10 @@ esp_decrypt_inline (vlib_main_t * vm, /* and fix previous chunk's length as it might have been changed */ ASSERT (op->n_chunks > 0); - ch[-1].len = pd->lb->current_length; + if (pd->lb == b[0]) + ch[-1].len -= dif; + else + ch[-1].len = pd->lb->current_length; break; } else @@ -593,6 +674,8 @@ esp_decrypt_inline (vlib_main_t * vm, cb = vlib_get_buffer (vm, cb->next_buffer); } } + + vec_add_aligned (crypto_ops[0], op, 1, CLIB_CACHE_LINE_BYTES); } /* next */ @@ -743,7 +826,7 @@ esp_decrypt_inline (vlib_main_t * vm, clib_memcpy_le64 (ip, old_ip, ip_hdr_sz); b[0]->current_data = pd->current_data + adv - ip_hdr_sz; - b[0]->current_length = pd->current_length + ip_hdr_sz - adv; + b[0]->current_length += ip_hdr_sz - adv; esp_remove_tail (vm, b[0], pd->lb, tail); if (is_ip6) |