diff options
Diffstat (limited to 'src/plugins/ipsecmb/esp_decrypt.c')
| -rw-r--r-- | src/plugins/ipsecmb/esp_decrypt.c | 471 |
1 files changed, 471 insertions, 0 deletions
diff --git a/src/plugins/ipsecmb/esp_decrypt.c b/src/plugins/ipsecmb/esp_decrypt.c new file mode 100644 index 00000000000..835f41eb35d --- /dev/null +++ b/src/plugins/ipsecmb/esp_decrypt.c @@ -0,0 +1,471 @@ +/* + * esp_decrypt.c : ipsecmb ESP decrypt node + * + * Copyright (c) 2015 Cisco and/or its affiliates. + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at: + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#include <vnet/vnet.h> +#include <vnet/api_errno.h> +#include <vnet/ip/ip.h> + +#include <vnet/ipsec/ipsec.h> +#include <vnet/ipsec/esp.h> +#include <ipsecmb/ipsecmb.h> + +#define foreach_esp_decrypt_next \ +_(DROP, "error-drop") \ +_(IP4_INPUT, "ip4-input") \ +_(IP6_INPUT, "ip6-input") \ +_(IPSEC_GRE_INPUT, "ipsec-gre-input") + +#define _(v, s) ESP_DECRYPT_NEXT_##v, +typedef enum +{ + foreach_esp_decrypt_next +#undef _ + ESP_DECRYPT_N_NEXT, +} esp_decrypt_next_t; + + +#define foreach_esp_decrypt_error \ + _(RX_PKTS, "ESP pkts received") \ + _(NO_BUFFER, "No buffer (packed dropped)") \ + _(DECRYPTION_FAILED, "ESP decryption failed") \ + _(INTEG_ERROR, "Integrity check failed") \ + _(REPLAY, "SA replayed packet") \ + _(NOT_IP, "Not IP packet (dropped)") + +typedef enum +{ +#define _(sym,str) ESP_DECRYPT_ERROR_##sym, + foreach_esp_decrypt_error +#undef _ + ESP_DECRYPT_N_ERROR, +} esp_decrypt_error_t; + +static char *esp_decrypt_error_strings[] = { +#define _(sym,string) string, + foreach_esp_decrypt_error +#undef _ +}; + +typedef struct +{ + ipsec_crypto_alg_t crypto_alg; + ipsec_integ_alg_t integ_alg; +} esp_decrypt_trace_t; + +/* packet trace format function */ +static u8 * +format_esp_decrypt_trace (u8 * s, va_list * args) +{ + CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *); + CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *); + esp_decrypt_trace_t *t = va_arg (*args, esp_decrypt_trace_t *); + + s = format (s, "esp: crypto %U integrity %U", + format_ipsec_crypto_alg, t->crypto_alg, + format_ipsec_integ_alg, t->integ_alg); + return s; +} + +#ifdef CLIB_MARCH_VARIANT +always_inline void +esp_finish_decrypt (vlib_main_t * vm, vlib_node_runtime_t * node, + JOB_AES_HMAC * job, u32 * next0, ipsec_sa_t * sa0, + int is_ip6) +{ + u32 bi0 = (uintptr_t) job->user_data; + vlib_buffer_t *b0 = vlib_get_buffer (vm, bi0); + esp_footer_t *f0; + ip4_header_t *ih4 = vlib_buffer_get_current (b0); + ip6_header_t *ih6 = vlib_buffer_get_current (b0); + + if (NULL_HASH != job->hash_alg) + { + if (0 != + memcmp (job->auth_tag_output, + job->auth_tag_output - job->auth_tag_output_len_in_bytes, + job->auth_tag_output_len_in_bytes)) + { + vlib_node_increment_counter (vm, node->node_index, + ESP_DECRYPT_ERROR_INTEG_ERROR, 1); + *next0 = ESP_DECRYPT_NEXT_DROP; + return; + } + } + + f0 = (esp_footer_t *) ((u8 *) vlib_buffer_get_current (b0) + + b0->current_length); + b0->current_length -= f0->pad_length; + + /* tunnel mode */ + if (sa0->is_tunnel) + { + if (f0->next_header == IP_PROTOCOL_IP_IN_IP) + { + *next0 = ESP_DECRYPT_NEXT_IP4_INPUT; + } + else if (f0->next_header == IP_PROTOCOL_IPV6) + { + *next0 = ESP_DECRYPT_NEXT_IP6_INPUT; + } + else + { + vlib_node_increment_counter (vm, node->node_index, + ESP_DECRYPT_ERROR_DECRYPTION_FAILED, + 1); + *next0 = ESP_DECRYPT_NEXT_DROP; + return; + } + } + /* transport mode */ + else + { + if (is_ip6) + { + *next0 = ESP_DECRYPT_NEXT_IP6_INPUT; + ih6->protocol = f0->next_header; + ih6->payload_length = + clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0) - + sizeof (ip6_header_t)); + } + else + { + *next0 = ESP_DECRYPT_NEXT_IP4_INPUT; + ih4->fragment_id = 0; + ih4->flags_and_fragment_offset = 0; + ih4->protocol = f0->next_header; + ih4->length = + clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0)); + ih4->checksum = ip4_header_checksum (ih4); + } + } + + /* for IPSec-GRE tunnel next node is ipsec-gre-input */ + if ((vnet_buffer (b0)->ipsec.flags & IPSEC_FLAG_IPSEC_GRE_TUNNEL)) + { + *next0 = ESP_DECRYPT_NEXT_IPSEC_GRE_INPUT; + } + + vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0; + if (sa0->use_anti_replay) + { + if (sa0->use_esn) + esp_replay_advance_esn (sa0, vnet_buffer (b0)->ipsec.seq); + else + esp_replay_advance (sa0, vnet_buffer (b0)->ipsec.seq); + } +} + +always_inline uword +esp_decrypt_ipsecmb_inline (vlib_main_t * vm, vlib_node_runtime_t * node, + vlib_frame_t * from_frame, int is_ip6) +{ + u32 n_left_from, *from, next_index, *to_next; + u32 packets_in_flight = 0; + ipsec_main_t *im = &ipsec_main; + ipsecmb_main_t *imbm = &ipsecmb_main; + ipsec_proto_main_t *em = &ipsec_proto_main; + from = vlib_frame_vector_args (from_frame); + n_left_from = from_frame->n_vectors; + u32 thread_index = vlib_get_thread_index (); + MB_MGR *mgr = imbm->mb_mgr[thread_index]; + u32 *to_be_freed = NULL; + + next_index = node->cached_next_index; + + while (n_left_from > 0 || packets_in_flight > 0) + { + u32 n_left_to_next; + + vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next); + + while (n_left_from > 0 && n_left_to_next > 0) + { + u32 bi0, next0; + vlib_buffer_t *b0; + esp_header_t *esp0; + ipsec_sa_t *sa0; + ipsecmb_sa_t *samb0; + u32 sa_index0 = ~0; + u32 seq; + + bi0 = from[0]; + from += 1; + n_left_from -= 1; + + next0 = ESP_DECRYPT_NEXT_DROP; + + b0 = vlib_get_buffer (vm, bi0); + esp0 = vlib_buffer_get_current (b0); + + sa_index0 = vnet_buffer (b0)->ipsec.sad_index; + sa0 = pool_elt_at_index (im->sad, sa_index0); + samb0 = pool_elt_at_index (imbm->sad, sa_index0); + + vnet_buffer (b0)->ipsec.seq = seq = + clib_host_to_net_u32 (esp0->seq); + + /* anti-replay check */ + if (sa0->use_anti_replay) + { + int rv = 0; + + if (sa0->use_esn) + rv = esp_replay_check_esn (sa0, seq); + else + rv = esp_replay_check (sa0, seq); + + if (PREDICT_FALSE (rv)) + { + vlib_node_increment_counter (vm, node->node_index, + ESP_DECRYPT_ERROR_REPLAY, 1); + goto trace; + } + } + + sa0->total_data_size += b0->current_length; + + if (PREDICT_FALSE (b0->n_add_refs > 0)) + { + vec_add1 (to_be_freed, bi0); + b0 = vlib_buffer_copy (vm, b0); + bi0 = vlib_get_buffer_index (vm, b0); + } + + JOB_AES_HMAC *job = IPSECMB_FUNC (get_next_job) (mgr); + int trunc_size = 0; + if (sa0->integ_alg != IPSEC_INTEG_ALG_NONE) + { + trunc_size = + em->ipsec_proto_main_integ_algs[sa0->integ_alg].trunc_size; + // put calculated auth tag after in-packet auth tag + job->auth_tag_output = + vlib_buffer_get_current (b0) + b0->current_length; + b0->current_length -= trunc_size; + job->msg_len_to_hash_in_bytes = b0->current_length; + job->auth_tag_output_len_in_bytes = trunc_size; + job->u.HMAC._hashed_auth_key_xor_ipad = samb0->ipad_hash; + job->u.HMAC._hashed_auth_key_xor_opad = samb0->opad_hash; + } + + job->hash_alg = imbm->integ_algs[sa0->integ_alg].hash_alg; + u8 ip_hdr_size = 0; + + if ((sa0->crypto_alg >= IPSEC_CRYPTO_ALG_AES_CBC_128 && + sa0->crypto_alg <= IPSEC_CRYPTO_ALG_AES_CBC_256) || + (sa0->crypto_alg >= IPSEC_CRYPTO_ALG_DES_CBC && + sa0->crypto_alg <= IPSEC_CRYPTO_ALG_3DES_CBC)) + { + const int block_size = + em->ipsec_proto_main_crypto_algs[sa0->crypto_alg].block_size; + const int iv_size = + em->ipsec_proto_main_crypto_algs[sa0->crypto_alg].iv_size; + + int blocks = + (b0->current_length - sizeof (esp_header_t) - + iv_size) / block_size; + if (b0->current_length - sizeof (esp_header_t) - iv_size < + block_size || blocks <= 0) + { + vlib_node_increment_counter (vm, node->node_index, + ESP_DECRYPT_ERROR_INTEG_ERROR, + 1); + goto trace; + } + + /* transport mode */ + if (!sa0->is_tunnel) + { + if (b0->flags & VNET_BUFFER_F_L3_HDR_OFFSET_VALID) + { + if (is_ip6) + { + ip_hdr_size = sizeof (ip6_header_t); + } + else + { + ip_hdr_size = sizeof (ip4_header_t); + } + } + else + { + vlib_node_increment_counter (vm, node->node_index, + ESP_DECRYPT_ERROR_NOT_IP, + 1); + goto trace; + } + } + + job->chain_order = HASH_CIPHER; + job->cipher_direction = DECRYPT; + job->src = (u8 *) esp0; + job->dst = (u8 *) esp0; + vlib_buffer_advance (b0, -ip_hdr_size); + job->cipher_mode = + imbm->crypto_algs[sa0->crypto_alg].cipher_mode; + job->aes_enc_key_expanded = samb0->aes_enc_key_expanded; + job->aes_dec_key_expanded = samb0->aes_dec_key_expanded; + job->aes_key_len_in_bytes = sa0->crypto_key_len; + job->iv = esp0->data; + job->iv_len_in_bytes = iv_size; + job->msg_len_to_cipher_in_bytes = blocks * block_size; + job->cipher_start_src_offset_in_bytes = + sizeof (esp_header_t) + iv_size; + job->hash_start_src_offset_in_bytes = 0; + + job->user_data = (void *) (uintptr_t) bi0; + job->user_data2 = sa0; + b0->current_length = + (blocks * block_size) - sizeof (esp_footer_t) + ip_hdr_size; + ASSERT ((u8 *) vlib_buffer_get_current (b0) + + b0->current_length < job->auth_tag_output); + b0->flags |= VLIB_BUFFER_TOTAL_LENGTH_VALID; + + job = IPSECMB_FUNC (submit_job) (mgr); + ++packets_in_flight; + + if (!job) + { + continue; + } + + --packets_in_flight; + + sa0 = job->user_data2; + bi0 = (uintptr_t) job->user_data; + b0 = vlib_get_buffer (vm, bi0); + esp_finish_decrypt (vm, node, job, &next0, sa0, is_ip6); + + trace: + to_next[0] = bi0; + to_next += 1; + n_left_to_next -= 1; + + if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED)) + { + esp_decrypt_trace_t *tr = + vlib_add_trace (vm, node, b0, sizeof (*tr)); + tr->crypto_alg = sa0->crypto_alg; + tr->integ_alg = sa0->integ_alg; + } + + vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next, + n_left_to_next, bi0, next0); + } + } + + if (PREDICT_FALSE (n_left_from == 0 && packets_in_flight > 0)) + { + JOB_AES_HMAC *job = NULL; + while (n_left_to_next > 0 && (job = IPSECMB_FUNC (flush_job) (mgr))) + { + --packets_in_flight; + u32 bi0, next0; + bi0 = (uintptr_t) job->user_data; + vlib_buffer_t *i_b0 = vlib_get_buffer (vm, bi0); + + ipsec_sa_t *sa0 = job->user_data2; + esp_finish_decrypt (vm, node, job, &next0, sa0, is_ip6); + + to_next[0] = bi0; + to_next += 1; + n_left_to_next -= 1; + + if (PREDICT_FALSE (i_b0->flags & VLIB_BUFFER_IS_TRACED)) + { + esp_decrypt_trace_t *tr = + vlib_add_trace (vm, node, i_b0, sizeof (*tr)); + tr->crypto_alg = sa0->crypto_alg; + tr->integ_alg = sa0->integ_alg; + } + + vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next, + n_left_to_next, bi0, next0); + } + } + + vlib_put_next_frame (vm, node, next_index, n_left_to_next); + } + vlib_node_increment_counter (vm, node->node_index, + ESP_DECRYPT_ERROR_RX_PKTS, + from_frame->n_vectors); + + if (to_be_freed) + vlib_buffer_free (vm, to_be_freed, vec_len (to_be_freed)); + vec_free (to_be_freed); + return from_frame->n_vectors; +} + +VLIB_NODE_FN (esp4_decrypt_ipsecmb_node) (vlib_main_t * vm, + vlib_node_runtime_t * node, + vlib_frame_t * from_frame) +{ + return esp_decrypt_ipsecmb_inline (vm, node, from_frame, 0 /*is_ip6 */ ); +} + +VLIB_NODE_FN (esp6_decrypt_ipsecmb_node) (vlib_main_t * vm, + vlib_node_runtime_t * node, + vlib_frame_t * from_frame) +{ + return esp_decrypt_ipsecmb_inline (vm, node, from_frame, 1 /*is_ip6 */ ); +} +#endif + +/* *INDENT-OFF* */ +VLIB_REGISTER_NODE (esp4_decrypt_ipsecmb_node) = { + .name = "esp4-decrypt-ipsecmb", + .vector_size = sizeof (u32), + .format_trace = format_esp_decrypt_trace, + .type = VLIB_NODE_TYPE_INTERNAL, + + .n_errors = ARRAY_LEN(esp_decrypt_error_strings), + .error_strings = esp_decrypt_error_strings, + + .n_next_nodes = ESP_DECRYPT_N_NEXT, + .next_nodes = { +#define _(s,n) [ESP_DECRYPT_NEXT_##s] = n, + foreach_esp_decrypt_next +#undef _ + }, +}; +/* *INDENT-ON* */ + +/* *INDENT-OFF* */ +VLIB_REGISTER_NODE (esp6_decrypt_ipsecmb_node) = { + .name = "esp6-decrypt-ipsecmb", + .vector_size = sizeof (u32), + .format_trace = format_esp_decrypt_trace, + .type = VLIB_NODE_TYPE_INTERNAL, + + .n_errors = ARRAY_LEN(esp_decrypt_error_strings), + .error_strings = esp_decrypt_error_strings, + + .n_next_nodes = ESP_DECRYPT_N_NEXT, + .next_nodes = { +#define _(s,n) [ESP_DECRYPT_NEXT_##s] = n, + foreach_esp_decrypt_next +#undef _ + }, +}; +/* *INDENT-ON* */ + +/* + * fd.io coding-style-patch-verification: ON + * + * Local Variables: + * eval: (c-set-style "gnu") + * End: + */ |