diff options
Diffstat (limited to 'src/plugins/ipsecmb/ah_decrypt.c')
| -rw-r--r-- | src/plugins/ipsecmb/ah_decrypt.c | 493 |
1 files changed, 493 insertions, 0 deletions
diff --git a/src/plugins/ipsecmb/ah_decrypt.c b/src/plugins/ipsecmb/ah_decrypt.c new file mode 100644 index 00000000000..e991671aa63 --- /dev/null +++ b/src/plugins/ipsecmb/ah_decrypt.c @@ -0,0 +1,493 @@ +/* + * ah_decrypt.c : ipsecmb AH 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 <vnet/ipsec/ah.h> + +#include <ipsecmb/ipsecmb.h> + +#define foreach_ah_decrypt_next \ + _ (DROP, "error-drop") \ + _ (IP4_INPUT, "ip4-input") \ + _ (IP6_INPUT, "ip6-input") \ + _ (IPSEC_GRE_INPUT, "ipsec-gre-input") + +#define _(v, s) AH_DECRYPT_NEXT_##v, +typedef enum +{ + foreach_ah_decrypt_next +#undef _ + AH_DECRYPT_N_NEXT, +} ah_decrypt_next_t; + +#define foreach_ah_decrypt_error \ + _ (RX_PKTS, "AH pkts received") \ + _ (DECRYPTION_FAILED, "AH decryption failed") \ + _ (INTEG_ERROR, "Integrity check failed") \ + _ (REPLAY, "SA replayed packet") \ + _ (NOT_IP, "Not IP packet (dropped)") + +typedef enum +{ +#define _(sym, str) AH_DECRYPT_ERROR_##sym, + foreach_ah_decrypt_error +#undef _ + AH_DECRYPT_N_ERROR, +} ah_decrypt_error_t; + +static char *ah_decrypt_error_strings[] = { +#define _(sym, string) string, + foreach_ah_decrypt_error +#undef _ +}; + +typedef struct +{ + ipsec_integ_alg_t integ_alg; +} ah_decrypt_trace_t; + +/* packet trace format function */ +static u8 * +format_ah_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 *); + ah_decrypt_trace_t *t = va_arg (*args, ah_decrypt_trace_t *); + + s = format (s, "ah: integrity %U", format_ipsec_integ_alg, t->integ_alg); + return s; +} + +typedef struct +{ + u8 tos; + u8 ttl; + u32 ip_version_traffic_class_and_flow_label; + u8 hop_limit; +} ip_mutable_data_t; + +#ifdef CLIB_MARCH_VARIANT +always_inline void +remove_ah (vlib_main_t * vm, vlib_node_runtime_t * node, u32 * bi0, + u32 * next0, ipsec_sa_t * sa0, u32 ip_hdr_size, u32 icv_size, + u8 icv_padding_len, ah_header_t * ah0, int is_ip6) +{ + vlib_buffer_t *b0 = vlib_get_buffer (vm, *bi0); + + if (sa0->is_tunnel) + { /* tunnel mode */ + vlib_buffer_advance (b0, ip_hdr_size + sizeof (ah_header_t) + icv_size + + icv_padding_len); + if (ah0->nexthdr == IP_PROTOCOL_IP_IN_IP) + *next0 = AH_DECRYPT_NEXT_IP4_INPUT; + else if (ah0->nexthdr == IP_PROTOCOL_IPV6) + *next0 = AH_DECRYPT_NEXT_IP6_INPUT; + else + { + clib_warning ("next header: 0x%x", ah0->nexthdr); + vlib_node_increment_counter (vm, node->node_index, + AH_DECRYPT_ERROR_DECRYPTION_FAILED, 1); + *next0 = AH_DECRYPT_NEXT_DROP; + return; + } + } + else + { /* transport mode */ + const size_t ip_hdr_offset = + sizeof (ah_header_t) + icv_size + icv_padding_len; + if (is_ip6) + { /* ipv6 */ + ip6_header_t *ih6 = + (ip6_header_t *) ((u8 *) vlib_buffer_get_current (b0) + + ip_hdr_offset); + u8 nexthdr = ah0->nexthdr; + memmove (ih6, vlib_buffer_get_current (b0), sizeof (ip6_header_t)); + vlib_buffer_advance (b0, ip_hdr_offset); + + *next0 = AH_DECRYPT_NEXT_IP6_INPUT; + ih6->protocol = nexthdr; + ih6->payload_length = + clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0) - + sizeof (ip6_header_t)); + } + else + { /* ipv4 */ + ip4_header_t *ih4 = + (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b0) + + ip_hdr_offset); + u8 nexthdr = ah0->nexthdr; + memmove (ih4, vlib_buffer_get_current (b0), sizeof (ip4_header_t)); + vlib_buffer_advance (b0, ip_hdr_offset); + + *next0 = AH_DECRYPT_NEXT_IP4_INPUT; + ih4->ip_version_and_header_length = 0x45; + ih4->fragment_id = 0; + ih4->flags_and_fragment_offset = 0; + ih4->protocol = nexthdr; + 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 (PREDICT_FALSE + ((vnet_buffer (b0)->ipsec.flags & IPSEC_FLAG_IPSEC_GRE_TUNNEL))) + { + *next0 = AH_DECRYPT_NEXT_IPSEC_GRE_INPUT; + } +} + +always_inline void +ah_finish_decrypt (vlib_main_t * vm, vlib_node_runtime_t * node, + JOB_AES_HMAC * job, u32 * bi0, u32 * next0, int is_ip6) +{ + ipsec_main_t *im = &ipsec_main; + *bi0 = (uintptr_t) job->user_data; + vlib_buffer_t *b0 = vlib_get_buffer (vm, *bi0); + ipsec_sa_t *sa0 = + pool_elt_at_index (im->sad, vnet_buffer (b0)->ipsec.sad_index); + ipsec_proto_main_t *em = &ipsec_proto_main; + u32 icv_size = em->ipsec_proto_main_integ_algs[sa0->integ_alg].trunc_size; + u32 ip_hdr_size = 0; + ip4_header_t *ih4 = vlib_buffer_get_current (b0); + size_t seq_size = 0; + if (PREDICT_TRUE (sa0->use_esn)) + { + seq_size = sizeof (u32); + } + ip_mutable_data_t *md = + (ip_mutable_data_t *) ((u8 *) vlib_buffer_get_current (b0) + + b0->current_length + seq_size + icv_size); + if (is_ip6) + { + ip_hdr_size = sizeof (ip6_header_t); + ip6_header_t *ih6 = vlib_buffer_get_current (b0); + ih6->ip_version_traffic_class_and_flow_label = + md->ip_version_traffic_class_and_flow_label; + ih6->hop_limit = md->hop_limit; + } + else + { + ip_hdr_size = ip4_header_bytes (ih4); + ih4->ttl = md->ttl; + ih4->tos = md->tos; + } + + u8 icv_padding_len = ah_calc_icv_padding_len (icv_size, is_ip6); + ah_header_t *ah0 = + (ah_header_t *) ((u8 *) vlib_buffer_get_current (b0) + ip_hdr_size); + void *digest = ah0 + 1; + void *sig = vlib_buffer_get_current (b0) + b0->current_length + seq_size; + + if (PREDICT_FALSE (memcmp (digest, sig, icv_size))) + { + vlib_node_increment_counter (vm, node->node_index, + AH_DECRYPT_ERROR_INTEG_ERROR, 1); + *next0 = AH_DECRYPT_NEXT_DROP; + return; + } + + if (PREDICT_TRUE (sa0->use_anti_replay)) + { + if (PREDICT_TRUE (sa0->use_esn)) + esp_replay_advance_esn (sa0, clib_host_to_net_u32 (ah0->seq_no)); + else + esp_replay_advance (sa0, clib_host_to_net_u32 (ah0->seq_no)); + } + remove_ah (vm, node, bi0, next0, sa0, ip_hdr_size, icv_size, + icv_padding_len, ah0, is_ip6); + vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0; +} + +always_inline uword +ah_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; + 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; + int icv_size = 0; + u32 thread_index = vlib_get_thread_index (); + MB_MGR *mgr = imbm->mb_mgr[thread_index]; + u32 packets_in_flight = 0; + + 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; + u32 next0; + vlib_buffer_t *b0; + ah_header_t *ah0; + ipsec_sa_t *sa0; + ipsecmb_sa_t *samb0; + u32 sa_index0 = ~0; + u32 seq; + ip4_header_t *ih4 = 0; + ip6_header_t *ih6 = 0; + u8 ip_hdr_size = 0; + + bi0 = from[0]; + from += 1; + n_left_from -= 1; + + next0 = AH_DECRYPT_NEXT_DROP; + + b0 = vlib_get_buffer (vm, bi0); + ih4 = vlib_buffer_get_current (b0); + ih6 = 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); + + if (is_ip6) + { + ip6_ext_header_t *prev = NULL; + ip6_ext_header_find_t (ih6, prev, ah0, IP_PROTOCOL_IPSEC_AH); + ip_hdr_size = sizeof (ip6_header_t); + ASSERT ((u8 *) ah0 - (u8 *) ih6 == ip_hdr_size); + } + else + { + ip_hdr_size = ip4_header_bytes (ih4); + ah0 = (ah_header_t *) (ih4 + 1); + } + + seq = clib_host_to_net_u32 (ah0->seq_no); + /* anti-replay check */ + // TODO UT remaining + if (sa0->use_anti_replay) + { + int rv = 0; + + if (PREDICT_TRUE (sa0->use_esn)) + rv = esp_replay_check_esn (sa0, seq); + else + rv = esp_replay_check (sa0, seq); + + if (PREDICT_FALSE (rv)) + { + clib_warning ("anti-replay SPI %u seq %u", sa0->spi, seq); + vlib_node_increment_counter (vm, node->node_index, + AH_DECRYPT_ERROR_REPLAY, 1); + goto trace; + } + } + + sa0->total_data_size += b0->current_length; + icv_size = + em->ipsec_proto_main_integ_algs[sa0->integ_alg].trunc_size; + if (PREDICT_TRUE (sa0->integ_alg != IPSEC_INTEG_ALG_NONE)) + { + u8 *icv = (u8 *) vlib_buffer_get_current (b0) + ip_hdr_size + + sizeof (ah_header_t); + size_t seq_size = 0; + if (PREDICT_TRUE (sa0->use_esn)) + { + *(u32 *) (vlib_buffer_get_current (b0) + + b0->current_length) = sa0->seq_hi; + seq_size = sizeof (u32); + } + clib_memcpy (vlib_buffer_get_current (b0) + b0->current_length + + seq_size, icv, icv_size); + memset (icv, 0, icv_size); + + ip_mutable_data_t *md = + (ip_mutable_data_t *) ((u8 *) vlib_buffer_get_current (b0) + + b0->current_length + seq_size + + icv_size); + if (is_ip6) + { + md->ip_version_traffic_class_and_flow_label = + ih6->ip_version_traffic_class_and_flow_label; + md->hop_limit = ih6->hop_limit; + ih6->ip_version_traffic_class_and_flow_label = 0x60; + ih6->hop_limit = 0; + } + else + { + md->tos = ih4->tos; + md->ttl = ih4->ttl; + ih4->tos = 0; + ih4->ttl = 0; + ih4->checksum = 0; + ih4->flags_and_fragment_offset = 0; + } + + JOB_AES_HMAC *job = IPSECMB_FUNC (get_next_job) (mgr); + job->src = vlib_buffer_get_current (b0); + job->hash_start_src_offset_in_bytes = 0; + job->cipher_mode = NULL_CIPHER; + job->hash_alg = imbm->integ_algs[sa0->integ_alg].hash_alg; + job->auth_tag_output_len_in_bytes = + imbm->integ_algs[sa0->integ_alg].hash_output_length; + job->auth_tag_output = icv; + job->msg_len_to_hash_in_bytes = b0->current_length + seq_size; + job->cipher_direction = DECRYPT; + job->chain_order = HASH_CIPHER; + job->u.HMAC._hashed_auth_key_xor_ipad = samb0->ipad_hash; + job->u.HMAC._hashed_auth_key_xor_opad = samb0->opad_hash; + + job->user_data = (void *) (uintptr_t) bi0; + job->user_data2 = (void *) (uintptr_t) next0; + vnet_buffer (b0)->ipsec.sad_index = sa_index0; + job = IPSECMB_FUNC (submit_job) (mgr); + ++packets_in_flight; + + if (!job) + { + continue; + } + --packets_in_flight; + ASSERT (STS_COMPLETED == job->status); + ah_finish_decrypt (vm, node, job, &bi0, &next0, is_ip6); + } + else + { + remove_ah (vm, node, &bi0, &next0, sa0, ip_hdr_size, icv_size, + 0, ah0, is_ip6); + } + trace: + to_next[0] = bi0; + to_next += 1; + n_left_to_next -= 1; + if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED)) + { + b0->flags |= VLIB_BUFFER_IS_TRACED; + ah_decrypt_trace_t *tr = + vlib_add_trace (vm, node, b0, sizeof (*tr)); + tr->integ_alg = sa0->integ_alg; + } + vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next, + n_left_to_next, bi0, next0); + } + + if (0 == n_left_from) + { + JOB_AES_HMAC *job = NULL; + while (n_left_to_next > 0 && (job = IPSECMB_FUNC (flush_job) (mgr))) + { + --packets_in_flight; + ASSERT (STS_COMPLETED == job->status); + u32 bi0, next0; + ah_finish_decrypt (vm, node, job, &bi0, &next0, is_ip6); + to_next[0] = bi0; + to_next += 1; + n_left_to_next -= 1; + vlib_buffer_t *b0 = vlib_get_buffer (vm, bi0); + if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED)) + { + ipsec_sa_t *sa0 = pool_elt_at_index (im->sad, + vnet_buffer + (b0)->ipsec.sad_index); + b0->flags |= VLIB_BUFFER_IS_TRACED; + ah_decrypt_trace_t *tr = + vlib_add_trace (vm, node, b0, sizeof (*tr)); + 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, AH_DECRYPT_ERROR_RX_PKTS, + from_frame->n_vectors); + + return from_frame->n_vectors; +} + +VLIB_NODE_FN (ah4_decrypt_ipsecmb_node) (vlib_main_t * vm, + vlib_node_runtime_t * node, + vlib_frame_t * from_frame) +{ + return ah_decrypt_ipsecmb_inline (vm, node, from_frame, 0 /*is_ip6 */ ); +} + +VLIB_NODE_FN (ah6_decrypt_ipsecmb_node) (vlib_main_t * vm, + vlib_node_runtime_t * node, + vlib_frame_t * from_frame) +{ + return ah_decrypt_ipsecmb_inline (vm, node, from_frame, 1 /*is_ip6 */ ); +} +#endif + +/* *INDENT-OFF* */ +VLIB_REGISTER_NODE (ah4_decrypt_ipsecmb_node) = { + .name = "ah4-decrypt-ipsecmb", + .vector_size = sizeof (u32), + .format_trace = format_ah_decrypt_trace, + .type = VLIB_NODE_TYPE_INTERNAL, + + .n_errors = ARRAY_LEN (ah_decrypt_error_strings), + .error_strings = ah_decrypt_error_strings, + + .n_next_nodes = AH_DECRYPT_N_NEXT, + .next_nodes = + { +#define _(s, n) [AH_DECRYPT_NEXT_##s] = n, + foreach_ah_decrypt_next +#undef _ + }, +}; +/* *INDENT-ON* */ + +/* *INDENT-OFF* */ +VLIB_REGISTER_NODE (ah6_decrypt_ipsecmb_node) = { + .name = "ah6-decrypt-ipsecmb", + .vector_size = sizeof (u32), + .format_trace = format_ah_decrypt_trace, + .type = VLIB_NODE_TYPE_INTERNAL, + + .n_errors = ARRAY_LEN (ah_decrypt_error_strings), + .error_strings = ah_decrypt_error_strings, + + .n_next_nodes = AH_DECRYPT_N_NEXT, + .next_nodes = + { +#define _(s, n) [AH_DECRYPT_NEXT_##s] = n, + foreach_ah_decrypt_next +#undef _ + }, +}; +/* *INDENT-ON* */ + +/* + * fd.io coding-style-patch-verification: ON + * + * Local Variables: + * eval: (c-set-style "gnu") + * End: + */ |