diff options
Diffstat (limited to 'src/vnet/ipsec/esp_encrypt.c')
| -rw-r--r-- | src/vnet/ipsec/esp_encrypt.c | 428 |
1 files changed, 428 insertions, 0 deletions
diff --git a/src/vnet/ipsec/esp_encrypt.c b/src/vnet/ipsec/esp_encrypt.c new file mode 100644 index 00000000..b2bc4e0b --- /dev/null +++ b/src/vnet/ipsec/esp_encrypt.c @@ -0,0 +1,428 @@ +/* + * esp_encrypt.c : IPSec ESP encrypt 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> + + +#define foreach_esp_encrypt_next \ +_(DROP, "error-drop") \ +_(IP4_LOOKUP, "ip4-lookup") \ +_(IP6_LOOKUP, "ip6-lookup") \ +_(INTERFACE_OUTPUT, "interface-output") + +#define _(v, s) ESP_ENCRYPT_NEXT_##v, +typedef enum +{ + foreach_esp_encrypt_next +#undef _ + ESP_ENCRYPT_N_NEXT, +} esp_encrypt_next_t; + +#define foreach_esp_encrypt_error \ + _(RX_PKTS, "ESP pkts received") \ + _(NO_BUFFER, "No buffer (packet dropped)") \ + _(DECRYPTION_FAILED, "ESP encryption failed") \ + _(SEQ_CYCLED, "sequence number cycled") + + +typedef enum +{ +#define _(sym,str) ESP_ENCRYPT_ERROR_##sym, + foreach_esp_encrypt_error +#undef _ + ESP_ENCRYPT_N_ERROR, +} esp_encrypt_error_t; + +static char *esp_encrypt_error_strings[] = { +#define _(sym,string) string, + foreach_esp_encrypt_error +#undef _ +}; + +vlib_node_registration_t esp_encrypt_node; + +typedef struct +{ + u32 spi; + u32 seq; + ipsec_crypto_alg_t crypto_alg; + ipsec_integ_alg_t integ_alg; +} esp_encrypt_trace_t; + +/* packet trace format function */ +static u8 * +format_esp_encrypt_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_encrypt_trace_t *t = va_arg (*args, esp_encrypt_trace_t *); + + s = format (s, "esp: spi %u seq %u crypto %U integrity %U", + t->spi, t->seq, + format_ipsec_crypto_alg, t->crypto_alg, + format_ipsec_integ_alg, t->integ_alg); + return s; +} + +always_inline void +esp_encrypt_aes_cbc (ipsec_crypto_alg_t alg, + u8 * in, u8 * out, size_t in_len, u8 * key, u8 * iv) +{ + esp_main_t *em = &esp_main; + u32 thread_index = vlib_get_thread_index (); + EVP_CIPHER_CTX *ctx = &(em->per_thread_data[thread_index].encrypt_ctx); + const EVP_CIPHER *cipher = NULL; + int out_len; + + ASSERT (alg < IPSEC_CRYPTO_N_ALG); + + if (PREDICT_FALSE (em->esp_crypto_algs[alg].type == IPSEC_CRYPTO_ALG_NONE)) + return; + + if (PREDICT_FALSE + (alg != em->per_thread_data[thread_index].last_encrypt_alg)) + { + cipher = em->esp_crypto_algs[alg].type; + em->per_thread_data[thread_index].last_encrypt_alg = alg; + } + + EVP_EncryptInit_ex (ctx, cipher, NULL, key, iv); + + EVP_EncryptUpdate (ctx, out, &out_len, in, in_len); + EVP_EncryptFinal_ex (ctx, out + out_len, &out_len); +} + +static uword +esp_encrypt_node_fn (vlib_main_t * vm, + vlib_node_runtime_t * node, vlib_frame_t * from_frame) +{ + u32 n_left_from, *from, *to_next = 0, next_index; + from = vlib_frame_vector_args (from_frame); + n_left_from = from_frame->n_vectors; + ipsec_main_t *im = &ipsec_main; + u32 *recycle = 0; + u32 thread_index = vlib_get_thread_index (); + + ipsec_alloc_empty_buffers (vm, im); + + u32 *empty_buffers = im->empty_buffers[thread_index]; + + if (PREDICT_FALSE (vec_len (empty_buffers) < n_left_from)) + { + vlib_node_increment_counter (vm, esp_encrypt_node.index, + ESP_ENCRYPT_ERROR_NO_BUFFER, n_left_from); + clib_warning ("no enough empty buffers. discarding frame"); + goto free_buffers_and_exit; + } + + next_index = node->cached_next_index; + + while (n_left_from > 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 i_bi0, o_bi0, next0; + vlib_buffer_t *i_b0, *o_b0 = 0; + u32 sa_index0; + ipsec_sa_t *sa0; + ip4_and_esp_header_t *ih0, *oh0 = 0; + ip6_and_esp_header_t *ih6_0, *oh6_0 = 0; + uword last_empty_buffer; + esp_header_t *o_esp0; + esp_footer_t *f0; + u8 is_ipv6; + u8 ip_hdr_size; + u8 next_hdr_type; + u32 ip_proto = 0; + u8 transport_mode = 0; + + i_bi0 = from[0]; + from += 1; + n_left_from -= 1; + n_left_to_next -= 1; + + next0 = ESP_ENCRYPT_NEXT_DROP; + + i_b0 = vlib_get_buffer (vm, i_bi0); + sa_index0 = vnet_buffer (i_b0)->ipsec.sad_index; + sa0 = pool_elt_at_index (im->sad, sa_index0); + + if (PREDICT_FALSE (esp_seq_advance (sa0))) + { + clib_warning ("sequence number counter has cycled SPI %u", + sa0->spi); + vlib_node_increment_counter (vm, esp_encrypt_node.index, + ESP_ENCRYPT_ERROR_SEQ_CYCLED, 1); + //TODO: rekey SA + o_bi0 = i_bi0; + to_next[0] = o_bi0; + to_next += 1; + goto trace; + } + + sa0->total_data_size += i_b0->current_length; + + /* grab free buffer */ + last_empty_buffer = vec_len (empty_buffers) - 1; + o_bi0 = empty_buffers[last_empty_buffer]; + o_b0 = vlib_get_buffer (vm, o_bi0); + o_b0->flags = VLIB_BUFFER_TOTAL_LENGTH_VALID; + o_b0->current_data = sizeof (ethernet_header_t); + ih0 = vlib_buffer_get_current (i_b0); + vlib_prefetch_buffer_with_index (vm, + empty_buffers[last_empty_buffer - + 1], STORE); + _vec_len (empty_buffers) = last_empty_buffer; + to_next[0] = o_bi0; + to_next += 1; + + /* add old buffer to the recycle list */ + vec_add1 (recycle, i_bi0); + + /* is ipv6 */ + if (PREDICT_FALSE + ((ih0->ip4.ip_version_and_header_length & 0xF0) == 0x60)) + { + is_ipv6 = 1; + ih6_0 = vlib_buffer_get_current (i_b0); + ip_hdr_size = sizeof (ip6_header_t); + next_hdr_type = IP_PROTOCOL_IPV6; + oh6_0 = vlib_buffer_get_current (o_b0); + o_esp0 = vlib_buffer_get_current (o_b0) + sizeof (ip6_header_t); + + oh6_0->ip6.ip_version_traffic_class_and_flow_label = + ih6_0->ip6.ip_version_traffic_class_and_flow_label; + oh6_0->ip6.protocol = IP_PROTOCOL_IPSEC_ESP; + oh6_0->ip6.hop_limit = 254; + oh6_0->ip6.src_address.as_u64[0] = + ih6_0->ip6.src_address.as_u64[0]; + oh6_0->ip6.src_address.as_u64[1] = + ih6_0->ip6.src_address.as_u64[1]; + oh6_0->ip6.dst_address.as_u64[0] = + ih6_0->ip6.dst_address.as_u64[0]; + oh6_0->ip6.dst_address.as_u64[1] = + ih6_0->ip6.dst_address.as_u64[1]; + oh6_0->esp.spi = clib_net_to_host_u32 (sa0->spi); + oh6_0->esp.seq = clib_net_to_host_u32 (sa0->seq); + ip_proto = ih6_0->ip6.protocol; + + next0 = ESP_ENCRYPT_NEXT_IP6_LOOKUP; + } + else + { + is_ipv6 = 0; + ip_hdr_size = sizeof (ip4_header_t); + next_hdr_type = IP_PROTOCOL_IP_IN_IP; + oh0 = vlib_buffer_get_current (o_b0); + o_esp0 = vlib_buffer_get_current (o_b0) + sizeof (ip4_header_t); + + oh0->ip4.ip_version_and_header_length = 0x45; + oh0->ip4.tos = ih0->ip4.tos; + oh0->ip4.fragment_id = 0; + oh0->ip4.flags_and_fragment_offset = 0; + oh0->ip4.ttl = 254; + oh0->ip4.protocol = IP_PROTOCOL_IPSEC_ESP; + oh0->ip4.src_address.as_u32 = ih0->ip4.src_address.as_u32; + oh0->ip4.dst_address.as_u32 = ih0->ip4.dst_address.as_u32; + oh0->esp.spi = clib_net_to_host_u32 (sa0->spi); + oh0->esp.seq = clib_net_to_host_u32 (sa0->seq); + ip_proto = ih0->ip4.protocol; + + next0 = ESP_ENCRYPT_NEXT_IP4_LOOKUP; + } + + if (PREDICT_TRUE + (!is_ipv6 && sa0->is_tunnel && !sa0->is_tunnel_ip6)) + { + oh0->ip4.src_address.as_u32 = sa0->tunnel_src_addr.ip4.as_u32; + oh0->ip4.dst_address.as_u32 = sa0->tunnel_dst_addr.ip4.as_u32; + + vnet_buffer (o_b0)->sw_if_index[VLIB_TX] = (u32) ~ 0; + } + else if (is_ipv6 && sa0->is_tunnel && sa0->is_tunnel_ip6) + { + oh6_0->ip6.src_address.as_u64[0] = + sa0->tunnel_src_addr.ip6.as_u64[0]; + oh6_0->ip6.src_address.as_u64[1] = + sa0->tunnel_src_addr.ip6.as_u64[1]; + oh6_0->ip6.dst_address.as_u64[0] = + sa0->tunnel_dst_addr.ip6.as_u64[0]; + oh6_0->ip6.dst_address.as_u64[1] = + sa0->tunnel_dst_addr.ip6.as_u64[1]; + + vnet_buffer (o_b0)->sw_if_index[VLIB_TX] = (u32) ~ 0; + } + else + { + next_hdr_type = ip_proto; + if (vnet_buffer (i_b0)->sw_if_index[VLIB_TX] != ~0) + { + transport_mode = 1; + ethernet_header_t *ieh0, *oeh0; + ieh0 = + (ethernet_header_t *) ((u8 *) + vlib_buffer_get_current (i_b0) - + sizeof (ethernet_header_t)); + oeh0 = (ethernet_header_t *) o_b0->data; + clib_memcpy (oeh0, ieh0, sizeof (ethernet_header_t)); + next0 = ESP_ENCRYPT_NEXT_INTERFACE_OUTPUT; + vnet_buffer (o_b0)->sw_if_index[VLIB_TX] = + vnet_buffer (i_b0)->sw_if_index[VLIB_TX]; + } + vlib_buffer_advance (i_b0, ip_hdr_size); + } + + ASSERT (sa0->crypto_alg < IPSEC_CRYPTO_N_ALG); + + if (PREDICT_TRUE (sa0->crypto_alg != IPSEC_CRYPTO_ALG_NONE)) + { + + const int BLOCK_SIZE = 16; + const int IV_SIZE = 16; + int blocks = 1 + (i_b0->current_length + 1) / BLOCK_SIZE; + + /* pad packet in input buffer */ + u8 pad_bytes = BLOCK_SIZE * blocks - 2 - i_b0->current_length; + u8 i; + u8 *padding = + vlib_buffer_get_current (i_b0) + i_b0->current_length; + i_b0->current_length = BLOCK_SIZE * blocks; + for (i = 0; i < pad_bytes; ++i) + { + padding[i] = i + 1; + } + f0 = vlib_buffer_get_current (i_b0) + i_b0->current_length - 2; + f0->pad_length = pad_bytes; + f0->next_header = next_hdr_type; + + o_b0->current_length = ip_hdr_size + sizeof (esp_header_t) + + BLOCK_SIZE * blocks + IV_SIZE; + + vnet_buffer (o_b0)->sw_if_index[VLIB_RX] = + vnet_buffer (i_b0)->sw_if_index[VLIB_RX]; + + u8 iv[16]; + RAND_bytes (iv, sizeof (iv)); + + clib_memcpy ((u8 *) vlib_buffer_get_current (o_b0) + + ip_hdr_size + sizeof (esp_header_t), iv, 16); + + esp_encrypt_aes_cbc (sa0->crypto_alg, + (u8 *) vlib_buffer_get_current (i_b0), + (u8 *) vlib_buffer_get_current (o_b0) + + ip_hdr_size + sizeof (esp_header_t) + + IV_SIZE, BLOCK_SIZE * blocks, + sa0->crypto_key, iv); + } + + o_b0->current_length += hmac_calc (sa0->integ_alg, sa0->integ_key, + sa0->integ_key_len, + (u8 *) o_esp0, + o_b0->current_length - + ip_hdr_size, + vlib_buffer_get_current (o_b0) + + o_b0->current_length, + sa0->use_esn, sa0->seq_hi); + + + if (PREDICT_FALSE (is_ipv6)) + { + oh6_0->ip6.payload_length = + clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, o_b0) - + sizeof (ip6_header_t)); + } + else + { + oh0->ip4.length = + clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, o_b0)); + oh0->ip4.checksum = ip4_header_checksum (&oh0->ip4); + } + + if (transport_mode) + vlib_buffer_reset (o_b0); + + trace: + if (PREDICT_FALSE (i_b0->flags & VLIB_BUFFER_IS_TRACED)) + { + if (o_b0) + { + o_b0->flags |= VLIB_BUFFER_IS_TRACED; + o_b0->trace_index = i_b0->trace_index; + esp_encrypt_trace_t *tr = + vlib_add_trace (vm, node, o_b0, sizeof (*tr)); + tr->spi = sa0->spi; + tr->seq = sa0->seq - 1; + 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, o_bi0, + next0); + } + vlib_put_next_frame (vm, node, next_index, n_left_to_next); + } + vlib_node_increment_counter (vm, esp_encrypt_node.index, + ESP_ENCRYPT_ERROR_RX_PKTS, + from_frame->n_vectors); + +free_buffers_and_exit: + if (recycle) + vlib_buffer_free (vm, recycle, vec_len (recycle)); + vec_free (recycle); + return from_frame->n_vectors; +} + + +/* *INDENT-OFF* */ +VLIB_REGISTER_NODE (esp_encrypt_node) = { + .function = esp_encrypt_node_fn, + .name = "esp-encrypt", + .vector_size = sizeof (u32), + .format_trace = format_esp_encrypt_trace, + .type = VLIB_NODE_TYPE_INTERNAL, + + .n_errors = ARRAY_LEN(esp_encrypt_error_strings), + .error_strings = esp_encrypt_error_strings, + + .n_next_nodes = ESP_ENCRYPT_N_NEXT, + .next_nodes = { +#define _(s,n) [ESP_ENCRYPT_NEXT_##s] = n, + foreach_esp_encrypt_next +#undef _ + }, +}; +/* *INDENT-ON* */ + +VLIB_NODE_FUNCTION_MULTIARCH (esp_encrypt_node, esp_encrypt_node_fn) +/* + * fd.io coding-style-patch-verification: ON + * + * Local Variables: + * eval: (c-set-style "gnu") + * End: + */ |