/* * 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> ipsec_proto_main_t ipsec_proto_main; #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_cbc (ipsec_crypto_alg_t alg, u8 * in, u8 * out, size_t in_len, u8 * key, u8 * iv) { ipsec_proto_main_t *em = &ipsec_proto_main; u32 thread_index = vlib_get_thread_index (); #if OPENSSL_VERSION_NUMBER >= 0x10100000L EVP_CIPHER_CTX *ctx = em->per_thread_data[thread_index].encrypt_ctx; #else EVP_CIPHER_CTX *ctx = &(em->per_thread_data[thread_index].encrypt_ctx); #endif const EVP_CIPHER *cipher = NULL; int out_len; ASSERT (alg < IPSEC_CRYPTO_N_ALG); if (PREDICT_FALSE (em->ipsec_proto_main_crypto_algs[alg].type == IPSEC_CRYPTO_ALG_NONE)) return; if (PREDICT_FALSE (alg != em->per_thread_data[thread_index].last_encrypt_alg)) { cipher = em->ipsec_proto_main_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; ipsec_proto_main_t *em = &ipsec_proto_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 = 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 = 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[em-> ipsec_proto_main_crypto_algs[sa0->crypto_alg].iv_size]; RAND_bytes (iv, sizeof (iv)); clib_memcpy ((u8 *) vlib_buffer_get_current (o_b0) + ip_hdr_size + sizeof (esp_header_t), iv, em->ipsec_proto_main_crypto_algs[sa0-> crypto_alg].iv_size); esp_encrypt_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: */