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Diffstat (limited to 'src/vnet/ipsec/esp_encrypt.c')
-rw-r--r--src/vnet/ipsec/esp_encrypt.c425
1 files changed, 425 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..7b7f9b9c
--- /dev/null
+++ b/src/vnet/ipsec/esp_encrypt.c
@@ -0,0 +1,425 @@
+/*
+ * 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 cpu_index = os_get_cpu_number ();
+ EVP_CIPHER_CTX *ctx = &(em->per_thread_data[cpu_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[cpu_index].last_encrypt_alg))
+ {
+ cipher = em->esp_crypto_algs[alg].type;
+ em->per_thread_data[cpu_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 cpu_index = os_get_cpu_number ();
+
+ ipsec_alloc_empty_buffers (vm, im);
+
+ u32 *empty_buffers = im->empty_buffers[cpu_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;
+ }
+
+ /* 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:
+ */