wireguard: initial implementation of wireguard protocol

Type: feature

The main information about plugin you can see in README.md

vpp# wireguard ?
  wireguard create                         wireguard create listen-port <port> private-key <key> src <IP> [generate-key]
  wireguard delete                         wireguard delete <interface>
  wireguard peer add                       wireguard peer add <wg_int> public-key <pub_key_other>endpoint <ip4_dst> allowed-ip <prefix>dst-port [port_dst] persistent-keepalive [keepalive_interval]
  wireguard peer remove                    wireguard peer remove <index>

Change-Id: I85eb0bfc033ccfb2045696398d8a108b1c64b8d9
Signed-off-by: Artem Glazychev <artem.glazychev@xored.com>
Signed-off-by: Damjan Marion <damarion@cisco.com>
Signed-off-by: Jim Thompson <jim@netgate.com>
Signed-off-by: Neale Ranns <nranns@cisco.com>
Signed-off-by: Damjan Marion <damarion@cisco.com>

1 files changed, 257 insertions, 0 deletions

diff --git a/src/plugins/wireguard/wireguard_output_tun.c b/src/plugins/wireguard/wireguard_output_tun.c
new file mode 100755
index 00000000000..daec7a4a2f1
--- /dev/null
+++ b/src/plugins/wireguard/wireguard_output_tun.c
@@ -0,0 +1,257 @@
+/*
+ * Copyright (c) 2020 Doc.ai 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 <vlib/vlib.h>
+#include <vnet/vnet.h>
+#include <vnet/pg/pg.h>
+#include <vnet/fib/ip6_fib.h>
+#include <vnet/fib/ip4_fib.h>
+#include <vnet/fib/fib_entry.h>
+#include <vppinfra/error.h>
+
+#include <wireguard/wireguard.h>
+#include <wireguard/wireguard_send.h>
+
+#define foreach_wg_output_error                                         \
+ _(NONE, "No error")							\
+ _(PEER, "Peer error")                                                  \
+ _(KEYPAIR, "Keypair error")                                            \
+ _(HANDSHAKE_SEND, "Handshake sending failed")                          \
+ _(TOO_BIG, "packet too big")                                           \
+
+#define WG_OUTPUT_SCRATCH_SIZE 2048
+
+typedef struct wg_output_scratch_t_
+{
+  u8 scratch[WG_OUTPUT_SCRATCH_SIZE];
+} wg_output_scratch_t;
+
+/* Cache line aligned per-thread scratch space */
+static wg_output_scratch_t *wg_output_scratchs;
+
+typedef enum
+{
+#define _(sym,str) WG_OUTPUT_ERROR_##sym,
+  foreach_wg_output_error
+#undef _
+    WG_OUTPUT_N_ERROR,
+} wg_output_error_t;
+
+static char *wg_output_error_strings[] = {
+#define _(sym,string) string,
+  foreach_wg_output_error
+#undef _
+};
+
+typedef enum
+{
+  WG_OUTPUT_NEXT_ERROR,
+  WG_OUTPUT_NEXT_INTERFACE_OUTPUT,
+  WG_OUTPUT_N_NEXT,
+} wg_output_next_t;
+
+typedef struct
+{
+  ip4_udp_header_t hdr;
+} wg_output_tun_trace_t;
+
+u8 *
+format_ip4_udp_header (u8 * s, va_list * args)
+{
+  ip4_udp_header_t *hdr = va_arg (*args, ip4_udp_header_t *);
+
+  s = format (s, "%U:$U",
+	      format_ip4_header, &hdr->ip4, format_udp_header, &hdr->udp);
+
+  return (s);
+}
+
+/* packet trace format function */
+static u8 *
+format_wg_output_tun_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 *);
+
+  wg_output_tun_trace_t *t = va_arg (*args, wg_output_tun_trace_t *);
+
+  s = format (s, "Encrypted packet: %U\n", format_ip4_udp_header, &t->hdr);
+  return s;
+}
+
+VLIB_NODE_FN (wg_output_tun_node) (vlib_main_t * vm,
+				   vlib_node_runtime_t * node,
+				   vlib_frame_t * frame)
+{
+  u32 n_left_from;
+  u32 *from;
+  vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
+  u16 nexts[VLIB_FRAME_SIZE], *next;
+  u32 thread_index = vm->thread_index;
+
+  from = vlib_frame_vector_args (frame);
+  n_left_from = frame->n_vectors;
+  b = bufs;
+  next = nexts;
+
+  vlib_get_buffers (vm, from, bufs, n_left_from);
+
+  wg_main_t *wmp = &wg_main;
+  u32 handsh_fails = 0;
+  wg_peer_t *peer = NULL;
+
+  while (n_left_from > 0)
+    {
+      ip4_udp_header_t *hdr = vlib_buffer_get_current (b[0]);
+      u8 *plain_data = vlib_buffer_get_current (b[0]) + sizeof (ip4_header_t);
+      u16 plain_data_len =
+	clib_net_to_host_u16 (((ip4_header_t *) plain_data)->length);
+
+      next[0] = WG_OUTPUT_NEXT_ERROR;
+
+      peer =
+	wg_peer_get_by_adj_index (vnet_buffer (b[0])->ip.adj_index[VLIB_TX]);
+
+      if (!peer || peer->is_dead)
+	{
+	  b[0]->error = node->errors[WG_OUTPUT_ERROR_PEER];
+	  goto out;
+	}
+
+      if (PREDICT_FALSE (!peer->remote.r_current))
+	{
+	  if (PREDICT_FALSE (!wg_send_handshake (vm, peer, false)))
+	    handsh_fails++;
+	  b[0]->error = node->errors[WG_OUTPUT_ERROR_KEYPAIR];
+	  goto out;
+	}
+
+      size_t encrypted_packet_len = message_data_len (plain_data_len);
+
+      /*
+       * Ensure there is enough space to write the encrypted data
+       * into the packet
+       */
+      if (PREDICT_FALSE (encrypted_packet_len > WG_OUTPUT_SCRATCH_SIZE) ||
+	  PREDICT_FALSE ((b[0]->current_data + encrypted_packet_len) <
+			 vlib_buffer_get_default_data_size (vm)))
+	{
+	  b[0]->error = node->errors[WG_OUTPUT_ERROR_TOO_BIG];
+	  goto out;
+	}
+
+      message_data_t *encrypted_packet =
+	(message_data_t *) wg_output_scratchs[thread_index].scratch;
+
+      enum noise_state_crypt state;
+      state =
+	noise_remote_encrypt (wmp->vlib_main,
+			      &peer->remote,
+			      &encrypted_packet->receiver_index,
+			      &encrypted_packet->counter, plain_data,
+			      plain_data_len,
+			      encrypted_packet->encrypted_data);
+      switch (state)
+	{
+	case SC_OK:
+	  break;
+	case SC_KEEP_KEY_FRESH:
+	  if (PREDICT_FALSE (!wg_send_handshake (vm, peer, false)))
+	    handsh_fails++;
+	  break;
+	case SC_FAILED:
+	  //TODO: Maybe wrong
+	  if (PREDICT_FALSE (!wg_send_handshake (vm, peer, false)))
+	    handsh_fails++;
+	  clib_mem_free (encrypted_packet);
+	  goto out;
+	default:
+	  break;
+	}
+
+      // Here we are sure that can send packet to next node.
+      next[0] = WG_OUTPUT_NEXT_INTERFACE_OUTPUT;
+      encrypted_packet->header.type = MESSAGE_DATA;
+
+      clib_memcpy (plain_data, (u8 *) encrypted_packet, encrypted_packet_len);
+
+      hdr->udp.length = clib_host_to_net_u16 (encrypted_packet_len +
+					      sizeof (udp_header_t));
+      b[0]->current_length = (encrypted_packet_len +
+			      sizeof (ip4_header_t) + sizeof (udp_header_t));
+      ip4_header_set_len_w_chksum
+	(&hdr->ip4, clib_host_to_net_u16 (b[0]->current_length));
+
+      wg_timers_any_authenticated_packet_traversal (peer);
+      wg_timers_any_authenticated_packet_sent (peer);
+      wg_timers_data_sent (peer);
+
+    out:
+      if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
+			 && (b[0]->flags & VLIB_BUFFER_IS_TRACED)))
+	{
+	  wg_output_tun_trace_t *t =
+	    vlib_add_trace (vm, node, b[0], sizeof (*t));
+	  t->hdr = *hdr;
+	}
+      n_left_from -= 1;
+      next += 1;
+      b += 1;
+    }
+
+  vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
+
+  vlib_node_increment_counter (vm, node->node_index,
+			       WG_OUTPUT_ERROR_HANDSHAKE_SEND, handsh_fails);
+
+  return frame->n_vectors;
+}
+
+/* *INDENT-OFF* */
+VLIB_REGISTER_NODE (wg_output_tun_node) =
+{
+  .name = "wg-output-tun",
+  .vector_size = sizeof (u32),
+  .format_trace = format_wg_output_tun_trace,
+  .type = VLIB_NODE_TYPE_INTERNAL,
+  .n_errors = ARRAY_LEN (wg_output_error_strings),
+  .error_strings = wg_output_error_strings,
+  .n_next_nodes = WG_OUTPUT_N_NEXT,
+  .next_nodes = {
+        [WG_OUTPUT_NEXT_INTERFACE_OUTPUT] = "adj-midchain-tx",
+        [WG_OUTPUT_NEXT_ERROR] = "error-drop",
+  },
+};
+/* *INDENT-ON* */
+
+static clib_error_t *
+wireguard_output_module_init (vlib_main_t * vm)
+{
+  vlib_thread_main_t *tm = vlib_get_thread_main ();
+
+  vec_validate_aligned (wg_output_scratchs, tm->n_vlib_mains,
+			CLIB_CACHE_LINE_BYTES);
+  return (NULL);
+}
+
+VLIB_INIT_FUNCTION (wireguard_output_module_init);
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */