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, 418 insertions, 0 deletions

diff --git a/src/plugins/wireguard/wireguard_peer.c b/src/plugins/wireguard/wireguard_peer.c
new file mode 100755
index 00000000000..0dcc4e20e41
--- /dev/null
+++ b/src/plugins/wireguard/wireguard_peer.c
@@ -0,0 +1,418 @@
+/*
+ * 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 <vnet/adj/adj_midchain.h>
+#include <vnet/fib/fib_table.h>
+#include <wireguard/wireguard_peer.h>
+#include <wireguard/wireguard_if.h>
+#include <wireguard/wireguard_messages.h>
+#include <wireguard/wireguard_key.h>
+#include <wireguard/wireguard_send.h>
+#include <wireguard/wireguard.h>
+
+static fib_source_t wg_fib_source;
+
+index_t *wg_peer_by_adj_index;
+
+wg_peer_t *
+wg_peer_get (index_t peeri)
+{
+  return (pool_elt_at_index (wg_main.peers, peeri));
+}
+
+static void
+wg_peer_endpoint_reset (wg_peer_endpoint_t * ep)
+{
+  ip46_address_reset (&ep->addr);
+  ep->port = 0;
+}
+
+static void
+wg_peer_endpoint_init (wg_peer_endpoint_t * ep,
+		       const ip46_address_t * addr, u16 port)
+{
+  ip46_address_copy (&ep->addr, addr);
+  ep->port = port;
+}
+
+static void
+wg_peer_fib_flush (wg_peer_t * peer)
+{
+  wg_peer_allowed_ip_t *allowed_ip;
+
+  vec_foreach (allowed_ip, peer->allowed_ips)
+  {
+    fib_table_entry_delete_index (allowed_ip->fib_entry_index, wg_fib_source);
+    allowed_ip->fib_entry_index = FIB_NODE_INDEX_INVALID;
+  }
+}
+
+static void
+wg_peer_fib_populate (wg_peer_t * peer, u32 fib_index)
+{
+  wg_peer_allowed_ip_t *allowed_ip;
+
+  vec_foreach (allowed_ip, peer->allowed_ips)
+  {
+    allowed_ip->fib_entry_index =
+      fib_table_entry_path_add (fib_index,
+				&allowed_ip->prefix,
+				wg_fib_source,
+				FIB_ENTRY_FLAG_NONE,
+				fib_proto_to_dpo (allowed_ip->
+						  prefix.fp_proto),
+				&peer->dst.addr, peer->wg_sw_if_index, ~0, 1,
+				NULL, FIB_ROUTE_PATH_FLAG_NONE);
+  }
+}
+
+static void
+wg_peer_clear (vlib_main_t * vm, wg_peer_t * peer)
+{
+  wg_timers_stop (peer);
+  noise_remote_clear (vm, &peer->remote);
+  peer->last_sent_handshake = vlib_time_now (vm) - (REKEY_TIMEOUT + 1);
+
+  clib_memset (&peer->cookie_maker, 0, sizeof (peer->cookie_maker));
+
+  wg_peer_endpoint_reset (&peer->src);
+  wg_peer_endpoint_reset (&peer->dst);
+
+  if (INDEX_INVALID != peer->adj_index)
+    {
+      adj_unlock (peer->adj_index);
+      wg_peer_by_adj_index[peer->adj_index] = INDEX_INVALID;
+    }
+  wg_peer_fib_flush (peer);
+
+  peer->adj_index = INDEX_INVALID;
+  peer->persistent_keepalive_interval = 0;
+  peer->timer_handshake_attempts = 0;
+  peer->timer_need_another_keepalive = false;
+  peer->is_dead = true;
+  vec_free (peer->allowed_ips);
+}
+
+static void
+wg_peer_init (vlib_main_t * vm, wg_peer_t * peer)
+{
+  wg_timers_init (peer, vlib_time_now (vm));
+  wg_peer_clear (vm, peer);
+}
+
+static u8 *
+wg_peer_build_rewrite (const wg_peer_t * peer)
+{
+  // v4 only for now
+  ip4_udp_header_t *hdr;
+  u8 *rewrite = NULL;
+
+  vec_validate (rewrite, sizeof (*hdr) - 1);
+  hdr = (ip4_udp_header_t *) rewrite;
+
+  hdr->ip4.ip_version_and_header_length = 0x45;
+  hdr->ip4.ttl = 64;
+  hdr->ip4.src_address = peer->src.addr.ip4;
+  hdr->ip4.dst_address = peer->dst.addr.ip4;
+  hdr->ip4.protocol = IP_PROTOCOL_UDP;
+  hdr->ip4.checksum = ip4_header_checksum (&hdr->ip4);
+
+  hdr->udp.src_port = clib_host_to_net_u16 (peer->src.port);
+  hdr->udp.dst_port = clib_host_to_net_u16 (peer->dst.port);
+  hdr->udp.checksum = 0;
+
+  return (rewrite);
+}
+
+static void
+wg_peer_adj_stack (wg_peer_t * peer)
+{
+  ip_adjacency_t *adj;
+  u32 sw_if_index;
+  wg_if_t *wgi;
+
+  adj = adj_get (peer->adj_index);
+  sw_if_index = adj->rewrite_header.sw_if_index;
+
+  wgi = wg_if_get (wg_if_find_by_sw_if_index (sw_if_index));
+
+  if (!wgi)
+    return;
+
+  if (!vnet_sw_interface_is_admin_up (vnet_get_main (), wgi->sw_if_index))
+    {
+      adj_midchain_delegate_unstack (peer->adj_index);
+    }
+  else
+    {
+      /* *INDENT-OFF* */
+      fib_prefix_t dst = {
+        .fp_len = 32,
+        .fp_proto = FIB_PROTOCOL_IP4,
+        .fp_addr = peer->dst.addr,
+      };
+      /* *INDENT-ON* */
+      u32 fib_index;
+
+      fib_index = fib_table_find (FIB_PROTOCOL_IP4, peer->table_id);
+
+      adj_midchain_delegate_stack (peer->adj_index, fib_index, &dst);
+    }
+}
+
+walk_rc_t
+wg_peer_if_admin_state_change (wg_if_t * wgi, index_t peeri, void *data)
+{
+  wg_peer_adj_stack (wg_peer_get (peeri));
+
+  return (WALK_CONTINUE);
+}
+
+walk_rc_t
+wg_peer_if_table_change (wg_if_t * wgi, index_t peeri, void *data)
+{
+  wg_peer_table_bind_ctx_t *ctx = data;
+  wg_peer_t *peer;
+
+  peer = wg_peer_get (peeri);
+
+  wg_peer_fib_flush (peer);
+  wg_peer_fib_populate (peer, ctx->new_fib_index);
+
+  return (WALK_CONTINUE);
+}
+
+static int
+wg_peer_fill (vlib_main_t * vm, wg_peer_t * peer,
+	      u32 table_id,
+	      const ip46_address_t * dst,
+	      u16 port,
+	      u16 persistent_keepalive_interval,
+	      const fib_prefix_t * allowed_ips, u32 wg_sw_if_index)
+{
+  wg_peer_endpoint_init (&peer->dst, dst, port);
+
+  peer->table_id = table_id;
+  peer->persistent_keepalive_interval = persistent_keepalive_interval;
+  peer->wg_sw_if_index = wg_sw_if_index;
+  peer->last_sent_handshake = vlib_time_now (vm) - (REKEY_TIMEOUT + 1);
+  peer->is_dead = false;
+
+  const wg_if_t *wgi = wg_if_get (wg_if_find_by_sw_if_index (wg_sw_if_index));
+
+  if (NULL == wgi)
+    return (VNET_API_ERROR_INVALID_INTERFACE);
+
+  ip_address_to_46 (&wgi->src_ip, &peer->src.addr);
+  peer->src.port = wgi->port;
+
+  /*
+   * and an adjacency for the endpoint address in the overlay
+   * on the wg interface
+   */
+  peer->rewrite = wg_peer_build_rewrite (peer);
+
+  peer->adj_index = adj_nbr_add_or_lock (FIB_PROTOCOL_IP4,
+					 VNET_LINK_IP4,
+					 &peer->dst.addr, wgi->sw_if_index);
+
+  vec_validate_init_empty (wg_peer_by_adj_index,
+			   peer->adj_index, INDEX_INVALID);
+  wg_peer_by_adj_index[peer->adj_index] = peer - wg_main.peers;
+
+  adj_nbr_midchain_update_rewrite (peer->adj_index,
+				   NULL,
+				   NULL,
+				   ADJ_FLAG_MIDCHAIN_IP_STACK,
+				   vec_dup (peer->rewrite));
+  wg_peer_adj_stack (peer);
+
+  /*
+   * add a route in the overlay to each of the allowed-ips
+   */
+  u32 ii;
+
+  vec_validate (peer->allowed_ips, vec_len (allowed_ips) - 1);
+
+  vec_foreach_index (ii, allowed_ips)
+  {
+    peer->allowed_ips[ii].prefix = allowed_ips[ii];
+  }
+
+  wg_peer_fib_populate (peer,
+			fib_table_get_index_for_sw_if_index
+			(FIB_PROTOCOL_IP4, peer->wg_sw_if_index));
+
+  return (0);
+}
+
+int
+wg_peer_add (u32 tun_sw_if_index,
+	     const u8 public_key[NOISE_PUBLIC_KEY_LEN],
+	     u32 table_id,
+	     const ip46_address_t * endpoint,
+	     const fib_prefix_t * allowed_ips,
+	     u16 port, u16 persistent_keepalive, u32 * peer_index)
+{
+  wg_if_t *wg_if;
+  wg_peer_t *peer;
+  int rv;
+
+  vlib_main_t *vm = vlib_get_main ();
+
+  if (tun_sw_if_index == ~0)
+    return (VNET_API_ERROR_INVALID_SW_IF_INDEX);
+
+  wg_if = wg_if_get (wg_if_find_by_sw_if_index (tun_sw_if_index));
+  if (!wg_if)
+    return (VNET_API_ERROR_INVALID_SW_IF_INDEX);
+
+  /* *INDENT-OFF* */
+  pool_foreach (peer, wg_main.peers,
+  ({
+    if (!memcmp (peer->remote.r_public, public_key, NOISE_PUBLIC_KEY_LEN))
+    {
+      return (VNET_API_ERROR_ENTRY_ALREADY_EXISTS);
+    }
+  }));
+  /* *INDENT-ON* */
+
+  if (pool_elts (wg_main.peers) > MAX_PEERS)
+    return (VNET_API_ERROR_LIMIT_EXCEEDED);
+
+  pool_get (wg_main.peers, peer);
+
+  wg_peer_init (vm, peer);
+
+  rv = wg_peer_fill (vm, peer, table_id, endpoint, (u16) port,
+		     persistent_keepalive, allowed_ips, tun_sw_if_index);
+
+  if (rv)
+    {
+      wg_peer_clear (vm, peer);
+      pool_put (wg_main.peers, peer);
+      return (rv);
+    }
+
+  noise_remote_init (&peer->remote, peer - wg_main.peers, public_key,
+		     &wg_if->local);
+  cookie_maker_init (&peer->cookie_maker, public_key);
+
+  if (peer->persistent_keepalive_interval != 0)
+    {
+      wg_send_keepalive (vm, peer);
+    }
+
+  *peer_index = peer - wg_main.peers;
+  wg_if_peer_add (wg_if, *peer_index);
+
+  return (0);
+}
+
+int
+wg_peer_remove (index_t peeri)
+{
+  wg_main_t *wmp = &wg_main;
+  wg_peer_t *peer = NULL;
+  wg_if_t *wgi;
+
+  if (pool_is_free_index (wmp->peers, peeri))
+    return VNET_API_ERROR_NO_SUCH_ENTRY;
+
+  peer = pool_elt_at_index (wmp->peers, peeri);
+
+  wgi = wg_if_get (wg_if_find_by_sw_if_index (peer->wg_sw_if_index));
+  wg_if_peer_remove (wgi, peeri);
+
+  vnet_feature_enable_disable ("ip4-output", "wg-output-tun",
+			       peer->wg_sw_if_index, 0, 0, 0);
+  wg_peer_clear (wmp->vlib_main, peer);
+  pool_put (wmp->peers, peer);
+
+  return (0);
+}
+
+void
+wg_peer_walk (wg_peer_walk_cb_t fn, void *data)
+{
+  index_t peeri;
+
+  /* *INDENT-OFF* */
+  pool_foreach_index(peeri, wg_main.peers,
+  {
+    if (WALK_STOP == fn(peeri, data))
+      break;
+  });
+  /* *INDENT-ON* */
+}
+
+static u8 *
+format_wg_peer_endpoint (u8 * s, va_list * args)
+{
+  wg_peer_endpoint_t *ep = va_arg (*args, wg_peer_endpoint_t *);
+
+  s = format (s, "%U:%d",
+	      format_ip46_address, &ep->addr, IP46_TYPE_ANY, ep->port);
+
+  return (s);
+}
+
+u8 *
+format_wg_peer (u8 * s, va_list * va)
+{
+  index_t peeri = va_arg (*va, index_t);
+  wg_peer_allowed_ip_t *allowed_ip;
+  u8 key[NOISE_KEY_LEN_BASE64];
+  wg_peer_t *peer;
+
+  peer = wg_peer_get (peeri);
+  key_to_base64 (peer->remote.r_public, NOISE_PUBLIC_KEY_LEN, key);
+
+  s = format (s, "[%d] key:%=45s endpoint:[%U->%U] %U keep-alive:%d adj:%d",
+	      peeri,
+	      key,
+	      format_wg_peer_endpoint, &peer->src,
+	      format_wg_peer_endpoint, &peer->dst,
+	      format_vnet_sw_if_index_name, vnet_get_main (),
+	      peer->wg_sw_if_index,
+	      peer->persistent_keepalive_interval, peer->adj_index);
+
+  s = format (s, "\n  allowed-ips:");
+  vec_foreach (allowed_ip, peer->allowed_ips)
+  {
+    s = format (s, " %U", format_fib_prefix, &allowed_ip->prefix);
+  }
+
+  return s;
+}
+
+static clib_error_t *
+wg_peer_module_init (vlib_main_t * vm)
+{
+  wg_fib_source = fib_source_allocate ("wireguard", 0xb0,	//
+				       FIB_SOURCE_BH_SIMPLE);
+
+  return (NULL);
+}
+
+VLIB_INIT_FUNCTION (wg_peer_module_init);
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */