tls: add openssl engine

Change-Id: I6c215858d2c9c620787632b570950b15274c0df2
Signed-off-by: Florin Coras <fcoras@cisco.com>

1 files changed, 675 insertions, 0 deletions

diff --git a/src/plugins/tlsopenssl/tls_openssl.c b/src/plugins/tlsopenssl/tls_openssl.c
new file mode 100644
index 00000000000..0817f606ad8
--- /dev/null
+++ b/src/plugins/tlsopenssl/tls_openssl.c
@@ -0,0 +1,675 @@
+/*
+ * Copyright (c) 2018 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 <openssl/ssl.h>
+#include <openssl/conf.h>
+#include <openssl/err.h>
+#include <vnet/plugin/plugin.h>
+#include <vpp/app/version.h>
+#include <vnet/tls/tls.h>
+
+typedef struct tls_ctx_openssl_
+{
+  tls_ctx_t ctx;			/**< First */
+  u32 openssl_ctx_index;
+  SSL_CTX *ssl_ctx;
+  SSL *ssl;
+  BIO *rbio;
+  BIO *wbio;
+  X509 *srvcert;
+  EVP_PKEY *pkey;
+} openssl_ctx_t;
+
+typedef struct openssl_main_
+{
+  openssl_ctx_t ***ctx_pool;
+  X509_STORE *cert_store;
+} openssl_main_t;
+
+static openssl_main_t openssl_main;
+
+static u32
+openssl_ctx_alloc (void)
+{
+  u8 thread_index = vlib_get_thread_index ();
+  openssl_main_t *tm = &openssl_main;
+  openssl_ctx_t **ctx;
+
+  pool_get (tm->ctx_pool[thread_index], ctx);
+  if (!(*ctx))
+    *ctx = clib_mem_alloc (sizeof (openssl_ctx_t));
+
+  memset (*ctx, 0, sizeof (openssl_ctx_t));
+  (*ctx)->ctx.c_thread_index = thread_index;
+  (*ctx)->ctx.tls_ctx_engine = TLS_ENGINE_OPENSSL;
+  (*ctx)->ctx.app_session_handle = SESSION_INVALID_HANDLE;
+  (*ctx)->openssl_ctx_index = ctx - tm->ctx_pool[thread_index];
+  return ((*ctx)->openssl_ctx_index);
+}
+
+static void
+openssl_ctx_free (tls_ctx_t * ctx)
+{
+  openssl_ctx_t *oc = (openssl_ctx_t *) ctx;
+
+  if (SSL_is_init_finished (oc->ssl) && !ctx->is_passive_close)
+    SSL_shutdown (oc->ssl);
+
+  if (SSL_is_server (oc->ssl))
+    {
+      X509_free (oc->srvcert);
+      EVP_PKEY_free (oc->pkey);
+    }
+  SSL_free (oc->ssl);
+
+  pool_put_index (openssl_main.ctx_pool[ctx->c_thread_index],
+		  oc->openssl_ctx_index);
+}
+
+static tls_ctx_t *
+openssl_ctx_get (u32 ctx_index)
+{
+  openssl_ctx_t **ctx;
+  ctx = pool_elt_at_index (openssl_main.ctx_pool[vlib_get_thread_index ()],
+			   ctx_index);
+  return &(*ctx)->ctx;
+}
+
+static tls_ctx_t *
+openssl_ctx_get_w_thread (u32 ctx_index, u8 thread_index)
+{
+  openssl_ctx_t **ctx;
+  ctx = pool_elt_at_index (openssl_main.ctx_pool[thread_index], ctx_index);
+  return &(*ctx)->ctx;
+}
+
+static int
+openssl_try_handshake_read (openssl_ctx_t * oc,
+			    stream_session_t * tls_session)
+{
+  u32 deq_max, deq_now;
+  svm_fifo_t *f;
+  int wrote, rv;
+
+  f = tls_session->server_rx_fifo;
+  deq_max = svm_fifo_max_dequeue (f);
+  if (!deq_max)
+    return 0;
+
+  deq_now = clib_min (svm_fifo_max_read_chunk (f), deq_max);
+  wrote = BIO_write (oc->wbio, svm_fifo_head (f), deq_now);
+  if (wrote <= 0)
+    return 0;
+
+  svm_fifo_dequeue_drop (f, wrote);
+  if (wrote < deq_max)
+    {
+      deq_now = clib_min (svm_fifo_max_read_chunk (f), deq_max - wrote);
+      rv = BIO_write (oc->wbio, svm_fifo_head (f), deq_now);
+      if (rv > 0)
+	{
+	  svm_fifo_dequeue_drop (f, rv);
+	  wrote += rv;
+	}
+    }
+  return wrote;
+}
+
+static int
+openssl_try_handshake_write (openssl_ctx_t * oc,
+			     stream_session_t * tls_session)
+{
+  u32 enq_max, deq_now;
+  svm_fifo_t *f;
+  int read, rv;
+
+  if (BIO_ctrl_pending (oc->rbio) <= 0)
+    return 0;
+
+  f = tls_session->server_tx_fifo;
+  enq_max = svm_fifo_max_enqueue (f);
+  if (!enq_max)
+    return 0;
+
+  deq_now = clib_min (svm_fifo_max_write_chunk (f), enq_max);
+  read = BIO_read (oc->rbio, svm_fifo_tail (f), deq_now);
+  if (read <= 0)
+    return 0;
+
+  svm_fifo_enqueue_nocopy (f, read);
+  tls_add_vpp_q_evt (f, FIFO_EVENT_APP_TX);
+
+  if (read < enq_max)
+    {
+      deq_now = clib_min (svm_fifo_max_write_chunk (f), enq_max - read);
+      rv = BIO_read (oc->rbio, svm_fifo_tail (f), deq_now);
+      if (rv > 0)
+	{
+	  svm_fifo_enqueue_nocopy (f, rv);
+	  read += rv;
+	}
+    }
+
+  return read;
+}
+
+static int
+openssl_ctx_handshake_rx (tls_ctx_t * ctx, stream_session_t * tls_session)
+{
+  openssl_ctx_t *oc = (openssl_ctx_t *) ctx;
+  int rv = 0, err;
+  while (SSL_in_init (oc->ssl))
+    {
+      if (!openssl_try_handshake_read (oc, tls_session))
+	break;
+
+      rv = SSL_do_handshake (oc->ssl);
+      err = SSL_get_error (oc->ssl, rv);
+      openssl_try_handshake_write (oc, tls_session);
+      if (err != SSL_ERROR_WANT_WRITE)
+	{
+	  if (err == SSL_ERROR_SSL)
+	    {
+	      char buf[512];
+	      ERR_error_string (ERR_get_error (), buf);
+	      clib_warning ("Err: %s", buf);
+	    }
+	  break;
+	}
+    }
+  TLS_DBG (2, "tls state for %u is %s", oc->openssl_ctx_index,
+	   SSL_state_string_long (oc->ssl));
+
+  if (SSL_in_init (oc->ssl))
+    return 0;
+
+  /*
+   * Handshake complete
+   */
+  if (!SSL_is_server (oc->ssl))
+    {
+      /*
+       * Verify server certificate
+       */
+      if ((rv = SSL_get_verify_result (oc->ssl)) != X509_V_OK)
+	{
+	  TLS_DBG (1, " failed verify: %s\n",
+		   X509_verify_cert_error_string (rv));
+
+	  /*
+	   * Presence of hostname enforces strict certificate verification
+	   */
+	  if (ctx->srv_hostname)
+	    {
+	      tls_notify_app_connected (ctx, /* is failed */ 0);
+	      return -1;
+	    }
+	}
+      tls_notify_app_connected (ctx, /* is failed */ 0);
+    }
+  else
+    {
+      tls_notify_app_accept (ctx);
+    }
+
+  TLS_DBG (1, "Handshake for %u complete. TLS cipher is %s",
+	   oc->openssl_ctx_index, SSL_get_cipher (oc->ssl));
+  return rv;
+}
+
+static inline int
+openssl_ctx_write (tls_ctx_t * ctx, stream_session_t * app_session)
+{
+  openssl_ctx_t *oc = (openssl_ctx_t *) ctx;
+  int wrote = 0, rv, read, max_buf = 100 * TLS_CHUNK_SIZE, max_space;
+  u32 enq_max, deq_max, deq_now, to_write;
+  stream_session_t *tls_session;
+  svm_fifo_t *f;
+
+  f = app_session->server_tx_fifo;
+  deq_max = svm_fifo_max_dequeue (f);
+  if (!deq_max)
+    goto check_tls_fifo;
+
+  max_space = max_buf - BIO_ctrl_pending (oc->rbio);
+  max_space = (max_space < 0) ? 0 : max_space;
+  deq_now = clib_min (deq_max, (u32) max_space);
+  to_write = clib_min (svm_fifo_max_read_chunk (f), deq_now);
+  wrote = SSL_write (oc->ssl, svm_fifo_head (f), to_write);
+  if (wrote <= 0)
+    {
+      tls_add_vpp_q_evt (app_session->server_tx_fifo, FIFO_EVENT_APP_TX);
+      goto check_tls_fifo;
+    }
+  svm_fifo_dequeue_drop (app_session->server_tx_fifo, wrote);
+  if (wrote < deq_now)
+    {
+      to_write = clib_min (svm_fifo_max_read_chunk (f), deq_now - wrote);
+      rv = SSL_write (oc->ssl, svm_fifo_head (f), to_write);
+      if (rv > 0)
+	{
+	  svm_fifo_dequeue_drop (app_session->server_tx_fifo, rv);
+	  wrote += rv;
+	}
+    }
+
+  if (deq_now < deq_max)
+    tls_add_vpp_q_evt (app_session->server_tx_fifo, FIFO_EVENT_APP_TX);
+
+check_tls_fifo:
+
+  if (BIO_ctrl_pending (oc->rbio) <= 0)
+    return wrote;
+
+  tls_session = session_get_from_handle (ctx->tls_session_handle);
+  f = tls_session->server_tx_fifo;
+  enq_max = svm_fifo_max_enqueue (f);
+  if (!enq_max)
+    {
+      tls_add_vpp_q_evt (app_session->server_tx_fifo, FIFO_EVENT_APP_TX);
+      return wrote;
+    }
+
+  deq_now = clib_min (svm_fifo_max_write_chunk (f), enq_max);
+  read = BIO_read (oc->rbio, svm_fifo_tail (f), deq_now);
+  if (read <= 0)
+    {
+      tls_add_vpp_q_evt (app_session->server_tx_fifo, FIFO_EVENT_APP_TX);
+      return wrote;
+    }
+
+  svm_fifo_enqueue_nocopy (f, read);
+  tls_add_vpp_q_evt (f, FIFO_EVENT_APP_TX);
+
+  if (read < enq_max && BIO_ctrl_pending (oc->rbio) > 0)
+    {
+      deq_now = clib_min (svm_fifo_max_write_chunk (f), enq_max - read);
+      read = BIO_read (oc->rbio, svm_fifo_tail (f), deq_now);
+      if (read > 0)
+	svm_fifo_enqueue_nocopy (f, read);
+    }
+
+  if (BIO_ctrl_pending (oc->rbio) > 0)
+    tls_add_vpp_q_evt (app_session->server_tx_fifo, FIFO_EVENT_APP_TX);
+
+  return wrote;
+}
+
+static inline int
+openssl_ctx_read (tls_ctx_t * ctx, stream_session_t * tls_session)
+{
+  int read, wrote = 0, max_space, max_buf = 100 * TLS_CHUNK_SIZE, rv;
+  openssl_ctx_t *oc = (openssl_ctx_t *) ctx;
+  u32 deq_max, enq_max, deq_now, to_read;
+  stream_session_t *app_session;
+  svm_fifo_t *f;
+
+  if (PREDICT_FALSE (SSL_in_init (oc->ssl)))
+    {
+      openssl_ctx_handshake_rx (ctx, tls_session);
+      return 0;
+    }
+
+  f = tls_session->server_rx_fifo;
+  deq_max = svm_fifo_max_dequeue (f);
+  max_space = max_buf - BIO_ctrl_pending (oc->wbio);
+  max_space = max_space < 0 ? 0 : max_space;
+  deq_now = clib_min (deq_max, max_space);
+  if (!deq_now)
+    goto check_app_fifo;
+
+  to_read = clib_min (svm_fifo_max_read_chunk (f), deq_now);
+  wrote = BIO_write (oc->wbio, svm_fifo_head (f), to_read);
+  if (wrote <= 0)
+    {
+      tls_add_vpp_q_evt (tls_session->server_rx_fifo, FIFO_EVENT_BUILTIN_RX);
+      goto check_app_fifo;
+    }
+  svm_fifo_dequeue_drop (f, wrote);
+  if (wrote < deq_now)
+    {
+      to_read = clib_min (svm_fifo_max_read_chunk (f), deq_now - wrote);
+      rv = BIO_write (oc->wbio, svm_fifo_head (f), to_read);
+      if (rv > 0)
+	{
+	  svm_fifo_dequeue_drop (f, rv);
+	  wrote += rv;
+	}
+    }
+  if (svm_fifo_max_dequeue (f))
+    tls_add_vpp_q_evt (tls_session->server_rx_fifo, FIFO_EVENT_BUILTIN_RX);
+
+check_app_fifo:
+
+  if (BIO_ctrl_pending (oc->wbio) <= 0)
+    return wrote;
+
+  app_session = session_get_from_handle (ctx->app_session_handle);
+  f = app_session->server_rx_fifo;
+  enq_max = svm_fifo_max_enqueue (f);
+  if (!enq_max)
+    {
+      tls_add_vpp_q_evt (tls_session->server_rx_fifo, FIFO_EVENT_BUILTIN_RX);
+      return wrote;
+    }
+
+  deq_now = clib_min (svm_fifo_max_write_chunk (f), enq_max);
+  read = SSL_read (oc->ssl, svm_fifo_tail (f), deq_now);
+  if (read <= 0)
+    {
+      tls_add_vpp_q_evt (tls_session->server_rx_fifo, FIFO_EVENT_BUILTIN_RX);
+      return wrote;
+    }
+  svm_fifo_enqueue_nocopy (f, read);
+  if (read < enq_max && BIO_ctrl_pending (oc->wbio) > 0)
+    {
+      deq_now = clib_min (svm_fifo_max_write_chunk (f), enq_max - read);
+      read = SSL_read (oc->ssl, svm_fifo_tail (f), deq_now);
+      if (read > 0)
+	svm_fifo_enqueue_nocopy (f, read);
+    }
+
+  tls_notify_app_enqueue (ctx, app_session);
+  if (BIO_ctrl_pending (oc->wbio) > 0)
+    tls_add_vpp_q_evt (tls_session->server_rx_fifo, FIFO_EVENT_BUILTIN_RX);
+
+  return wrote;
+}
+
+static int
+openssl_ctx_init_client (tls_ctx_t * ctx)
+{
+  char *ciphers = "ALL:!ADH:!LOW:!EXP:!MD5:!RC4-SHA:!DES-CBC3-SHA:@STRENGTH";
+  long flags = SSL_OP_NO_SSLv2 | SSL_OP_NO_SSLv3 | SSL_OP_NO_COMPRESSION;
+  openssl_ctx_t *oc = (openssl_ctx_t *) ctx;
+  openssl_main_t *om = &openssl_main;
+  stream_session_t *tls_session;
+  const SSL_METHOD *method;
+  int rv, err;
+
+  method = SSLv23_client_method ();
+  if (method == NULL)
+    {
+      TLS_DBG (1, "SSLv23_method returned null");
+      return -1;
+    }
+
+  oc->ssl_ctx = SSL_CTX_new (method);
+  if (oc->ssl_ctx == NULL)
+    {
+      TLS_DBG (1, "SSL_CTX_new returned null");
+      return -1;
+    }
+
+  SSL_CTX_set_ecdh_auto (oc->ssl_ctx, 1);
+  SSL_CTX_set_mode (oc->ssl_ctx, SSL_MODE_ENABLE_PARTIAL_WRITE);
+  rv = SSL_CTX_set_cipher_list (oc->ssl_ctx, (const char *) ciphers);
+  if (rv != 1)
+    {
+      TLS_DBG (1, "Couldn't set cipher");
+      return -1;
+    }
+
+  SSL_CTX_set_options (oc->ssl_ctx, flags);
+  SSL_CTX_set_cert_store (oc->ssl_ctx, om->cert_store);
+
+  oc->ssl = SSL_new (oc->ssl_ctx);
+  if (oc->ssl == NULL)
+    {
+      TLS_DBG (1, "Couldn't initialize ssl struct");
+      return -1;
+    }
+
+  oc->rbio = BIO_new (BIO_s_mem ());
+  oc->wbio = BIO_new (BIO_s_mem ());
+
+  BIO_set_mem_eof_return (oc->rbio, -1);
+  BIO_set_mem_eof_return (oc->wbio, -1);
+
+  SSL_set_bio (oc->ssl, oc->wbio, oc->rbio);
+  SSL_set_connect_state (oc->ssl);
+
+  rv = SSL_set_tlsext_host_name (oc->ssl, ctx->srv_hostname);
+  if (rv != 1)
+    {
+      TLS_DBG (1, "Couldn't set hostname");
+      return -1;
+    }
+
+  /*
+   * 2. Do the first steps in the handshake.
+   */
+  TLS_DBG (1, "Initiating handshake for [%u]%u", ctx->c_thread_index,
+	   oc->openssl_ctx_index);
+
+  tls_session = session_get_from_handle (ctx->tls_session_handle);
+  while (1)
+    {
+      rv = SSL_do_handshake (oc->ssl);
+      err = SSL_get_error (oc->ssl, rv);
+      openssl_try_handshake_write (oc, tls_session);
+      if (err != SSL_ERROR_WANT_WRITE)
+	break;
+    }
+
+  TLS_DBG (2, "tls state for [%u]%u is su", ctx->c_thread_index,
+	   oc->openssl_ctx_index, SSL_state_string_long (oc->ssl));
+  return 0;
+}
+
+static int
+openssl_ctx_init_server (tls_ctx_t * ctx)
+{
+  char *ciphers = "ALL:!ADH:!LOW:!EXP:!MD5:!RC4-SHA:!DES-CBC3-SHA:@STRENGTH";
+  long flags = SSL_OP_NO_SSLv2 | SSL_OP_NO_SSLv3 | SSL_OP_NO_COMPRESSION;
+  openssl_ctx_t *oc = (openssl_ctx_t *) ctx;
+  stream_session_t *tls_session;
+  const SSL_METHOD *method;
+  application_t *app;
+  int rv, err;
+  BIO *cert_bio;
+
+  app = application_get (ctx->parent_app_index);
+  if (!app->tls_cert || !app->tls_key)
+    {
+      TLS_DBG (1, "tls cert and/or key not configured %d",
+	       ctx->parent_app_index);
+      return -1;
+    }
+
+  method = SSLv23_method ();
+  oc->ssl_ctx = SSL_CTX_new (method);
+  if (!oc->ssl_ctx)
+    {
+      clib_warning ("Unable to create SSL context");
+      return -1;
+    }
+
+  SSL_CTX_set_mode (oc->ssl_ctx, SSL_MODE_ENABLE_PARTIAL_WRITE);
+  SSL_CTX_set_options (oc->ssl_ctx, flags);
+  SSL_CTX_set_ecdh_auto (oc->ssl_ctx, 1);
+
+  rv = SSL_CTX_set_cipher_list (oc->ssl_ctx, (const char *) ciphers);
+  if (rv != 1)
+    {
+      TLS_DBG (1, "Couldn't set cipher");
+      return -1;
+    }
+
+  /*
+   * Set the key and cert
+   */
+  cert_bio = BIO_new (BIO_s_mem ());
+  BIO_write (cert_bio, app->tls_cert, vec_len (app->tls_cert));
+  oc->srvcert = PEM_read_bio_X509 (cert_bio, NULL, NULL, NULL);
+  if (!oc->srvcert)
+    {
+      clib_warning ("unable to parse certificate");
+      return -1;
+    }
+  BIO_free (cert_bio);
+  cert_bio = BIO_new (BIO_s_mem ());
+  BIO_write (cert_bio, app->tls_key, vec_len (app->tls_key));
+  oc->pkey = PEM_read_bio_PrivateKey (cert_bio, NULL, NULL, NULL);
+  if (!oc->pkey)
+    {
+      clib_warning ("unable to parse pkey");
+      return -1;
+    }
+
+  BIO_free (cert_bio);
+
+  oc->ssl = SSL_new (oc->ssl_ctx);
+  if (oc->ssl == NULL)
+    {
+      TLS_DBG (1, "Couldn't initialize ssl struct");
+      return -1;
+    }
+
+  oc->rbio = BIO_new (BIO_s_mem ());
+  oc->wbio = BIO_new (BIO_s_mem ());
+
+  BIO_set_mem_eof_return (oc->rbio, -1);
+  BIO_set_mem_eof_return (oc->wbio, -1);
+
+  SSL_set_bio (oc->ssl, oc->wbio, oc->rbio);
+  SSL_set_accept_state (oc->ssl);
+
+  TLS_DBG (1, "Initiating handshake for [%u]%u", ctx->c_thread_index,
+	   oc->openssl_ctx_index);
+
+  tls_session = session_get_from_handle (ctx->tls_session_handle);
+  while (1)
+    {
+      rv = SSL_do_handshake (oc->ssl);
+      err = SSL_get_error (oc->ssl, rv);
+      openssl_try_handshake_write (oc, tls_session);
+      if (err != SSL_ERROR_WANT_WRITE)
+	break;
+    }
+
+  TLS_DBG (2, "tls state for [%u]%u is su", ctx->c_thread_index,
+	   oc->openssl_ctx_index, SSL_state_string_long (oc->ssl));
+  return 0;
+}
+
+static u8
+openssl_handshake_is_over (tls_ctx_t * ctx)
+{
+  openssl_ctx_t *mc = (openssl_ctx_t *) ctx;
+  if (!mc->ssl)
+    return 0;
+  return SSL_is_init_finished (mc->ssl);
+}
+
+const static tls_engine_vft_t openssl_engine = {
+  .ctx_alloc = openssl_ctx_alloc,
+  .ctx_free = openssl_ctx_free,
+  .ctx_get = openssl_ctx_get,
+  .ctx_get_w_thread = openssl_ctx_get_w_thread,
+  .ctx_init_server = openssl_ctx_init_server,
+  .ctx_init_client = openssl_ctx_init_client,
+  .ctx_write = openssl_ctx_write,
+  .ctx_read = openssl_ctx_read,
+  .ctx_handshake_is_over = openssl_handshake_is_over,
+};
+
+int
+tls_init_ca_chain (void)
+{
+  openssl_main_t *om = &openssl_main;
+  tls_main_t *tm = vnet_tls_get_main ();
+  BIO *cert_bio;
+  X509 *testcert;
+  int rv;
+
+  if (access (tm->ca_cert_path, F_OK | R_OK) == -1)
+    {
+      clib_warning ("Could not initialize TLS CA certificates");
+      return -1;
+    }
+
+  if (!(om->cert_store = X509_STORE_new ()))
+    {
+      clib_warning ("failed to create cert store");
+      return -1;
+    }
+
+  rv = X509_STORE_load_locations (om->cert_store, tm->ca_cert_path, 0);
+  if (rv < 0)
+    {
+      clib_warning ("failed to load ca certificate");
+    }
+
+  if (tm->use_test_cert_in_ca)
+    {
+      cert_bio = BIO_new (BIO_s_mem ());
+      BIO_write (cert_bio, test_srv_crt_rsa, test_srv_crt_rsa_len);
+      testcert = PEM_read_bio_X509 (cert_bio, NULL, NULL, NULL);
+      if (!testcert)
+	{
+	  clib_warning ("unable to parse certificate");
+	  return -1;
+	}
+      X509_STORE_add_cert (om->cert_store, testcert);
+      rv = 0;
+    }
+  return (rv < 0 ? -1 : 0);
+}
+
+static clib_error_t *
+tls_openssl_init (vlib_main_t * vm)
+{
+  vlib_thread_main_t *vtm = vlib_get_thread_main ();
+  openssl_main_t *om = &openssl_main;
+  clib_error_t *error;
+  u32 num_threads;
+
+  num_threads = 1 /* main thread */  + vtm->n_threads;
+
+  if ((error = vlib_call_init_function (vm, tls_init)))
+    return error;
+
+  SSL_library_init ();
+  SSL_load_error_strings ();
+
+  if (tls_init_ca_chain ())
+    {
+      clib_warning ("failed to initialize TLS CA chain");
+      return 0;
+    }
+
+  vec_validate (om->ctx_pool, num_threads - 1);
+
+  tls_register_engine (&openssl_engine, TLS_ENGINE_OPENSSL);
+  return 0;
+}
+
+VLIB_INIT_FUNCTION (tls_openssl_init);
+
+/* *INDENT-OFF* */
+VLIB_PLUGIN_REGISTER () = {
+    .version = VPP_BUILD_VER,
+    .description = "openssl based TLS Engine",
+};
+/* *INDENT-ON* */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */