tls: add custom openssl bio

The bio interacts directly with the session so it avoids using an
intermediary mem bio and, implicitly, higher memory consumption and an
extra memcpy.

Type: improvement

Signed-off-by: Florin Coras <fcoras@cisco.com>
Change-Id: Ifb675cfd12df86396a7a738a6cd4d0882c69ad2f

5 files changed, 244 insertions, 184 deletions

diff --git a/src/plugins/tlsopenssl/CMakeLists.txt b/src/plugins/tlsopenssl/CMakeLists.txt
index 8ac36cfe3fd..61d3638a39a 100644
--- a/src/plugins/tlsopenssl/CMakeLists.txt
+++ b/src/plugins/tlsopenssl/CMakeLists.txt
@@ -12,10 +12,11 @@
 # limitations under the License.
 
 include (CheckFunctionExists)
-if(OPENSSL_FOUND)
+if(OPENSSL_FOUND AND OPENSSL_VERSION VERSION_GREATER_EQUAL "1.1.0")
   include_directories(${OPENSSL_INCLUDE_DIR})
   add_vpp_plugin(tlsopenssl
     SOURCES
+    tls_bio.c
     tls_openssl.c
     tls_openssl_api.c
     tls_async.c
diff --git a/src/plugins/tlsopenssl/tls_bio.c b/src/plugins/tlsopenssl/tls_bio.c
new file mode 100644
index 00000000000..5cdedf649a7
--- /dev/null
+++ b/src/plugins/tlsopenssl/tls_bio.c
@@ -0,0 +1,182 @@
+
+/*
+ * Copyright (c) 2020 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/bio.h>
+#include <openssl/err.h>
+#include <vnet/session/session.h>
+#include <vnet/session/application_interface.h>
+
+static inline session_t *
+bio_session (BIO * bio)
+{
+  return session_get_from_handle (pointer_to_uword (BIO_get_data (bio)));
+}
+
+static int
+bio_tls_alloc (BIO * bio)
+{
+  BIO_set_init (bio, 0);
+  BIO_set_data (bio, 0);
+  BIO_set_flags (bio, 0);
+  BIO_set_shutdown (bio, 0);
+  return 1;
+}
+
+static int
+bio_tls_free (BIO * bio)
+{
+  if (!bio)
+    return 0;
+
+  if (BIO_get_shutdown (bio))
+    {
+      if (BIO_get_init (bio))
+	session_close (bio_session (bio));
+      BIO_set_init (bio, 0);
+      BIO_set_flags (bio, 0);
+    }
+
+  return 1;
+}
+
+static int
+bio_tls_read (BIO * b, char *out, int outl)
+{
+  session_t *s;
+  int rv;
+
+  if (PREDICT_FALSE (!out))
+    return 0;
+
+  s = bio_session (b);
+  if (!s)
+    {
+      clib_warning ("no session");
+      errno = EBADFD;
+      return -1;
+    }
+
+  rv = app_recv_stream_raw (s->rx_fifo, (u8 *) out, outl,
+			    0 /* clear evt */ , 0 /* peek */ );
+  if (rv < 0)
+    {
+      BIO_set_retry_read (b);
+      errno = EAGAIN;
+      return -1;
+    }
+
+  if (svm_fifo_is_empty_cons (s->rx_fifo))
+    svm_fifo_unset_event (s->rx_fifo);
+
+  BIO_clear_retry_flags (b);
+
+  return rv;
+}
+
+static int
+bio_tls_write (BIO * b, const char *in, int inl)
+{
+  svm_msg_q_t *mq;
+  session_t *s;
+  int rv;
+
+  if (PREDICT_FALSE (!in))
+    return 0;
+
+  s = bio_session (b);
+  if (!s)
+    {
+      clib_warning ("no session");
+      errno = EBADFD;
+      return -1;
+    }
+
+  mq = session_main_get_vpp_event_queue (s->thread_index);
+  rv = app_send_stream_raw (s->tx_fifo, mq, (u8 *) in, inl,
+			    SESSION_IO_EVT_TX, 1 /* do_evt */ ,
+			    0 /* noblock */ );
+  if (rv < 0)
+    {
+      BIO_set_retry_write (b);
+      errno = EAGAIN;
+      return -1;
+    }
+
+  BIO_clear_retry_flags (b);
+
+  return rv;
+}
+
+long
+bio_tls_ctrl (BIO * b, int cmd, long larg, void *ptr)
+{
+  long ret = 1;
+
+  switch (cmd)
+    {
+    case BIO_C_SET_FD:
+      ASSERT (0);
+      break;
+    case BIO_C_GET_FD:
+      ASSERT (0);
+      break;
+    case BIO_CTRL_GET_CLOSE:
+      ret = BIO_get_shutdown (b);
+      break;
+    case BIO_CTRL_SET_CLOSE:
+      BIO_set_shutdown (b, (int) larg);
+      break;
+    case BIO_CTRL_DUP:
+    case BIO_CTRL_FLUSH:
+      ret = 1;
+      break;
+    case BIO_CTRL_PENDING:
+      ret = 0;
+      break;
+    default:
+      ret = 0;
+      break;
+    }
+  return ret;
+}
+
+BIO *
+BIO_new_tls (session_handle_t sh)
+{
+  static BIO_METHOD *tls_bio_method;
+  BIO *b;
+  if (!tls_bio_method)
+    {
+      tls_bio_method = BIO_meth_new (BIO_TYPE_SOCKET, "tls_bio");
+      BIO_meth_set_write (tls_bio_method, bio_tls_write);
+      BIO_meth_set_read (tls_bio_method, bio_tls_read);
+      BIO_meth_set_create (tls_bio_method, bio_tls_alloc);
+      BIO_meth_set_destroy (tls_bio_method, bio_tls_free);
+      BIO_meth_set_ctrl (tls_bio_method, bio_tls_ctrl);
+    }
+  b = BIO_new (tls_bio_method);
+  /* Initialize the BIO */
+  BIO_set_data (b, uword_to_pointer (sh, void *));
+  BIO_set_init (b, 1);
+  return b;
+}
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
diff --git a/src/plugins/tlsopenssl/tls_bio.h b/src/plugins/tlsopenssl/tls_bio.h
new file mode 100644
index 00000000000..b9f3c5384b9
--- /dev/null
+++ b/src/plugins/tlsopenssl/tls_bio.h
@@ -0,0 +1,31 @@
+/*
+ * Copyright (c) 2020 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.
+ */
+
+#ifndef SRC_PLUGINS_TLSOPENSSL_TLS_BIO_H_
+#define SRC_PLUGINS_TLSOPENSSL_TLS_BIO_H_
+
+#include <vnet/session/session_types.h>
+
+BIO *BIO_new_tls (session_handle_t sh);
+
+#endif /* SRC_PLUGINS_TLSOPENSSL_TLS_BIO_H_ */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
diff --git a/src/plugins/tlsopenssl/tls_openssl.c b/src/plugins/tlsopenssl/tls_openssl.c
index 669a503487f..5e49dbfe6c9 100644
--- a/src/plugins/tlsopenssl/tls_openssl.c
+++ b/src/plugins/tlsopenssl/tls_openssl.c
@@ -26,6 +26,7 @@
 #include <vnet/tls/tls.h>
 #include <ctype.h>
 #include <tlsopenssl/tls_openssl.h>
+#include <tlsopenssl/tls_bio.h>
 
 #define MAX_CRYPTO_LEN 64
 
@@ -110,39 +111,6 @@ openssl_lctx_get (u32 lctx_index)
 }
 
 static int
-openssl_read_from_bio_into_fifo (svm_fifo_t * f, BIO * bio, u32 enq_max)
-{
-  svm_fifo_chunk_t *c;
-  int read, rv;
-  u32 enq_now;
-
-  svm_fifo_fill_chunk_list (f);
-
-  enq_now = clib_min (svm_fifo_max_write_chunk (f), enq_max);
-  if (!enq_now)
-    return 0;
-
-  read = BIO_read (bio, svm_fifo_tail (f), enq_now);
-  if (read <= 0)
-    return 0;
-
-  c = svm_fifo_tail_chunk (f);
-  while ((c = c->next) && read < enq_max)
-    {
-      enq_now = clib_min (c->length, enq_max - read);
-      rv = BIO_read (bio, c->data, enq_now);
-      read += rv > 0 ? rv : 0;
-
-      if (rv < enq_now)
-	break;
-    }
-
-  svm_fifo_enqueue_nocopy (f, read);
-
-  return read;
-}
-
-static int
 openssl_read_from_ssl_into_fifo (svm_fifo_t * f, SSL * ssl)
 {
   u32 enq_now, enq_max;
@@ -180,34 +148,6 @@ openssl_read_from_ssl_into_fifo (svm_fifo_t * f, SSL * ssl)
 }
 
 static int
-openssl_write_from_fifo_into_bio (svm_fifo_t * f, BIO * bio, u32 len)
-{
-  svm_fifo_chunk_t *c;
-  int wrote, rv;
-  u32 deq_now;
-
-  deq_now = clib_min (svm_fifo_max_read_chunk (f), len);
-  wrote = BIO_write (bio, svm_fifo_head (f), deq_now);
-  if (wrote <= 0)
-    return 0;
-
-  c = svm_fifo_head_chunk (f);
-  while ((c = c->next) && wrote < len)
-    {
-      deq_now = clib_min (c->length, len - wrote);
-      rv = BIO_write (bio, c->data, deq_now);
-      wrote += rv > 0 ? rv : 0;
-
-      if (rv < deq_now)
-	break;
-    }
-
-  svm_fifo_dequeue_drop (f, wrote);
-
-  return wrote;
-}
-
-static int
 openssl_write_from_fifo_into_ssl (svm_fifo_t * f, SSL * ssl, u32 len)
 {
   svm_fifo_chunk_t *c;
@@ -235,40 +175,6 @@ openssl_write_from_fifo_into_ssl (svm_fifo_t * f, SSL * ssl, u32 len)
   return wrote;
 }
 
-static int
-openssl_try_handshake_read (openssl_ctx_t * oc, session_t * tls_session)
-{
-  svm_fifo_t *f;
-  u32 deq_max;
-
-  f = tls_session->rx_fifo;
-  deq_max = svm_fifo_max_dequeue_cons (f);
-  if (!deq_max)
-    return 0;
-
-  return openssl_write_from_fifo_into_bio (f, oc->wbio, deq_max);
-}
-
-static int
-openssl_try_handshake_write (openssl_ctx_t * oc, session_t * tls_session)
-{
-  u32 read, enq_max;
-
-  if (BIO_ctrl_pending (oc->rbio) <= 0)
-    return 0;
-
-  enq_max = svm_fifo_max_enqueue_prod (tls_session->tx_fifo);
-  if (!enq_max)
-    return 0;
-
-  read = openssl_read_from_bio_into_fifo (tls_session->tx_fifo, oc->rbio,
-					  enq_max);
-  if (read)
-    tls_add_vpp_q_tx_evt (tls_session);
-
-  return read;
-}
-
 #ifdef HAVE_OPENSSL_ASYNC
 static int
 openssl_check_async_status (tls_ctx_t * ctx, openssl_resume_handler * handler,
@@ -334,7 +240,7 @@ openssl_ctx_handshake_rx (tls_ctx_t * ctx, session_t * tls_session)
 	{
 	  ctx->resume = 0;
 	}
-      else if (!openssl_try_handshake_read (oc, tls_session))
+      else if (!svm_fifo_max_dequeue_cons (tls_session->rx_fifo))
 	break;
 
       rv = SSL_do_handshake (oc->ssl);
@@ -357,9 +263,7 @@ openssl_ctx_handshake_rx (tls_ctx_t * ctx, session_t * tls_session)
 	  return -1;
 	}
 
-      openssl_try_handshake_write (oc, tls_session);
-
-      if (err != SSL_ERROR_WANT_WRITE)
+      if (err != SSL_ERROR_WANT_WRITE && err != SSL_ERROR_WANT_READ)
 	break;
     }
   TLS_DBG (2, "tls state for %u is %s", oc->openssl_ctx_index,
@@ -418,25 +322,26 @@ openssl_ctx_write (tls_ctx_t * ctx, session_t * app_session,
 		   transport_send_params_t * sp)
 {
   openssl_ctx_t *oc = (openssl_ctx_t *) ctx;
-  int wrote = 0, read, max_buf = 4 * TLS_CHUNK_SIZE, max_space, n_pending;
-  u32 deq_max, to_write, enq_max;
-  session_t *tls_session;
+  u32 deq_max, space, enq_buf;
+  session_t *ts;
+  int wrote = 0;
   svm_fifo_t *f;
 
+  ts = session_get_from_handle (ctx->tls_session_handle);
+  space = svm_fifo_max_enqueue_prod (ts->tx_fifo);
+  /* Leave a bit of extra space for tls ctrl data, if any needed */
+  space = clib_max ((int) space - TLSO_CTRL_BYTES, 0);
+
   f = app_session->tx_fifo;
 
   deq_max = svm_fifo_max_dequeue_cons (f);
+  deq_max = clib_min (deq_max, space);
   if (!deq_max)
     goto check_tls_fifo;
 
   deq_max = clib_min (deq_max, sp->max_burst_size);
 
-  /* Figure out how much data to write */
-  max_space = max_buf - BIO_ctrl_pending (oc->rbio);
-  max_space = (max_space < 0) ? 0 : max_space;
-  to_write = clib_min (deq_max, (u32) max_space);
-
-  wrote = openssl_write_from_fifo_into_ssl (f, oc->ssl, to_write);
+  wrote = openssl_write_from_fifo_into_ssl (f, oc->ssl, deq_max);
   if (!wrote)
     goto check_tls_fifo;
 
@@ -445,31 +350,11 @@ openssl_ctx_write (tls_ctx_t * ctx, session_t * app_session,
 
 check_tls_fifo:
 
-  if ((n_pending = BIO_ctrl_pending (oc->rbio)) <= 0)
-    return wrote;
-
-  tls_session = session_get_from_handle (ctx->tls_session_handle);
-
-  enq_max = svm_fifo_max_enqueue_prod (tls_session->tx_fifo);
-  if (!enq_max)
-    goto maybe_reschedule;
-
-  read = openssl_read_from_bio_into_fifo (tls_session->tx_fifo, oc->rbio,
-					  enq_max);
-  if (!read)
-    goto maybe_reschedule;
-
-  tls_add_vpp_q_tx_evt (tls_session);
-
-  if (PREDICT_FALSE (ctx->app_closed && !BIO_ctrl_pending (oc->rbio)))
-    openssl_confirm_app_close (ctx);
-
-maybe_reschedule:
-
-  if (!svm_fifo_max_enqueue_prod (tls_session->tx_fifo))
+  /* Deschedule and wait for deq notification if fifo is almost full */
+  enq_buf = clib_min (svm_fifo_size (ts->tx_fifo) / 2, TLSO_MIN_ENQ_SPACE);
+  if (space < wrote + enq_buf)
     {
-      svm_fifo_add_want_deq_ntf (tls_session->tx_fifo,
-				 SVM_FIFO_WANT_DEQ_NOTIF);
+      svm_fifo_add_want_deq_ntf (ts->tx_fifo, SVM_FIFO_WANT_DEQ_NOTIF);
       transport_connection_deschedule (&ctx->connection);
       sp->flags |= TRANSPORT_SND_F_DESCHED;
     }
@@ -483,57 +368,26 @@ maybe_reschedule:
 static inline int
 openssl_ctx_read (tls_ctx_t * ctx, session_t * tls_session)
 {
-  int read, wrote = 0, max_space, max_buf = 4 * TLS_CHUNK_SIZE;
   openssl_ctx_t *oc = (openssl_ctx_t *) ctx;
-  u32 deq_max, to_write;
   session_t *app_session;
+  int read, wrote = 0;
   svm_fifo_t *f;
 
   if (PREDICT_FALSE (SSL_in_init (oc->ssl)))
     {
       if (openssl_ctx_handshake_rx (ctx, tls_session) < 0)
 	return 0;
-      else
-	goto check_app_fifo;
-    }
-
-  f = tls_session->rx_fifo;
-
-  deq_max = svm_fifo_max_dequeue_cons (f);
-  max_space = max_buf - BIO_ctrl_pending (oc->wbio);
-  max_space = max_space < 0 ? 0 : max_space;
-  to_write = clib_min (deq_max, max_space);
-  if (!to_write)
-    goto check_app_fifo;
-
-  wrote = openssl_write_from_fifo_into_bio (f, oc->wbio, to_write);
-  if (!wrote)
-    {
-      tls_add_vpp_q_builtin_rx_evt (tls_session);
-      goto check_app_fifo;
     }
 
-  if (svm_fifo_max_dequeue_cons (f))
-    tls_add_vpp_q_builtin_rx_evt (tls_session);
-
-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->rx_fifo;
 
   read = openssl_read_from_ssl_into_fifo (f, oc->ssl);
-  if (!read)
-    {
-      tls_add_vpp_q_builtin_rx_evt (tls_session);
-      return wrote;
-    }
 
   /* If handshake just completed, session may still be in accepting state */
-  if (app_session->session_state >= SESSION_STATE_READY)
+  if (read && app_session->session_state >= SESSION_STATE_READY)
     tls_notify_app_enqueue (ctx, app_session);
+
   if (SSL_pending (oc->ssl) > 0)
     tls_add_vpp_q_builtin_rx_evt (tls_session);
 
@@ -546,7 +400,6 @@ openssl_ctx_init_client (tls_ctx_t * ctx)
   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;
-  session_t *tls_session;
   const SSL_METHOD *method;
   int rv, err;
 
@@ -587,11 +440,8 @@ openssl_ctx_init_client (tls_ctx_t * ctx)
       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);
+  oc->rbio = BIO_new_tls (ctx->tls_session_handle);
+  oc->wbio = BIO_new_tls (ctx->tls_session_handle);
 
   SSL_set_bio (oc->ssl, oc->wbio, oc->rbio);
   SSL_set_connect_state (oc->ssl);
@@ -609,16 +459,14 @@ openssl_ctx_init_client (tls_ctx_t * ctx)
   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);
-
 #ifdef HAVE_OPENSSL_ASYNC
+  session_t *tls_session = session_get_from_handle (ctx->tls_session_handle);
   vpp_tls_async_init_event (ctx, openssl_ctx_handshake_rx, tls_session);
 #endif
   while (1)
     {
       rv = SSL_do_handshake (oc->ssl);
       err = SSL_get_error (oc->ssl, rv);
-      openssl_try_handshake_write (oc, tls_session);
 #ifdef HAVE_OPENSSL_ASYNC
       if (err == SSL_ERROR_WANT_ASYNC)
 	{
@@ -751,7 +599,6 @@ openssl_ctx_init_server (tls_ctx_t * ctx)
   openssl_ctx_t *oc = (openssl_ctx_t *) ctx;
   u32 olc_index = ctx->tls_ssl_ctx;
   openssl_listen_ctx_t *olc;
-  session_t *tls_session;
   int rv, err;
 
   /* Start a new connection */
@@ -764,11 +611,8 @@ openssl_ctx_init_server (tls_ctx_t * ctx)
       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);
+  oc->rbio = BIO_new_tls (ctx->tls_session_handle);
+  oc->wbio = BIO_new_tls (ctx->tls_session_handle);
 
   SSL_set_bio (oc->ssl, oc->wbio, oc->rbio);
   SSL_set_accept_state (oc->ssl);
@@ -776,15 +620,14 @@ openssl_ctx_init_server (tls_ctx_t * ctx)
   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);
 #ifdef HAVE_OPENSSL_ASYNC
+  session_t *tls_session = session_get_from_handle (ctx->tls_session_handle);
   vpp_tls_async_init_event (ctx, openssl_ctx_handshake_rx, tls_session);
 #endif
   while (1)
     {
       rv = SSL_do_handshake (oc->ssl);
       err = SSL_get_error (oc->ssl, rv);
-      openssl_try_handshake_write (oc, tls_session);
 #ifdef HAVE_OPENSSL_ASYNC
       if (err == SSL_ERROR_WANT_ASYNC)
 	{
diff --git a/src/plugins/tlsopenssl/tls_openssl.h b/src/plugins/tlsopenssl/tls_openssl.h
index 5744dcadb3a..16b256d0ceb 100644
--- a/src/plugins/tlsopenssl/tls_openssl.h
+++ b/src/plugins/tlsopenssl/tls_openssl.h
@@ -21,6 +21,9 @@
 #include <vpp/app/version.h>
 #include <vnet/tls/tls.h>
 
+#define TLSO_CTRL_BYTES 1000
+#define TLSO_MIN_ENQ_SPACE (1 << 16)
+
 typedef struct tls_ctx_openssl_
 {
   tls_ctx_t ctx;			/**< First */