diff --git a/deps/mariadb-client-library/UPGRADE_NOTES.md b/deps/mariadb-client-library/UPGRADE_NOTES.md
new file mode 100644
index 000000000..32e1a7f0c
--- /dev/null
+++ b/deps/mariadb-client-library/UPGRADE_NOTES.md
@@ -0,0 +1,4 @@
+Please note that upgrading `mariadb-connector-c` can require some changes
+in `include/MySQL_Data_Stream.h` where we define `P_MARIADB_TLS` as a copy
+of `MARIADB_TLS` . If `MARIADB_TLS` is changed, `P_MARIADB_TLS` must be
+updated too.
diff --git a/deps/mariadb-client-library/mariadb-connector-c-2.3.1-src.tar.gz b/deps/mariadb-client-library/mariadb-connector-c-2.3.1-src.tar.gz
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diff --git a/deps/mariadb-client-library/mariadb-connector-c-3.0.2-src.tar.gz b/deps/mariadb-client-library/mariadb-connector-c-3.0.2-src.tar.gz
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diff --git a/deps/mariadb-client-library/mariadb-connector-c-3.0.9-src.tar.gz b/deps/mariadb-client-library/mariadb-connector-c-3.0.9-src.tar.gz
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diff --git a/deps/mariadb-client-library/mariadb-connector-c-3.1.4-src.tar.gz b/deps/mariadb-client-library/mariadb-connector-c-3.1.4-src.tar.gz
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diff --git a/include/MySQL_Data_Stream.h b/include/MySQL_Data_Stream.h
index 0c71582b2..19627975d 100644
--- a/include/MySQL_Data_Stream.h
+++ b/include/MySQL_Data_Stream.h
@@ -6,6 +6,21 @@
 
 #include "MySQL_Protocol.h"
 
+#ifndef uchar
+typedef unsigned char uchar;
+#endif
+
+#include "ma_pvio.h"
+// here we define P_MARIADB_TLS as a copy of MARIADB_TLS
+// copied from ma_tls.h
+// note that ma_pvio.h defines it as void
+typedef struct P_st_ma_pvio_tls {
+  void *data;
+  MARIADB_PVIO *pvio;
+  void *ssl;
+} P_MARIADB_TLS;
+
+
 #define QUEUE_T_DEFAULT_SIZE	32768
 #define MY_SSL_BUFFER	8192
 
@@ -192,6 +207,26 @@ class MySQL_Data_Stream
 		myconn=mc;
 		myconn->statuses.myconnpoll_get++;
 		mc->myds=this;
+		// we handle encryption for backend
+		//
+		// we have a similar code in MySQL_Connection
+		// in case of ASYNC_CONNECT_SUCCESSFUL
+		encrypted = false;
+		if (sess != NULL && sess->session_fast_forward == true) {
+			if (myconn->mysql && myconn->ret_mysql) {
+				if (myconn->mysql->options.use_ssl == 1) {
+					encrypted = true;
+					if (ssl == NULL) {
+						// check the definition of P_MARIADB_TLS
+						P_MARIADB_TLS * matls = (P_MARIADB_TLS *)myconn->mysql->net.pvio->ctls;
+						ssl = (SSL *)matls->ssl;
+						rbio_ssl = BIO_new(BIO_s_mem());
+						wbio_ssl = BIO_new(BIO_s_mem());
+						SSL_set_bio(ssl, rbio_ssl, wbio_ssl);
+					}
+				}
+			}
+		}
 	}
 
 	// safe way to detach a MySQL Connection
diff --git a/lib/mysql_connection.cpp b/lib/mysql_connection.cpp
index a02e274be..c51df2fdd 100644
--- a/lib/mysql_connection.cpp
+++ b/lib/mysql_connection.cpp
@@ -22,6 +22,7 @@ void ma_free_root(MA_MEM_ROOT *root, myf MyFLAGS);
 void *ma_alloc_root(MA_MEM_ROOT *mem_root, size_t Size);
 #define MAX(a,b) (((a) > (b)) ? (a) : (b))
 
+
 void * ma_alloc_root(MA_MEM_ROOT *mem_root, size_t Size)
 {
   size_t get_size;
@@ -1113,6 +1114,26 @@ handler_again:
 			}
     	break;
 		case ASYNC_CONNECT_SUCCESSFUL:
+			if (mysql && ret_mysql) {
+				// we handle encryption for backend
+				//
+				// we have a similar code in MySQL_Data_Stream::attach_connection()
+				if (mysql->options.use_ssl == 1)
+					if (myds)
+						if (myds->sess != NULL)
+							if (myds->sess->session_fast_forward == true) {
+								myds->encrypted = true;
+								assert(myds->ssl==NULL);
+								if (myds->ssl == NULL) {
+									// check the definition of P_MARIADB_TLS
+									P_MARIADB_TLS * matls = (P_MARIADB_TLS *)mysql->net.pvio->ctls;
+									myds->ssl = (SSL *)matls->ssl;
+									myds->rbio_ssl = BIO_new(BIO_s_mem());
+									myds->wbio_ssl = BIO_new(BIO_s_mem());
+									SSL_set_bio(myds->ssl, myds->rbio_ssl, myds->wbio_ssl);
+								}
+							}
+			}
 			__sync_fetch_and_add(&MyHGM->status.server_connections_connected,1);
 			__sync_fetch_and_add(&parent->connect_OK,1);
 			options.client_flag = mysql->client_flag;