From 8b1af2f89c9a3e26e748e3c856c9411425b988e1 Mon Sep 17 00:00:00 2001
From: Hanno Becker <hanno.becker@arm.com>
Date: Wed, 3 Jul 2019 17:02:43 +0100
Subject: [PATCH] Add IO wrappers to ssl_client2 as interm's between NET and
 SSL layer

---
 programs/ssl/ssl_client2.c | 80 ++++++++++++++++++++++++++++++++++----
 1 file changed, 72 insertions(+), 8 deletions(-)

diff --git a/programs/ssl/ssl_client2.c b/programs/ssl/ssl_client2.c
index 4221159d4..6ff55e656 100644
--- a/programs/ssl/ssl_client2.c
+++ b/programs/ssl/ssl_client2.c
@@ -617,7 +617,8 @@ exit:
  * Test recv/send functions that make sure each try returns
  * WANT_READ/WANT_WRITE at least once before sucesseding
  */
-static int my_recv( void *ctx, unsigned char *buf, size_t len )
+
+static int delayed_recv( void *ctx, unsigned char *buf, size_t len )
 {
     static int first_try = 1;
     int ret;
@@ -634,7 +635,7 @@ static int my_recv( void *ctx, unsigned char *buf, size_t len )
     return( ret );
 }
 
-static int my_send( void *ctx, const unsigned char *buf, size_t len )
+static int delayed_send( void *ctx, const unsigned char *buf, size_t len )
 {
     static int first_try = 1;
     int ret;
@@ -651,6 +652,70 @@ static int my_send( void *ctx, const unsigned char *buf, size_t len )
     return( ret );
 }
 
+typedef struct
+{
+    mbedtls_ssl_context *ssl;
+    mbedtls_net_context *net;
+} io_ctx_t;
+
+static int recv_cb( void *ctx, unsigned char *buf, size_t len )
+{
+    io_ctx_t *io_ctx = (io_ctx_t*) ctx;
+    size_t recv_len;
+    int ret;
+
+    if( opt.nbio == 2 )
+        ret = delayed_recv( io_ctx->net, buf, len );
+    else
+        ret = mbedtls_net_recv( io_ctx->net, buf, len );
+    if( ret < 0 )
+        return( ret );
+    recv_len = (size_t) ret;
+
+    if( opt.transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
+    {
+        /* Here's the place to do any datagram/record checking
+         * in between receiving the packet from the underlying
+         * transport and passing it on to the TLS stack. */
+        mbedtls_printf( "[RECV] Datagram of size %u\n", (unsigned) recv_len );
+    }
+
+    return( (int) recv_len );
+}
+
+static int recv_timeout_cb( void *ctx, unsigned char *buf, size_t len,
+                            uint32_t timeout )
+{
+    io_ctx_t *io_ctx = (io_ctx_t*) ctx;
+    int ret;
+    size_t recv_len;
+
+    ret = mbedtls_net_recv_timeout( io_ctx->net, buf, len, timeout );
+    if( ret < 0 )
+        return( ret );
+    recv_len = (size_t) ret;
+
+    if( opt.transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
+    {
+        /* Here's the place to do any datagram/record checking
+         * in between receiving the packet from the underlying
+         * transport and passing it on to the TLS stack. */
+        mbedtls_printf( "[RECV] Datagram of size %u\n", (unsigned) recv_len );
+    }
+
+    return( (int) recv_len );
+}
+
+static int send_cb( void *ctx, unsigned char const *buf, size_t len )
+{
+    io_ctx_t *io_ctx = (io_ctx_t*) ctx;
+
+    if( opt.nbio == 2 )
+        return( delayed_send( io_ctx->net, buf, len ) );
+
+    return( mbedtls_net_send( io_ctx->net, buf, len ) );
+}
+
 #if defined(MBEDTLS_X509_CRT_PARSE_C)
 static unsigned char peer_crt_info[1024];
 
@@ -874,6 +939,7 @@ int main( int argc, char *argv[] )
 {
     int ret = 0, len, tail_len, i, written, frags, retry_left;
     mbedtls_net_context server_fd;
+    io_ctx_t io_ctx;
 
     unsigned char buf[MAX_REQUEST_SIZE + 1];
 
@@ -2162,12 +2228,10 @@ int main( int argc, char *argv[] )
         mbedtls_ssl_set_verify( &ssl, my_verify, NULL );
 #endif /* MBEDTLS_X509_CRT_PARSE_C */
 
-    if( opt.nbio == 2 )
-        mbedtls_ssl_set_bio( &ssl, &server_fd, my_send, my_recv, NULL );
-    else
-        mbedtls_ssl_set_bio( &ssl, &server_fd,
-                             mbedtls_net_send, mbedtls_net_recv,
-                             opt.nbio == 0 ? mbedtls_net_recv_timeout : NULL );
+    io_ctx.ssl = &ssl;
+    io_ctx.net = &server_fd;
+    mbedtls_ssl_set_bio( &ssl, &io_ctx, send_cb, recv_cb,
+                         opt.nbio == 0 ? recv_timeout_cb : NULL );
 
 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
     if( opt.transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )