Change non-blocking read/write in TCP mock socket

Previously mocked non-blocking read/write was returning 0 when buffer was empty/full. That was causing ERR_SSL_CONN_EOF error in tests which was using these mocked callbacks. Beside that non-blocking read/write was returning ERR_SSL_WANT_READ/_WRITE depending on block pattern set by test design. Such behavior forced to redesign of these functions so that they could be used in other tests

tests/suites/test_suite_ssl.data

@@ -35,34 +35,16 @@ Test mock socket sanity
 ssl_mock_sanity:
 
 Test mock blocking TCP connection
-ssl_mock_tcp:1:0:0
+ssl_mock_tcp:1
 
-Test mock non-blocking TCP connection: would not block
+Test mock non-blocking TCP connection
-ssl_mock_tcp:0:0:0
+ssl_mock_tcp:0
-
-Test mock non-blocking TCP connection: client would block
-ssl_mock_tcp:0:0xB509:0
-
-Test mock non-blocking TCP connection: server would block
-ssl_mock_tcp:0:0x0FB1:0
-
-Test mock non-blocking TCP connection: both peers would block
-ssl_mock_tcp:0:0x1111:0xEEEE
 
 Test mock blocking TCP connection (interleaving)
-ssl_mock_tcp_interleaving:1:0:0
+ssl_mock_tcp_interleaving:1
 
-Test mock non-blocking TCP connection: would not block (interleaving)
+Test mock non-blocking TCP connection (interleaving)
-ssl_mock_tcp_interleaving:0:0:0
+ssl_mock_tcp_interleaving:0
-
-Test mock non-blocking TCP connection: client would block (interleaving)
-ssl_mock_tcp_interleaving:0:0xB509:0
-
-Test mock non-blocking TCP connection: server would block (interleaving)
-ssl_mock_tcp_interleaving:0:0x0FB1:0
-
-Test mock non-blocking TCP connection: both peers would block (interleaving)
-ssl_mock_tcp_interleaving:0:0x1111:0xEEEE
 
 SSL DTLS replay: initial state, seqnum 0
 ssl_dtls_replay:"":"000000000000":0

tests/suites/test_suite_ssl.function

@@ -159,7 +159,6 @@ int mbedtls_test_buffer_get( mbedtls_test_buffer *buf,
 typedef struct mbedtls_mock_socket
 {
     int status;
-    uint32_t blocking_pattern;
     mbedtls_test_buffer *input;
     mbedtls_test_buffer *output;
     struct mbedtls_mock_socket *peer;
@@ -268,26 +267,6 @@ exit:
     return ret;
 }
 
-/*
- * Set the blocking pattern for the socket.
- *
- * For every bit of \p blocking_pattern set to one the socket will simulate a
- * "would block" event. The bits are processed starting with the least
- * significant bit and every call to a non-blocking I/O function consumes one.
- *
- * The behaviour of blocking I/O functions remains unchanged.
- */
-int mbedtls_mock_socket_set_block( mbedtls_mock_socket* socket,
-                                   uint32_t blocking_pattern )
-{
-    if( socket == NULL )
-        return -1;
-
-    socket->blocking_pattern = blocking_pattern;
-
-    return 0;
-}
-
 /*
  * Callbacks for simulating blocking I/O over connection-oriented transport.
  */
@@ -323,14 +302,11 @@ int mbedtls_mock_tcp_send_nb( void *ctx, const unsigned char *buf, size_t len )
     if( socket == NULL || socket->status != MBEDTLS_MOCK_SOCKET_CONNECTED )
         return -1;
 
-    if( socket->blocking_pattern & 1 )
+    if( socket->output->capacity == socket->output->content_length )
     {
-        socket->blocking_pattern >>= 1;
         return MBEDTLS_ERR_SSL_WANT_WRITE;
     }
 
-    socket->blocking_pattern >>= 1;
-
     return mbedtls_test_buffer_put( socket->output, buf, len );
 }
 
@@ -341,14 +317,11 @@ int mbedtls_mock_tcp_recv_nb( void *ctx, unsigned char *buf, size_t len )
     if( socket == NULL || socket->status != MBEDTLS_MOCK_SOCKET_CONNECTED )
         return -1;
 
-    if( socket->blocking_pattern & 1 )
+    if( socket->input->content_length == 0)
     {
-        socket->blocking_pattern >>= 1;
         return MBEDTLS_ERR_SSL_WANT_READ;
     }
 
-    socket->blocking_pattern >>= 1;
-
     return mbedtls_test_buffer_get( socket->input, buf, len );
 }
 
@@ -928,9 +901,10 @@ exit:
  */
 
 /* BEGIN_CASE */
-void ssl_mock_tcp( int blocking, int client_pattern, int server_pattern )
+void ssl_mock_tcp( int blocking )
 {
     enum { MSGLEN = 105 };
+    enum { BUFLEN = MSGLEN / 5 };
     unsigned char message[MSGLEN];
     unsigned char received[MSGLEN];
     mbedtls_mock_socket client;
@@ -939,8 +913,6 @@ void ssl_mock_tcp( int blocking, int client_pattern, int server_pattern )
     int send_ret, recv_ret;
     mbedtls_ssl_send_t *send;
     mbedtls_ssl_recv_t *recv;
-    uint32_t client_block = client_pattern;
-    uint32_t server_block = server_pattern;
     unsigned i;
 
     if( blocking == 0 )
@@ -965,10 +937,7 @@ void ssl_mock_tcp( int blocking, int client_pattern, int server_pattern )
     }
 
     /* Make sure that sending a message takes a few  iterations. */
-    TEST_ASSERT( 0 == mbedtls_mock_socket_connect( &client, &server,
+    TEST_ASSERT( 0 == mbedtls_mock_socket_connect( &client, &server, BUFLEN ) );
-                                                   MSGLEN / 5 ) );
-    TEST_ASSERT( 0 == mbedtls_mock_socket_set_block( &client, client_block ) );
-    TEST_ASSERT( 0 == mbedtls_mock_socket_set_block( &server, server_block ) );
 
     /* Send the message to the server */
     send_ret = recv_ret = 1;
@@ -977,28 +946,56 @@ void ssl_mock_tcp( int blocking, int client_pattern, int server_pattern )
     {
         send_ret = send( &client, message + written, MSGLEN - written );
 
-        if( ( blocking == 0 ) && ( client_block & 1 ) )
+        TEST_ASSERT( send_ret >= 0 );
+        TEST_ASSERT( send_ret <= BUFLEN );
+        written += send_ret;
+
+        /* If the buffer is full we can test blocking and non-blocking send */
+        if ( send_ret == BUFLEN )
         {
-            TEST_ASSERT( send_ret == MBEDTLS_ERR_SSL_WANT_WRITE );
+            int blocking_ret = send( &client, message , 1 );
+            if ( blocking )
+            {
+                TEST_ASSERT( blocking_ret == 0 );
             }
             else
             {
-            TEST_ASSERT( send_ret >= 0 );
+                TEST_ASSERT( blocking_ret == MBEDTLS_ERR_SSL_WANT_WRITE );
-            written += send_ret;
+            }
         }
-        client_block >>= 1;
 
         recv_ret = recv( &server, received + read, MSGLEN - read );
-        if( ( blocking == 0 ) && ( server_block & 1 ) )
+
+        /* The result depends on whether any data was sent */
+        if ( send_ret > 0 )
         {
-            TEST_ASSERT( recv_ret == MBEDTLS_ERR_SSL_WANT_READ );
+            TEST_ASSERT( recv_ret > 0 );
+            TEST_ASSERT( recv_ret <= BUFLEN );
+            read += recv_ret;
+        }
+        else if( blocking )
+        {
+            TEST_ASSERT( recv_ret == 0 );
         }
         else
         {
-            TEST_ASSERT( recv_ret >= 0 );
+            TEST_ASSERT( recv_ret == MBEDTLS_ERR_SSL_WANT_READ );
-            read += recv_ret;
+            recv_ret = 0;
+        }
+
+        /* If the buffer is empty we can test blocking and non-blocking read */
+        if ( recv_ret == BUFLEN )
+        {
+            int blocking_ret = recv( &server, received, 1 );
+            if ( blocking )
+            {
+                TEST_ASSERT( blocking_ret == 0 );
+            }
+            else
+            {
+                TEST_ASSERT( blocking_ret == MBEDTLS_ERR_SSL_WANT_READ );
+            }
         }
-        server_block >>= 1;
     }
     TEST_ASSERT( memcmp( message, received, MSGLEN ) == 0 );
 
@@ -1016,11 +1013,11 @@ exit:
  */
 
 /* BEGIN_CASE */
-void ssl_mock_tcp_interleaving( int blocking,
+void ssl_mock_tcp_interleaving( int blocking )
-                                int client_pattern, int server_pattern )
 {
     enum { ROUNDS = 2 };
     enum { MSGLEN = 105 };
+    enum { BUFLEN = MSGLEN / 5 };
     unsigned char message[ROUNDS][MSGLEN];
     unsigned char received[ROUNDS][MSGLEN];
     mbedtls_mock_socket client;
@@ -1032,8 +1029,6 @@ void ssl_mock_tcp_interleaving( int blocking,
     unsigned i, j, progress;
     mbedtls_ssl_send_t *send;
     mbedtls_ssl_recv_t *recv;
-    uint32_t client_block = client_pattern;
-    uint32_t server_block = server_pattern;
 
     if( blocking == 0 )
     {
@@ -1060,10 +1055,7 @@ void ssl_mock_tcp_interleaving( int blocking,
     }
 
     /* Make sure that sending a message takes a few  iterations. */
-    TEST_ASSERT( 0 == mbedtls_mock_socket_connect( &client, &server,
+    TEST_ASSERT( 0 == mbedtls_mock_socket_connect( &client, &server, BUFLEN ) );
-                                                   MSGLEN / 5 ) );
-    TEST_ASSERT( 0 == mbedtls_mock_socket_set_block( &client, client_block ) );
-    TEST_ASSERT( 0 == mbedtls_mock_socket_set_block( &server, server_block ) );
 
     /* Send the message from both sides, interleaving. */
     progress = 1;
@@ -1076,72 +1068,80 @@ void ssl_mock_tcp_interleaving( int blocking,
      * of at least one byte on either side. */
     while( progress != 0 )
     {
-        send_ret[0] = send( &client, message[0] + written[0],
+        mbedtls_mock_socket *socket;
-                                               MSGLEN - written[0] );
-        if( ( blocking == 0 ) && ( client_block & 1 ) )
-        {
-            TEST_ASSERT( send_ret[0] == MBEDTLS_ERR_SSL_WANT_WRITE );
-        }
-        else
-        {
-            TEST_ASSERT( send_ret[0] >= 0 );
-            written[0] += send_ret[0];
-        }
-        client_block >>= 1;
 
-        send_ret[1] = send( &server, message[1] + written[1],
+        for( i = 0; i < ROUNDS; i++ )
-                                               MSGLEN - written[1] );
-        if( ( blocking == 0 ) && ( server_block & 1 ) )
         {
-            TEST_ASSERT( send_ret[1] == MBEDTLS_ERR_SSL_WANT_WRITE );
+            /* First sending is from the client */
-        }
+            socket = ( i % 2 == 0 ) ? ( &client ) : ( &server );
-        else
-        {
-            TEST_ASSERT( send_ret[1] >= 0 );
-            written[1] += send_ret[1];
-        }
-        server_block >>= 1;
 
-        recv_ret[0] = recv( &server, received[0] + read[0],
+            send_ret[i] = send( socket, message[i] + written[i],
-                                               MSGLEN - read[0] );
+                                               MSGLEN - written[i] );
-        if( ( blocking == 0 ) && ( server_block & 1 ) )
+            TEST_ASSERT( send_ret[i] >= 0 );
-        {
+            TEST_ASSERT( send_ret[i] <= BUFLEN );
-            TEST_ASSERT( recv_ret[0] == MBEDTLS_ERR_SSL_WANT_READ );
+            written[i] += send_ret[i];
-        }
-        else
-        {
-            TEST_ASSERT( recv_ret[0] >= 0 );
-            read[0] += recv_ret[0];
-        }
-        server_block >>= 1;
 
-        recv_ret[1] = recv( &client, received[1] + read[1],
+            /* If the buffer is full we can test blocking and non-blocking
-                                               MSGLEN - read[1] );
+             * send */
-        if( ( blocking == 0 ) && ( client_block & 1 ) )
+            if ( send_ret[i] == BUFLEN )
             {
-            TEST_ASSERT( recv_ret[1] == MBEDTLS_ERR_SSL_WANT_READ );
+                int blocking_ret = send( socket, message[i] , 1 );
+                if ( blocking )
+                {
+                    TEST_ASSERT( blocking_ret == 0 );
                 }
                 else
                 {
-            TEST_ASSERT( recv_ret[1] >= 0 );
+                    TEST_ASSERT( blocking_ret == MBEDTLS_ERR_SSL_WANT_WRITE );
-            read[1] += recv_ret[1];
+                }
+            }
+        }
+
+        for( i = 0; i < ROUNDS; i++ )
+        {
+            /* First receiving is from the server */
+            socket = ( i % 2 == 0 ) ? ( &server ) : ( &client );
+
+            recv_ret[i] = recv( socket, received[i] + read[i],
+                                               MSGLEN - read[i] );
+
+            /* The result depends on whether any data was sent */
+            if ( send_ret[i] > 0 )
+            {
+                TEST_ASSERT( recv_ret[i] > 0 );
+                TEST_ASSERT( recv_ret[i] <= BUFLEN );
+                read[i] += recv_ret[i];
+            }
+            else if( blocking )
+            {
+                TEST_ASSERT( recv_ret[i] == 0 );
+            }
+            else
+            {
+                TEST_ASSERT( recv_ret[i] == MBEDTLS_ERR_SSL_WANT_READ );
+                recv_ret[i] = 0;
+            }
+
+            /* If the buffer is empty we can test blocking and non-blocking
+             * read */
+            if ( recv_ret[i] == BUFLEN )
+            {
+                int blocking_ret = recv( socket, received[i], 1 );
+                if ( blocking )
+                {
+                    TEST_ASSERT( blocking_ret == 0 );
+                }
+                else
+                {
+                    TEST_ASSERT( blocking_ret == MBEDTLS_ERR_SSL_WANT_READ );
+                }
+            }
         }
-        client_block >>= 1;
 
         progress = 0;
         for( i = 0; i < ROUNDS; i++ )
         {
-            if( ( send_ret[i] > 0 ) ||
+            progress += send_ret[i] + recv_ret[i];
-                    ( send_ret[i] == MBEDTLS_ERR_SSL_WANT_WRITE ) )
-            {
-                progress++;
-            }
-
-            if( ( recv_ret[i] > 0 ) ||
-                    ( recv_ret[i] == MBEDTLS_ERR_SSL_WANT_READ ) )
-            {
-                progress++;
-            }
         }
     }