sound redirection: handle fragmented packets

sesman/chansrv/Makefile.am

@@ -9,7 +9,8 @@ EXTRA_DIST = \
   rail.h \
   sound.h \
   xcommon.h \
-  mlog.h
+  mlog.h \
+  chansrv_common.h
 
 EXTRA_DEFINES =
 EXTRA_INCLUDES =
@@ -48,7 +49,8 @@ xrdp_chansrv_SOURCES = \
   drdynvc.c \
   chansrv_fuse.c \
   irp.c \
-  fifo.c
+  fifo.c \
+  chansrv_common.c
 
 xrdp_chansrv_LDFLAGS = \
   $(EXTRA_FLAGS)

sesman/chansrv/chansrv_common.c

@@ -0,0 +1,73 @@
+/**
+ * xrdp: A Remote Desktop Protocol server.
+ *
+ * Copyright (C) Laxmikant Rashinkar 2009-2014
+ *
+ * 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 "chansrv_common.h"
+
+/**
+ * Assemble fragmented incoming packets into one stream
+ *
+ * @param  src           stream that contains partial data
+ * @param  dest          stream that contains entire data
+ * @param  chan_flags    fragmentation flags
+ * @param  length        bytes in this packet
+ * @param  total_length  total length of assembled packet
+ *
+ * @return 1 when all data has been assembled, 0 otherwise
+ *
+ * NOTE: it is the responsibility of the caller to free dest stream
+ ****************************************************************************/
+int
+read_entire_packet(struct stream *src, struct stream **dest, int chan_flags,
+                   int length, int total_length)
+{
+    struct stream *ls;
+
+    if ((chan_flags & 3) == 3)
+    {
+        /* packet not fragmented */
+        xstream_new(ls, total_length);
+        xstream_copyin(ls, src->p, length);
+        ls->p = ls->data;
+        *dest = ls;
+        return 1;
+    }
+
+    /* is this the first fragmented packet? */
+    if (chan_flags & 1)
+    {
+        xstream_new(ls, total_length);
+        *dest = ls;
+    }
+    else
+    {
+        ls = *dest;
+    }
+
+    xstream_copyin(ls, src->p, length);
+
+    /* in last packet, chan_flags & 0x02 will be true */
+    if (chan_flags & 0x02)
+    {
+        /* rewind stream */
+        ls->p = ls->data;
+        return 1;
+    }
+
+    return 0;
+}
+

sesman/chansrv/chansrv_common.h

@@ -0,0 +1,27 @@
+/**
+ * xrdp: A Remote Desktop Protocol server.
+ *
+ * Copyright (C) Laxmikant Rashinkar 2009-2014
+ *
+ * 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 _CHANSRV_COMMON_H
+#define _CHANSRV_COMMON_H
+
+#include "parse.h"
+
+int read_entire_packet(struct stream *src, struct stream **dest, int chan_flags, int length, int total_length);
+
+#endif
+

sesman/chansrv/sound.c

@@ -46,6 +46,7 @@ static int    g_bytes_in_stream = 0;
 static FIFO   in_fifo;
 
 static struct stream *g_stream_inp = NULL;
+static struct stream *g_stream_incoming_packet = NULL;
 
 #define BBUF_SIZE (1024 * 8)
 char g_buffer[BBUF_SIZE];
@@ -686,6 +687,7 @@ sound_init(void)
     LOG(0, ("sound_init:"));
 
     g_memset(g_sent_flag, 0, sizeof(g_sent_flag));
+    g_stream_incoming_packet = NULL;
 
     /* init sound output */
     sound_send_server_output_formats();
@@ -759,31 +761,39 @@ sound_data_in(struct stream *s, int chan_id, int chan_flags, int length,
 {
     int code;
     int size;
+    int ok_to_free = 1;
 
-    in_uint8(s, code);
-    in_uint8s(s, 1);
-    in_uint16_le(s, size);
+    if (!read_entire_packet(s, &g_stream_incoming_packet, chan_flags, 
+                            length, total_length))
+    {
+        return 0;
+    }
+
+    in_uint8(g_stream_incoming_packet, code);
+    in_uint8s(g_stream_incoming_packet, 1);
+    in_uint16_le(g_stream_incoming_packet, size);
 
     switch (code)
     {
         case SNDC_WAVECONFIRM:
-            sound_process_wave_confirm(s, size);
+            sound_process_wave_confirm(g_stream_incoming_packet, size);
             break;
 
         case SNDC_TRAINING:
-            sound_process_training(s, size);
+            sound_process_training(g_stream_incoming_packet, size);
             break;
 
         case SNDC_FORMATS:
-            sound_process_output_formats(s, size);
+            sound_process_output_formats(g_stream_incoming_packet, size);
             break;
 
         case SNDC_REC_NEGOTIATE:
-            sound_process_input_formats(s, size);
+            sound_process_input_formats(g_stream_incoming_packet, size);
             break;
 
         case SNDC_REC_DATA:
-            sound_process_input_data(s, size);
+            sound_process_input_data(g_stream_incoming_packet, size);
+            ok_to_free = 0;
             break;
 
         default:
@@ -791,6 +801,12 @@ sound_data_in(struct stream *s, int chan_id, int chan_flags, int length,
             break;
     }
 
+    if (ok_to_free && g_stream_incoming_packet)
+    {
+        xstream_free(g_stream_incoming_packet);
+        g_stream_incoming_packet = NULL;
+    }
+
     return 0;
 }