Implement O_WRONLY option for open file

Allows files to be overwritten on Linux without EIO
Logging improved on failed write

sesman/chansrv/chansrv_fuse.c

@@ -72,7 +72,7 @@ int xfuse_file_contents_size(int stream_id, int file_size)                   { r
 int xfuse_add_clip_dir_item(const char *filename, int flags, int size, int lindex) { return 0; }
 int xfuse_create_share(tui32 device_id, const char *dirname)                       { return 0; }
 void xfuse_devredir_cb_open_file(void *vp, tui32 IoStatus, tui32 DeviceId, tui32 FileId)     {}
-void xfuse_devredir_cb_write_file(void *vp, const char *buf, size_t length)        {}
+void xfuse_devredir_cb_write_file(void *vp, tui32 IoStatus, const char *buf, size_t length)        {}
 void xfuse_devredir_cb_read_file(void *vp, const char *buf, size_t length)         {}
 int  xfuse_devredir_cb_enum_dir(void *vp, struct xrdp_inode *xinode)         { return 0; }
 void xfuse_devredir_cb_enum_dir_done(void *vp, tui32 IoStatus)               {}
@@ -1639,12 +1639,12 @@ void xfuse_devredir_cb_open_file(void *vp, tui32 IoStatus, tui32 DeviceId,
     {
         switch (IoStatus)
         {
-        case 0xC0000022:
+        case NT_STATUS_ACCESS_DENIED:
             fuse_reply_err(fip->req, EACCES);
             break;
 
-        case 0xC0000033:
+        case NT_STATUS_OBJECT_NAME_INVALID:
-        case 0xC0000034:
+        case NT_STATUS_OBJECT_NAME_NOT_FOUND:
             fuse_reply_err(fip->req, ENOENT);
             break;
 
@@ -1762,7 +1762,10 @@ void xfuse_devredir_cb_read_file(void *vp, const char *buf, size_t length)
     free(fip);
 }
 
-void xfuse_devredir_cb_write_file(void *vp, const char *buf, size_t length)
+void xfuse_devredir_cb_write_file(void *vp,
+                                  tui32 IoStatus,
+                                  const char *buf,
+                                  size_t length)
 {
     XRDP_INODE   *xinode;
     XFUSE_INFO   *fip;
@@ -1771,20 +1774,34 @@ void xfuse_devredir_cb_write_file(void *vp, const char *buf, size_t length)
     if ((fip == NULL) || (fip->req == NULL) || (fip->fi == NULL))
     {
         log_error("fip, fip->req or fip->fi is NULL");
-        return;
     }
-
-    log_debug("+++ XFUSE_INFO=%p, XFUSE_INFO->fi=%p XFUSE_INFO->fi->fh=0x%llx",
-              fip, fip->fi, (long long) fip->fi->fh);
-
-    fuse_reply_write(fip->req, length);
-
-    /* update file size */
-    if ((xinode = g_xrdp_fs.inode_table[fip->inode]) != NULL)
-        xinode->size += length;
     else
-        log_error("inode at inode_table[%ld] is NULL", fip->inode);
+    {
+        log_debug(
+            "+++ XFUSE_INFO=%p, XFUSE_INFO->fi=%p XFUSE_INFO->fi->fh=0x%llx",
+            fip, fip->fi, (long long) fip->fi->fh);
 
+        if (IoStatus != NT_STATUS_SUCCESS)
+        {
+            log_error("Write NTSTATUS is %d", (int) IoStatus);
+            fuse_reply_err(fip->req, EIO);
+        }
+        else
+        {
+            fuse_reply_write(fip->req, length);
+
+            /* update file size */
+            if ((xinode = g_xrdp_fs.inode_table[fip->inode]) != NULL)
+            {
+                xinode->size += length;
+            }
+            else
+            {
+                log_error("inode at inode_table[%ld] is NULL", fip->inode);
+            }
+
+        }
+    }
     free(fip);
 }
 
@@ -2551,11 +2568,24 @@ static void xfuse_cb_open(fuse_req_t req, fuse_ino_t ino,
     }
     if (xinode->mode & S_IFDIR)
     {
-        log_debug("reading a dir not allowed!");
+        log_debug("reading/writing a dir not allowed!");
         fuse_reply_err(req, EISDIR);
         return;
     }
 
+    switch (fi->flags & O_ACCMODE)
+    {
+        case O_RDONLY:
+        case O_WRONLY:
+        case O_RDWR:
+            break;
+
+        default:
+            log_debug("Invalid access mode specified");
+            fuse_reply_err(req, EINVAL);
+            return;
+     }
+
     device_id = xfuse_get_device_id_for_inode(ino, full_path);
 
     if (xinode->is_loc_resource)
@@ -2594,7 +2624,12 @@ static void xfuse_cb_open(fuse_req_t req, fuse_ino_t ino,
     {
         cptr = "\\";
     }
-    /* get dev_redir to open the remote file */
+    /* get dev_redir to open the remote file
+     *
+     * For a successful call, if the caller has set O_TRUNC when writing
+     * the file, fuse should call us back via fuse_cb_setattr() to set
+     * the size to zero - we don't need to do this ourselves.
+     */
     if (dev_redir_file_open((void *) fip, device_id, cptr,
                             fi->flags, S_IFREG, NULL))
     {

sesman/chansrv/chansrv_fuse.h

@@ -58,7 +58,11 @@ int xfuse_add_clip_dir_item(const char *filename, int flags, int size, int linde
 int xfuse_devredir_cb_enum_dir(void *vp, struct xrdp_inode *xinode);
 void xfuse_devredir_cb_enum_dir_done(void *vp, tui32 IoStatus);
 void xfuse_devredir_cb_open_file(void *vp, tui32 IoStatus, tui32 DeviceId, tui32 FileId);
-void xfuse_devredir_cb_write_file(void *vp, const char *buf, size_t length);
+void xfuse_devredir_cb_write_file(
+                                 void *vp,
+                                 tui32 IoStatus,
+                                 const char *buf,
+                                 size_t length);
 void xfuse_devredir_cb_read_file(void *vp, const char *buf, size_t length);
 void xfuse_devredir_cb_rmdir_or_file(void *vp, tui32 IoStatus);
 void xfuse_devredir_cb_rename_file(void *vp, tui32 IoStatus);

sesman/chansrv/devredir.c

@@ -822,7 +822,8 @@ dev_redir_proc_device_iocompletion(struct stream *s)
         }
         else
         {
-            xfuse_devredir_cb_write_file(fuse_data->data_ptr, s->p, Length);
+            xfuse_devredir_cb_write_file(fuse_data->data_ptr, IoStatus,
+                                         s->p, Length);
             devredir_irp_delete(irp);
         }
         break;
@@ -1107,14 +1108,30 @@ dev_redir_file_open(void *fusep, tui32 device_id, const char *path,
     }
     else
     {
-        log_debug("open file in O_RDWR");
 #if 1
-        /* without the 0x00000010 rdesktop opens files in */
+        switch(mode & O_ACCMODE)
-        /* O_RDONLY instead of O_RDWR mode                */
+        {
-        if (mode & O_RDWR)
+            case O_RDONLY:
-            DesiredAccess = DA_FILE_READ_DATA | DA_FILE_WRITE_DATA | DA_SYNCHRONIZE | 0x00000010;
+                log_debug("open file in O_RDONLY");
-        else
+                DesiredAccess = DA_FILE_READ_DATA | DA_SYNCHRONIZE;
-            DesiredAccess = DA_FILE_READ_DATA | DA_SYNCHRONIZE;
+                break;
+
+            case O_WRONLY:
+                log_debug("open file in O_WRONLY");
+                DesiredAccess = DA_FILE_WRITE_DATA | DA_SYNCHRONIZE;
+                break;
+
+            default:
+                /*
+                 * The access mode could conceivably be invalid here,
+                 * but we assume this has been checked by the caller
+                 */
+                log_debug("open file in O_RDWR");
+                /* without the 0x00000010 rdesktop opens files in */
+                /* O_RDONLY instead of O_RDWR mode                */
+                DesiredAccess = DA_FILE_READ_DATA | DA_FILE_WRITE_DATA | 
+                                DA_SYNCHRONIZE | 0x00000010;
+        }
 
         CreateOptions = CO_FILE_SYNCHRONOUS_IO_NONALERT;
         CreateDisposition = CD_FILE_OPEN; // WAS 1
@@ -1283,7 +1300,7 @@ dev_redir_file_write(void *fusep, tui32 DeviceId, tui32 FileId,
     if ((irp = devredir_irp_find_by_fileid(FileId)) == NULL)
     {
         log_error("no IRP found with FileId = %d", FileId);
-        xfuse_devredir_cb_write_file(fusep, NULL, 0);
+        xfuse_devredir_cb_write_file(fusep, NT_STATUS_UNSUCCESSFUL, NULL, 0);
         xstream_free(s);
         return -1;
     }
@@ -1292,7 +1309,7 @@ dev_redir_file_write(void *fusep, tui32 DeviceId, tui32 FileId,
     if ((new_irp = devredir_irp_clone(irp)) == NULL)
     {
         /* system out of memory */
-        xfuse_devredir_cb_write_file(fusep, NULL, 0);
+        xfuse_devredir_cb_write_file(fusep, NT_STATUS_UNSUCCESSFUL, NULL, 0);
         xstream_free(s);
         return -1;
     }

sesman/chansrv/devredir.h

@@ -260,6 +260,9 @@ enum CREATE_OPTIONS
 
 #define NT_STATUS_SUCCESS               0x00000000
 #define NT_STATUS_UNSUCCESSFUL          0xC0000001
+#define NT_STATUS_ACCESS_DENIED         0xC0000022
+#define NT_STATUS_OBJECT_NAME_INVALID   0xC0000033
+#define NT_STATUS_OBJECT_NAME_NOT_FOUND 0xC0000034
 
 /*
  * File system ioctl codes