CopyToDomZero changed

Initial version

CopyToDomZero.md

@@ -4,4 +4,19 @@ title: CopyToDomZero
 permalink: /wiki/CopyToDomZero/
 ---
 
-TODO
+Copying files to between VMs and Dom0
+-------------------------------------
+
+First, there should normally be few reasons for the user to want to copy files from VMs to Dom0, as Dom0 only acts as a "thin trusted terminal", and no user applications run there. However, one exception to this is if we want to copy a desktop wallpaper, that we normally have in one of the AppVMs (e.g. in the 'personal' AppVM where we got it from our camera, or downloaded from the Internet). While it's a well justified reason, one should remember, however, that copying untrusted files to Dom0 might be a fatal security problem. Imagine what would happen if the wallpaper (e.g. a JPEG file) was somehow malformed and was in fact attempting to exploit a hypothetical JPEG parser bug in Dom0 code (e.g. in the Dom0's Xorg/KDE component that parses the wallpaper and displays it).
+
+For this reason we intentionally do not provide a convenient tool for copying files between VMs and Dom0 (while we provide a tool for copying files between VMs). However, if you're determined to copy some files to Dom0 anyway, you can use the following method (run this command from Dom0's console):
+
+``` {.wiki}
+qvm-run --pass-io <src_domain> 'cat /path/to/file_in_src_domain' > /path/to/file_name_in_dom0
+```
+
+BTW, you can use the same method to copy files from Dom0 to VMs, e.g. logs (although in Qubes 1.0 this won't be needed, as we will provide a convenient one-click solution for copying logs to Qubes global clipboard):
+
+``` {.wiki}
+cat /path/to/file_in_dom0 | qvm-run --pass-io <dst_domain> 'cat > /path/to/file_name_in_appvm'
+```