# safetk.tcl -- # # Support procs to use Tk in safe interpreters. # # Copyright (c) 1997 Sun Microsystems, Inc. # # See the file "license.terms" for information on usage and redistribution # of this file, and for a DISCLAIMER OF ALL WARRANTIES. # see safetk.n for documentation # # # Note: It is now ok to let untrusted code being executed # between the creation of the interp and the actual loading # of Tk in that interp because the C side Tk_Init will # now look up the parent interp and ask its safe::TkInit # for the actual parameters to use for it's initialization (if allowed), # not relying on the child state. # # We use opt (optional arguments parsing) package require opt 0.4.1; namespace eval ::safe { # counter for safe toplevels variable tkSafeId 0 } # # tkInterpInit : prepare the child interpreter for tk loading # most of the real job is done by loadTk # returns the child name (tkInterpInit does) # proc ::safe::tkInterpInit {child argv} { global env tk_library # We have to make sure that the tk_library variable is normalized. set tk_library [file normalize $tk_library] # Clear Tk's access for that interp (path). allowTk $child $argv # Ensure tk_library and subdirs (eg, ttk) are on the access path ::interp eval $child [list set tk_library [::safe::interpAddToAccessPath $child $tk_library]] foreach subdir [::safe::AddSubDirs [list $tk_library]] { ::safe::interpAddToAccessPath $child $subdir } return $child } # tkInterpLoadTk: # Do additional configuration as needed (calling tkInterpInit) # and actually load Tk into the child. # # Either contained in the specified windowId (-use) or # creating a decorated toplevel for it. # empty definition for auto_mkIndex proc ::safe::loadTk {} {} ::tcl::OptProc ::safe::loadTk { {child -interp "name of the child interpreter"} {-use -windowId {} "window Id to use (new toplevel otherwise)"} {-display -displayName {} "display name to use (current one otherwise)"} } { set displayGiven [::tcl::OptProcArgGiven "-display"] if {!$displayGiven} { # Try to get the current display from "." # (which might not exist if the parent is tk-less) if {[catch {set display [winfo screen .]}]} { if {[info exists ::env(DISPLAY)]} { set display $::env(DISPLAY) } else { Log $child "no winfo screen . nor env(DISPLAY)" WARNING set display ":0.0" } } } # Get state for access to the cleanupHook. namespace upvar ::safe S$child state if {![::tcl::OptProcArgGiven "-use"]} { # create a decorated toplevel lassign [tkTopLevel $child $display] w use # set our delete hook (child arg is added by interpDelete) # to clean up both window related code and tkInit(child) set state(cleanupHook) [list tkDelete {} $w] } else { # set our delete hook (child arg is added by interpDelete) # to clean up tkInit(child) set state(cleanupHook) [list disallowTk] # Let's be nice and also accept tk window names instead of ids if {[string match ".*" $use]} { set windowName $use set use [winfo id $windowName] set nDisplay [winfo screen $windowName] } else { # Check for a better -display value # (works only for multi screens on single host, but not # cross hosts, for that a tk window name would be better # but embeding is also usefull for non tk names) if {![catch {winfo pathname $use} name]} { set nDisplay [winfo screen $name] } else { # Can't have a better one set nDisplay $display } } if {$nDisplay ne $display} { if {$displayGiven} { return -code error -errorcode {TK DISPLAY SAFE} \ "conflicting -display $display and -use $use -> $nDisplay" } else { set display $nDisplay } } } # Prepares the child for tk with those parameters tkInterpInit $child [list "-use" $use "-display" $display] load {} Tk $child return $child } proc ::safe::TkInit {interpPath} { variable tkInit if {[info exists tkInit($interpPath)]} { set value $tkInit($interpPath) Log $interpPath "TkInit called, returning \"$value\"" NOTICE return $value } else { Log $interpPath "TkInit called for interp with clearance:\ preventing Tk init" ERROR return -code error -errorcode {TK SAFE PERMISSION} "not allowed" } } # safe::allowTk -- # # Set tkInit(interpPath) to allow Tk to be initialized in # safe::TkInit. # # Arguments: # interpPath child interpreter handle # argv arguments passed to safe::TkInterpInit # # Results: # none. proc ::safe::allowTk {interpPath argv} { variable tkInit set tkInit($interpPath) $argv return } # safe::disallowTk -- # # Unset tkInit(interpPath) to disallow Tk from getting initialized # in safe::TkInit. # # Arguments: # interpPath child interpreter handle # # Results: # none. proc ::safe::disallowTk {interpPath} { variable tkInit # This can already be deleted by the DeleteHook of the interp if {[info exists tkInit($interpPath)]} { unset tkInit($interpPath) } return } # safe::tkDelete -- # # Clean up the window associated with the interp being deleted. # # Arguments: # interpPath child interpreter handle # # Results: # none. proc ::safe::tkDelete {W window child} { # we are going to be called for each widget... skip untill it's # top level Log $child "Called tkDelete $W $window" NOTICE if {[::interp exists $child]} { if {[catch {::safe::interpDelete $child} msg]} { Log $child "Deletion error : $msg" } } if {[winfo exists $window]} { Log $child "Destroy toplevel $window" NOTICE destroy $window } # clean up tkInit(child) disallowTk $child return } proc ::safe::tkTopLevel {child display} { variable tkSafeId incr tkSafeId set w ".safe$tkSafeId" if {[catch {toplevel $w -screen $display -class SafeTk} msg]} { return -code error -errorcode {TK TOPLEVEL SAFE} \ "Unable to create toplevel for \"$child\" ($msg)" } Log $child "New toplevel $w" NOTICE set msg "Untrusted Tcl applet ($child)" wm title $w $msg # Control frame (we must create a style for it) ttk::style layout TWarningFrame {WarningFrame.border -sticky nswe} ttk::style configure TWarningFrame -background red set wc $w.fc ttk::frame $wc -relief ridge -borderwidth 4 -style TWarningFrame # We will destroy the interp when the window is destroyed bindtags $wc [concat Safe$wc [bindtags $wc]] bind Safe$wc [list ::safe::tkDelete %W $w $child] ttk::label $wc.l -text $msg -anchor w # We want the button to be the last visible item # (so be packed first) and at the right and not resizing horizontally # frame the button so it does not expand horizontally # but still have the default background instead of red one from the parent ttk::frame $wc.fb -borderwidth 0 ttk::button $wc.fb.b -text "Delete" \ -command [list ::safe::tkDelete $w $w $child] pack $wc.fb.b -side right -fill both pack $wc.fb -side right -fill both -expand 1 pack $wc.l -side left -fill both -expand 1 -ipady 2 pack $wc -side bottom -fill x # Container frame frame $w.c -container 1 pack $w.c -fill both -expand 1 # return both the toplevel window name and the id to use for embedding list $w [winfo id $w.c] }