security: shellwords escape attachment file names to prevent remote c…

…ode injection

Merge peristent temp files and fix quotation of shellwords escaped string

s|returnded|returned|

Conflicts:
	doc/Hooks.txt
	lib/sup/message_chunks.rb

doc/Hooks.txt

@@ -50,10 +50,11 @@ before-poll:
 mime-decode:
   ## turn text/html attachments into plain text, unless they are part
   ## of a multipart/alternative pair
+  require 'shellwords'
   unless sibling_types.member? "text/plain"
     case content_type
     when "text/html"
-      `/usr/bin/w3m -dump -T #{content_type} '#{filename}'`
+      `/usr/bin/w3m -dump -T #{content_type} #{Shellwords.escape filename}`
     end
   end
 

lib/sup/message_chunks.rb

@@ -60,6 +60,8 @@ def make_tmpname(prefix_suffix, n)
 module Redwood
 module Chunk
   class Attachment
+    ## please see note in write_to_disk on important usage
+    ## of quotes to avoid remote command injection.
     HookManager.register "mime-decode", <<EOS
 Decodes a MIME attachment into text form. The text will be displayed
 directly in Sup. For attachments that you wish to use a separate program
@@ -76,6 +78,9 @@ class Attachment
   The decoded text of the attachment, or nil if not decoded.
 EOS
 
+
+    ## please see note in write_to_disk on important usage
+    ## of quotes to avoid remote command injection.
     HookManager.register "mime-view", <<EOS
 Views a non-text MIME attachment. This hook allows you to run
 third-party programs for attachments that require such a thing (e.g.
@@ -122,6 +127,8 @@ def initialize content_type, filename, encoded_content, sibling_types
       when /^text\/plain\b/
         @raw_content
       else
+        ## please see note in write_to_disk on important usage
+        ## of quotes to avoid remote command injection.
         HookManager.run "mime-decode", :content_type => content_type,
                         :filename => lambda { write_to_disk },
                         :charset => encoded_content.charset,
@@ -153,18 +160,22 @@ def expandable?; !viewable? end
     def initial_state; :open end
     def viewable?; @lines.nil? end
     def view_default! path
+      ## please see note in write_to_disk on important usage
+      ## of quotes to avoid remote command injection.
       case RbConfig::CONFIG['arch']
         when /darwin/
-          cmd = "open '#{path}'"
+          cmd = "open #{path}"
         else
-          cmd = "/usr/bin/run-mailcap --action=view '#{@content_type}:#{path}'"
+          cmd = "/usr/bin/run-mailcap --action=view #{@content_type}:#{path}"
       end
       debug "running: #{cmd.inspect}"
       BufferManager.shell_out(cmd)
       $? == 0
     end
 
     def view!
+      ## please see note in write_to_disk on important usage
+      ## of quotes to avoid remote command injection.
       write_to_disk do |file|
 
         @@view_tempfiles.push file # make sure the tempfile is not garbage collected before sup stops
@@ -175,6 +186,10 @@ def view!
       end
     end
 
+    ## note that the path returned from write_to_disk is
+    ## Shellwords.escaped and is intended to be used without single
+    ## or double quotes. the use of either opens sup up for remote
+    ## code injection in the file name.
     def write_to_disk
       begin
         file = Tempfile.new(["sup", Shellwords.escape(@filename.gsub("/", "_")) || "sup-attachment"])
@@ -243,7 +258,7 @@ def color; :sig_color end
   class EnclosedMessage
     attr_reader :lines
     def initialize from, to, cc, date, subj
-      @from = from ? "unknown sender" : from.full_adress
+      @from = from ? "unknown sender" : from.full_address
       @to = to ? "" : to.map { |p| p.full_address }.join(", ")
       @cc = cc ? "" : cc.map { |p| p.full_address }.join(", ")
       if date