[lnst] NetTestCommand: add method check_res_data

[Jiří Pírko]

commit 4af0c307668e2e150a5af3232c4338210e553a89
Author: Ondrej Lichtner <olichtne(a)redhat.com&gt;
Date:   Wed Sep 4 13:36:08 2013 +0200

    NetTestCommand: add method check_res_data
    
    This method checks validity of result data that will eventually be
    serialized into an xml. We have agreed that we will only accept result
    data in form of nested dictionaries, lists and stringable objects.
    
    The function checks the structure of the data and uses regexes to check
    if valid element names and character data can be created.
    
    Signed-off-by: Ondrej Lichtner <olichtne(a)redhat.com&gt;
    Signed-off-by: Jiri Pirko <jiri(a)resnulli.us&gt;

 lnst/Common/NetTestCommand.py |   31 +++++++++++++++++++++++++++++++
 1 files changed, 31 insertions(+), 0 deletions(-)
---
diff --git a/lnst/Common/NetTestCommand.py b/lnst/Common/NetTestCommand.py
index 9131597..d6f6f0f 100644
--- a/lnst/Common/NetTestCommand.py
+++ b/lnst/Common/NetTestCommand.py
@@ -17,6 +17,7 @@ import signal
 import imp
 import pickle, traceback
 import multiprocessing
+import re
 from lnst.Common.ExecCmd import exec_cmd, ExecCmdFail
 from lnst.Common.ConnectionHandler import recv_data, send_data
 
@@ -297,6 +298,7 @@ class NetTestCommandGeneric:
         return result
 
     def format_res_data(self, res_data, level=0):
+        self._check_res_data(res_data)
         formatted_data = ""
         if res_data:
             max_key_len = 0
@@ -314,6 +316,35 @@ class NetTestCommandGeneric:
 
         return formatted_data
 
+    def _check_res_data(self, res_data):
+        name_start_char = u":A-Z_a-z\xC0-\xD6\xD8-\xF6\xF8-\u02FF"\
+                          u"\u0370-\u037D\u037F-\u1FFF\u200C-\u200D"\
+                          u"\u2070-\u218F\u2C00-\u2FEF\u3001-\uD7FF"\
+                          u"\uF900-\uFDCF\uFDF0-\uFFFD\U00010000-\U000EFFFF"
+        name_char = name_start_char + u"\-\.0-9\xB7\u0300-\u036F\u203F-\u2040"
+        name = u"[%s]([%s])*$" % (name_start_char, name_char)
+        char_data = u"[^<&]*"
+        if isinstance(res_data, dict):
+            for key in res_data:
+                if not re.match(name, key, re.UNICODE):
+                    msg = "'%s' can't be used as an xml element
name!" % key
+                    raise CommandException(msg)
+                else:
+                    self._check_res_data(res_data[key])
+        elif isinstance(res_data, list):
+            for i in res_data:
+                self._check_res_data(i)
+        else:
+            try:
+                string = str(res_data)
+            except:
+                msg = "res_data can only contain dictionaries, lists or "\
+                      "stringable objects!"
+                raise CommandException(msg)
+            if not re.match(char_data, string, re.UNICODE):
+                msg = "'%s' can't be used as character data in
xml!" % string
+                raise CommandException(msg)
+
     def _format_cmd_res_header(self):
         return "%-14s" % self._command["type"]