prevent templating of passwords from prompt (#59246) (#59553)

* prevent templating of passwords from prompt (#59246)

* prevent templating of passwords from prompt

  fixes CVE-2019-10206

(cherry picked from commit e9a37f8)

* Improve performane of UnsafeProxy __new__

This adds an early return to the __new__ method of the UnsafeProxy object
which avoids creating the unsafe object if the incoming object is already
unsafe.

(cherry picked from commit c1e23c2)
(cherry picked from commit 490f17c)

changelogs/fragments/dont_template_passwords_from_prompt.yml

@@ -0,0 +1,2 @@
+bugfixes:
+    - resolves CVE-2019-10206, by avoiding templating passwords from prompt as it is probable they have special characters.

lib/ansible/cli/__init__.py

@@ -42,6 +42,7 @@
 from ansible.release import __version__
 from ansible.utils.path import unfrackpath
 from ansible.utils.vars import load_extra_vars, load_options_vars
+from ansible.utils.unsafe_proxy import AnsibleUnsafeBytes
 from ansible.vars.manager import VariableManager
 from ansible.parsing.vault import PromptVaultSecret, get_file_vault_secret
 
@@ -336,6 +337,13 @@ def ask_passwords(self):
         except EOFError:
             pass
 
+        # we 'wrap' the passwords to prevent templating as
+        # they can contain special chars and trigger it incorrectly
+        if sshpass:
+            sshpass = AnsibleUnsafeBytes(sshpass)
+        if becomepass:
+            becomepass = AnsibleUnsafeBytes(becomepass)
+
         return (sshpass, becomepass)
 
     def normalize_become_options(self):

lib/ansible/utils/unsafe_proxy.py

@@ -55,7 +55,7 @@
 
 from collections import Mapping, MutableSequence, Set
 
-from ansible.module_utils.six import string_types, text_type
+from ansible.module_utils.six import string_types, text_type, binary_type
 from ansible.module_utils._text import to_text
 
 
@@ -70,15 +70,24 @@ class AnsibleUnsafeText(text_type, AnsibleUnsafe):
     pass
 
 
+class AnsibleUnsafeBytes(binary_type, AnsibleUnsafe):
+    pass
+
+
 class UnsafeProxy(object):
     def __new__(cls, obj, *args, **kwargs):
+        if isinstance(obj, AnsibleUnsafe):
+            # Already marked unsafe
+            return obj
+
         # In our usage we should only receive unicode strings.
         # This conditional and conversion exists to sanity check the values
         # we're given but we may want to take it out for testing and sanitize
         # our input instead.
+        # Note that this does the wrong thing if we're *intentionall* passing a byte string to this
+        # function.
         if isinstance(obj, string_types):
-            obj = to_text(obj, errors='surrogate_or_strict')
-            return AnsibleUnsafeText(obj)
+            obj = AnsibleUnsafeText(to_text(obj, errors='surrogate_or_strict'))
         return obj