Cyptography pr 20566 rebase (#25560)

Make pyca/cryptography the preferred backend for cryptographic needs (mainly vault) falling back to pycrypto

pyca/cryptography is already implicitly a dependency in many cases
through paramiko (2.0+) as well as the new openssl_publickey module,
which requires pyOpenSSL 16.0+. Additionally, pyca/cryptography is
an optional dep for better performance with vault already.

This commit leverages cryptography's padding, constant time comparisons,
and CBC/CTR modes to reduce the amount of code ansible needs to
maintain.

* Handle wrong password given for VaultAES format

* Do not display deprecation warning for cryptography on python-2.6

* Namespace all of the pycrypto imports and always import them

  Makes unittests better and the code less likely to get stupid mistakes
  (like using HMAC from cryptogrpahy when the one from pycrypto is needed)

* Add back in atfork since we need pycrypto to reinitialize its RNG just in case we're being used with old paramiko

* contrib/inventory/gce: Remove spurious require on pycrypto

(cherry picked from commit 9e16b9db275263b3ea8d1b124966fdebfc9ab271)

* Add cryptography to ec2_win_password module requirements
  * Fix python3 bug which would pass text strings to a function which
    requires byte strings.

* Attempt to add pycrypto version to setup deps

* Change hacking README for dual pycrypto/cryptography

* update dependencies for various CI scripts

* additional CI dockerfile/script updates

* add paramiko to the windows and sanity requirement set

  This is needed because ansible lists it as a requirement. Previously
  the missing dep wasn't enforced, but cryptography imports pkg_resources
  so you can't ignore a requirement any more

* Add integration test cases for old vault and for wrong passwords

* helper script for manual testing of pycrypto/cryptography

* Skip the pycrypto tests so that users without it installed can still run the unittests

* Run unittests for vault with both cryptography and pycrypto backend

test/runner/requirements/constraints.txt

@@ -3,3 +3,4 @@ pywinrm >= 0.2.1 # 0.1.1 required, but 0.2.1 provides better performance
 pylint >= 1.5.3, < 1.7.0 # 1.4.1 adds JSON output, but 1.5.3 fixes bugs related to JSON output
 sphinx < 1.6 ; python_version < '2.7' # sphinx 1.6 and later require python 2.7 or later
 isort < 4.2.8 # 4.2.8 changes import sort order requirements which breaks previously passing pylint tests
+pycrypto >= 2.6 # Need features found in 2.6 and greater

test/runner/requirements/integration.txt

@@ -1,3 +1,4 @@
+cryptography
 jinja2
 jmespath
 junit-xml

test/runner/requirements/network-integration.txt

@@ -1,5 +1,5 @@
+cryptography
 jinja2
 junit-xml
 paramiko
-pycrypto
 pyyaml

test/runner/requirements/sanity.txt

@@ -1,6 +1,8 @@
+cryptography
 jinja2
 mock
 pep8
+paramiko
 pylint
 pytest
 rstcheck

test/runner/requirements/units.txt

@@ -1,11 +1,12 @@
 boto
 boto3
 placebo
+cryptography
+pycrypto
 jinja2
 mock
 nose
 passlib
-pycrypto
 pytest
 pytest-mock
 pytest-xdist

test/runner/requirements/windows-integration.txt

@@ -1,4 +1,6 @@
+cryptography
 jinja2
 junit-xml
+paramiko
 pywinrm
 pyyaml