Create openscap formula

This formula allows to install openscap schemas and utils.
Also, here is a simple oscap execution module.

Change-Id: Ib113f9a739deafbc4cf85c97b071636d0161cb54
Closes-PROD: https://mirantis.jira.com/browse/PROD-20392
diff --git a/_modules/oscap/__init__.py b/_modules/oscap/__init__.py
new file mode 100644
index 0000000..88cdcba
--- /dev/null
+++ b/_modules/oscap/__init__.py
@@ -0,0 +1,106 @@
+from __future__ import absolute_import
+from oscap.commands import xccdf, oval
+import logging
+import os
+import salt.utils
+import shutil
+import stat
+
+_OSCAP_XCCDF_EXIT_CODES_MAP = {
+    0: True,  # all rules pass
+    1: False,  # there is an error during evaluation
+    2: True  # there is at least one rule with either fail or unknown result
+}
+
+DIR_MODE = '0750'
+
+log = logging.getLogger(__name__)
+
+def __virtual__():
+    if not salt.utils.which('oscap'):
+        return (False, 'oscap is required.')
+    return 'oscap'
+
+def eval(evaltype,
+         benchmark,
+         profile='default',
+         xccdf_version='1.2',
+         tailoring_id=None,
+         fetch_from_master=False,
+         benchmark_url=None,
+         benchmark_basepath='output',
+         saltenv='base',
+         results_dir=None):
+    '''
+    `oscap eval` wrapper
+    :param  evaltype:           what to evaluate, can be `xccdf` or `oval`
+    :param  profile:            xccdf profile (default 'default')
+    :param  xccdf_version       xccdf benchmark version (default 1.2)
+    :param  tailoring_id        id of your tailoring data (default None)
+    :param  fetch_from_master:  fetch oscap input data from the master (default False)
+    :param  benchmark_basepath: basepath where the benchmark will be searched (default 'output')
+    :param  saltenv:            saltenv, used for cached files (default 'base')
+    :param  results_dir:        directory for storing results (default {{__opts__[cachedir]}}/files/openscap/latest)
+
+    :return:                    success,returncode,results_dir, optionally stderr
+
+    Usage example:
+
+        salt MINION oscap.eval xccdf /tmp/myxccdf.xml tailoring_id=myenv_oscap_variables profile='anssi_nt28_high'
+    '''
+    success = False
+    stderr = None
+    returncode = None
+    pillar_data = None
+
+    latest_dir = os.path.join(__opts__['cachedir'], 'files', 'openscap', 'latest')
+    results_dir = os.path.normpath(results_dir) if results_dir else latest_dir
+
+    benchmark_url = benchmark_url if benchmark_url else \
+                        'salt://{}/{}'.format(benchmark_basepath,
+                                              os.path.dirname(benchmark))
+
+    if fetch_from_master:
+        _ret_ = __salt__['cp.cache_dir'](benchmark_url)
+        benchmark = benchmark[1:] if os.path.isabs(benchmark) else benchmark
+        benchmark = os.path.join(__opts__['cachedir'], 'files',
+                                 saltenv, benchmark_basepath, benchmark)
+
+    if evaltype == 'xccdf':
+        if tailoring_id:
+            pillar_data = __salt__['pillar.get']('openscap:tailoring:{}'\
+                                                 .format(tailoring_id))
+        (stdout, stderr, rc, temp_dir) = xccdf(benchmark,
+                                              profile=profile,
+                                              pillar_data=pillar_data,
+                                              tailoring_id=tailoring_id,
+                                              xccdf_version=xccdf_version)
+
+        success = _OSCAP_XCCDF_EXIT_CODES_MAP[rc]
+    elif evaltype == 'oval':
+        (stdout, stderr, rc, temp_dir) = oval(benchmark)
+        success = not rc
+    else:
+        raise RuntimeError('Unsupported oscap command "{}"'.format(evaltype))
+
+    ret = {
+        'success': success,
+        'returncode': rc,
+        'results_dir': results_dir
+        }
+
+    if success:
+        mode = int(str(stat.S_IMODE(int(DIR_MODE))), 8)
+        base_dir = os.path.dirname(results_dir)
+        if os.path.isdir(results_dir):
+            shutil.rmtree(results_dir)
+        if not os.path.isdir(base_dir):
+            os.makedirs(base_dir)
+            os.chmod(base_dir, mode)
+        os.rename(temp_dir, latest_dir)
+        os.chmod(latest_dir, mode)
+
+    if stderr:
+        ret['stderr'] = stderr
+
+    return ret