[PATCH v2 3/3] sepolgen-ifgen: refactor default policy path retrieval

[Christian Göttsche <cgzones@xxxxxxxxxxxxxx>]

On a SELinux disabled system `selinux.security_policyvers()` will fail;
do not bailout but use a fallback policy version to check if a binary
policy file with that extension exists.

Signed-off-by: Christian Göttsche <cgzones@xxxxxxxxxxxxxx>
---
 python/audit2allow/sepolgen-ifgen | 22 ++++++++++++----------
 1 file changed, 12 insertions(+), 10 deletions(-)

diff --git a/python/audit2allow/sepolgen-ifgen b/python/audit2allow/sepolgen-ifgen
index 4a71cda4..48e60f1d 100644
--- a/python/audit2allow/sepolgen-ifgen
+++ b/python/audit2allow/sepolgen-ifgen
@@ -69,7 +69,11 @@ def get_policy():
     p = selinux.selinux_current_policy_path()
     if p and os.path.exists(p):
         return p
-    i = selinux.security_policyvers()
+    try:
+        i = selinux.security_policyvers()
+    except OSError:
+        # SELinux Disabled Machine
+        i = 50 # some high enough default value
     p = selinux.selinux_binary_policy_path() + "." + str(i)
     while i > 0 and not os.path.exists(p):
         i = i - 1
@@ -80,18 +84,16 @@ def get_policy():
 
 
 def get_attrs(policy_path, attr_helper):
+    if not policy_path:
+        policy_path = get_policy()
+    if not policy_path:
+        sys.stderr.write("No installed policy to check\n")
+        return None
+
     try:
-        if not policy_path:
-            policy_path = get_policy()
-        if not policy_path:
-            sys.stderr.write("No installed policy to check\n")
-            return None
         outfile = tempfile.NamedTemporaryFile()
     except IOError as e:
-        sys.stderr.write("could not open attribute output file\n")
-        return None
-    except OSError:
-        # SELinux Disabled Machine
+        sys.stderr.write("could not open attribute output file: %s\n" % e)
         return None
 
     fd = open("/dev/null", "w")
-- 
2.27.0.rc2