[PATCH v2 5/9] Add make_test_acl() helper to nfs4acl modules

[Chuck Lever <cel@kernel.org>]

From: Chuck Lever <chuck.lever@oracle.com>

I'm about to add several new tests that set a test ACL. This is
common code for all these tests, so introduce a utility function
to construct this ACL for each test.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
 nfs4.0/nfs4acl.py | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/nfs4.0/nfs4acl.py b/nfs4.0/nfs4acl.py
index 0fabd0860cff..e1dfcf0ae371 100644
--- a/nfs4.0/nfs4acl.py
+++ b/nfs4.0/nfs4acl.py
@@ -78,6 +78,28 @@ def mode2acl(mode, dir=False):
              nfsace4(DENIED, 0, negate(other), "EVERYONE@")
              ]
 
+def make_test_acl():
+    """Create a test ACL that maps cleanly to POSIX ACLs
+
+    Uses OWNER@, GROUP@, and EVERYONE@ to match POSIX user/group/other
+    structure, which helps servers that map NFSv4 ACLs to POSIX ACLs.
+
+    Includes both WRITE_DATA and APPEND_DATA for write permission, since
+    Linux NFS server's conservative NFSv4-to-POSIX mapping requires both
+    to grant POSIX write permission.
+    """
+    return [
+        nfsace4(ACE4_ACCESS_ALLOWED_ACE_TYPE, 0,
+                ACE4_READ_DATA | ACE4_WRITE_DATA | ACE4_APPEND_DATA | ACE4_READ_ACL,
+                "OWNER@"),
+        nfsace4(ACE4_ACCESS_ALLOWED_ACE_TYPE, 0,
+                ACE4_READ_DATA,
+                "GROUP@"),
+        nfsace4(ACE4_ACCESS_ALLOWED_ACE_TYPE, 0,
+                ACE4_READ_DATA,
+                "EVERYONE@")
+    ]
+
 def acl2mode(acl):
     """Translate an acl into a 3-digit octal mode"""
     names = ["OWNER@", "GROUP@", "EVERYONE@"]
-- 
2.51.1