posix: add ACL translation for the GF_POSIX_ACL_*_KEY xattr

Adding support for two virtual extended attributes that are used for
converting a binary POSIX ACL to a POSIX.1e long ACL text format. This
makes it possible to transfer the ACL over the network to a different OS
which can convert the POSIX.1e text format to its native structures.

The following xattrs are sent over RPC in SETXATTR/GETXATTR procedures,
and contain the POSIX.1e long ACL text format:

- glusterfs.posix.acl: maps to ACL_TYPE_ACCESS
- glusterfs.posix.default_acl: maps to ACL_TYPE_DEFAULT

acl_from_text() (from libacl) converts the text format into an acl_t
structure. This structure is then used by acl_set_file() to set the ACL
in the filesystem.

libacl-devel is needed for linking against libacl, so it has been added
to the BuildRequires in the .spec.

NetBSD does not support POSIX ACLs. Trying to get/set POSIX ACLs on a
storage server running NetBSD, an error will be returned with errno set
to ENOTSUP. Faking support, but not enforcing ACLs seems wrong to me.

URL: http://www.gluster.org/community/documentation/index.php/Features/Improved_POSIX_ACLs
BUG: 1185654
Change-Id: Ic5eb73d69190d3492df2f711d0436775eeea7de3
Signed-off-by: Niels de Vos <ndevos@redhat.com>
Reviewed-on: http://review.gluster.org/9627
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: soumya k <skoduri@redhat.com>
Reviewed-by: Raghavendra Bhat <raghavendra@redhat.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/xlators/storage/posix/src/posix.h b/xlators/storage/posix/src/posix.h
index 870315d0ea2..bdb56b1d59d 100644
--- a/xlators/storage/posix/src/posix.h
+++ b/xlators/storage/posix/src/posix.h
@@ -236,4 +236,10 @@ posix_get_ancestry (xlator_t *this, inode_t *leaf_inode,
 void
 posix_gfid_unset (xlator_t *this, dict_t *xdata);
 
+int
+posix_pacl_set (const char *path, const char *key, const char *acl_s);
+
+int
+posix_pacl_get (const char *path, const char *key, char **acl_s);
+
 #endif /* _POSIX_H */