[Bug-tar] [PATCH] Bugfix - fix xattr exclude/include for archive create

[Ian McLeod]

* src/xattrs.c (xattrs_xattrs_get): apply exclude/include mask when
  fetching extended attributes

This makes archive create behavior consistent with the documentation.
Without this change xattr include/exclude options are accepted when
creating an archive but are silently ignored.
---
 src/xattrs.c | 103 ++++++++++++++++++++++++++++++-----------------------------
 1 file changed, 53 insertions(+), 50 deletions(-)

diff --git a/src/xattrs.c b/src/xattrs.c
index 8e56168..a272af7 100644
--- a/src/xattrs.c
+++ b/src/xattrs.c
@@ -434,8 +434,55 @@ xattrs_clear_setup (void)
   clear_mask_map (&xattrs_setup.excl);
 }
 
-/* get all xattrs from file given by FILE_NAME or FD (when non-zero).  This
-   includes all the user.*, security.*, system.*, etc. available domains */
+static bool
+xattrs_matches_mask (const char *kw, struct xattrs_mask_map *mm)
+{
+  int i;
+
+  if (!mm->size)
+    return false;
+
+  for (i = 0; i < mm->used; i++)
+    if (fnmatch (mm->masks[i], kw, 0) == 0)
+      return true;
+
+  return false;
+}
+
+#define USER_DOT_PFX "user."
+
+static bool
+xattrs_kw_included (const char *kw, bool archiving)
+{
+  if (xattrs_setup.incl.size)
+    return xattrs_matches_mask (kw, &xattrs_setup.incl);
+  else if (archiving)
+    return true;
+  else
+    return strncmp (kw, USER_DOT_PFX, sizeof (USER_DOT_PFX) - 1) == 0;
+}
+
+static bool
+xattrs_kw_excluded (const char *kw, bool archiving)
+{
+  return xattrs_setup.excl.size ?
+    xattrs_matches_mask (kw, &xattrs_setup.excl) : false;
+}
+
+/* Check whether the xattr with keyword KW should be discarded from list of
+   attributes that are going to be archived/excluded (set ARCHIVING=true for
+   archiving, false for excluding) */
+static bool
+xattrs_masked_out (const char *kw, bool archiving)
+{
+  return xattrs_kw_included (kw, archiving) ?
+    xattrs_kw_excluded (kw, archiving) : true;
+}
+
+/* get xattrs from file given by FILE_NAME or FD (when non-zero)
+   xattrs are checked against the user supplied include/exclude mask
+   if no mask is given this includes all the user.*, security.*, system.*,
+   etc. available domains */
 void
 xattrs_xattrs_get (int parentfd, char const *file_name,
                    struct tar_stat_info *st, int fd)
@@ -480,8 +527,6 @@ xattrs_xattrs_get (int parentfd, char const *file_name,
               size_t len = strlen (attr);
               ssize_t aret = 0;
 
-              /* Archive all xattrs during creation, decide at extraction time
-               * which ones are of interest/use for the target filesystem. */
               while (((fd == 0)
                       ? ((aret = lgetxattrat (parentfd, file_name, attr,
                                               val, asz)) == -1)
@@ -492,7 +537,10 @@ xattrs_xattrs_get (int parentfd, char const *file_name,
                 }
 
               if (aret != -1)
-                xheader_xattr_add (st, attr, val, aret);
+                {
+                  if (!xattrs_masked_out(attr, true))
+                    xheader_xattr_add (st, attr, val, aret);
+                }
               else if (errno != ENOATTR)
                 call_arg_warn ((fd == 0) ? "lgetxattrat"
                                : "fgetxattr", file_name);
@@ -595,51 +643,6 @@ xattrs_selinux_set (struct tar_stat_info const *st,
     }
 }
 
-static bool
-xattrs_matches_mask (const char *kw, struct xattrs_mask_map *mm)
-{
-  int i;
-
-  if (!mm->size)
-    return false;
-
-  for (i = 0; i < mm->used; i++)
-    if (fnmatch (mm->masks[i], kw, 0) == 0)
-      return true;
-
-  return false;
-}
-
-#define USER_DOT_PFX "user."
-
-static bool
-xattrs_kw_included (const char *kw, bool archiving)
-{
-  if (xattrs_setup.incl.size)
-    return xattrs_matches_mask (kw, &xattrs_setup.incl);
-  else if (archiving)
-    return true;
-  else
-    return strncmp (kw, USER_DOT_PFX, sizeof (USER_DOT_PFX) - 1) == 0;
-}
-
-static bool
-xattrs_kw_excluded (const char *kw, bool archiving)
-{
-  return xattrs_setup.excl.size ?
-    xattrs_matches_mask (kw, &xattrs_setup.excl) : false;
-}
-
-/* Check whether the xattr with keyword KW should be discarded from list of
-   attributes that are going to be archived/excluded (set ARCHIVING=true for
-   archiving, false for excluding) */
-static bool
-xattrs_masked_out (const char *kw, bool archiving)
-{
-  return xattrs_kw_included (kw, archiving) ?
-    xattrs_kw_excluded (kw, archiving) : true;
-}
-
 void
 xattrs_xattrs_set (struct tar_stat_info const *st,
                    char const *file_name, char typeflag, int later_run)
-- 
2.5.5