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

[Pavel Raiskup]

Hi Ian,

On Sunday 29 of May 2016 16:20:00 Ian McLeod wrote:
> * 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.

Good catch, exclude/include is ignored during archive creation.

Could you please post smaller patch just having the important part:

+                  if (!xattrs_masked_out(attr, true /* archiving */))
+                    xheader_xattr_add (st, attr, val, aret);

(+ one prototype above).  And could you please add one new testcase for
--xattrs-{exclude,include}?

Thanks!
Pavel


> ---
>  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)
>