[rdiff-backup-users] hasfullperms(), isgroup() and funny indexes

[Ryan Castle]

Hi,

This is probably only relevant to Ben and other's who've read some of the code.

We're trying to get the web interface to restores of old versions of directories, however we don't want the webserver to run as anything privileged and we don't want to expose the backup repositories to anything but the webserver. At the moment the webserver is added to the "rbackup" group which is the primary group of all the rdiff-backup. Restoring files seems to work fine, but when we attempt to restore a directory rdiff-backup thinks the webserver isn't a member of the directories' group, and fails when it tries to chmod() the files to 770. I've added a function issecondarygroup() to the rpath class. It currently uses the 'id' program to get all the process' group ids. Total hack, but I couldn't find any python docs that told me do it nicely. Then I 'or'ed that onto the isgroup() return statement. Do you think this is likely to cause problems?

def issecondarygroup(self):
        gids = os.popen('id -G').read().strip().split(' ')
        for gid in gids:
            if self.data['gid'] == int(gid): return 1
        return 0

This seems to have worked. However, I get an assert failure in __call__() now. I'm not entirely sure what it does. It seems to be checking if the first element of the index array is higher than the first value of old_index. Not sure why it does that. When I comment it out, it runs OK, but I've probably broken something else. Can you explain what that assert is trying to do?

def __call__(self, rp):
        """Given rpath, change permissions up and including rp"""
        index, old_index = rp.index, self.current_index
        self.current_index = index
        if not index or index == old_index: return
        assert index > old_index, (index, old_index)
        self.restore_old(rp, index)
        self.add_new(rp, old_index, index)

Thanks,
Ryan


Stack trace of assertion error

  File "/usr/bin/rdiff-backup", line 23, in ?
    rdiff_backup.Main.Main(sys.argv[1:])
  File "/usr/lib/python2.3/site-packages/rdiff_backup/Main.py", line 247, in Main
    take_action(rps)
  File "/usr/lib/python2.3/site-packages/rdiff_backup/Main.py", line 219, in take_action
    elif action == "restore": Restore(*rps)
  File "/usr/lib/python2.3/site-packages/rdiff_backup/Main.py", line 452, in Restore
    inc_rpath, dest_rp, time)
  File "/usr/lib/python2.3/site-packages/rdiff_backup/restore.py", line 50, in Restore
    TargetS.patch(target, diff_iter)
  File "/usr/lib/python2.3/site-packages/rdiff_backup/restore.py", line 280, in patch
    for diff in rorpiter.FillInIter(diff_iter, target):
  File "/usr/lib/python2.3/site-packages/rdiff_backup/rorpiter.py", line 181, in FillInIter
    for rp in rpiter:
  File "/usr/lib/python2.3/site-packages/rdiff_backup/restore.py", line 244, in get_diffs_from_collated
    diff = cls.get_diff(mir_rorp, target_rorp)
  File "/usr/lib/python2.3/site-packages/rdiff_backup/restore.py", line 257, in get_diff
    mir_rorp.setfile(cls.rf_cache.get_fp(expanded_index))
  File "/usr/lib/python2.3/site-packages/rdiff_backup/restore.py", line 336, in get_fp
    rf = self.get_rf(index)
  File "/usr/lib/python2.3/site-packages/rdiff_backup/restore.py", line 330, in get_rf
    if (index[:-1] == rf.index[:-1] or not
  File "/usr/lib/python2.3/site-packages/rdiff_backup/restore.py", line 355, in add_rfs
    if Globals.process_uid != 0: self.perm_changer(temp_rf.mirror_rp)
  File "/usr/lib/python2.3/site-packages/rdiff_backup/restore.py", line 661, in __call__
    assert index > old_index, (index, old_index)
AssertionError: (('etc', '3270'), ('etc', '3270', 'charset', 'thai'))

--
Ryan Castle <address@hidden>
Solutions First