Allow running remote rsync as sudo

man/simple_backup.1

@@ -91,11 +91,11 @@ Don't use systemd journal for logging
 By default, the following rsync options are used:
 .RS
 .PP
-\-a \-r \-c \-v \-h \-H \-X
+    \-a \-r \-v \-h \-s \-H \-X
 .PP
 Using \-\-rsync\-options it is possible to manually select which options to use. Supported values are the following:
 .PP
-\-a, \-l, \-p, \-t, \-g, \-o, \-c, \-h, \-D, \-H, \-X
+    \-a, \-l, \-p, \-t, \-g, \-o, \-c, \-h, \-D, \-H, \-X, \-s
 .PP
 Options \-r and \-v are used in any case. Not that options must be specified without dash (\-), for example:
 .PP
@@ -103,7 +103,16 @@ Options \-r and \-v are used in any case. Not that options must be specified wit
     simple_backup \-\-rsync\-options a l p
 .EE
 .TP
-Check rsync(1) for details about the options.
+Check
+.B rsync (1)
+for details about the options.
+.RE
+.TP
+.B \-\-remote\-sudo
+Run rsync on the remote server with sudo. For this to work the user used to login to the server obviously need to be allowed to use sudo. In addition, the user need to be able to run rsync with sudo without a password. To do this, /etc/sudoers on the server need to be edited adding a line like this one:
+.RS
+.PP
+    <username> ALL=NOPASSWD:<path/to/rsync>
 .RE
 .SH CONFIGURATION
 An example configuration file is provided at \(aq/usr/share/doc/simple_backup/simple_backup.conf\(aq.

simple_backup/simple_backup.conf

@@ -18,3 +18,4 @@ keep=-1
 # host=
 # username=
 # ssh_keyfile=
+# remote_sudo=

simple_backup/simple_backup.py

@@ -137,7 +137,7 @@ class Backup:
     """
 
     def __init__(self, inputs, output, exclude, keep, options, host=None,
-                 username=None, ssh_keyfile=None, remove_before=False):
+                 username=None, ssh_keyfile=None, remote_sudo=False, remove_before=False):
         self.inputs = inputs
         self.output = output
         self.exclude = exclude
@@ -146,6 +146,7 @@ class Backup:
         self.host = host
         self.username = username
         self.ssh_keyfile = ssh_keyfile
+        self.remote_sudo = remote_sudo
         self._remove_before = remove_before
         self._last_backup = ''
         self._server = ''
@@ -470,6 +471,9 @@ class Backup:
         else:
             rsync = f'{rsync} -e \'ssh -o StrictHostKeyChecking=no\''
 
+        if self._remote and self.remote_sudo:
+            rsync = f'{rsync} --rsync-path="sudo rsync"'
+
         args = shlex.split(rsync)
 
         with Popen(args, stdin=PIPE, stdout=PIPE, stderr=STDOUT, shell=False) as p:
@@ -562,8 +566,9 @@ def _parse_arguments():
                         help='Remove old backups before executing the backup, instead of after')
     parser.add_argument('--no-syslog', action='store_true', help='Disable systemd journal logging')
     parser.add_argument('--rsync-options', nargs='+',
-                        choices=['a', 'l', 'p', 't', 'g', 'o', 'c', 'h', 'D', 'H', 'X'],
+                        choices=['a', 'l', 'p', 't', 'g', 'o', 'c', 'h', 's', 'D', 'H', 'X'],
                         help='Specify options for rsync')
+    parser.add_argument('--remote-sudo', action='store_true', help='Run rsync on remote server with sudo if allowed')
 
     args = parser.parse_args()
 
@@ -591,7 +596,7 @@ def _read_config(config_file):
     if not os.path.isfile(config_file):
         logger.warning('Config file %s does not exist', config_file)
 
-        return None, None, None, None, None, None, None
+        return None, None, None, None, None, None, None, None
 
     config = configparser.ConfigParser()
     config.read(config_file)
@@ -610,9 +615,17 @@ def _read_config(config_file):
     inputs = list(set(inputs))
     output = config.get(section, 'backup_dir')
     output = os.path.expanduser(output.replace('~', f'~{user}'))
-    exclude = config.get(section, 'exclude')
-    exclude = exclude.split(',')
-    keep = config.getint(section, 'keep')
+
+    try:
+        exclude = config.get(section, 'exclude')
+        exclude = exclude.split(',')
+    except configparser.NoOptionError:
+        exclude = []
+
+    try:
+        keep = config.getint(section, 'keep')
+    except configparser.NoOptionError:
+        keep = -1
 
     try:
         host = config.get('server', 'host')
@@ -626,7 +639,12 @@ def _read_config(config_file):
     except (configparser.NoSectionError, configparser.NoOptionError):
         ssh_keyfile = None
 
-    return inputs, output, exclude, keep, host, username, ssh_keyfile
+    try:
+        remote_sudo = config.getboolean('server', 'remote_sudo')
+    except (configparser.NoSectionError, configparser.NoOptionError):
+        remote_sudo = False
+
+    return inputs, output, exclude, keep, host, username, ssh_keyfile, remote_sudo
 
 
 def _notify(text):
@@ -659,7 +677,7 @@ def simple_backup():
             pass
 
     try:
-        inputs, output, exclude, keep, host, username, ssh_keyfile = _read_config(args.config)
+        inputs, output, exclude, keep, host, username, ssh_keyfile, remote_sudo = _read_config(args.config)
     except (configparser.NoSectionError, configparser.NoOptionError):
         logger.critical('Bad configuration file')
         sys.exit(1)
@@ -699,10 +717,13 @@ def simple_backup():
     if args.compress:
         rsync_options.append('-z')
 
+    if args.remote_sudo is not None:
+        remote_sudo = args.remote_sudo
+
     rsync_options = ' '.join(rsync_options)
 
     backup = Backup(inputs, output, exclude, keep, rsync_options, host, username,
-                    ssh_keyfile, remove_before=args.remove_before_backup)
+                    ssh_keyfile, remote_sudo, remove_before=args.remove_before_backup)
 
     return_code = backup.check_params()