ssh kitten: Allow using absolute paths for the location of transferred data

Fixes #5607

docs/changelog.rst

@@ -38,6 +38,8 @@ Detailed list of changes
 0.26.5 [future]
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
+- ssh kitten: Allow using absolute paths for the location of transferred data (:iss:`5607`)
+
 - Fix a regression in the previous release that caused a :opt:`resize_draw_strategy` of ``static`` to not work (:iss:`5601`)
 
 - Wayland KDE: Fix abort when pasting into Firefox (:iss:`5603`)

kittens/ssh/options/definition.py

@@ -40,10 +40,9 @@ shell or a :program:`python` executable. If the default :program:`sh` is not
 available or broken, using an alternate interpreter can be useful.
 ''')
 
-opt('remote_dir', '.local/share/kitty-ssh-kitten', option_type='relative_dir', long_text='''
+opt('remote_dir', '.local/share/kitty-ssh-kitten', long_text='''
 The location on the remote host where the files needed for this kitten are
-installed. The location is relative to the HOME directory. Absolute paths or
-paths that resolve to a location outside the HOME are not allowed.
+installed. Relative paths are resolved with respect to :code:`$HOME`.
 ''')
 
 opt('+copy', '', option_type='copy', add_to_default=False, long_text=f'''

kittens/ssh/options/utils.py

@@ -1,7 +1,6 @@
 #!/usr/bin/env python
 # License: GPLv3 Copyright: 2022, Kovid Goyal <kovid at kovidgoyal.net>
 
-import posixpath
 from typing import Any, Dict, Iterable, Optional, Tuple
 
 from ..copy import CopyInstruction, parse_copy_instructions
@@ -9,16 +8,6 @@ from ..copy import CopyInstruction, parse_copy_instructions
 DELETE_ENV_VAR = '_delete_this_env_var_'
 
 
-def relative_dir(val: str) -> str:
-    if posixpath.isabs(val):
-        raise ValueError(f'Absolute paths not allowed. {val} is invalid.')
-    base = '/ffjdg'
-    q = posixpath.normpath(posixpath.join(base, val))
-    if q == base or not q.startswith(base):
-        raise ValueError(f'Paths that escape their parent dir are not allowed. {val} is not valid')
-    return posixpath.normpath(val)
-
-
 def env(val: str, current_val: Dict[str, str]) -> Iterable[Tuple[str, str]]:
     val = val.strip()
     if val:

shell-integration/ssh/bootstrap.py

@@ -205,7 +205,10 @@ def get_data():
         with open(tdir + '/data.sh') as f:
             env_vars = f.read()
             apply_env_vars(env_vars)
-            data_dir = os.path.join(HOME, os.environ.pop('KITTY_SSH_KITTEN_DATA_DIR'))
+            data_dir = os.environ.pop('KITTY_SSH_KITTEN_DATA_DIR')
+            if not os.path.isabs(data_dir):
+                data_dir = os.path.join(HOME, data_dir)
+            data_dir = os.path.abspath(data_dir)
             shell_integration_dir = os.path.join(data_dir, 'shell-integration')
             compile_terminfo(tdir + '/home')
             move(tdir + '/home', HOME)

shell-integration/ssh/bootstrap.sh

@@ -103,7 +103,10 @@ untar_and_read_env() {
     . "$tdir/bootstrap-utils.sh"
     . "$tdir/data.sh"
     [ -z "$KITTY_SSH_KITTEN_DATA_DIR" ] && die "Failed to read SSH data from tty"
-    data_dir="$HOME/$KITTY_SSH_KITTEN_DATA_DIR"
+    case "$KITTY_SSH_KITTEN_DATA_DIR" in
+        /*) data_dir="$KITTY_SSH_KITTEN_DATA_DIR" ;;
+        *) data_dir="$HOME/$KITTY_SSH_KITTEN_DATA_DIR"
+    esac
     shell_integration_dir="$data_dir/shell-integration"
     unset KITTY_SSH_KITTEN_DATA_DIR
     login_shell="$KITTY_LOGIN_SHELL"