shell bypass 403
import os
import re
import glob
from . import repository
import tuned.logs
import tuned.consts as consts
from tuned.utils.commands import commands
log = tuned.logs.get()
cmd = commands()
class Functions():
"""
Built-in functions
"""
def __init__(self):
self._repository = repository.Repository()
self._parse_init()
def _parse_init(self, s = ""):
self._cnt = 0
self._str = s
self._len = len(s)
self._stack = []
self._esc = False
def _curr_char(self):
return self._str[self._cnt] if self._cnt < self._len else ""
def _curr_substr(self, _len):
return self._str[self._cnt:self._cnt + _len]
def _push_pos(self, esc):
self._stack.append((esc, self._cnt))
def _sub(self, a, b, s):
self._str = self._str[:a] + s + self._str[b + 1:]
self._len = len(self._str)
self._cnt += len(s) - (b - a + 1)
if self._cnt < 0:
self._cnt = 0
def _process_func(self, _from):
sl = re.split(r'(?<!\\):', self._str[_from:self._cnt])
if sl[0] != "${f":
return
sl = [str(v).replace("\:", ":") for v in sl]
if not re.match(r'\w+$', sl[1]):
log.error("invalid function name '%s'" % sl[1])
return
try:
f = self._repository.load_func(sl[1])
except ImportError:
log.error("function '%s' not implemented" % sl[1])
return
s = f.execute(sl[2:])
if s is None:
return
self._sub(_from, self._cnt, s)
def _process(self, s):
self._parse_init(s)
while self._cnt < self._len:
if self._curr_char() == "}":
try:
si = self._stack.pop()
except IndexError:
log.error("invalid variable syntax, non pair '}' in: '%s'" % s)
return self._str
# if not escaped
if not si[0]:
self._process_func(si[1])
elif self._curr_substr(2) == "${":
self._push_pos(self._esc)
if self._curr_char() == "\\":
self._esc = True
else:
self._esc = False
self._cnt += 1
if len(self._stack):
log.error("invalid varialbe syntax, non pair '{' in: '%s'" % s)
return self._str
def expand(self, s):
if s is None or s == "":
return s
# expand functions and convert all \${f:*} to ${f:*} (unescape)
return re.sub(r'\\(\${f:.*})', r'\1', self._process(s))