| """An object-oriented interface to .netrc files.""" |
| |
| # Module and documentation by Eric S. Raymond, 21 Dec 1998 |
| |
| import os, shlex, stat |
| |
| __all__ = ["netrc", "NetrcParseError"] |
| |
| |
| class NetrcParseError(Exception): |
| """Exception raised on syntax errors in the .netrc file.""" |
| def __init__(self, msg, filename=None, lineno=None): |
| self.filename = filename |
| self.lineno = lineno |
| self.msg = msg |
| Exception.__init__(self, msg) |
| |
| def __str__(self): |
| return "%s (%s, line %s)" % (self.msg, self.filename, self.lineno) |
| |
| |
| class _netrclex: |
| def __init__(self, fp): |
| self.lineno = 1 |
| self.instream = fp |
| self.whitespace = "\n\t\r " |
| self.pushback = [] |
| |
| def _read_char(self): |
| ch = self.instream.read(1) |
| if ch == "\n": |
| self.lineno += 1 |
| return ch |
| |
| def get_token(self): |
| if self.pushback: |
| return self.pushback.pop(0) |
| token = "" |
| fiter = iter(self._read_char, "") |
| for ch in fiter: |
| if ch in self.whitespace: |
| continue |
| if ch == '"': |
| for ch in fiter: |
| if ch == '"': |
| return token |
| elif ch == "\\": |
| ch = self._read_char() |
| token += ch |
| else: |
| if ch == "\\": |
| ch = self._read_char() |
| token += ch |
| for ch in fiter: |
| if ch in self.whitespace: |
| return token |
| elif ch == "\\": |
| ch = self._read_char() |
| token += ch |
| return token |
| |
| def push_token(self, token): |
| self.pushback.append(token) |
| |
| |
| class netrc: |
| def __init__(self, file=None): |
| default_netrc = file is None |
| if file is None: |
| file = os.path.join(os.path.expanduser("~"), ".netrc") |
| self.hosts = {} |
| self.macros = {} |
| try: |
| with open(file, encoding="utf-8") as fp: |
| self._parse(file, fp, default_netrc) |
| except UnicodeDecodeError: |
| with open(file, encoding="locale") as fp: |
| self._parse(file, fp, default_netrc) |
| |
| def _parse(self, file, fp, default_netrc): |
| lexer = _netrclex(fp) |
| while 1: |
| # Look for a machine, default, or macdef top-level keyword |
| saved_lineno = lexer.lineno |
| toplevel = tt = lexer.get_token() |
| if not tt: |
| break |
| elif tt[0] == '#': |
| if lexer.lineno == saved_lineno and len(tt) == 1: |
| lexer.instream.readline() |
| continue |
| elif tt == 'machine': |
| entryname = lexer.get_token() |
| elif tt == 'default': |
| entryname = 'default' |
| elif tt == 'macdef': |
| entryname = lexer.get_token() |
| self.macros[entryname] = [] |
| while 1: |
| line = lexer.instream.readline() |
| if not line: |
| raise NetrcParseError( |
| "Macro definition missing null line terminator.", |
| file, lexer.lineno) |
| if line == '\n': |
| # a macro definition finished with consecutive new-line |
| # characters. The first \n is encountered by the |
| # readline() method and this is the second \n. |
| break |
| self.macros[entryname].append(line) |
| continue |
| else: |
| raise NetrcParseError( |
| "bad toplevel token %r" % tt, file, lexer.lineno) |
| |
| if not entryname: |
| raise NetrcParseError("missing %r name" % tt, file, lexer.lineno) |
| |
| # We're looking at start of an entry for a named machine or default. |
| login = account = password = '' |
| self.hosts[entryname] = {} |
| while 1: |
| prev_lineno = lexer.lineno |
| tt = lexer.get_token() |
| if tt.startswith('#'): |
| if lexer.lineno == prev_lineno: |
| lexer.instream.readline() |
| continue |
| if tt in {'', 'machine', 'default', 'macdef'}: |
| self.hosts[entryname] = (login, account, password) |
| lexer.push_token(tt) |
| break |
| elif tt == 'login' or tt == 'user': |
| login = lexer.get_token() |
| elif tt == 'account': |
| account = lexer.get_token() |
| elif tt == 'password': |
| password = lexer.get_token() |
| else: |
| raise NetrcParseError("bad follower token %r" % tt, |
| file, lexer.lineno) |
| self._security_check(fp, default_netrc, self.hosts[entryname][0]) |
| |
| def _security_check(self, fp, default_netrc, login): |
| if os.name == 'posix' and default_netrc and login != "anonymous": |
| prop = os.fstat(fp.fileno()) |
| if prop.st_uid != os.getuid(): |
| import pwd |
| try: |
| fowner = pwd.getpwuid(prop.st_uid)[0] |
| except KeyError: |
| fowner = 'uid %s' % prop.st_uid |
| try: |
| user = pwd.getpwuid(os.getuid())[0] |
| except KeyError: |
| user = 'uid %s' % os.getuid() |
| raise NetrcParseError( |
| (f"~/.netrc file owner ({fowner}, {user}) does not match" |
| " current user")) |
| if (prop.st_mode & (stat.S_IRWXG | stat.S_IRWXO)): |
| raise NetrcParseError( |
| "~/.netrc access too permissive: access" |
| " permissions must restrict access to only" |
| " the owner") |
| |
| def authenticators(self, host): |
| """Return a (user, account, password) tuple for given host.""" |
| if host in self.hosts: |
| return self.hosts[host] |
| elif 'default' in self.hosts: |
| return self.hosts['default'] |
| else: |
| return None |
| |
| def __repr__(self): |
| """Dump the class data in the format of a .netrc file.""" |
| rep = "" |
| for host in self.hosts.keys(): |
| attrs = self.hosts[host] |
| rep += f"machine {host}\n\tlogin {attrs[0]}\n" |
| if attrs[1]: |
| rep += f"\taccount {attrs[1]}\n" |
| rep += f"\tpassword {attrs[2]}\n" |
| for macro in self.macros.keys(): |
| rep += f"macdef {macro}\n" |
| for line in self.macros[macro]: |
| rep += line |
| rep += "\n" |
| return rep |
| |
| if __name__ == '__main__': |
| print(netrc()) |
